2023 |
Volpi, M; Jouclas, R; Liu, J; Liu, G; Catalano, L; McIntosh, N; Bardini, M; Gatsios, C; Modesti, F; Turetta, N; Beljonne, D; Cornil, J; Kennedy, A R; Koch, N; Erk, P; Samorì, P; Schweicher, G; Geerts, Y H Enantiopure Dinaphtho[2,3-b:2,3-f]thieno[3,2-b]thiophenes: Reaching High Magnetoresistance Effect in OFETs Journal Article In: Adv. Sci., 10 (2301914), 2023. @article{Volpi2023, title = {Enantiopure Dinaphtho[2,3-b:2,3-f]thieno[3,2-b]thiophenes: Reaching High Magnetoresistance Effect in OFETs}, author = {M. Volpi and R. Jouclas and J. Liu and G. Liu and L. Catalano and N. McIntosh and M. Bardini and C. Gatsios and F. Modesti and N. Turetta and D. Beljonne and J. Cornil and A. R. Kennedy and N. Koch and P. Erk and P. Samorì and G. Schweicher and Y. H. Geerts}, editor = {Wiley Online Library}, url = { https://doi.org/10.1002/advs.202301914}, year = {2023}, date = {2023-09-15}, journal = {Adv. Sci.}, volume = {10}, number = {2301914}, abstract = {Chiral molecules are known to behave as spin filters due to the chiral induced spin selectivity (CISS) effect. Chirality can be implemented in molecular semiconductors in order to study the role of the CISS effect in charge transport and to find new materials for spintronic applications. In this study, the design and synthesis of a new class of enantiopure chiral organic semiconductors based on the well-known dinaphtho[2,3-b:2,3-f]thieno[3,2-b]thiophene (DNTT) core functionalized with chiral alkyl side chains is presented. When introduced in an organic field-effect transistor (OFET) with magnetic contacts, the two enantiomers, (R)-DNTT and (S)-DNTT, show an opposite behavior with respect to the relative direction of the magnetization of the contacts, oriented by an external magnetic field. Each enantiomer displays an unexpectedly high magnetoresistance over one preferred orientation of the spin current injected from the magnetic contacts. The result is the first reported OFET in which the current can be switched on and off upon inversion of the direction of the applied external magnetic field. This work contributes to the general understanding of the CISS effect and opens new avenues for the introduction of organic materials in spintronic devices.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Chiral molecules are known to behave as spin filters due to the chiral induced spin selectivity (CISS) effect. Chirality can be implemented in molecular semiconductors in order to study the role of the CISS effect in charge transport and to find new materials for spintronic applications. In this study, the design and synthesis of a new class of enantiopure chiral organic semiconductors based on the well-known dinaphtho[2,3-b:2,3-f]thieno[3,2-b]thiophene (DNTT) core functionalized with chiral alkyl side chains is presented. When introduced in an organic field-effect transistor (OFET) with magnetic contacts, the two enantiomers, (R)-DNTT and (S)-DNTT, show an opposite behavior with respect to the relative direction of the magnetization of the contacts, oriented by an external magnetic field. Each enantiomer displays an unexpectedly high magnetoresistance over one preferred orientation of the spin current injected from the magnetic contacts. The result is the first reported OFET in which the current can be switched on and off upon inversion of the direction of the applied external magnetic field. This work contributes to the general understanding of the CISS effect and opens new avenues for the introduction of organic materials in spintronic devices. |
Vitale, S; Puozzo, H; Saiev, S; Bonnaud, L; Ricciardulli, A G; Ciesielski, A; Beljonne, D; Samorì, P In: Chem. Mater., 35 , pp. 6909–6919, 2023. @article{Vitale2023, title = {Tuning the Piezoresistive Behavior of Graphene-Polybenzoxazine Nanocomposites: Toward High-Performance Materials for Pressure Sensing Applications}, author = {S. Vitale and H. Puozzo and S. Saiev and L. Bonnaud and A. G. Ricciardulli and A. Ciesielski and D. Beljonne and P. Samorì}, editor = {ACS Publcation}, url = {https://doi.org/10.1021/acs.chemmater.3c01191}, year = {2023}, date = {2023-09-12}, journal = {Chem. Mater.}, volume = {35}, pages = { 6909–6919}, abstract = {Flexible piezoresistive pressure sensors are key components in wearable technologies for health monitoring, digital healthcare, human–machine interfaces, and robotics. Among active materials for pressure sensing, graphene-based materials are extremely promising because of their outstanding physical characteristics. Currently, a key challenge in pressure sensing is the sensitivity enhancement through the fine tuning of the active material’s electro-mechanical properties. Here, we describe a novel versatile approach to modulating the sensitivity of graphene-based piezoresistive pressure sensors by combining chemically reduced graphene oxide (rGO) with a thermally responsive material, namely, a novel trifunctional polybenzoxazine thermoset precursor based on tris(3-aminopropyl)amine and phenol reagents (PtPA). The integration of rGO in a polybenzoxazine thermoresist matrix results in an electrically conductive nanocomposite where the thermally triggered resist’s polymerization modulates the active material rigidity and consequently the piezoresistive response to pressure. Pressure sensors comprising the rGO-PtPA blend exhibit sensitivities ranging from 10–2 to 1 kPa–1, which can be modulated by controlling the rGO:PtPA ratio or the curing temperature. Our rGO-PtPA blend represents a proof-of-concept graphene-based nanocomposite with on-demand piezoresistive behavior. Combined with solution processability and a thermal curing process compatible with large-area coatings technologies on flexible supports, this method holds great potential for applications in pressure sensing for health monitoring.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Flexible piezoresistive pressure sensors are key components in wearable technologies for health monitoring, digital healthcare, human–machine interfaces, and robotics. Among active materials for pressure sensing, graphene-based materials are extremely promising because of their outstanding physical characteristics. Currently, a key challenge in pressure sensing is the sensitivity enhancement through the fine tuning of the active material’s electro-mechanical properties. Here, we describe a novel versatile approach to modulating the sensitivity of graphene-based piezoresistive pressure sensors by combining chemically reduced graphene oxide (rGO) with a thermally responsive material, namely, a novel trifunctional polybenzoxazine thermoset precursor based on tris(3-aminopropyl)amine and phenol reagents (PtPA). The integration of rGO in a polybenzoxazine thermoresist matrix results in an electrically conductive nanocomposite where the thermally triggered resist’s polymerization modulates the active material rigidity and consequently the piezoresistive response to pressure. Pressure sensors comprising the rGO-PtPA blend exhibit sensitivities ranging from 10–2 to 1 kPa–1, which can be modulated by controlling the rGO:PtPA ratio or the curing temperature. Our rGO-PtPA blend represents a proof-of-concept graphene-based nanocomposite with on-demand piezoresistive behavior. Combined with solution processability and a thermal curing process compatible with large-area coatings technologies on flexible supports, this method holds great potential for applications in pressure sensing for health monitoring. |
Sens, M; de Oliveira, Furlan R; Berto, M; Palmieri, M; Ruini, E; Livio, P A; Conti, A; Pinti, M; Salvarani, C; Cossarizza, A; Cabot, J M; Ricart, J; Casalini, S; González-García, M B; Fanjul-Bolado, P; Bortolotti, C A; Samorì, P; Biscarini, F Reduced Graphene Oxide Electrolyte-Gated Transistor Immunosensor with Highly Selective Multiparametric Detection of Anti-Drug Antibodies Journal Article In: Adv. Mater., 35 (2211352), 2023. @article{Sens2023, title = {Reduced Graphene Oxide Electrolyte-Gated Transistor Immunosensor with Highly Selective Multiparametric Detection of Anti-Drug Antibodies}, author = {M. Sens and R. Furlan de Oliveira and M. Berto and M. Palmieri and E. Ruini and P. A. Livio and A. Conti and M. Pinti and C. Salvarani and A. Cossarizza and J. M. Cabot and J. Ricart and S. Casalini and M. B. González-García and P. Fanjul-Bolado and C. A. Bortolotti and P. Samorì and F. Biscarini}, editor = {Wiley Online Library}, url = {https://doi.org/10.1002/adma.202211352}, year = {2023}, date = {2023-09-07}, journal = {Adv. Mater.}, volume = {35}, number = {2211352}, abstract = {The advent of immunotherapies with biological drugs has revolutionized the treatment of cancers and auto-immune diseases. However, in some patients, the production of anti-drug antibodies (ADAs) hampers the drug efficacy. The concentration of ADAs is typically in the range of 1–10 pm; hence their immunodetection is challenging. ADAs toward Infliximab (IFX), a drug used to treat rheumatoid arthritis and other auto-immune diseases, are focussed. An ambipolar electrolyte-gated transistor (EGT) immunosensor is reported based on a reduced graphene oxide (rGO) channel and IFX bound to the gate electrode as the specific probe. The rGO-EGTs are easy to fabricate and exhibit low voltage operations (≤ 0.3 V), a robust response within 15 min, and ultra-high sensitivity (10 am limit of detection). A multiparametric analysis of the whole rGO-EGT transfer curves based on the type-I generalized extreme value distribution is proposed. It is demonstrated that it allows to selectively quantify ADAs also in the co-presence of its antagonist tumor necrosis factor alpha (TNF-α), the natural circulating target of IFX.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The advent of immunotherapies with biological drugs has revolutionized the treatment of cancers and auto-immune diseases. However, in some patients, the production of anti-drug antibodies (ADAs) hampers the drug efficacy. The concentration of ADAs is typically in the range of 1–10 pm; hence their immunodetection is challenging. ADAs toward Infliximab (IFX), a drug used to treat rheumatoid arthritis and other auto-immune diseases, are focussed. An ambipolar electrolyte-gated transistor (EGT) immunosensor is reported based on a reduced graphene oxide (rGO) channel and IFX bound to the gate electrode as the specific probe. The rGO-EGTs are easy to fabricate and exhibit low voltage operations (≤ 0.3 V), a robust response within 15 min, and ultra-high sensitivity (10 am limit of detection). A multiparametric analysis of the whole rGO-EGT transfer curves based on the type-I generalized extreme value distribution is proposed. It is demonstrated that it allows to selectively quantify ADAs also in the co-presence of its antagonist tumor necrosis factor alpha (TNF-α), the natural circulating target of IFX. |
Crispi, S; Nocito, G; Nastasi, F; Condorelli, G; Ricciardulli, A G; Samorì, P; Conoci, S; Neri, G Development of a novel C-dots conductometric sensor for NO sensing Journal Article In: Sens. Actuators B Chem., 390 (133957 ), 2023. @article{Crispi2023, title = {Development of a novel C-dots conductometric sensor for NO sensing}, author = {S. Crispi and G. Nocito and F. Nastasi and G. Condorelli and A. G. Ricciardulli and P. Samorì and S. Conoci and G. Neri}, editor = {Science Direct}, url = {https://doi.org/10.1016/j.snb.2023.133957}, year = {2023}, date = {2023-09-01}, journal = {Sens. Actuators B Chem.}, volume = {390}, number = {133957 }, abstract = {Carbon dots (CDs, C-dots) obtained from waste produced during the production of olive oil in Calabria (Italy) have been investigated as a gas sensing material for the sensitive and selective detection of nitric oxide (NO) in air. The obtained CDs were characterized by XPS, FT-IR and ATR-FTIR. CDs were deposited to yield a sensitive layer on a conductometric platform and tested for gas sensing, showing promising characteristics for the selective monitoring of NO in air. The response of CDs composite to NO was 1.5 @ 1250 ppm and the response and recovery times amounted to 90 and 200 s, respectively. The sensing behavior of C-dots prepared using olive waste from a different geographic location (Puglia, Italy) was also reported and compared. It has been found that the sensing behavior of the two different materials based sensors investigated towards nitrogen oxides (NO and NO2) was completely different. On the one hand, the former exhibited selectivity towards NO. On the other, the latter showed prominent selectivity towards NO2. This behavior can be ascribed to the different functional groups exposed on the C-dots surface undergoing non-covalent interactions with a marked specificity of the hydroxyl and ethers moieties for NO and NO2, respectively.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Carbon dots (CDs, C-dots) obtained from waste produced during the production of olive oil in Calabria (Italy) have been investigated as a gas sensing material for the sensitive and selective detection of nitric oxide (NO) in air. The obtained CDs were characterized by XPS, FT-IR and ATR-FTIR. CDs were deposited to yield a sensitive layer on a conductometric platform and tested for gas sensing, showing promising characteristics for the selective monitoring of NO in air. The response of CDs composite to NO was 1.5 @ 1250 ppm and the response and recovery times amounted to 90 and 200 s, respectively. The sensing behavior of C-dots prepared using olive waste from a different geographic location (Puglia, Italy) was also reported and compared. It has been found that the sensing behavior of the two different materials based sensors investigated towards nitrogen oxides (NO and NO2) was completely different. On the one hand, the former exhibited selectivity towards NO. On the other, the latter showed prominent selectivity towards NO2. This behavior can be ascribed to the different functional groups exposed on the C-dots surface undergoing non-covalent interactions with a marked specificity of the hydroxyl and ethers moieties for NO and NO2, respectively. |
Pakulski, D; Gorczyński, A; Brykczyńska, D; Montes-García, V; Czepa, W; Janica, I; Bielejewski, M; Kubicki, M; Patroniak, V; Samorì, P; Ciesielski, A New Anderson-Based Polyoxometalate Covalent Organic Frameworks as Electrodes for Energy Storage Boosted Through Keto-Enol Tautomerization Journal Article In: Angew. Chem. Int. Ed., 62 (e202305239), 2023. @article{Pakulski2023, title = {New Anderson-Based Polyoxometalate Covalent Organic Frameworks as Electrodes for Energy Storage Boosted Through Keto-Enol Tautomerization}, author = {D. Pakulski and A. Gorczyński and D. Brykczyńska and V. Montes-García and W. Czepa and I. Janica and M. Bielejewski and M. Kubicki and V. Patroniak and P. Samorì and A. Ciesielski}, editor = {Wiley Online Library}, url = {https://doi.org/10.1002/anie.202305239}, year = {2023}, date = {2023-08-07}, journal = {Angew. Chem. Int. Ed.}, volume = {62}, number = {e202305239}, abstract = {The unique electrochemical properties of polyoxometalates (POMs) render them ideal components for the fabrication of next-generation high-performance energy storage systems. However, their practical applications have been hindered by their high solubility in common electrolytes. This problem can be overcome by the effective hybridization of POMs with other materials. Here we present the design and synthesis of two novel polyoxometalate-covalent organic frameworks (POCOF) via one-pot solvothermal strategy between an amino-functionalized Anderson-type POM and a trialdehyde-based building unit. We show that structural and functional complexity can be enriched by adding hydroxyl groups in the 2,4,6 position to the benzene-1,3,5-tricarbaldehyde allowing to exploit for the first time in POCOFs the keto-enol tautomerization as additional feature to impart greater chemical stability to the COFs and enhanced properties leading to large specific surface area (347 m2/g) and superior electrochemical performance of the POCOF-1 electrodes, when compared with POCOF-2 electrodes that possess only imine-type linkage and with pristine POM electrodes. Specifically, POCOF-1 electrodes display remarkable specific, areal, and volumetric capacitance (125 F/g, 248 mF/cm2 and 41.9 mF/cm3, respectively) at a current density of 0.5 A/g, a maximum energy density (56.2 Wh/kg), a maximum power density (3.7 kW/kg) and an outstanding cyclability (90 % capacitance retention after 5000 cycles).}, keywords = {}, pubstate = {published}, tppubtype = {article} } The unique electrochemical properties of polyoxometalates (POMs) render them ideal components for the fabrication of next-generation high-performance energy storage systems. However, their practical applications have been hindered by their high solubility in common electrolytes. This problem can be overcome by the effective hybridization of POMs with other materials. Here we present the design and synthesis of two novel polyoxometalate-covalent organic frameworks (POCOF) via one-pot solvothermal strategy between an amino-functionalized Anderson-type POM and a trialdehyde-based building unit. We show that structural and functional complexity can be enriched by adding hydroxyl groups in the 2,4,6 position to the benzene-1,3,5-tricarbaldehyde allowing to exploit for the first time in POCOFs the keto-enol tautomerization as additional feature to impart greater chemical stability to the COFs and enhanced properties leading to large specific surface area (347 m2/g) and superior electrochemical performance of the POCOF-1 electrodes, when compared with POCOF-2 electrodes that possess only imine-type linkage and with pristine POM electrodes. Specifically, POCOF-1 electrodes display remarkable specific, areal, and volumetric capacitance (125 F/g, 248 mF/cm2 and 41.9 mF/cm3, respectively) at a current density of 0.5 A/g, a maximum energy density (56.2 Wh/kg), a maximum power density (3.7 kW/kg) and an outstanding cyclability (90 % capacitance retention after 5000 cycles). |
Xu, N; Shi, L; Pei, X; Zhang, W; Chen, J; Han, Z; Samorì, P; Wang, J; Wang, P; Shi, Y; Li, S Oxidation kinetics and non-Marcusian charge transfer in dimensionally confined semiconductors Journal Article In: Nat. Commun., 14 (4074), 2023. @article{Xu2023, title = {Oxidation kinetics and non-Marcusian charge transfer in dimensionally confined semiconductors}, author = {N. Xu and L. Shi and X. Pei and W. Zhang and J. Chen and Z. Han and P. Samorì and J. Wang and P. Wang and Y. Shi and S. Li}, editor = {Nature communication}, url = {https://doi.org/10.1038/s41467-023-39781-y}, year = {2023}, date = {2023-07-10}, journal = {Nat. Commun.}, volume = {14}, number = {4074}, abstract = {Electrochemical reactions represent essential processes in fundamental chemistry that foster a wide range of applications. Although most electrochemical reactions in bulk substances can be well described by the classical Marcus-Gerischer charge transfer theory, the realistic reaction character and mechanism in dimensionally confined systems remain unknown. Here, we report the multiparametric survey on the kinetics of lateral photooxidation in structurally identical WS2 and MoS2 monolayers, where electrochemical oxidation occurs at the atomically thin monolayer edges. The oxidation rate is correlated quantitatively with various crystallographic and environmental parameters, including the density of reactive sites, humidity, temperature, and illumination fluence. In particular, we observe distinctive reaction barriers of 1.4 and 0.9 eV for the two structurally identical semiconductors and uncover an unusual non-Marcusian charge transfer mechanism in these dimensionally confined monolayers due to the limit in reactant supplies. A scenario of band bending is proposed to explain the discrepancy in reaction barriers. These results add important knowledge into the fundamental electrochemical reaction theory in low-dimensional systems.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Electrochemical reactions represent essential processes in fundamental chemistry that foster a wide range of applications. Although most electrochemical reactions in bulk substances can be well described by the classical Marcus-Gerischer charge transfer theory, the realistic reaction character and mechanism in dimensionally confined systems remain unknown. Here, we report the multiparametric survey on the kinetics of lateral photooxidation in structurally identical WS2 and MoS2 monolayers, where electrochemical oxidation occurs at the atomically thin monolayer edges. The oxidation rate is correlated quantitatively with various crystallographic and environmental parameters, including the density of reactive sites, humidity, temperature, and illumination fluence. In particular, we observe distinctive reaction barriers of 1.4 and 0.9 eV for the two structurally identical semiconductors and uncover an unusual non-Marcusian charge transfer mechanism in these dimensionally confined monolayers due to the limit in reactant supplies. A scenario of band bending is proposed to explain the discrepancy in reaction barriers. These results add important knowledge into the fundamental electrochemical reaction theory in low-dimensional systems. |
Gullace, S; Cusin, L; Richard, F; Israfilov, N; Ciesielski, A; Samorì, P In: Adv. Mater. Interfaces,, 10 (2300124), 2023. @article{Gullace2023, title = {The Role of Superadsorbent Polymers on Covalent Organic Frameworks-Based Solid Electrolytes: Investigation of the Ionic Conductivity and Relaxation}, author = {S. Gullace and L. Cusin and F. Richard and N. Israfilov and A. Ciesielski and P. Samorì}, editor = {Wiley Online Library}, url = {https://doi.org/10.1002/admi.202300124}, year = {2023}, date = {2023-06-06}, journal = {Adv. Mater. Interfaces,}, volume = {10}, number = {2300124}, abstract = {The scarcity of fossil fuels calls for immediate action toward the development of clean and renewable energy resources. In this context, proton exchange membrane fuel cells (PEMFCs) are gaining ever-increasing attention as clean technology. Although covalent organic frameworks (COFs) do not usually exhibit high intrinsic proton conductivity (σ), they have been recently proposed as solid polymer electrolytes in PEMFCs, thanks to their high crystallinity and stability to acids and bases. Here, a simple strategy is presented to improve the performance of poor COF-based proton conductors through addition of sodium polyacrylate (PANa) superadsorbent polymer. Electrochemical impedance spectroscopy investigations after activation at high temperature and relative humidity (RH) provide insights into the role of PANa, whose presence is key to preserve high σ at low RH. The humidity-dependent X-ray diffraction study reveals a strengthening of the stacking interaction along the COF (100) plane direction with increasing humidity, through the formation of H-bonding, thus promoting proton hopping. The study of the dielectric properties as a function of PANa content enables to determine a Debye relaxation regime for the COF/PANa blend with a maximum relaxation frequency of 1513 and 6606 Hz for the pristine COF and the COF/PANa blend, respectively, at their maximum operating temperatures.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The scarcity of fossil fuels calls for immediate action toward the development of clean and renewable energy resources. In this context, proton exchange membrane fuel cells (PEMFCs) are gaining ever-increasing attention as clean technology. Although covalent organic frameworks (COFs) do not usually exhibit high intrinsic proton conductivity (σ), they have been recently proposed as solid polymer electrolytes in PEMFCs, thanks to their high crystallinity and stability to acids and bases. Here, a simple strategy is presented to improve the performance of poor COF-based proton conductors through addition of sodium polyacrylate (PANa) superadsorbent polymer. Electrochemical impedance spectroscopy investigations after activation at high temperature and relative humidity (RH) provide insights into the role of PANa, whose presence is key to preserve high σ at low RH. The humidity-dependent X-ray diffraction study reveals a strengthening of the stacking interaction along the COF (100) plane direction with increasing humidity, through the formation of H-bonding, thus promoting proton hopping. The study of the dielectric properties as a function of PANa content enables to determine a Debye relaxation regime for the COF/PANa blend with a maximum relaxation frequency of 1513 and 6606 Hz for the pristine COF and the COF/PANa blend, respectively, at their maximum operating temperatures. |
Malaki, M; Jiang, X; Wang, H; Podila, R; Zhang, H; Samorì, P; Varma, R S MXenes: from past to future perspectives Journal Article In: Chem. Eng. J., 463 (142351), 2023. @article{Malaki2023, title = {MXenes: from past to future perspectives}, author = {M. Malaki and X. Jiang and H. Wang and R. Podila and H. Zhang and P. Samorì and R. S. Varma}, editor = {Science Direct}, url = {https://doi.org/10.1016/j.cej.2023.142351}, year = {2023}, date = {2023-05-01}, journal = {Chem. Eng. J.}, volume = {463}, number = {142351}, abstract = {MXenes have recently emerged as a revolutionary class of material displaying exceptional tailored-made properties. The onward journey and remarkable rise are establishing MXene-based materials as multifaceted playgrounds for the technology-oriented explorations and are offering a tool-box for the ad hoc tailoring of advanced materials capable to effectively address current and future societal challenges. Unexpected applications have witnessed a tremendous growth owing to the material’s unique chemical and physical properties including, among others, optical, electrical, mechanical and thermal characteristics. Attaining an in-depth and critical understanding on the broadest arsenal of such unique and new properties as well as the synergistic effects of the assorted characteristics will play a pivotal role for new discoveries in both, research and industrial sectors. Herein, the current challenges, bottlenecks, controversies, as well as emerging opportunities are critically discussed by providing, in a single package, comprehensive insight into chemical and physical properties with a particular focus on their disruptive potential for technological applications. The key fundamental properties ranging from electrical, magnetic, thermal, mechanical, tribological to sensing features are elucidated to stimulate emerging opportunities and lucrative potentials with the ultimate goal being the technological exploitation of newfound materials and structures with targeted attributes.}, keywords = {}, pubstate = {published}, tppubtype = {article} } MXenes have recently emerged as a revolutionary class of material displaying exceptional tailored-made properties. The onward journey and remarkable rise are establishing MXene-based materials as multifaceted playgrounds for the technology-oriented explorations and are offering a tool-box for the ad hoc tailoring of advanced materials capable to effectively address current and future societal challenges. Unexpected applications have witnessed a tremendous growth owing to the material’s unique chemical and physical properties including, among others, optical, electrical, mechanical and thermal characteristics. Attaining an in-depth and critical understanding on the broadest arsenal of such unique and new properties as well as the synergistic effects of the assorted characteristics will play a pivotal role for new discoveries in both, research and industrial sectors. Herein, the current challenges, bottlenecks, controversies, as well as emerging opportunities are critically discussed by providing, in a single package, comprehensive insight into chemical and physical properties with a particular focus on their disruptive potential for technological applications. The key fundamental properties ranging from electrical, magnetic, thermal, mechanical, tribological to sensing features are elucidated to stimulate emerging opportunities and lucrative potentials with the ultimate goal being the technological exploitation of newfound materials and structures with targeted attributes. |
Czepa, W; Witomska, S; Samorì, P; Ciesielski, A A Graphene Oxide–Thioamide Polymer Hybrid for High-Performance Supercapacitor Electrodes Journal Article In: Small Sci., 3 (2300013), 2023. @article{Czepa2023, title = {A Graphene Oxide–Thioamide Polymer Hybrid for High-Performance Supercapacitor Electrodes}, author = {W. Czepa and S. Witomska and P. Samorì and A. Ciesielski}, editor = {Wiley Online Library}, url = {https://doi.org/10.1002/smsc.202300013}, year = {2023}, date = {2023-05-01}, journal = {Small Sci.}, volume = {3}, number = {2300013}, abstract = {The controlled chemical functionalization of graphene oxide (GO) represents a powerful strategy to finely tune its physical and chemical properties toward applications in energy storage. Herein, an unprecedented approach for the GO modification with thioamide-based polymers featuring numerous heteroatoms (S,N,O) is reported, which is instrumental for achieving superior electrochemical performance in symmetric supercapacitors. While the electrochemical investigations in aqueous electrolytes reveal specific capacitance of 221 F g−1 at 1 A g−1, the use of organic media allows the specific capacitance to be boosted up to 340 F g−1. Additionally, the increase of operating window yields energy densities as high as 94.4 Wh kg−1, thereby exceeding state-of-the-art performances of GO-based supercapacitors. Furthermore, the symmetric devices exhibit great robustness in both aqueous and organic electrolytes as evidenced by an excellent stability after 5000 working cycles (>98% in H2SO4 and >90% in TEABF4/ACN).}, keywords = {}, pubstate = {published}, tppubtype = {article} } The controlled chemical functionalization of graphene oxide (GO) represents a powerful strategy to finely tune its physical and chemical properties toward applications in energy storage. Herein, an unprecedented approach for the GO modification with thioamide-based polymers featuring numerous heteroatoms (S,N,O) is reported, which is instrumental for achieving superior electrochemical performance in symmetric supercapacitors. While the electrochemical investigations in aqueous electrolytes reveal specific capacitance of 221 F g−1 at 1 A g−1, the use of organic media allows the specific capacitance to be boosted up to 340 F g−1. Additionally, the increase of operating window yields energy densities as high as 94.4 Wh kg−1, thereby exceeding state-of-the-art performances of GO-based supercapacitors. Furthermore, the symmetric devices exhibit great robustness in both aqueous and organic electrolytes as evidenced by an excellent stability after 5000 working cycles (>98% in H2SO4 and >90% in TEABF4/ACN). |
Pandey, P; Fijahi, L; McIntosh, N; Turetta, N; Bardini, M; Giannini, S; Ruzié, C; Schweicher, G; Beljonne, D; Cornil, J; Samorì, P; Mas-Torrent, M; Geerts, Y H; Modena, E; Maini, L From synthesis to device fabrication: elucidating the structural and electronic properties of C7-BTBT-C7 Journal Article In: J. Mater. Chem. C, 2023, , 11 (7345–7355 ), 2023. @article{Pandey2023, title = {From synthesis to device fabrication: elucidating the structural and electronic properties of C7-BTBT-C7}, author = {P. Pandey and L. Fijahi and N. McIntosh and N. Turetta and M. Bardini and S. Giannini and C. Ruzié and G. Schweicher and D. Beljonne and J. Cornil and P. Samorì and M. Mas-Torrent and Y. H. Geerts and E. Modena and L. Maini}, url = {https://doi.org/10.1039/d3tc00434a}, year = {2023}, date = {2023-04-21}, journal = {J. Mater. Chem. C, 2023, }, volume = {11}, number = {7345–7355 }, abstract = {We report the polymorph investigation, crystallographic study and fabrication of organic field-effect transistors (OFETs) in solution-processed thin films of a prototypical organic semiconductor, i.e., 2,7-diheptylbenzo[b]benzo[4,5]thieno[2,3-d]thiophene (C7-BTBT-C7). We found that this molecule self-assembles solely into one type of stable crystal form, regardless of the experimental conditions employed when using conventional and non-conventional methods of crystallization. The integration of blends of C7-BTBT-C7 with polystyrene as active materials in OFETs fabricated using a solution shearing technique led to a field-effect mobility of 1.42 ± 0.45 cm2 V−1 s−1 in the saturation regime when a coating speed of 10 mm s−1 was employed. The intrinsic structural properties control the overlap of the frontier orbitals, thereby affecting the device performance. The interplay between the crystal packing, thin film morphology and uniformity and its impact on the device performance are reported.}, keywords = {}, pubstate = {published}, tppubtype = {article} } We report the polymorph investigation, crystallographic study and fabrication of organic field-effect transistors (OFETs) in solution-processed thin films of a prototypical organic semiconductor, i.e., 2,7-diheptylbenzo[b]benzo[4,5]thieno[2,3-d]thiophene (C7-BTBT-C7). We found that this molecule self-assembles solely into one type of stable crystal form, regardless of the experimental conditions employed when using conventional and non-conventional methods of crystallization. The integration of blends of C7-BTBT-C7 with polystyrene as active materials in OFETs fabricated using a solution shearing technique led to a field-effect mobility of 1.42 ± 0.45 cm2 V−1 s−1 in the saturation regime when a coating speed of 10 mm s−1 was employed. The intrinsic structural properties control the overlap of the frontier orbitals, thereby affecting the device performance. The interplay between the crystal packing, thin film morphology and uniformity and its impact on the device performance are reported. |
Ippolito, S; Urban, F; Zheng, W; Mazzarisi, O; Valentini, C; Kelly, A G; Gali, S M; Bonn, M; Beljonne, D; Corberi, F; Coleman, J N; Wang, H I; Samorì, P Unveiling Charge-Transport Mechanisms in Electronic Devices Based on Defect-Engineered MoS2 Covalent Networks Journal Article In: Adv. Mater., 35 (2211157), 2023. @article{Ippolito2023, title = {Unveiling Charge-Transport Mechanisms in Electronic Devices Based on Defect-Engineered MoS2 Covalent Networks}, author = {S. Ippolito and F. Urban and W. Zheng and O. Mazzarisi and C. Valentini and A. G. Kelly and S. M. Gali and M. Bonn and D. Beljonne and F. Corberi and J. N. Coleman and H. I. Wang and P. Samorì}, editor = {Wiley Online Library}, url = {https://doi.org/10.1002/adma.202211157}, year = {2023}, date = {2023-04-13}, journal = {Adv. Mater.}, volume = {35}, number = {2211157}, abstract = {Device performance of solution-processed 2D semiconductors in printed electronics has been limited so far by structural defects and high interflake junction resistance. Covalently interconnected networks of transition metal dichalcogenides potentially represent an efficient strategy to overcome both limitations simultaneously. Yet, the charge-transport properties in such systems have not been systematically researched. Here, the charge-transport mechanisms of printed devices based on covalent MoS2 networks are unveiled via multiscale analysis, comparing the effects of aromatic versus aliphatic dithiolated linkers. Temperature-dependent electrical measurements reveal hopping as the dominant transport mechanism: aliphatic systems lead to 3D variable range hopping, unlike the nearest neighbor hopping observed for aromatic linkers. The novel analysis based on percolation theory attributes the superior performance of devices functionalized with π-conjugated molecules to the improved interflake electronic connectivity and formation of additional percolation paths, as further corroborated by density functional calculations. Valuable guidelines for harnessing the charge-transport properties in MoS2 devices based on covalent networks are provided.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Device performance of solution-processed 2D semiconductors in printed electronics has been limited so far by structural defects and high interflake junction resistance. Covalently interconnected networks of transition metal dichalcogenides potentially represent an efficient strategy to overcome both limitations simultaneously. Yet, the charge-transport properties in such systems have not been systematically researched. Here, the charge-transport mechanisms of printed devices based on covalent MoS2 networks are unveiled via multiscale analysis, comparing the effects of aromatic versus aliphatic dithiolated linkers. Temperature-dependent electrical measurements reveal hopping as the dominant transport mechanism: aliphatic systems lead to 3D variable range hopping, unlike the nearest neighbor hopping observed for aromatic linkers. The novel analysis based on percolation theory attributes the superior performance of devices functionalized with π-conjugated molecules to the improved interflake electronic connectivity and formation of additional percolation paths, as further corroborated by density functional calculations. Valuable guidelines for harnessing the charge-transport properties in MoS2 devices based on covalent networks are provided. |
Zheng, H; Ou, C; Huang, X; Jiang, B; Li, W; Li, J; Han, X; Liu, C; Han, Z; Ji, T; Samorì, P; Zhang, L A Flexible, High-Voltage (>100 V) Generating Device Based on Zebra-Like Asymmetrical Photovoltaic Cascade Journal Article In: Adv. Mater., 35 (2209482 ), 2023. @article{Zheng2023, title = {A Flexible, High-Voltage (>100 V) Generating Device Based on Zebra-Like Asymmetrical Photovoltaic Cascade}, author = {H. Zheng and C. Ou and X. Huang and B. Jiang and W. Li and J. Li and X. Han and C. Liu and Z. Han and T. Ji and P. Samorì and L. Zhang}, editor = {Wiley Online Library}, url = {https://doi.org/10.1002/adma.202209482}, year = {2023}, date = {2023-03-09}, journal = {Adv. Mater.}, volume = {35}, number = {2209482 }, abstract = {The mutual conversion between light and electricity lies at the heart of optoelectronic and photonic applications. Maximization of the photoelectric conversion is a long-term goal that can be pursued via the fabrication of devices with ad-hoc architectures. In this framework, it is of utter importance to harvest and transform light irradiation into high electric potential in specific area for driving functional dielectrics that respond to pure electric field. Here, a nano-fabrication technology has been devised featuring double self-alignment that is applied to construct zebra-like asymmetric heterojunction arrays. Such nanostructured composite, which covers a surface area of 5 × 4 mm2 and contains 500 periodic repeating units, is capable of photo generating voltages as high as 140 V on a flexible substrate. This approach represents a leap over the traditional functionalization process based on simply embedding materials into devices by demonstrating the disruptive potential of integrating oriented nanoscale device components into meta-material.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The mutual conversion between light and electricity lies at the heart of optoelectronic and photonic applications. Maximization of the photoelectric conversion is a long-term goal that can be pursued via the fabrication of devices with ad-hoc architectures. In this framework, it is of utter importance to harvest and transform light irradiation into high electric potential in specific area for driving functional dielectrics that respond to pure electric field. Here, a nano-fabrication technology has been devised featuring double self-alignment that is applied to construct zebra-like asymmetric heterojunction arrays. Such nanostructured composite, which covers a surface area of 5 × 4 mm2 and contains 500 periodic repeating units, is capable of photo generating voltages as high as 140 V on a flexible substrate. This approach represents a leap over the traditional functionalization process based on simply embedding materials into devices by demonstrating the disruptive potential of integrating oriented nanoscale device components into meta-material. |
Pilato, S; Moffa, S; Siani, G; Diomede, F; Trubiani, O; Pizzicannella, J; Capista, D; Passacantando, M; Samorì, P; Fontana, A 3D Graphene Oxide-Polyethylenimine Scaffolds for Cardiac Tissue Engineering Journal Article In: Mater. Interfaces, 15 , pp. 14077–14088, 2023. @article{Pilato2023, title = {3D Graphene Oxide-Polyethylenimine Scaffolds for Cardiac Tissue Engineering}, author = {S. Pilato and S. Moffa and G. Siani and F. Diomede and O. Trubiani and J. Pizzicannella and D. Capista and M. Passacantando and P. Samorì and A. Fontana}, editor = {ACS Publcation}, url = {https://pubs.acs.org/doi/10.1021/acsami.3c00216}, year = {2023}, date = {2023-03-07}, journal = {Mater. Interfaces}, volume = {15}, pages = {14077–14088}, abstract = {The development of novel three-dimensional (3D) nanomaterials combining high biocompatibility, precise mechanical characteristics, electrical conductivity, and controlled pore size to enable cell and nutrient permeation is highly sought after for cardiac tissue engineering applications including repair of damaged heart tissues following myocardial infarction and heart failure. Such unique characteristics can collectively be found in hybrid, highly porous tridimensional scaffolds based on chemically functionalized graphene oxide (GO). By exploiting the rich reactivity of the GO’s basal epoxydic and edge carboxylate moieties when interacting, respectively, with NH2 and NH3+ groups of linear polyethylenimines (PEIs), 3D architectures with variable thickness and porosity can be manufactured, making use of the layer-by-layer technique through the subsequent dipping in GO and PEI aqueous solutions, thereby attaining enhanced compositional and structural control. The elasticity modulus of the hybrid material is found to depend on scaffold’s thickness, with the lowest value of 13 GPa obtained in samples containing the highest number of alternating layers. Thanks to the amino-rich composition of the hybrid and the established biocompatibility of GO, the scaffolds do not exhibit cytotoxicity; they promote cardiac muscle HL-1 cell adhesion and growth without interfering with the cell morphology and increasing cardiac markers such as Connexin-43 and Nkx 2.5. Our novel strategy for scaffold preparation thus overcomes the drawbacks associated with the limited processability of pristine graphene and low GO conductivity, and it enables the production of biocompatible 3D GO scaffolds covalently functionalized with amino-based spacers, which is advantageous for cardiac tissue engineering applications. In particular, they displayed a significant increase in the number of gap junctions compared to HL-1 cultured on CTRL substrates, which render them key components for repairing damaged heart tissues as well as being used for 3D in vitro cardiac modeling investigations.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The development of novel three-dimensional (3D) nanomaterials combining high biocompatibility, precise mechanical characteristics, electrical conductivity, and controlled pore size to enable cell and nutrient permeation is highly sought after for cardiac tissue engineering applications including repair of damaged heart tissues following myocardial infarction and heart failure. Such unique characteristics can collectively be found in hybrid, highly porous tridimensional scaffolds based on chemically functionalized graphene oxide (GO). By exploiting the rich reactivity of the GO’s basal epoxydic and edge carboxylate moieties when interacting, respectively, with NH2 and NH3+ groups of linear polyethylenimines (PEIs), 3D architectures with variable thickness and porosity can be manufactured, making use of the layer-by-layer technique through the subsequent dipping in GO and PEI aqueous solutions, thereby attaining enhanced compositional and structural control. The elasticity modulus of the hybrid material is found to depend on scaffold’s thickness, with the lowest value of 13 GPa obtained in samples containing the highest number of alternating layers. Thanks to the amino-rich composition of the hybrid and the established biocompatibility of GO, the scaffolds do not exhibit cytotoxicity; they promote cardiac muscle HL-1 cell adhesion and growth without interfering with the cell morphology and increasing cardiac markers such as Connexin-43 and Nkx 2.5. Our novel strategy for scaffold preparation thus overcomes the drawbacks associated with the limited processability of pristine graphene and low GO conductivity, and it enables the production of biocompatible 3D GO scaffolds covalently functionalized with amino-based spacers, which is advantageous for cardiac tissue engineering applications. In particular, they displayed a significant increase in the number of gap junctions compared to HL-1 cultured on CTRL substrates, which render them key components for repairing damaged heart tissues as well as being used for 3D in vitro cardiac modeling investigations. |
Peng, H; Huang, S; Montes-García, V; Pakulski, D; Guo, H; Richard, F; Zhuang, X; Samorì, P; Peng, CiesielskiH. A; Huang, S; Montes-García, V; Pakulski, D; Guo, H; Richard, F; Zhuang, X; Samorì, P; Ciesielski, A In: Angew. Chem. Int. , 62 (e202216136), 2023. @article{Peng2023b, title = {Supramolecular Engineering of Cathode Materials for Aqueous Zinc-ion Energy Storage Devices: Novel Benzothiadiazole Functionalized Two-Dimensional Olefin-Linked COFs}, author = {H. Peng and S. Huang and V. Montes-García and D. Pakulski and H. Guo and F. Richard and X. Zhuang and P. Samorì and A. CiesielskiH. Peng and S. Huang and V. Montes-García and D. Pakulski and H. Guo and F. Richard and X. Zhuang and P. Samorì and A. Ciesielski}, editor = {Wiley Online Library}, url = {https://doi.org/10.1002/anie.202216136}, year = {2023}, date = {2023-03-01}, journal = {Angew. Chem. Int. }, volume = {62}, number = {e202216136}, abstract = {Two-dimensional covalent organic frameworks (COFs) have emerged as promising materials for energy storage applications exhibiting enhanced electrochemical performance...}, keywords = {}, pubstate = {published}, tppubtype = {article} } Two-dimensional covalent organic frameworks (COFs) have emerged as promising materials for energy storage applications exhibiting enhanced electrochemical performance... |
Turetta, N; Danowski, W; Cusin, L; Livio, P A; Hallani, R; McCulloch, I; and S. Lara Avila, Samorì P A photo-responsive organic electrochemical transistor Journal Article In: J. Mater. Chem. C, 11 , pp. 7982–7988, 2023. @article{Turetta2023, title = {A photo-responsive organic electrochemical transistor}, author = {N. Turetta and W. Danowski and L. Cusin and P. A. Livio and R. Hallani and I. McCulloch and S. Lara Avila ,and P. Samorì}, editor = {Royal Society of Chemistry}, url = {https://doi.org/10.1039/d2tc05444b}, year = {2023}, date = {2023-02-28}, journal = {J. Mater. Chem. C}, volume = {11}, pages = {7982–7988}, abstract = {The design of novel organic electrochemical transistor (OECT) channel materials that can be controlled by a whole range of external stimuli is key towards the emergence of unprecedented technologies in bioelectronics. Like the established multiresponsive field-effect transistors, multiresponsive OECTs can in principle be realised via blending, by combining multiple components with each one imparting a specific function to the device. Here we report the first example of an optically switchable OECT which is capable of undergoing a reversible modulation of its ON current by up to 30% upon irradiation with UV and visible light. By investigating the electrical characteristics of the channel material, in conjunction with the electronic characterisation performed by a macroscopic Kelvin probe technique and photoemission yield spectroscopy in air, we gained distinct insight into the electrochemical doping process occurring within the blend upon light irradiation. Such a proof-of-concept work opens perspectives towards the implementation of complex neuromorphic operations and algorithms in OECTs.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The design of novel organic electrochemical transistor (OECT) channel materials that can be controlled by a whole range of external stimuli is key towards the emergence of unprecedented technologies in bioelectronics. Like the established multiresponsive field-effect transistors, multiresponsive OECTs can in principle be realised via blending, by combining multiple components with each one imparting a specific function to the device. Here we report the first example of an optically switchable OECT which is capable of undergoing a reversible modulation of its ON current by up to 30% upon irradiation with UV and visible light. By investigating the electrical characteristics of the channel material, in conjunction with the electronic characterisation performed by a macroscopic Kelvin probe technique and photoemission yield spectroscopy in air, we gained distinct insight into the electrochemical doping process occurring within the blend upon light irradiation. Such a proof-of-concept work opens perspectives towards the implementation of complex neuromorphic operations and algorithms in OECTs. |
Buriak, J M; Akinwande, D; Artzi, N; Brinker, C J; Burrows, C; Chan, W C W; Chen, C; Chen, X; Chhowalla, M; Chi, L; Chueh, W; Crudden, C M; Carlo, Di D; Glotzer, S C; Hersam, M C; Ho, D; Hu, T Y; Huang, J; Javey, A; Kamat, P V; Kim, I -D; Kotov, N A; Lee, T R; Lee, Y H; Li, Y; Liz-Marzán, L M; Mulvaney, P; Narang, P; Nordlander, P; Oklu, R; Parak, W J; Rogach, A L; Salanne, M; Samorì, P; Schaak, R E; Schanze, K S; Sekitani, T; Skrabalak, S; Sood, A K; Voets, I K; Wang, S; Wang, S; Wee, A T S; Ye, J Best Practices for Using AI When Writing Scientific Manuscripts – Caution, Care, and Consideration: Creative Science Depends on It Journal Article In: ACS Nano, 2023, ACS Nano (17), pp. 4091–4093, 2023. @article{Buriak2023, title = {Best Practices for Using AI When Writing Scientific Manuscripts – Caution, Care, and Consideration: Creative Science Depends on It}, author = {J. M. Buriak and D. Akinwande and N. Artzi and C. J. Brinker and C. Burrows and W. C. W. Chan and C. Chen and X. Chen and M. Chhowalla and L. Chi and W. Chueh and C. M. Crudden and D. Di Carlo and S. C. Glotzer and M. C. Hersam and D. Ho and T. Y. Hu and J. Huang and A. Javey and P. V. Kamat and I.-D. Kim and N. A. Kotov and T. R. Lee and Y. H. Lee and Y. Li and L. M. Liz-Marzán and P. Mulvaney and P. Narang and P. Nordlander and R. Oklu and W. J. Parak and A. L. Rogach and M. Salanne and P. Samorì and R. E. Schaak and K. S. Schanze and T. Sekitani and S. Skrabalak and A. K. Sood and I. K. Voets and S. Wang and S. Wang and A. T. S. Wee and J. Ye}, editor = {ACS Publcation}, url = {https://doi.org/10.1021/acsnano.3c01544}, year = {2023}, date = {2023-02-27}, journal = {ACS Nano, 2023}, volume = {ACS Nano}, number = {17}, pages = {4091–4093}, abstract = {Science is communicated through language. The media of language in science is multimodal, ranging from lecturing in classrooms, to informal daily discussions among scientists, to prepared talks at conferences, and, finally, to the pinnacle of science communication, the formal peer-reviewed publication. The arrival of language tools driven by artificial intelligence (AI), like ChatGPT, (1) has generated an explosion of interest globally. ChatGPT has set the record for the fastest growing user base of any application in history, with over 100 million active users in just two months, as of the end of January 2023. (2) ChatGPT is merely the first of many AI-based language tools, with announcements of more either in preparation or soon to be launched. (3−5) Many in scientific research and universities around the world have raised concerns of ChatGPT‘s potential to transform scientific communication (6) before we have had time to consider the ramifications of such a tool or verified that the text it generates is factually correct. The human-like quality of the text structure produced by ChatGPT can deceive readers into believing it is of human origin. (7) It is now apparent, however, that the generated text might be fraught with errors, can be shallow and superficial, and can generate false journal references and inferences. (8) More importantly, ChatGPT sometimes makes connections that are nonsensical and false. We have prepared a brief summary of some of the strengths and weaknesses of ChatGPT (and future AI language bots) and conclude with a set of our recommendations of best practices for scientists when using such tools at any stage of their research, particularly at the manuscript writing stage. (9,10) It is important to state that even among the authors here, there is a diversity of thought and opinion, and this editorial reflects the middle ground consensus. In its current incarnation, ChatGPT is merely an efficient language bot that generates text by linguistic connections. (11) It is, at present, “just a giant autocomplete machine”. (12) Since ChatGPT is the first of many models that will undoubtedly improve rapidly, within a few years we will almost certainly look back at ChatGPT like an old computer from the 1980s. It must be recognized that ChatGPT relies on its existing database and content and, at the time of writing of this editorial, fails to include information published or posted after 2021, thus restricting its utility when applied to the writing of up-to-date reviews, perspectives, and introductions. Therefore, for reviews and perspectives, ChatGPT is deficient due to its lack of analytical capabilities that scientists are expected to possess and the experiences that inform us.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Science is communicated through language. The media of language in science is multimodal, ranging from lecturing in classrooms, to informal daily discussions among scientists, to prepared talks at conferences, and, finally, to the pinnacle of science communication, the formal peer-reviewed publication. The arrival of language tools driven by artificial intelligence (AI), like ChatGPT, (1) has generated an explosion of interest globally. ChatGPT has set the record for the fastest growing user base of any application in history, with over 100 million active users in just two months, as of the end of January 2023. (2) ChatGPT is merely the first of many AI-based language tools, with announcements of more either in preparation or soon to be launched. (3−5) Many in scientific research and universities around the world have raised concerns of ChatGPT‘s potential to transform scientific communication (6) before we have had time to consider the ramifications of such a tool or verified that the text it generates is factually correct. The human-like quality of the text structure produced by ChatGPT can deceive readers into believing it is of human origin. (7) It is now apparent, however, that the generated text might be fraught with errors, can be shallow and superficial, and can generate false journal references and inferences. (8) More importantly, ChatGPT sometimes makes connections that are nonsensical and false. We have prepared a brief summary of some of the strengths and weaknesses of ChatGPT (and future AI language bots) and conclude with a set of our recommendations of best practices for scientists when using such tools at any stage of their research, particularly at the manuscript writing stage. (9,10) It is important to state that even among the authors here, there is a diversity of thought and opinion, and this editorial reflects the middle ground consensus. In its current incarnation, ChatGPT is merely an efficient language bot that generates text by linguistic connections. (11) It is, at present, “just a giant autocomplete machine”. (12) Since ChatGPT is the first of many models that will undoubtedly improve rapidly, within a few years we will almost certainly look back at ChatGPT like an old computer from the 1980s. It must be recognized that ChatGPT relies on its existing database and content and, at the time of writing of this editorial, fails to include information published or posted after 2021, thus restricting its utility when applied to the writing of up-to-date reviews, perspectives, and introductions. Therefore, for reviews and perspectives, ChatGPT is deficient due to its lack of analytical capabilities that scientists are expected to possess and the experiences that inform us. |
Valentini, C; Montes-García, V; Livio, P A; Chudziak, T; Raya, J; Ciesielski, A; Samorì, P Tuning the electrical properties of graphene oxide through low-temperature thermal annealing Journal Article In: Nanoscale, 15 , pp. 5743–5755 , 2023. @article{Valentini2023, title = {Tuning the electrical properties of graphene oxide through low-temperature thermal annealing}, author = {C. Valentini and V. Montes-García and P. A. Livio and T. Chudziak and J. Raya and A. Ciesielski and P. Samorì}, editor = {Royal Society of Chemistry}, url = {https://doi.org/10.1039/d2nr06091d}, year = {2023}, date = {2023-02-16}, journal = {Nanoscale}, volume = {15}, pages = {5743–5755 }, abstract = {During the last fifteen years, the reduction of electrically insulating graphene oxide (GO) through the elimination of oxygen containing functional groups and the restoration of sp2 conjugation yielding its conducting form, known as reduced graphene oxide (rGO), has been widely investigated as a scalable and low-cost method to produce materials featuring graphene-like characteristics. Among various protocols, thermal annealing represents an attractive green approach compatible with industrial processes. However, the high temperatures typically required to accomplish this process are energetically demanding and are incompatible with the use of plastic substrates often desired for flexible electronics applications. Here, we report a systematic study on the low-temperature annealing of GO by optimizing different annealing conditions, i.e., temperature, time, and reduction atmosphere. We show that the reduction is accompanied by structural changes of GO, which affect its electrochemical performance when used as an electrode material in supercapacitors. We demonstrate that thermally-reduced GO (TrGO) obtained under air or inert atmosphere at relatively low temperatures (<300 °C) exhibits low film resistivities (10−2–10−4 Ω m) combined with unaltered resistance after 2000 bending cycles when supported on plastic substrates. Moreover, it exhibits enhanced electrochemical characteristics with a specific capacitance of 208 F g−1 and a capacitance retention of >99% after 2000 cycles. The reported strategy is an important step forward toward the development of environmentally friendly TrGO for future electrical or electrochemical applications.}, keywords = {}, pubstate = {published}, tppubtype = {article} } During the last fifteen years, the reduction of electrically insulating graphene oxide (GO) through the elimination of oxygen containing functional groups and the restoration of sp2 conjugation yielding its conducting form, known as reduced graphene oxide (rGO), has been widely investigated as a scalable and low-cost method to produce materials featuring graphene-like characteristics. Among various protocols, thermal annealing represents an attractive green approach compatible with industrial processes. However, the high temperatures typically required to accomplish this process are energetically demanding and are incompatible with the use of plastic substrates often desired for flexible electronics applications. Here, we report a systematic study on the low-temperature annealing of GO by optimizing different annealing conditions, i.e., temperature, time, and reduction atmosphere. We show that the reduction is accompanied by structural changes of GO, which affect its electrochemical performance when used as an electrode material in supercapacitors. We demonstrate that thermally-reduced GO (TrGO) obtained under air or inert atmosphere at relatively low temperatures (<300 °C) exhibits low film resistivities (10−2–10−4 Ω m) combined with unaltered resistance after 2000 bending cycles when supported on plastic substrates. Moreover, it exhibits enhanced electrochemical characteristics with a specific capacitance of 208 F g−1 and a capacitance retention of >99% after 2000 cycles. The reported strategy is an important step forward toward the development of environmentally friendly TrGO for future electrical or electrochemical applications. |
Peng, H; Montes-García, V; Raya, J; Wang, H; Guo, H; Richard, F; Samorì, P; Ciesielski, A In: J. Mater. Chem. A, 11 , pp. 2718–2725, 2023. @article{Peng2023, title = {Supramolecular engineering of cathode materials for aqueous zinc-ion hybrid supercapacitors: novel thiophene-bridged donor–acceptor sp2 carbon-linked polymers}, author = {H. Peng and V. Montes-García and J. Raya and H. Wang and H. Guo and F. Richard and P. Samorì and A. Ciesielski}, editor = {Royal Society of Chemistry}, url = {https://doi.org/10.1039/d2ta09651j}, year = {2023}, date = {2023-01-18}, journal = {J. Mater. Chem. A}, volume = {11}, pages = {2718–2725}, abstract = {Rechargeable aqueous zinc-ion hybrid supercapacitors (Zn-HSCs) are promising candidates as large-scale energy storage devices owing to their high electrochemical performance, safety, long life, and low price. The development of nanostructured electrode materials featuring multiple active sites capable of interacting with Zn ions represents an efficient strategy to boost their electrochemical performance. In this work, we report for the first time the use of donor–acceptor carbon-linked conjugated polymers (DA-CCPs) as cathodes in aqueous Zn-HSCs. We have synthesized two novel DA-CCPs via Knoevenagel polymerization between electron-accepting 2,2′,2′′-(benzene-1,3,5-triyl)triacetonitrile and electron-donating 2,5-thiophene dicarboxaldehyde or [2,2′-bithiophene]-5,5′-dicarboxaldehyde, yielding DA-CCP-1 and DA-CCP-2, respectively. DA-CCP-2, which possesses an extra-thiophene unit in the backbone, exhibits improved electrochemical characteristics when compared to DA-CCP-1, and performance surpassing those of other reported cathode materials for aqueous Zn2+ energy storage systems. DA-CCP-1 and -2 based electrodes exhibited an outstanding energy density of 80.6 and 196.3 W h kg−1 respectively, representing the highest value ever reached for conjugated polymers to date. This study not only offers new perspectives for the rational design and precise synthesis of DA-CCPs but it also broadens the choice of cathodes for high-performance aqueous Zn-HSCs.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Rechargeable aqueous zinc-ion hybrid supercapacitors (Zn-HSCs) are promising candidates as large-scale energy storage devices owing to their high electrochemical performance, safety, long life, and low price. The development of nanostructured electrode materials featuring multiple active sites capable of interacting with Zn ions represents an efficient strategy to boost their electrochemical performance. In this work, we report for the first time the use of donor–acceptor carbon-linked conjugated polymers (DA-CCPs) as cathodes in aqueous Zn-HSCs. We have synthesized two novel DA-CCPs via Knoevenagel polymerization between electron-accepting 2,2′,2′′-(benzene-1,3,5-triyl)triacetonitrile and electron-donating 2,5-thiophene dicarboxaldehyde or [2,2′-bithiophene]-5,5′-dicarboxaldehyde, yielding DA-CCP-1 and DA-CCP-2, respectively. DA-CCP-2, which possesses an extra-thiophene unit in the backbone, exhibits improved electrochemical characteristics when compared to DA-CCP-1, and performance surpassing those of other reported cathode materials for aqueous Zn2+ energy storage systems. DA-CCP-1 and -2 based electrodes exhibited an outstanding energy density of 80.6 and 196.3 W h kg−1 respectively, representing the highest value ever reached for conjugated polymers to date. This study not only offers new perspectives for the rational design and precise synthesis of DA-CCPs but it also broadens the choice of cathodes for high-performance aqueous Zn-HSCs. |
2022 |
Miao, J; Wu, L; Bian, Z; Zhu, Q; Zhang, T; Pan, X; Hu, J; Xu, W; Wang, Y; Xu, Y; Yu, B; Ji, W; Zhang, X; Qiao, J; P. Samorì, Zhao Y A “Click” Reaction to Engineer MoS2 Field-Effect Transistors with Low Contact Resistance Journal Article In: ACS Nano, pp. 20647–20655, 2022. @article{Miao2023, title = {A “Click” Reaction to Engineer MoS2 Field-Effect Transistors with Low Contact Resistance}, author = {J. Miao and L. Wu and Z. Bian and Q. Zhu and T. Zhang and X. Pan and J. Hu and W. Xu and Y. Wang and Y. Xu and B. Yu and W. Ji and X. Zhang and J. Qiao and P. Samorì, Y. Zhao}, editor = {ACS Publcation}, url = {https://doi.org/10.1021/acsnano.2c07670}, year = {2022}, date = {2022-12-16}, journal = {ACS Nano}, pages = {20647–20655}, abstract = {Two-dimensional (2D) materials with the atomically thin thickness have attracted great interest in the post-Moore’s Law era because of their tremendous potential to continue transistor downscaling and offered advances in device performance at the atomic limit. However, the metal–semiconductor contact is the bottleneck in field-effect transistors (FETs) integrating 2D semiconductors as channel materials. A robust and tunable doping method at the source and drain region of 2D transistors to minimize the contact resistance is highly sought after. Here we report a stable carrier doping method via the mild covalent grafting of maleimides on the surface of 2D transition metal dichalcogenides. The chemisorbed interaction contributes to the efficient carrier doping without degrading the high-performance carrier transport. Density functional theory results further illustrate that the molecular functionalization leads to the mild hybridization and the negligible impact on the conduction bands of monolayer MoS2, avoiding the random scattering from the dopants. Differently from reported molecular treatments, our strategy displays high thermal stability (above 300 °C) and it is compatible with micro/nano processing technology. The contact resistance of MoS2 FETs can be greatly reduced by ∼12 times after molecular functionalization. The Schottky barrier of 44 meV is achieved on monolayer MoS2 FETs, demonstrating efficient charge injection between metal and 2D semiconductor. The mild covalent functionalization of molecules on 2D semiconductors represents a powerful strategy to perform the carrier doping and the device optimization.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Two-dimensional (2D) materials with the atomically thin thickness have attracted great interest in the post-Moore’s Law era because of their tremendous potential to continue transistor downscaling and offered advances in device performance at the atomic limit. However, the metal–semiconductor contact is the bottleneck in field-effect transistors (FETs) integrating 2D semiconductors as channel materials. A robust and tunable doping method at the source and drain region of 2D transistors to minimize the contact resistance is highly sought after. Here we report a stable carrier doping method via the mild covalent grafting of maleimides on the surface of 2D transition metal dichalcogenides. The chemisorbed interaction contributes to the efficient carrier doping without degrading the high-performance carrier transport. Density functional theory results further illustrate that the molecular functionalization leads to the mild hybridization and the negligible impact on the conduction bands of monolayer MoS2, avoiding the random scattering from the dopants. Differently from reported molecular treatments, our strategy displays high thermal stability (above 300 °C) and it is compatible with micro/nano processing technology. The contact resistance of MoS2 FETs can be greatly reduced by ∼12 times after molecular functionalization. The Schottky barrier of 44 meV is achieved on monolayer MoS2 FETs, demonstrating efficient charge injection between metal and 2D semiconductor. The mild covalent functionalization of molecules on 2D semiconductors represents a powerful strategy to perform the carrier doping and the device optimization. |
Wang, H; Chen, Y; Ni, Z; Samorì, P An Electrochemical-Electret Coupled Organic Synapse with Single-Polarity Driven Reversible Facilitation-to-Depression Switching Journal Article In: Adv. Mater., 34 (2205945), 2022. @article{Wang2022b, title = {An Electrochemical-Electret Coupled Organic Synapse with Single-Polarity Driven Reversible Facilitation-to-Depression Switching}, author = {H. Wang and Y. Chen and Z. Ni and P. Samorì}, editor = {Wiley Online Library}, url = {https://doi.org/10.1002/adma.202205945}, year = {2022}, date = {2022-12-15}, journal = {Adv. Mater.}, volume = {34}, number = {2205945}, abstract = {Neuromorphic engineering and artificial intelligence demands hardware elements that emulates synapse algorithms. During the last decade electrolyte-gated organic conjugated materials have been explored as a platform for artificial synapses for neuromorphic computing. Unlike biological synapses, in current devices the synaptic facilitation and depression are triggered by voltages with opposite polarity. To enhance the reliability and simplify the operation of the synapse without lowering its sophisticated functionality, here, an electrochemical-electret coupled organic synapse (EECS) possessing a reversible facilitation-to-depression switch, is devised. Electret charging counterbalances channel conductance changes due to electrochemical doping, inducing depression without inverting the gate polarity. Overall, EECS functions as a threshold-controlled synaptic switch ruled by its amplitude-dependent, dual-modal operation, which can well emulate information storage and erase as in real synapses. By varying the energy level offset between the channel material and the electret, the EECS's transition threshold can be adjusted for specific applications, e.g., imparting additional light responsiveness to the device operation. The novel device architecture represents a major step forward in the development of artificial organic synapses with increased functional complexity and it opens new perspectives toward the fabrication of abiotic neural networks with higher reliability, efficiency, and endurance.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Neuromorphic engineering and artificial intelligence demands hardware elements that emulates synapse algorithms. During the last decade electrolyte-gated organic conjugated materials have been explored as a platform for artificial synapses for neuromorphic computing. Unlike biological synapses, in current devices the synaptic facilitation and depression are triggered by voltages with opposite polarity. To enhance the reliability and simplify the operation of the synapse without lowering its sophisticated functionality, here, an electrochemical-electret coupled organic synapse (EECS) possessing a reversible facilitation-to-depression switch, is devised. Electret charging counterbalances channel conductance changes due to electrochemical doping, inducing depression without inverting the gate polarity. Overall, EECS functions as a threshold-controlled synaptic switch ruled by its amplitude-dependent, dual-modal operation, which can well emulate information storage and erase as in real synapses. By varying the energy level offset between the channel material and the electret, the EECS's transition threshold can be adjusted for specific applications, e.g., imparting additional light responsiveness to the device operation. The novel device architecture represents a major step forward in the development of artificial organic synapses with increased functional complexity and it opens new perspectives toward the fabrication of abiotic neural networks with higher reliability, efficiency, and endurance. |
Hou, H -L; Anichini, C; Samorì, P; Criado, A; Prato, M 2D Van der Waals Heterostructures for Chemical Sensing Journal Article In: Adv. Funct. Mater., 32 (2207065), 2022. @article{Hou2022, title = {2D Van der Waals Heterostructures for Chemical Sensing}, author = {H.-L. Hou and C. Anichini and P. Samorì and A. Criado and M. Prato}, editor = {Wiley Online Library}, url = {https://doi.org/10.1002/adfm.202207065}, year = {2022}, date = {2022-12-02}, journal = {Adv. Funct. Mater.}, volume = {32}, number = {2207065}, abstract = {During the last 15 years, 2D materials have revolutionized the field of materials science. Moreover, because of their highest surface-to-volume ratio and properties extremely susceptible to their interaction with the local environment they became powerful active components for the development the high-performance chemical sensors. By combining different 2D materials to form van der Waals heterostructures (VDWHs) it is possible to overcome the drawback of individual materials (such as inertness and zero-bandgap of pristine graphene and less environmental stability of transition metal dichalcogenides). Meanwhile, VDWHs possess unprecedented and fascinating properties arising from the intimate interaction between the components, which can yield superior sensitivities, higher selectivity, and stability when employed to detect gases, biomolecules, and other organic/inorganic molecules. Herein, the latest developments and advances in the field of chemical sensors based on VDWH of 2D materials, with specific insight into the sensing mechanisms, are reviewed and future directions, challenges, and opportunities for the development of the next generation of (bio)chemical sensors with potential impact in environmental sciences and biomedical applications, and more specifically in (bio)chemical defense, industrial safety, food, and environmental surveillance, and medical (early) diagnostics, are discussed.}, keywords = {}, pubstate = {published}, tppubtype = {article} } During the last 15 years, 2D materials have revolutionized the field of materials science. Moreover, because of their highest surface-to-volume ratio and properties extremely susceptible to their interaction with the local environment they became powerful active components for the development the high-performance chemical sensors. By combining different 2D materials to form van der Waals heterostructures (VDWHs) it is possible to overcome the drawback of individual materials (such as inertness and zero-bandgap of pristine graphene and less environmental stability of transition metal dichalcogenides). Meanwhile, VDWHs possess unprecedented and fascinating properties arising from the intimate interaction between the components, which can yield superior sensitivities, higher selectivity, and stability when employed to detect gases, biomolecules, and other organic/inorganic molecules. Herein, the latest developments and advances in the field of chemical sensors based on VDWH of 2D materials, with specific insight into the sensing mechanisms, are reviewed and future directions, challenges, and opportunities for the development of the next generation of (bio)chemical sensors with potential impact in environmental sciences and biomedical applications, and more specifically in (bio)chemical defense, industrial safety, food, and environmental surveillance, and medical (early) diagnostics, are discussed. |
Romito, D; Fresta, E; Cavinato, L M; Kählig, H; Amenitsch, H; Caputo, L; Chen, Y; Samorì, P; Charlier, J -C; Costa, R; Bonifazi, D Supramolecular Chalcogen-Bonded Semiconducting Nanoribbons at Work in Lighting Devices Journal Article In: Angew. Chem. Int. Ed., 61 (e202202137), 2022. @article{Romito2022, title = {Supramolecular Chalcogen-Bonded Semiconducting Nanoribbons at Work in Lighting Devices}, author = {D. Romito and E. Fresta and L. M. Cavinato and H. Kählig and H. Amenitsch and L. Caputo and Y. Chen and P. Samorì and J.-C. Charlier and R. Costa and D. Bonifazi}, editor = {Wiley Online Library}, url = {https://doi.org/10.1002/anie.202202137}, year = {2022}, date = {2022-09-19}, journal = {Angew. Chem. Int. Ed.}, volume = {61}, number = {e202202137}, abstract = {This work describes the design and synthesis of a π-conjugated telluro[3,2-β][1]-tellurophene-based synthon that, embodying pyridyl and haloaryl chalcogen-bonding acceptors, self-assembles into nanoribbons through chalcogen bonds. The ribbons π-stack in a multi-layered architecture both in single crystals and thin films. Theoretical studies of the electronic states of chalcogen-bonded material showed the presence of a local charge density between Te and N atoms. OTFT-based charge transport measurements showed hole-transport properties for this material. Its integration as a p-type semiconductor in multi-layered CuI-based light-emitting electrochemical cells (LECs) led to a 10-fold increase in stability (38 h vs. 3 h) compared to single-layered devices. Finally, using the reference tellurotellurophene congener bearing a C−H group instead of the pyridyl N atom, a herringbone solid-state assembly is formed without charge transport features, resulting in LECs with poor stabilities (<1 h).}, keywords = {}, pubstate = {published}, tppubtype = {article} } This work describes the design and synthesis of a π-conjugated telluro[3,2-β][1]-tellurophene-based synthon that, embodying pyridyl and haloaryl chalcogen-bonding acceptors, self-assembles into nanoribbons through chalcogen bonds. The ribbons π-stack in a multi-layered architecture both in single crystals and thin films. Theoretical studies of the electronic states of chalcogen-bonded material showed the presence of a local charge density between Te and N atoms. OTFT-based charge transport measurements showed hole-transport properties for this material. Its integration as a p-type semiconductor in multi-layered CuI-based light-emitting electrochemical cells (LECs) led to a 10-fold increase in stability (38 h vs. 3 h) compared to single-layered devices. Finally, using the reference tellurotellurophene congener bearing a C−H group instead of the pyridyl N atom, a herringbone solid-state assembly is formed without charge transport features, resulting in LECs with poor stabilities (<1 h). |
Chen, Y; Wang, H; Luo, F; Montes-García, V; Liu, Z; Samorì, P Nanofloating gate modulated synaptic organic light-emitting transistors for reconfigurable displays Journal Article In: Sci. Adv., 8 (eabq4824), 2022. @article{Chen2022, title = {Nanofloating gate modulated synaptic organic light-emitting transistors for reconfigurable displays}, author = {Y. Chen and H. Wang and F. Luo and V. Montes-García and Z. Liu and P. Samorì}, editor = {Science}, url = {https://doi.org/10.1126/sciadv.abq4824}, year = {2022}, date = {2022-09-14}, journal = {Sci. Adv.}, volume = {8}, number = {eabq4824}, abstract = {The use of postsynaptic current to drive long-lasting luminescence holds a disruptive potential for harnessing the next-generation of smart displays. Multiresponsive long afterglow emission can be achieved by integrating light-emitting polymers in electric spiked transistors trigged by distinct presynaptic signals inputs. Here, we report a highly effective electric spiked long afterglow organic light-emitting transistor (LAOLET), whose operation relies on a nanofloating gate architecture. Long afterglow emission with reconfigurable brightness and retention time is observed upon applying specific positive gate voltage spiked. Conversely, when negative gate voltage stimulus is applied, these LAOLETs function as click-on display. Interestingly, upon endowing the device with force sensing capabilities, it can operate as a long afterglow pressure sensor that emits long-lasting green light subsequently to a controlled extrusion action.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The use of postsynaptic current to drive long-lasting luminescence holds a disruptive potential for harnessing the next-generation of smart displays. Multiresponsive long afterglow emission can be achieved by integrating light-emitting polymers in electric spiked transistors trigged by distinct presynaptic signals inputs. Here, we report a highly effective electric spiked long afterglow organic light-emitting transistor (LAOLET), whose operation relies on a nanofloating gate architecture. Long afterglow emission with reconfigurable brightness and retention time is observed upon applying specific positive gate voltage spiked. Conversely, when negative gate voltage stimulus is applied, these LAOLETs function as click-on display. Interestingly, upon endowing the device with force sensing capabilities, it can operate as a long afterglow pressure sensor that emits long-lasting green light subsequently to a controlled extrusion action. |
Urbanos, F J; Gullace, S; Samorì, P MoS2 Defect Healing for High-Performance Chemical Sensing of Polycyclic Aromatic Hydrocarbons Journal Article In: ACS Nano, 16 , pp. 11234–11243, 2022. @article{Urbanos2022, title = {MoS2 Defect Healing for High-Performance Chemical Sensing of Polycyclic Aromatic Hydrocarbons}, author = {F. J. Urbanos and S. Gullace and P. Samorì}, editor = {ACS Publcation}, url = {https://doi.org/10.1021/acsnano.2c04503}, year = {2022}, date = {2022-07-16}, journal = {ACS Nano}, volume = {16}, pages = {11234–11243}, abstract = {The increasing population and industrial development are responsible for environmental pollution. Among toxic chemicals, polycyclic aromatic hydrocarbons (PAHs) are highly carcinogenic contaminants resulting from the incomplete combustion of organic materials. Two-dimensional materials, such as transition metal dichalcogenides (TMDCs), are ideal sensory scaffolds, combining high surface-to-volume ratio with physical and chemical properties that are strongly susceptible to environmental changes. TMDCs can be integrated in field-effect transistors (FETs), which can operate as high-performance chemical detectors of (non)covalent interaction with small molecules. Here, we have developed MoS2-based FETs as platforms for PAHs sensing, relying on the affinity of the planar polyaromatic molecules for the basal plane of MoS2 and the structural defects in its lattice. X-ray photoelectron spectroscopy analysis, photoluminescence measurements, and transfer characteristics showed a notable reduction in the defectiveness of MoS2 and a p-type doping upon exposure to PAHs solutions, with a magnitude determined by the correlation between the ionization energies (EI) of the PAH and that of MoS2. Naphthalene, endowed with the higher EI among the studied PAHs, exhibited the highest output. We observed a log–log correlation between MoS2 doping and naphthalene concentration in water in a wide range (10–9–10–6 M), as well as a reversible response to the analyte. Naphthalene concentrations as low as 0.128 ppb were detected, being below the limits imposed by health regulations for drinking water. Furthermore, our MoS2 devices can reversibly detect vapors of naphthalene with both an electrical and optical readout, confirming that our architecture could operate as a dual sensing platform.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The increasing population and industrial development are responsible for environmental pollution. Among toxic chemicals, polycyclic aromatic hydrocarbons (PAHs) are highly carcinogenic contaminants resulting from the incomplete combustion of organic materials. Two-dimensional materials, such as transition metal dichalcogenides (TMDCs), are ideal sensory scaffolds, combining high surface-to-volume ratio with physical and chemical properties that are strongly susceptible to environmental changes. TMDCs can be integrated in field-effect transistors (FETs), which can operate as high-performance chemical detectors of (non)covalent interaction with small molecules. Here, we have developed MoS2-based FETs as platforms for PAHs sensing, relying on the affinity of the planar polyaromatic molecules for the basal plane of MoS2 and the structural defects in its lattice. X-ray photoelectron spectroscopy analysis, photoluminescence measurements, and transfer characteristics showed a notable reduction in the defectiveness of MoS2 and a p-type doping upon exposure to PAHs solutions, with a magnitude determined by the correlation between the ionization energies (EI) of the PAH and that of MoS2. Naphthalene, endowed with the higher EI among the studied PAHs, exhibited the highest output. We observed a log–log correlation between MoS2 doping and naphthalene concentration in water in a wide range (10–9–10–6 M), as well as a reversible response to the analyte. Naphthalene concentrations as low as 0.128 ppb were detected, being below the limits imposed by health regulations for drinking water. Furthermore, our MoS2 devices can reversibly detect vapors of naphthalene with both an electrical and optical readout, confirming that our architecture could operate as a dual sensing platform. |
Pakulski, D; Montes-García, V; Gorczyński, A; Czepa, W; Chudziak, T; Samorì, P; Ciesielski, A Thiol-decorated covalent organic frameworks as multifunctional materials for high-performance supercapacitors and heterogeneous catalysis Journal Article In: J. Mater. Chem. A, 10 , pp. 16685–16696, 2022. @article{Pakulski2022, title = {Thiol-decorated covalent organic frameworks as multifunctional materials for high-performance supercapacitors and heterogeneous catalysis}, author = {D. Pakulski and V. Montes-García and A. Gorczyński and W. Czepa and T. Chudziak and P. Samorì and A. Ciesielski}, editor = {RSC }, url = {https://doi.org/10.1039/d2ta03867f }, year = {2022}, date = {2022-07-13}, journal = {J. Mater. Chem. A}, volume = {10}, pages = {16685–16696}, abstract = {Tunable physicochemical properties combined with the high chemical and thermal stabilities of covalent organic frameworks (COFs) make them ideal candidates for the next generation of energy storage systems. The integration of redox-active moieties (e.g., thiols) in COFs imparts them a pseudocapacitive characteristic and represents an efficient strategy to boost their performance as electrochemical supercapacitors (SCs). We report the synthesis of two thiol-decorated COFs (SH-COF-1 and SH-COF-2) via the condensation between 2,5-diaminobenzene-1,4-dithiol (DABDT) and benzene-1,3,5-tricarboxaldehyde (TBA), or 1,2,4,5-tetrakis-(4-formylphenyl)benzene (TFPB), respectively. SH-COF-1, which possesses a higher number of thiol groups per structural repeat unit compared to SH-COF-2, exhibits a higher surface area (227 m2 g−1) and enhanced electrochemical performance (areal capacitance of 118 mF cm−2 and a capacitance retention >95% after 1000 cycles), being superior to previously reported COFs missing redox-active units in their scaffolds. Moreover, to demonstrate the multifunctionality resulting from the presence of thiol groups, AuNPs were in situ grown using SH-COFs as templates. By taking advantage of the strength of the bonding between the AuNPs and the SH-COFs, Au-SH-COF hybrids were used as heterogeneous catalysts for the reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP), showing an excellent catalytic activity kobs, of 1.01 min−1 and 0.71 min−1 for Au-SH-COF-1 and Au-SH-COF-2, respectively, and long-term performance (4-NP to 4-AP conversion above 95% after 10 catalytic cycles). This work highlights the importance of COFs' molecular design towards the development of highly efficient (multi)functional materials.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Tunable physicochemical properties combined with the high chemical and thermal stabilities of covalent organic frameworks (COFs) make them ideal candidates for the next generation of energy storage systems. The integration of redox-active moieties (e.g., thiols) in COFs imparts them a pseudocapacitive characteristic and represents an efficient strategy to boost their performance as electrochemical supercapacitors (SCs). We report the synthesis of two thiol-decorated COFs (SH-COF-1 and SH-COF-2) via the condensation between 2,5-diaminobenzene-1,4-dithiol (DABDT) and benzene-1,3,5-tricarboxaldehyde (TBA), or 1,2,4,5-tetrakis-(4-formylphenyl)benzene (TFPB), respectively. SH-COF-1, which possesses a higher number of thiol groups per structural repeat unit compared to SH-COF-2, exhibits a higher surface area (227 m2 g−1) and enhanced electrochemical performance (areal capacitance of 118 mF cm−2 and a capacitance retention >95% after 1000 cycles), being superior to previously reported COFs missing redox-active units in their scaffolds. Moreover, to demonstrate the multifunctionality resulting from the presence of thiol groups, AuNPs were in situ grown using SH-COFs as templates. By taking advantage of the strength of the bonding between the AuNPs and the SH-COFs, Au-SH-COF hybrids were used as heterogeneous catalysts for the reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP), showing an excellent catalytic activity kobs, of 1.01 min−1 and 0.71 min−1 for Au-SH-COF-1 and Au-SH-COF-2, respectively, and long-term performance (4-NP to 4-AP conversion above 95% after 10 catalytic cycles). This work highlights the importance of COFs' molecular design towards the development of highly efficient (multi)functional materials. |
de Oliveira, Furlan R; Montes-García, V; Livio, P A; González-García, M B; Fanjul-Bolado, P; Casalini, S; Samorì, P Selective Ion Sensing in Artificial Sweat Using Low-Cost Reduced Graphene Oxide Liquid-Gated Plastic Transistors Journal Article In: Small, 18 (2201861), 2022. @article{deOliveira2022, title = {Selective Ion Sensing in Artificial Sweat Using Low-Cost Reduced Graphene Oxide Liquid-Gated Plastic Transistors}, author = {R. Furlan de Oliveira and V. Montes-García and P. A. Livio and M. B. González-García and P. Fanjul-Bolado and S. Casalini and P. Samorì}, editor = {Wiley Online Library}, url = { https://doi.org/10.1002/smll.202201861}, year = {2022}, date = {2022-07-08}, journal = {Small}, volume = {18}, number = {2201861}, abstract = {Health monitoring is experiencing a radical shift from clinic-based to point-of-care and wearable technologies, and a variety of nanomaterials and transducers have been employed for this purpose. 2D materials (2DMs) hold enormous potential for novel electronics, yet they struggle to meet the requirements of wearable technologies. Here, aiming to foster the development of 2DM-based wearable technologies, reduced graphene oxide (rGO)-based liquid-gated transistors (LGTs) for cation sensing in artificial sweat endowed with distinguished performance and great potential for scalable manufacturing is reported. Laser micromachining is employed to produce flexible transistor test patterns employing rGO as the electronic transducer. Analyte selectivity is achieved by functionalizing the transistor channel with ion-selective membranes (ISMs) via a simple casting method. Real-time monitoring of K+ and Na+ in artificial sweat is carried out employing a gate voltage pulsed stimulus to take advantage of the fast responsivity of rGO. The sensors show excellent selectivity toward the target analyte, low working voltages (<0.5 V), fast (5–15 s), linear response at a wide range of concentrations (10 µm to 100 mm), and sensitivities of 1 µA/decade. The reported strategy is an important step forward toward the development of wearable sensors based on 2DMs for future health monitoring technologies.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Health monitoring is experiencing a radical shift from clinic-based to point-of-care and wearable technologies, and a variety of nanomaterials and transducers have been employed for this purpose. 2D materials (2DMs) hold enormous potential for novel electronics, yet they struggle to meet the requirements of wearable technologies. Here, aiming to foster the development of 2DM-based wearable technologies, reduced graphene oxide (rGO)-based liquid-gated transistors (LGTs) for cation sensing in artificial sweat endowed with distinguished performance and great potential for scalable manufacturing is reported. Laser micromachining is employed to produce flexible transistor test patterns employing rGO as the electronic transducer. Analyte selectivity is achieved by functionalizing the transistor channel with ion-selective membranes (ISMs) via a simple casting method. Real-time monitoring of K+ and Na+ in artificial sweat is carried out employing a gate voltage pulsed stimulus to take advantage of the fast responsivity of rGO. The sensors show excellent selectivity toward the target analyte, low working voltages (<0.5 V), fast (5–15 s), linear response at a wide range of concentrations (10 µm to 100 mm), and sensitivities of 1 µA/decade. The reported strategy is an important step forward toward the development of wearable sensors based on 2DMs for future health monitoring technologies. |
Liu, Z; Fu, S; Liu, X; Narita, A; Samorì, P; Bonn, M; Wang, H I Small Size, Big Impact: Recent Progress in Bottom-Up Synthesized Nanographenes for Optoelectronic and Energy Applications Journal Article In: Adv. Sci., 9 (2106055), 2022. @article{Liu2022b, title = {Small Size, Big Impact: Recent Progress in Bottom-Up Synthesized Nanographenes for Optoelectronic and Energy Applications}, author = {Z. Liu and S. Fu and X. Liu and A. Narita and P. Samorì and M. Bonn and H. I. Wang}, editor = {Wiley Online Library}, url = {https://doi.org/10.1002/advs.202106055}, year = {2022}, date = {2022-07-06}, journal = {Adv. Sci.}, volume = {9}, number = {2106055}, abstract = {Bottom-up synthesized graphene nanostructures, including 0D graphene quantum dots and 1D graphene nanoribbons, have recently emerged as promising candidates for efficient, green optoelectronic, and energy storage applications. The versatility in their molecular structures offers a large and novel library of nanographenes with excellent and adjustable optical, electronic, and catalytic properties. In this minireview, recent progress on the fundamental understanding of the properties of different graphene nanostructures, and their state-of-the-art applications in optoelectronics and energy storage are summarized. The properties of pristine nanographenes, including high emissivity and intriguing blinking effect in graphene quantum dots, superior charge transport properties in graphene nanoribbons, and edge-specific electrochemistry in various graphene nanostructures, are highlighted. Furthermore, it is shown that emerging nanographene-2D material-based van der Waals heterostructures provide an exciting opportunity for efficient green optoelectronics with tunable characteristics. Finally, challenges and opportunities of the field are highlighted by offering guidelines for future combined efforts in the synthesis, assembly, spectroscopic, and electrical studies as well as (nano)fabrication to boost the progress toward advanced device applications.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Bottom-up synthesized graphene nanostructures, including 0D graphene quantum dots and 1D graphene nanoribbons, have recently emerged as promising candidates for efficient, green optoelectronic, and energy storage applications. The versatility in their molecular structures offers a large and novel library of nanographenes with excellent and adjustable optical, electronic, and catalytic properties. In this minireview, recent progress on the fundamental understanding of the properties of different graphene nanostructures, and their state-of-the-art applications in optoelectronics and energy storage are summarized. The properties of pristine nanographenes, including high emissivity and intriguing blinking effect in graphene quantum dots, superior charge transport properties in graphene nanoribbons, and edge-specific electrochemistry in various graphene nanostructures, are highlighted. Furthermore, it is shown that emerging nanographene-2D material-based van der Waals heterostructures provide an exciting opportunity for efficient green optoelectronics with tunable characteristics. Finally, challenges and opportunities of the field are highlighted by offering guidelines for future combined efforts in the synthesis, assembly, spectroscopic, and electrical studies as well as (nano)fabrication to boost the progress toward advanced device applications. |
Jouclas, R; Liu, J; Volpi, M; de Moraes, L S; Garbay, G; McIntosh, N; Bardini, M; Lemaur, V; Vercouter, A; Gatsios, C; Modesti, F; Turetta, N; Beljonne, D; Cornil, J; Kennedy, A R; Koch, N; Erk, P; Samorì, P; Schweicher, G; Geerts, Y H Dinaphthotetrathienoacenes: Synthesis, Characterization, and Applications in Organic Field-Effect Transistors Journal Article In: Adv. Sci., 9 (2105674), 2022. @article{Jouclas2022, title = {Dinaphthotetrathienoacenes: Synthesis, Characterization, and Applications in Organic Field-Effect Transistors}, author = {R. Jouclas and J. Liu and M. Volpi and L. S. de Moraes and G. Garbay and N. McIntosh and M. Bardini and V. Lemaur and A. Vercouter and C. Gatsios and F. Modesti and N. Turetta and D. Beljonne and J. Cornil and A. R. Kennedy and N. Koch and P. Erk and P. Samorì and G. Schweicher and Y. H. Geerts}, editor = {Wiley Online Library}, url = {https://doi.org/10.1002/advs.202105674}, year = {2022}, date = {2022-07-06}, journal = {Adv. Sci.}, volume = {9}, number = {2105674}, abstract = {The charge transport of crystalline organic semiconductors is limited by dynamic disorder that tends to localize charges. It is the main hurdle to overcome in order to significantly increase charge carrier mobility. An innovative design that combines a chemical structure based on sulfur-rich thienoacene with a solid-state herringbone (HB) packing is proposed and the synthesis, physicochemical characterization, and charge transport properties of two new thienoacenes bearing a central tetrathienyl core fused with two external naphthyl rings: naphtho[2,3-b]thieno-[2′′′,3′′′:4′′,5′′]thieno[2″,3″:4′,5′]thieno[3′,2′-b]naphtho[2,3-b]thiophene (DN4T) and naphtho[1,2-b]thieno-[2′′′,3′′′:4′′,5′′]thieno[2′′,3′′:4′,5′]thieno[3′,2′-b]naphtho[1,2-b]thiophene are presented. Both compounds crystallize with a HB pattern structure and present transfer integrals ranging from 33 to 99 meV (for the former) within the HB plane of charge transport. Molecular dynamics simulations point toward an efficient resilience of the transfer integrals to the intermolecular sliding motion commonly responsible for strong variations of the electronic coupling in the crystal. Best device performances are reached with DN4T with hole mobility up to μ = 2.1 cm2 V−1s−1 in polycrystalline organic field effect transistors, showing the effectiveness of the electronic coupling enabled by the new aromatic core. These promising results pave the way to the design of high-performing materials based on this new thienoacene, notably through the introduction of alkyl side-chains.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The charge transport of crystalline organic semiconductors is limited by dynamic disorder that tends to localize charges. It is the main hurdle to overcome in order to significantly increase charge carrier mobility. An innovative design that combines a chemical structure based on sulfur-rich thienoacene with a solid-state herringbone (HB) packing is proposed and the synthesis, physicochemical characterization, and charge transport properties of two new thienoacenes bearing a central tetrathienyl core fused with two external naphthyl rings: naphtho[2,3-b]thieno-[2′′′,3′′′:4′′,5′′]thieno[2″,3″:4′,5′]thieno[3′,2′-b]naphtho[2,3-b]thiophene (DN4T) and naphtho[1,2-b]thieno-[2′′′,3′′′:4′′,5′′]thieno[2′′,3′′:4′,5′]thieno[3′,2′-b]naphtho[1,2-b]thiophene are presented. Both compounds crystallize with a HB pattern structure and present transfer integrals ranging from 33 to 99 meV (for the former) within the HB plane of charge transport. Molecular dynamics simulations point toward an efficient resilience of the transfer integrals to the intermolecular sliding motion commonly responsible for strong variations of the electronic coupling in the crystal. Best device performances are reached with DN4T with hole mobility up to μ = 2.1 cm2 V−1s−1 in polycrystalline organic field effect transistors, showing the effectiveness of the electronic coupling enabled by the new aromatic core. These promising results pave the way to the design of high-performing materials based on this new thienoacene, notably through the introduction of alkyl side-chains. |
Peng, H; Zheng, Y; Antheaume, C; Samorì, P; Ciesielski, A Novel thiophene-based donor–acceptor scaffolds as cathodes for rechargeable aqueous zinc-ion hybrid supercapacitors Journal Article In: Chem. Commun., 58 , pp. 6689–6692, 2022. @article{Peng2022, title = {Novel thiophene-based donor–acceptor scaffolds as cathodes for rechargeable aqueous zinc-ion hybrid supercapacitors}, author = {H. Peng and Y. Zheng and C. Antheaume and P. Samorì and A. Ciesielski}, editor = {Royal Society of Chemistry}, url = {https://doi.org/10.1039/d2cc02021a}, year = {2022}, date = {2022-05-13}, journal = {Chem. Commun.}, volume = {58 }, pages = {6689–6692}, abstract = {Well-defined π-conjugated thiophene donor–acceptor molecules play an important role in different fields ranging from synthetic chemistry to materials science. Their chemical structure provides specific electronic and physicochemical properties, which can be further tuned by the introduction of functional groups. Herein, we design and synthesize two novel thiophene-based π-conjugated donor–acceptor molecules TDA-1 and TDA-2 through Aldol and Knoevenagel condensations. In our proof-of-concept study we report for the first time on the use of small organic molecules employed in aqueous zinc-ion hybrid supercapacitors (Zn-HSCs),which exhibit capacitance as high as 206.7 and 235.2 F g−1 for TDA-1, and TDA-2, respectively...}, keywords = {}, pubstate = {published}, tppubtype = {article} } Well-defined π-conjugated thiophene donor–acceptor molecules play an important role in different fields ranging from synthetic chemistry to materials science. Their chemical structure provides specific electronic and physicochemical properties, which can be further tuned by the introduction of functional groups. Herein, we design and synthesize two novel thiophene-based π-conjugated donor–acceptor molecules TDA-1 and TDA-2 through Aldol and Knoevenagel condensations. In our proof-of-concept study we report for the first time on the use of small organic molecules employed in aqueous zinc-ion hybrid supercapacitors (Zn-HSCs),which exhibit capacitance as high as 206.7 and 235.2 F g−1 for TDA-1, and TDA-2, respectively... |
Lin, H; Peng, S; Guo, S; Ma, B; Lucherelli, M A; Royer, C; Ippolito, S; Samorì, P; Bianco, A 2D Materials and Primary Human Dendritic Cells: A Comparative Cytotoxicity Study Journal Article In: Small, 18 (2107652), 2022. @article{Lin2022, title = {2D Materials and Primary Human Dendritic Cells: A Comparative Cytotoxicity Study}, author = {H. Lin and S. Peng and S. Guo and B. Ma and M. A. Lucherelli and C. Royer and S. Ippolito and P. Samorì and A. Bianco}, url = {https://doi.org/10.1002/smll.202107652}, year = {2022}, date = {2022-04-21}, journal = {Small}, volume = {18}, number = {2107652}, abstract = {Human health can be affected by materials indirectly through exposure to the environment or directly through close contact and uptake. With the ever-growing use of 2D materials in many applications such as electronics, medical therapeutics, molecular sensing, and energy storage, it has become more pertinent to investigate their impact on the immune system. Dendritic cells (DCs) are highly important, considering their role as the main link between the innate and the adaptive immune system. By using primary human DCs, it is shown that hexagonal boron nitride (hBN), graphene oxide (GO) and molybdenum disulphide have minimal effects on viability. In particular, it is evidenced that hBN and GO increase DC maturation, while GO leads to the release of reactive oxygen species and pro-inflammatory cytokines. hBN and MoS2 increase T cell proliferation with and without the presence of DCs. hBN in particular does not show any sign of downstream T cell polarization. The study allows ranking of the three materials in terms of inherent toxicity, providing the following trend: GO > hBN ≈ MoS2, with GO the most cytotoxic.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Human health can be affected by materials indirectly through exposure to the environment or directly through close contact and uptake. With the ever-growing use of 2D materials in many applications such as electronics, medical therapeutics, molecular sensing, and energy storage, it has become more pertinent to investigate their impact on the immune system. Dendritic cells (DCs) are highly important, considering their role as the main link between the innate and the adaptive immune system. By using primary human DCs, it is shown that hexagonal boron nitride (hBN), graphene oxide (GO) and molybdenum disulphide have minimal effects on viability. In particular, it is evidenced that hBN and GO increase DC maturation, while GO leads to the release of reactive oxygen species and pro-inflammatory cytokines. hBN and MoS2 increase T cell proliferation with and without the presence of DCs. hBN in particular does not show any sign of downstream T cell polarization. The study allows ranking of the three materials in terms of inherent toxicity, providing the following trend: GO > hBN ≈ MoS2, with GO the most cytotoxic. |
Liu, Z; Hu, Y; Zheng, W; Wang, C; Baaziz, W; Richard, F; Ersen, O; Bonn, M; Wang, H I; Narita, A; Ciesielski, A; Müllen, K; Samorì, P Untying the Bundles of Solution-Synthesized Graphene Nanoribbons for Highly Capacitive Micro-Supercapacitors Journal Article In: Adv. Funct. Mater., 32 (2109543), 2022. @article{Liu2022, title = {Untying the Bundles of Solution-Synthesized Graphene Nanoribbons for Highly Capacitive Micro-Supercapacitors}, author = {Z. Liu and Y. Hu and W. Zheng and C. Wang and W. Baaziz and F. Richard and O. Ersen and M. Bonn and H. I. Wang and A. Narita and A. Ciesielski and K. Müllen and P. Samorì}, url = {https://doi.org/10.1002/adfm.202109543}, year = {2022}, date = {2022-04-19}, journal = {Adv. Funct. Mater.}, volume = {32}, number = {2109543}, abstract = {The precise bottom-up synthesis of graphene nanoribbons (GNRs) with controlled width and edge structures may compensate for graphene's limitations, such as the absence of an electronic bandgap. At the same time, GNRs maintain graphene's unique lattice structure in one dimension and provide more open-edge structures compared to graphene, thus allowing faster ion diffusion, which makes GNRs highly promising for energy storage systems. However, the current solution-synthesized GNRs suffer from severe aggregation due to the strong π–π interactions, which limits their potential applications. Thus, it is indispensable to develop a facile and scalable approach to exfoliate the GNRs from the postsynthetic aggregates, yielding individual nanoribbons. Here, a high-shear-mixing approach is demonstrated to untie the GNR bundles into practically individual GNRs, by introducing suitable molecular interactions. The micro-supercapacitor (MSC) electrode based on solution-processed GNR film exhibits an excellent volumetric capacitance of 355 F cm−3 and a high power density of 550 W cm−3, reaching the state-of-the-art performance of graphene and related carbon materials, and thus demonstrating the great potential of GNRs as electrode materials for future energy storage.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The precise bottom-up synthesis of graphene nanoribbons (GNRs) with controlled width and edge structures may compensate for graphene's limitations, such as the absence of an electronic bandgap. At the same time, GNRs maintain graphene's unique lattice structure in one dimension and provide more open-edge structures compared to graphene, thus allowing faster ion diffusion, which makes GNRs highly promising for energy storage systems. However, the current solution-synthesized GNRs suffer from severe aggregation due to the strong π–π interactions, which limits their potential applications. Thus, it is indispensable to develop a facile and scalable approach to exfoliate the GNRs from the postsynthetic aggregates, yielding individual nanoribbons. Here, a high-shear-mixing approach is demonstrated to untie the GNR bundles into practically individual GNRs, by introducing suitable molecular interactions. The micro-supercapacitor (MSC) electrode based on solution-processed GNR film exhibits an excellent volumetric capacitance of 355 F cm−3 and a high power density of 550 W cm−3, reaching the state-of-the-art performance of graphene and related carbon materials, and thus demonstrating the great potential of GNRs as electrode materials for future energy storage. |
Čonková, M; Montes-García, V; Konopka, M; Ciesielski, A; Samorì, P; Stefankiewicz, A R Schiff base capped gold nanoparticles for transition metal cation sensing in organic media Journal Article In: Chem. Commun., 58 , pp. 5773–5776, 2022. @article{Čonková2022, title = {Schiff base capped gold nanoparticles for transition metal cation sensing in organic media}, author = {M. Čonková and V. Montes-García and M. Konopka and A. Ciesielski and P. Samorì and A. R. Stefankiewicz}, url = {https://doi.org/10.1039/d2cc00497f}, year = {2022}, date = {2022-04-13}, journal = {Chem. Commun.}, volume = {58}, pages = {5773–5776}, abstract = {We report a fast and ultrasensitive colorimetric method for the detection of transition metal ions (Fe3+, Cu2+, Ni2+) in a mixture of toluene–acetonitrile using Schiff base functionalized gold nanoparticles. We achieved limits of detection for the three metal ions at least two orders of magnitude lower than the EU recommended limits. Finally, our methodology was assessed for the determination of nickel in the organic waste of a relevant industrial reaction.}, keywords = {}, pubstate = {published}, tppubtype = {article} } We report a fast and ultrasensitive colorimetric method for the detection of transition metal ions (Fe3+, Cu2+, Ni2+) in a mixture of toluene–acetonitrile using Schiff base functionalized gold nanoparticles. We achieved limits of detection for the three metal ions at least two orders of magnitude lower than the EU recommended limits. Finally, our methodology was assessed for the determination of nickel in the organic waste of a relevant industrial reaction. |
Zhou, J; Zhang, C; Shi, L; Chen, X; Kim, T S; Gyeon, M; Chen, J; Wang, J; Yu, L; Wang, X; Kang, K; Orgiu, E; Samorì, P; Watanabe, K; Taniguchi, T; Tsukagoshi, K; Wang, P; Shi, Y; Li, S Non-invasive digital etching of van der Waals semiconductors Journal Article In: Nat. Commun., 13 (1844), 2022. @article{Zhou2022, title = {Non-invasive digital etching of van der Waals semiconductors}, author = {J. Zhou and C. Zhang and L. Shi and X. Chen and T. S. Kim and M. Gyeon and J. Chen and J. Wang and L. Yu and X. Wang and K. Kang and E. Orgiu and P. Samorì and K. Watanabe and T. Taniguchi and K. Tsukagoshi and P. Wang and Y. Shi and S. Li}, url = {https://doi.org/10.1038/s41467-022-29447-6}, year = {2022}, date = {2022-04-05}, journal = {Nat. Commun.}, volume = {13}, number = {1844}, abstract = {The capability to finely tailor material thickness with simultaneous atomic precision and non-invasivity would be useful for constructing quantum platforms and post-Moore microelectronics. However, it remains challenging to attain synchronized controls over tailoring selectivity and precision. Here we report a protocol that allows for non-invasive and atomically digital etching of van der Waals transition-metal dichalcogenides through selective alloying via low-temperature thermal diffusion and subsequent wet etching. The mechanism of selective alloying between sacrifice metal atoms and defective or pristine dichalcogenides is analyzed with high-resolution scanning transmission electron microscopy. Also, the non-invasive nature and atomic level precision of our etching technique are corroborated by consistent spectral, crystallographic, and electrical characterization measurements. The low-temperature charge mobility of as-etched MoS2 reaches up to 1200 cm2 V−1s−1, comparable to that of exfoliated pristine counterparts. The entire protocol represents a highly precise and non-invasive tailoring route for material manipulation.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The capability to finely tailor material thickness with simultaneous atomic precision and non-invasivity would be useful for constructing quantum platforms and post-Moore microelectronics. However, it remains challenging to attain synchronized controls over tailoring selectivity and precision. Here we report a protocol that allows for non-invasive and atomically digital etching of van der Waals transition-metal dichalcogenides through selective alloying via low-temperature thermal diffusion and subsequent wet etching. The mechanism of selective alloying between sacrifice metal atoms and defective or pristine dichalcogenides is analyzed with high-resolution scanning transmission electron microscopy. Also, the non-invasive nature and atomic level precision of our etching technique are corroborated by consistent spectral, crystallographic, and electrical characterization measurements. The low-temperature charge mobility of as-etched MoS2 reaches up to 1200 cm2 V−1s−1, comparable to that of exfoliated pristine counterparts. The entire protocol represents a highly precise and non-invasive tailoring route for material manipulation. |
Ippolito, S; Samorì, P Defect Engineering Strategies Toward Controlled Functionalization of Solution-Processed Transition Metal Dichalcogenides Journal Article In: Small Sci., 2 (4), pp. 2100122, 2022. @article{Ippolito2022, title = {Defect Engineering Strategies Toward Controlled Functionalization of Solution-Processed Transition Metal Dichalcogenides}, author = {S. Ippolito and P. Samorì}, editor = {Wiley Online Library}, url = {https://doi.org/10.1002/smsc.202100122}, year = {2022}, date = {2022-04-01}, journal = {Small Sci.}, volume = {2}, number = {4}, pages = {2100122}, abstract = {Solution-processed transition metal dichalcogenides (TMDs) are attracting unceasing attention owing to their wide-ranging portfolio of physicochemical properties, making them prime candidates for low-cost and real-life applications in (opto)electronics, (bio)sensing, and energy-related technologies. The performance of TMD-based devices is strictly interconnected with the inherent features and quality of the materials, which should be tuned in view of their ultimate application. In this regard, the device performance is hitherto undermined by the presence of structural defects inherited from both the bulk systems and the exfoliation procedures. To overcome this limitation, a notable research effort has been devoted to the development of molecular strategies taking advantage of the defective nature of solution-processed TMDs, in order to meticulously tailor their physicochemical properties and expand the range of applicability. In this perspective, some of the most enlightening advances regarding the functionalization approaches exploiting TMD structural defects are presented, introducing the typical “imperfections” encountered in 2D crystal lattices (with different dimensionality, ranging from 0D to 2D) as well as discussing their in situ/ex situ generation methods. Finally, we highlight the future directions, challenges, and opportunities of defect engineering in TMDs by offering guidelines to boost the progress of 2D materials science and related technology.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Solution-processed transition metal dichalcogenides (TMDs) are attracting unceasing attention owing to their wide-ranging portfolio of physicochemical properties, making them prime candidates for low-cost and real-life applications in (opto)electronics, (bio)sensing, and energy-related technologies. The performance of TMD-based devices is strictly interconnected with the inherent features and quality of the materials, which should be tuned in view of their ultimate application. In this regard, the device performance is hitherto undermined by the presence of structural defects inherited from both the bulk systems and the exfoliation procedures. To overcome this limitation, a notable research effort has been devoted to the development of molecular strategies taking advantage of the defective nature of solution-processed TMDs, in order to meticulously tailor their physicochemical properties and expand the range of applicability. In this perspective, some of the most enlightening advances regarding the functionalization approaches exploiting TMD structural defects are presented, introducing the typical “imperfections” encountered in 2D crystal lattices (with different dimensionality, ranging from 0D to 2D) as well as discussing their in situ/ex situ generation methods. Finally, we highlight the future directions, challenges, and opportunities of defect engineering in TMDs by offering guidelines to boost the progress of 2D materials science and related technology. |
Han, B; Zhao, Y; Ma, C; Wang, C; Tian, X; Wang, Y; Hu, W; Samorì, P In: Adv. Mater., 34 (2109445), 2022. @article{Han2022, title = {Asymmetric Chemical Functionalization of Top-Contact Electrodes: Tuning the Charge Injection for High-Performance MoS2 Field-Effect Transistors and Schottky Diodes}, author = {B. Han and Y. Zhao and C. Ma and C. Wang and X. Tian and Y. Wang and W. Hu and P. Samorì}, editor = {Wiley}, url = {https://doi.org/10.1002/adma.202109445}, year = {2022}, date = {2022-03-24}, journal = {Adv. Mater.}, volume = {34}, number = {2109445}, abstract = {The fabrication of high-performance (opto-)electronic devices based on 2D channel materials requires the optimization of the charge injection at electrode–semiconductor interfaces. While chemical functionalization with chemisorbed self-assembled monolayers has been extensively exploited to adjust the work function of metallic electrodes in bottom-contact devices, such a strategy has not been demonstrated for the top-contact configuration, despite the latter being known to offer enhanced charge-injection characteristics. Here, a novel contact engineering method is developed to functionalize gold electrodes in top-contact field-effect transistors (FETs) via the transfer of chemically pre-modified electrodes. The source and drain Au electrodes of the molybdenum disulfide (MoS2) FETs are functionalized with thiolated molecules possessing different dipole moments. While the modification of the electrodes with electron-donating molecules yields a marked improvement of device performance, the asymmetric functionalization of the source and drain electrodes with different molecules with opposed dipole moment enables the fabrication of a high-performance Schottky diode with a rectification ratio of ≈103. This unprecedented strategy to tune the charge injection in top-contact MoS2 FETs is of general applicability for the fabrication of high-performance (opto-)electronic devices, in which asymmetric charge injection is required, enabling tailoring of the device characteristics on demand.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The fabrication of high-performance (opto-)electronic devices based on 2D channel materials requires the optimization of the charge injection at electrode–semiconductor interfaces. While chemical functionalization with chemisorbed self-assembled monolayers has been extensively exploited to adjust the work function of metallic electrodes in bottom-contact devices, such a strategy has not been demonstrated for the top-contact configuration, despite the latter being known to offer enhanced charge-injection characteristics. Here, a novel contact engineering method is developed to functionalize gold electrodes in top-contact field-effect transistors (FETs) via the transfer of chemically pre-modified electrodes. The source and drain Au electrodes of the molybdenum disulfide (MoS2) FETs are functionalized with thiolated molecules possessing different dipole moments. While the modification of the electrodes with electron-donating molecules yields a marked improvement of device performance, the asymmetric functionalization of the source and drain electrodes with different molecules with opposed dipole moment enables the fabrication of a high-performance Schottky diode with a rectification ratio of ≈103. This unprecedented strategy to tune the charge injection in top-contact MoS2 FETs is of general applicability for the fabrication of high-performance (opto-)electronic devices, in which asymmetric charge injection is required, enabling tailoring of the device characteristics on demand. |
Yao, Y; Chen, Y; Wang, K; Turetta, N; Vitale, S; Han, B; Wang, H; Zhang, L; Samorì, P A robust vertical nanoscaffold for recyclable, paintable, and flexible light-emitting devices Journal Article In: Sci. Adv., 8 (eabn2225), 2022. @article{Yao2022, title = {A robust vertical nanoscaffold for recyclable, paintable, and flexible light-emitting devices}, author = {Y. Yao and Y. Chen and K. Wang and N. Turetta and S. Vitale and B. Han and H. Wang and L. Zhang and P. Samorì}, editor = {Science}, url = {https://doi.org/10.1126/sciadv.abn2225}, year = {2022}, date = {2022-03-11}, journal = {Sci. Adv.}, volume = {8}, number = {eabn2225}, abstract = {Organic light-emitting devices are key components for emerging opto- and nanoelectronics applications including health monitoring and smart displays. Here, we report a foldable inverted polymer light-emitting diode (iPLED) based on a self-suspended asymmetrical vertical nanoscaffold replacing the conventional sandwich-like structured LEDs. Our empty vertical-yet-open nanoscaffold exhibits excellent mechanical robustness, proven by unaltered leakage current when applying 1000 cycles of 40-kilopascal pressure loading/unloading, sonication, and folding, with the corresponding iPLEDs displaying a brightness as high as 2300 candela per square meter. By using photolithography and brush painting, arbitrary emitting patterns can be generated via a noninvasive and mask-free process with individual pixel resolution of 10 μm. Our vertical nanoscaffold iPLED can be supported on flexible polyimide foils and be recycled multiple times by washing and refilling with a different conjugated polymer capable of emitting light of different color. This technology combines the traits required for the next generation of high-resolution flexible displays and multifunctional optoelectronics.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Organic light-emitting devices are key components for emerging opto- and nanoelectronics applications including health monitoring and smart displays. Here, we report a foldable inverted polymer light-emitting diode (iPLED) based on a self-suspended asymmetrical vertical nanoscaffold replacing the conventional sandwich-like structured LEDs. Our empty vertical-yet-open nanoscaffold exhibits excellent mechanical robustness, proven by unaltered leakage current when applying 1000 cycles of 40-kilopascal pressure loading/unloading, sonication, and folding, with the corresponding iPLEDs displaying a brightness as high as 2300 candela per square meter. By using photolithography and brush painting, arbitrary emitting patterns can be generated via a noninvasive and mask-free process with individual pixel resolution of 10 μm. Our vertical nanoscaffold iPLED can be supported on flexible polyimide foils and be recycled multiple times by washing and refilling with a different conjugated polymer capable of emitting light of different color. This technology combines the traits required for the next generation of high-resolution flexible displays and multifunctional optoelectronics. |
Chen, Y; Yao, Y; Turetta, N; Samorì, P Vertical organic transistors with short channels for multifunctional optoelectronic devices Journal Article In: J. Mater. Chem. C, , 10 , pp. 2494–2506, 2022. @article{Chen2021b, title = {Vertical organic transistors with short channels for multifunctional optoelectronic devices}, author = {Y. Chen and Y. Yao and N. Turetta and P. Samorì}, editor = {Royal Society of Chemistry}, url = {https://doi.org/10.1039/d1tc05055a}, year = {2022}, date = {2022-02-21}, journal = {J. Mater. Chem. C, }, volume = {10}, pages = {2494–2506}, abstract = {Organic semiconductors are functional (macro)molecules with tunable physical properties that can be processed as mechanically flexible films over large areas via printing and other solution-based casting methods. Their unique characteristics make them ideal active components for the fabrication of novel flexible, low-power, ultra-light and high-performance devices such as displays, memories and sensors. Compared with planar field-effect transistors, vertical transistors emerged as a cheap and up-scalable solution for the fabrication of devices with nanoscale-sized active channels. The latter offers access to higher current densities at low operating voltages and thus to transition frequencies higher than planar organic transistors. As a result, the vertical organic transistor (VOT) design represents an ideal platform for applications requiring fast operating speeds with reduced power consumption, such as phototransistors and light-emitting devices. In fact, the future development of inexpensive and wearable smart devices depends on the ability to fabricate devices that can operate at low voltages as fast switching units while keeping size and manufacturing costs as low as possible. In this Perspective, we examine the most enlightening works on the development of multifunctional VOTs reported during the last decade and we discuss the challenges and opportunities to expand these strategies towards the technological implementation of VOTs in the next generation of opto-electronics and photonics technologies.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Organic semiconductors are functional (macro)molecules with tunable physical properties that can be processed as mechanically flexible films over large areas via printing and other solution-based casting methods. Their unique characteristics make them ideal active components for the fabrication of novel flexible, low-power, ultra-light and high-performance devices such as displays, memories and sensors. Compared with planar field-effect transistors, vertical transistors emerged as a cheap and up-scalable solution for the fabrication of devices with nanoscale-sized active channels. The latter offers access to higher current densities at low operating voltages and thus to transition frequencies higher than planar organic transistors. As a result, the vertical organic transistor (VOT) design represents an ideal platform for applications requiring fast operating speeds with reduced power consumption, such as phototransistors and light-emitting devices. In fact, the future development of inexpensive and wearable smart devices depends on the ability to fabricate devices that can operate at low voltages as fast switching units while keeping size and manufacturing costs as low as possible. In this Perspective, we examine the most enlightening works on the development of multifunctional VOTs reported during the last decade and we discuss the challenges and opportunities to expand these strategies towards the technological implementation of VOTs in the next generation of opto-electronics and photonics technologies. |
Ricciardulli, A G; Wang, Y; Yang, S; Samorì, P Two-Dimensional Violet Phosphorus: A p-Type Semiconductor for (Opto)electronics Journal Article In: J. Am. Chem. Soc., 144 , pp. 3660–3666, 2022. @article{Ricciardulli2022, title = {Two-Dimensional Violet Phosphorus: A p-Type Semiconductor for (Opto)electronics}, author = {A. G. Ricciardulli and Y. Wang and S. Yang and P. Samorì}, editor = {ACS}, url = {https://doi.org/10.1021/jacs.1c12931}, year = {2022}, date = {2022-02-18}, journal = {J. Am. Chem. Soc.}, volume = {144}, pages = {3660–3666}, abstract = {The synthesis of novel two-dimensional (2D) materials displaying an unprecedented composition and structure via the exfoliation of layered systems provides access to uncharted properties. For application in optoelectronics, a vast majority of exfoliated 2D semiconductors possess n-type or more seldom ambipolar characteristics. The shortage of p-type 2D semiconductors enormously hinders the extensive engineering of 2D devices for complementary metal oxide semiconductors (CMOSs) and beyond CMOS applications. However, despite the recent progress in the development of 2D materials endowed with p-type behaviors by direct synthesis or p-doping strategies, finding new structures is still of primary importance. Here, we report the sonication-assisted liquid-phase exfoliation of violet phosphorus (VP) crystals into few-layer-thick flakes and the first exploration of their electrical and optical properties. Field-effect transistors based on exfoliated VP thin films exhibit a p-type transport feature with an Ion/Ioff ratio of 104 and a hole mobility of 2.25 cm2 V–1 s–1 at room temperature. In addition, the VP film-based photodetectors display a photoresponsivity (R) of 10 mA W–1 and a response time down to 0.16 s. Finally, VP embedded into CMOS inverter arrays displays a voltage gain of ∼17. This scalable production method and high quality of the exfoliated material combined with the excellent optoelectronic performances make VP an enticing and versatile p-type candidate for next-generation more-than-Moore (opto)electronics.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The synthesis of novel two-dimensional (2D) materials displaying an unprecedented composition and structure via the exfoliation of layered systems provides access to uncharted properties. For application in optoelectronics, a vast majority of exfoliated 2D semiconductors possess n-type or more seldom ambipolar characteristics. The shortage of p-type 2D semiconductors enormously hinders the extensive engineering of 2D devices for complementary metal oxide semiconductors (CMOSs) and beyond CMOS applications. However, despite the recent progress in the development of 2D materials endowed with p-type behaviors by direct synthesis or p-doping strategies, finding new structures is still of primary importance. Here, we report the sonication-assisted liquid-phase exfoliation of violet phosphorus (VP) crystals into few-layer-thick flakes and the first exploration of their electrical and optical properties. Field-effect transistors based on exfoliated VP thin films exhibit a p-type transport feature with an Ion/Ioff ratio of 104 and a hole mobility of 2.25 cm2 V–1 s–1 at room temperature. In addition, the VP film-based photodetectors display a photoresponsivity (R) of 10 mA W–1 and a response time down to 0.16 s. Finally, VP embedded into CMOS inverter arrays displays a voltage gain of ∼17. This scalable production method and high quality of the exfoliated material combined with the excellent optoelectronic performances make VP an enticing and versatile p-type candidate for next-generation more-than-Moore (opto)electronics. |
Yu, X; Fu, S; Mandal, M; Yao, X; Liu, Z; Zheng, W; Samorì, P; Narita, A; Müllen, K; Andrienko, D; Bonn, M; Wang, H I Tuning interfacial charge transfer in atomically precise nanographene–graphene heterostructures by engineering van der Waals interactions Journal Article In: J. Chem. Phys., 156 (074702), 2022. @article{Yu2022, title = {Tuning interfacial charge transfer in atomically precise nanographene–graphene heterostructures by engineering van der Waals interactions}, author = {X. Yu and S. Fu and M. Mandal and X. Yao and Z. Liu and W. Zheng and P. Samorì and A. Narita and K. Müllen and D. Andrienko and M. Bonn and H. I. Wang}, editor = {API}, url = {https://doi.org/10.1063/5.0081074}, year = {2022}, date = {2022-02-15}, journal = {J. Chem. Phys.}, volume = {156}, number = {074702}, abstract = {Combining strong light absorption and outstanding electrical conductivity, hybrid nanographene–graphene (NG–Gr) van der Waals heterostructures (vdWHs) represent an emerging material platform for versatile optoelectronic devices. Interfacial charge transfer (CT), a fundamental process whose full control remains limited, plays a paramount role in determining the final device performance. Here, we demonstrate that the interlayer vdW interactions can be engineered by tuning the sizes of bottom-up synthesized NGs to control the interfacial electronic coupling strength and, thus, the CT process in NG–Gr vdWHs. By increasing the dimensions of NGs from 42 to 96 sp2 carbon atoms in the polyaromatic core to enhance the interfacial coupling strength, we find that the CT efficiency and rate in NG–Gr vdWHs display a drastic increase of one order of magnitude, despite the fact that the interfacial energy driving the CT process is unfavorably reduced. Our results shed light on the CT mechanism and provide an effective knob to tune the electronic coupling at NG–Gr interfaces by controlling the size-dependent vdW interactions. }, keywords = {}, pubstate = {published}, tppubtype = {article} } Combining strong light absorption and outstanding electrical conductivity, hybrid nanographene–graphene (NG–Gr) van der Waals heterostructures (vdWHs) represent an emerging material platform for versatile optoelectronic devices. Interfacial charge transfer (CT), a fundamental process whose full control remains limited, plays a paramount role in determining the final device performance. Here, we demonstrate that the interlayer vdW interactions can be engineered by tuning the sizes of bottom-up synthesized NGs to control the interfacial electronic coupling strength and, thus, the CT process in NG–Gr vdWHs. By increasing the dimensions of NGs from 42 to 96 sp2 carbon atoms in the polyaromatic core to enhance the interfacial coupling strength, we find that the CT efficiency and rate in NG–Gr vdWHs display a drastic increase of one order of magnitude, despite the fact that the interfacial energy driving the CT process is unfavorably reduced. Our results shed light on the CT mechanism and provide an effective knob to tune the electronic coupling at NG–Gr interfaces by controlling the size-dependent vdW interactions. |
Turetta, N; Stoeckel, M -A; de Oliveira, Furlan R; Devaux, F; Greco, A; Cendra, C; Gullace, S; Gicevičius, M; Chattopadhyay, B; Liu, J; Schweicher, G; Sirringhaus, H; Salleo, A; Bonn, M; Backus, E H G; Geerts, Y H; Samorì, P In: J. Am. Chem. Soc., 144 , pp. 2546–2555, 2022. @article{Turetta2022, title = {High-Performance Humidity Sensing in π-Conjugated Molecular Assemblies through the Engineering of Electron/Proton Transport and Device Interfaces}, author = {N. Turetta and M.-A. Stoeckel and R. Furlan de Oliveira and F. Devaux and A. Greco and C. Cendra and S. Gullace and M. Gicevičius and B. Chattopadhyay and J. Liu and G. Schweicher and H. Sirringhaus and A. Salleo and M. Bonn and E. H. G. Backus and Y. H. Geerts and P. Samorì}, editor = {ACS Publcation}, url = {https://doi.org/10.1021/jacs.1c10119}, year = {2022}, date = {2022-02-07}, journal = {J. Am. Chem. Soc.}, volume = {144}, pages = {2546–2555}, abstract = {The development of systems capable of responding to environmental changes, such as humidity, requires the design and assembly of highly sensitive and efficiently transducing elements. Such a challenge can be mastered only by disentangling the role played by each component of the responsive system, thus ultimately achieving high performance by optimizing the synergistic contribution of all functional elements. Here, we designed and synthesized a novel [1]benzothieno[3,2-b][1]benzothiophene derivative equipped with hydrophilic oligoethylene glycol lateral chains (OEG-BTBT) that can electrically transduce subtle changes in ambient humidity with high current ratios (>104) at low voltages (2 V), reaching state-of-the-art performance. Multiscale structural, spectroscopical, and electrical characterizations were employed to elucidate the role of each device constituent, viz., the active material’s BTBT core and OEG side chains, and the device interfaces. While the BTBT molecular core promotes the self-assembly of (semi)conducting crystalline films, its OEG side chains are prone to adsorb ambient moisture. These chains act as hotspots for hydrogen bonding with atmospheric water molecules that locally dissociate when a bias voltage is applied, resulting in a mixed electronic/protonic long-range conduction throughout the film. Due to the OEG-BTBT molecules’ orientation with respect to the surface and structural defects within the film, water molecules can access the humidity-sensitive sites of the SiO2 substrate surface, whose hydrophilicity can be tuned for an improved device response. The synergistic chemical engineering of materials and interfaces is thus key for designing highly sensitive humidity-responsive electrical devices whose mechanism relies on the interplay of electron and proton transport.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The development of systems capable of responding to environmental changes, such as humidity, requires the design and assembly of highly sensitive and efficiently transducing elements. Such a challenge can be mastered only by disentangling the role played by each component of the responsive system, thus ultimately achieving high performance by optimizing the synergistic contribution of all functional elements. Here, we designed and synthesized a novel [1]benzothieno[3,2-b][1]benzothiophene derivative equipped with hydrophilic oligoethylene glycol lateral chains (OEG-BTBT) that can electrically transduce subtle changes in ambient humidity with high current ratios (>104) at low voltages (2 V), reaching state-of-the-art performance. Multiscale structural, spectroscopical, and electrical characterizations were employed to elucidate the role of each device constituent, viz., the active material’s BTBT core and OEG side chains, and the device interfaces. While the BTBT molecular core promotes the self-assembly of (semi)conducting crystalline films, its OEG side chains are prone to adsorb ambient moisture. These chains act as hotspots for hydrogen bonding with atmospheric water molecules that locally dissociate when a bias voltage is applied, resulting in a mixed electronic/protonic long-range conduction throughout the film. Due to the OEG-BTBT molecules’ orientation with respect to the surface and structural defects within the film, water molecules can access the humidity-sensitive sites of the SiO2 substrate surface, whose hydrophilicity can be tuned for an improved device response. The synergistic chemical engineering of materials and interfaces is thus key for designing highly sensitive humidity-responsive electrical devices whose mechanism relies on the interplay of electron and proton transport. |
Wang, Can; de Oliveira, Rafael Furlan; Jiang, Kaiyue; Zhao, Yuda; Turetta, Nicholas; Ma, Chun; Han, Bin; Zhang, Haiming; Tranca, Diana; Zhuang, Xiaodong; Chi, Lifeng; Ciesielski, Artur; Samorì, Paolo Boosting the electronic and catalytic properties of 2D semiconductors with supramolecular 2D hydrogen-bonded superlattices Journal Article In: Nature communications, 13 (510), 2022. @article{Wang2022, title = {Boosting the electronic and catalytic properties of 2D semiconductors with supramolecular 2D hydrogen-bonded superlattices}, author = { Can Wang and Rafael Furlan de Oliveira and Kaiyue Jiang and Yuda Zhao and Nicholas Turetta and Chun Ma and Bin Han and Haiming Zhang and Diana Tranca and Xiaodong Zhuang and Lifeng Chi and Artur Ciesielski and Paolo Samorì }, editor = {Nature communication}, url = {https://www.nature.com/articles/s41467-022-28116-y}, year = {2022}, date = {2022-01-26}, journal = {Nature communications}, volume = {13}, number = {510}, abstract = {The electronic properties of two-dimensional semiconductors can be strongly modulated by interfacing them with atomically precise self-assembled molecular lattices, yielding hybrid van der Waals heterostructures (vdWHs). While proof-of-concepts exploited molecular assemblies held together by lateral unspecific van der Waals interactions, the use of 2D supramolecular networks relying on specific non-covalent forces is still unexplored. Herein, prototypical hydrogen-bonded 2D networks of cyanuric acid (CA) and melamine (M) are self-assembled onto MoS2 and WSe2 forming hybrid organic/inorganic vdWHs. The charge carrier density of monolayer MoS2 exhibits an exponential increase with the decreasing area occupied by the CA·M unit cell, in a cooperatively amplified process, reaching 2.7 × 1013 cm−2 and thereby demonstrating strong n-doping. When the 2D CA·M network is used as buffer layer, a stark enhancement in the catalytic activity of monolayer MoS2 for hydrogen evolution reactions is observed, outperforming the platinum (Pt) catalyst via gate modulation.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The electronic properties of two-dimensional semiconductors can be strongly modulated by interfacing them with atomically precise self-assembled molecular lattices, yielding hybrid van der Waals heterostructures (vdWHs). While proof-of-concepts exploited molecular assemblies held together by lateral unspecific van der Waals interactions, the use of 2D supramolecular networks relying on specific non-covalent forces is still unexplored. Herein, prototypical hydrogen-bonded 2D networks of cyanuric acid (CA) and melamine (M) are self-assembled onto MoS2 and WSe2 forming hybrid organic/inorganic vdWHs. The charge carrier density of monolayer MoS2 exhibits an exponential increase with the decreasing area occupied by the CA·M unit cell, in a cooperatively amplified process, reaching 2.7 × 1013 cm−2 and thereby demonstrating strong n-doping. When the 2D CA·M network is used as buffer layer, a stark enhancement in the catalytic activity of monolayer MoS2 for hydrogen evolution reactions is observed, outperforming the platinum (Pt) catalyst via gate modulation. |
Zhao, Y; Gobbi, M; Hueso, L E; Samorì, P Molecular Approach to Engineer Two-Dimensional Devices for CMOS and beyond-CMOS Applications Journal Article In: Chem. Rev., 122 , pp. 50-131, 2022. @article{Zhao2022, title = {Molecular Approach to Engineer Two-Dimensional Devices for CMOS and beyond-CMOS Applications}, author = {Y. Zhao and M. Gobbi and L. E. Hueso and P. Samorì}, editor = {ACS Publcation}, url = {https://doi.org/10.1021/acs.chemrev.1c00497}, year = {2022}, date = {2022-01-12}, journal = {Chem. Rev.}, volume = {122}, pages = {50-131}, abstract = {Two-dimensional materials (2DMs) have attracted tremendous research interest over the last two decades. Their unique optical, electronic, thermal, and mechanical properties make 2DMs key building blocks for the fabrication of novel complementary metal–oxide–semiconductor (CMOS) and beyond-CMOS devices. Major advances in device functionality and performance have been made by the covalent or noncovalent functionalization of 2DMs with molecules: while the molecular coating of metal electrodes and dielectrics allows for more efficient charge injection and transport through the 2DMs, the combination of dynamic molecular systems, capable to respond to external stimuli, with 2DMs makes it possible to generate hybrid systems possessing new properties by realizing stimuli-responsive functional devices and thereby enabling functional diversification in More–than–Moore technologies. In this review, we first introduce emerging 2DMs, various classes of (macro)molecules, and molecular switches and discuss their relevant properties. We then turn to 2DM/molecule hybrid systems and the various physical and chemical strategies used to synthesize them. Next, we discuss the use of molecules and assemblies thereof to boost the performance of 2D transistors for CMOS applications and to impart diverse functionalities in beyond–CMOS devices. Finally, we present the challenges, opportunities, and long-term perspectives in this technologically promising field.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Two-dimensional materials (2DMs) have attracted tremendous research interest over the last two decades. Their unique optical, electronic, thermal, and mechanical properties make 2DMs key building blocks for the fabrication of novel complementary metal–oxide–semiconductor (CMOS) and beyond-CMOS devices. Major advances in device functionality and performance have been made by the covalent or noncovalent functionalization of 2DMs with molecules: while the molecular coating of metal electrodes and dielectrics allows for more efficient charge injection and transport through the 2DMs, the combination of dynamic molecular systems, capable to respond to external stimuli, with 2DMs makes it possible to generate hybrid systems possessing new properties by realizing stimuli-responsive functional devices and thereby enabling functional diversification in More–than–Moore technologies. In this review, we first introduce emerging 2DMs, various classes of (macro)molecules, and molecular switches and discuss their relevant properties. We then turn to 2DM/molecule hybrid systems and the various physical and chemical strategies used to synthesize them. Next, we discuss the use of molecules and assemblies thereof to boost the performance of 2D transistors for CMOS applications and to impart diverse functionalities in beyond–CMOS devices. Finally, we present the challenges, opportunities, and long-term perspectives in this technologically promising field. |
Montes-García, V; Samorì, P Janus 2D materials via asymmetric molecular functionalization Journal Article In: Chem. Sci., 13 , pp. 315–328, 2022. @article{Montes-García2022, title = {Janus 2D materials via asymmetric molecular functionalization}, author = {V. Montes-García and P. Samorì}, editor = {Royal Society of Chemistry}, url = {https://doi.org/10.1039/d1sc05836c}, year = {2022}, date = {2022-01-01}, journal = {Chem. Sci.}, volume = {13}, pages = {315–328}, abstract = {Janus two-dimensional materials (2DMs) are a novel class of 2DMs in which the two faces of the material are either asymmetrically functionalized or are exposed to a different local environment. The diversity of the properties imparted to the two opposing sides enables the design of new multifunctional materials for applications in a broad variety of fields including opto-electronics, energy storage, and catalysis. In this perspective, we summarize the most enlightening experimental methods for the asymmetric chemical functionalization of 2DMs with tailored made (macro)molecules by means of a supratopic binding (one side) or antaratopic binding (two sides) process. We describe the emergence of unique electrical and optical characteristics resulting from the asymmetric dressing of the two surfaces. Representative examples of Janus 2DMs towards bandgap engineering, enhanced photoresponse and photoluminescence are provided. In addition, examples of Janus 2DMs for real applications such as energy storage (batteries and supercapacitors) and generation (photovoltaics), opto-electronics (field-effect transistors and photodetectors), catalysis, drug delivery, self-healing materials, chemical sensors and selective capture and separation of small molecules are also described. Finally, we discuss the future directions, challenges, and opportunities to expand the frontiers of Janus 2DMs towards technologies with potential impact in environmental science and biomedical applications.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Janus two-dimensional materials (2DMs) are a novel class of 2DMs in which the two faces of the material are either asymmetrically functionalized or are exposed to a different local environment. The diversity of the properties imparted to the two opposing sides enables the design of new multifunctional materials for applications in a broad variety of fields including opto-electronics, energy storage, and catalysis. In this perspective, we summarize the most enlightening experimental methods for the asymmetric chemical functionalization of 2DMs with tailored made (macro)molecules by means of a supratopic binding (one side) or antaratopic binding (two sides) process. We describe the emergence of unique electrical and optical characteristics resulting from the asymmetric dressing of the two surfaces. Representative examples of Janus 2DMs towards bandgap engineering, enhanced photoresponse and photoluminescence are provided. In addition, examples of Janus 2DMs for real applications such as energy storage (batteries and supercapacitors) and generation (photovoltaics), opto-electronics (field-effect transistors and photodetectors), catalysis, drug delivery, self-healing materials, chemical sensors and selective capture and separation of small molecules are also described. Finally, we discuss the future directions, challenges, and opportunities to expand the frontiers of Janus 2DMs towards technologies with potential impact in environmental science and biomedical applications. |
Martin, C; Jonckheere, D; Coutino-Gonzalez, E; Smolders, S; Bueken, B; Marquez, C; Krajnc, A; Willhammar, T; Kennes, K; Fenwick, O; Richard, F; Samorì, P; Mali, G; Hofkens, J; Roeffaers, M B J; Vos, De D E Metal–biomolecule frameworks (BioMOFs): a novel approach for “green” optoelectronic applications Journal Article In: Chem. Commun., 58 , pp. 677–680, 2022. @article{Martin2022, title = {Metal–biomolecule frameworks (BioMOFs): a novel approach for “green” optoelectronic applications}, author = {C. Martin and D. Jonckheere and E. Coutino-Gonzalez and S. Smolders and B. Bueken and C. Marquez and A. Krajnc and T. Willhammar and K. Kennes and O. Fenwick and F. Richard and P. Samorì and G. Mali and J. Hofkens and M. B. J. Roeffaers and D. E. De Vos}, editor = {Royal Society of Chemistry}, url = {https://doi.org/10.1039/d1cc05214d}, year = {2022}, date = {2022-01-01}, journal = {Chem. Commun.}, volume = {58}, pages = {677–680}, abstract = {In this study, a water-stable microcrystalline bioMOF was synthesized, characterized, and loaded with silver ions or highly emissive rare earth (RE) metals such as Eu3+/Tb3+. The obtained materials were used as active layers in a proof-of-concept sustainable light-emitting device, highlighting the potential of bioMOFs in optoelectronic applications.}, keywords = {}, pubstate = {published}, tppubtype = {article} } In this study, a water-stable microcrystalline bioMOF was synthesized, characterized, and loaded with silver ions or highly emissive rare earth (RE) metals such as Eu3+/Tb3+. The obtained materials were used as active layers in a proof-of-concept sustainable light-emitting device, highlighting the potential of bioMOFs in optoelectronic applications. |
2021 |
Peng, H; Huang, S; Tranca, D; Richard, F; Baaziz, W; Zhuang, X; Samorì, P; Ciesielski, A In: ACS Nano, 15 , pp. 18580–18589, 2021. @article{Peng2021, title = {Quantum Capacitance through Molecular Infiltration of 7,7,8,8-Tetracyanoquinodimethane in Metal–Organic Framework/Covalent Organic Framework Hybrids}, author = {H. Peng and S. Huang and D. Tranca and F. Richard and W. Baaziz and X. Zhuang and P. Samorì and A. Ciesielski}, editor = {ACS Publcation}, url = {https://doi.org/10.1021/acsnano.1c09146}, year = {2021}, date = {2021-11-15}, journal = {ACS Nano}, volume = {15}, pages = {18580–18589}, abstract = {Metal–organic frameworks (MOFs) and covalent organic frameworks (COFs) have been extensively investigated during the last two decades. More recently, a family of hybrid materials (i.e., MOF@COF) has emerged as particularly appealing for gas separation and storage, catalysis, sensing, and drug delivery. MOF@COF hybrids combine the unique characteristics of both MOF and COF components and exhibit peculiar properties including high porosity and large surface area. In this work, we show that the infiltration of redox-active 7,7,8,8-tetracyanoquinodimethane (TCNQ) molecules into the pores of MOF@COF greatly improves the characteristics of the latter, thereby attaining high-performance energy storage devices. Density functional theory (DFT) calculations were employed to guide the design of a MOF@COF-TCNQ hybrid with the TCNQ functional units incorporated in the pores of MOF@COF. To demonstrate potential application of our hybrids, the as-synthesized MOF@COF-TCNQ hybrid has been employed as an active material in supercapacitors. Electrochemical energy storage analysis revealed outstanding supercapacitor performance, as evidenced by a specific areal capacitance of 78.36 mF cm–2 and a high stack volumetric energy density of 4.46 F cm–3, with a capacitance retention of 86.4% after 2000 cycles completed at 0.2 A cm–2. DFT calculation results strongly indicate that the high capacitance of MOF@COF-TCNQ has a quantum capacitance origin. Our liquid-phase infiltration protocol of MOF@COF hybrids with redox-active molecules represents a efficacious approach to design functional porous hybrids.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Metal–organic frameworks (MOFs) and covalent organic frameworks (COFs) have been extensively investigated during the last two decades. More recently, a family of hybrid materials (i.e., MOF@COF) has emerged as particularly appealing for gas separation and storage, catalysis, sensing, and drug delivery. MOF@COF hybrids combine the unique characteristics of both MOF and COF components and exhibit peculiar properties including high porosity and large surface area. In this work, we show that the infiltration of redox-active 7,7,8,8-tetracyanoquinodimethane (TCNQ) molecules into the pores of MOF@COF greatly improves the characteristics of the latter, thereby attaining high-performance energy storage devices. Density functional theory (DFT) calculations were employed to guide the design of a MOF@COF-TCNQ hybrid with the TCNQ functional units incorporated in the pores of MOF@COF. To demonstrate potential application of our hybrids, the as-synthesized MOF@COF-TCNQ hybrid has been employed as an active material in supercapacitors. Electrochemical energy storage analysis revealed outstanding supercapacitor performance, as evidenced by a specific areal capacitance of 78.36 mF cm–2 and a high stack volumetric energy density of 4.46 F cm–3, with a capacitance retention of 86.4% after 2000 cycles completed at 0.2 A cm–2. DFT calculation results strongly indicate that the high capacitance of MOF@COF-TCNQ has a quantum capacitance origin. Our liquid-phase infiltration protocol of MOF@COF hybrids with redox-active molecules represents a efficacious approach to design functional porous hybrids. |
Lucherelli, M A; Qian, X; Weston, P; Eredia, M; Zhu, W; Samorì, P; Gao, H; Bianco, A; von dem Bussche, A Boron Nitride Nanosheets Can Induce Water Channels Across Lipid Bilayers Leading to Lysosomal Permeabilization Journal Article In: Adv. Mater., 33 (2103137), 2021. @article{Lucherelli2021, title = {Boron Nitride Nanosheets Can Induce Water Channels Across Lipid Bilayers Leading to Lysosomal Permeabilization}, author = {M. A. Lucherelli and X. Qian and P. Weston and M. Eredia and W. Zhu and P. Samorì and H. Gao and A. Bianco and A. von dem Bussche}, editor = {Wiley Online Library}, url = {https://doi.org/10.1002/adma.202103137}, year = {2021}, date = {2021-11-11}, journal = {Adv. Mater.}, volume = {33}, number = {2103137}, abstract = {Abstract While the interaction between 2D materials and cells is of key importance to the development of nanomedicines and safe applications of nanotechnology, still little is known about the biological interactions of many emerging 2D materials. Here, an investigation of how hexagonal boron nitride (hBN) interacts with the cell membrane is carried out by combining molecular dynamics (MD), liquid-phase exfoliation, and in vitro imaging methods. MD simulations reveal that a sharp hBN wedge can penetrate a lipid bilayer and form a cross-membrane water channel along its exposed polar edges, while a round hBN sheet does not exhibit this behavior. It is hypothesized that such water channels can facilitate cross-membrane transport, with important consequences including lysosomal membrane permeabilization, an emerging mechanism of cellular toxicity that involves the release of cathepsin B and generation of radical oxygen species leading to cell apoptosis. To test this hypothesis, two types of hBN nanosheets, one with a rhomboidal, cornered morphology and one with a round morphology, are prepared, and human lung epithelial cells are exposed to both materials. The cornered hBN with lateral polar edges results in a dose-dependent cytotoxic effect, whereas round hBN does not cause significant toxicity, thus confirming our premise. }, keywords = {}, pubstate = {published}, tppubtype = {article} } Abstract While the interaction between 2D materials and cells is of key importance to the development of nanomedicines and safe applications of nanotechnology, still little is known about the biological interactions of many emerging 2D materials. Here, an investigation of how hexagonal boron nitride (hBN) interacts with the cell membrane is carried out by combining molecular dynamics (MD), liquid-phase exfoliation, and in vitro imaging methods. MD simulations reveal that a sharp hBN wedge can penetrate a lipid bilayer and form a cross-membrane water channel along its exposed polar edges, while a round hBN sheet does not exhibit this behavior. It is hypothesized that such water channels can facilitate cross-membrane transport, with important consequences including lysosomal membrane permeabilization, an emerging mechanism of cellular toxicity that involves the release of cathepsin B and generation of radical oxygen species leading to cell apoptosis. To test this hypothesis, two types of hBN nanosheets, one with a rhomboidal, cornered morphology and one with a round morphology, are prepared, and human lung epithelial cells are exposed to both materials. The cornered hBN with lateral polar edges results in a dose-dependent cytotoxic effect, whereas round hBN does not cause significant toxicity, thus confirming our premise. |
Urbanos, F J; Gullace, S; Samorì, P Field-effect-transistor-based ion sensors: ultrasensitive mercury(II) detection via healing MoS2 defects Journal Article In: Nanoscale, 13 , pp. 19682–19689, 2021. @article{Urbanos2021, title = {Field-effect-transistor-based ion sensors: ultrasensitive mercury(II) detection via healing MoS2 defects}, author = {F. J. Urbanos and S. Gullace and P. Samorì}, editor = {Royal Society of Chemistry}, url = {https://doi.org/10.1039/d1nr05992k}, year = {2021}, date = {2021-11-09}, journal = {Nanoscale}, volume = {13}, pages = {19682–19689}, abstract = {The contamination of water with heavy metal ions represents a harsh environmental problem resulting from societal development. Among various hazardous compounds, mercury ions (Hg2+) surely belong to the most poisonous ones. Their accumulation in the human body results in health deterioration, affecting vital organs and eventually leading to chronic diseases, and, in the worst-case scenario, early death. High selectivity and sensitivity for the analyte of choice can be achieved in chemical sensing using suitable active materials capable of interacting at the supramolecular level with the chosen species. Among them, 2D transition metal dichalcogenides (TMDCs) have attracted great attention as sensory materials because of their unique physical and chemical properties, which are highly susceptible to environmental changes. In this work, we have fabricated MoS2-based field-effect transistors (FETs) and exploited them as platforms for Hg2+ sensing, relying on the affinity of heavy metal ions for both point defects in TMDCs and sulphur atoms in the MoS2 lattice. X-ray photoelectron spectroscopy characterization showed both a significant reduction of the defectiveness of MoS2 when exposed to Hg2+ with increasing concentration and a shift in the binding energy of 0.2 eV suggesting p-type doping of the 2D semiconductor. The efficient defect healing has been confirmed also by low-temperature photoluminescence measurements by monitoring the attenuation of defect-related bands after Hg2+ exposure. Transfer characteristics in MoS2 FETs provided further evidence that Hg2+ acts as a p-dopant of MoS2. Interestingly, we observed a strict correlation of doping with the concentration of Hg2+, following a semi-log trend. Hg2+ concentrations as low as 1 pM can be detected, being way below the limits imposed by health regulations. Electrical characterization also revealed that our sensor can be efficiently washed and used multiple times. Moreover, the developed devices displayed a markedly high selectivity for Hg2+ against other metal ions as ruled by soft/soft interaction among chemical systems with appropriate redox potentials, being a generally applicable approach to develop chemical sensing devices combining high sensitivity, selectivity and reversibility, to meet technological needs.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The contamination of water with heavy metal ions represents a harsh environmental problem resulting from societal development. Among various hazardous compounds, mercury ions (Hg2+) surely belong to the most poisonous ones. Their accumulation in the human body results in health deterioration, affecting vital organs and eventually leading to chronic diseases, and, in the worst-case scenario, early death. High selectivity and sensitivity for the analyte of choice can be achieved in chemical sensing using suitable active materials capable of interacting at the supramolecular level with the chosen species. Among them, 2D transition metal dichalcogenides (TMDCs) have attracted great attention as sensory materials because of their unique physical and chemical properties, which are highly susceptible to environmental changes. In this work, we have fabricated MoS2-based field-effect transistors (FETs) and exploited them as platforms for Hg2+ sensing, relying on the affinity of heavy metal ions for both point defects in TMDCs and sulphur atoms in the MoS2 lattice. X-ray photoelectron spectroscopy characterization showed both a significant reduction of the defectiveness of MoS2 when exposed to Hg2+ with increasing concentration and a shift in the binding energy of 0.2 eV suggesting p-type doping of the 2D semiconductor. The efficient defect healing has been confirmed also by low-temperature photoluminescence measurements by monitoring the attenuation of defect-related bands after Hg2+ exposure. Transfer characteristics in MoS2 FETs provided further evidence that Hg2+ acts as a p-dopant of MoS2. Interestingly, we observed a strict correlation of doping with the concentration of Hg2+, following a semi-log trend. Hg2+ concentrations as low as 1 pM can be detected, being way below the limits imposed by health regulations. Electrical characterization also revealed that our sensor can be efficiently washed and used multiple times. Moreover, the developed devices displayed a markedly high selectivity for Hg2+ against other metal ions as ruled by soft/soft interaction among chemical systems with appropriate redox potentials, being a generally applicable approach to develop chemical sensing devices combining high sensitivity, selectivity and reversibility, to meet technological needs. |
Liu, Z; Qiu, H; Fu, S; Wang, C; Yao, X; Dixon, A G; Campidelli, S; Pavlica, E; Bratina, G; Zhao, S; Rondin, L; Lauret, J -S; Narita, A; Bonn, M; Müllen, K; Ciesielski, A; H. I. Wang, ; Samorì, P Solution-Processed Graphene–Nanographene van der Waals Heterostructures for Photodetectors with Efficient and Ultralong Charge Separation Journal Article In: J. Am. Chem. Soc., 143 , pp. 17109–17116, 2021. @article{Liu2021, title = {Solution-Processed Graphene–Nanographene van der Waals Heterostructures for Photodetectors with Efficient and Ultralong Charge Separation}, author = {Z. Liu and H. Qiu and S. Fu and C. Wang and X. Yao and A. G. Dixon and S. Campidelli and E. Pavlica and G. Bratina and S. Zhao and L. Rondin and J.-S. Lauret and A. Narita and M. Bonn and K. Müllen and A. Ciesielski and H. I. Wang, and P. Samorì}, editor = {ACS Publcation}, url = {https://doi.org/10.1021/jacs.1c07615}, year = {2021}, date = {2021-10-07}, journal = {J. Am. Chem. Soc.}, volume = {143}, pages = {17109–17116}, abstract = {Sensitization of graphene with inorganic semiconducting nanostructures has been demonstrated as a powerful strategy to boost its optoelectronic performance. However, the limited tunability of optical properties and toxicity of metal cations in the inorganic sensitizers prohibits their widespread applications, and the in-depth understanding of the essential interfacial charge-transfer process within such hybrid systems remains elusive. Here, we design and develop high-quality nanographene (NG) dispersions with a large-scale production using high-shear mixing exfoliation. The physisorption of these NG molecules onto graphene gives rise to the formation of graphene–NG van der Waals heterostructures (VDWHs), characterized by strong interlayer coupling through π–π interactions. As a proof of concept, photodetectors fabricated on the basis of such VDWHs show ultrahigh responsivity up to 4.5 × 107 A/W and a specific detectivity reaching 4.6 × 1013 Jones, being competitive with the highest values obtained for graphene-based photodetectors. The outstanding device characteristics are attributed to the efficient transfer of photogenerated holes from NGs to graphene and the long-lived charge separation at graphene–NG interfaces (beyond 1 ns), as elucidated by ultrafast terahertz (THz) spectroscopy. These results demonstrate the great potential of such graphene–NG VDWHs as prototypical building blocks for high-performance, low-toxicity optoelectronics.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Sensitization of graphene with inorganic semiconducting nanostructures has been demonstrated as a powerful strategy to boost its optoelectronic performance. However, the limited tunability of optical properties and toxicity of metal cations in the inorganic sensitizers prohibits their widespread applications, and the in-depth understanding of the essential interfacial charge-transfer process within such hybrid systems remains elusive. Here, we design and develop high-quality nanographene (NG) dispersions with a large-scale production using high-shear mixing exfoliation. The physisorption of these NG molecules onto graphene gives rise to the formation of graphene–NG van der Waals heterostructures (VDWHs), characterized by strong interlayer coupling through π–π interactions. As a proof of concept, photodetectors fabricated on the basis of such VDWHs show ultrahigh responsivity up to 4.5 × 107 A/W and a specific detectivity reaching 4.6 × 1013 Jones, being competitive with the highest values obtained for graphene-based photodetectors. The outstanding device characteristics are attributed to the efficient transfer of photogenerated holes from NGs to graphene and the long-lived charge separation at graphene–NG interfaces (beyond 1 ns), as elucidated by ultrafast terahertz (THz) spectroscopy. These results demonstrate the great potential of such graphene–NG VDWHs as prototypical building blocks for high-performance, low-toxicity optoelectronics. |
Qiu, H; Herder, M; Hecht, S; Samorì, P Ternary-Responsive Field-Effect Transistors and Multilevel Memories Based on Asymmetrically Functionalized Janus Few-Layer WSe2 Journal Article In: Adv. Funct. Mater., 31 (2102721), 2021. @article{Qiu2021b, title = {Ternary-Responsive Field-Effect Transistors and Multilevel Memories Based on Asymmetrically Functionalized Janus Few-Layer WSe2}, author = {H. Qiu and M. Herder and S. Hecht and P. Samorì}, editor = {Wiley Online Library}, url = {https://doi.org/10.1002/adfm.202102721}, year = {2021}, date = {2021-09-02}, journal = {Adv. Funct. Mater.}, volume = {31}, number = {2102721}, abstract = {Hybrids composed of 2D transition metal dichalcogenides with stimuli-responsive molecules are prototypical components for the development of multifunctional field-effect transistors (FETs), whose output currents can be remotely controlled by external inputs. Herein, ternary-responsive FETs based on a few-layer WSe2 are realized by decorating the two opposite surfaces of the 2D semiconductor with different stimuli-responsive molecules in an asymmetric fashion: the bottom surface is interfaced with a photochromic diarylethene film and the top surface with a ferroelectric poly(vinylidene fluoride–trifluoroethylene) layer. This novel Janus ternary device architecture shows superior functional complexity compared with normal mono-stimuli-responsive FETs. The synergy between the two molecularly induced effects enables the devices to respond orthogonally to an electric field and light irradiation, with an enhanced output current modulation efficiency of 87%. The 9 ferroelectric and 84 photo-generated states ensure 756 current levels in a single device. The over 10 cycles of cyclic endurance and more than 1000 h of retention time confirm the reliability of each state, implementing the demand for high-density non-volatile memories, as well as enriching the diversification in “More than Moore” technologies.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Hybrids composed of 2D transition metal dichalcogenides with stimuli-responsive molecules are prototypical components for the development of multifunctional field-effect transistors (FETs), whose output currents can be remotely controlled by external inputs. Herein, ternary-responsive FETs based on a few-layer WSe2 are realized by decorating the two opposite surfaces of the 2D semiconductor with different stimuli-responsive molecules in an asymmetric fashion: the bottom surface is interfaced with a photochromic diarylethene film and the top surface with a ferroelectric poly(vinylidene fluoride–trifluoroethylene) layer. This novel Janus ternary device architecture shows superior functional complexity compared with normal mono-stimuli-responsive FETs. The synergy between the two molecularly induced effects enables the devices to respond orthogonally to an electric field and light irradiation, with an enhanced output current modulation efficiency of 87%. The 9 ferroelectric and 84 photo-generated states ensure 756 current levels in a single device. The over 10 cycles of cyclic endurance and more than 1000 h of retention time confirm the reliability of each state, implementing the demand for high-density non-volatile memories, as well as enriching the diversification in “More than Moore” technologies. |
Gullace, S; Montes-García, V; Martín, V; Larios, D; Consolaro, Girelli V; Obelleiro, F; Calogero, G; Casalini, S; Samorì, P Universal Fabrication of Highly Efficient Plasmonic Thin-Films for Label-Free SERS Detection Journal Article In: Small, 17 (2100755), 2021. @article{Gullace2021, title = {Universal Fabrication of Highly Efficient Plasmonic Thin-Films for Label-Free SERS Detection}, author = {S. Gullace and V. Montes-García and V. Martín and D. Larios and V. Girelli Consolaro and F. Obelleiro and G. Calogero and S. Casalini and P. Samorì}, editor = {Wiley Online Library}, url = {https://doi.org/10.1002/smll.202100755}, year = {2021}, date = {2021-08-19}, journal = {Small}, volume = {17}, number = {2100755}, abstract = {The development of novel, highly efficient, reliable, and robust surface enhanced Raman scattering (SERS) substrates containing a large number of hot spots with programmed size, geometry, and density is extremely interesting since it allows the sensing of numerous (bio-)chemical species. Herein, an extremely reliable, easy to fabricate, and label-free SERS sensing platform based on metal nanoparticles (NPs) thin-film is developed by the layer-by-layer growth mediated by polyelectrolytes. A systematic study of the effect of NP composition and size, as well as the number of deposition steps on the substrate's performance, is accomplished by monitoring the SERS enhancement of 1-naphtalenethiol (532 nm excitation). Distinct evidence of the key role played by the interlayer (poly(diallyldimethylammonium chloride) (PDDA) or PDDA-functionalized graphene oxide (GO@PDDA)) on the overall SERS efficiency of the plasmonic platforms is provided, revealing in the latter the formation of more uniform hot spots by regulating the interparticle distances to 5 ± 1 nm. The SERS platform efficiency is demonstrated via its high analytical enhancement factor (≈106) and the detection of a prototypical substance(tamoxifen), both in Milli-Q water and in a real matrix, viz. tap water, opening perspectives towards the use of plasmonic platforms for future high-performance sensing applications.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The development of novel, highly efficient, reliable, and robust surface enhanced Raman scattering (SERS) substrates containing a large number of hot spots with programmed size, geometry, and density is extremely interesting since it allows the sensing of numerous (bio-)chemical species. Herein, an extremely reliable, easy to fabricate, and label-free SERS sensing platform based on metal nanoparticles (NPs) thin-film is developed by the layer-by-layer growth mediated by polyelectrolytes. A systematic study of the effect of NP composition and size, as well as the number of deposition steps on the substrate's performance, is accomplished by monitoring the SERS enhancement of 1-naphtalenethiol (532 nm excitation). Distinct evidence of the key role played by the interlayer (poly(diallyldimethylammonium chloride) (PDDA) or PDDA-functionalized graphene oxide (GO@PDDA)) on the overall SERS efficiency of the plasmonic platforms is provided, revealing in the latter the formation of more uniform hot spots by regulating the interparticle distances to 5 ± 1 nm. The SERS platform efficiency is demonstrated via its high analytical enhancement factor (≈106) and the detection of a prototypical substance(tamoxifen), both in Milli-Q water and in a real matrix, viz. tap water, opening perspectives towards the use of plasmonic platforms for future high-performance sensing applications. |
