2017 |
Sauvage, Jean-Pierre From Chemical Topology to Molecular Machines (Nobel Lecture) Journal Article In: ANGEWANDTE CHEMIE-INTERNATIONAL EDITION, 56 (37, SI), pp. 11080–11093, 2017, ISSN: 1433-7851. @article{sauvage_chemical_2017, title = {From Chemical Topology to Molecular Machines (Nobel Lecture)}, author = {Sauvage, Jean-Pierre}, doi = {10.1002/anie.201702992}, issn = {1433-7851}, year = {2017}, date = {2017-09-01}, journal = {ANGEWANDTE CHEMIE-INTERNATIONAL EDITION}, volume = {56}, number = {37, SI}, pages = {11080--11093}, abstract = {To a large extent, the field of “molecular machines” started after several groups were able to prepare, reasonably easily, interlocking ring compounds (named catenanes for compounds consisting of interlocking rings and rotaxanes for rings threaded by molecular filaments or axes). Important families of molecular machines not belonging to the interlocking world were also designed, prepared, and studied but, for most of them, their elaboration was more recent than that of catenanes or rotaxanes. Since the creation of interlocking ring molecules is so important in relation to the molecular machinery area, we will start with this aspect of our work. The second part will naturally be devoted to the dynamic properties of such systems and to the compounds for which motions can be directed in a controlled manner from the outside, that is, molecular machines. We will restrict our discussion to a very limited number of examples which we consider as particularly representative of the field.}, keywords = {}, pubstate = {published}, tppubtype = {article} } To a large extent, the field of “molecular machines” started after several groups were able to prepare, reasonably easily, interlocking ring compounds (named catenanes for compounds consisting of interlocking rings and rotaxanes for rings threaded by molecular filaments or axes). Important families of molecular machines not belonging to the interlocking world were also designed, prepared, and studied but, for most of them, their elaboration was more recent than that of catenanes or rotaxanes. Since the creation of interlocking ring molecules is so important in relation to the molecular machinery area, we will start with this aspect of our work. The second part will naturally be devoted to the dynamic properties of such systems and to the compounds for which motions can be directed in a controlled manner from the outside, that is, molecular machines. We will restrict our discussion to a very limited number of examples which we consider as particularly representative of the field. |
Squillaci, Marco A; Markiewicz, Grzegorz ; Walczak, Anna ; Ciesielski, Artur ; Stefankiewicz, Artur R; Samori, Paolo Self-organization of amino-acid-derived NDI assemblies into a nanofibrillar superstructure with humidity sensitive n-type semiconducting properties Journal Article In: CHEMICAL COMMUNICATIONS, 53 (70), pp. 9713–9716, 2017, ISSN: 1359-7345. @article{squillaci_self-organization_2017, title = {Self-organization of amino-acid-derived NDI assemblies into a nanofibrillar superstructure with humidity sensitive n-type semiconducting properties}, author = {Squillaci, Marco A. and Markiewicz, Grzegorz and Walczak, Anna and Ciesielski, Artur and Stefankiewicz, Artur R. and Samori, Paolo}, doi = {10.1039/c7cc04822j}, issn = {1359-7345}, year = {2017}, date = {2017-09-01}, journal = {CHEMICAL COMMUNICATIONS}, volume = {53}, number = {70}, pages = {9713--9716}, abstract = {The hierarchical self-assembly of L-tyrosine substituted naphthalenediimide has been explored in solution by NMR spectroscopy and in the solid-state by atomic force microscopy. Spontaneous non-covalent polymerisation led to the formation of a three-dimensional fibre-like supramolecular polymer with n-type semiconducting properties.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The hierarchical self-assembly of L-tyrosine substituted naphthalenediimide has been explored in solution by NMR spectroscopy and in the solid-state by atomic force microscopy. Spontaneous non-covalent polymerisation led to the formation of a three-dimensional fibre-like supramolecular polymer with n-type semiconducting properties. |
Kelley, Matthew S; Shelby, Megan L; Mara, Michael W; Haldrup, Kristoffer ; Hayes, Dugan ; Hadt, Ryan G; Zhang, Xiaoyi ; Stickrath, Andrew B; Ruppert, Romain ; Sauvage, Jean-Pierre ; Zhu, Diling ; Lemke, Henrik T; Chollet, Matthieu ; Schatz, George C; Chen, Lin X Ultrafast dynamics of two copper bisphenanthroline complexes measured by x-ray transient absorption spectroscopy Journal Article In: JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS, 50 (15), 2017, ISSN: 0953-4075. @article{kelley_ultrafast_2017, title = {Ultrafast dynamics of two copper bisphenanthroline complexes measured by x-ray transient absorption spectroscopy}, author = {Kelley, Matthew S. and Shelby, Megan L. and Mara, Michael W. and Haldrup, Kristoffer and Hayes, Dugan and Hadt, Ryan G. and Zhang, Xiaoyi and Stickrath, Andrew B. and Ruppert, Romain and Sauvage, Jean-Pierre and Zhu, Diling and Lemke, Henrik T. and Chollet, Matthieu and Schatz, George C. and Chen, Lin X.}, doi = {10.1088/1361-6455/aa7b97}, issn = {0953-4075}, year = {2017}, date = {2017-08-01}, journal = {JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS}, volume = {50}, number = {15}, abstract = {Ultrafast structural dynamics of the metal to ligand charge transfer (MLCT) states of two copper bis-phenanthroline complexes were captured by using x-ray transient absorption (XTA) spectroscopy at the Linac Coherent Light Source and further described by theoretical calculations. These complexes have the general formula [Cu(I)(R)(2)](+), where R = 2,9-dimethyl-1,10-phenanthroline (dmp) and 2,9-diphenyl-1,10-phenanthroline disulfonic acid disodium salt (dpps). [Cu(I)(dmp)(2)](+) has methyl groups at the 2,9 positions of phenanthroline (phen) and adopts a pseudo-tetrahedral geometry. In contrast, [Cu(I)(dpps)(2)](+) possesses two bulky phenyl-sulfonate groups attached to each phen ligand that force the molecule to adopt a flattened tetrahedral geometry in the ground state. Previously, optical transient absorption (OTA) and synchrotron based XTA experiments with 100 ps time resolution have been employed to study the relationship between structural distortions and excited state relaxation pathways in the two complexes. However, the dynamics of the MLCT transition during the first few picoseconds after excitation in these complexes remained unclear because of limitations in element specificity in OTA and in the time resolution of synchrotron sources in XTA. In this experiment, the local coordination geometry and oxidation state of copper were probed with a temporal resolution of similar to 300 fs. Unexpectedly, the depletion of the Cu(I) signal due to the MLCT transition was found to be non-impulsive in the case of [Cu(I)(dpps)(2)](+) with a time constant of 0.6 ps, while the Cu(I) depletion in [Cu(I)(dmp)(2)](+) was instantaneous within the 300 fs instrument response time. The slower Cu(I) depletion kinetics in [Cu(I)(dpps)(2)](+), previously unobserved in femtosecond OTA experiments, is likely due to intramolecular motions on the sub-picosecond time scale that could alter the localization of the transferred electron in the phen ligands.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Ultrafast structural dynamics of the metal to ligand charge transfer (MLCT) states of two copper bis-phenanthroline complexes were captured by using x-ray transient absorption (XTA) spectroscopy at the Linac Coherent Light Source and further described by theoretical calculations. These complexes have the general formula [Cu(I)(R)(2)](+), where R = 2,9-dimethyl-1,10-phenanthroline (dmp) and 2,9-diphenyl-1,10-phenanthroline disulfonic acid disodium salt (dpps). [Cu(I)(dmp)(2)](+) has methyl groups at the 2,9 positions of phenanthroline (phen) and adopts a pseudo-tetrahedral geometry. In contrast, [Cu(I)(dpps)(2)](+) possesses two bulky phenyl-sulfonate groups attached to each phen ligand that force the molecule to adopt a flattened tetrahedral geometry in the ground state. Previously, optical transient absorption (OTA) and synchrotron based XTA experiments with 100 ps time resolution have been employed to study the relationship between structural distortions and excited state relaxation pathways in the two complexes. However, the dynamics of the MLCT transition during the first few picoseconds after excitation in these complexes remained unclear because of limitations in element specificity in OTA and in the time resolution of synchrotron sources in XTA. In this experiment, the local coordination geometry and oxidation state of copper were probed with a temporal resolution of similar to 300 fs. Unexpectedly, the depletion of the Cu(I) signal due to the MLCT transition was found to be non-impulsive in the case of [Cu(I)(dpps)(2)](+) with a time constant of 0.6 ps, while the Cu(I) depletion in [Cu(I)(dmp)(2)](+) was instantaneous within the 300 fs instrument response time. The slower Cu(I) depletion kinetics in [Cu(I)(dpps)(2)](+), previously unobserved in femtosecond OTA experiments, is likely due to intramolecular motions on the sub-picosecond time scale that could alter the localization of the transferred electron in the phen ligands. |
Kulchat, Sirinan ; Chaur, Manuel N; Lehn, Jean-Marie Kinetic Selectivity and Thermodynamic Features of Competitive Imine Formation in Dynamic Covalent Chemistry Journal Article In: CHEMISTRY-A EUROPEAN JOURNAL, 23 (46), pp. 11108–11118, 2017, ISSN: 0947-6539. @article{kulchat_kinetic_2017, title = {Kinetic Selectivity and Thermodynamic Features of Competitive Imine Formation in Dynamic Covalent Chemistry}, author = {Kulchat, Sirinan and Chaur, Manuel N. and Lehn, Jean-Marie}, doi = {10.1002/chem.201702088}, issn = {0947-6539}, year = {2017}, date = {2017-08-01}, journal = {CHEMISTRY-A EUROPEAN JOURNAL}, volume = {23}, number = {46}, pages = {11108--11118}, abstract = {The kinetic and thermodynamic selectivities of imine formation have been investigated for several dynamic covalent libraries of aldehydes and amines. Two systems were examined, involving the reaction of different types of primary amino groups (aliphatic amines, alkoxy-amines, hydrazides and hydrazines) with two types of aldehydes, sulfobenzaldehyde and pyridoxal phosphate in aqueous solution at different pD (5.0, 8.5, 11.4) on one hand, 2-pyridinecarboxaldehyde and salicylaldehyde in organic solvents on the other hand. The reactions were performed separately for given amine/aldehyde pairs as well as in competitive conditions between an aldehyde and a mixture of amines. In the latter case, the time evolution of the dynamic covalent libraries generated was followed, taking into consideration the operation of both kinetic and thermodynamic selectivities. The results showed that, in aqueous solution, the imine of the aliphatic amine was not stable, but oxime and hydrazone formed well in a pH dependent way. On the other hand, in organic solvents, the kinetic product was the imine derived from an aliphatic amine and the thermodynamic products were oxime and hydrazone. The insights gained from these experiments provide a basis for the implementation of imine formation in selective derivatization of mono-amines in mixtures as well as of polyfunctional compounds presenting different types of amino groups. They may in principle be extended to other dynamic covalent chemistry systems.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The kinetic and thermodynamic selectivities of imine formation have been investigated for several dynamic covalent libraries of aldehydes and amines. Two systems were examined, involving the reaction of different types of primary amino groups (aliphatic amines, alkoxy-amines, hydrazides and hydrazines) with two types of aldehydes, sulfobenzaldehyde and pyridoxal phosphate in aqueous solution at different pD (5.0, 8.5, 11.4) on one hand, 2-pyridinecarboxaldehyde and salicylaldehyde in organic solvents on the other hand. The reactions were performed separately for given amine/aldehyde pairs as well as in competitive conditions between an aldehyde and a mixture of amines. In the latter case, the time evolution of the dynamic covalent libraries generated was followed, taking into consideration the operation of both kinetic and thermodynamic selectivities. The results showed that, in aqueous solution, the imine of the aliphatic amine was not stable, but oxime and hydrazone formed well in a pH dependent way. On the other hand, in organic solvents, the kinetic product was the imine derived from an aliphatic amine and the thermodynamic products were oxime and hydrazone. The insights gained from these experiments provide a basis for the implementation of imine formation in selective derivatization of mono-amines in mixtures as well as of polyfunctional compounds presenting different types of amino groups. They may in principle be extended to other dynamic covalent chemistry systems. |
Hsu, Chien-Wei ; Longhi, Elena ; Sinn, Stephan ; Hawes, Chris S; Young, David C; Kruger, Paul E; De Cola, Luisa Pyrazolo[4,3-h]quinoline Ligand-Based Iridium(III) Complexes for Electrochemiluminescence Journal Article In: CHEMISTRY-AN ASIAN JOURNAL, 12 (13, SI), pp. 1649–1658, 2017, ISSN: 1861-4728. @article{hsu_pyrazolo[43-h]quinoline_2017, title = {Pyrazolo[4,3-h]quinoline Ligand-Based Iridium(III) Complexes for Electrochemiluminescence}, author = {Hsu, Chien-Wei and Longhi, Elena and Sinn, Stephan and Hawes, Chris S. and Young, David C. and Kruger, Paul E. and De Cola, Luisa}, doi = {10.1002/asia.201700556}, issn = {1861-4728}, year = {2017}, date = {2017-07-01}, journal = {CHEMISTRY-AN ASIAN JOURNAL}, volume = {12}, number = {13, SI}, pages = {1649--1658}, abstract = {Electrochemiluminescence (ECL) based on [Ru(bpy)(3)](2+) systems is widely utilized for immunoassays. In order to extend the promising potential of ECL-based applications, Ir-III complexes have recently attracted attention as probes because of their excellent luminescent properties and tunable emission wavelength. Here we describe a series of Ir complexes using a large pi-conjugated ligand and different ancillary chelates. The complexes synthesized have been chemically and spectroscopically characterized and used for ECL measurements with annihilation and co-reactant methods. One of the Ir-III complexes investigated exhibits the brightest, ever reported, ECL efficiency in acetonitrile employing the benzoyl peroxide (BPO) co-reactant method.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Electrochemiluminescence (ECL) based on [Ru(bpy)(3)](2+) systems is widely utilized for immunoassays. In order to extend the promising potential of ECL-based applications, Ir-III complexes have recently attracted attention as probes because of their excellent luminescent properties and tunable emission wavelength. Here we describe a series of Ir complexes using a large pi-conjugated ligand and different ancillary chelates. The complexes synthesized have been chemically and spectroscopically characterized and used for ECL measurements with annihilation and co-reactant methods. One of the Ir-III complexes investigated exhibits the brightest, ever reported, ECL efficiency in acetonitrile employing the benzoyl peroxide (BPO) co-reactant method. |
Schmidtgall, Boris ; Chaloin, Olivier ; Bauer, Valentin ; Sumyk, Manuela ; Birck, Catherine ; Torbeev, Vladimir Dissecting mechanism of coupled folding and binding of an intrinsically disordered protein by chemical synthesis of conformationally constrained analogues Journal Article In: CHEMICAL COMMUNICATIONS, 53 (53), pp. 7369–7372, 2017, ISSN: 1359-7345. @article{schmidtgall_dissecting_2017, title = {Dissecting mechanism of coupled folding and binding of an intrinsically disordered protein by chemical synthesis of conformationally constrained analogues}, author = {Schmidtgall, Boris and Chaloin, Olivier and Bauer, Valentin and Sumyk, Manuela and Birck, Catherine and Torbeev, Vladimir}, doi = {10.1039/c7cc02276j}, issn = {1359-7345}, year = {2017}, date = {2017-07-01}, journal = {CHEMICAL COMMUNICATIONS}, volume = {53}, number = {53}, pages = {7369--7372}, abstract = {Non-canonical alpha-methyl amino acids were incorporated at various sites in the sequence of intrinsically disordered activation domain from the p160 transcriptional co-activator (ACTR) to facilitate the formation of alpha-helical structures. Kinetic and thermodynamic data confirm the induced fit mechanism of complex formation between the synthesized ACTR variants and the nuclear co-activator binding domain (NCBD).}, keywords = {}, pubstate = {published}, tppubtype = {article} } Non-canonical alpha-methyl amino acids were incorporated at various sites in the sequence of intrinsically disordered activation domain from the p160 transcriptional co-activator (ACTR) to facilitate the formation of alpha-helical structures. Kinetic and thermodynamic data confirm the induced fit mechanism of complex formation between the synthesized ACTR variants and the nuclear co-activator binding domain (NCBD). |
Guingo, Geoffrey ; Sauvage, Basile ; Dischler, Jean-Michel ; Cani, Marie-Paule Bi-Layer textures: a Model for Synthesis and Deformation of Composite Textures Journal Article In: COMPUTER GRAPHICS FORUM, 36 (4), pp. 111–122, 2017, ISSN: 0167-7055. @article{guingo_bi-layer_2017, title = {Bi-Layer textures: a Model for Synthesis and Deformation of Composite Textures}, author = {Guingo, Geoffrey and Sauvage, Basile and Dischler, Jean-Michel and Cani, Marie-Paule}, doi = {10.1111/cgf.13229}, issn = {0167-7055}, year = {2017}, date = {2017-07-01}, journal = {COMPUTER GRAPHICS FORUM}, volume = {36}, number = {4}, pages = {111--122}, abstract = {We propose a bi-layer representation for textures which is suitable for on-the-fly synthesis of unbounded textures from an input exemplar. The goal is to improve the variety of outputs while preserving plausible small-scale details. The insight is that many natural textures can be decomposed into a series of fine scale Gaussian patterns which have to be faithfully reproduced, and some non-homogeneous, larger scale structure which can be deformed to add variety. Our key contribution is a novel, bi-layer representation for such textures. It includes a model for spatially-varying Gaussian noise, together with a mechanism enabling synchronization with a structure layer. We propose an automatic method to instantiate our bi-layer model from an input exemplar. At the synthesis stage, the two layers are generated independently, synchronized and added, preserving the consistency of details even when the structure layer has been deformed to increase variety. We show on a variety of complex, real textures, that our method reduces repetition artifacts while preserving a coherent appearance.}, keywords = {}, pubstate = {published}, tppubtype = {article} } We propose a bi-layer representation for textures which is suitable for on-the-fly synthesis of unbounded textures from an input exemplar. The goal is to improve the variety of outputs while preserving plausible small-scale details. The insight is that many natural textures can be decomposed into a series of fine scale Gaussian patterns which have to be faithfully reproduced, and some non-homogeneous, larger scale structure which can be deformed to add variety. Our key contribution is a novel, bi-layer representation for such textures. It includes a model for spatially-varying Gaussian noise, together with a mechanism enabling synchronization with a structure layer. We propose an automatic method to instantiate our bi-layer model from an input exemplar. At the synthesis stage, the two layers are generated independently, synchronized and added, preserving the consistency of details even when the structure layer has been deformed to increase variety. We show on a variety of complex, real textures, that our method reduces repetition artifacts while preserving a coherent appearance. |
Eredia, Matilde ; Bertolazzi, Simone ; Leydecker, Tim ; El Garah, Mohamed ; Janica, Iwona ; Melinte, Georgian ; Ersen, Ovidiu ; Ciesielski, Artur ; Samori, Paolo Morphology and Electronic Properties of Electrochemically Exfoliated Graphene Journal Article In: JOURNAL OF PHYSICAL CHEMISTRY LETTERS, 8 (14), pp. 3347–3355, 2017, ISSN: 1948-7185. @article{eredia_morphology_2017, title = {Morphology and Electronic Properties of Electrochemically Exfoliated Graphene}, author = {Eredia, Matilde and Bertolazzi, Simone and Leydecker, Tim and El Garah, Mohamed and Janica, Iwona and Melinte, Georgian and Ersen, Ovidiu and Ciesielski, Artur and Samori, Paolo}, doi = {10.1021/acs.jpclett.7b01301}, issn = {1948-7185}, year = {2017}, date = {2017-07-01}, journal = {JOURNAL OF PHYSICAL CHEMISTRY LETTERS}, volume = {8}, number = {14}, pages = {3347--3355}, abstract = {Electrochemically exfoliated graphene (EEG) possesses optical and electronic properties that are markedly different from those of the more explored graphene oxide in both its pristine and reduced forms. EEG also holds a unique advantage compared to other graphenes produced by exfoliation in liquid media: it can be obtained in large quantities in a short time. However, an in-depth understanding of the structure properties relationship of this material is still lacking. In this work, we report physicochemical characterization of EEG combined with an investigation of the electronic properties of this material carried out both at the single flake level and on the films. Additionally, we use for the first time microwave irradiation to reduce the EEG and demonstrate that the oxygen functionalities are not the bottleneck for charge transport in EEG, which is rather hindered by the presence of structural defects within the basal plane.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Electrochemically exfoliated graphene (EEG) possesses optical and electronic properties that are markedly different from those of the more explored graphene oxide in both its pristine and reduced forms. EEG also holds a unique advantage compared to other graphenes produced by exfoliation in liquid media: it can be obtained in large quantities in a short time. However, an in-depth understanding of the structure properties relationship of this material is still lacking. In this work, we report physicochemical characterization of EEG combined with an investigation of the electronic properties of this material carried out both at the single flake level and on the films. Additionally, we use for the first time microwave irradiation to reduce the EEG and demonstrate that the oxygen functionalities are not the bottleneck for charge transport in EEG, which is rather hindered by the presence of structural defects within the basal plane. |
Markiewicz, Grzegorz ; Pakulski, Dawid ; Galanti, Agostino ; Patroniak, Violetta ; Ciesielski, Artur ; Stefankiewicz, Artur R; Samori, Paolo Photoisomerisation and light-induced morphological switching of a polyoxometalate-azobenzene hybrid Journal Article In: CHEMICAL COMMUNICATIONS, 53 (53), pp. 7278–7281, 2017, ISSN: 1359-7345. @article{markiewicz_photoisomerisation_2017, title = {Photoisomerisation and light-induced morphological switching of a polyoxometalate-azobenzene hybrid}, author = {Markiewicz, Grzegorz and Pakulski, Dawid and Galanti, Agostino and Patroniak, Violetta and Ciesielski, Artur and Stefankiewicz, Artur R. and Samori, Paolo}, doi = {10.1039/c7cc01805c}, issn = {1359-7345}, year = {2017}, date = {2017-07-01}, journal = {CHEMICAL COMMUNICATIONS}, volume = {53}, number = {53}, pages = {7278--7281}, abstract = {The functionalization of a spherical Keplerate-type polyoxometalate Mo72V30 with a cationic azobenzene surfactant has been achieved through ionic self-assembly. The photoisomerisation reaction of this complex, which emerges in a light-triggered aggregation-disaggregation process, has been followed by H-1 NMR spectroscopy, dynamic light scattering, absorption spectroscopy and scanning electron microscopy analyses.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The functionalization of a spherical Keplerate-type polyoxometalate Mo72V30 with a cationic azobenzene surfactant has been achieved through ionic self-assembly. The photoisomerisation reaction of this complex, which emerges in a light-triggered aggregation-disaggregation process, has been followed by H-1 NMR spectroscopy, dynamic light scattering, absorption spectroscopy and scanning electron microscopy analyses. |
Mosciatti, Thomas ; Greco, Pierpaolo ; Leydecker, Tim ; Eredia, Matilde ; Biscarini, Fabio ; Samori, Paolo Asymmetric Injection in Organic Transistors via Direct SAM Functionalization of Source and Drain Electrodes Journal Article In: ACS OMEGA, 2 (7), pp. 3502–3508, 2017, ISSN: 2470-1343. @article{mosciatti_asymmetric_2017, title = {Asymmetric Injection in Organic Transistors via Direct SAM Functionalization of Source and Drain Electrodes}, author = {Mosciatti, Thomas and Greco, Pierpaolo and Leydecker, Tim and Eredia, Matilde and Biscarini, Fabio and Samori, Paolo}, doi = {10.1021/acsomega.7b00690}, issn = {2470-1343}, year = {2017}, date = {2017-07-01}, journal = {ACS OMEGA}, volume = {2}, number = {7}, pages = {3502--3508}, abstract = {The fabrication of organic optoelectronic devices integrating asymmetric electrodes enables optimal charge injection/extraction at each individual metal/semiconductor interface. This is key for applications in devices such as solar cells, light-emitting transistors, photodetectors, inverters, and sensors. Here, we describe a new method for the asymmetric functionalization of gold electrodes with different thiolated molecules as a viable route to obtain two electrodes with drastically different work function values. The process involves an ad hoc design of electrode geometry and the use of a polymeric mask to protect one electrode during the first functionalization step. Photoelectron yield ambient spectroscopy and X-ray photoelectron spectrometry were used to characterize the energetic properties and the composition of the asymmetrically functionalized electrodes. Finally, we used poly(3-hexylthiophene)-based organic thin-film transistors to show that the asymmetric electronic response stems from the different electronic structures of the functionalized electrodes.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The fabrication of organic optoelectronic devices integrating asymmetric electrodes enables optimal charge injection/extraction at each individual metal/semiconductor interface. This is key for applications in devices such as solar cells, light-emitting transistors, photodetectors, inverters, and sensors. Here, we describe a new method for the asymmetric functionalization of gold electrodes with different thiolated molecules as a viable route to obtain two electrodes with drastically different work function values. The process involves an ad hoc design of electrode geometry and the use of a polymeric mask to protect one electrode during the first functionalization step. Photoelectron yield ambient spectroscopy and X-ray photoelectron spectrometry were used to characterize the energetic properties and the composition of the asymmetrically functionalized electrodes. Finally, we used poly(3-hexylthiophene)-based organic thin-film transistors to show that the asymmetric electronic response stems from the different electronic structures of the functionalized electrodes. |
Zhong, Xiaolan ; Chervy, Thibault ; Zhang, Lei ; Thomas, Anoop ; George, Jino ; Genet, Cyriaque ; Hutchison, James A; Ebbesen, Thomas W Energy Transfer between Spatially Separated Entangled Molecules Journal Article In: ANGEWANDTE CHEMIE-INTERNATIONAL EDITION, 56 (31), pp. 9034–9038, 2017, ISSN: 1433-7851. @article{zhong_energy_2017, title = {Energy Transfer between Spatially Separated Entangled Molecules}, author = {Zhong, Xiaolan and Chervy, Thibault and Zhang, Lei and Thomas, Anoop and George, Jino and Genet, Cyriaque and Hutchison, James A. and Ebbesen, Thomas W.}, doi = {10.1002/anie.201703539}, issn = {1433-7851}, year = {2017}, date = {2017-07-01}, journal = {ANGEWANDTE CHEMIE-INTERNATIONAL EDITION}, volume = {56}, number = {31}, pages = {9034--9038}, abstract = {Light-matter strong coupling allows for the possibility of entangling the wave functions of different molecules through the light field. We hereby present direct evidence of non-radiative energy transfer well beyond the Forster limit for spatially separated donor and acceptor cyanine dyes strongly coupled to a cavity. The transient dynamics and the static spectra show an energy transfer efficiency approaching 37% for donor-acceptor distances textbackslashtextbackslashtextgreater= 100 nm. In such systems, the energy transfer process becomes independent of distance as long as the coupling strength is maintained. This is consistent with the entangled and delocalized nature of the polaritonic states.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Light-matter strong coupling allows for the possibility of entangling the wave functions of different molecules through the light field. We hereby present direct evidence of non-radiative energy transfer well beyond the Forster limit for spatially separated donor and acceptor cyanine dyes strongly coupled to a cavity. The transient dynamics and the static spectra show an energy transfer efficiency approaching 37% for donor-acceptor distances textbackslashtextbackslashtextgreater= 100 nm. In such systems, the energy transfer process becomes independent of distance as long as the coupling strength is maintained. This is consistent with the entangled and delocalized nature of the polaritonic states. |
Wang, Shan ; Yue, Liang ; Shpilt, Zohar ; Cecconello, Alessandro ; Kahn, Jason S; Lehn, Jean-Marie ; Willner, Itamar Controlling the Catalytic Functions of DNAzymes within Constitutional Dynamic Networks of DNA Nanostructures Journal Article In: JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 139 (28), pp. 9662–9671, 2017, ISSN: 0002-7863. @article{wang_controlling_2017, title = {Controlling the Catalytic Functions of DNAzymes within Constitutional Dynamic Networks of DNA Nanostructures}, author = {Wang, Shan and Yue, Liang and Shpilt, Zohar and Cecconello, Alessandro and Kahn, Jason S. and Lehn, Jean-Marie and Willner, Itamar}, doi = {10.1021/jacs.7b04531}, issn = {0002-7863}, year = {2017}, date = {2017-07-01}, journal = {JOURNAL OF THE AMERICAN CHEMICAL SOCIETY}, volume = {139}, number = {28}, pages = {9662--9671}, abstract = {Mimicking complex cellular dynamic chemical networks being up-regulated or down-regulated by external triggers is one of the challenges in systems chemistry. Constitutional dynamic networks (CDNs), composed of exchangeable components that respond to environmental triggers by self-adaption, provide general means to mimic biosystems. We use the structural and functional information encoded in nucleic acid nanostructures to construct effector (input)-triggered constitutional dynamic networks that reveal adaptable catalytic properties. Specifically, CDNs composed of four exchangeable constituents, AA', BA', AB', and BB', are constructed. In the presence of an effector (input) that controls the stability of one of the constituents, the input-guided up-regulation or down-regulation of the CDN's constituents proceeds. As effectors we apply the fuel-strand stabilization of one of the CDN constituents by the formation of the T-A-T triplex structure, or by the K+-ion-induced stabilization of one of the CDN constituents, via the formation of a K+-ion-stabilized G-quadruplex. Energetic stabilization of one of the CDN constituents leads to a new dynamically adapted network composed of up-regulated and down-regulated constituents. By applying counter triggers to the effector units, e.g., an antifuel strand or 18-crown-6-ether, reconfiguration to the original CDNs is demonstrated. The performance of the CDNs is followed by the catalytic activities of the constituents and by complementary quantitative gel electrophoresis experiments. The orthogonal triggered and switchable operation of the CDNs is highlighted.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Mimicking complex cellular dynamic chemical networks being up-regulated or down-regulated by external triggers is one of the challenges in systems chemistry. Constitutional dynamic networks (CDNs), composed of exchangeable components that respond to environmental triggers by self-adaption, provide general means to mimic biosystems. We use the structural and functional information encoded in nucleic acid nanostructures to construct effector (input)-triggered constitutional dynamic networks that reveal adaptable catalytic properties. Specifically, CDNs composed of four exchangeable constituents, AA', BA', AB', and BB', are constructed. In the presence of an effector (input) that controls the stability of one of the constituents, the input-guided up-regulation or down-regulation of the CDN's constituents proceeds. As effectors we apply the fuel-strand stabilization of one of the CDN constituents by the formation of the T-A-T triplex structure, or by the K+-ion-induced stabilization of one of the CDN constituents, via the formation of a K+-ion-stabilized G-quadruplex. Energetic stabilization of one of the CDN constituents leads to a new dynamically adapted network composed of up-regulated and down-regulated constituents. By applying counter triggers to the effector units, e.g., an antifuel strand or 18-crown-6-ether, reconfiguration to the original CDNs is demonstrated. The performance of the CDNs is followed by the catalytic activities of the constituents and by complementary quantitative gel electrophoresis experiments. The orthogonal triggered and switchable operation of the CDNs is highlighted. |
Meroz, Yasmine ; Ovchinnikov, Victor ; Karplus, Martin Coexisting origins of subdiffusion in internal dynamics of proteins Journal Article In: PHYSICAL REVIEW E, 95 (6), 2017, ISSN: 2470-0045. @article{meroz_coexisting_2017, title = {Coexisting origins of subdiffusion in internal dynamics of proteins}, author = {Meroz, Yasmine and Ovchinnikov, Victor and Karplus, Martin}, doi = {10.1103/PhysRevE.95.062403}, issn = {2470-0045}, year = {2017}, date = {2017-06-01}, journal = {PHYSICAL REVIEW E}, volume = {95}, number = {6}, abstract = {Subdiffusion in conformational dynamics of proteins is observed both experimentally and in simulations. Although its origin has been attributed to multiple mechanisms, including trapping on a rugged energy landscape, fractional Brownian noise, or a fractal topology of the energy landscape, it is unclear which of these, if any, is most relevant. To obtain insights into the actual mechanism, we introduce an analytically tractable hierarchical trapping model and apply it to molecular dynamics simulation trajectories of three proteins in solution. The analysis of the simulations introduces a subdiffusive exponent that varies with time and associates plateaus in the mean-squared displacement with traps on the energy landscape. This analysis permits us to separate the component of subdiffusion due to a trapping mechanism from that due to an underlying fluctuating process, such as fractional Brownian motion. The present results thus provide insights concerning the physical origin of subdiffusion in the dynamics of proteins.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Subdiffusion in conformational dynamics of proteins is observed both experimentally and in simulations. Although its origin has been attributed to multiple mechanisms, including trapping on a rugged energy landscape, fractional Brownian noise, or a fractal topology of the energy landscape, it is unclear which of these, if any, is most relevant. To obtain insights into the actual mechanism, we introduce an analytically tractable hierarchical trapping model and apply it to molecular dynamics simulation trajectories of three proteins in solution. The analysis of the simulations introduces a subdiffusive exponent that varies with time and associates plateaus in the mean-squared displacement with traps on the energy landscape. This analysis permits us to separate the component of subdiffusion due to a trapping mechanism from that due to an underlying fluctuating process, such as fractional Brownian motion. The present results thus provide insights concerning the physical origin of subdiffusion in the dynamics of proteins. |
Arnedo-Sanchez, Leticia ; Nonappa, ; Bhowmik, Sandip ; Hietala, Sami ; Puttreddy, Rakesh ; Lahtinen, Manu ; De Cola, Luisa ; Rissanen, Kari Rapid self-healing and anion selectivity in metallosupramolecular gels assisted by fluorine-fluorine interactions Journal Article In: DALTON TRANSACTIONS, 46 (22), pp. 7309–7316, 2017, ISSN: 1477-9226. @article{arnedo-sanchez_rapid_2017, title = {Rapid self-healing and anion selectivity in metallosupramolecular gels assisted by fluorine-fluorine interactions}, author = {Arnedo-Sanchez, Leticia and {Nonappa} and Bhowmik, Sandip and Hietala, Sami and Puttreddy, Rakesh and Lahtinen, Manu and De Cola, Luisa and Rissanen, Kari}, doi = {10.1039/c7dt00983f}, issn = {1477-9226}, year = {2017}, date = {2017-06-01}, journal = {DALTON TRANSACTIONS}, volume = {46}, number = {22}, pages = {7309--7316}, abstract = {Simple ML2 [M = Fe(II), Co(II), Ni(II)] complexes obtained from a perfluoroalkylamide derivative of 4-aminophenyl-2,2', 6,2'terpyridine spontaneously, yet anion selectively, selfassemble into gels, which manifest an unprecedented rapid gel strength recovery, viz. selfhealing, and thermal rearrangement in aqueous dimethyl sulfoxide. The key factor for gelation and rheological properties emerges from the fluorinefluorine interactions between the perfluorinated chains, as the corresponding hydrocarbon derivative did not form metallogels. The perfluoroterpyridine ligand alone formed single crystals, while its Fe(II), Co(II) or Ni(II) complexes underwent rapid gelation leading to highly entangled fibrillar networks visualized by electron microscopy. The thermodynamic parameters of gelation based on variable temperature NMR 1H and 19F resonances showed that gelation was enthalpically favourable and entropically disfavourable. The step strain rheological experiments revealed that the gels undergo rapid selfhealing and the morphological features, thermal stability and mechanical properties were found to depend on the nature of the metal ion.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Simple ML2 [M = Fe(II), Co(II), Ni(II)] complexes obtained from a perfluoroalkylamide derivative of 4-aminophenyl-2,2', 6,2'terpyridine spontaneously, yet anion selectively, selfassemble into gels, which manifest an unprecedented rapid gel strength recovery, viz. selfhealing, and thermal rearrangement in aqueous dimethyl sulfoxide. The key factor for gelation and rheological properties emerges from the fluorinefluorine interactions between the perfluorinated chains, as the corresponding hydrocarbon derivative did not form metallogels. The perfluoroterpyridine ligand alone formed single crystals, while its Fe(II), Co(II) or Ni(II) complexes underwent rapid gelation leading to highly entangled fibrillar networks visualized by electron microscopy. The thermodynamic parameters of gelation based on variable temperature NMR 1H and 19F resonances showed that gelation was enthalpically favourable and entropically disfavourable. The step strain rheological experiments revealed that the gels undergo rapid selfhealing and the morphological features, thermal stability and mechanical properties were found to depend on the nature of the metal ion. |
Strabler, C M; Sinn, S; Pehn, R; Pann, J; Dutzler, J; Viertl, W; Prock, J; Ehrmann, K; Weninger, A; Kopacka, H; De Cola, L; Brueggeller, P Stabilisation effects of phosphane ligands in the homogeneous approach of sunlight induced hydrogen production Journal Article In: FARADAY DISCUSSIONS, 198 , pp. 211–233, 2017, ISSN: 1359-6640. @article{strabler_stabilisation_2017, title = {Stabilisation effects of phosphane ligands in the homogeneous approach of sunlight induced hydrogen production}, author = {Strabler, C. M. and Sinn, S. and Pehn, R. and Pann, J. and Dutzler, J. and Viertl, W. and Prock, J. and Ehrmann, K. and Weninger, A. and Kopacka, H. and De Cola, L. and Brueggeller, P.}, doi = {10.1039/c6fd00210b}, issn = {1359-6640}, year = {2017}, date = {2017-06-01}, journal = {FARADAY DISCUSSIONS}, volume = {198}, pages = {211--233}, abstract = {Most of the systems for photochemical hydrogen production are not stable and suffer from decomposition. With bis(bidentate) tetraphosphane ligands the stability increases enormously, up to more than 1000 h. This stability was achieved with a system containing osmium(II) as a light harvesting antenna and palladium(II) as a water reduction catalyst connected with a bis(bidentate) phosphane ligand in one molecule with the chemical formula [Os(bpy)(2)(dppcb)Pd(dppm)](PF6)(4). With the help of electrochemical measurements as well as photophysical data and its single crystal X-ray structure, the electron transfer between the two active metal centres (light harvesting antenna, water reduction catalyst) was analysed. The distance between the two active metal centres was determined to be 7.396(1) angstrom. In a noble metal free combination of a copper based photosensitiser and a cobalt diimine-dioxime complex as water reduction catalyst a further stabilisation effect by the phosphane ligands is observed. With the help of triethylamine as a sacrificial donor in the presence of different monophosphane ligands it was possible to produce hydrogen with a turnover number of 1176. This completely novel combination is also able to produce hydrogen in a wide pH-range from pH = 7.0 to 12.5 with the maximum production at pH = 11.0. The influence of monophosphane ligands with different Tolman cone angles was investigated. Monophosphane ligands with a large Tolman cone angle (textbackslashtextbackslashtextgreater160 degrees) could not stabilise the intermediate of the cobalt based water reduction catalyst and so the turnover number is lower than for systems with an addition of monophosphane ligands with a Tolman cone angle smaller than 160 degrees. The role of the monophosphane ligand during sunlight-induced hydrogen production was analysed and these results were confirmed with DFT calculations. Furthermore the crystal structures of two important Co(I) intermediates, which are the catalytic active species during the catalytic pathway, were obtained. The exchange of PPh3 with other tertiary phosphane ligands can have a major impact on the activity, depending on the coordination properties. By an exchange of monophosphane ligands with functionalised phosphane ligands (hybrid ligands) the hydrogen production was raised 2.17 times.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Most of the systems for photochemical hydrogen production are not stable and suffer from decomposition. With bis(bidentate) tetraphosphane ligands the stability increases enormously, up to more than 1000 h. This stability was achieved with a system containing osmium(II) as a light harvesting antenna and palladium(II) as a water reduction catalyst connected with a bis(bidentate) phosphane ligand in one molecule with the chemical formula [Os(bpy)(2)(dppcb)Pd(dppm)](PF6)(4). With the help of electrochemical measurements as well as photophysical data and its single crystal X-ray structure, the electron transfer between the two active metal centres (light harvesting antenna, water reduction catalyst) was analysed. The distance between the two active metal centres was determined to be 7.396(1) angstrom. In a noble metal free combination of a copper based photosensitiser and a cobalt diimine-dioxime complex as water reduction catalyst a further stabilisation effect by the phosphane ligands is observed. With the help of triethylamine as a sacrificial donor in the presence of different monophosphane ligands it was possible to produce hydrogen with a turnover number of 1176. This completely novel combination is also able to produce hydrogen in a wide pH-range from pH = 7.0 to 12.5 with the maximum production at pH = 11.0. The influence of monophosphane ligands with different Tolman cone angles was investigated. Monophosphane ligands with a large Tolman cone angle (textbackslashtextbackslashtextgreater160 degrees) could not stabilise the intermediate of the cobalt based water reduction catalyst and so the turnover number is lower than for systems with an addition of monophosphane ligands with a Tolman cone angle smaller than 160 degrees. The role of the monophosphane ligand during sunlight-induced hydrogen production was analysed and these results were confirmed with DFT calculations. Furthermore the crystal structures of two important Co(I) intermediates, which are the catalytic active species during the catalytic pathway, were obtained. The exchange of PPh3 with other tertiary phosphane ligands can have a major impact on the activity, depending on the coordination properties. By an exchange of monophosphane ligands with functionalised phosphane ligands (hybrid ligands) the hydrogen production was raised 2.17 times. |
Sorrenti, Alessandro ; Leira-Iglesias, Jorge ; Sato, Akihiro ; Hermans, Thomas M Non-equilibrium steady states in supramolecular polymerization Journal Article In: NATURE COMMUNICATIONS, 8 , 2017, ISSN: 2041-1723. @article{sorrenti_non-equilibrium_2017, title = {Non-equilibrium steady states in supramolecular polymerization}, author = {Sorrenti, Alessandro and Leira-Iglesias, Jorge and Sato, Akihiro and Hermans, Thomas M.}, doi = {10.1038/ncomms15899}, issn = {2041-1723}, year = {2017}, date = {2017-06-01}, journal = {NATURE COMMUNICATIONS}, volume = {8}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Leydecker, Tim ; Favaretto, Laura ; Duong, Duc Trong ; Zappala, Gabriella ; Borjesson, Karl ; Licciardello, Antonino ; Salleo, Alberto ; Melucci, Manuela ; Orgiu, Emanuele ; Samori, Paolo Improving the electrical performance of solution processed oligothiophene thin-film transistors via structural similarity blending Journal Article In: JOURNAL OF MATERIALS CHEMISTRY C, 5 (21), pp. 5048–5054, 2017, ISSN: 2050-7526. @article{leydecker_improving_2017, title = {Improving the electrical performance of solution processed oligothiophene thin-film transistors via structural similarity blending}, author = {Leydecker, Tim and Favaretto, Laura and Duong, Duc Trong and Zappala, Gabriella and Borjesson, Karl and Licciardello, Antonino and Salleo, Alberto and Melucci, Manuela and Orgiu, Emanuele and Samori, Paolo}, doi = {10.1039/c7tc00748e}, issn = {2050-7526}, year = {2017}, date = {2017-06-01}, journal = {JOURNAL OF MATERIALS CHEMISTRY C}, volume = {5}, number = {21}, pages = {5048--5054}, abstract = {Here we show that the blending of structurally similar oligothiophene molecules is an effective approach to improve the field-effect mobility and I-on/I-off as compared to single component based transistors. The effect of addition of each component is studied extensively using a wide array of methods such as X-ray diffraction, ToF-SIMS, and ambient UPS correlated with the electrical characterization.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Here we show that the blending of structurally similar oligothiophene molecules is an effective approach to improve the field-effect mobility and I-on/I-off as compared to single component based transistors. The effect of addition of each component is studied extensively using a wide array of methods such as X-ray diffraction, ToF-SIMS, and ambient UPS correlated with the electrical characterization. |
Zhang, Xiaoyan ; Samori, Paolo Graphene/Polymer Nanocomposites for Supercapacitors Journal Article In: CHEMNANOMAT, 3 (6, SI), pp. 362–372, 2017, ISSN: 2199-692X. @article{zhang_graphene/polymer_2017, title = {Graphene/Polymer Nanocomposites for Supercapacitors}, author = {Zhang, Xiaoyan and Samori, Paolo}, doi = {10.1002/cnma.201700055}, issn = {2199-692X}, year = {2017}, date = {2017-06-01}, journal = {CHEMNANOMAT}, volume = {3}, number = {6, SI}, pages = {362--372}, abstract = {The energy crisis and global warming are two of the greatest challenges that our society is facing nowadays, requiring an immediate solution that involves the development of clean, efficient, sustainable and cheap energy-storage devices. These energy-storage devices are highly desirable for applications in electrical vehicles, portable electronic devices, and power grids, etc. The electrochemical performance of the devices largely depends on the chemical compositions and structures of the electrode materials. Graphene/polymer hybrid nanocomposites have gained great attention as electrodes for energy storage because of their excellent mechanical, electrical and electrochemical properties, originating from the synergistic effect of the two components. In this review, we present a general overview and recent advances of graphene/polymer nanocomposites as high-performance electrode materials for supercapacitors. Major challenges to be tackled and future perspectives are also highlighted.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The energy crisis and global warming are two of the greatest challenges that our society is facing nowadays, requiring an immediate solution that involves the development of clean, efficient, sustainable and cheap energy-storage devices. These energy-storage devices are highly desirable for applications in electrical vehicles, portable electronic devices, and power grids, etc. The electrochemical performance of the devices largely depends on the chemical compositions and structures of the electrode materials. Graphene/polymer hybrid nanocomposites have gained great attention as electrodes for energy storage because of their excellent mechanical, electrical and electrochemical properties, originating from the synergistic effect of the two components. In this review, we present a general overview and recent advances of graphene/polymer nanocomposites as high-performance electrode materials for supercapacitors. Major challenges to be tackled and future perspectives are also highlighted. |
Yang, Sheng ; Ricciardulli, Antonio Gaetano ; Liu, Shaohua ; Dong, Renhao ; Lohe, Martin R; Becker, Alfons ; Squillaci, Marco A; Samori, Paolo ; Muellen, Klaus ; Feng, Xinliang Ultrafast Delamination of Graphite into High-Quality Graphene Using Alternating Currents Journal Article In: ANGEWANDTE CHEMIE-INTERNATIONAL EDITION, 56 (23), pp. 6669–6675, 2017, ISSN: 1433-7851. @article{yang_ultrafast_2017, title = {Ultrafast Delamination of Graphite into High-Quality Graphene Using Alternating Currents}, author = {Yang, Sheng and Ricciardulli, Antonio Gaetano and Liu, Shaohua and Dong, Renhao and Lohe, Martin R. and Becker, Alfons and Squillaci, Marco A. and Samori, Paolo and Muellen, Klaus and Feng, Xinliang}, doi = {10.1002/anie.201702076}, issn = {1433-7851}, year = {2017}, date = {2017-06-01}, journal = {ANGEWANDTE CHEMIE-INTERNATIONAL EDITION}, volume = {56}, number = {23}, pages = {6669--6675}, abstract = {To bridge the gap between laboratory-scale studies and commercial applications, mass production of high quality graphene is essential. A scalable exfoliation strategy towards the production of graphene sheets is presented that has excellent yield (ca. 75%, 1-3 layers), low defect density (a C/O ratio of 21.2), great solution-processability, and outstanding electronic properties (a hole mobility of 430 cm(2) V-1 s(-1)). By applying alternating currents, dual exfoliation at both graphite electrodes enables a high production rate exceeding 20 g h(-1) in laboratory tests. As a cathode material for lithium storage, graphene-wrapped LiFePO4 particles deliver a high capacity of 167 mAh g(-1) at 1C rate after 500 cycles.}, keywords = {}, pubstate = {published}, tppubtype = {article} } To bridge the gap between laboratory-scale studies and commercial applications, mass production of high quality graphene is essential. A scalable exfoliation strategy towards the production of graphene sheets is presented that has excellent yield (ca. 75%, 1-3 layers), low defect density (a C/O ratio of 21.2), great solution-processability, and outstanding electronic properties (a hole mobility of 430 cm(2) V-1 s(-1)). By applying alternating currents, dual exfoliation at both graphite electrodes enables a high production rate exceeding 20 g h(-1) in laboratory tests. As a cathode material for lithium storage, graphene-wrapped LiFePO4 particles deliver a high capacity of 167 mAh g(-1) at 1C rate after 500 cycles. |
Aliprandi, Alessandro ; Croisetu, Christelle M; Mauro, Matteo ; De Cola, Luisa Chiral Amplification by Self-Assembly of Neutral Luminescent Platinum(II) Complexes Journal Article In: CHEMISTRY-A EUROPEAN JOURNAL, 23 (25), pp. 5957–5961, 2017, ISSN: 0947-6539. @article{aliprandi_chiral_2017, title = {Chiral Amplification by Self-Assembly of Neutral Luminescent Platinum(II) Complexes}, author = {Aliprandi, Alessandro and Croisetu, Christelle M. and Mauro, Matteo and De Cola, Luisa}, doi = {10.1002/chem.201605103}, issn = {0947-6539}, year = {2017}, date = {2017-05-01}, journal = {CHEMISTRY-A EUROPEAN JOURNAL}, volume = {23}, number = {25}, pages = {5957--5961}, abstract = {Two novel enantiomerically pure chiral ligands and the corresponding neutral Pt-II complexes have been synthetized and characterized. The self-assembly properties of the complexes have been investigated using different morphological and photophysical techniques. The two enantiomeric complexes, 4a and 4b, show high tendency to self-assemble into chiral supramolecular aggregates with right (P) and left-handed (M) helical configurations, respectively, as proven by SEM and absorption circular dichroism. The formation of such organized structures is driven by the formation of metallophilic and - interactions between spatially close Pt complexes with an enhancement of the chiro-optical properties in the solid state.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Two novel enantiomerically pure chiral ligands and the corresponding neutral Pt-II complexes have been synthetized and characterized. The self-assembly properties of the complexes have been investigated using different morphological and photophysical techniques. The two enantiomeric complexes, 4a and 4b, show high tendency to self-assemble into chiral supramolecular aggregates with right (P) and left-handed (M) helical configurations, respectively, as proven by SEM and absorption circular dichroism. The formation of such organized structures is driven by the formation of metallophilic and - interactions between spatially close Pt complexes with an enhancement of the chiro-optical properties in the solid state. |
Ragni, R; Maiorano, V; Pugliese, M; Maggiore, A; Orselli, E; Babudri, F; Gigli, G; De Cola, L; Farinola, G M A highly fluorinated iridium complex as a blue-green emitting component for white electroluminescence Journal Article In: SYNTHETIC METALS, 227 , pp. 148–155, 2017, ISSN: 0379-6779. @article{ragni_highly_2017, title = {A highly fluorinated iridium complex as a blue-green emitting component for white electroluminescence}, author = {Ragni, R. and Maiorano, V. and Pugliese, M. and Maggiore, A. and Orselli, E. and Babudri, F. and Gigli, G. and De Cola, L. and Farinola, G. M.}, doi = {10.1016/j.synthmet.2017.04.002}, issn = {0379-6779}, year = {2017}, date = {2017-05-01}, journal = {SYNTHETIC METALS}, volume = {227}, pages = {148--155}, abstract = {A novel perfluorinated heteroleptic iridium complex, namely iridium(III)bis[2-(2,5,2',3',4',5',6'-heptafluorobiphenyl-4-yl)-pyridi nato-N,C2'] [3-(pentafluorophenyl)-pyridin-2-yl-1,2,4-triazolate] (Ir-F19), has been synthesized and characterized both in solution and in the solid state. The compound displays blue-green photoluminescence, with emission peaks at 480 and 512 nm and 68% quantum yield, in degassed acetonitrile solution. The use of this phosphor in blue and white organic light emitting devices (WOLEDs) has been investigated. Current efficiency of 8.3 cd/A at 100 cd/m(2) has been recorded for the blue emitting device whereas white electroluminescence with good color rendering index (CRI = 76) and CIE coordinates (0.43, 0.42) have been observed for a WOLED made of two stacked layers based on Ir-F19 and the commercial orange Ir (MDQ)(2)(acac) [bis(2-methyldibenzo[f,h]quinoxaline)(acetylacetonate)iridium(III)]. WOLED luminous efficiency of 10.5 cd/A at 100 cd/m(2), almost constant (10.1 cd/A) up to 1000 cd/m(2), indicates that Ir-F19 is a promising blue-green emitting component for white electroluminescence.}, keywords = {}, pubstate = {published}, tppubtype = {article} } A novel perfluorinated heteroleptic iridium complex, namely iridium(III)bis[2-(2,5,2',3',4',5',6'-heptafluorobiphenyl-4-yl)-pyridi nato-N,C2'] [3-(pentafluorophenyl)-pyridin-2-yl-1,2,4-triazolate] (Ir-F19), has been synthesized and characterized both in solution and in the solid state. The compound displays blue-green photoluminescence, with emission peaks at 480 and 512 nm and 68% quantum yield, in degassed acetonitrile solution. The use of this phosphor in blue and white organic light emitting devices (WOLEDs) has been investigated. Current efficiency of 8.3 cd/A at 100 cd/m(2) has been recorded for the blue emitting device whereas white electroluminescence with good color rendering index (CRI = 76) and CIE coordinates (0.43, 0.42) have been observed for a WOLED made of two stacked layers based on Ir-F19 and the commercial orange Ir (MDQ)(2)(acac) [bis(2-methyldibenzo[f,h]quinoxaline)(acetylacetonate)iridium(III)]. WOLED luminous efficiency of 10.5 cd/A at 100 cd/m(2), almost constant (10.1 cd/A) up to 1000 cd/m(2), indicates that Ir-F19 is a promising blue-green emitting component for white electroluminescence. |
Ashkenasy, Gonen ; Hermans, Thomas M; Otto, Sijbren ; Taylor, Annette F Systems chemistry Journal Article In: CHEMICAL SOCIETY REVIEWS, 46 (9), pp. 2543–2554, 2017, ISSN: 0306-0012. @article{ashkenasy_systems_2017, title = {Systems chemistry}, author = {Ashkenasy, Gonen and Hermans, Thomas M. and Otto, Sijbren and Taylor, Annette F.}, doi = {10.1039/c7cs00117g}, issn = {0306-0012}, year = {2017}, date = {2017-05-01}, journal = {CHEMICAL SOCIETY REVIEWS}, volume = {46}, number = {9}, pages = {2543--2554}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Harkat, Mahboubi ; Peverini, Laurie ; Cerdan, Adrien H; Dunning, Kate ; Beudez, Juline ; Martz, Adeline ; Calimet, Nicolas ; Specht, Alexandre ; Cecchini, Marco ; Chataigneau, Thierry ; Grutter, Thomas On the permeation of large organic cations through the pore of ATP-gated P2X receptors Journal Article In: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 114 (19), pp. E3786–E3795, 2017, ISSN: 0027-8424. @article{harkat_permeation_2017, title = {On the permeation of large organic cations through the pore of ATP-gated P2X receptors}, author = {Harkat, Mahboubi and Peverini, Laurie and Cerdan, Adrien H. and Dunning, Kate and Beudez, Juline and Martz, Adeline and Calimet, Nicolas and Specht, Alexandre and Cecchini, Marco and Chataigneau, Thierry and Grutter, Thomas}, doi = {10.1073/pnas.1701379114}, issn = {0027-8424}, year = {2017}, date = {2017-05-01}, journal = {PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA}, volume = {114}, number = {19}, pages = {E3786--E3795}, abstract = {Pore dilation is thought to be a hallmark of purinergic P2X receptors. The most commonly held view of this unusual process posits that under prolonged ATP exposure the ion pore expands in a striking manner from an initial small-cation conductive state to a dilated state, which allows the passage of larger synthetic cations, such as N-methyl-D-glucamine (NMDG(+)). However, this mechanism is controversial, and the identity of the natural large permeating cations remains elusive. Here, we provide evidence that, contrary to the time-dependent pore dilation model, ATP binding opens an NMDG(+)-permeable channel within milliseconds, with a conductance that remains stable over time. We show that the time course of NMDG(+) permeability superimposes that of Na+ and demonstrate that the molecular motions leading to the permeation of NMDG(+) are very similar to those that drive Na+ flow. We found, however, that NMDG(+) “percolates” 10 times slower than Na+ in the open state, likely due to a conformational and orientational selection of permeating molecules. We further uncover that several P2X receptors, including those able to desensitize, are permeable not only to NMDG(+) but also to spermidine, a large natural cation involved in ion channel modulation, revealing a previously unrecognized P2X-mediated signaling. Altogether, our data do not support a time-dependent dilation of the pore on its own but rather reveal that the open pore of P2X receptors is wide enough to allow the permeation of large organic cations, including natural ones. This permeation mechanismhas considerable physiological significance.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Pore dilation is thought to be a hallmark of purinergic P2X receptors. The most commonly held view of this unusual process posits that under prolonged ATP exposure the ion pore expands in a striking manner from an initial small-cation conductive state to a dilated state, which allows the passage of larger synthetic cations, such as N-methyl-D-glucamine (NMDG(+)). However, this mechanism is controversial, and the identity of the natural large permeating cations remains elusive. Here, we provide evidence that, contrary to the time-dependent pore dilation model, ATP binding opens an NMDG(+)-permeable channel within milliseconds, with a conductance that remains stable over time. We show that the time course of NMDG(+) permeability superimposes that of Na+ and demonstrate that the molecular motions leading to the permeation of NMDG(+) are very similar to those that drive Na+ flow. We found, however, that NMDG(+) “percolates” 10 times slower than Na+ in the open state, likely due to a conformational and orientational selection of permeating molecules. We further uncover that several P2X receptors, including those able to desensitize, are permeable not only to NMDG(+) but also to spermidine, a large natural cation involved in ion channel modulation, revealing a previously unrecognized P2X-mediated signaling. Altogether, our data do not support a time-dependent dilation of the pore on its own but rather reveal that the open pore of P2X receptors is wide enough to allow the permeation of large organic cations, including natural ones. This permeation mechanismhas considerable physiological significance. |
Bertolazzi, Simone ; Bonacchi, Sara ; Nan, Guangjun ; Pershin, Anton ; Beljonne, David ; Samori, Paolo Engineering Chemically Active Defects in Monolayer MoS2 Transistors via Ion-Beam Irradiation and Their Healing via Vapor Deposition of Alkanethiols Journal Article In: ADVANCED MATERIALS, 29 (18), 2017, ISSN: 0935-9648. @article{bertolazzi_engineering_2017, title = {Engineering Chemically Active Defects in Monolayer MoS2 Transistors via Ion-Beam Irradiation and Their Healing via Vapor Deposition of Alkanethiols}, author = {Bertolazzi, Simone and Bonacchi, Sara and Nan, Guangjun and Pershin, Anton and Beljonne, David and Samori, Paolo}, doi = {10.1002/adma.201606760}, issn = {0935-9648}, year = {2017}, date = {2017-05-01}, journal = {ADVANCED MATERIALS}, volume = {29}, number = {18}, abstract = {Irradiation of 2D sheets of transition metal dichalcogenides with ion beams has emerged as an effective approach to engineer chemically active defects in 2D materials. In this context, argon-ion bombardment has been utilized to introduce sulfur vacancies in monolayer molybdenum disulfide (MoS2). However, a detailed understanding of the effects of generated defects on the functional properties of 2D MoS2 is still lacking. In this work, the correlation between critical electronic device parameters and the density of sulfur vacancies is systematically investigated through the fabrication and characterization of back-gated monolayer MoS2 field-effect transistors (FETs) exposed to a variable fluence of low-energy argon ions. The electrical properties of pristine and ion-irradiated FETs can be largely improved/recovered by exposing the devices to vapors of short linear thiolated molecules. Such a solvent-free chemical treatment-carried out strictly under inert atmosphere-rules out secondary healing effects induced by oxygen or oxygen-containing molecules. The results provide a guideline to design monolayer MoS2 optoelectronic devices with a controlled density of sulfur vacancies, which can be further exploited to introduce ad hoc molecular functionalities by means of thiol chemistry approaches.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Irradiation of 2D sheets of transition metal dichalcogenides with ion beams has emerged as an effective approach to engineer chemically active defects in 2D materials. In this context, argon-ion bombardment has been utilized to introduce sulfur vacancies in monolayer molybdenum disulfide (MoS2). However, a detailed understanding of the effects of generated defects on the functional properties of 2D MoS2 is still lacking. In this work, the correlation between critical electronic device parameters and the density of sulfur vacancies is systematically investigated through the fabrication and characterization of back-gated monolayer MoS2 field-effect transistors (FETs) exposed to a variable fluence of low-energy argon ions. The electrical properties of pristine and ion-irradiated FETs can be largely improved/recovered by exposing the devices to vapors of short linear thiolated molecules. Such a solvent-free chemical treatment-carried out strictly under inert atmosphere-rules out secondary healing effects induced by oxygen or oxygen-containing molecules. The results provide a guideline to design monolayer MoS2 optoelectronic devices with a controlled density of sulfur vacancies, which can be further exploited to introduce ad hoc molecular functionalities by means of thiol chemistry approaches. |
Lehn, Jean-Marie Supramolecular chemistry: Where from? Where to? Journal Article In: CHEMICAL SOCIETY REVIEWS, 46 (9), pp. 2378–2379, 2017, ISSN: 0306-0012. @article{lehn_supramolecular_2017, title = {Supramolecular chemistry: Where from? Where to?}, author = {Lehn, Jean-Marie}, doi = {10.1039/c7cs00115k}, issn = {0306-0012}, year = {2017}, date = {2017-05-01}, journal = {CHEMICAL SOCIETY REVIEWS}, volume = {46}, number = {9}, pages = {2378--2379}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Carrara, Serena ; Arcudi, Francesca ; Prato, Maurizio ; De Cola, Luisa Amine-Rich Nitrogen-Doped Carbon Nanodots as a Platform for Self-Enhancing Electrochemiluminescence Journal Article In: ANGEWANDTE CHEMIE-INTERNATIONAL EDITION, 56 (17), pp. 4757–4761, 2017, ISSN: 1433-7851. @article{carrara_amine-rich_2017, title = {Amine-Rich Nitrogen-Doped Carbon Nanodots as a Platform for Self-Enhancing Electrochemiluminescence}, author = {Carrara, Serena and Arcudi, Francesca and Prato, Maurizio and De Cola, Luisa}, doi = {10.1002/anie.201611879}, issn = {1433-7851}, year = {2017}, date = {2017-04-01}, journal = {ANGEWANDTE CHEMIE-INTERNATIONAL EDITION}, volume = {56}, number = {17}, pages = {4757--4761}, abstract = {Amine-rich nitrogen-doped carbon nanodots (NCNDs) have been successfully used as co-reactant in electrochemiluminescence (ECL) processes. Primary or tertiary amino groups on NCNDs have been studied as co-reactant sites for Ru(bpy)(3)(2+) ECL, showing their eligibility as powerful alternatives to tripropylamine (TPrA). We also report the synthesis and ECL behavior of a new covalently linked hybrid of NCNDs and Ru(bpy)(3)(2+). Notably, the NCNDs in the hybrid act both as carrier for ECL labels and as co-reactant for ECL generation. As a result, the hybrid shows a higher ECL emission as compared to the combination of the individual components, suggesting the self-enhancing ECL of the ruthenium complex due to an intramolecular electron transfer process.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Amine-rich nitrogen-doped carbon nanodots (NCNDs) have been successfully used as co-reactant in electrochemiluminescence (ECL) processes. Primary or tertiary amino groups on NCNDs have been studied as co-reactant sites for Ru(bpy)(3)(2+) ECL, showing their eligibility as powerful alternatives to tripropylamine (TPrA). We also report the synthesis and ECL behavior of a new covalently linked hybrid of NCNDs and Ru(bpy)(3)(2+). Notably, the NCNDs in the hybrid act both as carrier for ECL labels and as co-reactant for ECL generation. As a result, the hybrid shows a higher ECL emission as compared to the combination of the individual components, suggesting the self-enhancing ECL of the ruthenium complex due to an intramolecular electron transfer process. |
De Cola, Luisa ; Schuhmann, Wolfgang Biofest: Bioinspired Chemistry, Biomaterials and Bioelectrochemistry Journal Article In: CHEMPLUSCHEM, 82 (4, SI), pp. 511–512, 2017, ISSN: 2192-6506. @article{de_cola_biofest:_2017, title = {Biofest: Bioinspired Chemistry, Biomaterials and Bioelectrochemistry}, author = {De Cola, Luisa and Schuhmann, Wolfgang}, doi = {10.1002/cplu.201700109}, issn = {2192-6506}, year = {2017}, date = {2017-04-01}, journal = {CHEMPLUSCHEM}, volume = {82}, number = {4, SI}, pages = {511--512}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Hsu, Chien-Wei ; Septiadi, Dedy ; Lai, Chian-Hui ; Chen, Pengkun ; Seeberger, Peter H; De Cola, Luisa Glucose-Modified Silicon Nanoparticles for Cellular Imaging Journal Article In: CHEMPLUSCHEM, 82 (4, SI), pp. 660–667, 2017, ISSN: 2192-6506. @article{hsu_glucose-modified_2017, title = {Glucose-Modified Silicon Nanoparticles for Cellular Imaging}, author = {Hsu, Chien-Wei and Septiadi, Dedy and Lai, Chian-Hui and Chen, Pengkun and Seeberger, Peter H. and De Cola, Luisa}, doi = {10.1002/cplu.201700054}, issn = {2192-6506}, year = {2017}, date = {2017-04-01}, journal = {CHEMPLUSCHEM}, volume = {82}, number = {4, SI}, pages = {660--667}, abstract = {Luminescent silicon nanoparticles have recently attracted attention due to their remarkable stability, covalent functionalisation and tunable photoemission properties. Owing to their biocompatibility, low toxicity, and the small particle size that can be achieved by different synthetic approaches, these nanomaterials are candidates as cellular probes in the field of bioimaging, and potentially for in vivo applications. Tailoring the surface of the particles with active biomolecules such as sugar moieties can be an interesting strategy to increase the kinetics of internalisation or to vary the localisation of nanosystems in living cells. In this study, we synthesised and modified ultrasmall silicon nanoparticles with glucose covalently linked on their surface. Moreover, by varying the ratio between the amount of silicon nanoparticles and the saccharide groups, the amount of glucose, as a capping moiety, can be well controlled. FTIR spectroscopy, NMR spectroscopy, zeta potential measurements and anisotropy decay analysis confirmed the covalent binding of glucose to the nanoparticles. The photophysical behaviour of the surface-functionalised silicon quantum dots was not significantly different to that of the unmodified nanoparticles. In vitro studies demonstrated faster internalisation of the glucose-functionalised nanoparticles into HeLa cells. Different localisation and uptake kinetics of the glucose-modified particles compared to the unmodified particles are discussed in order to reveal the role played by the sugar molecules.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Luminescent silicon nanoparticles have recently attracted attention due to their remarkable stability, covalent functionalisation and tunable photoemission properties. Owing to their biocompatibility, low toxicity, and the small particle size that can be achieved by different synthetic approaches, these nanomaterials are candidates as cellular probes in the field of bioimaging, and potentially for in vivo applications. Tailoring the surface of the particles with active biomolecules such as sugar moieties can be an interesting strategy to increase the kinetics of internalisation or to vary the localisation of nanosystems in living cells. In this study, we synthesised and modified ultrasmall silicon nanoparticles with glucose covalently linked on their surface. Moreover, by varying the ratio between the amount of silicon nanoparticles and the saccharide groups, the amount of glucose, as a capping moiety, can be well controlled. FTIR spectroscopy, NMR spectroscopy, zeta potential measurements and anisotropy decay analysis confirmed the covalent binding of glucose to the nanoparticles. The photophysical behaviour of the surface-functionalised silicon quantum dots was not significantly different to that of the unmodified nanoparticles. In vitro studies demonstrated faster internalisation of the glucose-functionalised nanoparticles into HeLa cells. Different localisation and uptake kinetics of the glucose-modified particles compared to the unmodified particles are discussed in order to reveal the role played by the sugar molecules. |
Musumeci, Chiara ; Walesa-Chorab, Monika ; Gorczynski, Adam ; Markiewicz, Grzegorz ; Bogucki, Andrzej ; Swietlik, Roman ; Hnatejko, Zbigniew ; Jankowski, Wojciech ; Hoffmann, Marcin ; Orgiu, Emanuele ; Stefankiewicz, Artur R; Patroniak, Violetta ; Ciesielski, Artur ; Samori, Paolo Generation of Low-Dimensional Architectures through the Self-Assembly of Pyromellitic Diimide Derivatives Journal Article In: ACS OMEGA, 2 (4), pp. 1672–1678, 2017, ISSN: 2470-1343. @article{musumeci_generation_2017, title = {Generation of Low-Dimensional Architectures through the Self-Assembly of Pyromellitic Diimide Derivatives}, author = {Musumeci, Chiara and Walesa-Chorab, Monika and Gorczynski, Adam and Markiewicz, Grzegorz and Bogucki, Andrzej and Swietlik, Roman and Hnatejko, Zbigniew and Jankowski, Wojciech and Hoffmann, Marcin and Orgiu, Emanuele and Stefankiewicz, Artur R. and Patroniak, Violetta and Ciesielski, Artur and Samori, Paolo}, doi = {10.1021/acsomega.7b00286}, issn = {2470-1343}, year = {2017}, date = {2017-04-01}, journal = {ACS OMEGA}, volume = {2}, number = {4}, pages = {1672--1678}, abstract = {Small pi-conjugated molecules can be designed and synthesized to undergo controlled self-assembly forming low-dimensional architectures, with programmed order at the supramolecular level. Such order is of paramount importance because it defines the property of the obtained material. Here, we have focused our attention to four pyromellitic diimide derivatives exposing different types of side chains. The joint effect of different noncovalent interactions including p-p stacking, H-bonding, and van der Waals forces on the four derivatives yielded different self-assembled architectures. Atomic force microscopy studies, corroborated with infrared and nuclear magnetic resonance spectroscopic measurements, provided complementary multiscale insight into these assemblies.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Small pi-conjugated molecules can be designed and synthesized to undergo controlled self-assembly forming low-dimensional architectures, with programmed order at the supramolecular level. Such order is of paramount importance because it defines the property of the obtained material. Here, we have focused our attention to four pyromellitic diimide derivatives exposing different types of side chains. The joint effect of different noncovalent interactions including p-p stacking, H-bonding, and van der Waals forces on the four derivatives yielded different self-assembled architectures. Atomic force microscopy studies, corroborated with infrared and nuclear magnetic resonance spectroscopic measurements, provided complementary multiscale insight into these assemblies. |
Vukovic, Vuk D; Richmond, Edward ; Wolf, Elena ; Moran, Joseph Catalytic Friedel-Crafts Reactions of Highly Electronically Deactivated Benzylic Alcohols Journal Article In: ANGEWANDTE CHEMIE-INTERNATIONAL EDITION, 56 (11), pp. 3085–3089, 2017, ISSN: 1433-7851. @article{vukovic_catalytic_2017, title = {Catalytic Friedel-Crafts Reactions of Highly Electronically Deactivated Benzylic Alcohols}, author = {Vukovic, Vuk D. and Richmond, Edward and Wolf, Elena and Moran, Joseph}, doi = {10.1002/anie.201612573}, issn = {1433-7851}, year = {2017}, date = {2017-03-01}, journal = {ANGEWANDTE CHEMIE-INTERNATIONAL EDITION}, volume = {56}, number = {11}, pages = {3085--3089}, abstract = {Highly electronically deactivated benzylic alcohols, including those with a CF3 group adjacent to the OH-bearing carbon, undergo dehydrative Friedel-Crafts reactions upon exposure to catalytic Bronsted acid in 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP) solvent. Titration and kinetic experiments support the involvement of higher order solvent/acid clusters in catalysis.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Highly electronically deactivated benzylic alcohols, including those with a CF3 group adjacent to the OH-bearing carbon, undergo dehydrative Friedel-Crafts reactions upon exposure to catalytic Bronsted acid in 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP) solvent. Titration and kinetic experiments support the involvement of higher order solvent/acid clusters in catalysis. |
Leblanc, Nicolas ; Genovese, Damiano ; De Cola, Luisa ; Powell, Annie K A platform with connections in many directions - further remarkable facets to the multifaceted methylbiquinoxen dication Journal Article In: PHYSICAL CHEMISTRY CHEMICAL PHYSICS, 19 (10), pp. 6981–6988, 2017, ISSN: 1463-9076. @article{leblanc_platform_2017, title = {A platform with connections in many directions - further remarkable facets to the multifaceted methylbiquinoxen dication}, author = {Leblanc, Nicolas and Genovese, Damiano and De Cola, Luisa and Powell, Annie K.}, doi = {10.1039/c6cp07538j}, issn = {1463-9076}, year = {2017}, date = {2017-03-01}, journal = {PHYSICAL CHEMISTRY CHEMICAL PHYSICS}, volume = {19}, number = {10}, pages = {6981--6988}, abstract = {The N,N'-dimethyl-3,3'-biquinoxalinium “methylbiquinoxen” dicationic platform is revealed to have even more fascinating possibilities than we originally thought in terms of its chemical versatility. In addition to its rich redox chemistry and coordination abilities, we have now unveiled an unexpected Lewis acid/base chemistry linked with a tuneable switching of its luminescence properties. This, amongst other things, allows for the facile fluorescent covalent labelling of hydroxyl-terminated materials. This platform provides intriguing chemical prospects realised in molecular systems such as porphyrins as well as an easy alternative functionalisation methodology to that provided by click-chemistry.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The N,N'-dimethyl-3,3'-biquinoxalinium “methylbiquinoxen” dicationic platform is revealed to have even more fascinating possibilities than we originally thought in terms of its chemical versatility. In addition to its rich redox chemistry and coordination abilities, we have now unveiled an unexpected Lewis acid/base chemistry linked with a tuneable switching of its luminescence properties. This, amongst other things, allows for the facile fluorescent covalent labelling of hydroxyl-terminated materials. This platform provides intriguing chemical prospects realised in molecular systems such as porphyrins as well as an easy alternative functionalisation methodology to that provided by click-chemistry. |
Gobbi, Marco ; Bonacchi, Sara ; Lian, Jian X; Liu, Yi ; Wang, Xiao-Ye ; Stoeckel, Marc-Antoine ; Squillaci, Marco A; D'Avino, Gabriele ; Narita, Akimitsu ; Muellen, Klaus ; Feng, Xinliang ; Olivier, Yoann ; Beljonne, David ; Samori, Paolo ; Orgiu, Emanuele Periodic potentials in hybrid van der Waals heterostructures formed by supramolecular lattices on graphene Journal Article In: NATURE COMMUNICATIONS, 8 , 2017, ISSN: 2041-1723. @article{gobbi_periodic_2017, title = {Periodic potentials in hybrid van der Waals heterostructures formed by supramolecular lattices on graphene}, author = {Gobbi, Marco and Bonacchi, Sara and Lian, Jian X. and Liu, Yi and Wang, Xiao-Ye and Stoeckel, Marc-Antoine and Squillaci, Marco A. and D'Avino, Gabriele and Narita, Akimitsu and Muellen, Klaus and Feng, Xinliang and Olivier, Yoann and Beljonne, David and Samori, Paolo and Orgiu, Emanuele}, doi = {10.1038/ncomms14767}, issn = {2041-1723}, year = {2017}, date = {2017-03-01}, journal = {NATURE COMMUNICATIONS}, volume = {8}, abstract = {The rise of 2D materials made it possible to form heterostructures held together by weak interplanar van der Waals interactions. Within such van der Waals heterostructures, the occurrence of 2D periodic potentials significantly modifies the electronic structure of single sheets within the stack, therefore modulating the material properties. However, these periodic potentials are determined by the mechanical alignment of adjacent 2D materials, which is cumbersome and time-consuming. Here we show that programmable 1D periodic potentials extending over areas exceeding 10(4) nm(2) and stable at ambient conditions arise when graphene is covered by a self-assembled supramolecular lattice. The amplitude and sign of the potential can be modified without altering its periodicity by employing photoreactive molecules or their reaction products. In this regard, the supramolecular lattice/graphene bilayer represents the hybrid analogue of fully inorganic van der Waals heterostructures, highlighting the rich prospects that molecular design offers to create ad hoc materials.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The rise of 2D materials made it possible to form heterostructures held together by weak interplanar van der Waals interactions. Within such van der Waals heterostructures, the occurrence of 2D periodic potentials significantly modifies the electronic structure of single sheets within the stack, therefore modulating the material properties. However, these periodic potentials are determined by the mechanical alignment of adjacent 2D materials, which is cumbersome and time-consuming. Here we show that programmable 1D periodic potentials extending over areas exceeding 10(4) nm(2) and stable at ambient conditions arise when graphene is covered by a self-assembled supramolecular lattice. The amplitude and sign of the potential can be modified without altering its periodicity by employing photoreactive molecules or their reaction products. In this regard, the supramolecular lattice/graphene bilayer represents the hybrid analogue of fully inorganic van der Waals heterostructures, highlighting the rich prospects that molecular design offers to create ad hoc materials. |
Zhang, Lei ; Pavlica, Egon ; Zhong, Xiaolan ; Liscio, Fabiola ; Li, Songlin ; Bratina, Gvido ; Orgiu, Emanuele ; Samori, Paolo Fast-Response Photonic Device Based on Organic-Crystal Heterojunctions Assembled into a Vertical-Yet-Open Asymmetric Architecture Journal Article In: ADVANCED MATERIALS, 29 (11), 2017, ISSN: 0935-9648. @article{zhang_fast-response_2017, title = {Fast-Response Photonic Device Based on Organic-Crystal Heterojunctions Assembled into a Vertical-Yet-Open Asymmetric Architecture}, author = {Zhang, Lei and Pavlica, Egon and Zhong, Xiaolan and Liscio, Fabiola and Li, Songlin and Bratina, Gvido and Orgiu, Emanuele and Samori, Paolo}, doi = {10.1002/adma.201605760}, issn = {0935-9648}, year = {2017}, date = {2017-03-01}, journal = {ADVANCED MATERIALS}, volume = {29}, number = {11}, abstract = {Crystalline dioctyl-3,4,9,10-perylene-dicar-b-oximide nanowires and 6,13bis(triiso-propylsilylethynyl) pentacene microplates are integrated into a verticalyet- open asymmetrical heterojunction for the realization of a high-performance organic photovoltaic detector, which shows fast photoresponse, ultrahigh signal-to-noise ratio, and high sensitivity to weak light.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Crystalline dioctyl-3,4,9,10-perylene-dicar-b-oximide nanowires and 6,13bis(triiso-propylsilylethynyl) pentacene microplates are integrated into a verticalyet- open asymmetrical heterojunction for the realization of a high-performance organic photovoltaic detector, which shows fast photoresponse, ultrahigh signal-to-noise ratio, and high sensitivity to weak light. |
Liscio, Andrea ; Kouroupis-Agalou, Konstantinos ; Kovtun, Alessandro ; Gebremedhn, Elias ; El Garah, Mohamed ; Rekab, Wassima ; Orgiu, Emanuele ; Giorgini, Loris ; Samori, Paolo ; Beljonne, David ; Palermo, Vincenzo Exfoliation of Few-Layer Graphene in Volatile Solvents Using Aromatic Perylene Diimide Derivatives as Surfactants Journal Article In: CHEMPLUSCHEM, 82 (3), pp. 358–367, 2017, ISSN: 2192-6506. @article{liscio_exfoliation_2017, title = {Exfoliation of Few-Layer Graphene in Volatile Solvents Using Aromatic Perylene Diimide Derivatives as Surfactants}, author = {Liscio, Andrea and Kouroupis-Agalou, Konstantinos and Kovtun, Alessandro and Gebremedhn, Elias and El Garah, Mohamed and Rekab, Wassima and Orgiu, Emanuele and Giorgini, Loris and Samori, Paolo and Beljonne, David and Palermo, Vincenzo}, doi = {10.1002/cplu.201600503}, issn = {2192-6506}, year = {2017}, date = {2017-03-01}, journal = {CHEMPLUSCHEM}, volume = {82}, number = {3}, pages = {358--367}, abstract = {Commercial, aromatic perylene diimide (PDI) dyes were used to exfoliate few-layer graphene nanosheets in low-boiling organic solvents such as chloroform and tetrahydrofuran. Importantly, in such solvents, graphene cannot be exfoliated in the absence of the aromatic perylene diimide (PDI) dyes. The PDIs are physisorbed onto the basal plane of the nanosheet surface, which stabilized them in solution; the aromatic core lies flat on graphene and the PDI side groups influenced the physisorption strength and molecular packing. Upon varying just a single atom in the chemical structure of the side groups, significantly different exfoliation efficiencies were observed. The graphene-PDI interaction was studied at the nanoscale by scanning tunneling microscopy and molecular dynamics, at the microscale by atomic force and electron microscopy, and at the macroscale by optical spectroscopy. Thanks to the high volatility of the chosen solvent, the nanosheets can be embedded in standard polymer composites through a simple solventinduced swelling procedure.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Commercial, aromatic perylene diimide (PDI) dyes were used to exfoliate few-layer graphene nanosheets in low-boiling organic solvents such as chloroform and tetrahydrofuran. Importantly, in such solvents, graphene cannot be exfoliated in the absence of the aromatic perylene diimide (PDI) dyes. The PDIs are physisorbed onto the basal plane of the nanosheet surface, which stabilized them in solution; the aromatic core lies flat on graphene and the PDI side groups influenced the physisorption strength and molecular packing. Upon varying just a single atom in the chemical structure of the side groups, significantly different exfoliation efficiencies were observed. The graphene-PDI interaction was studied at the nanoscale by scanning tunneling microscopy and molecular dynamics, at the microscale by atomic force and electron microscopy, and at the macroscale by optical spectroscopy. Thanks to the high volatility of the chosen solvent, the nanosheets can be embedded in standard polymer composites through a simple solventinduced swelling procedure. |
Schneider, Susanne ; Licsandru, Erol-Dan ; Kocsis, Istvan ; Gilles, Arnaud ; Dumitru, Florina ; Moulin, Emilie ; Tan, Junjun ; Lehn, Jean-Marie ; Giuseppone, Nicolas ; Barboiu, Mihail Columnar Self-Assemblies of Triarylamines as Scaffolds for Artificial Biomimetic Channels for Ion and for Water Transport Journal Article In: JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 139 (10), pp. 3721–3727, 2017, ISSN: 0002-7863. @article{schneider_columnar_2017, title = {Columnar Self-Assemblies of Triarylamines as Scaffolds for Artificial Biomimetic Channels for Ion and for Water Transport}, author = {Schneider, Susanne and Licsandru, Erol-Dan and Kocsis, Istvan and Gilles, Arnaud and Dumitru, Florina and Moulin, Emilie and Tan, Junjun and Lehn, Jean-Marie and Giuseppone, Nicolas and Barboiu, Mihail}, doi = {10.1021/jacs.6b12094}, issn = {0002-7863}, year = {2017}, date = {2017-03-01}, journal = {JOURNAL OF THE AMERICAN CHEMICAL SOCIETY}, volume = {139}, number = {10}, pages = {3721--3727}, abstract = {Triarylamine molecules appended with crown-ethers or carboxylic moieties form self-assembled supramolecular channels within lipid bilayers. Fluorescence assays and voltage clamp studies reveal that the self-assemblies incorporating the crown ethers work as single channels for the selective transport of K+ or Rb+. The X-ray crystallographic structures confirm the mutual columnar self-assembly of triarylamines and crown-ethers. The dimensional fit of K+ cations within the 18-crown-6 leads to a partial dehydration and to the formation of alternating K+ cation-water wires within the channel. This original type of organization may be regarded as a biomimetic alternative of columnar K+-water wires observed for the natural KcsA channel. Supramolecular columnar arrangement was also shown for the triarylamine-carboxylic acid conjugate. In this latter case, stopped-flow light scattering analysis reveals the transport of water across lipid bilayer membranes with a relative water permeability as high as 17 mu m s(-1).}, keywords = {}, pubstate = {published}, tppubtype = {article} } Triarylamine molecules appended with crown-ethers or carboxylic moieties form self-assembled supramolecular channels within lipid bilayers. Fluorescence assays and voltage clamp studies reveal that the self-assemblies incorporating the crown ethers work as single channels for the selective transport of K+ or Rb+. The X-ray crystallographic structures confirm the mutual columnar self-assembly of triarylamines and crown-ethers. The dimensional fit of K+ cations within the 18-crown-6 leads to a partial dehydration and to the formation of alternating K+ cation-water wires within the channel. This original type of organization may be regarded as a biomimetic alternative of columnar K+-water wires observed for the natural KcsA channel. Supramolecular columnar arrangement was also shown for the triarylamine-carboxylic acid conjugate. In this latter case, stopped-flow light scattering analysis reveals the transport of water across lipid bilayer membranes with a relative water permeability as high as 17 mu m s(-1). |
Bulois, Michael ; Lehn, Christian ; Lehn, Manfred ; Terpereau, Ronan Towards a symplectic version of the Chevalley restriction theorem Journal Article In: COMPOSITIO MATHEMATICA, 153 (3), pp. 647–666, 2017, ISSN: 0010-437X. @article{bulois_towards_2017, title = {Towards a symplectic version of the Chevalley restriction theorem}, author = {Bulois, Michael and Lehn, Christian and Lehn, Manfred and Terpereau, Ronan}, doi = {10.1112/S0010437X16008277}, issn = {0010-437X}, year = {2017}, date = {2017-03-01}, journal = {COMPOSITIO MATHEMATICA}, volume = {153}, number = {3}, pages = {647--666}, abstract = {If (G, V) is a polar representation with Cartan subspace c and Weyl group W, it is shown that there is a natural morphism of Poisson schemes c circle plus c* / W -textbackslashtextbackslashtextgreater V circle plus V */// G. This morphism is conjectured to be an isomorphism of the underlying reduced varieties if (G, V) is visible. The conjecture is proved for visible stable locally free polar representations and some other examples.}, keywords = {}, pubstate = {published}, tppubtype = {article} } If (G, V) is a polar representation with Cartan subspace c and Weyl group W, it is shown that there is a natural morphism of Poisson schemes c circle plus c* / W -textbackslashtextbackslashtextgreater V circle plus V */// G. This morphism is conjectured to be an isomorphism of the underlying reduced varieties if (G, V) is visible. The conjecture is proved for visible stable locally free polar representations and some other examples. |
Dhers, Sebastien ; Holub, Jan ; Lehn, Jean-Marie Coevolution and ratiometric behaviour in metal cation-driven dynamic covalent systems Journal Article In: CHEMICAL SCIENCE, 8 (3), pp. 2125–2130, 2017, ISSN: 2041-6520. @article{dhers_coevolution_2017, title = {Coevolution and ratiometric behaviour in metal cation-driven dynamic covalent systems}, author = {Dhers, Sebastien and Holub, Jan and Lehn, Jean-Marie}, doi = {10.1039/c6sc04662b}, issn = {2041-6520}, year = {2017}, date = {2017-03-01}, journal = {CHEMICAL SCIENCE}, volume = {8}, number = {3}, pages = {2125--2130}, abstract = {Dynamic Covalent Libraries (DCLs) have been used to demonstrate coevolution behaviour on a molecular level using dynamic covalent molecules such as imines and hydrazones. Two systems are presented: the first system is based on a dialdehyde and two diamines in combination with Zn(II) and Hg(II) to form a 2 x 2 Constitutional Dynamic Network (CDN) of four complexes of macrocyclic bis-imines. Whereas the two metal ions, when reacted separately form a complex with each macrocycle with low selectivity, when applied together, each cation yields selectively a complex with one of the two macrocycles. Thus, the simultaneous application of both cations, where one might have expected the formation of four different complexes, results in the synergistic evolution (co-evolution) towards a simpler, more selective outcome under agonist amplification. The second system of 4 components, 2 amines and 2 aldehydes displays metalloselection together with a correlated evolution in distribution on complexation of Zn(II) and Cu(I) with the dynamic ligand constituents and exhibits a dynamic ratiometry process related to the antagonistic behaviour of a pair of ligand constituents.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Dynamic Covalent Libraries (DCLs) have been used to demonstrate coevolution behaviour on a molecular level using dynamic covalent molecules such as imines and hydrazones. Two systems are presented: the first system is based on a dialdehyde and two diamines in combination with Zn(II) and Hg(II) to form a 2 x 2 Constitutional Dynamic Network (CDN) of four complexes of macrocyclic bis-imines. Whereas the two metal ions, when reacted separately form a complex with each macrocycle with low selectivity, when applied together, each cation yields selectively a complex with one of the two macrocycles. Thus, the simultaneous application of both cations, where one might have expected the formation of four different complexes, results in the synergistic evolution (co-evolution) towards a simpler, more selective outcome under agonist amplification. The second system of 4 components, 2 amines and 2 aldehydes displays metalloselection together with a correlated evolution in distribution on complexation of Zn(II) and Cu(I) with the dynamic ligand constituents and exhibits a dynamic ratiometry process related to the antagonistic behaviour of a pair of ligand constituents. |
Diaz-Mendez, Rogelio ; Mezzacapo, Fabio ; Lechner, Wolfgang ; Cinti, Fabio ; Babaev, Egor ; Pupillo, Guido Glass Transitions in Monodisperse Cluster-Forming Ensembles: Vortex Matter in Type-1.5 Superconductors Journal Article In: PHYSICAL REVIEW LETTERS, 118 (6), 2017, ISSN: 0031-9007. @article{diaz-mendez_glass_2017, title = {Glass Transitions in Monodisperse Cluster-Forming Ensembles: Vortex Matter in Type-1.5 Superconductors}, author = {Diaz-Mendez, Rogelio and Mezzacapo, Fabio and Lechner, Wolfgang and Cinti, Fabio and Babaev, Egor and Pupillo, Guido}, doi = {10.1103/PhysRevLett.118.067001}, issn = {0031-9007}, year = {2017}, date = {2017-02-01}, journal = {PHYSICAL REVIEW LETTERS}, volume = {118}, number = {6}, abstract = {At low enough temperatures and high densities, the equilibrium configuration of an ensemble of ultrasoft particles is a self-assembled, ordered, cluster crystal. In the present Letter, we explore the out-of-equilibrium dynamics for a two-dimensional realization, which is relevant to superconducting materials with multiscale intervortex forces. We find that, for small temperatures following a quench, the suppression of the thermally activated particle hopping hinders the ordering. This results in a glass transition for a monodispersed ensemble, for which we derive a microscopic explanation in terms of an “effective polydispersity” induced by multiscale interactions. This demonstrates that a vortex glass can form in clean systems of thin films of “type-1.5” superconductors. An additional setup to study this physics can be layered superconducting systems, where the shape of the effective vortex-vortex interactions can be engineered.}, keywords = {}, pubstate = {published}, tppubtype = {article} } At low enough temperatures and high densities, the equilibrium configuration of an ensemble of ultrasoft particles is a self-assembled, ordered, cluster crystal. In the present Letter, we explore the out-of-equilibrium dynamics for a two-dimensional realization, which is relevant to superconducting materials with multiscale intervortex forces. We find that, for small temperatures following a quench, the suppression of the thermally activated particle hopping hinders the ordering. This results in a glass transition for a monodispersed ensemble, for which we derive a microscopic explanation in terms of an “effective polydispersity” induced by multiscale interactions. This demonstrates that a vortex glass can form in clean systems of thin films of “type-1.5” superconductors. An additional setup to study this physics can be layered superconducting systems, where the shape of the effective vortex-vortex interactions can be engineered. |
Palmioli, Alessandro ; Aliprandi, Alessandro ; Septiadi, Dedy ; Mauro, Matteo ; Bernardi, Anna ; De Cola, Luisa ; Panigati, Monica Glyco-functionalized dinuclear rhenium(I) complexes for cell imaging Journal Article In: ORGANIC & BIOMOLECULAR CHEMISTRY, 15 (7), pp. 1686–1699, 2017, ISSN: 1477-0520. @article{palmioli_glyco-functionalized_2017, title = {Glyco-functionalized dinuclear rhenium(I) complexes for cell imaging}, author = {Palmioli, Alessandro and Aliprandi, Alessandro and Septiadi, Dedy and Mauro, Matteo and Bernardi, Anna and De Cola, Luisa and Panigati, Monica}, doi = {10.1039/c6ob02559e}, issn = {1477-0520}, year = {2017}, date = {2017-02-01}, journal = {ORGANIC & BIOMOLECULAR CHEMISTRY}, volume = {15}, number = {7}, pages = {1686--1699}, abstract = {The design, synthesis and photophysical characterization of four new luminescent glycosylated luminophores based on dinuclear rhenium complexes, namely Glyco-Re, are described. The derivatives have the general formula [Re-2(mu-Cl)(2)(CO)(6)(mu-pydz-R)] (R-pydz = functionalized 1,2-pyridazine), where a sugar residue (R) is covalently bound to the pyridazine ligand in the beta position. Different synthetic pathways have been investigated including the so-called neo-glycorandomization procedure, affording stereoselectively glyco-conjugates containing glucose and maltose in a beta anomeric configuration. A multivalent dinuclear rhenium glycodendron bearing three glucose units is also synthesized. All the Glyco-Re conjugates are comprehensively characterized and their photophysical properties and cellular internalization experiments on human cervical adenocarcinoma (HeLa) cells are reported. The results show that such Glyco-Re complexes display interesting bio-imaging properties, i.e. high cell permeability, organelle selectivity, low cytotoxicity and fast internalization. These findings make the presented Glyco-Re derivatives efficient phosphorescent probes suitable for cell imaging application.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The design, synthesis and photophysical characterization of four new luminescent glycosylated luminophores based on dinuclear rhenium complexes, namely Glyco-Re, are described. The derivatives have the general formula [Re-2(mu-Cl)(2)(CO)(6)(mu-pydz-R)] (R-pydz = functionalized 1,2-pyridazine), where a sugar residue (R) is covalently bound to the pyridazine ligand in the beta position. Different synthetic pathways have been investigated including the so-called neo-glycorandomization procedure, affording stereoselectively glyco-conjugates containing glucose and maltose in a beta anomeric configuration. A multivalent dinuclear rhenium glycodendron bearing three glucose units is also synthesized. All the Glyco-Re conjugates are comprehensively characterized and their photophysical properties and cellular internalization experiments on human cervical adenocarcinoma (HeLa) cells are reported. The results show that such Glyco-Re complexes display interesting bio-imaging properties, i.e. high cell permeability, organelle selectivity, low cytotoxicity and fast internalization. These findings make the presented Glyco-Re derivatives efficient phosphorescent probes suitable for cell imaging application. |
Sinn, Stephan ; Biedermann, Frank ; De Cola, Luisa Platinum Complex Assemblies as Luminescent Probes and Tags for Drugs and Toxins in Water Journal Article In: CHEMISTRY-A EUROPEAN JOURNAL, 23 (8), pp. 1965–1971, 2017, ISSN: 0947-6539. @article{sinn_platinum_2017, title = {Platinum Complex Assemblies as Luminescent Probes and Tags for Drugs and Toxins in Water}, author = {Sinn, Stephan and Biedermann, Frank and De Cola, Luisa}, doi = {10.1002/chem.201605169}, issn = {0947-6539}, year = {2017}, date = {2017-02-01}, journal = {CHEMISTRY-A EUROPEAN JOURNAL}, volume = {23}, number = {8}, pages = {1965--1971}, abstract = {A reactive phosphorescent probe for aza-heterocyclic drugs and toxins was developed, affording a supramolecular emission-switch-on chemosensor in water. Complex formation of the heterocycles with a platinum(II) precursor proceeds readily at ambient conditions, allowing for facile analyte screening. Fifty-two structurally diverse compounds were tested, out of which 23 pyridines, imidazoles, and triazoles formed strongly emissive complex aggregates. Importantly, they all can be clearly distinguished from each other through a principal component analysis, but often also by simple visual inspection, for example, by their emission color differences (large shifts from blue to red). Also, kinetic reaction profiles and time-resolved emission features can provide valuable information for analyte distinction. The PtII complexes can be applied as emissive labels for drugs and biomolecules, owing to their advantageous photophysical properties and chemical stability in biological media such as blood.}, keywords = {}, pubstate = {published}, tppubtype = {article} } A reactive phosphorescent probe for aza-heterocyclic drugs and toxins was developed, affording a supramolecular emission-switch-on chemosensor in water. Complex formation of the heterocycles with a platinum(II) precursor proceeds readily at ambient conditions, allowing for facile analyte screening. Fifty-two structurally diverse compounds were tested, out of which 23 pyridines, imidazoles, and triazoles formed strongly emissive complex aggregates. Importantly, they all can be clearly distinguished from each other through a principal component analysis, but often also by simple visual inspection, for example, by their emission color differences (large shifts from blue to red). Also, kinetic reaction profiles and time-resolved emission features can provide valuable information for analyte distinction. The PtII complexes can be applied as emissive labels for drugs and biomolecules, owing to their advantageous photophysical properties and chemical stability in biological media such as blood. |
Bonacchi, Sara ; Gobbi, Marco ; Ferlauto, Laura ; Stoeckel, Marc-Antoine ; Liscio, Fabiola ; Milita, Silvia ; Orgiu, Emanuele ; Samori, Paolo High, Anisotropic, and Substrate-Independent Mobility in Polymer Field-Effect Transistors Based on Preassembled Semiconducting Nanofibrils Journal Article In: ACS NANO, 11 (2), pp. 2000–2007, 2017, ISSN: 1936-0851. @article{bonacchi_high_2017, title = {High, Anisotropic, and Substrate-Independent Mobility in Polymer Field-Effect Transistors Based on Preassembled Semiconducting Nanofibrils}, author = {Bonacchi, Sara and Gobbi, Marco and Ferlauto, Laura and Stoeckel, Marc-Antoine and Liscio, Fabiola and Milita, Silvia and Orgiu, Emanuele and Samori, Paolo}, doi = {10.1021/acsnano.6b08184}, issn = {1936-0851}, year = {2017}, date = {2017-02-01}, journal = {ACS NANO}, volume = {11}, number = {2}, pages = {2000--2007}, abstract = {Achieving nanoscale control over the crystalline structure and morphology of electroactive polymer films and the possibility to transfer them onto any solid substrate are important tasks for the fabrication of highperformance organic/polymeric field-effect transistors (FETs). In this work, we demonstrate that ultrathin active layers preassembled at the water/air interface can possess high, anisotropic, and substrate-independent mobility in polymer FETs. By exploiting a modified approach to the Langmuir-Schaeffer technique, we self-assemble conjugated polymers in fibrillar structures possessing controlled thickness, nanoscale structure, and morphology; these highly ordered nanofibrils can be transferred unaltered onto any arbitrary substrate. We show that FETs based on these films possess high and anisotropic hole mobility approaching 1 cm(2) V-1 s(-1) along the nanofibrils, being over 1 order of magnitude beyond the state-of-the-art for Langmuir-Schaefer polymer FETs. Significantly, we demonstrate that the FET performances are independent of the chemical nature and dielectric permittivity of the substrate, overcoming a critical limit in the field of polymer FETs. Our method allows the fabrication of ultrathin films for low-cost, high-performance, transparent, and flexible devices supported on any dielectric substrate.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Achieving nanoscale control over the crystalline structure and morphology of electroactive polymer films and the possibility to transfer them onto any solid substrate are important tasks for the fabrication of highperformance organic/polymeric field-effect transistors (FETs). In this work, we demonstrate that ultrathin active layers preassembled at the water/air interface can possess high, anisotropic, and substrate-independent mobility in polymer FETs. By exploiting a modified approach to the Langmuir-Schaeffer technique, we self-assemble conjugated polymers in fibrillar structures possessing controlled thickness, nanoscale structure, and morphology; these highly ordered nanofibrils can be transferred unaltered onto any arbitrary substrate. We show that FETs based on these films possess high and anisotropic hole mobility approaching 1 cm(2) V-1 s(-1) along the nanofibrils, being over 1 order of magnitude beyond the state-of-the-art for Langmuir-Schaefer polymer FETs. Significantly, we demonstrate that the FET performances are independent of the chemical nature and dielectric permittivity of the substrate, overcoming a critical limit in the field of polymer FETs. Our method allows the fabrication of ultrathin films for low-cost, high-performance, transparent, and flexible devices supported on any dielectric substrate. |
Men, Guangwen ; Lehn, Jean-Marie Higher Order Constitutional Dynamic Networks: [2x3] and [3x3] Networks Displaying Multiple, Synergistic and Competitive Hierarchical Adaptation Journal Article In: JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 139 (6), pp. 2474–2483, 2017, ISSN: 0002-7863. @article{men_higher_2017, title = {Higher Order Constitutional Dynamic Networks: [2x3] and [3x3] Networks Displaying Multiple, Synergistic and Competitive Hierarchical Adaptation}, author = {Men, Guangwen and Lehn, Jean-Marie}, doi = {10.1021/jacs.6b13072}, issn = {0002-7863}, year = {2017}, date = {2017-02-01}, journal = {JOURNAL OF THE AMERICAN CHEMICAL SOCIETY}, volume = {139}, number = {6}, pages = {2474--2483}, abstract = {The present study investigates the constitutional dynamic networks (CDNs) underlying dynamic covalent libraries (DCLs) that extend beyond the [2x2] case toward higher orders, namely [2x3] and [3x3] CDNs involving respectively six and nine constituents generated from the recombination of five and six components linked through reversible chemical reactions. It explores the behavior of such systems under the action of one or two effectors. More specifically and for the sake of proof of principle, it makes use of DCLs involving dynamic organic ligands and analyzes their single and double adaptive response under the action of one and two metal cation effectors. Thus, interconversions within [2x3] DCLs of six constituents (hydrazone, anylhydrazone, and imine ligands) give access to the generation of [2x3] CDNs of 3D trigonal prismatic type consisting of three [2x2] subnetworks and presenting specific responses to the application of Cu+ and Zn2+ metal cation effectors, in particular double agonistic amplification. More complex [3x3] CDNs based on nine ligand constituents of imine, hydrazone, and acylhydrazone types were also designed and subjected to the application of one Or two effectors, e.g., Cu+ and Fe2+ metal cations, revealing novel types of adaptive behavior: (i) agonistic amplification between a single constituent and a full [2x2] sub-network, and (ii) agonistic amplification along a single diagonal connecting three constituents. Of special interest is also the dependence of the response of the system to hierarchical sequence of effector application, whereby initial interaction with Cu+ ions results in the destruction of the network, whereas the sequence Fe2+ followed by Cu+ yields a clean three-constituent DCL. Finally and strikingly, the present results also demonstrate that the increase in complexity of the system by introduction of an additional entity leads to a simpler output through dynamic competition between components.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The present study investigates the constitutional dynamic networks (CDNs) underlying dynamic covalent libraries (DCLs) that extend beyond the [2x2] case toward higher orders, namely [2x3] and [3x3] CDNs involving respectively six and nine constituents generated from the recombination of five and six components linked through reversible chemical reactions. It explores the behavior of such systems under the action of one or two effectors. More specifically and for the sake of proof of principle, it makes use of DCLs involving dynamic organic ligands and analyzes their single and double adaptive response under the action of one and two metal cation effectors. Thus, interconversions within [2x3] DCLs of six constituents (hydrazone, anylhydrazone, and imine ligands) give access to the generation of [2x3] CDNs of 3D trigonal prismatic type consisting of three [2x2] subnetworks and presenting specific responses to the application of Cu+ and Zn2+ metal cation effectors, in particular double agonistic amplification. More complex [3x3] CDNs based on nine ligand constituents of imine, hydrazone, and acylhydrazone types were also designed and subjected to the application of one Or two effectors, e.g., Cu+ and Fe2+ metal cations, revealing novel types of adaptive behavior: (i) agonistic amplification between a single constituent and a full [2x2] sub-network, and (ii) agonistic amplification along a single diagonal connecting three constituents. Of special interest is also the dependence of the response of the system to hierarchical sequence of effector application, whereby initial interaction with Cu+ ions results in the destruction of the network, whereas the sequence Fe2+ followed by Cu+ yields a clean three-constituent DCL. Finally and strikingly, the present results also demonstrate that the increase in complexity of the system by introduction of an additional entity leads to a simpler output through dynamic competition between components. |
Liu, Yun ; Lehn, Jean-Marie ; Hirsch, Anna K H Molecular Biodynamers: Dynamic Covalent Analogues of Biopolymers Journal Article In: ACCOUNTS OF CHEMICAL RESEARCH, 50 (2), pp. 376–386, 2017, ISSN: 0001-4842. @article{liu_molecular_2017, title = {Molecular Biodynamers: Dynamic Covalent Analogues of Biopolymers}, author = {Liu, Yun and Lehn, Jean-Marie and Hirsch, Anna K. H.}, doi = {10.1021/acs.accounts.6b00594}, issn = {0001-4842}, year = {2017}, date = {2017-02-01}, journal = {ACCOUNTS OF CHEMICAL RESEARCH}, volume = {50}, number = {2}, pages = {376--386}, abstract = {CONSPECTUS: Constitutional dynamic chemistry (CDC) features the use of reversible linkages at both molecular and supramolecular levels, including reversible covalent bonds (dynamic covalent chemistry, DCC) and noncovalent interactions (dynamic noncovalent chemistry, DNCC). Due to its inherent reversibility and stimuli-responsiveness, CDC has been widely utilized as a powerful tool for the screening of bioactive compounds, the exploitation of receptors or substrates driven by molecular recognition, and the fabrication of constitutionally dynamic materials. Implementation of CDC in biopolymer science leads to the generation of constitutionally dynamic analogues of biopolymers, biodynamers, at the molecular level (molecular biodynamers) through DCC or at the supramolecular level (supramolecular biodynamers) via DNCC. Therefore, biodynamers are prepared by reversible covalent polymerization or noncovalent polyassociation of biorelevant monomers. In particular, molecular biodynamers, biodynamers of the covalent type whose monomeric units are connected by reversible covalent bonds, are generated by reversible polymerization of bio-based monomers and can be seen as a combination of biopolymers with DCC. Owing to the reversible covalent bonds used in DCC, molecular biodynamers can undergo continuous and spontaneous constitutional modifications via incorporation/decorporation and exchange of biorelevant monomers in response to internal or external stimuli. As a result, they behave as adaptive materials with novel properties, such as self-healing, stimuli-responsiveness, and tunable mechanical and optical character. More specifically, molecular biodynamers combine the biorelevant characters (e.g., biocompatibility, biodegradability, biofunctionality) of bioactive monomers with the dynamic features of reversible covalent bonds (e.g., changeable, tunable, controllable, self-healing, and stimuli-responsive capacities), to realize synergistic properties in one system. In addition, molecular biodynamers are commonly produced in aqueous media under mild or even physiological conditions to suit their biorelated applications. In contrast to static biopolymers emphasizing structural stability and unity by using irreversible covalent bonds, molecular biodynamers are seeking relative structural adaptability and diversity through the formation of reversible covalent bonds. Based on these considerations, molecular biodynamers are capable of reorganizing their monomers, generating, identifying, and amplifying the fittest structures in response to environmental factors. Hence, molecular biodynamers have received considerable research attention over the past decades. Accordingly, the construction of molecular biodynamers through equilibrium polymerization of nucleobase-, carbohydrate- or amino-acid-based monomers can lead to the fabrication of dynamic analogues of nucleic acids (DyNAs), polysaccharides (glycodynamers), or proteins (dynamic proteoids), respectively. In this Account, we summarize recent advances in developing different types of molecular biodynamers as structural or functional biomimetics of biopolymers, including DyNAs, glycodynamers, and dynamic proteoids. We introduce how chemists utilize various reversible reactions to generate molecular biodynamers with specific sequences and well-ordered structures in aqueous medium. We also discuss and list their potential applications in various research fields, such as drug delivery, drug discovery, gene sensing, cancer diagnosis, and treatment.}, keywords = {}, pubstate = {published}, tppubtype = {article} } CONSPECTUS: Constitutional dynamic chemistry (CDC) features the use of reversible linkages at both molecular and supramolecular levels, including reversible covalent bonds (dynamic covalent chemistry, DCC) and noncovalent interactions (dynamic noncovalent chemistry, DNCC). Due to its inherent reversibility and stimuli-responsiveness, CDC has been widely utilized as a powerful tool for the screening of bioactive compounds, the exploitation of receptors or substrates driven by molecular recognition, and the fabrication of constitutionally dynamic materials. Implementation of CDC in biopolymer science leads to the generation of constitutionally dynamic analogues of biopolymers, biodynamers, at the molecular level (molecular biodynamers) through DCC or at the supramolecular level (supramolecular biodynamers) via DNCC. Therefore, biodynamers are prepared by reversible covalent polymerization or noncovalent polyassociation of biorelevant monomers. In particular, molecular biodynamers, biodynamers of the covalent type whose monomeric units are connected by reversible covalent bonds, are generated by reversible polymerization of bio-based monomers and can be seen as a combination of biopolymers with DCC. Owing to the reversible covalent bonds used in DCC, molecular biodynamers can undergo continuous and spontaneous constitutional modifications via incorporation/decorporation and exchange of biorelevant monomers in response to internal or external stimuli. As a result, they behave as adaptive materials with novel properties, such as self-healing, stimuli-responsiveness, and tunable mechanical and optical character. More specifically, molecular biodynamers combine the biorelevant characters (e.g., biocompatibility, biodegradability, biofunctionality) of bioactive monomers with the dynamic features of reversible covalent bonds (e.g., changeable, tunable, controllable, self-healing, and stimuli-responsive capacities), to realize synergistic properties in one system. In addition, molecular biodynamers are commonly produced in aqueous media under mild or even physiological conditions to suit their biorelated applications. In contrast to static biopolymers emphasizing structural stability and unity by using irreversible covalent bonds, molecular biodynamers are seeking relative structural adaptability and diversity through the formation of reversible covalent bonds. Based on these considerations, molecular biodynamers are capable of reorganizing their monomers, generating, identifying, and amplifying the fittest structures in response to environmental factors. Hence, molecular biodynamers have received considerable research attention over the past decades. Accordingly, the construction of molecular biodynamers through equilibrium polymerization of nucleobase-, carbohydrate- or amino-acid-based monomers can lead to the fabrication of dynamic analogues of nucleic acids (DyNAs), polysaccharides (glycodynamers), or proteins (dynamic proteoids), respectively. In this Account, we summarize recent advances in developing different types of molecular biodynamers as structural or functional biomimetics of biopolymers, including DyNAs, glycodynamers, and dynamic proteoids. We introduce how chemists utilize various reversible reactions to generate molecular biodynamers with specific sequences and well-ordered structures in aqueous medium. We also discuss and list their potential applications in various research fields, such as drug delivery, drug discovery, gene sensing, cancer diagnosis, and treatment. |
Dryzhakov, Marian ; Richmond, Edward ; Li, Guang ; Moran, Joseph Catalytic B(C6F5)(3)center dot Ħ2O-promoted defluorinative functionalization of tertiary aliphatic fluorides Journal Article In: JOURNAL OF FLUORINE CHEMISTRY, 193 , pp. 45–51, 2017, ISSN: 0022-1139. @article{dryzhakov_catalytic_2017, title = {Catalytic B(C6F5)(3)center dot Ħ2O-promoted defluorinative functionalization of tertiary aliphatic fluorides}, author = {Dryzhakov, Marian and Richmond, Edward and Li, Guang and Moran, Joseph}, doi = {10.1016/j.jfluchem.2016.11.005}, issn = {0022-1139}, year = {2017}, date = {2017-01-01}, journal = {JOURNAL OF FLUORINE CHEMISTRY}, volume = {193}, pages = {45--51}, abstract = {A B(C6F5)3 center dot H2O-catalyzed defluorinative functionalization of tertiary aliphatic fluorides is described that proceeds under benign reaction conditions. The synthetic utility of the method is exemplified through the fast and efficient formation of a range of products with newly installed C(sp(3)) -N, -S, -C and -O bonds. This study illustrates the broad reactivity of otherwise inert starting materials and provides a route to valuable and synthetically underrepresented products that have not been accessed previously from such fluorinated precursors. (C) 2016 Elsevier B.V. All rights reserved.}, keywords = {}, pubstate = {published}, tppubtype = {article} } A B(C6F5)3 center dot H2O-catalyzed defluorinative functionalization of tertiary aliphatic fluorides is described that proceeds under benign reaction conditions. The synthetic utility of the method is exemplified through the fast and efficient formation of a range of products with newly installed C(sp(3)) -N, -S, -C and -O bonds. This study illustrates the broad reactivity of otherwise inert starting materials and provides a route to valuable and synthetically underrepresented products that have not been accessed previously from such fluorinated precursors. (C) 2016 Elsevier B.V. All rights reserved. |
Nowak, Rene ; Prasetyanto, Eko Adi ; De Cola, Luisa ; Bojer, Beate ; Siegel, Renee ; Senker, Juergen ; Roessler, Ernst ; Weber, Birgit Proton-driven coordination-induced spin state switch (PD-CISSS) of iron(II) complexes Journal Article In: CHEMICAL COMMUNICATIONS, 53 (5), pp. 971–974, 2017, ISSN: 1359-7345. @article{nowak_proton-driven_2017, title = {Proton-driven coordination-induced spin state switch (PD-CISSS) of iron(II) complexes}, author = {Nowak, Rene and Prasetyanto, Eko Adi and De Cola, Luisa and Bojer, Beate and Siegel, Renee and Senker, Juergen and Roessler, Ernst and Weber, Birgit}, doi = {10.1039/c6cc08618g}, issn = {1359-7345}, year = {2017}, date = {2017-01-01}, journal = {CHEMICAL COMMUNICATIONS}, volume = {53}, number = {5}, pages = {971--974}, abstract = {Here we report the completely reversible spin state switch of the naturally diamagnetic tris(bipyridine) iron(II) complex and the spin crossover complex bis(2,6-bis(1H-pyrazol-3-yl) pyridine) iron(II) by the variation of the pH followed by H-1-NMR, UV-Vis spectroscopy, and magnetic and relaxivity measurements in solution and as composite materials encapsulated in a zeolite matrix.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Here we report the completely reversible spin state switch of the naturally diamagnetic tris(bipyridine) iron(II) complex and the spin crossover complex bis(2,6-bis(1H-pyrazol-3-yl) pyridine) iron(II) by the variation of the pH followed by H-1-NMR, UV-Vis spectroscopy, and magnetic and relaxivity measurements in solution and as composite materials encapsulated in a zeolite matrix. |
Atoini, Youssef ; Prasetyanto, Eko Adi ; Chen, Pengkun ; Jonckheere, Dries ; De Vos, Dirk ; De Cola, Luisa Tuning luminescent properties of a metal organic framework by insertion of metal complexes Journal Article In: SUPRAMOLECULAR CHEMISTRY, 29 (10, SI), pp. 758–767, 2017, ISSN: 1061-0278. @article{atoini_tuning_2017, title = {Tuning luminescent properties of a metal organic framework by insertion of metal complexes}, author = {Atoini, Youssef and Prasetyanto, Eko Adi and Chen, Pengkun and Jonckheere, Dries and De Vos, Dirk and De Cola, Luisa}, doi = {10.1080/10610278.2017.1290249}, issn = {1061-0278}, year = {2017}, date = {2017-01-01}, journal = {SUPRAMOLECULAR CHEMISTRY}, volume = {29}, number = {10, SI}, pages = {758--767}, abstract = {We report the preparation and characterisation of new emissive materials based on the insertion of platinum(II) and iridium(III) complexes inside the Al(OH)(bipyridine dicarboxylate) metal organic framework (MOF-253). Guest incorporation is performed by coordination of a metal complex precursor, and provides increased robustness to the system compared to guest inclusion by its physical diffusion. Powder X-ray diffraction analysis highlights the high degree of crystallinity of the materials, with a complete change in the lattice parameters upon metal complex insertion. The photophysical properties of the resulting materials were thoroughly investigated. This synthetic approach is particularly attractive since, as we show, it is possible to tune the emission maxima of our materials over the entire visible range. [GRAPHICS]}, keywords = {}, pubstate = {published}, tppubtype = {article} } We report the preparation and characterisation of new emissive materials based on the insertion of platinum(II) and iridium(III) complexes inside the Al(OH)(bipyridine dicarboxylate) metal organic framework (MOF-253). Guest incorporation is performed by coordination of a metal complex precursor, and provides increased robustness to the system compared to guest inclusion by its physical diffusion. Powder X-ray diffraction analysis highlights the high degree of crystallinity of the materials, with a complete change in the lattice parameters upon metal complex insertion. The photophysical properties of the resulting materials were thoroughly investigated. This synthetic approach is particularly attractive since, as we show, it is possible to tune the emission maxima of our materials over the entire visible range. [GRAPHICS] |
Aliprandi, Alessandro ; Moreira, Tiago ; Anichini, Cosimo ; Stoeckel, Marc-Antoine ; Eredia, Matilde ; Sassi, Ugo ; Bruna, Matteo ; Pinheiro, Carlos ; Laia, Cesar A T; Bonacchi, Sara ; Samori, Paolo Hybrid Copper-Nanowire-Reduced-Graphene-Oxide Coatings: A “Green Solution” Toward Highly Transparent, Highly Conductive, and Flexible Electrodes for (Opto)Electronics Journal Article In: ADVANCED MATERIALS, 29 (41), 2017, ISSN: 0935-9648. @article{aliprandi_hybrid_2017, title = {Hybrid Copper-Nanowire-Reduced-Graphene-Oxide Coatings: A “Green Solution” Toward Highly Transparent, Highly Conductive, and Flexible Electrodes for (Opto)Electronics}, author = {Aliprandi, Alessandro and Moreira, Tiago and Anichini, Cosimo and Stoeckel, Marc-Antoine and Eredia, Matilde and Sassi, Ugo and Bruna, Matteo and Pinheiro, Carlos and Laia, Cesar A. T. and Bonacchi, Sara and Samori, Paolo}, doi = {10.1002/adma.201703225}, issn = {0935-9648}, year = {2017}, date = {2017-01-01}, journal = {ADVANCED MATERIALS}, volume = {29}, number = {41}, abstract = {This study reports a novel green chemistry approach to assemble copper-nanowires/reduced-graphene-oxide hybrid coatings onto inorganic and organic supports. Such films are robust and combine sheet resistances (textbackslashtextbackslashtextless30 Omega sq(-1)) and transparencies in the visible region (transmittance textbackslashtextbackslashtextgreater 70%) that are rivalling those of indium-tin oxide. These electrodes are suitable for flexible electronic applications as they show a sheet resistance change of textbackslashtextbackslashtextless4% after 10 000 bending cycles at a bending radius of 1.0 cm, when supported on polyethylene terephthalate foils. Significantly, the wet-chemistry method involves the preparation of dispersions in environmentally friendly solvents and avoids the use of harmful reagents. Such inks are processed at room temperature on a wide variety of surfaces by spray coating. As a proof-of-concept, this study demonstrates the successful use of such coatings as electrodes in high-performance electrochromic devices. The robustness of the electrodes is demonstrated by performing several tens of thousands of cycles of device operation. These unique conducting coatings hold potential for being exploited as transparent electrodes in numerous optoelectronic applications such as solar cells, light-emitting diodes, and displays.}, keywords = {}, pubstate = {published}, tppubtype = {article} } This study reports a novel green chemistry approach to assemble copper-nanowires/reduced-graphene-oxide hybrid coatings onto inorganic and organic supports. Such films are robust and combine sheet resistances (textbackslashtextbackslashtextless30 Omega sq(-1)) and transparencies in the visible region (transmittance textbackslashtextbackslashtextgreater 70%) that are rivalling those of indium-tin oxide. These electrodes are suitable for flexible electronic applications as they show a sheet resistance change of textbackslashtextbackslashtextless4% after 10 000 bending cycles at a bending radius of 1.0 cm, when supported on polyethylene terephthalate foils. Significantly, the wet-chemistry method involves the preparation of dispersions in environmentally friendly solvents and avoids the use of harmful reagents. Such inks are processed at room temperature on a wide variety of surfaces by spray coating. As a proof-of-concept, this study demonstrates the successful use of such coatings as electrodes in high-performance electrochromic devices. The robustness of the electrodes is demonstrated by performing several tens of thousands of cycles of device operation. These unique conducting coatings hold potential for being exploited as transparent electrodes in numerous optoelectronic applications such as solar cells, light-emitting diodes, and displays. |
El Garah, Mohamed ; Borre, Etienne ; Ciesielski, Artur ; Dianat, Arezoo ; Gutierrez, Rafael ; Cuniberti, Gianaurelio ; Bellemin-Laponnaz, Stephane ; Mauro, Matteo ; Samori, Paolo Light-Induced Contraction/Expansion of 1D Photoswitchable Metallopolymer Monitored at the Solid-Liquid Interface Journal Article In: SMALL, 13 (40), 2017, ISSN: 1613-6810. @article{el_garah_light-induced_2017, title = {Light-Induced Contraction/Expansion of 1D Photoswitchable Metallopolymer Monitored at the Solid-Liquid Interface}, author = {El Garah, Mohamed and Borre, Etienne and Ciesielski, Artur and Dianat, Arezoo and Gutierrez, Rafael and Cuniberti, Gianaurelio and Bellemin-Laponnaz, Stephane and Mauro, Matteo and Samori, Paolo}, doi = {10.1002/smll.201701790}, issn = {1613-6810}, year = {2017}, date = {2017-01-01}, journal = {SMALL}, volume = {13}, number = {40}, abstract = {The use of a bottom-up approach to the fabrication of nanopatterned functional surfaces, which are capable to respond to external stimuli, is of great current interest. Herein, the preparation of light-responsive, linear supramolecular metallopolymers constituted by the ideally infinite repetition of a ditopic ligand bearing an azoaryl moiety and Co(II) coordination nodes is described. The supramolecular polymerization process is followed by optical spectroscopy in dimethylformamide solution. Noteworthy, a submolecularly resolved scanning tunneling microscopy (STM) study of the in situ reversible trans-to-cis photoisomerization of a photoswitchable metallopolymer that self-assembles into 2D crystalline patterns onto a highly oriented pyrolytic graphite surface is achieved for the first time. The STM analysis of the nanopatterned surfaces is corroborated by modeling the physisorbed species onto a graphene slab before and after irradiation by means of density functional theory calculation. Significantly, switching of the monolayers consisting of supramolecular Co(II) metallopolymer bearing trans-azoaryl units to a novel pattern based on cis isomers can be triggered by UV light and reversed back to the trans conformer by using visible light, thereby restoring the trans-based supramolecular 2D packing. These findings represent a step forward toward the design and preparation of photoresponsive “smart” surfaces organized with an atomic precision.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The use of a bottom-up approach to the fabrication of nanopatterned functional surfaces, which are capable to respond to external stimuli, is of great current interest. Herein, the preparation of light-responsive, linear supramolecular metallopolymers constituted by the ideally infinite repetition of a ditopic ligand bearing an azoaryl moiety and Co(II) coordination nodes is described. The supramolecular polymerization process is followed by optical spectroscopy in dimethylformamide solution. Noteworthy, a submolecularly resolved scanning tunneling microscopy (STM) study of the in situ reversible trans-to-cis photoisomerization of a photoswitchable metallopolymer that self-assembles into 2D crystalline patterns onto a highly oriented pyrolytic graphite surface is achieved for the first time. The STM analysis of the nanopatterned surfaces is corroborated by modeling the physisorbed species onto a graphene slab before and after irradiation by means of density functional theory calculation. Significantly, switching of the monolayers consisting of supramolecular Co(II) metallopolymer bearing trans-azoaryl units to a novel pattern based on cis isomers can be triggered by UV light and reversed back to the trans conformer by using visible light, thereby restoring the trans-based supramolecular 2D packing. These findings represent a step forward toward the design and preparation of photoresponsive “smart” surfaces organized with an atomic precision. |
2016 |
Richmond, Edward ; Moran, Joseph Harnessing Complex Mixtures for Catalyst Discovery Journal Article In: SYNLETT, 27 (19), pp. 2637–2643, 2016, ISSN: 0936-5214. @article{richmond_harnessing_2016, title = {Harnessing Complex Mixtures for Catalyst Discovery}, author = {Richmond, Edward and Moran, Joseph}, doi = {10.1055/s-0036-1588334}, issn = {0936-5214}, year = {2016}, date = {2016-12-01}, journal = {SYNLETT}, volume = {27}, number = {19}, pages = {2637--2643}, abstract = {To complement high-throughput experimental approaches to catalyst discovery and optimization, we have employed a simple algorithmic approach to screening and deconvoluting complex mixtures of catalyst components with the goal of rapidly identifying new catalysts and cooperative effects. This Synpacts article highlights how interplay between screening mixtures and mechanistic studies can allow users to rapidly move from initial discovery to rationally developed second-generation catalytic systems. 1 Introduction 2 Application to Lewis and BrOnsted Acid Catalysis 3 Application to Transition-Metal Catalysis 4 Conclusion and Perspective}, keywords = {}, pubstate = {published}, tppubtype = {article} } To complement high-throughput experimental approaches to catalyst discovery and optimization, we have employed a simple algorithmic approach to screening and deconvoluting complex mixtures of catalyst components with the goal of rapidly identifying new catalysts and cooperative effects. This Synpacts article highlights how interplay between screening mixtures and mechanistic studies can allow users to rapidly move from initial discovery to rationally developed second-generation catalytic systems. 1 Introduction 2 Application to Lewis and BrOnsted Acid Catalysis 3 Application to Transition-Metal Catalysis 4 Conclusion and Perspective |
Brennen, G K; Pupillo, G; Rico, E; Stace, T M; Vodola, D Loops and Strings in a Superconducting Lattice Gauge Simulator Journal Article In: PHYSICAL REVIEW LETTERS, 117 (24), 2016, ISSN: 0031-9007. @article{brennen_loops_2016, title = {Loops and Strings in a Superconducting Lattice Gauge Simulator}, author = {Brennen, G. K. and Pupillo, G. and Rico, E. and Stace, T. M. and Vodola, D.}, doi = {10.1103/PhysRevLett.117.240504}, issn = {0031-9007}, year = {2016}, date = {2016-12-01}, journal = {PHYSICAL REVIEW LETTERS}, volume = {117}, number = {24}, abstract = {We propose an architecture for an analog quantum simulator of electromagnetism in 2 + 1 dimensions, based on an array of superconducting fluxonium devices. The encoding is in the integer (spin-1) representation of the quantum link model formulation of compact U(1) lattice gauge theory. We show how to engineer Gauss' law via an ancilla mediated gadget construction, and how to tune between the strongly coupled and intermediately coupled regimes. The witnesses to the existence of the predicted confining phase of the model are provided by nonlocal order parameters from Wilson loops and disorder parameters from `t Hooft strings. We show how to construct such operators in this model and how to measure them nondestructively via dispersive coupling of the fluxonium islands to a microwave cavity mode. Numerical evidence is found for the existence of the confined phase in the ground state of the simulation Hamiltonian on a ladder geometry.}, keywords = {}, pubstate = {published}, tppubtype = {article} } We propose an architecture for an analog quantum simulator of electromagnetism in 2 + 1 dimensions, based on an array of superconducting fluxonium devices. The encoding is in the integer (spin-1) representation of the quantum link model formulation of compact U(1) lattice gauge theory. We show how to engineer Gauss' law via an ancilla mediated gadget construction, and how to tune between the strongly coupled and intermediately coupled regimes. The witnesses to the existence of the predicted confining phase of the model are provided by nonlocal order parameters from Wilson loops and disorder parameters from `t Hooft strings. We show how to construct such operators in this model and how to measure them nondestructively via dispersive coupling of the fluxonium islands to a microwave cavity mode. Numerical evidence is found for the existence of the confined phase in the ground state of the simulation Hamiltonian on a ladder geometry. |
Publications
2017 |
From Chemical Topology to Molecular Machines (Nobel Lecture) Journal Article In: ANGEWANDTE CHEMIE-INTERNATIONAL EDITION, 56 (37, SI), pp. 11080–11093, 2017, ISSN: 1433-7851. |
Self-organization of amino-acid-derived NDI assemblies into a nanofibrillar superstructure with humidity sensitive n-type semiconducting properties Journal Article In: CHEMICAL COMMUNICATIONS, 53 (70), pp. 9713–9716, 2017, ISSN: 1359-7345. |
Ultrafast dynamics of two copper bisphenanthroline complexes measured by x-ray transient absorption spectroscopy Journal Article In: JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS, 50 (15), 2017, ISSN: 0953-4075. |
Kinetic Selectivity and Thermodynamic Features of Competitive Imine Formation in Dynamic Covalent Chemistry Journal Article In: CHEMISTRY-A EUROPEAN JOURNAL, 23 (46), pp. 11108–11118, 2017, ISSN: 0947-6539. |
Pyrazolo[4,3-h]quinoline Ligand-Based Iridium(III) Complexes for Electrochemiluminescence Journal Article In: CHEMISTRY-AN ASIAN JOURNAL, 12 (13, SI), pp. 1649–1658, 2017, ISSN: 1861-4728. |
Dissecting mechanism of coupled folding and binding of an intrinsically disordered protein by chemical synthesis of conformationally constrained analogues Journal Article In: CHEMICAL COMMUNICATIONS, 53 (53), pp. 7369–7372, 2017, ISSN: 1359-7345. |
Bi-Layer textures: a Model for Synthesis and Deformation of Composite Textures Journal Article In: COMPUTER GRAPHICS FORUM, 36 (4), pp. 111–122, 2017, ISSN: 0167-7055. |
Morphology and Electronic Properties of Electrochemically Exfoliated Graphene Journal Article In: JOURNAL OF PHYSICAL CHEMISTRY LETTERS, 8 (14), pp. 3347–3355, 2017, ISSN: 1948-7185. |
Photoisomerisation and light-induced morphological switching of a polyoxometalate-azobenzene hybrid Journal Article In: CHEMICAL COMMUNICATIONS, 53 (53), pp. 7278–7281, 2017, ISSN: 1359-7345. |
Asymmetric Injection in Organic Transistors via Direct SAM Functionalization of Source and Drain Electrodes Journal Article In: ACS OMEGA, 2 (7), pp. 3502–3508, 2017, ISSN: 2470-1343. |
Energy Transfer between Spatially Separated Entangled Molecules Journal Article In: ANGEWANDTE CHEMIE-INTERNATIONAL EDITION, 56 (31), pp. 9034–9038, 2017, ISSN: 1433-7851. |
Controlling the Catalytic Functions of DNAzymes within Constitutional Dynamic Networks of DNA Nanostructures Journal Article In: JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 139 (28), pp. 9662–9671, 2017, ISSN: 0002-7863. |
Coexisting origins of subdiffusion in internal dynamics of proteins Journal Article In: PHYSICAL REVIEW E, 95 (6), 2017, ISSN: 2470-0045. |
Rapid self-healing and anion selectivity in metallosupramolecular gels assisted by fluorine-fluorine interactions Journal Article In: DALTON TRANSACTIONS, 46 (22), pp. 7309–7316, 2017, ISSN: 1477-9226. |
Stabilisation effects of phosphane ligands in the homogeneous approach of sunlight induced hydrogen production Journal Article In: FARADAY DISCUSSIONS, 198 , pp. 211–233, 2017, ISSN: 1359-6640. |
Non-equilibrium steady states in supramolecular polymerization Journal Article In: NATURE COMMUNICATIONS, 8 , 2017, ISSN: 2041-1723. |
Improving the electrical performance of solution processed oligothiophene thin-film transistors via structural similarity blending Journal Article In: JOURNAL OF MATERIALS CHEMISTRY C, 5 (21), pp. 5048–5054, 2017, ISSN: 2050-7526. |
Graphene/Polymer Nanocomposites for Supercapacitors Journal Article In: CHEMNANOMAT, 3 (6, SI), pp. 362–372, 2017, ISSN: 2199-692X. |
Ultrafast Delamination of Graphite into High-Quality Graphene Using Alternating Currents Journal Article In: ANGEWANDTE CHEMIE-INTERNATIONAL EDITION, 56 (23), pp. 6669–6675, 2017, ISSN: 1433-7851. |
Chiral Amplification by Self-Assembly of Neutral Luminescent Platinum(II) Complexes Journal Article In: CHEMISTRY-A EUROPEAN JOURNAL, 23 (25), pp. 5957–5961, 2017, ISSN: 0947-6539. |
A highly fluorinated iridium complex as a blue-green emitting component for white electroluminescence Journal Article In: SYNTHETIC METALS, 227 , pp. 148–155, 2017, ISSN: 0379-6779. |
Systems chemistry Journal Article In: CHEMICAL SOCIETY REVIEWS, 46 (9), pp. 2543–2554, 2017, ISSN: 0306-0012. |
On the permeation of large organic cations through the pore of ATP-gated P2X receptors Journal Article In: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 114 (19), pp. E3786–E3795, 2017, ISSN: 0027-8424. |
Engineering Chemically Active Defects in Monolayer MoS2 Transistors via Ion-Beam Irradiation and Their Healing via Vapor Deposition of Alkanethiols Journal Article In: ADVANCED MATERIALS, 29 (18), 2017, ISSN: 0935-9648. |
Supramolecular chemistry: Where from? Where to? Journal Article In: CHEMICAL SOCIETY REVIEWS, 46 (9), pp. 2378–2379, 2017, ISSN: 0306-0012. |
Amine-Rich Nitrogen-Doped Carbon Nanodots as a Platform for Self-Enhancing Electrochemiluminescence Journal Article In: ANGEWANDTE CHEMIE-INTERNATIONAL EDITION, 56 (17), pp. 4757–4761, 2017, ISSN: 1433-7851. |
Biofest: Bioinspired Chemistry, Biomaterials and Bioelectrochemistry Journal Article In: CHEMPLUSCHEM, 82 (4, SI), pp. 511–512, 2017, ISSN: 2192-6506. |
Glucose-Modified Silicon Nanoparticles for Cellular Imaging Journal Article In: CHEMPLUSCHEM, 82 (4, SI), pp. 660–667, 2017, ISSN: 2192-6506. |
Generation of Low-Dimensional Architectures through the Self-Assembly of Pyromellitic Diimide Derivatives Journal Article In: ACS OMEGA, 2 (4), pp. 1672–1678, 2017, ISSN: 2470-1343. |
Catalytic Friedel-Crafts Reactions of Highly Electronically Deactivated Benzylic Alcohols Journal Article In: ANGEWANDTE CHEMIE-INTERNATIONAL EDITION, 56 (11), pp. 3085–3089, 2017, ISSN: 1433-7851. |
A platform with connections in many directions - further remarkable facets to the multifaceted methylbiquinoxen dication Journal Article In: PHYSICAL CHEMISTRY CHEMICAL PHYSICS, 19 (10), pp. 6981–6988, 2017, ISSN: 1463-9076. |
Periodic potentials in hybrid van der Waals heterostructures formed by supramolecular lattices on graphene Journal Article In: NATURE COMMUNICATIONS, 8 , 2017, ISSN: 2041-1723. |
Fast-Response Photonic Device Based on Organic-Crystal Heterojunctions Assembled into a Vertical-Yet-Open Asymmetric Architecture Journal Article In: ADVANCED MATERIALS, 29 (11), 2017, ISSN: 0935-9648. |
Exfoliation of Few-Layer Graphene in Volatile Solvents Using Aromatic Perylene Diimide Derivatives as Surfactants Journal Article In: CHEMPLUSCHEM, 82 (3), pp. 358–367, 2017, ISSN: 2192-6506. |
Columnar Self-Assemblies of Triarylamines as Scaffolds for Artificial Biomimetic Channels for Ion and for Water Transport Journal Article In: JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 139 (10), pp. 3721–3727, 2017, ISSN: 0002-7863. |
Towards a symplectic version of the Chevalley restriction theorem Journal Article In: COMPOSITIO MATHEMATICA, 153 (3), pp. 647–666, 2017, ISSN: 0010-437X. |
Coevolution and ratiometric behaviour in metal cation-driven dynamic covalent systems Journal Article In: CHEMICAL SCIENCE, 8 (3), pp. 2125–2130, 2017, ISSN: 2041-6520. |
Glass Transitions in Monodisperse Cluster-Forming Ensembles: Vortex Matter in Type-1.5 Superconductors Journal Article In: PHYSICAL REVIEW LETTERS, 118 (6), 2017, ISSN: 0031-9007. |
Glyco-functionalized dinuclear rhenium(I) complexes for cell imaging Journal Article In: ORGANIC & BIOMOLECULAR CHEMISTRY, 15 (7), pp. 1686–1699, 2017, ISSN: 1477-0520. |
Platinum Complex Assemblies as Luminescent Probes and Tags for Drugs and Toxins in Water Journal Article In: CHEMISTRY-A EUROPEAN JOURNAL, 23 (8), pp. 1965–1971, 2017, ISSN: 0947-6539. |
High, Anisotropic, and Substrate-Independent Mobility in Polymer Field-Effect Transistors Based on Preassembled Semiconducting Nanofibrils Journal Article In: ACS NANO, 11 (2), pp. 2000–2007, 2017, ISSN: 1936-0851. |
Higher Order Constitutional Dynamic Networks: [2x3] and [3x3] Networks Displaying Multiple, Synergistic and Competitive Hierarchical Adaptation Journal Article In: JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 139 (6), pp. 2474–2483, 2017, ISSN: 0002-7863. |
Molecular Biodynamers: Dynamic Covalent Analogues of Biopolymers Journal Article In: ACCOUNTS OF CHEMICAL RESEARCH, 50 (2), pp. 376–386, 2017, ISSN: 0001-4842. |
Catalytic B(C6F5)(3)center dot Ħ2O-promoted defluorinative functionalization of tertiary aliphatic fluorides Journal Article In: JOURNAL OF FLUORINE CHEMISTRY, 193 , pp. 45–51, 2017, ISSN: 0022-1139. |
Proton-driven coordination-induced spin state switch (PD-CISSS) of iron(II) complexes Journal Article In: CHEMICAL COMMUNICATIONS, 53 (5), pp. 971–974, 2017, ISSN: 1359-7345. |
Tuning luminescent properties of a metal organic framework by insertion of metal complexes Journal Article In: SUPRAMOLECULAR CHEMISTRY, 29 (10, SI), pp. 758–767, 2017, ISSN: 1061-0278. |
Hybrid Copper-Nanowire-Reduced-Graphene-Oxide Coatings: A “Green Solution” Toward Highly Transparent, Highly Conductive, and Flexible Electrodes for (Opto)Electronics Journal Article In: ADVANCED MATERIALS, 29 (41), 2017, ISSN: 0935-9648. |
Light-Induced Contraction/Expansion of 1D Photoswitchable Metallopolymer Monitored at the Solid-Liquid Interface Journal Article In: SMALL, 13 (40), 2017, ISSN: 1613-6810. |
2016 |
Harnessing Complex Mixtures for Catalyst Discovery Journal Article In: SYNLETT, 27 (19), pp. 2637–2643, 2016, ISSN: 0936-5214. |
Loops and Strings in a Superconducting Lattice Gauge Simulator Journal Article In: PHYSICAL REVIEW LETTERS, 117 (24), 2016, ISSN: 0031-9007. |