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8 results on '"Grant WE"'

1. Quasilinear 3d-metal(<scp>i</scp>) complexes [KM(N(Dipp)SiR3)2] (M = Cr–Co) – structural diversity, solution state behaviour and reactivity

Author

Igor Müller, Carine Duhayon, C. Gunnar Werncke, Ruth Weller, Sébastien Bontemps, Sylviane Sabo-Etienne, Philipps University of Marburg, Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), DFG (grant WE 5627/1-1 and WE 5627/4-1), Philipps-University Marburg, CNRS, and ANR-12-BS07-0011,IRONHYC,Complexes de fer polyhydrures et catalyse d'hydrofonctionnalisation(2012)

Subjects
010405 organic chemistry, Ligand, Chemistry, chemistry.chemical_element, Disproportionation, 010402 general chemistry, Potassium Cation, 01 natural sciences, Redox, 0104 chemical sciences, Inorganic Chemistry, Metal, visual_art, Intramolecular force, Polymer chemistry, visual_art.visual_art_medium, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Reactivity (chemistry), Cobalt
Abstract

International audience; The synthesis and characterization of neutral quasilinear 3d-metal(I) complexes of chromium to cobalt of the type [KM(N(Dipp)SiMe3)2] (Dipp = 2,6-di-iso-propylphenyl) are reported. In solid state these metal(I) complexes either occur as isolated molecules (Co) or are part of a potassium ion linked 1D-coordination polymer (Cr–Fe). In solution the potassium cation is either ligated within the ligand sphere of the metal silylamide or is separated from the complex depending on the solvent. For iron, we showcase that it is possible to use sodium or lithium metal for the reduction of the metal(II) precursor. However, in these cases the resulting iron(I) complexes can only be isolated upon cation separation using an appropriate crown-ether. Further, the neutral metal(I) complexes are used to introduce NBu4+ as an organic cation in the case of cobalt and iron. The impact of the intramolecular cation complexation was further demonstrated upon reaction with diphenyl acetylene which leads to bond formation processes and redox disproportionation instead of η2-alkyne complex formation.

Published
2021
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2. Ethynylene-analogues of hemicurcuminoids: Synthesis and ground- and excited properties of their boron difluoride complexes

Author

Elena Zaborova, Miguel Ponce-Vargas, Gabriel Canard, Jean-Charles Ribierre, Eunsun Kim, Anthony D'Aléo, Boris Le Guennic, Frédéric Fages, Bogdan Štefane, Jeong Weon Wu, Franc Požgan, Denis Jacquemin, E. Y. Choi, Faculty of Chemistry and Chemical Technology, University of Ljubljana, EWHA Womans University (EWHA), Institut des Sciences Chimiques de Rennes (ISCR), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Chimie Et Interdisciplinarité : Synthèse, Analyse, Modélisation (CEISAM), Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Centre Interdisciplinaire de Nanoscience de Marseille (CINaM), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), This work has been carried out in the framework of International Associated Laboratory 'Functional nanostructures: morphology, nanoelectronics and ultrafast optics' (LIA NANOFUNC), France. ADA, E. K, E. C and JW. W. are supported by funding of the Ministry of Science, ICT & Future Planning, Korea (2015001948, 2014M3A6B3063706). D. J. acknowledges both the European Research Council for the starting grant (Marches no. 278845) and the Région des Pays de la Loire for the LUMOMAT project. We thank the CCIPL (Centre de Calcul Intensif des Pays de la Loire) and the GENCI-CINES/IDRIS for the allocation of computing time. M.P.-V. thanks the ANR (project ANR-14-CE05-0035-02) for his postdoctoral grant. We also thank the Slovenian Research Agency for the financial support through grant P1-0179. X-Ray crystal structures of 3, 4, 6 and 7 have been deposited to CCDC and are referenced as followed CCDC 1515132, CCDC 1515133, CCDC 1515134 and CCDC 1515135, respectively., Univeristy of Ljubljana, Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Université de Nantes (UN)-Université de Nantes (UN)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA), and Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU)

Subjects
[CHIM.ORGA]Chemical Sciences/Organic chemistry, Chemistry, Process Chemistry and Technology, General Chemical Engineering, Near-infrared spectroscopy, Solvatochromism, Charge (physics), 02 engineering and technology, 010402 general chemistry, 021001 nanoscience & nanotechnology, Photochemistry, Electrochemistry, 01 natural sciences, Fluorescence, 0104 chemical sciences, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, Charge transfer, Excited state, Boron difluoride, Photophyics, 0210 nano-technology, Quantum, ComputingMilieux_MISCELLANEOUS, Boron difluoride complex
Abstract

The synthesis, characterization and (TD)-DFT calculations of the electrochemical and photophysical properties of novel ethynylene-analogues of hemicurcuminoids are described. These dyes are both emissive in solution and in the solid state. While compounds that emit through an efficient charge transfer (CT) state show solvatochromic behaviour associated with low fluorescence quantum yields, those lacking of donor groups show high fluorescence quantum yields of 70–80%, in solution. The latter dyes also present the advantage to emit in the solid state in the visible region with fluorescence quantum yields up to 23%. Their condensed phase spectrum can be bathochromically shifted to the near infrared region (742 nm) by appending a strong donor group.

Published
2017
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3. Selective conversion of various monosaccharaides into sugar acids by additive‐free dehydrogenation in water

Author

Pilar Borja, Joseph P. Byrne, Cristian Vicent, Jose A. Mata, Martin Albrecht, Andres Mollar‐Cuni, and The authors thank the financial support from MICIU/AEI/FEDER (RTI2018-098237-B-C22) and Universitat Jaume I (UJI-B2018-23). P. Borja thanks the Universitat Jaume I for a postdoctoral grant. We acknowledge generous support from the European Commission for a Marie Skłodowska Curie Individual Fellowship to J. P. Byrne (Grant 749549) and from the European Research Council to M. Albrecht (CoG 615653). The authors are very grateful to the ‘Servei Central d’Instrumentació Científica (SCIC)’ of the Universitat Jaume I.

Subjects
chemistry.chemical_classification, biomass, 010405 organic chemistry, Chemistry, Organic Chemistry, sugar acids, chemistry.chemical_element, Biomass, iridium, 010402 general chemistry, 01 natural sciences, Catalysis, Sugar acids, 0104 chemical sciences, Inorganic Chemistry, sugars, dehydrogenation, 540 Chemistry, Organic chemistry, Dehydrogenation, Iridium, Physical and Theoretical Chemistry
Abstract

This is the pre-peer reviewed version of the following article: Selective conversion of various monosaccharaides into sugar acids by additive‐free dehydrogenation in water, which has been published in final form at https://doi.org/10.1002/cctc.202000544. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions. Abundant sugars of five and six carbon atoms are promising candidates for the production of valuable platform chemicals. Here, we describe the catalytic dehydrogenation of several pentoses and hexoses into their corresponding sugar acids with the concomitant formation of molecular hydrogen. This biomass transformation is promoted by highly active and selective catalysts based on iridium‐(III) complexes containing a triazolylidene as mesoionic carbene ligand (MIC). Monosaccharides are converted into sugar acids in an easy and sustainable manner using only catalyst and water, and in contrast to previously reported procedures, in the absence of any additive. The reaction is therefore very clean, and moreover highly selective, which avoids the tedious purification and product separation. Mechanistic investigations using 1 H NMR and UV‐vis spectroscopies and ESI mass spectrometry (ESI‐MS) indicates the formation of an unprecedented diiridium‐hydride as dormant species that correspond to the catalyst resting state.

Published
2020

4. C-Halide bond cleavage by a two-coordinate iron( i ) complex

Author

C. G. Werncke, Laure Vendier, Sylviane Sabo-Etienne, J. Pfeiffer, Sébastien Bontemps, Igor Müller, Philipps Universität Marburg, Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), DFG (grant WE 5627/4-1), CNRS, and ANR-12-BS07-0011,IRONHYC,Complexes de fer polyhydrures et catalyse d'hydrofonctionnalisation(2012)

Subjects
010405 organic chemistry, Chemistry, Stereochemistry, chemistry.chemical_element, Halide, 010402 general chemistry, 01 natural sciences, 0104 chemical sciences, Catalysis, Inorganic Chemistry, Cleave, Reactivity (chemistry), [CHIM.COOR]Chemical Sciences/Coordination chemistry, Carbon, Bond cleavage
Abstract

International audience; Iron(i) species are debated as key intermediates during the C-halide activation step in Kumuda type C-C cross-coupling catalysis. However, there is only limited knowledge on the reactivity of isolable iron(i) complexes towards organohalides. Using the known two-coordinate iron(i) complex K{18c6}[FeI(N(SiMe3)2)2] we disclose its proficiency to rapidly cleave different types of carbon halide bonds including even C-F bonds. Mechanistic studies indicate stepwise one-electron processes with the involvement of organoradicals.

Published
2019
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5. Cobalt Hexacyanoferrate on BiVO4 Photoanodes for Robust Water Splitting

Author

Franziska Simone Hegner, Drialys Cardenas-Morcoso, Isaac Herraiz-Cardona, José Ramón Galán-Mascarós, Sixto Gimenez, Núria López, We would like to acknowledge financial support from the University Jaume I through the P11B2014-51 project, and from the Generalitat Valenciana through the Santiago Grisolia Program, grant 2015-031. Serveis Centrals at UJI (SCIC) are also acknowledged. This work was also supported by the European Union (project ERC StG grant CHEMCOMP no. 279313), the Spanish Ministerio de Economía y Competitividad (MINECO) through projects CTQ2015-71287-R, CTQ2015-68770-R, and the Severo Ochoa Excellence Accreditation 2014-2018 SEV-2013-0319, and the Generalitat de Catalunya (2014SGR-797 and 2014SGR-199), and the CERCA Programme/Generalitat de Catalunya. Additionally, the 'LaCaixa'-Severo Ochoa International Programme of Ph.D. Scholarships (Programa internacional de Becas 'LaCaixa'-Severo Ochoa) is acknowledged for F.S. Hegner’s predoctoral grant. We thank BSC-RES for generous computational resources.

Subjects
Materials science, 02 engineering and technology, 010402 general chemistry, Photochemistry, Electrochemistry, 01 natural sciences, 7. Clean energy, water splitting, Catalysis, oxygen evolution, chemistry.chemical_compound, General Materials Science, Photocurrent, Prussian blue, Oxygen evolution, 021001 nanoscience & nanotechnology, computational chemistry, 0104 chemical sciences, chemistry, electrochemistry, photoelectrocatalysis, Water splitting, Reversible hydrogen electrode, Density functional theory, 0210 nano-technology
Abstract

The efficient integration of photoactive and catalytic materials is key to promoting photoelectrochemical water splitting as a sustainable energy technology built on solar power. Here, we report highly stable water splitting photoanodes from BiVO4 photoactive cores decorated with CoFe Prussian blue-type electrocatalysts (CoFe-PB). This combination decreases the onset potential of BiVO4 by ∼0.8 V (down to 0.3 V vs reversible hydrogen electrode (RHE)) and increases the photovoltage by 0.45 V. The presence of the catalyst also leads to a remarkable 6-fold enhancement of the photocurrent at 1.23 V versus RHE, while keeping the light-harvesting ability of BiVO4. Structural and mechanistic studies indicate that CoFe-PB effectively acts as a true catalyst on BiVO4. This mechanism, stemming from the adequate alignment of the energy levels, as showed by density functional theory calculations, allows CoFe-PB to outperform all previous catalyst/BiVO4 junctions and, in addition, leads to noteworthy longterm stability. A bare 10−15% decrease in photocurrent was observed after more than 50 h of operation under light irradiation

Published
2017

6. Linkage via K27 bestows ubiquitin chains with unique properties among polyubiquitins

Author

Susan Krueger, Megan R Reed, Mark A. Nakasone, T. Ashton Cropp, Olivier Walker, Apurva Chaturvedi, Emma K. Dixon, David Fushman, Carlos A. Castañeda, Joseph E. Curtis, Department of Chemistry [Syracuse, NY], Syracuse University, Ctr Biomol Struct & Org, University of Maryland [College Park], University of Maryland System-University of Maryland System, Dept Biol, Biophysics of complex systems, Institut des Sciences Analytiques (ISA), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Ctr Neutron Res, National Institute of Standards and Technology [Gaithersburg] (NIST), Dept Chem, Virginia Commonwealth University (VCU), This work was funded by an NSF postdoctoral award to C.A.C. and NIH R01 grants GM065334 and GM021248 to D.F. and GM084396 to T.A.C., utilized NMR instrumentation supported in part by NSF grant DBI1040158 and NIH shared instrumentation grant 1S10OD012254, and neutron-scattering facilities supported in part by the NSF under Agreement No. DMR-0944772, and and benefited from CCP-SAS software developed through a joint EPSRC (EP/K039121/1) and NSF (CHE-1265821) grant. We thank Konstantin Berlin for helpful discussions regarding SES. Some mass spectrometry data were collected on a Shimadzu 8040 mass spectrometer, supported in part by a Shimadzu instrumentation award to C.A.C.

Subjects
0301 basic medicine, Models, Molecular, Magnetic Resonance Spectroscopy, Protein Conformation, In silico, PROTEIN, Plasma protein binding, Computational biology, 010402 general chemistry, 01 natural sciences, MOLECULAR-COMPLEXES, 03 medical and health sciences, Protein structure, Ubiquitin, DOMAIN, Structural Biology, [CHIM.ANAL]Chemical Sciences/Analytical chemistry, Scattering, Small Angle, Humans, Binding site, [SDV.BBM.BC]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Biochemistry [q-bio.BM], Polyubiquitin, Conformational ensembles, Molecular Biology, MACROMOLECULES, SPECIFICITY, LIGASE, chemistry.chemical_classification, DNA ligase, Binding Sites, biology, [SDV.BBM.BS]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Structural Biology [q-bio.BM], Chemistry, ROTATIONAL DIFFUSION TENSOR, C-terminus, Lysine, Ubiquitination, RECOGNITION, [SDV.BBM.BM]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Molecular biology, DEGRADATION, 0104 chemical sciences, DNA-Binding Proteins, [SDV.BBM.BP]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Biophysics, 030104 developmental biology, DNA Repair Enzymes, Biochemistry, biology.protein, ORIENTATION, Protein Binding
Abstract

International audience; Polyubiquitination, a critical protein post-translational modification, signals for a diverse set of cellular events via the different isopeptide linkages formed between the C terminus of one ubiquitin (Ub) and the epsilon-amine of K6, K11, K27, K29, K33, K48, or K63 of a second Ub. We assembled di-ubiquitins (Ub(2)) comprising every lysine linkage and examined them biochemically and structurally. Of these, K27-Ub(2) is unique as it is not cleaved by most deubiquitinases. As this remains the only structurally uncharacterized lysine linkage, we comprehensively examined the structures and dynamics of K27-Ub(2) using nuclear magnetic resonance, small-angle neutron scattering, and in silico ensemble modeling. Our structural data provide insights into the functional properties of K27-Ub(2), in particular that K27-Ub(2) may be specifically recognized by K48-selective receptor UBA2 domain from proteasomal shuttle protein hHR23a. Binding studies and mutagenesis confirmed this prediction, further highlighting structural/recognition versatility of polyubiquitins and the potential power of determining function from elucidation of conformational ensembles

Published
2016
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7. Structure properties relationship study of electron-deficient dihydroindeno [2,1-b]fluorene derivatives for n-type Organic Field Effect Transistors

Author

Joëlle Rault-Berthelot, M. Chevrier, Maxime Romain, Tayeb Mohammed-Brahim, Cyril Poriel, Sarah Bebiche, Emmanuel Jacques, Institut des Sciences Chimiques de Rennes (ISCR), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA), Institut d'Électronique et des Technologies du numéRique (IETR), Nantes Université (NU)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), MC wishes to thank the Agence National de la Recherche (Project ANR HOME-OLED n°ANR-11-BS07-020-01) for a studentship. CP wishes to thank the UMR CNRS 6226-Institut des Sciences Chimiques de Rennes for an 'Inter UMR' grant. We thank the Region Bretagne and the Agence de l'Environnement et de la Maîtrise de l'Energie (ADEME) for a studentship (MR), the University of Rennes 1 for financial support (Action Incitative 2013), Sébastien Thiery (Rennes) for his help in organic synthesis and photophysical characterization, the C.R.M.P.O. (Rennes) for mass and elemental analyses, the GENCI for allocation of computing time under project c2015085032 and the ISA (Lyon) for TGA analysis., ANR-11-BS07-0020,HOME-OLED,Design de Matériaux hôtes pour des Diodes Organiques Electrophosphorescentes bleues haute performance : une nouvelle approche(2011), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Université de Nantes (UN)-Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), Université de Rennes 1 (UR1), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), and Université de Nantes (UN)-Université de Rennes 1 (UR1)

Subjects
Electron mobility, Materials science, 010405 organic chemistry, Stereochemistry, Triphenylene, General Chemistry, Fluorene, Photoresist, 010402 general chemistry, Electrochemistry, 01 natural sciences, 0104 chemical sciences, Threshold voltage, chemistry.chemical_compound, Crystallography, chemistry, Materials Chemistry, [CHIM]Chemical Sciences, Field-effect transistor, HOMO/LUMO
Abstract

International audience; A bridged syn triphenylene deriv., namely 5,7-dihydroindeno[2,1-b]fluorene, functionalized with dicyanovinylene units (2,1-b)-IF(♂C(CN)2)2 has been designed, synthesized and characterized. Its optical and electrochem. properties have been carefully studied through a combined exptl. and theor. approach and compared to those of three other structurally related dihydro[2,1-b]indenofluorene derivs. bearing methylenes, (2,1-b)-IF, carbonyls, (2,1-b)-IF(♂O)2, or both carbonyl and dicyanovinylene, (2,1-b)-IF(♂O)(♂C(CN)2) on the bridgeheads. (2,1-b)-IF(♂C(CN)2)2, which possesses a very low LUMO level, ca. -3.81 eV, has been successfully used as an active layer in n-channel OFETs using an epoxy based photoresist SU-8 as the gate insulator. (2,1-b)-IF(♂C(CN)2)2 based n-channel OFETs show promising properties such as a low threshold voltage functioning of 7.2 V (low gate-source and drain-source voltages), a high ratio between the on and the off currents (6.3 × 105), interesting subthreshold swing (SS = 2.16) and electron mobility (\textgreater10-3 cm2 V-1 s-1) and excellent stability under elec. stress. This elec. stability has allowed the incorporation of (2,1-b)-IF(♂C(CN)2)2 based n-channel OFETs in an integrated circuit. Thus, as a proof of concept, pseudo CMOS inverters made of n-type (2,1-b)-IF(♂C(CN)2)2-based OFETs have been fabricated and characterized highlighting the potential of this new family of materials.

Published
2015
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8. Revealing defects in crystalline lithium-ion battery electrodes by solid state NMR: applications to LiVPO4F

Author

Jean-Marcel Ateba, Robert J. Messinger, Michel Ménétrier, Christian Masquelier, Mathieu Duttine, Adrien Boulineau, Dominique Massiot, Dany Carlier, Laurence Croguennec, Michaël Deschamps, Elodie Salager, Conditions Extrêmes et Matériaux : Haute Température et Irradiation (CEMHTI), Université d'Orléans (UO)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Réseau sur le stockage électrochimique de l'énergie (RS2E), Université de Nantes (UN)-Aix Marseille Université (AMU)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Collège de France (CdF (institution))-Université de Picardie Jules Verne (UPJV)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Pau et des Pays de l'Adour (UPPA)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA)-Université Grenoble Alpes (UGA), Advanced Lithium Energy Storage Systems - ALISTORE-ERI (ALISTORE-ERI), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie de la Matière Condensée de Bordeaux (ICMCB), Université de Bordeaux (UB)-Institut Polytechnique de Bordeaux-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Innovation pour les Technologies des Energies Nouvelles et les nanomatériaux (LITEN), Institut National de L'Energie Solaire (INES), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Laboratoire réactivité et chimie des solides - UMR CNRS 7314 (LRCS), Université de Picardie Jules Verne (UPJV)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), European Union Seventh Framework Programme (FP7/2007-2013) under grant agreement 330735, European Research Network ALISTORE-ERI for a Ph.D. grant. We thank Région Aquitaine and the TGIR-RMN-THC (Fr3050 CNRS)., Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université d'Orléans (UO), Université de Picardie Jules Verne (UPJV)-Institut de Chimie du CNRS (INC)-Aix Marseille Université (AMU)-Université de Pau et des Pays de l'Adour (UPPA)-Université de Nantes (UN)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Collège de France (CdF (institution))-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA)-Université Grenoble Alpes (UGA)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut Polytechnique de Bordeaux-Université de Bordeaux (UB), Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), and Université de Picardie Jules Verne (UPJV)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)

Subjects
Spin states, General Chemical Engineering, Intercalation (chemistry), Analytical chemistry, chemistry.chemical_element, 02 engineering and technology, General Chemistry, [CHIM.MATE]Chemical Sciences/Material chemistry, 010402 general chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, Lithium-ion battery, 0104 chemical sciences, Paramagnetism, chemistry, Solid-state nuclear magnetic resonance, Chemical physics, Electrode, Scanning transmission electron microscopy, Materials Chemistry, Lithium, 0210 nano-technology
Abstract

International audience; Identifying and characterizing defects in crystalline solids is a challenging problem, particularly for lithium-ion intercalation materials, which often exhibit multiple stable oxidation and spin states as well as local ordering of lithium and charges. Here, we reveal the existence of characteristic lithium defect environments in the crystalline lithium-ion battery electrode LiVPO4F and establish the relative subnanometer-scale proximities between them. Well-crystallized LiVPO4F samples were synthesized with the expected tavorite-like structure, as established by X-ray diffraction (XRD) and scanning transmission electron microscopy (STEM) measurements. Solid-state 7Li nuclear magnetic resonance (NMR) spectra reveal unexpected paramagnetic 7Li environments that can account for up to 20% of the total lithium content. Multidimensional and site-selective solid-state 7Li NMR experiments using finite-pulse radio frequency-driven recoupling (fp-RFDR) establish unambiguously that the unexpected lithium environments are associated with defects within the LiVPO4F crystal structure, revealing the existence of dipole–dipole-coupled defect pairs. The lithium defects exhibit local electronic environments that are distinct from lithium ions in the crystallographic LiVPO4F site, which result from altered oxidation and/or spin states of nearby paramagnetic vanadium atoms. The results provide a general strategy for identifying and characterizing lithium defect environments in crystalline solids, including paramagnetic materials with short 7Li NMR relaxation times on the order of milliseconds.

Published
2015
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