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22 results on '"Samuel Drouet"'

1. Can Ni Complexes Behave as Molecular Water Oxidation Catalysts?

Author

Jordi Benet-Buchholz, Antoni Llobet, Carolina Gimbert-Suriñach, Sergi Grau, Pablo Garrido-Barros, and Samuel Drouet

Subjects
010405 organic chemistry, Chemistry, Nickel oxide, Inorganic chemistry, General Chemistry, 010402 general chemistry, 01 natural sciences, Catalysis, 0104 chemical sciences, Homogeneous, Water splitting, Nickel catalyst, Heterogeneous water oxidation
Abstract

The present report uncovers the borderline between homogeneous and heterogeneous water oxidation catalysis using a family of Ni complexes containing oxamidate anionic type of ligands. In particular, the Ni complex [(L1)NiII]2- (12-; L1 = o-phenylenebis(oxamidate)) and its modified analogues [(L2)NiII]2- (22- ;L2 = 4,5-dimethyl-1,2-phenylenebis(oxamidate)) and [(L3)NiII]2- (32- ;L2 = 4- methoxy-1,2-phenylenebis(oxamidate)) have been prepared and evaluated as molecular water oxidation catalysts at basic pH. Their redox features have been analyzed by mean of electrochemical measurements revealing a crucial involvement of the ligand in the electron transfer processes. Moreover, the stability of those complexes has been assessed both in solution and immobilized on graphene-based electrodes at different potentials and pHs. The degradation of the molecular species generates a NiOx layer, whose stability and activity as water oxidation catalyst has also been stablished. Electrochemical methods, together with surface characterization techniques, have shown the complex mechanistic scenario in water oxidation catalyzed by this family of Ni complexes, which consists of the coexistence of two catalytic mechanism: a homogeneous pathway driven by the molecular complex and a heterogeneous pathway based on NiOx. The electronic perturbations exerted through the ligand framework has manifested a strong influence over the stability of the molecular species under turnover conditions. Finally, 12- has been used as a molecular precursor for the formation of NiFeOx anodes that behave as extremely powerful water oxidation anodes.

Published
2019
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2. TiO 2 -mediated visible-light-driven hydrogen evolution by ligand-capped Ru nanoparticles

Author

Ivan Salmeron-Sànchez, Nuria Romero, Ona Illa, Laia Gil, Renan Barrach Guerra, Jordi García-Antón, Mirco Natali, Xavier Sala, Karine Philippot, Samuel Drouet, Departament de Química [Barcelona] (UAB), Universitat Autònoma de Barcelona (UAB), Universidade Estadual de Campinas = University of Campinas (UNICAMP), Laboratoire de chimie de coordination (LCC), Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Università degli Studi di Ferrara = University of Ferrara (UniFE), MINECO/FEDER project CTQ2015-64261-R, CNRS, University Paul Sabatier - Toulouse, University of Ferrara (FAR2019), University of Campinas [Campinas] (UNICAMP), 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), and Università degli Studi di Ferrara (UniFE)

Subjects
Materials science, Renewable Energy, Sustainability and the Environment, Kinetics, Energy Engineering and Power Technology, Quantum yield, Nanoparticle, Ambientale, 02 engineering and technology, 010402 general chemistry, 021001 nanoscience & nanotechnology, Photochemistry, 01 natural sciences, 0104 chemical sciences, Catalysis, Nanomaterials, Electron transfer, Fuel Technology, Triethanolamine, Photocatalysis, medicine, [CHIM.COOR]Chemical Sciences/Coordination chemistry, SDG 7 - Affordable and Clean Energy, 0210 nano-technology, medicine.drug
Abstract

International audience; Ru nanomaterials have recently emerged as potential substitutes for classical Pt-based cathodes for the hydrogen evolution reaction (HER). In this regard, nanoparticle surface-functionalization through the so-called organometallic approach is a promising strategy towards synthesizing tailored highly active and durable HER (photo)electrocatalysts with limitless tunability. Herein, efficient (turnover numbers over 480 molH2 molRu−1 and a turnover frequency of 21.5 molH2 h−1 molRu−1; apparent quantum yield of 1.3%) and durable (>100 h) visible-light-driven hydrogen evolution has been achieved at neutral pH with a ternary hybrid nanomaterial combining 4-phenylpyridine-capped Ru nanoparticles (RuPP), TiO2 nanocrystals and [Ru(bpy)2(4,4′-(PO3H2)2(bpy))]Cl2 (RuP) using triethanolamine (TEOA) as a sacrificial electron-donor. Photophysical analysis by means of transient absorption spectroscopy has been performed in order to shed light on the kinetics of the electron transfer events and to identify the rate-determining step of the overall photocatalytic process. TiO2 is shown to have a key role as (1) the support aiding the dispersion of the photocatalyst and limiting its agglomeration under turnover conditions and (2) the electron-transfer mediator enabling efficient electron communication between the catalyst and the anchored molecular photoabsorber. Finally, the evolution and fate of the photocatalyst in long-term HER photocatalysis are thoroughly analyzed.

Published
2020
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3. A porous Ru nanomaterial as an efficient electrocatalyst for the hydrogen evolution reaction under acidic and neutral conditions

Author

Xavier Sala, Vincent Collière, Samuel Drouet, Catherine Amiens, Jordi Creus, Karine Philippot, Jordi García-Antón, 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), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Departament de Química [Barcelona] (UAB), and Universitat Autònoma de Barcelona (UAB)

Subjects
Materials science, Inorganic chemistry, Metals and Alloys, 02 engineering and technology, General Chemistry, Overpotential, 010402 general chemistry, 021001 nanoscience & nanotechnology, Electrocatalyst, 7. Clean energy, 01 natural sciences, Durability, Catalysis, 0104 chemical sciences, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, Nanomaterials, Materials Chemistry, Ceramics and Composites, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Hydrogen evolution, 0210 nano-technology, Porosity, Current density
Abstract

International audience; A porous Ru nanomaterial exhibits high electrocatalytic performance and excellent durability for the hydrogen evolution reaction (HER) under both acidic and neutral conditions. It displays a low overpotential of 83 mV at a current density of 10 mA cm-2 and an excellent durability up to 12 h in 0.5 M H2SO4.

Published
2017
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4. Light-driven water oxidation using hybrid photosensitizer-decorated Co3O4 nanoparticles

Author

Nuria Romero, Antoni Llobet, Samuel Drouet, Sergey A. Denisov, Jonathan De Tovar, Jordi García-Antón, Pierre Lecante, Carolina Gimbert-Suriñach, Zoraida Freixa, Catherine Amiens, Karine Philippot, Vincent Collière, Roger Bofill, Diana Ciuculescu-Pradines, Nathan D. McClenaghan, Xavier Sala, Departament de Química [Barcelona] (UAB), Universitat Autònoma de Barcelona (UAB), Institut des Sciences Moléculaires (ISM), Université Montesquieu - Bordeaux 4-Université Sciences et Technologies - Bordeaux 1 (UB)-École Nationale Supérieure de Chimie et de Physique de Bordeaux (ENSCPB)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institute of Chemical Research of Catalonia (ICIQ), Laboratoire de chimie de coordination (LCC), Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Centre d'élaboration de matériaux et d'études structurales (CEMES), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut de Chimie de Toulouse (ICT), Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Facultad de Quimica de San Sebastian, Universidad del Pais Vasco, Universidad del Pais Vasco / Euskal Herriko Unibertsitatea [Espagne] (UPV/EHU), Ikerbasque - Basque Foundation for Science, Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT), Université Montesquieu - Bordeaux 4-Université Sciences et Technologies - Bordeaux 1-École Nationale Supérieure de Chimie et de Physique de Bordeaux (ENSCPB)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), 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), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA), Basque Foundation for Science (Ikerbasque), and Université Fédérale Toulouse Midi-Pyrénées

Subjects
Water oxidation, Materials science, Materials Science (miscellaneous), Energy Engineering and Power Technology, Nanoparticle, chemistry.chemical_element, 02 engineering and technology, Glassy carbon, 010402 general chemistry, Photochemistry, Electrocatalyst, 7. Clean energy, 01 natural sciences, Catalysis, Transition metal, Co3O4 nanoparticles, [CHIM]Chemical Sciences, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Photocatalysis, Renewable Energy, Sustainability and the Environment, Dyad systems, 021001 nanoscience & nanotechnology, Nanomaterial-based catalyst, 0104 chemical sciences, Fuel Technology, Nuclear Energy and Engineering, chemistry, 0210 nano-technology, Electrocatalysis, Cobalt
Abstract

Cobalt nanoparticles (NPs) have been prepared by hydrogenation of the organometallic complex [Co(η 3 -C 8 H 13 )(η 4 -C 8 H 12 )] in 1-heptanol in the absence of any other stabilizer and then transformed into Co 3 O 4 NPs using mild oxidative reaction conditions. After deposition onto glassy carbon rotating disk electrodes, the electrocatalytic performance of the Co 3 O 4 NPs in water oxidation has been tested in 1M NaOH. The activity has been benchmarked with that of state-of-the-art Co 3 O 4 NPs through electrochemically-active surface area (ECSA) and specific current density measurements. Furthermore, the covalent grafting of photosensitive polypyridyl-based Ru II complexes onto the surface of Co 3 O 4 NPs afforded hybrid nanostructured materials able to photo-oxidize water into O 2 , while steady-state and time-resolved spectroscopic measurements gave some further insight into kinetics and pertinent reaction steps following excitation. These first-row transition metal oxide hybrid nanocatalysts display better catalytic performance than simple mixtures of non-grafted photosensitizers and Co 3 O 4 NPs, thus evidencing the advantage of the direct coupling between the two entities for the photo-induced water oxidation reaction.

Published
2018
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5. Fluorenyl porphyrins for combined two-photon excited fluorescence and photosensitization

Author

Samuel Drouet, Areej Merhi, Dandan Yao, Mireille Blanchard-Desce, Christine O. Paul-Roth, Olivier Mongin, Vincent Hugues, 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 des Sciences Moléculaires (ISM), Centre National de la Recherche Scientifique (CNRS)-École Nationale Supérieure de Chimie et de Physique de Bordeaux (ENSCPB)-Université Sciences et Technologies - Bordeaux 1-Université Montesquieu - Bordeaux 4-Institut de Chimie du CNRS (INC), China Scholarship Council, Federación Española de Enfermedades Raras, UEB, 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), and Université Montesquieu - Bordeaux 4-Université Sciences et Technologies - Bordeaux 1 (UB)-École Nationale Supérieure de Chimie et de Physique de Bordeaux (ENSCPB)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Chemistry, Singlet oxygen, Dimer, fluorenyl porphyrin two photon excited fluorescence photosensitization, General Physics and Astronomy, Trimer, Photochemistry, Fluorescence, 3. Good health, chemistry.chemical_compound, Excited state, Dendrimer, Tetraphenylporphyrin, [CHIM]Chemical Sciences, Physical and Theoretical Chemistry, Luminescence
Abstract

International audience; The two-photon absorption (2PA), the luminescence and the photosensitization properties of porphyrin-cored fluorenyl dendrimers and meso-substituted fluorenylporphyrin monomer, dimer and trimer are described. In comparison with model tetraphenylporphyrin, these compds. combine enhanced (non-resonant) 2PA cross-sections in the near IR and enhanced fluorescence quantum yields, together with maintained singlet oxygen generation quantum yields. 'Semi-disconnection' between fluorenyl groups and porphyrins (i.e. direct meso substitution) proved to be more efficient than non-conjugated systems (based on efficient FRET between fluorenyl antennae and porphyrins). These results are of interest for combined two-photon imaging and photodynamic therapy.

Published
2015
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7. Proton-Coupled Electron Transfer Cleavage of Heavy-Atom Bonds in Electrocatalytic Processes. Cleavage of a C–O Bond in the Catalyzed Electrochemical Reduction of CO2

Author

Guillaume Passard, Marc Robert, Cyrille Costentin, Jean-Michel Savéant, and Samuel Drouet

Subjects
Colloid and Surface Chemistry, Proton, Chemistry, Atom, General Chemistry, Proton-coupled electron transfer, Cleavage (embryo), Photochemistry, Electrochemistry, Biochemistry, Catalysis, Bond cleavage
Abstract

Most of the electrocatalytic processes of interest in the resolution of modern energy challenges are associated with proton transfer. In the cases where heavy atom bond cleavage occurs concomitantly, the question arises of the exact nature of its coupling with proton-electron transfer within the catalytic cycle. The cleavage of a C-O bond in the catalyzed electrochemical conversion of CO2 to CO offers the opportunity to address this question. Electrochemically generated iron(0) porphyrins are efficient, specific, and durable catalysts provided they are coupled with Lewis or Brönsted acids. The cocatalyst properties of four Brönsted acids of increasing strength, water, trifluoroethanol, phenol, and acetic acid, have been systematically investigated. Preparative-scale electrolyses showed that carbon monoxide is the only product of the catalytic reaction. Methodic application of a nondestructive technique, cyclic voltammetry, with catalyst and CO2 concentrations, as well as H/D isotope effect, as diagnostic parameters allowed the dissection of the reaction mechanism. It appears that the key step of the reaction sequence consists of an electron transfer from the catalyst concerted with the cleavage of a C-O bond and the transfer of one proton. This is the second example, and an intermolecular version of such a concerted proton-electron bond-breaking reaction after a similar electrochemical process involving the cleavage of O-O bonds has been identified. It is the first time that a proton-electron transfer concerted with bond breaking has been uncovered as the crucial step in a catalytic multistep reaction.

Published
2013
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8. Cubic nonlinear optical properties of new zinc tetraphenyl porphyrins peripherally functionalized with electron-rich Ru(II) alkynyl substituents

Author

Marek Samoc, Areej Merhi, Katarzyna Matczyszyn, Małgorzata Wielgus, Christine O. Paul-Roth, Samuel Drouet, Frédéric Paul, Marie P. Cifuentes, Joanna Olesiak-Banska, Mark G. Humphrey, Dandan Yao, 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), Australian National University (ANU), Institute of Physical and Theoretical Chemistry, Wroclaw University of Science and Technology, Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES), Université Européenne de Bretagne (UEB), FEDER, RTR BRESMAT, CNRS [5676], Ministère National de la Recherche et de la Technologie (MNERT), Région Bretagne, China Scholarship Council (CSC), Foundation for Polish Science Welcome grant, Polish Ministry of Science and Higher Education, Australian Research Council, ARC, 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), and Institut National des Sciences Appliquées (INSA)

Subjects
Nonlinear optics, ORGANIC MATERIALS, Stereochemistry, chemistry.chemical_element, Zinc, Electron, 010402 general chemistry, 01 natural sciences, Biochemistry, Chemical reaction, Porphyrin, RUTHENIUM COMPLEXES, chemistry.chemical_compound, ORGANOMETALLIC COMPLEXES, Polarizability, ARYL GROUP, FLUORENONE PENDANT ARMS, Drug Discovery, Tetraphenylporphyrin, DENDRIMERS, Pi-conjugation, [CHIM.ORGA]Chemical Sciences/Organic chemistry, 010405 organic chemistry, Organic Chemistry, Organometallics, Block (periodic table), DIMERS, 3. Good health, 0104 chemical sciences, Crystallography, 2-PHOTON ABSORPTION, chemistry, METAL-COMPLEXES, 3RD-ORDER, Acetylide complex
Abstract

We report the synthesis and characterization of new organometallic assemblies consisting of a central Zn(II) tetraphenylporphyrin (ZnTPP) core surrounded by four Ru(II) alkynyl complexes ( trans -Ru(dppe) 2 R) appended at the para phenyl positions and acting as peripheral donor groups. The synthesis of the tetra-chlorido derivative 2 (R=Cl) is reported first, followed by that of three extended homologues ( 3 –X) obtained from this building block by substitution of the chlorido ligands by functionalized arylacetylenes (R=C C(4-C 6 H 4 X); X=NO 2 , H, OMe). Measurement of the nonlinear absorption properties of the pentametallic derivatives 3 –X reveals that these extended π-networks incorporating polarizable organometallic units behave as good two-photon absorbers in the visible and near-IR range.

Published
2012
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9. Synthesis and photophysical properties of porphyrins with fluorenyl pendant arms

Author

Samuel Drouet, Christine O. Paul-Roth, and Gérard Simonneaux

Subjects
Organic Chemistry, Quantum yield, Fluorene, Photochemistry, Biochemistry, Porphyrin, Fluorescence, Chemical synthesis, chemistry.chemical_compound, chemistry, Drug Discovery, Tetraphenylporphyrin, Polymer chemistry, Luminescence
Abstract

Symmetrical-A4-porphyrins bearing four fluorene donor moieties TOFP (5,10,15,20-tetra(4-(2 methyloxyfluorenyl)phenyl)porphyrin) as well as eight fluorene arms OOFP (5,10,15,20-octa(3,5-(2-methyloxyfluorenyl)phenyl)porphyrin) were synthesized and characterized. Preliminary photophysical properties are reported. In comparison to the reference tetraphenylporphyrin TPP, the luminescence properties are slightly improved. The fluorescence quantum yields of tetrafluorenylporphyrin TOFP (1) and octafluorenylporphyrin OOFP (2) are 0.10 and 0.13, respectively.

Published
2009
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10. Redox Non-innocent Ligand Controls Water Oxidation Overpotential in a New Family of Mononuclear Cu-Based Efficient Catalysts

Author

Jordi Benet-Buchholz, Pablo Garrido-Barros, Antoni Llobet, Feliu Maseras, Samuel Drouet, and Ignacio Funes-Ardoiz

Subjects
Chemistry, Ligand, General Chemistry, Overpotential, Ring (chemistry), Photochemistry, Biochemistry, Medicinal chemistry, Redox, Catalysis, Non-innocent ligand, Metal, Colloid and Surface Chemistry, Catalytic cycle, visual_art, visual_art.visual_art_medium
Abstract

A new family of tetra-anionic tetradentate amidate ligands, N1,N1′-(1,2-phenylene)bis(N2-methyloxalamide) (H4L1), and its derivatives containing electron-donating groups at the aromatic ring have been prepared and characterized, together with their corresponding anionic Cu(II) complexes, [(LY)Cu]2–. At pH 11.5, the latter undergoes a reversible metal-based III/II oxidation process at 0.56 V and a ligand-based pH-dependent electron-transfer process at 1.25 V, associated with a large electrocatalytic water oxidation wave (overpotential of 700 mV). Foot-of-the-wave analysis gives a catalytic rate constant of 3.6 s–1 at pH 11.5 and 12 s–1 at pH 12.5. As the electron-donating capacity at the aromatic ring increases, the overpotential is drastically reduced down to a record low of 170 mV. In addition, DFT calculations allow us to propose a complete catalytic cycle that uncovers an unprecedented pathway in which crucial O–O bond formation occurs in a two-step, one-electron process where the peroxo intermediate generated has no formal M–O bond but is strongly hydrogen bonded to the auxiliary ligand. &nbsp

Published
2015

11. ChemInform Abstract: Molecular Artificial Photosynthesis

Author

Serena Berardi, Laia Francàs, Carolina Gimbert-Suriñach, Miguel Guttentag, Antoni Llobet, Thibaut Stoll, Craig J. Richmond, and Samuel Drouet

Subjects
Primary (chemistry), Primary energy, business.industry, Chemistry, Artificial systems, Fossil fuel, Energy transformation, General Medicine, business, Process engineering, Solar fuel, Artificial photosynthesis, Renewable energy
Abstract

The replacement of fossil fuels by a clean and renewable energy source is one of the most urgent and challenging issues our society is facing today, which is why intense research has been devoted to this topic recently. Nature has been using sunlight as the primary energy input to oxidise water and generate carbohydrates (solar fuel) for over a billion years. Inspired, but not constrained, by nature, artificial systems can be designed to capture light and oxidise water and reduce protons or other organic compounds to generate useful chemical fuels. This tutorial review covers the primary topics that need to be understood and mastered in order to come up with practical solutions for the generation of solar fuels. These topics are: the fundamentals of light capturing and conversion, water oxidation catalysis, proton and CO2 reduction catalysis and the combination of all of these for the construction of complete cells for the generation of solar fuels.

Published
2014
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12. Synthesis of platinum complexes of Fluorenyl-substituted Porphyrins used as Phosphorescent dyes for solution-processed organic light-emitting devices

Author

Areej Merhi, J.A.G. Williams, Louise F. Gildea, Samuel Drouet, Christine O. Paul-Roth, Michael C. Petty, Christopher Pearson, Organométalliques: Matériaux et Catalyse, 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)-Université de Rennes (UNIV-RENNES)-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)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR), Institut des Sciences Chimiques de Rennes (ISCR), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES), Department of Chemistry, Durham University, School of Engineering and Centre for Molecular and Nanoscale Electronics, This research was supported by grants from the 'Région Bretagne' (ARED - A. MERHI), the 'Ministère National de la Recherche et de la Technologie ' (MNERT - S. DROUET), and EPSRC (DTA studentship to L. F. GILDEA)., Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-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)-Université de Rennes (UR)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), 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), and Institut National des Sciences Appliquées (INSA)

Subjects
Porphyrins, Quantum yield, chemistry.chemical_element, Fluorene, 010402 general chemistry, Photochemistry, 01 natural sciences, Biochemistry, chemistry.chemical_compound, Drug Discovery, Tetraphenylporphyrin, OLED, Platinum, 010405 organic chemistry, Chemistry, Phosphorescence, OLEDs, Organic Chemistry, Porphyrin, 0104 chemical sciences, Light harvesting, Luminescence, [CHIM.OTHE]Chemical Sciences/Other
Abstract

International audience; Platinum(II) complexes of symmetrical meso-substituted A4-porphyrins bearing four fluorene donor moieties 5,10,15,20-tetra(4-(2 methyloxyfluorenyl)phenyl)porphyrin, referred to as TOFP, or eight fluorene arms, 5,10,15,20-octa(3,5-(2 methyloxyfluorenyl)phenyl)porphyrin, OOFP, were synthesised and characterised. The photophysical properties of the new compounds are reported and compared to those of PtTPP and PtTFP {TPP=tetraphenylporphyrin and TFP=tetra(2-fluorenyl)porphyrin}. The luminescence quantum yields of PtTOFP and PtOOFP are 11% and 4.2%, respectively, compared to 4.6% for the reference PtTPP and only 2.0% for the previously studied compound PtTFP. The electronic and optoelectronic behaviour of solution-processed organic light-emitting devices (OLEDs) are reported that incorporate these platinum porphyrins as phosphorescent dyes doped into different layers of a polyvinylcarbazole (PVK) host.

Published
2013
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13. Linear porphyrin dimers with fluorenyl arms linked by an ethynyl bridge

Author

Samuel Drouet, Nicolas Kerisit, Christine O. Paul-Roth, Areej Merhi, 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), Organométalliques: Matériaux et Catalyse, 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)-Université de Rennes (UNIV-RENNES)-Institut des Sciences Chimiques de Rennes (ISCR), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR), The authors are grateful to Region Bretagne for ARED grant for A.M., MRT for PhD grant concerning S.D. Partial Funding for the project was obtained from the 'Université Européenne de Bretagne' (UEB) and from FEDER by an EPT grant in the 'MITTSI' program from RTR BRESMAT., 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), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut des Sciences Chimiques de Rennes (ISCR), and 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 Rennes (UR)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Porphyrins, Luminescence, Stereochemistry, Dimer, Supramolecular chemistry, Quantum yield, Fluorene, 010402 general chemistry, 01 natural sciences, Biochemistry, chemistry.chemical_compound, Dendrimer, Drug Discovery, 010405 organic chemistry, Organic Chemistry, Porphyrin, 0104 chemical sciences, 3. Good health, Crystallography, Monomer, chemistry, [CHIM.OTHE]Chemical Sciences/Other
Abstract

International audience; A series of porphyrin monomers bearing fluorenyl donor groups is presented; successively, compounds 10, 11, 12, and 13 bearing three fluorenyl groups. Starting from these building blocks, the synthesis of new porphyrin ethynyl-linked dimers 7 and 8, bearing in totally six peripheral fluorenyl arms is attempted. Dimers are obtained by coupling two porphyrin monomers, using a palladium catalyst, by a rigid bridge. Luminescence studies of new dimers 7 and 8 are presented. We can then compare the detailed luminescence properties of these dimers with former porphyrin monomer possessing four fluorenyl arms TFP (2), which is the precursor model of this work, to porphyrin dendrimers bearing various numbers of fluorenyl arms (3 and 4) and finally to corresponding supramolecular assemblies (5 and 6).

Published
2013
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14. A local proton source enhances CO2 electroreduction to CO by a molecular Fe catalyst

Author

Cyrille Costentin, Marc Robert, Jean-Michel Savéant, and Samuel Drouet

Subjects
Electrolysis, Carbon Monoxide, Multidisciplinary, Chemistry, Commodity chemicals, Metalloporphyrins, Iron, Inorganic chemistry, Mineralogy, Electrochemical Techniques, Overpotential, Carbon Dioxide, Electrochemistry, Catalysis, law.invention, chemistry.chemical_compound, Phenols, law, Yield (chemistry), Carbon dioxide, Protons, Oxidation-Reduction, Carbon monoxide
Abstract

Lending a Hand to CO 2 Reduction Although plants and microbes have been reducing CO 2 with ease for millennia, people still find it extremely challenging. A cost-effective synthetic scheme for transforming CO 2 into fuels and commodity chemicals would be a double boon, lowering atmospheric concentration of the greenhouse gas while supplementing (and perhaps ultimately replacing) dwindling petroleum feedstocks. Toward this end, Costentin et al. (p. 90 ) show that an iron catalyst for the electrochemical reduction of CO 2 to CO gets an efficiency boost from phenol substituents appended to the ligand framework.

Published
2012

15. Synthesis of Luminescent Supramolecular Assemblies from Fluorenyl Porphyrins and Polypyridyl Isocyanurate-based Spacers

Author

Gilles Argouarch, Areej Merhi, Mireille Blanchard-Desce, Samuel Drouet, Christine O. Paul-Roth, Olivier Mongin, Frédéric Paul, 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), Chimie et Photonique Moléculaires (CPM), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS), Organométalliques: Matériaux et Catalyse, 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)-Université de Rennes (UNIV-RENNES)-Institut des Sciences Chimiques de Rennes (ISCR), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR), 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 Rennes (UR)-Centre National de la Recherche Scientifique (CNRS), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut des Sciences Chimiques de Rennes (ISCR), and 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 Rennes (UR)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Light-harvesting, Porphyrins, Supramolecular assemblies, Supramolecular chemistry, chemistry.chemical_element, Zinc, Fluorene, [CHIM.INOR]Chemical Sciences/Inorganic chemistry, 010402 general chemistry, Photochemistry, 01 natural sciences, Biochemistry, Chemical synthesis, Fluorescence, chemistry.chemical_compound, Drug Discovery, Red emission, 010405 organic chemistry, Ligand, Organic Chemistry, Chromophore, 0104 chemical sciences, chemistry, Luminescence
Abstract

International audience; Two new dendrimeric supramolecular assemblies bearing twelve and twenty-four fluorenyl peripheral donor groups surrounding an organic core have been prepared and studied. These assemblies are composed of three zinc porphyrins possessing each four (ZnTFP) and eight fluorenyl chromophores (ZnOOFP) linked together by a central tris-pyridyl organic ligand. Due to efficient energy transfer between the fluorenyl arms, which act as antennas, and the Zn centres, which act as emitters; these assemblies behave as red emitters after selective UV or visible irradiation. The kinetic stability of these supramolecular assemblies and its impact on their photophysical properties are discussed.

Published
2012
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16. Turnover numbers, turnover frequencies, and overpotential in molecular catalysis of electrochemical reactions. Cyclic voltammetry and preparative-scale electrolysis

Author

Cyrille Costentin, Jean-Michel Savéant, Samuel Drouet, and Marc Robert

Subjects
Tafel equation, Electrolysis, Chemistry, Inorganic chemistry, Analytical chemistry, General Chemistry, Overpotential, Electrochemistry, Biochemistry, Catalysis, law.invention, Turnover number, Colloid and Surface Chemistry, law, High current, Cyclic voltammetry
Abstract

The search for efficient catalysts to face modern energy challenges requires evaluation and comparison through reliable methods. Catalytic current efficiencies may be the combination of many factors besides the intrinsic chemical properties of the catalyst. Defining turnover number and turnover frequency (TOF) as reflecting these intrinsic chemical properties, it is shown that catalysts are not characterized by their TOF and their overpotential (η) as separate parameters but rather that the parameters are linked together by a definite relationship. The log TOF-η relationship can often be linearized, giving rise to a Tafel law, which allows the characterization of the catalyst by the value of the TOF at zero overpotential (TOF(0)). Foot-of-the-wave analysis of the cyclic voltammetric catalytic responses allows the determination of the TOF, log TOF-η relationship, and TOF(0), regardless of the side-phenomena that interfere at high current densities, preventing the expected catalytic current plateau from being reached. Strategies for optimized preparative-scale electrolyses may then be devised on these bases. The validity of this methodology is established on theoretical grounds and checked experimentally with examples taken from the catalytic reduction of CO(2) by iron(0) porphyrins.

Published
2012

17. Platinum and palladium complexes of fluorenyl porphyrins as red phosphors for light-emitting devices

Author

Samuel Drouet, a Christine O. Paul-Roth, ab Valeria Fattori, c Massimo Cocchi, c, J. A. Gareth Williams, d, Institut des Sciences Chimiques de Rennes (ISCR), 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), Institute of Organic Synthesis and Photoreactivity (ISOF), Consiglio Nazionale delle Ricerche [Roma] (CNR), 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), and National Research Council of Italy | Consiglio Nazionale delle Ricerche (CNR)

Subjects
010405 organic chemistry, Inorganic chemistry, chemistry.chemical_element, Phosphor, General Chemistry, Electroluminescence, 010402 general chemistry, Photochemistry, 01 natural sciences, Porphyrin, Catalysis, 0104 chemical sciences, chemistry.chemical_compound, chemistry, Tetraphenylporphyrin, Materials Chemistry, OLED, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Luminescence, Platinum, Palladium
Abstract

International audience; Platinum(II) and palladium(II) complexes of a porphyrin with fluorenyl groups linked directly at the meso-positions (TFP) have been synthesized and characterized. Their luminescence properties in solution have been studied under ambient conditions and at 77 K. Compared to the corresponding complexes of tetraphenylporphyrin TPP, the emission is red-shifted in both cases. Radiative rate constants are found to be enhanced by the fluorenyl substituents, although non-radiative decay rates are also increased in solution. Short-wavelength UV excitation leads to no detectable fluorenyl-based fluorescence, indicating that very efficient transfer of energy to the porphyrin occurs. An OLED in which PtTFP is used as a red phosphor has been prepared and its electroluminescence performance assessed. High current "roll-off" is significantly delayed to higher currents compared to previously described OLEDs that make use of standard platinum porphyrins as emitters, an effect which can be attributed to the shorter radiative lifetime of PtTFP.

Published
2011
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18. Fluorenyl dendrimer porphyrins: synthesis and photophysical properties

Author

Christine O. Paul-Roth, Samuel Drouet, 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), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and 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)

Subjects
010405 organic chemistry, [CHIM.ORGA]Chemical Sciences/Organic chemistry, Organic Chemistry, Fluorene, 010402 general chemistry, Photochemistry, 7. Clean energy, 01 natural sciences, Biochemistry, Chemical synthesis, Fluorescence, Porphyrin, First generation, 0104 chemical sciences, chemistry.chemical_compound, chemistry, Dendrimer, Drug Discovery, Red light, Luminescence, ComputingMilieux_MISCELLANEOUS
Abstract

New symmetrical dendrimeric type super-porphyrin bearing sixteen fluorenyl donor groups sixteen fluorenylporphyrin SOFP (1) have been synthesized and characterized. Preliminary photophysical properties are reported; in comparison to the references first generation dendrimer tetrafluorenylporphyrin TOFP (2) bearing four peripheral fluorenyl and second generation dendrimer octafluorenylporphyrin OOFP (3) bearing eight peripheral fluorenyl, the luminescence properties are slightly improved. It is found that the excitation energy transfer occurs from the sixteen fluorenyl units to the porphyrin core, following what the porphyrin emits intense red light.

Published
2009
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19. Scanning tunneling microscopy investigations of electropolymerized tetra-arylporphyrin complexes

Author

Joëlle Rault-Berthelot, Samuel Drouet, Pascal Turban, Christine O. Paul-Roth, Séverine Ballut, Institut des Sciences Chimiques de Rennes (ISCR), 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), Surfaces et interfaces, Institut de Physique de Rennes (IPR), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS), Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES), 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 Rennes (UR)-Centre National de la Recherche Scientifique (CNRS)-Université de Rennes (UR)-Centre National de la Recherche Scientifique (CNRS), and Institut National des Sciences Appliquées (INSA)

Subjects
Materials science, Nanostructure, Scanning electron microscope, Supramolecular chemistry, Zn-porphyrin, chemistry.chemical_element, Nanotechnology, 010402 general chemistry, 01 natural sciences, law.invention, law, Materials Chemistry, [CHIM]Chemical Sciences, Lamellar structure, chemistry.chemical_classification, Pt-porphyrin, 010405 organic chemistry, Anodizing, Metals and Alloys, Electropolymerization, Surfaces and Interfaces, Polymer, 0104 chemical sciences, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, Crystallography, Scanning tunnelling microscopy, chemistry, Scanning tunneling microscope, Platinum, Scanning electron microscopy
Abstract

International audience; Scanning tunneling microscopy (STM) studies on poly(Zinc-tetraphenylporphyrin) (poly(ZnTPP)) and poly(Zn- or Pt-tetradimethoxyphenylporphyrins) (poly(Zn8OMeTPP) or poly(Pt8OMeTPP)) deposited through anodic oxidation on platinum surfaces are reported. STM investigations on these metalloporphyrin films were conducted to obtain informations on the supramolecular architecture of these polymers. These STM images indicate that poly(ZnTPP) covered the metallic electrode with a layered structure. For poly(Zn8OMeTPP) and poly(Pt8OMeTPP) a tendency to form regular molecular assemblies is obvious.

Published
2009
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20. Comparative behabiour of the anodic oxidation of mono-,di- and tetra-arylporphyrins: Towards new electroactive materials with variable bandgaps

Author

Cyril Poriel, Christine O. Paul-Roth, Sandrine Juillard, Joëlle Rault-Berthelot, G. Simonneaux, Séverine Ballut, Samuel Drouet, 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), 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), and Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)

Subjects
Conductive polymer, biology, 010405 organic chemistry, Chemistry, Band gap, [CHIM.ORGA]Chemical Sciences/Organic chemistry, General Chemical Engineering, Aryl, Inorganic chemistry, 010402 general chemistry, biology.organism_classification, Electrochemistry, 01 natural sciences, Porphyrin, 0104 chemical sciences, Analytical Chemistry, chemistry.chemical_compound, Polymerization, Tetra, ComputingMilieux_MISCELLANEOUS, Dichloromethane
Abstract

The electrochemical studies of mono-, di- and tetra-arylporphyrins are presented. The anodic oxidation of di- and tetra-arylporphyrins leads to insoluble electroactive deposits with variable electrochemical bandgaps. Remarkably, for the monoarylporphyrin, the polymerization is also observed. The physico- and electrochemical behaviours of the deposits are presented. Possible coupling between aryl units and porphyrin meso positions is discussed in order to explain the electrochemical behaviour of the different deposit and the values of their electrochemical bandgap.

Published
2008
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22. Molecular artificial photosynthesis

Author

Samuel Drouet, Laia Francàs, Miguel Guttentag, Antoni Llobet, Thibaut Stoll, Carolina Gimbert-Suriñach, Serena Berardi, and Craig J. Richmond

Subjects
Primary (chemistry), Primary energy, 010405 organic chemistry, business.industry, Chemistry, Fossil fuel, Ambientale, Nanotechnology, General Chemistry, 010402 general chemistry, Solar fuel, 7. Clean energy, 01 natural sciences, 0104 chemical sciences, Renewable energy, Artificial photosynthesis, 13. Climate action, Artificial systems, business, Process engineering
Abstract

The replacement of fossil fuels by a clean and renewable energy source is one of the most urgent and challenging issues our society is facing today, which is why intense research has been devoted to this topic recently. Nature has been using sunlight as the primary energy input to oxidise water and generate carbohydrates (solar fuel) for over a billion years. Inspired, but not constrained, by nature, artificial systems can be designed to capture light and oxidise water and reduce protons or other organic compounds to generate useful chemical fuels. This tutorial review covers the primary topics that need to be understood and mastered in order to come up with practical solutions for the generation of solar fuels. These topics are: the fundamentals of light capturing and conversion, water oxidation catalysis, proton and CO2 reduction catalysis and the combination of all of these for the construction of complete cells for the generation of solar fuels.

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