Search

Your search keyword '"Laberty-Robert, Christel"' showing total 336 results
Start Over Author "Laberty-Robert, Christel"
336 results on '"Laberty-Robert, Christel"'

8. Angle-Resolved Linear Dichroism to Probe the Organization of Highly Ordered Collagen Biomaterials

Author

Krins, Natacha, Wien, Frank, Schmeltz, Margaux, Pérez, Javier, Dems, Dounia, Debons, Nicolas, Laberty-Robert, Christel, Schanne-Klein, Marie-Claire, and Aimé, Carole

Abstract

Controlling the assembly of high-order structures is central to soft-matter and biomaterial engineering. Angle-resolved linear dichroism can probe the ordering of chiral collagen molecules in the dense state. Collagen triple helices were aligned by solvent evaporation. Their ordering gives a strong linear dichroism (LD) that changes sign and intensity with varying sample orientations with respect to the beam linear polarization. Being complementary to circular dichroism, which probes the structure of chiral (bio)molecules, LD can shift from the molecular to the supramolecular scale and from the investigation of the conformation to interactions. Supported by multiphoton microscopy and X-ray scattering, we show that LD provides a straightforward route to probe collagen alignment, determine the packing density, and monitor denaturation. This approach could be adapted to any assembly of chiral (bio)macromolecules, with key advantages in detecting large-scale assemblies with high specificity to aligned and chiral molecules and improved sensitivity compared to conventional techniques.

Published
2024
Full Text
View/download PDF

17. Heterostructured Cobalt Silicide Nanocrystals: Synthesis in Molten Salts, Ferromagnetism, and Electrocatalysis

Author

Song, Yang, primary, Gómez-Recio, Isabel, additional, Ghoridi, Anissa, additional, Igoa Saldaña, Fernando, additional, Janisch, Daniel, additional, Sassoye, Capucine, additional, Dupuis, Vincent, additional, Hrabovsky, David, additional, Ruiz-González, M. Luisa, additional, González-Calbet, José M., additional, Casale, Sandra, additional, Zitolo, Andrea, additional, Lassalle-Kaiser, Benedikt, additional, Laberty-Robert, Christel, additional, and Portehault, David, additional

Published
2023
Full Text
View/download PDF

20. Molten Salts‐Driven Discovery of a Polar Mixed‐Anion 3D Framework at the Nanoscale: Zn4Si2O7Cl2, Charge Transport and Photoelectrocatalytic Water Splitting

Author

Kumar, Ram, primary, Song, Yang, additional, Ghoridi, Anissa, additional, Boullay, Philippe, additional, Rousse, Gwenaelle, additional, Gervais, Christel, additional, Coelho Diogo, Cristina, additional, Kabbour, Houria, additional, Sassoye, Capucine, additional, Beaunier, Patricia, additional, Castaing, Victor, additional, Viana, Bruno, additional, Luisa Ruiz Gonzalez, Maria, additional, Calbet, José Gonzalez, additional, Laberty‐Robert, Christel, additional, and Portehault, David, additional

Published
2023
Full Text
View/download PDF

23. Tuning the Valence of MnOx Cathodes Reveals the Universality of the Proton‐Coupled Electrodissolution/Electrodeposition Mechanism in Rechargeable Aqueous Zn Batteries.

Author

Singh, Arvinder, Laberty‐Robert, Christel, Balland, Véronique, and Limoges, Benoît

Subjects
*AQUEOUS electrolytes, *CATHODES, *MANGANESE oxides, *PHASE transitions, *OXIDATION states, *ELECTRIC batteries, *ELECTROPLATING
Abstract

The charge storage mechanism of manganese oxides (MnOx) in rechargeable mild aqueous Zn batteries is still a matter of debate, with no consensus on mechanism and charge carriers. In this work, this issue is addressed by relying on a quantitative and comparative electrochemical study of low‐valence crystalline MnOx cathodes in a range of aqueous electrolytes, with a primary focus on spinel Mn3O4. The results demonstrate that the oxidation state of Mn in MnOx structures as well as their degree of crystallinity have little impact on the electrochemical reactivity, all MnOx being fully converted into soluble Mn2+ upon discharge. It is further revealed that this electrodissolution mechanism is affected by Mn3O4 dismutation in the most acidic electrolytes. Accordingly, the true thermodynamics and kinetics of Mn3O4 are only accessible at mildly acidic to neutral pHs. In addition, the study confirms the phase transformation of Mn3O4 to Mn5O8 upon galvanostatic oxidation, and demonstrates that this transformation only proceeds in Mn2+‐free electrolytes, since otherwise amorphous MnO2 electrodeposits on top of Mn3O4. Finally, it is concluded that regardless of the starting MnOx material, after the first discharge or a first charge/discharge cycle, subsequent charge/discharge cycles rely on a reversible proton‐coupled electrodeposition of amorphous MnO2. [ABSTRACT FROM AUTHOR]

Published
2023
Full Text
View/download PDF

27. Molten Salts‐Driven Discovery of a Polar Mixed‐Anion 3D Framework at the Nanoscale: Zn4Si2O7Cl2, Charge Transport and Photoelectrocatalytic Water Splitting.

Author

Kumar, Ram, Song, Yang, Ghoridi, Anissa, Boullay, Philippe, Rousse, Gwenaelle, Gervais, Christel, Coelho Diogo, Cristina, Kabbour, Houria, Sassoye, Capucine, Beaunier, Patricia, Castaing, Victor, Viana, Bruno, Luisa Ruiz Gonzalez, Maria, Calbet, José Gonzalez, Laberty‐Robert, Christel, and Portehault, David

Subjects
CHEMICAL stability, ZINTL compounds, HOLE mobility, OXIDATION of water, FUSED salts, NANOSILICON
Abstract

Mixed‐anion compounds widen the chemical space of attainable materials compared to single anionic compounds, but the exploration of their structural diversity is limited by common synthetic paths. Especially, oxychlorides rely mainly on layered structures, which suffer from low stability during photo(electro)catalytic processes. Herein we report a strategy to design a new polar 3D tetrahedral framework with composition Zn4Si2O7Cl2. We use a molten salt medium to enable low temperature crystallization of nanowires of this new compound, by relying on tetrahedral building units present in the melt to build the connectivity of the oxychloride. These units are combined with silicon‐based connectors from a non‐oxidic Zintl phase to enable precise tuning of the oxygen content. This structure brings high chemical and thermal stability, as well as strongly anisotropic hole mobility along the polar axis. These features, associated with the ability to adjust the transport properties by doping, enable to tune water splitting properties for photoelectrocatalytic H2 evolution and water oxidation. This work then paves the way to a new family of mixed‐anion solids [ABSTRACT FROM AUTHOR]

Published
2023
Full Text
View/download PDF

28. Advanced Functional Hybrid Proton Exchange Membranes Robust and Conductive at 120 °C.

Author

Richard, Jason, Haidar, Fatima, Alzamora, Madeline K., Maréchal, Manuel, Rovira, Natalia, Vacquier, Christophe, Sanchez, Clément, and Laberty-Robert, Christel

Subjects
SILICA fibers, IONOMERS, COMPOSITE membranes (Chemistry), FLUOROPOLYMERS, PETROLEUM as fuel, FUEL cell vehicles, PROTON conductivity
Abstract

Proton-exchange membrane fuel cell vehicles offer a low-carbon alternative to traditional oil fuel vehicles, but their performances still need improvement to be competitive. Raising their operating temperature to 120 °C will enhance their efficiency but is currently unfeasible due to the poor mechanical properties at high temperatures of the state-of-the-art proton-exchange membranes consisting of perfluorosulfonic acid (PFSA) ionomers. To address this issue, xx designed composite membranes made of two networks: a mat of hybrid fibers to maintain the mechanical properties filled with a matrix of PFSA-based ionomer to ensure the proton conductivity. The hybrid fibers obtained by electrospinning are composed of intermixed domains of sulfonated silica and a fluorinated polymer. The inter-fiber porosity is then filled with a PFSA ionomer to obtain dense composite membranes with a controlled fibers-to-ionomer ratio. At 80 °C, these obtained composite membranes show comparable performances to a pure PFSA commercial membrane. At 120 °C however, the tensile strength of the PFSA membrane drastically drop down to 0.2 MPa, while it is maintained at 7.0 MPa for the composite membrane. In addition, the composite membrane shows a good conductivity of up to 0.1 S cm-1 at 120 °C/90% RH, which increases with the ionomer content. [ABSTRACT FROM AUTHOR]

Published
2023
Full Text
View/download PDF

35. The role of Al³⁺‐based aqueous electrolytes in the charge storage mechanism of MnOₓ cathodes

Author

Balland, Véronique, Mateos, Mickaël, Singh, Arvinder, Harris, Kenneth D., Laberty‐Robert, Christel, and Limoges, Benoît

Subjects
conversion mechanism, aluminium ions, MnO2, proton insertion, zinc batteries, aqueous batteries
Abstract

Rechargeable aqueous aluminium batteries are the subject of growing interest, however, the charge storage mechanisms at manganese oxide-based cathodes remain poorly understood. In essense, every study proposes a different mechanism. Here, an in situ spectroelectrochemical methodology is used to unambiguously demonstrate that reversible proton-coupled MnO₂-to-Mn²⁺ conversion is the main charge storage mechanism occurring at MnO₂ cathodes for a range of slightly acidic Al³⁺-based aqueous electrolytes, with the Al³⁺ hexaaquo complex playing the key role of proton donor. In Zn/MnO₂ assemblies, this mechanism is associated with high gravimetric capacities and discharge potentials, up to 560 mAh g⁻¹ and 1.65 V respectively, attractive efficiencies (CE > 99.5% and EE > 82%) and excellent cyclability (almost 100% capacity retention over 1 400 cycles at 2 A g⁻¹). Finally, a critical analysis of the data previously published on MnOₓ cathodes in Al³⁺-based aqueous electrolytes is conducted to conclude on a universal charge storage mechanism, i.e., the reversible electrodissolution/electrodeposition of MnO₂.

Published
2021

41. Self‐Healing: An Emerging Technology for Next‐Generation Smart Batteries.

Author

Narayan, Rekha, Laberty‐Robert, Christel, Pelta, Juan, Tarascon, Jean‐Marie, and Dominko, Robert

Subjects
*STORAGE batteries, *WASTE recycling, *MATERIALS science, *LITHIUM-ion batteries
Abstract

Complex battery degradation is an interplay of different processes correlated to the thermodynamic, chemical, and mechanical instability of materials. Their degradation kinetics and mechanisms are functions of several intrinsic and environmental conditions. The degradation of the battery cell can be minimized by using preventive steps, like artificial interphases, coatings, additives, or materials that operate within the thermodynamic stability voltage window. Like in most systems/applications degradation processes/aging cannot be avoided since battery cells operate in different environments. Self‐healing functionalities have been proved in different areas of material science and they can significantly improve the performance of battery cells. Some of them have been demonstrated on the laboratory scale, while other degradation processes have been tackled only by the development of preventive approaches. Since self‐healing functionalities add additional weight and cost to the battery cell, directions of development should be focused on modification of nonactive materials, preferably based on biosourced materials to lower environmental impact. Important issues include detection of degradation using sensors and the vectorization of self‐healing components and their controlled release. In addition to this, a triggering process of extrinsic self‐healing components together with manufacturability and recyclability should be considered from the early stages of the development phase. [ABSTRACT FROM AUTHOR]

Published
2022
Full Text
View/download PDF

45. Harnessing Cold Sintering to Fabricate Composite Polymer Electrolytes - A Paradigm Shift in Organic-Inorganic Material Assembly

Author

Naboulsi, Agathe, Dussart, Thibaud, Nguyen, Giao T. M., Franger, Sylvain, Fichet, Odile, and Laberty-Robert, Christel

Abstract

The development of composite electrolytes for all-solid-state batteries is an emerging field, but the creation of predominantly inorganic electrolytes remains challenging. In this study, Li6.25Al0.25La3Zr2O12(Al-LLZO), a ceramic material selected for its high ionic conductivity (1 × 10−4S.cm−1at ambient temperature) was shaped by the cold-sintering process (CSP). The organic phase was synthesized by free-radical polymerization of two poly(ethylene oxide) methacrylate derivatives in the presence of lithium bis(trifluoromethanesulfonyl)imide salts (LiTFSI). The polymethacrylate network with dangling poly(ethylene oxide) (PEO) chains was thus obtained. This in situ polymerization allows the one-pot synthesis of the composite electrolyte during CSP. Remarkably, the ionic conductivity of the CSP pellet varied with the nature of the organic phase, ranging from 1 × 10−4to 1 × 10−5S.cm−1for non-grafted and grafted TFSI anion on the PEO-based network, respectively. Additionally, the transport of Li+remained unaffected by the inorganic material’s nature as long as it contained Li species. Furthermore, a significant enhancement of the ionic conductivity was observed in the composite pellet compared to the TFSI grafted network (10−5to 10−7S.cm−1, respectively). Electrochemical impedance spectroscopy measurements revealed changes in the Al-LLZO||PEO-based polymer interface during CSP with the formation of an interphase, confirmed by a low activation energy value (0.1 eV).

Published
2024
Full Text
View/download PDF

46. A first-principles computational comparison of defect-free and disordered, fluorinated anatase TiO 2 (001) interfaces with water

Author

Reeves, Kyle, Dambournet, Damien, Laberty-Robert, Christel, Vuilleumier, Rodolphe, Salanne, Mathieu, PHysicochimie des Electrolytes et Nanosystèmes InterfaciauX (PHENIX), Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-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), Laboratoire de Chimie de la Matière Condensée de Paris (LCMCP), Processus d'Activation Sélective par Transfert d'Energie Uni-électronique ou Radiatif (UMR 8640) (PASTEUR), Département de Chimie - ENS Paris, École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), 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), École normale supérieure - Paris (ENS Paris), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS Paris)

Subjects
[CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry
Abstract

International audience; Chemical doping and other surface modifications have been used to engineer the bulk properties of materials, but their influence on the surface structure and consequently the surface chemistry are often unknown. Previous work has been successful in fluorinating anatase TiO 2 with charge balance achieved via the introduction of Ti vacancies rather than the reduction of Ti. Our work here investigates the interface between this fluorinated titanate with cationic vacancies and a monolayer of water via density functional theory based molecular dynamics. We compute the projected density of states for only those atoms at the interface and for those states that fall within 1 eV of the Fermi level for various steps throughout the simulation, and we determine that the variation in this visualization of the density of states serves as a reasonable tool to anticipate where surfaces are most likely to be reactive. In particular, we conclude that water dissociation at the surface is the main mechanism that influences the anatase (001) surface whereas the change in the density of states at the surface of the fluorinated structure is influenced primarily through the adsorption of water molecules.

Published
2020

47. Hydroxyapatites as Versatile Inorganic Hosts of Unusual Pentavalent Manganese Cations

Author

Varela, Aurea, primary, Gómez-Recio, Isabel, additional, Serrador, Laura, additional, Hernando, María, additional, Matesanz, Emilio, additional, Torres-Pardo, Almudena, additional, Fernández-Díaz, María Teresa, additional, Martínez, Jose L., additional, Gonell, Francisco, additional, Rousse, Gwenaelle, additional, Sanchez, Clément, additional, Laberty-Robert, Christel, additional, Portehault, David, additional, González-Calbet, José M., additional, and Parras, Marina, additional

Published
2020
Full Text
View/download PDF

48. Hydronium Ions Stabilized in a Titanate-Layered Structure with High Ionic Conductivity: Application to Aqueous Proton Batteries

Author

Kang, Seongkoo, primary, Singh, Arvinder, additional, Reeves, Kyle G., additional, Badot, Jean-Claude, additional, Durand-Vidal, Serge, additional, Legein, Christophe, additional, Body, Monique, additional, Dubrunfaut, Olivier, additional, Borkiewicz, Olaf J., additional, Tremblay, Benoît, additional, Laberty-Robert, Christel, additional, and Dambournet, Damien, additional

Published
2020
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results