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2. Epoxy-based multifunctional solid polymer electrolytes for structural batteries and supercapacitors. a short review.

Author

Adak, Nitai Chandra, Sungmook Lim, Guk-Hwan Lee, Wonoh Lee, Zheng-Ze Pan, and Maréchal, Manuel

Subjects
ELECTROLYTES, SUPERCAPACITORS, IONIC conductivity, THERMAL stability, ELECTROCHEMICAL analysis
Abstract

The potential applications of epoxy-based solid polymer electrolytes are continually expanding because of their versatile characteristics. These characteristics include mechanical rigidity, nonvolatility, nonflammability, and electrochemical stability. However, it is worth noting that pure epoxy-based solid polymer electrolytes inherently exhibit lower ion transport capabilities when compared to traditional liquid electrolytes. Striking a balance between high mechanical integrity and superior ionic conductivity at room temperature poses a significant challenge. In light of this challenge, this review is dedicated to elucidating the fundamental concepts of epoxy-based solid polymer electrolytes. It will explore various preparation techniques, the incorporation of different nanomaterials into epoxy-based solid polymer electrolytes, and an evaluation of their multifunctional properties. This comprehensive evaluation will cover both mechanical and electrical properties with a specific focus on their potential applications in batteries and structural supercapacitors. [ABSTRACT FROM AUTHOR]

Published
2024
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8. 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
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18. Operando Raman Spectroscopy and Synchrotron X-ray Diffraction of Lithiation/Delithiation in Silicon Nanoparticle Anodes

Author

Tardif, Samuel, primary, Pavlenko, Ekaterina, additional, Quazuguel, Lucille, additional, Boniface, Maxime, additional, Maréchal, Manuel, additional, Micha, Jean-Sébastien, additional, Gonon, Laurent, additional, Mareau, Vincent, additional, Gebel, Gérard, additional, Bayle-Guillemaud, Pascale, additional, Rieutord, François, additional, and Lyonnard, Sandrine, additional

Published
2017
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20. One−pot Route To Class II Hybrid Ionogels Electrolytes

Author

Fontaine, Olivier, Touidjine, Amina, Maréchal, Manuel, Bonhomme, Christian, Ribot, François, Geffroy, Bernard, Jousselme, Bruno, Sanchez, Clément, Laberty-Robert, Christel, Chaire Chimie des matériaux hybrides, Laboratoire de Chimie de la Matière Condensée de Paris (LCMCP), Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Electrochimie et de Physico-chimie des Matériaux et des Interfaces (LEPMI ), Institut de Chimie du CNRS (INC)-Institut National Polytechnique de Grenoble (INPG)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Université Joseph Fourier - Grenoble 1 (UJF)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Laboratoire de physique des interfaces et des couches minces [Palaiseau] (LPICM), École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Chimie des Surfaces et Interfaces (LCSI), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), and Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National Polytechnique de Grenoble (INPG)-Institut de Chimie du CNRS (INC)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)

Subjects
[CHIM.MATE]Chemical Sciences/Material chemistry
Abstract

International audience; A new system based on class II hybrid ionogels (Si-IL gels) has been developed for overcoming leaking problems associated with liquid electrolytes in dye-sensitized solar cells (DSSCs). We co-condensed a silica precursor with an alkoxysilane functionalized ionic liquid precursor, under acidic conditions, to obtain a hybrid ionogel where ionic liquid is covalently linked to silica domains. The morphology and the microstructure of the Si-IL xerogels were explored using NMR, SAXS and field emission scanning electron microscopy (FE-SEM). Cyclic voltammetry experiments were carried out to measure the apparent diffusion coefficient of the redox couple I−/I3− into these Si-IL gels. The diffusion coefficient of triiodide in the gel is comparable to the one observed in a solvent-free based ionic liquid electrolyte. These Si-IL gels were evaluated as electrolytes in quasi-solid-state DSSCs. For this purpose, various DSSCs have been fabricated. The cells containing Si-IL ionogels with 50 wt% of a silica modified liquid ionic precursor exhibit a short-circuit photocurrent of 2.8 mA cm−2, an open circuit voltage of 680 mV, a fill factor of 0.65, and an overall efficiency of 1.25%. Accordingly, this work constitutes a proof of concept.

Published
2014
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24. A one-pot route to prepare class II hybrid ionogel electrolytes

Author

Fontaine, Olivier, primary, Touidjine, Amina, additional, Maréchal, Manuel, additional, Bonhomme, Christian, additional, Ribot, François, additional, Geffroy, Bernard, additional, Jousselme, Bruno, additional, Sanchez, Clément, additional, and Laberty-Robert, Christel, additional

Published
2014
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28. OperandoRaman Spectroscopy and Synchrotron X-ray Diffraction of Lithiation/Delithiation in Silicon Nanoparticle Anodes

Author

Tardif, Samuel, Pavlenko, Ekaterina, Quazuguel, Lucille, Boniface, Maxime, Maréchal, Manuel, Micha, Jean-Sébastien, Gonon, Laurent, Mareau, Vincent, Gebel, Gérard, Bayle-Guillemaud, Pascale, Rieutord, François, and Lyonnard, Sandrine

Abstract

OperandoRaman spectroscopy and synchrotron X-ray diffraction were combined to probe the evolution of strain in Li-ion battery anodes made of crystalline silicon nanoparticles. The internal structure of the nanoparticles during two discharge/charge cycles was evaluated by analyzing the intensity and position of Si diffraction peaks and Raman TO–LO phonons. Lithiation/delithiation of the silicon under limited capacity conditions triggers the formation of “crystalline core–amorphous shell” particles, which we evidenced as a stepwise decrease in core size, as well as sequences of compressive/tensile strain due to the stress applied by the shell. In particular, we showed that different sequences occur in the first and the second cycle, due to different lithiation processes. We further evidenced critical experimental conditions for accurate operandoRaman spectroscopy measurements due to the different heat conductivity of lithiated and delithiated Si. Values of the stress extracted from both operandoXRD and Raman are in excellent agreement. Long-term ex situmeasurements confirmed the continuous increase of the internal compressive strain, unfavorable to the Si lithiation and contributing to the capacity fading. Finally, a simple mechanical model was used to estimate the sub-nanometer thickness of the interfacial shell applying the stress on the crystalline core. Our complete operandodiagnosis of the strain and stress in SiNPs provides both a detailed scenario of the mechanical consequences of lithiation/delithiation in SiNP and also experimental values that are much needed for the benchmarking of theoretical models and for the further rational design of SiNP-based electrodes.

Published
2017
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31. Proton Transport in Electrospun Hybrid Organic-Inorganic Membranes: An Illuminating Paradox.

Author

Santos, Leslie Dos, Maréchal, Manuel, Guillermo, Armel, Lyonnard, Sandrine, Moldovan, Simona, Ersen, Ovidiu, Sel, Ozlem, Perrot, Hubert, and Laberty‐Robert, Christel

Subjects
*PROTONS, *ELECTRON transport, *ELECTROSPINNING, *PROTON exchange membrane fuel cells, *NANOSTRUCTURED materials, *IMPEDANCE spectroscopy
Abstract

Chemistry and processing have to be judiciously combined to structure the membranes at various length scales to achieve efficient properties for polymer electrolyte membrane fuel cell to make it competitive for transport. Characterizing the proton transport at various length and space scales and understanding the interplays between the nanostructuration, the confinement effect, the interactions, and connectivity are consequently needed. The goal here is to study the proton transport in multiscale, electrospun hybrid membranes (EHMs) at length scales ranging from molecular to macroscopic by using complementary techniques, i.e., electrochemical impedance spectroscopy, pulsed field gradient-NMR spectroscopy, and quasielastic neutron scattering. Highly conductive hybrid membranes (EHMs) are produced and their performances are rationalized taken into account the balances existing between local interaction driven mobility and large-scale connectivity effects. It is found that the water diffusion coefficient can be locally decreased (2 × 10−6 cm2 s−1) due to weak interactions with the silica network, but the macroscopic diffusion coefficient is still high (9.6 × 10−6 cm2 s−1). These results highlight that EHMs have slow dynamics at the local scale without being detrimental for long-range proton transport. This is possible through the nanostructuration of the membranes, controlled via processing and chemistry. [ABSTRACT FROM AUTHOR]

Published
2016
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32. The role of the ionic liquid C6C1ImTFSI in the sol–gel synthesis of silica studied using in situ SAXS and Raman spectroscopy.

Author

Nayeri, Moheb, Nygård, Kim, Karlsson, Maths, Maréchal, Manuel, Burghammer, Manfred, Reynolds, Michael, and Martinelli, Anna

Abstract

The sol–gel synthesis of a silica based ionogel using the ionic liquid 1-hexyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide (C6C1ImTFSI) as the solvent has been followed in situ by combined μ-focused X-ray scattering and μ-Raman spectroscopy. By covering the momentum transfer range 0.2 ＜ q ＜ 30 nm−1 we probe the evolution of the characteristic peaks of the ionic liquid, associated with the existence of polar and non-polar domains, as a function of reaction time. Our detailed analysis of the small angle X-ray scattered (SAXS) pattern reveals that the nano-structure of the ionic liquid is partially retained during the sol–gel synthesis, as indicated by the broader yet distinguishable SAXS signatures. We also observe that the signature associated with the non-polar and polar domains shift to higher and lower q-values, respectively. Interestingly, this behavior correlates with the evolution of the chemical composition of the sol as probed by Raman spectroscopy. More precisely, we observe that both the nano-structural changes and the production of polar molecules arrest at the point of gelation. This is rationalized by the tendency of the reagents and products of the sol–gel reaction to locate in different portions of the nano-structure of the ionic liquid. [ABSTRACT FROM AUTHOR]

Published
2015
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33. Layer-by-Layer Characterization of a Model Biofuel Cell Anode by (in Situ) Vibrational Spectroscopy

Author

Fan, Meikun, Maréchal, Manuel, Finn, Amanda, Harrington, David A., and Brolo, Alexandre G.

Abstract

Polarization modulation infrared reflection absorption spectroscopy (PM-IRRAS) and (in situ) surface-enhanced (resonant) Raman scattering (SE(R)RS) were used as “quality control” tools during the construction of a model biofuel cell anode. The model anode was a layered structure formed by 4-hydroxythiophenol (HTP) attached to a coenzyme analog, cibacron blue F3G-A (CB), which then supported the adsorption of the enzyme formaldehyde dehydrogenase (FalDH). Ex situ SERS and PM-IRRAS showed the HTP attached to a gold surface through its thiol group. The covalent binding of CB to the HTP layer was confirmed by a combination of ex situ and in situ SERS data. In situ SERS spectra after adsorption of FalDH to the CB layer confirmed successful enzyme immobilization.

Published
2011
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34. Proton transport through acid aggregates in a hydrated precise sulfophenylated polyethylene

Author

Benjamin Paren, Lionel Picard, Patrice Rannou, Manuel Maréchal, William Neary, Aaron Kendrick, Kennemur, Justin G., Amalie Frischknecht, Karen Winey, CEA-DRT/LITEN/DEHT/STB, Synthèse, Structure et Propriétés de Matériaux Fonctionnels (STEP), SYstèmes Moléculaires et nanoMatériaux pour l’Energie et la Santé (SYMMES), Institut de Chimie du CNRS (INC)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS), Département Interfaces pour l'énergie, la Santé et l'Environnement (DIESE), Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), University of Pennsylvania [Philadelphia], Maréchal, Manuel, Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), and University of Pennsylvania

Subjects
[CHIM] Chemical Sciences, [CHIM]Chemical Sciences, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2019

35. Ion transport and aggregate morphology in precise sulfophenylated polyethylene ionomers

Author

Benjamin Paren, Lionel Picard, Patrice Rannou, Manuel Maréchal, William Neary, Aaron Kendrick, Kennemur, Justin G., Amalie Frischknecht, Karen Winey, CEA-DRT/LITEN/DEHT/STB, Synthèse, Structure et Propriétés de Matériaux Fonctionnels (STEP), SYstèmes Moléculaires et nanoMatériaux pour l’Energie et la Santé (SYMMES), Institut de Chimie du CNRS (INC)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS), Département Interfaces pour l'énergie, la Santé et l'Environnement (DIESE), Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), University of Pennsylvania [Philadelphia], Maréchal, Manuel, Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), and University of Pennsylvania

Subjects
[CHIM] Chemical Sciences, [CHIM]Chemical Sciences, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2019

36. Thermodynamics of Binary and Ternary Polymer Blend Nanocomposites

Author

Shawn Maguire, Krook, Nadia M., Patrice Rannou, Manuel Maréchal, Kohji Ohno, Kristen Brosnan, Composto, Russell J., Synthèse, Structure et Propriétés de Matériaux Fonctionnels (STEP), SYstèmes Moléculaires et nanoMatériaux pour l’Energie et la Santé (SYMMES), Institut de Chimie du CNRS (INC)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS), Département Interfaces pour l'énergie, la Santé et l'Environnement (DIESE), Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Institute for Chemical Research, Kyoto University (KUICR), University of Pennsylvania [Philadelphia], Maréchal, Manuel, Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), and University of Pennsylvania

Subjects
[CHIM] Chemical Sciences, [CHIM]Chemical Sciences, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2019

37. Proton Transport within Acid Aggregates in a Hydrated Precise Sulfophenylated Polyethylene

Author

Benjamin Paren, Lionel Picard, Patrice Rannou, Manuel Marechal, William Neary, Aaron Kendrick, Justin Kennemur, Amalie L. Frischknecht, Karen Winey, CEA-DRT/LITEN/DEHT/STB, Synthèse, Structure et Propriétés de Matériaux Fonctionnels (STEP), SYstèmes Moléculaires et nanoMatériaux pour l’Energie et la Santé (SYMMES), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Département Interfaces pour l'énergie, la Santé et l'Environnement (DIESE), Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), University of Pennsylvania, Institut de Chimie du CNRS (INC)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS), University of Pennsylvania [Philadelphia], and Maréchal, Manuel

Subjects
[CHIM] Chemical Sciences, [CHIM]Chemical Sciences, ComputingMilieux_MISCELLANEOUS
Abstract

Hydrated acid aggregates in a precise sulfophenylated polyethylene exhibit high proton conductivity. This study focuses on a new precise polymer synthesized by ring-opening polymerization, p5PhSA, that has a polyethylene backbone with a sulfonated phenyl group pendant on every 5th carbon. The structure of p5PhSA is characterized with X-ray scattering and the proton conductivity is measured by electrical impedance spectroscopy. Experiments are performed as a function of relative humidity and temperature. Water uptake in p5PhSA is determined by sorption measurements as a function of humidity. Atomistic molecular dynamics simulations are used to elucidate the structure of the acid aggregates in the amorphous polymer matrix and are directly compared to absolute X-ray scattering data. At 40°C and 90% relative humidity, the proton conductivity of p5PhSA is 0.23 S/cm, exceeding that of Nafion at the same conditions. At room temperature, the interaggregate distance nearly doubles from 1.8 nm at 0% relative humidity to 3.4 nm at 100% relative humidity. The swelling of these acid aggregates with water is reversible and facilitates the proton transport through p5PhSA. Figure 1

Published
2019
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38. Proton Diffusion Coefficient in Electrospun Hybrid Membranes by Electrochemical Impedance Spectroscopy.

Author

Dos Santos L, Laberty-Robert C, Maréchal M, Perrot H, and Sel O

Abstract

Electrochemical Impedance Spectroscopy (EIS) was, for the first time, used to estimate the global transverse proton diffusion coefficient, D(H+)(EHM), in electrospun hybrid conducting membranes (EHMs). In contrast to conventional impedance spectroscopy, EIS measurements were performed at room temperature with a liquid interface. In this configuration, the measure of the bulk proton transport is influenced by the kinetics of the transfer of proton at the solid/liquid interface. We demonstrated that the use of additives in the process of the membrane impacts the organization of the hydrophilic domains and also the proton transport. The D(H+)(EHM) is close to 1.10(-7) cm(2) s(-1) (± 0.1.10(-7) cm(2) s(-1)) for the EHMs without additive, whereas it is 4.10(-6) cm(2) s(-1) (± 0.4.10(-6) cm(2) s(-1)) for EHMs with additives.

Published
2015
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39. Sulfonic and phosphonic acid and bifunctional organic-inorganic hybrid membranes and their proton conduction properties.

Author

Sel O, Azais T, Maréchal M, Gébel G, Laberty-Robert C, and Sanchez C

Abstract

Hybrid organic-inorganic approaches are used for the synthesis of bifunctional proton exchange membrane fuel cell (PEMFC) membranes owing to their ability to combine the properties of a functionalized inorganic network and an organic thermostable polymer. We report the synthesis of both sulfonic and phosphonic acid functionalized mesostructured silica networks into a poly(vinylidenefluoride-co-hexafluoropropylene) (poly(VDF-co-HFP) copolymer. These membranes, containing different amounts of phosphonic acid and sulfonic acid groups, have been characterized using FTIR and NMR spectroscopy, SA-XRD, SAXS, and electrochemical techniques. The proton conductivity of the bifunctional hybrid membranes depends strongly on hydration, increasing by two orders of magnitude over the relative humidity (RH) range of 20 to 100%, up to a maximum of 0.031 S cm(-1) at 60 °C and 100% RH. This value is interesting as only half of the membrane conducts protons. This approach allows the synthesis of a porous SiO(2) network with two different functions, having -SO(3)H and -PO(3)H(2) embedded in a thermostable polymer matrix., (Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Published
2011
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