A5066133111- Fuel Cells and Related Materials
- Electrocatalysts for Energy Conversion
- Membrane-based Ion Separation Techniques
- Advanced battery technologies research
- Advanced Battery Technologies Research
- Conducting polymers and applications
- Membrane Separation Technologies
- Catalytic Processes in Materials Science
- Hydrogels: synthesis, properties, applications
- Advancements in Solid Oxide Fuel Cells
- Catalysis and Hydrodesulfurization Studies
- Laser Applications in Dentistry and Medicine
- Machine Learning in Materials Science
- Extraction and Separation Processes
- Dental materials and restorations
- Advanced MRI Techniques and Applications
- Electrochemical Analysis and Applications
- Nanomaterials for catalytic reactions
- Membrane Separation and Gas Transport
- NMR spectroscopy and applications
- Microfluidic and Capillary Electrophoresis Applications
- biodegradable polymer synthesis and properties
- Collagen: Extraction and Characterization
- Optical Imaging and Spectroscopy Techniques
- Dyeing and Modifying Textile Fibers
Laboratoire Énergies et Mécanique Théorique et Appliquée
2010-2024
Université de Lorraine
2013-2024
Centre National de la Recherche Scientifique
2011-2024
Université de Montpellier
2003-2012
CEA Grenoble
2010-2011
Structure et Propriétés d'Architectures Moléculaires
2011
Commissariat à l'Énergie Atomique et aux Énergies Alternatives
2010-2011
Institut Nanosciences et Cryogénie
2010-2011
DSM (Netherlands)
2010
Institut Européen des Membranes
2003-2007
Oxygen reduction reaction (ORR) is a key step in many electrochemical devices such as fuel cells and metal-air batteries. However, the proceeds at significant overpotential requiring Pt-based catalysts. The scarcity economical challenges associated with Pt one of major limitations for commercialization devices. In this context, research community constantly exploring other low-cost earth-abundant materials ORR Carbon nanomaterials are identified promising electrocatalysts due to their superb...
Abstract This study examines the effect of pretreatment and doping to enhance ORR activity multiwalled carbon nanotubes (MWCNTs). Melamine thio-urea are chosen as precursors for mono co-doping, respectively. A series samples with pristine pretreated CNTs prepared characterized physicochemically by Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) transmission electron microscopy (TEM) electrochemically cyclic voltammetry (CV) linear sweep (LSV). The obtained results show that...
The coexistence of single atoms and nanoparticles is shown to increase the oxygen reduction performance in Fe-N-C electrocatalysts, but mechanisms underlying this synergistic effect remain elusive. In study, model electrocatalysts with controlled ratios FeN4 sites Fe3C nanoclusters systematically designed synthesized. Experiments density functional theory (DFT) computations reveal that near modulate electron Fe single-atom microenvironment through an withdrawing effect. This substantially...
Small angle neutron scattering experiments were performed on a proton exchange membrane fuel cell in order to determine the transversal water concentration profile, within polymer electrolyte. This is determined under state-of-art operating conditions. From spectra, different profiles deduced and discussed terms of competition between electro-osmosis back diffusion. For steady states, balance these driving forces modified by current density. It also demonstrated that this equilibrium...
Abstract In situ chemical polymerisation of pyrrole in Nafion®‐115 membranes produces a composite material that shows decrease methanol crossover compared with the non‐modified material, and good protonic conduction (area resistance 0.65 Ω cm 2 ). Pyrrole is impregnated from an appropriate solvent, choice oxidising agent (hydrogen peroxide, ammonium peroxodisulfate) provides two types modified membrane. Membrane characterisation using infrared spectroscopy presence oligomers polymer, but...
The fabrication step of the catalyst layer (CL) is important to master in order achieve good performance fuel cells. Nevertheless, final structure a CL depends on many factors, such as ink composition and preparation, well its preparation steps. However, it not easy for neophytes understand relationship between with obtained In this work, systemic experimental study was carried out qualitatively correlate PEMFC by playing different parameters operating conditions. All prepared samples were...
Anion exchange membrane fuel cells (AEMFCs) have recently attracted significant attention as low-cost alternative to traditional proton because of the possible use platinum-group metal-free electrocatalysts. Over past decade, new materials dedicated alkaline medium, such anion membranes (AEMs) and ionomers (AEIs), been developed studied in AEMFCs. However, only a few AEMs AEIs are commercially available, there no ready-to-use electrodes assemblies (MEAs) with desired AEIs. Consequently, need...
Through (1)H NMR relaxometry techniques (determination of the spin-lattice relaxation time as a function measurement frequency), we have investigated, on molecular scale, water behavior in Nafion NRE 212 under acid, sodium, and potassium forms, latter arising from different chemical treatments (with without EDTA). Quantitatively, it turns out that (i) EDTA removes unwanted cations may affect mobility (ii) natural countercations (sodium potassium) also according to their size. In order go...
Abstract The evolution of membrane water concentration profile has been studied by small angle neutron scattering during on/off cycling PEMFC operation with fully humidified air in co‐flow configuration. profiles evolve opposite ways close to the gas inlet and outlet. Whereas global content increases at as fuel cell delivers current, membranes are dried out balance between diffusion from cathode anode electroosmostic drag gives a net flow which is different equilibrium reached less than 15...
The Nafion®117 membrane was modified chemically, using a conducting polymer pyrrole. oxidants ferric chloride (PPy-Fe), hydrogen peroxide (PPy-O) and ammonium persulfate (PPy-S) were used to carry out the polymerization in both aqueous organic media. Nafion® presence of N-méthylformamide increases transport alkali heavy metal cations reduces considerably methanol diffusion electro-osmosis. Therefore, can be successfully electrodialysis electrolyte solutions hydro-organic media may regarded...
Water sorption and desorption in Nafion ® 117 membranes acid form were studied by means of dynamic experiments as a response relative humidity steps. The recorded mass variations with time the membrane samples analyzed least squares method based on model that takes into account an interfacial transfer coefficient between bulk humid gas, diffusion being assumed negligible. In case large steps humidity, predicts kinetics is much faster than sorption. comparisons experimental results for small...