A5007223696- Pickering emulsions and particle stabilization
- Material Dynamics and Properties
- Surfactants and Colloidal Systems
- Rheology and Fluid Dynamics Studies
- Fluid Dynamics and Heat Transfer
- Proteins in Food Systems
- Polysaccharides Composition and Applications
- Liquid Crystal Research Advancements
- Adsorption, diffusion, and thermodynamic properties of materials
- Surface Modification and Superhydrophobicity
- Plant Surface Properties and Treatments
- Theoretical and Computational Physics
- Micro and Nano Robotics
- Food composition and properties
- Force Microscopy Techniques and Applications
- Polymer Surface Interaction Studies
- Minerals Flotation and Separation Techniques
- Lipid Membrane Structure and Behavior
- Fluid Dynamics Simulations and Interactions
- Mesoporous Materials and Catalysis
- Hydrogels: synthesis, properties, applications
- Advanced Theoretical and Applied Studies in Material Sciences and Geometry
- Polymer crystallization and properties
- Electrostatics and Colloid Interactions
- Nanomaterials and Printing Technologies
Université de Montpellier
2016-2025
Laboratoire Charles Coulomb
2016-2025
Chimie Moléculaire, Macromoléculaire, Matériaux
2021-2025
Centre National de la Recherche Scientifique
2015-2024
Institut Universitaire de France
2023
FORTH Institute of Electronic Structure and Laser
2021
University of Crete
2021
Instituto de Pesquisas Tecnológicas
2015
Laboratoire de Chimie Physique
2005-2009
Institut Européen des Membranes
2005-2009
We investigate the spreading of falling ambient-temperature Newtonian drops after their normal impact on a quartz plate covered with thin layer liquid nitrogen. As drop expands, nitrogen evaporates, generating vapour film that maintains in levitation. Consequently, latter spreads inverse Leidenfrost conditions. Three drop-spreading regimes are observed: (i) inertio-capillary, (ii) inertio-viscous, and (iii) inertio-viscous-capillary. In first regime, although expansion is essentially driven...
We use conventional and multispeckle dynamic light scattering to investigate the dynamics of a wide variety jammed soft materials, including colloidal gels, concentrated emulsions, surfactant phases. For all systems, structure factor f(q,t) exhibits two-step decay. The initial decay is due thermally activated diffusive motion scatterers, as indicated by q−2 dependence characteristic relaxation time, where q vector. However, constrained scatterers in are arrested terminates plateau....
Measuring, characterizing and modelling the slow dynamics of glassy soft matter is a great challenge, with an impact that ranges from industrial applications to fundamental issues in modern statistical physics, such as glass transition description out-of-equilibrium systems. Although our understanding these phenomena still far complete, recent simulations novel theoretical approaches experimental methods have shed new light on materials. In this paper, we review work last few years, emphasis...
Dispersions of colloidal particles in cholesteric liquid crystals form an unusual solid by stabilizing a network linear defects under tension the ideal layered structure cholesteric. The large length scales allowed direct observation structure, and its properties were correlated with rheological measurements elasticity. This system serves as model for class solids formed when are mixed materials such thermotropic lyotropic smectic block copolymers.
Bimetallic Pd−Au nanostructures were synthesized in the soft templates provided by surfactant hexagonal mesophases. The are constituted a core rich gold and Pd porous shell. electrocatalytic activity of these for ethanol oxidation basic medium was compared with that alloyed nanoparticles solution. alloy is active toward an alkaline but not durable realizing this process. Pdshell−Aucore mesophases promising application direct fuel cells as they exhibit very good high stability.
Palladium nanowires (of length a few tens of nanometers) are synthesized in hexagonal mesophase formed by quaternary system (Pd-doped water, surfactant, cosurfactant, and oil) electron beam irradiation. The mesophases can be doped high concentrations palladium (0.1 M) without any disturbance the structure which allows quantitative synthesis 1D Pd nanostructures. We found an increase average with amount cosurfactant (pentanol) that assists reduction/growth processes. electrocatalytic...
Abstract The development of visible-light responsive photocatalysts would permit more efficient use solar energy and thus bring sustainable solutions to many environmental issues. Conductive polymers appear as a new class very active under visible light. Among them poly(3,4-ethylenedioxythiophene) (PEDOT) is one the most promising conjugated polymer with wide range applications. PEDOT nanostructures synthesized in soft templates via chemical oxidative polymerization demonstrate unprecedented...
We use linear rheology and multispeckle dynamic light scattering (MDLS) to investigate the aging of a gel composed multilamellar vesicles. Light data indicate rearrangement through an unusual ultraslow ballistic motion. A dramatic slowdown dynamics with sample age t(w) is observed for both MDLS, characteristic relaxation time scaling as t(mu)w. find same exponent mu = 0.78 techniques, suggesting that they probe similar physical processes, applied or internal stresses respectively. simple...
A positively charged, mixed bilayer vesicle in the presence of negatively charged surfaces (for example, colloidal particles) can spontaneously partition into an adhesion zone definite area and another that repels additional negative objects. Although membrane itself has nonnegative charge repulsive zone, counterions on interior aggregate there present a net to exterior. Beyond fundamental result oppositely objects repel, this mechanism helps explain recent experiments surfactant vesicles.
In the presence of condensing agents such as nonadsorbing polymer, multivalent counter ions, and specific bundling proteins, chiral biopolymers typically form bundles with a finite thickness, rather than phase-separating into polymer-rich phase. Although short-range repulsive interactions or geometrical frustrations are thought to force equilibrium bundle size be limited, precise mechanism is yet resolved. The importance tight control biopolymer illustrated by ubiquitous cytoskeletal actin...
Ultrathin palladium hexagonal nanosheets were synthesized in emulsions constituted of droplets toluene containing Pd complexes water and stabilized by CTAB as surfactant quaternary mesophases formed water, complexes, CTAB, a cosurfactant. We have identified slow reduction nucleation provided CO adsorption at the interface key factors for formation nanosheets. These exhibit broad absorption band from visible to near-infrared region.
Anisotropic conducting PEDOT polymers are prepared within hexagonal mesophases according to an original one-pot synthesis and characterized after extraction.
Conjugated polymer polypyrrole nanostructures modified with bimetallic (Pt–Ni) nanoparticles are very active for hydrogen generation and a synergetic effect is obtained by alloying Pt Ni.
Significance The sudden, catastrophic failure of materials under a constant mechanical load is widespread, occurring from geological scales, as in earthquakes, to biological and soft-matter systems, protein, polymer, colloidal gels. Failure often preceded by long induction time, with little if any macroscopic signs weakening, making it unpredictable. Here, we investigate the model gel load, measuring simultaneously its response microscopic dynamics. We show that undergoes burst plastic...
Power law rheology is of widespread occurrence in complex materials that are characterized by the presence a very broad range microstructural length and time scales. Although phenomenological models able to reproduce observed rheological features exist, general well-established connection with microscopic origin this mechanical behavior still missing. As model system, work focuses on fractal colloidal gel. We thoroughly characterize linear power sample its age dependence. show at all ages...
Colloidal particles can form unexpected two-dimensional ordered colloidal crystals when they interact with surfactants of the opposite charge. Coulomb interactions lead to self-limited adsorption on surface vesicles formed by surfactants. The adsorbed but fluid rafts vesicle surfaces, and these ultimately robust crystals. This use attractive interaction between surfactant structures offers a potential new route self-assembly structures.
We use time-resolved x-ray photon correlation spectroscopy to investigate the slow dynamics of colloidal gels made moderately attractive carbon black particles. show that is temporally heterogeneous and quantify its fluctuations by measuring variance chi instantaneous intensity function. The amplitude dynamical has a nonmonotonic dependence on scattering vector q, in stark contrast with recent experiments strongly [Duri Cipelletti, Europhys. Lett. 76, 972 (2006)]. propose simple scaling...
Abstract Soft materials are usually defined as made of mesoscopic entities, often self-organised, sensitive to thermal fluctuations and weak perturbations. Archetypal examples colloids, polymers, amphiphiles, liquid crystals, foams. The importance soft in everyday commodity products, well technological applications, is enormous, controlling or improving their properties the focus many efforts. From a fundamental perspective, possibility manipulating material properties, by tuning...