A5023667845- Catalytic Processes in Materials Science
- Electronic and Structural Properties of Oxides
- Magnetic Properties and Synthesis of Ferrites
- Semiconductor materials and devices
- Magnetic properties of thin films
- Gas Sensing Nanomaterials and Sensors
- Nanowire Synthesis and Applications
- Multiferroics and related materials
- Magnetic and transport properties of perovskites and related materials
- Catalysis and Oxidation Reactions
- Iron oxide chemistry and applications
- Transition Metal Oxide Nanomaterials
- Advanced Materials Characterization Techniques
- Copper-based nanomaterials and applications
- nanoparticles nucleation surface interactions
- ZnO doping and properties
- Surface and Thin Film Phenomena
- Luminescence Properties of Advanced Materials
- Theoretical and Computational Physics
- Ferroelectric and Piezoelectric Materials
- Advancements in Solid Oxide Fuel Cells
- Metallurgical and Alloy Processes
- Asphalt Pavement Performance Evaluation
- Advanced Condensed Matter Physics
- Microwave Dielectric Ceramics Synthesis
Université de Toulon
2013-2023
Centre National de la Recherche Scientifique
2012-2023
Institut des Matériaux, de Microélectronique et des Nanosciences de Provence
2011-2023
Aix-Marseille Université
2022-2023
L.Garde (United States)
2016
Ehlers-Danlos Society
2015
Universidade Federal de Santa Catarina
2015
Contextual Change (United States)
2015
Secretaria do Meio Ambiente
2015
University of Coimbra
2013
The intermediate steps of the phase transition between metastable monoclinic ${\mathrm{VO}}_{2}(B)$ and stable tetragonal rutile ${\mathrm{VO}}_{2}(R)$ have been studied by in situ electron microscopy. A crystallographic interpretation based on static concentration waves theory is proposed: as temperature increases, long-range order complex lost gradually a first ill crystallized with drastically reduced symmetry formed evidenced from diffraction patterns. Next, new generated that...
The results of a comparative investigation structural and transport properties equiatomic NiPt CoPt phases, in their ordered disordered states, are presented discussed. two compounds display the same kind order-disorder transformation L10 to A1 paramagnetic state. In this study, attention was paid make measurements on samples well defined thermodynamic states which can be either equilibrium or quenched ones. This shows that atomic disorder generated by thermal effect constitutional defects...
Abstract Two porous titanium implants with a pore size diameter of 800 and 1200 μm (Ti800 Ti1200) an interconnected network were manufactured using rapid prototyping. Their dimensions structure matched those the computer assisted design. The porosity was around 60%. compressive strength Young's modulus 80 MPa 2.7 GPa, respectively. These values are comparable to cortical bone. implanted bilaterally in femoral epiphysis 15 New Zealand White rabbits. After 3 8 weeks, abundant bone formation...
We report the Au catalyst-assisted synthesis of 20 μm long GaAs nanowires by vapor-liquid-solid hydride vapor phase epitaxy (HVPE) exhibiting a polytypism-free zincblende for record radii lower than 15 nm down to 5 nm. HVPE makes use GaCl gaseous growth precursors at high mass input which fast dechlorination usual process temperature 715 °C results in planar rate (standard 30-40 μm/h). When it comes nanowires, solidification higher 100 μm/h is observed. Nanowire only proceeds introduction...
The interplay between magnetic properties and chemical ordering in the Co1-xPtx system is investigated theoretically experimentally. Experimental results for Curie temperature, magnetisation paramagnetic susceptibility ordered disordered states are discussed within framework of statistical models. authors show that moments on Pt atoms depend sensitively local environment. A complete equilibrium phase diagram also calculated compared with experimental data.
Abstract Conventional and high resolution electron microscopy have been used to investigate the L12-L10, two-phase mixtures in Co-Pt system. The domain of coexistence phases L12 (Copt3) L10 (Copt) has determined. Three different processes formation two phase mixture from temperature disordered state (A1) studied as a function aging temperature: (1) A1 → + L12, (2) L1 0 (3) L12. In final state, microstructures present same main topologies. Processes involve steps, first one consists ordering...
We report the first synthesis of GaAs nanowires (NWs) by Au-assisted vapor−liquid−solid (VLS) growth in novel hydride vapor phase epitaxy (HVPE) environment. Forty micrometer long rodlike ⟨111⟩ monocrystalline exhibiting a cubic zinc blende structure were grown 15 min with mean density 106 cm−2. The such figures short duration could be explained physics near-equilibrium HVPE. VLS−HVPE is mainly based on solidification after direct and continuous feeding arsenious GaCl precursors through...
Two-dimensional nanoplatelets of WO<sub>3</sub> were synthesized at room temperature. The large exposed (020) facets the show a high catalytic activities, for CO conversion and photodegradation organic pollutant.
The incorporation of Si into vapor-liquid-solid GaAs nanowires often leads to p-type doping, whereas it is routinely used as an n-dopant planar layers. This property limits the applications in electronic and optoelectronic devices. strong amphoteric behavior not yet fully understood. Here, we present first attempt quantify this a function droplet composition temperature. It shown that doping type critically depends on As/Ga ratio droplet. In sharp contrast vapor-solid growth, contains very...
A study of the order-disorder L12 to A1 transformation near a congruent point Co-Pt phase diagram is presented. This work was performed by combining in situ transmission electron microscopy observations, resistivity measurements carried out conditions thermodynamic equilibrium and high-resolution imaging on quenched samples. Resistivity display three characteristic temperatures: 994 K, 1020 K 1032 K. The evolution microstructure with temperature at different heating rates followed dark field...
The interplay between magnetic properties and chemical ordering in the Co1-xPtx system is investigated theoretically experimentally. Experimental results for Curie temperature, magnetisation paramagnetic susceptibility ordered disordered states are discussed within framework of statistical models. authors show that moments on Pt atoms depend sensitively local environment. A complete equilibrium phase diagram also calculated compared with experimental data.
In situ transmission electron microscopy experiments coupled with resistivity measurements have been performed on CoPt3. The antiphase boundaries separating different L12 (Cu3Au-type) ordered domains are shown to be progressively wetted by the disordered phase when approaching critical order-disorder transition from below. This is in excellent qualitative agreement previous cluster variation method calculations Kikuchi and Cahn.
Despite the unavoidable presence of silicon atoms in catalyst alloy droplets during vapor–liquid–solid growth III–V nanowires on substrates, it remains unknown how nucleation is affected by these foreign atoms. In this work, we present first attempt to quantify nanowire rate versus concentration droplet. We calculate chemical potential difference per Ga–As pair quaternary Au–Ga–As–Si liquid droplet and solid state, compare ternary Au–Ga–As without silicon. This allows us compute rates GaAs...