Synthesis by solid route and physicochemical characterizations of blends of calcium orthophosphate powders and mesoporous silicon particles

The purpose of the study was to investigate the synthesis of economic calcium phosphate powders from recycled oyster shells, using a ball milling method. The oyster shell powder and a calcium pyrophosphate powder were used as starting materials and ball milled, then heat treated at 1,050°C for 5 h to produce calcium phosphate powders through a solid-state reaction. Electrochemically synthesized mesoporous silicon microparticles were then added to the prepared phosphate powders by mechanical mixer. The final powders were characterized using X-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy to analyze their chemical composition and determine the most suitable process conditions. The biocompatibility of the produced powders was also tested in vitro using murine cells and the results showed good biocompatibility

Electron Spin Resonance of Nickelate

International audienceIn the present study we focused on the nickelate system, which presents stable stripe order and allow a large domain of oxygen doping. More specifically, we studied the non-stoichiometric system La2NiO4 in which the oxygen excess tends to order. ESR technique has been used due to its sensibility to microscopic magnetic fluctuations. We present a systematic study of the charge and spin fluctuations in oxygen doped nickelates to get insight into the dynamic of the system using ESR. The intrinsic resonance signal of polycrystalline La2NiO4 - values 0.09 and 0.12 have been studied, in a large temperature range (10K < T < 300 K). The = 0.12 compound has been chosen as a starting point, since neutron diffraction studies in composition very close to this value have been well characterized the stripe order in this system, showing that the holes order at around TCO = 200K, while the spins order at TS = 110K. By analogy, the ESR results on this compound allowed us to interpret the results in the other compound

Co-precipitation synthesis and characterization of tin-doped α-Fe 2 O 3 nanoparticles with enhanced photocatalytic activities

International audienc

Influence of sputtering conditions and annealing parameters on structure and morphology of NiTiO3 ilmenite thin films

International audienc

Effects of synthetic routes on structural, dielectric and electrical properties of CaCu3Ti4O12 ceramics

International audienc

Controlling the magnetoelectric coupling in Ni/BiFe0.95Mn0.05O3 with a dielectric spacer

International audienc

Constructing multiple heterogeneous shell on the CaCu3Ti4O12 core for better dielectric performances

International audienc