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Scandium oxides nanopowders have been synthesized using a sol-gel route. ScOOH nanoparticles have been first prepared in solution using ScCl3, xH2O as precursor. Influence of pH and reflux time on particles size and shape has been studied. Sc2O3 nanoparticles were then obtained after ScOOH sol drying. Sols were characterized by laser granulometry, thermogravimetry and differential analysis (TGA- DSC). Depending on pH, 40 to 1000 nm size ScOOH particles can be obtained. At a given pH, the reflux time duration also influences the ScOOH particles size. The ScOOH sol can be used to prepare highly pure Sc2O3 nanopowders. X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR) and Transmission Electron Microcopy (TEM), were used to characterize Sc203 nanopowders obtained from the various ScOOH solutions. The DSC and laser granulometry data indicate a strong relation between the nanoparticles size and the temperature of transformation of g-ScOOH to Sc2O3. Depending on the sol preparation various particles Sc2O3 size can then be obtained allowing the selection of the more suitable powder for transparent ceramic preparation.

Scandium oxides nanopowders have been synthesized using a sol-gel route. ScOOH nanoparticles have been first prepared in solution using ScCl3, xH2O as precursor. Influence of pH and reflux time on particles size and shape has been studied. Sc2O3 nanoparticles were then obtained after ScOOH sol drying. Sols were characterized by laser granulometry, thermogravimetry and differential analysis (TGA- DSC). Depending on pH, 40 to 1000 nm size ScOOH particles can be obtained. At a given pH, the reflux time duration also influences the ScOOH particles size. The ScOOH sol can be used to prepare highly pure Sc2O3 nanopowders. X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR) and Transmission Electron Microcopy (TEM), were used to characterize Sc203 nanopowders obtained from the various ScOOH solutions. The DSC and laser granulometry data indicate a strong relation between the nanoparticles size and the temperature of transformation of g-ScOOH to Sc2O3. Depending on the sol preparation various particles Sc2O3 size can then be obtained allowing the selection of the more suitable powder for transparent ceramic preparation.

Several approaches based on the sol-gel process have been developed to synthesize YSZ (ZrO2-8%Y2O3) films with controlled porosities and thickness. Thick monolayer (> 10 µm) was obtained from a powder charged polymeric sol using the dip-coating process. This film exhibited porosities after a heat treatment at 1300{degree sign}C during 4 hours in air. These porosities are related to the decomposition of carbonate species formed during the heat-treatment. Dense films with a thickness ranging from 1 to 5 μm were synthesized via the deposition (spin-coating and dip-coating) of a solution containing YSZ nanoparticles. The calcinations temperature influences the films' density and porosity. YSZ films were synthesized on anode support (Ni-YSZ/YSZ) in order to evaluate the microstructure of these films in real fuel cell.