V. B. Vykhodets, T. E. Kurennykh, O. A. Nefedova

APPLICATION OF NUCLEAR REACTION ANALYSIS TO STUDYING HYDROGEN DIFFUSION AND NONSTOICHIOMETRY IN METAL OXIDES

Nuclear reaction analysis is used to investigate hydrogen and oxygen subsystems for the oxides TiO₂, La_0,9Sr_0,1ScO_3-δ and ZrO₂ (10 % Y₂O₃). For comparison, data on deuterium diffusion in Ni are obtained. It is found that the boundary conditions of the diffusion problem for the metal differ greatly from those for the oxides. The general and partial solutions to the diffusion problem have been obtained for this technique. It is shown that, for metals, the experimental data correspond to the condition of the zero flow of deuterium atoms through the irradiated surface, whereas for oxides, these data correspond to the zero concentration of deuterium on the surface. It is found that the atomic surface layer of nanoparticles of titanium dioxide and yttrium-doped zirconium dioxide lacks oxygen in comparison with stoichiometry. Nanopowder synthesis is performed by laser evaporation of a ceramic target. The injection of the D₂O vapor into the working chamber does not lead to the doping of nanoparticles with deuterium and the elimination of oxygen deficiency.

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