Lattice parameter, defect concentration and oxygen diffusion in ceria solid solutions
نویسندگان
چکیده
The results of x-ray diffraction, the size of lattice parameter, and the values of oxygen diffusion coefficient in YOu-Ce02 , Gd0u-Ce02 , and Nd01.5-Ce02 systems were reviewed. In YOu-Ce02 system, the lattice parameter decreases as the concentration of YOu increases. In Gd0u-Ce02 system, the lattice parameter does not change very much. And in Nd0u-Ce02 system, it increases as the concentration of NdOu increases. When the oxygen diffusion coefficient was plotted as a function of lattice parameter, there was no correlation between them. However, when the oxygen diffusion coefficient was plotted as a function of the concentration of trivalent cation additives, there was very good correlation between them. Consequently, the diffusion coefficient does not depend on the size of crystal lattice in ceria solid solutions, but it depends on the concentration of trivalent cation additives.
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