PHASE EQUILIBRIA IN THE YO-SnO SYSTEM

A series of samples in the YO-SnO system with different ratios of yttrium and tin oxides were obtained by solid-phase synthesis. The phase composition of the obtained samples was controlled by X-ray phase analysis. The obtained diffraction patterns were processed and the crystallographic parameters were calculated by full-profile analysis. The conducted study of phase equilibria in the YO-SnO system at a temperature of 1400°C made it possible to determine for the first time the homogeneity region of yttrium stannate YSnO, which is shifted towards yttrium oxide and is 33.3-36 mol. % YO. The existence of a solid solution based on cubic yttrium oxide, extending to 3 mol. % SnO, was established. A comparative analysis of the effect of the radius of the substituting tetravalent cation on the width of the homogeneity region of the solid solution based on yttrium oxide was carried out. The absence of solubility of yttrium oxide in tin dioxide was noted.