Preparation and Characterization of Solid Solutions of TiO₂ and Trirutile Type MSb₂O₆ (M=Cu, Zn, Mg, Co and Ni)

Abstract

The solid solution of trirutile-type MSb₂O₆ (M=Cu, Zn, Mg, Co and Ni) and TiO₂ with the molar rates x=0.125, 0.25, 0.5 and 0.75 in (MSb₂O₆)_x(TiO₂)_1-x was prepared by a solid state reaction. The results showed that the solid solutions were formed except for (MSb₂O₆)_0.75(TiO₂)_0.25 (M=Mg and Co) and x=0.50 and 0.75 in (NiSb₂O₆)_x(TiO₂)_1-x, and were crystallized in trirutile type structure. Diffuse reflectance spectroscopy measurement for their powders indicated that the energy bandgaps were approximately 2.1 eV for (CoSb₂O₆)_x(TiO₂)_1-x (x=0.125, 0.25 and 0.5), and were approximately 2.6 and 2.4 eV for (NiSb₂O₆)_x(TiO₂)_1-x (x=0.125 and 0.25) and (CuSb₂O₆)_x(TiO₂)_1-x (x=0.125, 0.25, 0.5 and 0.75), respectively. The photocatalytic activity for visible light was observed in (CoSb₂O₆)_x(TiO₂)_1-x and (CuSb₂O₆)_x(TiO₂)_1-x.