Hydrothermal synthesis of Cd3TeO6 oxide powders

Abstract

Hydrothermal preparation of a transparent wide-gap conductor Cd3TeO6 from CdO, TeO2, H2O2, and alkali hydroxide was explored. The reaction without alkali hydroxide yielded only a small amount of Cd3TeO6, and NaOH gave a better yield than LiOH and KOH. The reactions without H2O2 did not form Cd3TeO6 at all. This observation indicated that H2O2 oxidized tellurium (IV) to the oxidation state VI in this system. The reactions at 240°C, the highest temperature available in this study, gave a better yield of Cd3TeO6 than the reactions at lower temperatures. After these optimizations, Cd3TeO6 was obtained as the dominant product.