Preparation of Hydrated Potassium Molybdenum Bronzes and Their Thermal Decomposition

Three kinds of hydrated potassium bronze, K0.23(H2O)0.65MoO3.00(HyK–AD), K0.23(H2O)0.43MoO3.00(HyK–H2), and K0.23(H2O)0.27MoO3.00(HyK–H1), were obtained from hydrated sodium bronzes by cation exchange. Hydrated potassium bronzes dried under vacuum are of two types. The first, HyK–H2, belongs to the six-coordination type and the second, HyK–H1, belongs to the eight-coordination type. When hydrated bronzes were heated in nitrogen, they turned into a mixture of the blue potassium bronze, K0.3MoO3, and MoO3. In contrast, those heated in air decomposed to K2Mo4O13and MoO3.