Thermolytic Formation of Noble Metals and Their Oxides from Chloride Precursors: A Thermal Analysis Study

Abstract

The thermolysis of two compound series, namely, and was studied by differential scanning calorimetry, differential thermal analysis, and thermogravimetry. Product identification and confirmation of thermolysis pathways were accomplished by x‐ray powder diffraction analyses, moisture evolution analyses, and IR spectroscopy. The thermolysis was carried out both in reactive (air) as well as in inert (argon) atmospheres. In the case of , oxide was obtained as the major thermolysis product in air. In argon, metal was the major thermolysis product—the degree of oxide formation being a sensitive function of the partial pressure (or argon flow rate). The thermal stability of the oxide as well as the parent chloride precursor showed significant differences in the series. New data are presented for and . In both cases, intermediate formation of the trichloride was accompanied by oxide and metal formation depending on the gaseous ambient. Unlike the case of the Ir compound, no evidence for was found for the thermolysis of . Similarities and differences in data trends are discussed with the aid of thermochemical calculations. The results of this study may have implications in the synthesis of noble metals and their oxides for catalytic and electronic device applications.