The basic steps in the reaction of Nd2(SO4)3 with CS2 were studied by thermogravimetric techniques to elucidate the reaction mechanism of the formation of Nd2S3. The Nd2(SO4)3 first decomposes to Nd2O2SO4 in the range 500-650°C, depending on the heating rate. Nd2O2SO4 is further deoxygenated to Nd2O2S, which forms a disulfide phase at lower temperatures (500-600°C) by reaction with CS2. Neodymium disulfide, which exhibits a wide range of non-stoichiometry (NdS1.876-NdS2), decomposes into Nd2S3 above 600°C. At lower heating rates (1 and 5°C min-1), orthorhombic Nd2S3 is formed in a single phase on heating to 1100°C. In contrast, non-stoichiometric cubic Nd2S3 - x is formed together with orthorhombic Nd2S3 when the heating rate is as high as 10°C min-1.
ASJC Scopus subject areas
- Condensed Matter Physics
- Physical and Theoretical Chemistry