Influence of calcination temperature on the structure, morphology and composition of micro α-Sb2O4 crystals

Micro α-Sb2O4 crystals have been successfully prepared using wet chemical precipitation method. The influence of calcination temperature on the structure, morphology and composition of samples was investigated by means of thermogravimetry-differential thermal analysis (TG-DTA), X ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive spectrometer (EDS). Results indicated that the precipitated precursor is pure Sb2O3 with an orthorhombic structure. Most of the Sb2O3 transformed into α-Sb2O4 below 400 °C, but the complete disappearance of all traces of Sb2O3 occurred after 800 °C. The product obtained at 600 °C possessed a layered surface morphology and relatively higher diffraction intensity ratio of (113)/(020). The O/Sb atomic ratios of microcrystals showed a monotonous decrease from 1.88 to 1.4 with an increase of calcination temperature, which indicated the increased oxygen-deficient tendency. Finally, the schematic formation process of micro α-Sb2O4 crystals has been proposed.