A hydrothermal assisted method to prepare Samarium Tungstate sheets at lowered reaction temperature

摘要

In the present work, a hydrothermal-assisted synthesis of sheet-like Samarium Tungstate powders is developed. The structures and morphology of these powders were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Results show that a new phase of SmWO_4(OH) was obtained during the hydrothermal reaction. This phase was further used as precursor to obtain Sm_2WO_6 crystallites with much lowered heating temperature during the calcination. Furthermore, both of the SmWO_4(OH) and Sm_2WO_6 products were found to exhibit sheet-like microstructures without obvious morphological differences, suggesting that controlling the precursor microstructure is an effective approach to maintain the calcined Sm_2WO_6 morphology. Finally, the schematic comparison between hydrothermal assisted method and conventional solid state reaction method was presented.