Synthesis of Monodispersed SnO2 Microspheres via Solvothermal Method

Monodispersed SnO2 microspheres with diameter about 1 μm were successfully synthesized by solvothermal method at 180 OC for 12 h, using PEG as template, SnCl4
• 5H2O and urea as raw materials. Effects of concentration and molecular weight of PEG, hydrothermal temperature on the morphology of SnO2 microspheres were studied. The as-prepared samples were characterized by XRD and SEM and the formation mechanism of microspheres was discussed. Furthermore, the room temperature photoluminescence spectroscopy (PL) was investigated. The results indicate that the SnO2 microspheres are self-assembled by nanocrystals. PEG has a great influence on the morphology and diameter of microspheres while hydrothermal temperature and time influence the dispersity and uniformity. In the PL spectra, a broad band (320-450 nm) is exhibited and the stronger peak at about 406 nm reveals the existence of defects in the samples.