Microwave-assisted synthesis and characterization of Ti_(1-x)V_xO_2 (x = 0.0-0.10) nanopowders

摘要

Ti_(1-x)V_xO_2 (x = 0.0-0.10) nanopowders were successfully synthesized by a microwave-assisted sol-gel technique and their crystal structure and electronic structure were investigated. The products were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), Raman and UV-Vis spectroscopy. The results revealed that TiO_2 powders maintained the anatase phase for calcination temperature below 600 °C, but gradually changed to the rutile phase above 800 °C. The formation of the rutile phase was completed at 1000 °C. ForTi_(1-x)V_xO_2 (x = 0.05) powders, the phase transformation appeared at 600 °C. The absorption edge ofTi_(1-x)V_xO_2 (x>0) powders broadened to the visible region with increasing V concentration and a strong visible light absorption was obtained with 10% V doping. V doping and subsequent coexistence of both anatase and rutile phases in our Ti_(1-x)V_xO_2 nanoparticles are considered to be responsible for the enhanced absorption of visible light up to 800 nm.