Microwave-assisted synthesis and characterization of Ti _{1 - X}V_xO₂ (x = 0.0-0.10) nanopowders

Ti_{1 - x}V_xO₂ (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 TiO₂ 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. For Ti _{1 - x}V_xO₂ (x = 0.05) powders, the phase transformation appeared at 600 °C. The absorption edge of Ti _{1 - x}V_xO₂ (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.