Synthesis and Characterization of Vanadium Doped TiO2 for the Visible Light-Driven Photocatalytic Activity

V-doped TiO2 nanoparticles (NPs) was synthesized by a sol-gel hydrolysis method using titanium butoxide (Ti(OBu)(4)) and vanadyl acetylacetonate (VO(acac)(2)) as a precursor and dopant, respectively. The effects of different V : Ti ratios on the crystal structure, band gap energy and photocatalytic activity have been investigated. The photocatalytic activity of V-doped TiO2 NPs was evaluated using UV-vis absorption spectroscopy through degradation of a methyleneblue (MB) solution under visible light irradiation. Characterization by Raman and X-ray diffraction pattern shows that V was doped effectively and oxygen vacancies and various defects or Ti3+ centers were formed. Energy dispersive X-ray (EDX) and X-ray photoelectron spectroscopy (XPS) results indicated the presence of V in the TiO2. The band gap energy of V-doped TiO2 NPs was determined to be 2.3 eV, with a distinct red-shift confirmed by diffuse reflectance spectroscopy (DRS). The photocatalytic activity of V-doped TiO2 NPs exhibited highly enhanced visible-light-induced photocatalytic performance compared with pure TiO2 NPs.