Enhanced Photocurrent and Photocatalytic Degradation of Methyl Orange by V-N Codoped TiO2Nanotube Arrays Cooperated with H2O2

To extend the photo response of TiO 2 further into the visible light region, TiO 2 nanotube arrays codoped with vanadium and nitrogen were synthesized by anodization process, followed by impregnation and calcination process. X-ray photoelectron spectroscopy (XPS) revealed the existence of interstitial N and V (V 4+ and V 5+ ) in V, N codoped TiO 2 catalysts, which was beneficial to narrow the bandgap and separating charges. Higher photocurrent density displayed by the V, N codoped TiO 2 nanotube arrays showed that more photo-induced electrons were generated, therefore effectively improved the catalytic activity. V, N codoped samples were used for the photodegradation of methyl orange (MO) in aqueous solution in presence of H 2 O 2 . H 2 O 2 is used to serve as an electron scavenger and a precursor for •OH radicals, thus significantly accelerating the photodegradation of MO under visible light irradiation. A synergistic effect between V, N codoped TiO 2 catalyst and H 2 O 2 contributed to the high degradation activity toward MO.