Enhanced Photocurrent and Photocatalytic Degradation of Methyl Orange by V-N Codoped TiO2 Nanotube Arrays Cooperated with H2O2

Abstract

To extend the photo response of TiO2 further into the visible light region, TiO2 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 (V4+ and V5+) in V, N codoped TiO2 catalysts, which was beneficial to narrow the bandgap and separating charges. Higher photocurrent density displayed by the V, N codoped TiO2 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 H2O2. H2O2 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 TiO2 catalyst and H2O2 contributed to the high degradation activity toward MO.