Effect of Cu doping on the photocatalytic activity of InVO for hazardous dye photodegradation under LED light and its mechanism.

Cu doped InVO (xCu-InVO (x = 0.06-0.15 wt %) was synthesized by a facile one-pot hydrothermal method for the removal of methylene blue (MB) under LED light irradiation. The X-ray photoelectron spectroscopy (XPS) analysis indicated the coexistence of V and V species due to the O-deficient nature of the xCu-InVO. The synthesized photocatalysts displayed a morphology of spherical and square shaped particles (20-40 nm) and micro-sized rectangle rods with a length range of 100-200 μm. The xCu-InVO exhibited superior adsorption and photodegradation efficiency compared to pristine InVO and TiO due to the presence of O vacancies, V/V species, and Cu dopant. The optimum reaction conditions were found to be 5 mg L (MB concentration), pH 6, and 100 mg of photocatalyst mass with a removal efficiency and mineralization degree of 100% and 96.67%, respectively. The main active species responsible for the degradation of MB were OH radicals and h. Reusability studies indicated that the 0.13Cu-InVO was deactivated after a single cycle of photocatalytic reaction due to significant leaching of V and Cu species.