Cu0/Cu2+ Species Decorated Natao3 for Photocatalytic Degradation of Organic Pollutants

Abstract

The greatest challenge that limits the photocatalytic activity of sodium tantalate (NaTaO3) is the inferior visible light harvesting ability and the fast recombination of photoinduced charge carriers. In this study, Cu0/Cu2+ species modified NaTaO3 (Cu-NTO) was synthesized and characterized by a series of techniques. As expected, Cu-NTO possessed excellent photocatalytic performance for tetracycline hydrochloride (TCH) degradation. A rate constant of 72.24×10-3 min-1 was achieved over Cu-NTO under visible light irradiation within 40 min, which was 328-fold higher than that of NTO (0.22×10-3 min-1), The improved TCH degradation performance of Cu-NTO is ascribed to the raised visible light absorption ability and charge separation rate. The effects of catalyst dosages, humic acid dosages and inorganic anions in photoreaction were also investigated. Quenching experiments suggested that ·OH and 1O2 radicals are responsible for the TCH degradation. In addition, Cu-NTO displayed an excellent durability for the photocatalytic degradation of TCH. This study provides a new way to construct metal cocatalyst modified NTO catalyst for effective photocatalytic purification of wastewater.

Keywords: Sodium tantalate, Cu0/Cu2+ species, Photocatalytic, Tetracycline