Solar-driven photocatalytic removal of organic pollutants over direct Z-scheme coral-branch shape Bi2O3/SnO2 composites

Abstract

Here, we report a feasible strategy to construct a Z-scheme Bi2O3/SnO2 composite via a facile hydrothermal method. Photocatalytic activity of the as-prepared photocatalysts was evaluated through photocatalytic degradation of bisphenol A (BPA) under simulated sunlight irradiation. A photocatalytic efficiency of 93.42% was achieved by 1Bi2O3/SnO2 during 60 min of irradiation, which was 14.97- and 2.54-fold greater than the photocatalytic efficiency of pure SnO2 and Bi2O3, respectively. In addition, the composite was effective in the photocatalytic decomposition of several antibiotics. Degradation conditions, such as the catalyst dosage, the initial concentration, and pH of BPA aqueous solution, were also investigated. The enhanced photocatalytic degradation efficiency of Bi2O3/SnO2 composites was attributable to the increased absorption of light, as well as the effective separation of photo-induced carriers that resulted from the formation of a Z-scheme heterojunction. The main active species in photocatalytic degradation of BPA by Bi2O3/SnO2 composite were h+ and 1O2. This highly efficient and broad-spectrum photocatalyst renders it a promising candidate for water pollution control.