The highly improved visible light photocatalytic activity of BiOI through fabricating a novel p–n heterojunction BiOI/WO3 nanocomposite

Abstract

A novel BiOI/WO₃ heterostructure was successfully synthesized using a facile ultrasonic process and used for the photocatalytic degradation of organic pollutants. The different BiOI loadings were investigated at the same time in this study. The heterostructure of BW-1.0 exhibited improved photocatalytic activity in comparison with pristine BiOI and WO₃ with a 10.3- and 12.6-fold increase for Rhodamine B (RhB) degradation under visible light, respectively. The BiOI/WO₃ heterostructured catalysts all exhibit the highest photocatalytic activity for degradation tetracycline (TC) under visible light. The excellent photocatalytic performance can be ascribed to the BiOI in close contact with WO₃, which forms a heterojunction structure. This heterostructure composite photocatalyst results in an efficient charge separation at the interface, which is confirmed by photoelectron and photoluminescence spectroscopy. Moreover, trapping experiments indicated that h⁺ and ˙O²⁻ were the main active species, with DMPO–˙O₂⁻ and DMPO–˙OH both being investigated. Moreover, the prepared sample shows good stability and recyclability, which are beneficial for its practical applications.