Advanced photocatalytic Fenton-like process over biomimetic hemin-Bi2WO6 with enhanced pH

Abstract

Abstract Highly-efficient technologies are urgently needed to remove environmental organic pollutants. Photocatalytic degradation and Fenton (-like) process are often used to remove organic pollutants. But simplex photocatalysis is a rather slow process, while Fenton-like process is often limited by low pH levels. Introducing photocatalysis into Fenton-like process to form photocatalytic Fenton-like system is a promising method to overcome these drawbacks. This work investigated a simulated-solar light (SSL) driven photocatalytic Fenton-like process with using a novel biomimetic photocatalyst hemin-Bi2WO6 induced by H2O2 (SSL/H-Bi2WO6/H2O2 process) to degrade organic pollutants. H-Bi2WO6 possesses lower fluorescence intensity and faster electron transport than pristine Bi2WO6. Additionally, combined experimental and theoretical investigations indicated that SSL/H-Bi2WO6/H2O2 process revealed a high catalytic activity with enhanced pH tolerance. Furthermore, trapping experiments and electron spin resonance tests were used to explore the reaction mechanism of photodegradation. Presumably, the degradation of organic pollutants over SSL/H-Bi2WO6/H2O2 process was ascribed to ·OH, h+, and ·O2− radical species, and Fe(IV) O active species generated from the interaction of H2O2 with the variable valence state of iron on H-Bi2WO6. Overall, this work puts forward a new possibility for aqueous organic pollutants removal via SSL/H-Bi2WO6/H2O2 process, which may promote the application of photocatalytic Fenton-like process and biomimetic catalysis.