WO3 anchored Fe single-atom composite for efficient photo−Fenton degradation of organic pollutants

Abstract

The overuse of antibiotics has led to severe environmental pollution, making it increasingly necessary to degrade them efficiently. A highly efficient Fe/WO3 single-atom catalyst has been developed to explore the synergistic effect in the photo-Fenton system for tetracycline degradation to address this issue. The WO3 carrier, pretreated in a H2/Ar atmosphere, possesses abundant oxygen vacancies, which narrow the band gap to enhance the visible-light harvesting ability and trap photogenerated electrons to form •O2− radicals. The Fe single atoms on the surface of WO3 significantly improve the separation of photogenerated electron-hole pairs due to the interfacial charge transfer effect. The photogenerated electrons can accelerate the Fe (III)/Fe (II) redox cycle. In the presence of H2O2, the Fe/WO3 single-atom catalyst exhibited outstanding photo-Fenton performance in tetracycline degradation. It showed good stability, as confirmed by tests in a continuous-flow reactor system. Finally, the purification capability was examined by plant growth experiments. The study could pave the way for the rational design of high-efficiency Fe single-atom catalysts for enhanced Fenton ability toward water purification.