High-Activity and Excellent-Reusability Γ-Fe2o3/Sio2 Coating on Tc4 Titanium Alloy by Plasma Electrolytic Oxidation for Enhanced Photo-Fenton Degradation

Abstract

The immobilized coatings as a kind of promising Fenton-like catalysts with excellent performance and reusability for the efficient degradation of antibiotics and phenol under solar light irradiation is investigated. Herein, the porous γ-Fe2O3/SiO2 immobilized ceramic coating on TC4 titanium alloy as photo-Fenton catalyst was prepared via plasma electrolytic oxidation (PEO) technology. The as-obtained immobilized coating manifested a remarkable catalytic activity that the removal efficiencies of phenol and various antibiotics could reach more than 92% within 90 min, and presented excellent reusability after six runs in phenol removal. The high activity and excellent reusability of γ-Fe2O3 were attributed to the synergistic effect of multiple pathways to jointly produce abundant •OH, and the combination of γ-Fe2O3 and SiO2 in the coating could effectively reduce iron leaching during the heterogeneous photo-Fenton process, respectively. This work provides a novel strategy for the synthesis of high-performance photo-Fenton catalysts to dispose of wastewater in the future.

Keywords: Plasma electrolytic oxidation (PEO), γ-Fe2O3/SiO2 immobilized coating, Heterogeneous photo-Fenton, Antibiotics, Phenol