Visible-Light-Driven LaFeO3/CdS Heterojunction Photocatalysts for Photo-Fenton Degradation of Levofloxacin

A series of composite photocatalysts LaFeO3/CdS-x (LFO/CS-x, x=10-50 wt%) were prepared by a simple sol-gel and solvothermal two-step method for photo-Fenton degradation of levofloxacin (LVF). The removal rate of LVF by LFO/CS-40 reached 97.3 % within 100 min, showing excellent photocatalytic activity compared with LaFeO3 and CdS. The prepared composites were characterized and analyzed by XRD, FT-IR, DRS, SEM, HRTEM, XPS, photoelectrochemical analysis and other techniques. Mechanistic investigations show that the heterojunction structure, can promote the separation and migration of photogenerated electron-hole pairs, and the photogenerated charges can induce the generation of various active species under the synergistic effect of H2O2, and then efficiently degrade pollutants. Additionally, the effects of different parameters on the photo-Fenton degradation were explored, and the good stability of composites is proved by cycling tests. The LFO/CS-40 composite photocatalyst designed in this work has potential application prospects in the green and efficient treatment of antibiotic wastewater.