Rapid degradation of levofloxacin by p-n heterojunction AgFeO2/Ag3VO4 photocatalyst: Mechanism study and degradation pathway

Background: The accumulation of antibiotics in water systems has received considerable global attention due to its detrimental effects. There is an urgent need to develop rapid and efficient methods for the degradation of antibiotics.Methods: In this work, a highly efficient AgFeO2/Ag3VO4 photocatalyst was successfully fabricated by a hydrothermal method and analyzed using different techniques. Under visible light irradiation, photocatalytic behavior of AgFeO2/Ag3VO4 heterojunctions in the degradation of levofloxacin is investigated. Significant findings: The results showed that p-n heterojunction was formed between AgFeO2 and Ag3VO4, which improved the separation and transfer of photogenerated charge carrier under the action of the internal electric field. The apparent reaction rate of AgFeO2/Ag3VO4 heterostructure toward degradation of levofloxacin reached to 0.2770 min-1, which was about 2.15 times and 36.73 times larger than those of Ag3VO4 and AgFeO2, respectively, and much larger than other counterparts. Furthermore, possible photocatalytic degradation pathway of levofloxacin was comprehensively determined by LC-MS analysis. This work would provide in-depth understanding on the efficient photocatalytic removal of antibiotics for sustainable environmental remediation.