Fabrication of highly active Z-scheme Ag/g-C3N4-Ag-Ag3PO4 (110) photocatalyst photocatalyst for visible light photocatalytic degradation of levofloxacin with simultaneous hydrogen production

The capacity of redox and the separation efficiency of electron-hole pairs are important indexes for evaluating the performance of photocatalyst. Herein, a novel Z-scheme Ag/g-C3N4-Ag-Ag3PO4 (1 1 0) photocatalyst is prepared by photo-assisted isoelectric point way. The prepared samples are characterized by XRD, SEM, TEM, EDS mappings, XPS, UV vis, PL, TPR and EIS. The Z-scheme Ag/g-C3N4-Ag-Ag3PO4 (1 1 0) photocatalytic system exposes the Ag3PO4 (1 1 0) crystal plane with strong oxidizing ability and provides a large producing hydrogen reduction surface of g-C3N4 at the same time. Therefore, the photocatalytic degradation of levofloxacin (LEV) with simultaneous hydrogen production can be effectively achieved under visible light irradiation. Besides, the influence factors such as visible light irradiation time, sacrificial agents, Z-scheme Ag/g-C3N4-Ag-Ag3PO4 (1 1 0) photocatalyst dosage, initial pH and used times are studied systemically. Based on trapping tests and ESR analyzes, the mainly active species are confirmed in the photocatalytic degradation of LEV. Finally, the photocatalytic reaction mechanism on degradation of organic pollutants with simultaneous production hydrogen caused by Z-scheme Ag/g-C3N4-Ag-Ag3PO4 (1 1 0) photocatalyst is proposed.