Preparation of Ag-AgVO3/g-C3N4 composite photo-catalyst and degradation characteristics of antibiotics

The degradation of tetracycline by silver vanadate (AgVO3), graphite-like carbon nitride (g-C3N4) and their composites was studied by visible light photocatalysis. Their structures and morphologies were studied by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Their degradation intermediates were analyzed by GC–MS. Nanorod silver vanadate was synthesized by hydrothermal method. The results show that the gap between nanorods is reduced by adding spinning carbon nitride, and the photocatalytic performance of the composite is stronger than that of single material. The reaction rate constants of Ag-AgVO3/g-C3N4 composites were 0.0298 min−1, 2.4 and 2.0 times that of g-C3N4 (K=0.0125 min-1) and AgVO3 (K=0.0152 min-1), respectively. At 120 minutes, the degradation rate of the composites reached 83.6%. The degradation of tetracycline was confirmed by GC–MS, and a possible degradation process was proposed.