Construction of Ag decorated on InVO4/g-C3N4 for novel photocatalytic degradation of residual antibiotics

Abstract

In this study, InVO4 was effectively hybridized with g-C3N4 to create InVO4/g-C3N4 Z-scheme heterojunction. Ag metals were also successfully decorated on the InVO4/g-C3N4 to further improve its photocatalytic performance for tetracycline degradation. Scavenger experiments were conducted to investigate photocatalytic degradation mechanism of the synthesized materials. The characterization and experimental results showed that InVO4 and g-C3N4 would absorb incident visible light to induce electrons to their conduction band (CB) leaving holes at their valence band (VB). Then, photo-induced electrons in the InVO4 CB would move to the g-C3N4 VB to recombine with its holes leading to preservation of photo-induced electrons at the g-C3N4 CB, which has high reduction potential, and holes in the InVO4 VB, which has high oxidation potential, for effective degradation of tetracycline. When Ag metals were decorated on InVO4/g-C3N4, plasmon resonance of Ag would effectively increase light absorption and induce electron-hole separation of the InVO4 as well as the g-C3N4. The decorated Ag also acted as charge mediator to enhance electron transfer from the InVO4 CB and the g-C3N4 VB to improve electron-hole separation or photocatalytic efficiency of the InVO4/g-C3N4. Therefore, the Ag decorated on InVO4/g-C3N4 (AIC) presented novel photocatalytic performance for degradation of tetracycline. Finally, the regenerating experiment results indicated that the AIC could be effectively regenerated after being used.