Enhanced photocatalytic removal of amoxicillin with Ag/TiO2/mesoporous g-C3N4 under visible light: property and mechanistic studies

In present study, an efficient ternary Ag/TiO 2 /mesoporous g-C 3 N 4 (M-g-C 3 N 4 ) photocatalyst was successfully synthesized through depositing Ag nanoparticles (NPs) on the surface of TiO 2 /M-g-C 3 N 4 heterojunction. Ag/TiO 2 /M-g-C 3 N 4 nanocomposite displayed the highest degradation efficiency for amoxicillin (AMX) compared to TiO 2 /M-g-C 3 N 4 heterojunction, M-g-C 3 N 4 , and bulk-g-C 3 N 4 (B-g-C 3 N 4 ). The removal efficiency of AMX in real situation, surface water (SW), hospital wastewater (HW), and waste water treatment plant (WWTP) also were studied to illustrate the effectiveness of Ag/TiO 2 /M-g-C 3 N 4 photocatalysts. The vulnerable atoms in AMX structure were revealed through DFT calculation. Additionally, the dominating active groups produced in time of the photocatalytic procedure were determined on account of free radical trapping experiments and ESR spectra. The mechanism of photocatalytic degradation was proposed and verified. The transfer of the electrons and the inhibition of the recombination of photogenerated electron-holes were enhanced effectively under the synergistic effect of the Ag NPs and TiO 2 . As a consequence, the catalytic activity of the composite was improved under visible light.