Visible-light responsive Ag-doped ZnO/InVO4 composite photocatalyst for efficient degradation of tetracycline and Inactivate E. coli

Ternary heterostructured xAg/ZnO/InVO4 (x=2 %,5 %,7 %) composites were synthesized by a simple hydrothermal method. The prepared photocatalyst underwent characterization using a series of techniques, including XRD, BET, SEM, TEM, FTIR, and Raman spectroscopy. The photoluminescence spectra and electrochemical studies indicated that the addition of Ag promotes the effective separation of photogenerated charge carriers. The 5 % Ag/ZnO/InVO4 photocatalysts under visible light irradiation improved tetracycline removal to 88.6 % within 120 min. The highest degradation performance was achieved under the photocatalyst addition of 30 mg and pH 7. Moreover, the 5 % Ag/ZnO/InVO4 exhibited bactericidal activity against E. coli up to 100 %, which was significantly higher than that of the sum of ZnO, InVO4, and ZnO/InVO4. The radical scavengers trapping experiments revealed that ·OH, h+, and e- were generated in the photocatalytic process, and h+ played a major role in tetracycline degradation with a contribution of 72.3 %. According to the results of photochemical characterization and capture experiments, a detailed photocatalytic mechanism was proposed that the heterostructured combination of Ag, ZnO, and InVO4 provided synergistic photocatalytic activity through an efficient electron transfer process. An innovative concept for the process of environmental remediation is presented for the natural solar energy treatment of organic pollutants in bodies of water.