A novel heterostructure ZnO/PbBiO2Cl as a type-II photocatalyst for persulfate activation in tetracycline degradation under visible light

Abstract

In the present study, the novel ZnO/PbBiO2Cl heterostructure nanocomposite was fabricated by the simple hydrothermal method. The synthesized nanocomposite was applied to remove tetracycline (TC) in the photocatalytic process under visible light. Different analyses (XRD, FTIR, EDX, DRS, BET, TEM, FESEM, and PL) were carried out to determine the characterization of materials. The results showed that compared to pure zinc oxide, the ZnO/PbBiO2Cl (40%) sample has excellent efficiency in TC degradation, which is about 97% in 150 min. Also, the effect of parameters such as initial TC concentration, solution pH, and catalyst dosage was evaluated. After that, ZnO/PbBiO2Cl photocatalyst was used for persulfate (PS) activation. The kinetic study showed that the reaction rate constant in the ZnO/PbBiO2Cl (40%) + PS system is approximately 23 and 4 times faster than ZnO and ZnO/PbBiO2Cl (40%) samples, respectively. Furthermore, the complete TC removal was achieved in 50 min. Finally, by identifying the active species and using the optical properties of photocatalysts, the degradation mechanism was predicted. Accordingly, it is expected that by using highly stable ZnO/PbBiO2Cl photocatalysts, TC pharmaceutical pollutants can be removed with high efficiency.