Construction of Z-type heterojunction BiVO4/Sm/α-Fe2O3 photoanode for selective degradation: Efficient removal of bisphenol A based on multifunctional Sm-doped modification

Metal Sm was doped in the BiVO4 to form B-Sm, and then B-Sm is combined with α-Fe2O3 to form B-Sm/α-Fe2O3 Z-type heterojunction to determine the mechanism of Sm in the photoanode heterojunction and oxidation system for lanthanide metal application in water treatment. In the photoanode mechanism, Sm utilizes near-infrared light at 980 nm to increase the light absorption intensity at 400–500 nm. It also decreases the transmission resistance from 25.91 Ω to 20.47 Ω, increases the number of oxygen vacancies in the system, and improves the carrier life and conductivity of the photoanode. In the oxidation system, the metal Sm acts as a photosensitizer to convert the O2 adsorbed on oxygen vacancies to 1O2, which increases the degradation rate of bisphenol A by 36%. Finally, the B-Sm-F photoanode was able to achieve 100% degradation within 60 min. Furthermore, the DFT results showed that the active species were selectively aggressive towards different sites of the bisphenol analogues. This provides a pathway for the selective degradation of bisphenol analogues.