Improved visible light activation of peroxymonosulfate by novel Bi modified TiO2 /O-loaded g-C3N4 Z-scheme heterojunction for efficient degradation of trichloroethylene

Through a facile sol-gel method, a novel Z-scheme heterojunction BTMO was synthesized by combining Bi-modified TiO₂ with oxygen-modified graphitic carbon nitride. Bi serves as an electron mediator in the catalyst, facilitating the transfer of excited electrons to MCN-O. Infrared characterization reveals that the doping of O increases the adsorption of peroxymonosulfate by the catalyst, promoting the reaction between electrons on the conduction band of MCN-O and PMS. The as-prepared BTMO Z-scheme heterojunction significantly improved the degradation rate of trichloroethylene was in BTMO/PMS system. TCE degradation efficiency in BTMO/PMS photocatalytic system could reach 99.8 % within 1 hour. According to the results of electron paramagnetic resonance and quenching experiments, sulfate radical and holes are the main reactive species in BTMO/PMS system. This novel photocatalyst also exhibited excellent durability. This work provides a new method for solving environmental problems through visible light photocatalysis.