Environmental-friendly synthesis of heterojunction photocatalysts g-C3N4/BiPO4 with enhanced photocatalytic performance

Heterojunction photocatalysts g-C3N4/BiPO4 with varying loadings of g-C3N4 were synthesized by ball milling process in different time, the synthetic method of which was a simple, rapid, economical, and easy-controlled way. The evaluation for the performance of as-prepared g-C3N4/BiPO4 was conducted by the degradation of tetracycline (TC) in stimulated sunlight condition. The superior performance was achieved from g-C3N4/BiPO4 heterostructure photocatalyst with 5 wt% g-C3N4 and ball milling time of 18 h, which could decompose 97% TC after 120 min illumination. The enhanced photocatalytic activity could be ascribed to the synergistic effects, including changes in morphology and structure after ball milling, increased specific surface area, outstanding visible-light absorption, and efficient separation of electron-hole pairs. The possible degradation mechanism was clarified by semiconductor energy band theory. This work may present a novel strategy for preparing heterojunction photocatalysts with high photoactivity and provide the analysis method of mechanism by combining theoretical calculations and experimental observations.

Automated summary

Heterojunction photocatalysts g-C3N4/BiPO4 with varying loadings of g-C3N4 were synthesized by ball milling process in different time, showing superior performance in degrading tetracycline under simulated sunlight condition. The enhanced photocatalytic activity was attributed to changes in morphology and structure after ball milling, increased specific surface area, outstanding visible-light absorption, and efficient separation of electron-hole pairs.