Fabrication of a CuBi2O4/g-C3N4 p-n heterojunction with enhanced visible light photocatalytic efficiency toward tetracycline degradation

As the misuse and overuse of tetracycline (TC) contribute to water pollution, it is imperative to explore an efficient and cost-effective approach for the removal of TC in aqueous solution. Photocatalysis is a green and sustainable chemical technique because of its utilization of solar energy. From the view of practical application, it is significant to design a highly efficient, stable, eco-friendly and economical photocatalyst. In this work, CuBi2O4/g-C3N4 p-n heterojunctions with different CuBi2O4 content (10-90 wt%) were prepared via a facile calcining method. The CuBi2O4/g-C3N4 heterojunctions exhibit superior photocatalytic activity in the degradation of TC, compared with pristine CuBi2O4 and g-C3N4. The optimum photoactivity of 70 wt% CuBi2O4/g-C3N4 is up to 4 and 6 times higher than that of CuBi2O4 and g-C3N4, respectively. The enhanced photocatalytic activity can be attributed to p-n junction photocatalytic systems, which effectively promote charge carrier separation and transfer. It is anticipated that the design of CuBi2O4/g-C3N4 could offer the insight needed to construct inexpensive and highly efficient g-C3N4-based heterojunction photocatalysts, to relieve urgent environmental deterioration.