Construction of DyVO4/nitrogen deficient g-C3N4 composite for enhanced visible-light photocatalytic activity for tetracycline degradation

The defects engineering takes effects on regulating the electronic structure to enhance the optical absorption, and acting as the capture centers of charge carriers to hinder the recombination of electron hole pairs. In this work, DyVO4/nitrogen deficient g-C3N4 (DVO/CNx) composite photocatalysts were successfully synthesized by a simple precipitation-calcination method, which showed excellent visible-light photocatalytic activity for the degradation of tetracycline (TC). Among them, 10 % DVO/CNx (with the mass ratio of 10 % DVO in the composites) exhibited the optimum photocatalytic performance (within 1 h, 92 % degradation of TC), which was higher than pure phase materials (CN, CNx and DVO) and DVO/CN heterojunction photocatalyst. The dramatically enhanced photocatalytic activity of DVO/CNx composite can be ascribed to its defect structure and the construction of heterojunction, which can simultaneously improve the visible-light absorption and separation efficiency of photo-generated electron-hole pairs. More importantly, the DVO/CNx photocatalyst exhibits high stability and reusability.