Synthesis and properties of B–Ni–TiO₂/g-C₃N₄ photocatalyst for degradation of chloramphenicol (CAP) under visible light irradiation

Firstly, B, Ni co-doped TiO₂ (B–Ni–TiO₂) was prepared by sol–gel method, g-C₃N₄ was prepared by calcination method. Secondly, B–Ni–TiO₂/g-C₃N₄ composite photocatalysts were prepared by heating reflux method. The physical and chemical properties of the composite photocatalysts were characterized by XRD, XPS, UV–Vis, FT-TR, SEM, PL and TEM, HRTEM. The effect of different photocatalysts on the degradation of chloramphenicol was investigated. After the combination of g-C₃N₄ and B–Ni–TiO₂, the separation efficiency of photo-generated electrons and holes can be accelerated and the photocatalytic activity can be improved. When the ratio of g-C₃N₄ and B–Ni–TiO₂ was 1:4, the degradation rate of chloramphenicol by the composite photocatalyst was up to 95%. After five photocatalytic degradation experiments, the photocatalytic activity of the composite photocatalyst was not significantly reduced, the result showed that the composite photocatalyst had better stability and regeneration performance. The ·O₂⁻ was responsible for the photodegradation activity were determined and a possible mechanism was proposed.