Construction of Z-scheme SbVO4/g-C3N4 heterojunction with efficient photocatalytic degradation performance

Abstract

As visible light responsive materials, g-C₃N₄ has become an outstanding research object for photocatalysis due to its facile synthesis, excellent chemical and thermal stability. In this paper, a Z-scheme SbVO₄/g-C₃N₄ heterojunction was successfully constructed by thermal polymerization method. The synthesized SbVO₄/g-C₃N₄ nanocomposite showed efficient photocatalytic activity on tetracycline (TC) degradation. The photocatalytic degradation of TC follows a first-order kinetic model, in which ·O₂⁻ and ·OH free radicals play a major role. The formation of Z-scheme heterojunction between SbVO₄ and g-C₃N₄ can effectively promote the separation of photogenerated electron-hole pairs and the generation of ·O₂⁻ and ·OH. The photocatalytic removal rate of TC reached 82.3 % within 150 min under visible light. The as-synthesized SbVO₄/g-C₃N₄ heterojunction can still maintain good stability. Furthermore, a photocatalytic degradation mechanism for the SbVO₄/g-C₃N₄ heterojunction is proposed.