A novel Z-type ZnIn2S4 nanosheet-coated TiO2 nanorods heterostructures for efficient photocatalytic degradation of tetracycline

The construction of heterojunction structures of semiconductor photocatalysts to achieve efficient separation of photogenerated electron-hole pairs is important for enhancing tetracycline (TC) degradation efficiency. In this work, TiO2/ZnIn2S4 (TNZIS) Z-type heterostructures were prepared by in situ growth of ultrathin ZnIn2S4 on TiO2 nanorods. The degradation efficiency (90.0%) of TNZIS heterojunction for TC was significantly higher than that of pure TiO2 and ZnIn2S4. This is mainly because the construction of Z-type heterojunction photocatalyst not only increases the specific surface area, exposes abundant active sites, and improves the utilization of light, but also provides a wide and short transport path for carriers, and inhibits fast recombination of photogenerated electron holes. At the same time, the charge transfer of Z-type heterojunctions was investigated in depth after a series of tests. Finally, the mechanism of photocatalytic degradation of TC by TNZIS heterojunctions was proposed. This work is expected to provide new ideas for the design and preparation of novel Z-type heterojunction photocatalysts.