Photocatalytic degradation of antibiotics using a Li-C3N4/ZnO/BiOI: Insights on the electron transport pathways

Background Environmental pollution demands the fabrication of suitable nano-photocatalyst that works under visible-light irradiation. The effective interfacial engineering is required for better separation of charges. Semiconductor heterostructure promotes the practical separation of electron-hole pairs and enhances the carrier separation efficiency, which has broad application prospects in photocatalytic degradation of Antibiotics. However, it remains a significant challenge to construct high-quality directly heterostructure effectively. Methods In this work, a hierarchical ternary heterojunction (Li-C 3 N 4 /ZnO/BiOI) was facilely synthesized by employing an in-situ hydrothermal strategy with different ratios using Li-C 3 N 4 as an anchor, in which the interaction at heterointerfaces was enhanced to improve the photocatalytic performance. Significant findings The photocatalytic degradation experiment was carried out with Tetracycline (TC), and the effect of the molar ratio of Li-C 3 N 4 /ZnO to BiOI on the photocatalytic degradation performance was quantitatively investigated. Benefiting from the unique electronic structure of heterostructure, the results show that a degradation rate of 92.62% was achieved for 10 mg/L TC solution within 20 min. Moreover, Li-C 3 N 4 /ZnO/BiOI-5 offered high photocatalytic activity due to the type II and Z transport, resulting in a small forbidden band gap. The charge transport pathway improves the separation of photogenerated electron-hole pairs in Li-C 3 N 4 /ZnO/BiOI. This study provides a promising avenue for rational design and application of ternary composites.