Visible-light-driven tetracycline hydrochloride degradation via ZnTi-LDHs/Ce2S3 Z-scheme heterojunctions: Performance and mechanistic analysis

Abstract

The refractory and hard-to-dispose tetracycline hydrochloride (TC) poses an enormous threat to human health and the water environment. Herein, a novel Z-scheme ZnTi-LDHs/Ce2S3 heterojunction photocatalyst was successfully developed for TC degradation under visible light conditions. This sophisticated material demonstrated a remarkable degradation rate of 0.0124 min−1, marking a noteworthy advancement compared to ZnTi-LDHs, Ce2S3, and the commonly reported LDHs/LDHs-based composites, with an approximate one-order-of-magnitude improvement. The inherent synergy between Ce2S3 and LDHs manifested as a Z-scheme charge transfer channel, augmenting visible-light absorption, and fostering carrier separation. Both O2·- and h+ played critical roles in the TC degradation process, mediating reductive and oxidative pathways, respectively. ZnTi-LDHs/Ce2S3 demonstrated robust reusability and broad applicability for degrading diverse dyes and antibiotics. This work demonstrated a promising protocol for crafting efficient Z-scheme heterojunction photocatalysts based on LDHs and expanded our understanding and potential applications of photocatalytic degradation mechanisms for antibiotics.