Efficient photocatalytic degradation of antibiotics using Z-scheme MIL-88(Fe)/Ti3C2/MoO3: mechanistic insights and toxicity assessment

Abstract

Antibiotic residues cause water contamination and disrupt aquatic ecosystems. Herein, we reported the fabrication of a novel Z-scheme heterojunction, MIL-88A(Fe)/Ti₃C₂/MoO₃ (MTO), for safe and efficient removal of antibiotics. Ti₃C₂ was introduced into the MIL-88A(Fe)/MoO₃ (MO) heterojunction as an electronic mediator to accelerate charge separation. Consequently, the ternary MTO achieved a tetracycline (TC) degradation rate 2.5 times higher than that of MO. Notably, the MTO heterojunction maintained high TC degradation efficiency over 36 consecutive hours without significant decline. Photogenerated holes, hydroxyl radicals, and superoxide radicals synergistically led to efficient and deep mineralization of TC. Furthermore, toxicity assessments were performed using Toxicity Estimation Software Tool (T.E.S.T.), bacteria (S. aureus and E. coli) cultivation, wheat germination and cultivation. The results all confirmed the safe degradation of TC. Therefore, this study provides a promising strategy for photocatalytic removal of antibiotics and promotes sustainable water purification technologies.