Recent Advances in Antibiotic Degradation via Sulfate Radical Mediated AOPs: Bond Cleavage Mechanism, Fragmentation Pathways, and Interfacial Chemistry

Abstract Sulfate radical-based advanced oxidation processes (SR-AOPs) have emerged as promising and efficient technologies for the removal of antibiotics (ATBs) from aquatic environments due to their ability to generate highly reactive oxygen species and achieve effective contaminant degradation. The increasing persistence of ATBs in water bodies and their associated ecological and human health risks have stimulated extensive research on SR-AOP-based treatment strategies, including sulfate radical-driven oxidation, photocatalysis, electrochemical oxidation, sono-chemical processes, ozonation, and integrated hybrid systems. However, a comprehensive understanding of the molecular-level degradation mechanisms of ATBs, particularly the identification of reactive sites, bond cleavage pathways, and the roles of radical and non-radical reactive oxygen species (SO 4 •– / • OH/ O 2 •− / 1 O 2 ) remains insufficiently explored. This review provides a critical assessment of the sources, environmental occurrence, exposure pathways, and potential impacts of ATBs, along with existing regulatory frameworks for controlling antibiotic pollution. Furthermore, recent advances in SR-AOP strategies for ATB degradation are systematically discussed, with emphasis on reaction mechanisms, transformation products, structure reactivity relationships, and molecular fragmentation pathways. The review also highlights key challenges associated with catalyst development, oxidant utilization, energy consumption, and economic feasibility for large-scale applications. Finally, future research directions are proposed to promote sustainable catalyst design and accelerate the transition of SR-AOP technologies from laboratory investigations toward practical wastewater treatment applications. This review offers new mechanistic insights into ATB degradation and provides guidance for developing efficient and sustainable SR-AOP-based remediation strategies.