CuO‐Based Heterojunction Photocatalysts and Coupled Oxidation Systems for Antibiotic Degradation: From Interfacial Design Toward Practical Water Treatment

Abstract

The pervasive contamination of aquatic environments by antibiotics poses a critical public health and ecological threat. Photocatalytic advanced oxidation with copper oxide (CuO) is promising for antibiotic mineralization, yet its efficiency is limited by rapid charge recombination and photocorrosion. Constructing CuO‐based heterojunctions has emerged as a key strategy to overcome these barriers. This review provides a critical and focused overview of recent progress in CuO‐based heterojunctions for antibiotic degradation, covering pure photocatalysis, photo‐assisted advanced oxidation, dark catalytic activation, and photo‐enzyme synergistic systems. We outline primary synthesis methods (hydrothermal, in situ growth, calcination, green synthesis) and elucidate the charge transfer mechanisms of type‐II, Z‐scheme, and S‐scheme heterojunctions. This paper discusses how interfacial engineering, including oxygen vacancies (OVs), doping, morphology control, and plasmonic effects, enhances activity. Degradation performance toward tetracyclines, sulfonamides, and fluoroquinolones is comprehensively reviewed, along with structure–activity correlations. Finally, we address remaining challenges in scalable synthesis, operational stability, and real‐water applicability, and outline future directions involving novel heterojunction design, machine learning‐assisted optimization, in situ mechanistic characterization, and reactor development, aiming to bridge the gap from fundamental research to practical water treatment.