The inefficiency of conventional biological treatment for removing sulfamethoxazole (SMX) is posing potential risks to ecological environments. In this study, an intimately coupled photocatalysis and biodegradation (ICPB) system consisting of Fe³⁺/g-C₃N₄ and biofilm was fabricated for the treatment of synthetic domestic wastewater containing SMX. The results showed that this ICPB system could simultaneously remove 96.27 ± 5.27% of SMX and 86.57 ± 3.06% of COD, which was superior to sole photocatalysis (SMX 100%, COD 4.2 ± 0.74%) and sole biodegradation (SMX 42.21 ± 0.86%, COD 95.1 ± 0.18%). Contributors to SMX removal in the ICPB system from big to small include LED photocatalysis, biodegradation, LED photolysis, and adsorption effect of the carrier, while COD removal was largely ascribed to biodegradation. Increasing initial SMX concentration inhibits SMX removal rate, while increasing photocatalyst dosage accelerates SMX removal rate, and both had no impact on COD removal. Our analysis of biofilm activity showed that microorganisms in this ICPB system maintained a high survival rate and metabolic activity, and the microbial community structure of the biofilm remained stable, with Nakamurella and Raoultella being the two dominant genera of the biofilm. This work provides a new strategy to effectively treat domestic wastewater polluted by antibiotics.

常规生物处理去除磺胺甲恶唑（SMX）效率低下，对生态环境构成潜在风险。^{在这项研究中，由 Fe 3+} /gC ₃ N ₄组成的紧密耦合的光催化和生物降解 (ICPB) 系统并制备了生物膜用于处理含有 SMX 的合成生活废水。结果表明，该ICPB系统可同时去除96.27±5.27%的SMX和86.57±3.06%的COD，优于单一光催化（SMX 100%，COD 4.2±0.74%）和单一生物降解（SMX 42.21±0.86%） , COD 95.1 ± 0.18%)。ICPB系统中SMX去除的贡献者从大到小包括LED光催化、生物降解、LED光解和载体的吸附作用，而COD去除主要归因于生物降解。增加初始 SMX 浓度会抑制 SMX 去除率，而增加光催化剂用量会加快 SMX 去除率，两者对 COD 去除率均无影响。Nakamurella和Raoultella是生物膜的两个主要属。这项工作为有效处理抗生素污染的生活废水提供了新的策略。