Highly efficient caffeic acid induced copper photocatalyst for degrading antibiotics

• Caffeic acid induces the formation of a unique spatial structure. • Cu@CAF materials loaded with polyvalent copper were synthesized. • Cu 0 /Cu + /Cu 2+ synergistically enhances the photocatalytic activity . • The catalyst has excellent efficacy in the removal of quinolones and tetracycline . To address the increasingly severe issue of antibiotic contamination, a photocatalyst with a unique structure was synthesized via a one-step hydrothermal method using copper nitrate trihydrate as the precursor material. In this process, the induction effect of caffeic acid was utilized to facilitate the synthesis. The induction effect of caffeic acid was employed in this process. The performance of the photocatalyst in degrading antibiotic-contaminated wastewater under visible light was comprehensively evaluated. An in-depth analysis of the photocatalyst properties was carried out utilizing a variety of advanced characterization techniques. The study demonstrated that the incorporation of caffeic acid substantially enhanced the catalyst's sensitivity to visible light, thereby promoting the generation of reactive species essential for the degradation of antibiotics. Specifically, under visible light irradiation at concentrations of 40 mg·L⁻¹ and 0.5 g·L⁻¹, the removal efficiencies for tetracycline (TC) and ciprofloxacin (CIP) were 96.3 % and 92.9 %, respectively. Additionally, the experimental results indicate that the removal rates of levofloxacin (LOFX), ofloxacin (OFX), norfloxacin (NFX), tetracycline hydrochloride (TCH), chlortetracycline hydrochloride (CCH), and oxytetracycline (OTC) all exceeded 95.0 % within 2 h. In addition, the experimental results demonstrate that the catalyst exhibits superior performance across a range of pH levels, from acidic to alkaline environments, in contaminated river water, indicating a promising approach for real-world environmental applications.