Activation of peroxymonosulfate by Cu0/CuFeO2 composite for tetracycline hydrochloride degradation with free radical and non-radical multi-pathways

The widespread use of tetracycline has made the efficient and environmentally friendly treatment of tetracycline-contaminated wastewater a pressing issue in environmental management. This study synthesized high-purity and uniformly mixed Cu 0 /CuFeO 2 composite materials using a one-step hydrothermal method, aiming to enhance the catalytic activation of peroxymonosulfate (PMS) through the synergistic effect of zero-valent metal and bimetallic compounds. The Cu 0 /CuFeO 2 composite demonstrated exceptional PMS activation performance, achieving 84% tetracycline hydrochloride (TCH) degradation within 1 min and 91% degradation within 20 min. The degradation process involved the synergistic action of •OH, SO 4 •− , 1 O 2 , and electron transfer. The degradation intermediates of TCH were identified using high-performance liquid chromatography–mass spectrometry (HPLC-MS), and four potential degradation pathways were proposed. Furthermore, Cu 0 /CuFeO 2 exhibited robust degradation performance across a wide pH range and maintained high efficiency in complex aqueous environments. Even after five cycles, the composite retained 78% of its degradation efficiency, demonstrating excellent stability and reproducibility in the degradation of TCH using the Cu 0 /CuFeO 2 /PMS system. Practitioner Points A high-purity and uniformly mixed Cu 0 /CuFeO 2 composite was synthesized. Robust catalytic activity and stability was observed for the synthesized catalyst. Synergistic contributions from •OH, SO 4 •− , 1 O 2 , and e − resulted in TCH degradation. Four potential TCH degradation pathways were derived. Graphical A Cu 0 /CuFeO₂ composite was synthesized, characterized, and optimized to activate peroxymonosulfate (PMS) for degrading tetracycline hydrochloride (TCH) and related antibiotics. In this system, Cu 0 acted as an electron donor, facilitating electron transfer through the redox cycling of metal ions. This process sustained the continuous generation of reactive oxygen species—including •OH, SO₄•⁻, and ¹O₂—as well as electrons, thereby promoting the efficient degradation of TCH. Furthermore, four potential degradation pathways were proposed based on the identified degradation intermediates.