Construction of a novel Cu2(OH)3F/Cu2O n-p heterojunction by in-situ reduction: photo-Fenton-like synergistic promotion of efficient Cu2+/Cu+ cycling

Cu-based Fenton-like systems have demonstrated high effectiveness in the degradation of organic pollutants, however, challenges still exist to overcome the sluggish cycling of metal ions and fast activation of reactants. Herein, a novel n-p type Cu₂(OH)₃F/Cu₂O photo-Fenton-like catalyst (CFC) was prepared with in-situ reduction of Cu₂(OH)₃F and applied for tetracycline hydrochloride degradation. Under optimized condition, the target catalyst (CFC-5) showed excellent activity, achieving a degradation efficiency of approximately 99.93 % in 30 min. The reaction rate constant with CFC-5 was 4.10 and 3.26 times higher than that of Cu₂(OH)₃F and Cu₂O, respectively. Moreover, the Cu₂(OH)₃F/Cu₂O catalyst exhibited highly cycling stability and broad applicability. The results illustrate that construction of Cu₂(OH)₃F/Cu₂O composites facilitates the charge separation and enhances Cu²⁺/Cu⁺ cycling, which benefits the generation of highly oxidizing active species and thus significantly improved the degradation efficiency. Besides, this study offers a versatile method to construct inexpensive and efficient photo-Fenton-like heterojunction catalysts.