Photothermal-boosted effect of binary CuFe bimetallic magnetic MOF heterojunction for high-performance photo-Fenton degradation of organic pollutants

Highlights: • Bimetallic CuFe MOF was fabricated outside magnetic CuFe oxide via in-situ derivation strategy. • Photothermal effect of binary CuFe magnetic MOF catalyst can enhance the photo-Fenton activity towards POPs degradation. • Fe^III/Fe^II and Cu^II/Cu^I binary redox couples enhance the activity of catalyst. • MCuFe MOF works effcient with reduced H₂O₂ dosage and broaden the pH range. Overcoming the relatively low catalytic activity and strict acid pH condition of common photo-Fenton reaction is the key to alleviate the serious global burden caused by common organic pollutants. Herein, a binary homologous bimetallic heterojunction of magnetic CuFe₂O₄@MIL-100(Fe, Cu) metal-organic frameworks (MCuFe MOF) with photothermal-boosted photo-Fenton activity is constructed as an ideal practical photo-Fenton catalyst for the degradation of organic pollutants. Through an in-situ derivation strategy, the formed homologous bimetallic heterojunction with binary redox couples can simultaneously improve the visible light harvesting capacity and expedite the separation and transfer of photogenerated electrons/holes pairs, leading to the continuous and rapid circulation of both Fe^III/Fe^II and Cu^II/Cu^I redox couples. Notably, the heterojunction shows intrinsic photo-thermal conversion effect, which is found to be beneficial to boost the photo-Fenton activity. Impressively, MCuFe MOF shows remarkable catalytic performance towards the degradation of various organic pollutants by comprehensively increasing H₂O₂ decomposition efficiency and decreasing the required dosage of MCuFe MOF (0.05 g L⁻¹) with a wide pH range (3.0–10.0). As such, a photo-Fenton catalyst consisting of binary homologous bimetallic heterojunction is first disclosed, as well as its photothermal-enhanced effect, which is expected to drive great advance in the degradation of organic pollutants for practical applications.