FeCu bimetallic metal organic frameworks photo-Fenton synergy efficiently degrades organic pollutants: Structure, properties, and mechanism insight.

[Display omitted] • FeCu bimetallic MOFs (FeCuBDC) were prepared by a solvothermal method. • FeCuBDC, H 2 O 2 and light constructed a novel photo-Fenton degradation system. • The synergistic system showed efficient degradation activity of organic pollutants. • High-valence FeCu captures e− and promotes photogenerated charge separation. • Low-valence FeCu decomposes H 2 O 2 and drives the bimetallic valence cycling. The high ion leaching, low photogenerated charge separation efficiency, and slow metal valence cycling of Fe-based metal organic frameworks (MOFs) have limited their application in the deep treatment of organic pollutants. Herein, FeCu bimetallic MOFs (FeCuBDC) were synthesized using a modified solvothermal method, and a coupled photo-Fenton degradation system was successfully constructed. Degradation performance tests showed that FeCuBDC could efficiently degrade 99.3% ± 0.1% of 50 mg/L phenol within 40 min. The reaction rate constants of the photo-Fenton system were 11.0 and 64.7 times higher than those of the single Fenton reaction and photocatalysis, respectively. FeCuBDC also exhibits good cycling stability, degradation generalization, and excellent photoelectric catalytic properties. Such a considerable enhancement in the overall performance pertains to the following. First, the introduction of Cu into Fe-MOFs not only improves the crystallinity and stability, but also reduces the band gap value, increases the absorption capacity of visible light, and promotes the generation of photogenerated carriers. Second, the FeCu in MOFs are all mixed valence. Initially, the high-valence FeCu captures photogenerated electrons and promotes photogenerated charge separation and transfer. Then, the low-valence FeCu adsorbs and decomposes H 2 O 2 , accelerating the valence cycling of the bimetallic sites. The core of the reaction mechanism is that FeCuBDC effectively promotes the photo-Fenton synergy. [ABSTRACT FROM AUTHOR]