Enhanced photo-electro-Fenton degradation performance using graphene structure-oriented MOFs (2Fe/Co)/CNF cathode membrane

Difficulties in mineralizing organic dyes and antibiotics have been bottlenecks limiting wastewater treatment technology development. Electrocatalytic advanced oxidation through selective two-electron oxygen reduction on cathodes is a promising method of mineralizing organic wastewater. However, most developed cathodes cannot efficiently synthesize H2O2 in situ via 2e− pathways and their durability cannot be guaranteed due to Fe2+ leaching. Therefore, the electrospun cathode (MOFs (2Fe/Co)/CNF) with both photocatalytic and electrocatalytic functions was ingeniously fabricated for efficient degradation of dyes and antibiotics through graphene template effect, carbonization and in-situ growing strategies. On the cathode surface, H2O2 was continuously generated in situ via 2e− reduction reactions, activating Fenton-like reactions. In addition, the developed cathode (MOFs (2Fe/Co)/CNF) had a low band gap (1.32 eV), which enhanced visible light response and improved catalytic active sites of the cathode. Degradation experiments of methylene blue and erythromycin solution indicate that the developed cathode showed excellent synergistic photoelectrocatalysis performance. In a photo-electro-Fenton system (PEF), the mineralization rate of methylene blue and erythromycin reached 86.5% and 90.2% within 10 and 30 min, respectively. The cathode in this research is expected to have great potential to efficiently mineralize wastewater via PEF.