Energy-efficient mineralization of perfluorooctanoic acid: Biomass energy driven solar photo-electro-fenton catalysis and mechanism study

The smart eco-friendly biomass energy driven electrical degradation system was established by coupling of glucose fuel cells (GFC) and solar photo-electro-Fenton (SPEF) processes, which was proposed for the green, economical and efficient degradation of perfluorooctanic acid (PFOA). The CoFe alloy nanoparticles with oxygen defects (O*) based on metal–organic frameworks (MOFs) were decorated on polyacrylonitrile (PAN)-driven carbon nanofiber (CNF) membrane to obtain the bifunctional photocathode ([email protected]) with both extraordinary photo-catalytic and electro-catalytic abilities. PFOA was highly mineralized on [email protected] through the synergy of photocatalytic oxidation and electro-Fenton processes. Moreover, the energy consumption for degradation was generated from direct electro-oxidation of glucose as the clean power on anode (GFC). The possible mechanism and degradation pathway for PFOA mineralization was investigated in detail according to intermediate analysis, active species verification and the valence state change of Co and Fe on cathode. Besides, the toxicity evolution during PFOA degradation was also evaluated to deeper insight into risk assessment of intermedia products and relative toxicity, intending to prove the potential for practical elimination of PFOA and other toxicity recalcitrant pollutants in wastewater by GFC-SPEF system.