A sustainable photocatalytic fuel cell integrated photo-electro-Fenton hybrid system using KOH activated carbon felt cathodes for enhanced Amaranth degradation and electricity generation

Photo-electro-Fenton (PEF) process was integrated with photocatalytic fuel cell (PFC) through the connection of electrodes and the cathodes were responsible for the acceptance of electrons. In this study, potassium hydroxide (KOH) was used to activate the carbon felt (CF) to improve the oxygen reduction reaction reactivity on cathodes for effective PFC integrated PEF hybrid system (PFC-PEF system) in Amaranth removal and electricity generation simultaneously. The results revealed that KOH activated CF cathodes had improved the electro-generation of hydrogen peroxide in both PFC and PEF and contributed to decolourisation efficiencies of 99.25% (PFC) and 96.10% (PEF). The maximum power density (4.218 mu W cm-2) achieved by KOH activated CF cathode was 22% higher than that of pristine CF. The results revealed that air flow rate of 1000 mL min-1 favoured the generation of more reactive species for effective Amaranth degradation under the dissolved oxygen enrichment condition. The highest decolourisation rates were respectively achieved in PFC (0.5965 h-1) and PEF (0.2919 L mg-1 h-1) at air flow rate of 1000 mL min-1.

Automated summary

The photo-electro-Fenton (PEF) process was combined with the photocatalytic fuel cell (PFC) to remove Amaranth from water and generate electricity simultaneously. The activation of carbon felt (CF) cathodes using potassium hydroxide (KOH) improved the efficiency of oxygen reduction reaction and decolourisation. The results showed that KOH activated CF cathodes increased the electro-generation of hydrogen peroxide and achieved higher power density compared to pristine CF cathodes.