Multi-cathode photocatalytic fuel cell with rotating bamboo charcoal electrodes for electricity production and simultaneous organic pollutants removal

Abstract

Carbonaceous materials have considerable potential as effective cathode catalysts due to their low cost and high oxygen reduced reaction (ORR) activity. However, current approaches face significant challenges, such as the fall-off of the catalyst and mass transfer inhibition as the catalyst loading increases. In this study, a multi-cathode-based photocatalytic fuel cell (PFC) was developed for maintaining a high cathode catalyst loading and simultaneously enhancing the mass transfer to improve the catalytic activity. Under identical high loading, the cathode configuration would significantly influence the power production of the PFC. The maximum power of the multi-cathode PFC was 50% and 53% higher than those of the Pt cathode and single-cathode PFCs, respectively. Meanwhile, the removal efficiency of methyl orange (MO) in the multi-cathode PFC was also higher than that in the single-cathode PFC. These results were attributed to the relatively large effective area and reduced transfer resistance of electrons and oxygen, owing to the multi-cathode system. In addition, a batch of experiments involving different parameters (such as pH, rotating speed, and initial MO concentration) was performed to obtain the optimal parameter conditions. Considering the high cost of Pt, all the tests indicated that the PFC with the multi-cathode configuration efficiently enhanced the power generation and simultaneously facilitated the removal of organic pollutants.