Electricity generation from banana peels in an alkaline fuel cell with a Cu₂O-Cu modified activated carbon cathode

Low-cost and highly active catalyst for oxygen reduction reaction is of great importance in the design of alkaline fuel cells. In this work, Cu₂O-Cu composite catalyst has been fabricated by a facile laser-irradiation method. The addition of Cu₂O-Cu composite in activated carbon air-cathode greatly improves the performance of the cathode. Our results indicate the enhanced performance is likely attributed to the synergistic effect of high conductivity of Cu and the catalytic activity of Cu₂O towards the oxygen reduction reaction. Furthermore, an alkaline fuel cell equipped with the composite air-cathode has been built to turn banana peels into electricity. Peak power density of 16.12Wm^-2 is obtained under the condition of 3M KOH and 22.04gL^-1 reducing sugar, which is higher than other reported low-temperature direct biomass alkaline fuel cells. HPLC results indicate the main oxidation products in the alkaline fuel cell were small organic acids.