Superiority of activated graphite/CuO composite electrode over Platinum based electrodes as cathode in algae assisted microbial fuel cell

This study involves development of a low-cost cathode catalyst suitable for algae-based microbial fuel cell (MFC) application. The electrodes comprise of nanoparticles (NPs) of CuO/MnO2/Fe3O4 mixed with activated graphite. The study compares the performance of composite electrodes with Pt coated C-cloth. The graphite/CuO supported highest power & current density, algal growth, and electrocatalytic activity while Pt/C electrode failed in all aspects as algae ceased to grow in the system. The graphite/CuO cathode led to 6 W/m3 of power density, 25 A/m3 of current density, and 0.256 d−1 as a specific algal growth rate. The composite graphite/CuO electrode showed better catalytic activity towards oxygen reduction reaction (ORR) in the cathode. Furthermore, the Pt was found out to be toxic for the algal growth. Hence, the Pt-MFC exhibited low power output due to failure of cathodic algal growth. In addition to this, the GC–MS analysis of FAME (Obtained from cathodic algae) revealed the optimum presence of both saturated and unsaturated fatty acids, indicating its suitability for biodiesel application.