NiCo2O4-graphene nanocomposites in sugar industry wastewater fed microbial electrolysis cell for enhanced biohydrogen production

Hydrogen energy from real-time effluents by Microbial Electrolysis Cell (MEC) has gained intense research interests. Especially, material development for both electrodes and catalysts not only influence the performance but also the overall process economy. In this study, the cathode employed was Nickel foam (NF) modified with synthesized catalyst of NiCo2O4-graphene nanocomposites in MEC operated with sugar industry wastewater. NiCo2O4-graphene nanocomposites decorated NF exhibited an excellent performance in terms of hydrogen production rate 0.14 ± 0.003 L/L D−1, which was 3.2 times higher than control NF at the optimized conditions. Electrochemical Impedance Spectroscopy reflected the improved catalytic performance of the nanocomposites 1.6-fold enhancement over control. The improved performance was reported as Coloumbic efficiency 66.2%, Cathodic hydrogen recovery 27.9%, Overall hydrogen recovery 18.4% and COD removal efficiency 58.1% respectively. Hence, suitability of novel catalyst was investigated demonstrating better results of modified cathode with bio-catalyzed anode employed in industrial effluent.