Enhancing performance of microbial fuel cell by using graphene supported V2O5-nanorod catalytic cathode

[Display omitted] •In support with graphene (rGO), V2O5-NRs showed excellent ORR kinetics.•V2O5/rGO cathode enhanced power output with superior wastewater treatment in MFC.•Power density in MFC using V2O5/rGO was found higher than MFC with Pt-C cathode.•Cathode fabrication cost using V2O5/rGO catalyst was found much lower than Pt-C. Cathodes were fabricated around stainless steel wire mesh current collector, using vanadium pentoxide nanorods (V2O5-NRs) as catalyst supported with reduced graphene oxide (rGO) and Vulcan XC, for application in microbial fuel cell. Cyclic voltammetry analysis showed multiple redox current peaks of V2O5-NRs under applied potential range, revealing superior electrocatalytic activity. Power density enhanced from 384±45mW/m2 for MFC using V2O5/Vulcan XC cathode to 533±37mW/m2 for MFC using V2O5/rGO cathode; whereas MFC using catalyst free cathode fabricated with rGO and Vulcan XC produced significantly less power density of 95±9.9 and 75±7mW/m2, respectively. In addition, MFC using V2O5/rGO cathode demonstrated slightly higher power density than that obtained from MFC using 10% Pt-carbon cathode (512±51mW/m2). Coulombic efficiency and chemical oxygen demand removal of 37.5±1.36% and 85.02±1.46% in MFC using V2O5/rGO cathode was found to be highest among all MFCs. Noteworthy improvement in catalytic activity of low-cost V2O5-NRs catalyst enfolded with graphene is demonstrated, resulting in higher power output and organic matter removal in MFC. Higher power generated by MFC using low cost V2O5/rGO cathode, compared with costly platinum, makes it suitable option for scale-up of MFCs.