Graphene modified electrodes for bioelectricity generation in mediator-less microbial fuel cell

The present study comprises a facile and economical way of modifying carbon cloth anodes with electrochemically reduced graphene oxide employing dip coating method followed by electrochemical reduction technique without using any reducing agent. The physical characterization and validation of formation of electrochemically reduced graphene oxide and graphene oxide is accomplished using X-ray diffraction and Raman spectroscopy techniques. Electrochemical properties of electrodes are assessed using cyclic voltammetry and electrochemical impedance spectroscopy, which indubitably support higher charge storing capacity and lower charge transfer resistance in electrochemically reduced graphene oxide electrodes. Electrochemically reduced graphene oxide exhibits 17.5- and 8.75-times higher power density as compared to carbon cloth and graphene oxide, respectively. Synergistic effect of the large surface area for bacterial colonization and high conductivity of electrochemically reduced graphene oxide is responsible for its superior performance in a microbial fuel cell. The present work demonstrates power production with a cost-effective microbial fuel cell reactor configuration having graphene-based electrode as an anode, economic stainless steel as a cathode, inoculated with mixed culture and mere deionized water as catholyte, and such setup is essential for scaling up of microbial fuel cell to commercialization.