Fabrication of High-Performance MgCoO2/PEDOT:PSS@Nickel Foam Anode for Bioelectricity Generation by Microbial Fuel Cells

Abstract

We report the fabrication of cost-effective, biocompatible, and high-performance anode made of nickel foam (NF) modified with magnesium cobalt oxide (MgCoO2) and poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) as active components. Modified electrodes were prepared upon addition of each component to NF which formed PEDOT:PSS@NF, MgCoO2@NF, and MgCoO2/PEDOT:PSS@NF. These electrodes were compared for their electrocatalytic activity in dual-chambered microbial fuel cells (MFCs). Sewage wastewater was used as feed stock while exoelectrogenic microbes present in wastewater served to generate bioelectricity upon utilizing organic waste and glucose as an electron donor. The maximum power and current density values were found to be 494 mWm−2 and 900 mA m−2 using MgCoO2/PEDOT:PSS@NF anode. It was ~2.5 times higher than that of unmodified NF anode. Electrochemical impedance spectroscopy (EIS) analysis exhibited reduction in charge transfer resistance for MgCoO2/PEDOT:PSS@NF anode (25.26 Ω) compared to the unmodified NF anode (61.34 Ω). Thus, with the enhanced electrocatalytic activity and biocompatibility, MgCoO2/PEDOT:PSS@NF anode offered better stability and porosity for dense biofilm formation which helped in the efficient generation of bioelectricity.