In situ formation of graphene/biofilm composites for enhanced oxygen reduction in biocathode microbial fuel cells

Here we reported a novel one-pot method for biocathode fabrication in microbial fuel cell (MFC), by which the microbially-reduced graphene was implanted into cathodic biofilm, leading to the in situ construction of graphene/biofilm composites with a three-dimensional structure. The maximum power density of the MFC with graphene-biocathode increased by 103% compared with the MFC with carbon cloth-biocathode. Electrochemical analyses showed that the graphene-biocathode had faster electron transfer kinetics and less internal resistance than the carbon cloth-biocathode. As an effective biocathode material, graphene/biofilm composites could enhance the electrocatalytic activity towards oxygen reduction, and facilitate the electron transfer between bacteria and electrode. (C) 2012 Elsevier B.V. All rights reserved.