(515g) Graphene Interfaced Geobacter for Improved Electron-Transport Channels in Microbial Fuel Cell: A Single Cell Investigation

With the increased interest in developing cost-effective and readily available energy sources, the research in the microbial fuel cell (MFC) field has gained an increased attention. Here, we report the use of graphene’s high electron mobility coupled with Geobacter sulfurreducens’ biocatalyst nature to increase the current response of a MFC. It is well-accepted that one of the limiting factors of current generation of a Geobacter based MFC is the electron transport process in the anodic chamber. We addressed this limitation by utilizing the enhanced electrical conductivity of graphene. In our preliminary tests, the current density of the MFC increased by 9 to 13 folds by interfacing Geobacter cells with graphene. To study the interface between graphene and Geobacter, Raman spectroscopy and scanning electron microscopy (SEM) were employed. The Raman characterization studies show that a single geobacter interfaced with graphene n-dopes it by about ~3 x 10¹² cm^-2. These results demonstrate that the graphene-Geobacter interface provides an approach to overcoming the electron-transfer related challenges of conventional MFCs.