Extracellular Electron Transfer on Sticky Paper Electrodes: Carbon Paste Paper Anode for Microbial Fuel Cells

Carbon paste paper electrodes (CPPEs) were fabricated by coating a regular paper strip with carbon paste made from graphite powder and mineral oil, followed by coating with polyaniline. The CPPEs were evaluated as anodes in bioelectrochemical cells (BECs) using Shewanella oneidensis MR-1 as bacteria that donate electrons through extracellular electron transfer. The CPPE was compared to a carbon felt electrode (CFE) modified with polyaniline under the same conditions. The BEC using the CPPE anode produces current continuously for at least 4 days without the need for additional fuel (lactate). Twenty-four hours after inoculation, the BEC using the CPPE anode generates a current density more than two times greater than that of the cell using the CFE, with a competitive maximum value of 2.2 A m^–2. The simple fabrication, ease of modification, and low cost of the CPPE make it a promising new bioelectrode material for microbial fuel cells