Effect of graphite felt and activated carbon fiber felt on performance of freshwater sediment microbial fuel cell

Background: Sediment microbial fuel cells (SMFCs) could be used as power sources and one type of new technology for the removal of organic matters in sediments. Various types of materials have been used as electrodes. Nevertheless, there is still room to improve electrode materials and enhance their effect on the performance of SMFCs. In this work, performances of SMFCs with activated carbon fiber felt (ACFF) and with nitric acid-treated ACFF were compared with graphite felt (GF) materials. Results: The maximum power density of the SMFC with ACFF electrode was the highest (33.5 ± 1.5 mW m ^-2). Nitric acid-treated GF electrode slightly increased the maximum power density of SMFC, while the nitric acid treated-ACFF resulted in significant decline in the maximum power density of SMFC. The maximum power density further increased to 74.5 ± 7.5 mW m ^-2 in SMFC using GF cathode and ACFF anode. Conclusions: ACFF as anode can enhance the transport of electrons from the oxidation of organic matter in the sediment, while the output power was found to reduce in SMFC with ACFF cathode. Further efforts are needed to study the formation conditions of the biocathode and new electrode modification technology.