Comparative Study for the Production of Sustainable Electricity from Marine Sediment Using Recyclable Low‐Cost Solid Wastes Aluminum Foil and Graphite Anodes

Abstract

AbstractThe influence of low‐cost anode materials, aluminum, and graphite on the sediment microbial fuel cell (SMFC) performance is investigated. The cathode in both cells is a high‐conductive pencil electrode. The open‐circuit potentials of the graphite sediment microbial fuel cell (CSMFC) and the aluminum sediment microbial fuel cell (ASMFC) are 600 mV and 1103 mV, respectively. The microbial metabolic activity in polluted marine sediment creates a large potential difference at the marine sediment/seawater interface. The sustainable electrical power from CSMFC and ASMFC are 680 mW.m−2 and 930 mW.m−2 respectively. The high cell potentials of both cells are achieved at ambient temperature. The designed SMFCs could power oceanographic instruments and biosensors in the coastal ocean. The total viable bacterial count (TVBC) and biological parameters of pore water are related to the high cell potential. The higher open‐circuit potential of ASMFC than CSMFC is mainly attributed to the lower charge transfer resistance of aluminum than graphite. This high performance is confirmed by using electrochemical impedance spectroscopy (EIS). The charge transfer resistance (Rct) of aluminum and graphite are 1600 and 2050 Ohm.cm2, respectively. The electrical conductivity of a thin film of aluminum and graphite are 40.1 104 and 9.99 103 Siemens/cm, respectively. The electrical resistivity of the ASMFC and CSMFC are 1.506×10−5 and 2.25661×10−5 Ω.m, respectively. These results strongly suggest that ASMFC has a higher electrical power density than CSMFC due to the lower charge transfer resistance, the good electrical conductivity of aluminum, and the lower electrical resistivity of ASMFC.