Improving the Generation of Electricity and the Treatment of Wastewater in a Dual-Chambered Mediator-Less Microbial Fuel Cell
Microbial fuel cells (MFCs) may pose an inexpensive and effective solution to current environmental problems as they utilize anaerobic bacteria to simultaneously clean wastewater and generate electricity. MFCs, however, are not yet viable, because of their high costs and low power densities. This research begins to analyze how the anode composition and structure, the addition of multi-walled carbon nanotubes, and the type of bacteria used can improve the power output and wastewater treatment abilities of a MFC. To accomplish this, a variety of anodes with different compositions and shapes were used in the MFC while using Geobacter sulfurreducens or Shewanella putrefaciens as required anaerobic bacteria. The best performing anodes for each microbial community were then determined and coated with multi-walled carbon nanotubes in order to improve conductivity and provide more surface area. At the end of experimentation, a MFC operating with Geobacter and a nanomodified graphite rod anode reached a maximum power density of 1.8 W/m2, which is higher than the average power density achieved by most researchers. This result shows that incorporating specific nanomodified materials as anodes is a successful method of improving the performance of a MFC.