Improved Cathodes for Microbial Fuel Cells

Organic waste generation including domestic wastewater food industry waste and animal waste is a large problem in the United States. It is estimated that domestic wastewater generation alone is roughly 150 gallons per person per day. There have been many proposed solutions for organic wastewater treatment with Microbial Fuel Cells (MFCs) providing a tremendous opportunity for sustainable treatment of organic wastewater and conversion to electrical power. However cathodic potential losses in current MFCs may be greater than 0.5 V making the overall efficiency too low for efficient scalability and subsequent commercialization. Researchers at the Biodesign Institute of Arizona State University have developed a novel solution to the issue of cathodic potential losses. It includes replacement of traditional Nafion binder in cathodes. This may increase MFC voltage by > 0.15 V thereby resulting in power densities up to 90% more than currently observed MFCs. Comparative experiments show that the replacement binder alone outperformed traditional Nafion binders by >100 mV demonstrating enhanced OH- transport. This novel solution involving the replacement binder with its ability to overcome cathodic limitations may be the key to successfully scale up and commercialize MFCs. Potential Applications: 1) Domestic wastewater treatment 2) Animal waste treatment 3) Food industry waste treatment 4) Biomass power generation