2005-2006 Colloquium Series
NAU Physical Sciences (Bldg 19, Rm 321), Monday, December 5, 2005, 3:00 PM
(Refreshments at 2:45pm)
Microbal Fuel Cells: Power, Performance Factors and Microbal Physiology
Oriana Bretschger
University of Southern California
Dept. of Materials Science and Geobiology
NAU Physics & Astronomy Alumna
Abstract
Fuel cells are electrochemical systems that utilize chemical reactions to produce electricity. As long as fuel is supplied to the system the reactions will take place and electricity will result. Traditional fuel cells can use many fuels including hydrogen, methanol, natural gas and other hydrocarbons. These fuel cell systems typically require a precious metal catalyst at the electrode to drive the desired chemical reactions and produce electricity.
Microbial fuel cells (MFC's) utilize organic materials as fuel, microbes as catalysts and air as an oxidant for the production of electricity. Given these components, the electrical output of MFC’s has historically been much lower than that of traditional fuel cells, however work is being performed to increase the power output and efficiency of MFC systems so that in the future they may provide environmentally friendly, portable power. Present work has also shown that MFCs can function as bioremediation tools that treat waste water and yield a by-product of electricity! Additionally, MFC's are being applied as tools for understanding microbial physiology.
More knowledge must be gained about the microbe/electrode interaction to achieve and improve these MFC applications. Other MFC factors that also need to be considered include the type and number of microbes, type and quantity of fuel supplied to the MFC and MFC design. Preliminary work has indicated which microbes are best suited for MFC applications and the process of identifying the best fuel is underway. Additionally, several MFC designs have been engineered and others suggested that may improve power outputs. When these engineering and biological issues are fully understood and addressed MFC applications may only be limited by imagination!
Local Host: Dave Cornelison, (928) 523-7641.