Article

Electricity Generation by Geobacter sulfurreducens Attached to Gold Electrodes

Departments of Microbiology and Chemistry, University of Massachusetts-Amherst, MA 01003, USA.
Langmuir (Impact Factor: 4.46). 05/2008; 24(8):4376-9. DOI: 10.1021/la703469y
Source: PubMed

ABSTRACT

The versatility of gold for electrode manufacture suggests that it could be an ideal material for some microbial fuel cell applications. However, previous studies have suggested that microorganisms that readily transfer electrons to graphite do not transfer electrons to gold. Investigations with Geobacter sulfurreducens demonstrated that it could grow on gold anodes producing current nearly as effectively as with graphite anodes. Current production was associated with the development of G. sulfurreducens biofilms up to 40 microm thick. No current was produced if pilA, the gene for the structural protein of the conductive pili of G. sulfurreducens, was deleted. The finding that gold is a suitable anode material for microbial fuel cells offers expanded possibilities for the construction of microbial fuel cells and the electrochemical analysis of microbe-electrode interactions.

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    • "The main drawback of these materials is their smooth surface that hinders the adhesion of the bacteria. This is why several non-corrosive metals, such as stainless steel [30], titanium [3] [47] or gold [121], failed to achieve higher power densities than carbon materials [153]. Some modifications based on increasing the anode surface have been developed to solve this problem, facilitating the adhesion of the bacteria and electron transfer to the anode, thereby improving power production. "
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