A new approach for in situ cyclic voltammetry of a microbial fuel cell biofilm without using a potentiostat.
Electrochemically active bacteria in a microbial fuel cell (MFC) usually exist as a biofilm attached to an electrode surface. Conventional cyclic voltammetry using potentiostat is considered as a powerful and reliable method to study electrochemical behavior of MFC biofilm. In this paper, we introduce a new approach to evaluate redox behavior of an electro-active MFC biofilm without using a potentiostat. Analogous to a conventional cyclic voltammetry study, we controlled the biofilm-electrode potential by computer-feedback controlling the external resistance of an operating MFC. In this way, the MFC can still operate as a "fuel cell" without being "interrupted" by an external device (i.e. potentiostat) that normally does not belong to the system. Relationship between current and biofilm-electrode potential was obtained and showed agreement with a potentiostat-controlled method under similar experimental conditions. The method could be added to our technical repertoire for analysis of bacterial mediator involved in the exocellular electron transfer of a MFC-biofilm, and it could potentially serve as a practical process monitoring method for MFC operation. The application of computer-control components should be further explored to facilitate control, diagnosis as well as optimization of MFC processes.
Cheng
Ka Yu
KY
Faculty of Sustainability, Environment and Life Sciences, Murdoch University, WA 6150, Australia. k.cheng@murdoch.edu.au
Cord-Ruwisch
Ralf
R
Ho
Goen
G
D001674:Bioelectric Energy Sources; D018441:Biofilms; D004563:Electrochemistry / Q000295:instrumentation; D004566:Electrodes; D004867:Equipment Design; D010084:Oxidation-Reduction