title: A new approach for in situ cyclic voltammetry of a microbial fuel cell biofilm without using a potentiostat.
abstract: 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.
authors.affiliation: Faculty of Sustainability, Environment and Life Sciences, Murdoch University, WA 6150, Australia. k.cheng@murdoch.edu.au
authors.forename: Ka Yu
authors.initials: KY
authors.lastname: Cheng
authors.forename: Ralf
authors.initials: R
authors.lastname: Cord-Ruwisch
authors.forename: Goen
authors.initials: G
authors.lastname: Ho
mesh_terms: D001674:Bioelectric Energy Sources; D018441:Biofilms; D004563:Electrochemistry / Q000295:instrumentation; D004566:Electrodes; D004867:Equipment Design; D010084:Oxidation-Reduction