Changes in Carbon Electrode Morphology Affect Microbial Fuel Cell Performance with Shewanella oneidensis MR-1

Abstract

Abstract:The formation of biofilm-electrodes is crucial for microbial fuel cell current production because optimal performance is often associated with thick biofilms. However, the influence of the electrode structure and morphology on biofilm formation is only beginning to be investigated. This study provides insight on how changing the electrode morphology affects current production of a pure culture of anode-respiring bacteria. Specifically, an analysis of the effects of carbon fiber electrodes with drastically different morphologies on biofilm formation and anode respiration by a pure culture (Shewanella oneidensis MR-1) were examined. Results showed that carbon nanofiber mats had ~10 fold higher current than plain carbon microfiber paper and that the increase was not due to an increase in electrode surface area, conductivity, or the size of the constituent material. Cyclic voltammograms reveal that electron transfer from the carbon nanofiber mats was biofilm-based suggesting that decreasing the diameter of the constituent carbon material from a few microns to a few OPEN ACCESSEnergies 2015, 8 1818 hundred nanometers is beneficial for electricity production solely because the electrode surface creates a more relevant mesh for biofilm formation by Shewanella oneidensis MR-1.

Characterization of OmcA Mutants from Shewanella oneidensis MR‐1 to Investigate the Molecular Mechanisms Underpinning Electron Transfer Across the Microbe‐Electrode Interface

“…Carbon based electrodes of different natures are being proposed for biotechnological applications of organisms such as SOMR‐1 . This is a consequence of their chemical and biological inertness in the operating conditions of microbial electrochemical technologies, and their potential for being cheap to produce.…”

Evolving Microbial Communities in Cellulose-Fed Microbial Fuel Cell

“…The abundance of Clostridia here in the inoculum and after operation was sustained on the level 10%, but this genus was not the most abundant in the anodic microbial population. However, it has been noted that ability of microorganisms to produce high power densities does not necessarily correlate with their high abundance in the anodic biofilm [61], as abundances can be affected by biomass yields and other factors [62,63].…”

Influence of carbon anode properties on performance and microbiome of Microbial Electrolysis Cells operated on urine

“…6). Sigmoidal shaped voltammograms were observed for all anodes suggesting that the current was produced by direct electron transfer from the biofilm [42]. Torres and co-workers demonstrated that the electroactive microorganisms that grown at low anode potentials (-0.150 V vs SHE) carried out extracellular electron transfer exclusively by conducting electrons through the biofilm [38].…”