John R. Varcoe

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Microbial fuel cells (MFCs) represent a clean and renewable energy resource. To date, power generation in MFCs is severely limited. In order to improve performance, a wide range of techniques have been utilised for a fundamental scientific understanding of the components and processes and also to investigate MFC performance bottlenecks. In this tutorial(More)
The construction and characterization of a one-compartment fructose/air biological fuel cell (BFC) based on direct electron transfer is reported. The BFC employs bilirubin oxidase and d-fructose dehydrogenase adsorbed on a cellulose-multiwall carbon nanotube (MWCNT) matrix, reconstituted with an ionic liquid, as the biocathode and the bioanode for oxygen(More)
Insights into extracellular electron transfer of microorganisms are important for the understanding of electron transport processes in bioelectrochemical systems (e.g. biological fuel cells and microbial electrolysis cells), as well as for biogeochemical cycles, biocorrosion and bioremediation. Two principal mechanisms for extracellular electron transfer(More)
This article presents the first systematic study of the effect of Relative Humidity (RH) on the water content and hydroxide ion conductivity of quaternary ammonium-based Alkaline Anion-Exchange Membranes (AAEMs). These AAEMs have been developed specifically for application in alkaline membrane fuel cells, where conductivities of >0.01 S cm(-1) are(More)
The aqueous polymer poly(vinylbenzyltrimethylammonium chloride), PVBTMACl, solution (30.22% mass, MW = 400,000, Scientific Polymer Products, Inc., USA) was diluted with ethanol (ethanol:water = 1:1 by volume) and mixed with the commercially available electrocatalyst, HiSpec4000 containing 40%(mass)Pt/C (Johnson Matthey, UK), to form a catalytic ink(More)
A microbial fuel cell (MFC) has been developed for removal of sulfur-based pollutants and can be used for simultaneous wastewater treatment and electricity generation. This fuel cell uses an activated carbon cloth+carbon fibre veil composite anode, air-breathing dual cathodes and the sulfate-reducing species Desulfovibrio desulfuricans. 1.16gdm(-3) sulfite(More)
By employing the sulfate-reducing bacterium Desulfovibrio desulfuricans we demonstrate the possibility of electricity generation in a microbialfuel cell (MFC) with concomitant sulfate removal. This approach is based on an in situ anodic oxidative depletion of sulfide produced by D. desulfuricans. Three different electrode materials, graphite foil (GF),(More)
The spatiotemporal development of a bacterial community in an exoelectrogenic biofilm was investigated in sucrose-fed longitudinal tubular microbial fuel cell reactors, consisting of two serially connected modules. The proportional changes in the microbial community composition were assessed by polymerase chain reaction–denaturing gradient gel(More)
This article introduces the radical approach of applying alkaline anion-exchange membranes (AAEMs) to meet the current challenges with regards to direct methanol fuel cells (DMFCs). A review of the literature is presented with regards to the testing of fuel cells with alkaline membranes (fuelled with hydrogen or methanol) and also to candidate alkaline(More)