Electrochemical reduction of CO2 catalysed by Geobacter sulfurreducens grown on polarized stainless steel cathodes

Polarized stainless steel cathodes in pure cultures of Geobacter sulfurreducens generated reduction currents of up to 30A/m2 even when the sole electron acceptor contained in solution was completely reduced. It was shown here that these currents were driven by the carbon dioxide that was provided to the solution. It was postulated that CO2 reduction consumed succinate and produced glycerol, which remained stored inside the cells and was released under the effect of stress. [Display omitted] ► Geobacter sulfurreducens was grown on polarized stainless steel cathodes. ► The G. sulfurreducens biocathodes catalysed the reduction of fumarate into succinate. ► Currents of up to 30A/m2, driven by CO2, were evidenced. ► Succinate consumption was related to currents driven by CO2. ► Glycerol production was associated with the CO2 and succinate consumptions.