Long-term effect of set potential on biocathodes in microbial fuel cells: Electrochemical and phylogenetic characterization

► The long-term effect of set potential on oxygen reducing biocathode was studied. ► 60 mV vs. SCE is the optimum potential to get a high electrochemical performance. ► A period of 40-60 days is needed for biocathode regulation to get a mature biofilm. ► Potential impacts the specific electrochemical activity rather than biomass amount. ► Potential has a strong selection for cathode bacteria.