An array of microliter-sized microbial fuel cells generating 100 μW of power

We report an array of three microliter-sized microbial fuel cells (MFCs) connected in series. The three MFCs were integrated into a sandwich of two glass slides, incorporating two chambers of 50 μL volumetric capacity that were separated by a cation exchange membrane (CEM). Each anolyte/catholyte chamber was defined by 500-μm thick PTEE (polytetrafluoroethylene) gaskets. The MFCs contained a Geobacter-enriched mixed bacterial culture and ferricyanide, which were independently driven into anolyte/catholyte chambers, respectively. The MFC array produced 100 μW total power (33 μW/cm2 or 667 μW/cm3) and 1.8 V output voltage, which are approximately 10 times and 4.5 times higher, respectively, than the maximum values of previously reported microliter-sized MFCs.