Co-laminar Microfluidic Microbial Fuel Cell Integrated with Electrophoretically Deposited Carbon Nanotube Flow-Over Electrode

Abstract

This study reports the development of a co-laminar flow microbial fuel cell (MFC) with single-walled carbon nanotube (SWCNT) electrodes microfabricated by electrophoretic deposition. The effects of the flow channel height and the shear stress at the anode biofilm on the power density and the fuel utilization rate of the co-laminar flow MFC were investigated to improve the MFC’s performance. The power density and the current density increase with increasing channel height, while the flow rate is kept constant. Meanwhile, when the flow rate was also adjusted according to the channel height to yield the optimum shear stress for biofilm formation, the performance improved further, but fuel utilization decreased. The maximum measured power density (143 ± 1 μW cm−2 ) of the developed MFC is better than those of microfabricated metal-based electrode MFCs. This micromachined, carbon-based, flow-over electrode improves the MFC’s performance and enables mass production of MFCs integrated with planar microdevices based on the microelectromechanical system process.