Performance of single-layer paper-based co-laminar flow microbial fuel cells.

This paper presents a novel design and operation of microbial fuel cells (ΜFCs), which contain monolayer paper-based substrate/electrodes and microchannels with co-laminar flow. The electrodes with multi-wall carbon nanotubes are fabricated by the screen-printing method and the microchannels are patterned using photo-lithography. A double-inlet and diverging channel design is incorporated in the fuel cell configuration and demonstrated significantly improved performance. The fluid flows of electrolytes through the porous paper media are simulated using steady-state and transient computational fluid dynamics The best performance is achieved under the following conditions: an electroactive microbial (S. oneidensis) concentration of OD 600 1.5, 50 mM electron donor (lactate), and direct immobilized of the inoculum on the anode surface. The developed MFCs achieves a peak power density of 19.4 ± 0.23 μW cm−2 and maximum current density of 190.4 ± 1.39 μA cm−2, surpassing the performance of all previously reported paper-based single MFCs that utilize paper-based electrodes. In addition, hybrid-type MFCs that containing enzymatic air-breathing cathodes are investigated to enhance their performance. The novel paper based self-pumping MFC has the potential to make lab-on-a-chip type portable medical diagnosis devices with integrated power sources practical and feasible. [Display omitted] • A paper-based membraneless co-laminar flow microbial fuel cell was developed. • Microfluidic fuel cell was micromachined as a monolayer structure in paper substrate. • Co-laminar flow of the electrolyte through paper was simulated using CFD analysis. • Inoculation method, anolyte type, and cell configuration were tested and optimized. • A hybrid microbial-enzymatic fuel cell was also examined for performance improvement. [ABSTRACT FROM AUTHOR]