Activated carbon nanofibers as promising low cost cathode for membraneless Single Chamber Microbial Fuel Cells (SCMFCs)

Microbial fuel cell (MFC) is a promising bio-technology capable of converting organic substances present in wastewater to electrical energy. MFC can lower high wastewater treatment costs and simultaneously produce clean electric energy. The major problems are the low power generation of MFCs and the usage of costly catalysts (e.g. Platinum (Pt)) for high cathodic reaction. The replacement of Pt with low cost, reliable, and effective cathodic catalysts is critical for scale-up MFC systems and real-world applications. In this study, novel cost-effective cathodes, carbon nanofibers (CN) and activated carbon nanofibers (ACN) were developed and compared with the traditional Pt-based cathodes in single chamber MFCs (SCMFCs). Materials characterization and electrochemical tests were performed. Linear Sweep Voltammetry (LSV) in PBS (phosphate buffer solution) showed better cathodic kinetic of the Pt-based cathode than CN and CAN cathodes, and the ACN cathodes had a greater performance than the CN. The advantage of the Pt-based cathode over ACN/CN cathodes steadily decreased over time, while the ACN/CN had stable performance over time.