Rice Husk-Activated Carbon for Fabricating the Electrodes of Microbial Fuel Cell: An Examination of the Effectiveness of PTFE Binder

To increase concerns over depleting fossil fuel energy, global warming, and environmental pollution, researchers worldwide exploit new sustainable and environmentally-friendly energy resources. Microbial fuel cells (MFCs) that can harvest energy from organic wastes through microbial metabolism have attracted attention in recent decades. In this study, we report on the application of high surface area-activated carbon derived from rice husks for the electrodes. Rice husk appears to be a promising source of carbon material for fabricating MFC cathodes and anodes because of its abundance, carbon–neutral property, and low cost. Identifying low-cost materials and efficient electrode architectures is important for improving the cost-effectiveness and performance of MFCs. Carbon-based materials are most frequently used as both anodes and cathodes. The anode was made of rice husk charcoal by attaching to a 2 cm × 2 cm steel mesh. In addition, the cathode was fabricated of a mixture of rice husk charcoal and polytetrafluoroethylene (PTFE) with a weight ratio of 8:2. After the rice husk charcoal and PTFE solution mixture formed a paste, it was put into bag-shaped steel mesh using and then pressed for 20 min at room temperature. PTFE has excellent electrical properties. PTFE was used for the purpose of improving conductivity. To confirm the effectiveness of the PTFE binder, we also prepared cathodes with rice husk charcoal only. It can be confirmed that the PTFE binder effectively improves the amount of power generation and long-term stability.