Performance Assessment of Co-MnO2/C Cathodic Catalyst in Pipe-Type Microbial Fuel Cells

Cobalt ion intercalated MnO2 on carbon black (Co-MnO2/C) is a promising low-cost catalyst for improving the air-cathode performance in microbial fuel cells (MFCs). This research focused on assessing the performance of the Co-MnO2/C catalyst used in the cathode of a pipe-type MFC, which had both the anode and cathode placed inside wastewater. Co-MnO2 was synthesized by the redox reaction of cobalt nitrate hexahydrate and potassium permanganate in aqueous conditions, and then carbon black was added to the result solution. The catalyst was separated from the solution by centrifugation and drying processes. The catalyst was mixed with a carbon-based ink binder to fabricate the cathode. In addition, a control cathode without the catalyst was used for comparison. Experimental results showed that the cathode with the catalyst generated much higher output voltage and power than the control cathode. Although the cathodes worked in low-oxygen diffusion conditions, the cathode with the catalyst generated significant output with a maximum power density of 76 mW/m2.