Evaluation of Order Mesoporous Carbon as Anode Catalyst for Microbial Fuel Cells Applications

Abstract

Ordered Mesoporous Carbon (OMC) was evaluated as anode catalyst in a MFC. Bacilus subtilis (B. subtilis) was the microorganism, while the electrolyte was Pharmaceutical Residual Water (PRW). In a dual chamber MFC, the anode and cathode compartments contained N2–saturated PRW and O2–saturated KOH (both electrolytes with pH=9.6), respectively, separated by a Nafion® membrane. The anode catalysts on gas diffusion electrodes in the MFC were: methanol-functionalized OMC, non-functionalized OMC, methanol-functionalized Vulcan XC-72 and commercial Pt/C, all covered by a biofilm of B. Subtilis. Meanwhile, the cathode catalyst was Pt/C. Significantly higher catalytic activity was obtained from functionalized OMC + B. Subtilis in the MFC. The Open Circuit Voltage (OCV) was 0.58 V, with a maximum current density (jcell) of 854 mA m-2. These values were 2.6 and 4.7 times higher than those from Pt/C. The results showed that methanol-functionalized OMC is a metal-free catalyst with high performance for MFCs.