A Reasonable Design of MnCo2S4 and Activated Carbon Composite as Cathode Catalyst to Improve the Power Output of Microbial Fuel Cells

The output power and combination property of microbial fuel cells (MFCs) are often limited by the sluggish kinetics of the cathodic oxygen reduction reaction (ORR). Therefore, seek noble metal-free materials with good ORR catalytic efficiency and durability is of great significance for practical MFC application. In this paper, ternary transition metal sulfide was successfully loaded on activated carbon by hydrothermal method. In the MnCo2S4@AC nanocomposite, the synergistic effect existing between MnCo2S4 and activated carbon (AC) gives the advantages of large specific surface area, special microstructure, fast electron transmission rate and good electro-catalytic activity of MnCo2S4 for ORR. The electrochemical tests showed that the ORR event of MnCo2S4@AC was the four-electron (4e-) pathway. Therefore, the highest output power density of MFC assembled with MnCo2S4@AC was 239.41 mW m(-2), 3.59-fold stronger than AC (66.66 mW m(-2)). This method can provide the ideas for the synthesis of efficient ORR catalyst.