Co_0.85Se/Multi-Walled Carbon Nanotube Composite as Alternative Cathode Catalyst for Microbial Fuel Cells

The development of low-cost and high-performance cathode catalyst remains a great challenge for constructing large-scale microbial fuel cells (MFCs). Here, the multi-walled carbon nanotube (MWCNT) supported cobalt selenide (Co_0.85Se) composite was synthesized by a simple and effective hydrothermal process for the first time. Compared with uncomposited electrodes such as MWCNTs and Co_0.85Se, the as-prepared Co_0.85Se/MWCNT composite electrode exhibited significantly improved electrochemical performance and durability. The maximum power density of Co_0.85Se/MWCNT composite electrode is 243.6 mW m^–2, which is 12.2 fold higher than that of unmodified electrode and more than twice as much as those observed for MWCNTs cathode (114.1 mW m^–2) and Co_0.85Se cathode (119.8 mW m^–2). This work may provide not only the fundamental studies on carbon supported transition-metal selenide but also a new kind of promising alternative electrode in the technology of power generation from MFCs.