Development of high performance of Co/Fe/N/CNT nanocatalyst for oxygen reduction in microbial fuel cells

In this paper, we synthesized a unique cathode catalyst Co/Fe/N/CNTs with high performance oxygen reduction. Through the π-stacking force, the cobalt porphyrins (CoTMPP) and iron phthanlocyanine (FePc) were deposited to the carbon nanotubes (CNTs) sidewall. The CoTMPP/FePc functionalized CNTs were used as the precursor to prepare the Co/Fe/N/CNTs based oxygen reduction nanocatalyst through high-temperature pyrolysis. The as-prepared catalyst exhibited higher electrocatalytic activity for the reduction of dioxygen than that of the Co/Fe/N/graphite and commercial Pt/C. The high electrocatalytic activity and good stability for dioxygen reduction made the Co/Fe/N/CNT as a potential candidate for the efficient cathode material in microbial fuel cells (MFCs). The maximum power of the MFC using the Co/Fe/N/CNT as cathode catalyst is 751 mW m−2, which was 1.5 times larger than the MFC with the commercial Pt/C catalyst under the same condition. Such an approach is useful for the improvement of the cathode performance and to provide the basis for the development of the efficient MFC cathodes.