IL-derived N, S co-doped ordered mesoporous carbon for high-performance oxygen reduction

Abstract

A highly efficient N, S co-doped porous carbon ORR catalyst was simply designed in our report from ordered mesoporous carbon (OMC) and trace ionic liquids (ILs). The microstructure OMC was chosen as the template for improving the specific area, confining the ILs in the mesopores, and promoting the formation of the planar N and S doping. The resulting IL/OMC (IOMC) nanostructure exhibits comparable ORR activity and better stability than the commercial Pt/C catalyst in 0.10 M KOH solution, which makes it one of the best-performing metal-free carbon ORR catalysts. We deduced that the excellent ORR activity is attributed to the synergistic effect of N, S, and the ordered mesoporous structure. Interestingly, the ORR activity can be further boosted in both basic and acidic solutions after Fe doping into the IOMC nanostructures which clearly emphasizes that transition metal Fe is important for the construction of ORR active functional sites especially in acidic solution.