Templating Synthesis of Mesoporous FeC-Encapsulated Fe-N-Doped Carbon Hollow Nanospindles for Electrocatalysis.

Developing cost-efficient alternatives to the noble metal catalysts toward oxygen reduction reaction (ORR) has attracted much attention. Herein, a kind of mesoporous hollow spindlelike Fe-N-C electrocatalysts with iron carbide nanoparticles encased in the N-doped graphitic layers has been synthesized by a novel "reactive hard template" strategy through the Fe-assisted polymerization of dopamine on the FeO cores and the following calcinations. The FeO nanospindles not only as the hard template guide the formation of well-defined shape and structure of the catalyst but also as the reactive template provide Fe reservoir to generate FeC nanoparticles in the catalyst during the thermochemical process. The superiority in accessible active sites of Fe-N species, FeC nanoparticles in graphenelike layers, and highly mesoporous hollow structure enables the catalysts to exhibit excellent ORR performances including high catalytic activity, outstanding long-term cycling stability, and good tolerance to methanol.