A mesoporous carbon derived from 4,4′-dipyridyl iron as an efficient catalyst for oxygen reduction

Abstract

Developing highly active and low cost catalysts for oxygen reduction is crucial for the commercialization of advanced energy systems. In this work, a mesoporous carbon was fabricated through a simple pyrolysis procedure by using 4′4-bipyridyl, FeCl₃ and SBA-15 as the precursors and templates, respectively. The catalyst exhibits rather high ORR performance, with a half-wave potential of 0.906 V (vs. RHE). The catalyst also demonstrates outstanding stability, excellent methanol tolerance and high selectivity towards the four-electron path. The air electrode fabricated by using the catalyst can enable a zinc–air battery to deliver a specific capacity of 815.6 mA h g_Zn⁻¹ and a maximum power density of 196.3 mW cm⁻², which are among the highest values recently reported, to our knowledge. By comparing the catalysts obtained at different temperatures, we found that the increased graphitic N content together with the higher surface area should be the reasonable origins of the outstanding performance.