Co and N co-doped porous carbon derived from corn stalk core as electrocatalyst for oxygen reduction reaction in alkaline medium

It is very essential to explore economical non-precious metal catalysts with high performance for the application of a mental-air battery. In this paper, using corn straw core (CSC) as raw material and KOH as activator, the obtained porous activated carbon (AC) with a high specific surface area (1209.1 m² g^-1) and suitable mesopore distribution (~3.8 nm) is prepared through high-temperature carbonization and activation process. The cobalt and nitrogen co-doped activated carbon (Co-N-C) catalyst is obtained by doping cobalt nitrate and urea into AC. The Co-N-C catalyst shows excellent electrocatalytic performance, and the half-wave potential of 0.736 V, the Tafel slope of 108.2 mV dec^-1, and the electron-transfer number of around 4 are achieved in 0.1 M KOH. The economic and practical biomass carbon derived from CSC is a kind of promising electrocatalyst for ORR in alkaline medium.