Synthesis of efficient electrocatalyst for oxygen reduction reaction by using poly(m-phenylenediamine) as the interlayer spacer and the sources of N-doped carbon and MnO

We report the facile synthesis of N-doped carbon-graphene-manganese oxide (N/C-G-MnO) that can serve as precious metal-free electrocatalysts for oxygen reduction reaction (ORR). The N/C-G-MnO is synthesized via polymerization of m -phenylenediamine adsorbed on graphene using KMnO 4 as the oxidant, followed by pyrolyzation of the resulting N- and MnO 2 -containing poly( m -phenylenediamine). That is, poly( m -phenylenediamine) plays multi-roles in the synthesis of the ORR catalysts: (i) Serving as interlayer spacer to prevent graphene sheets from restacking during the thermal annealing, (ii) Function as the source of N-doped carbon (N/C) and MnO for the simultaneous doping of graphene. The N/C-G-MnO exhibits better ORR activity, long-term stability and methanol tolerance than those of the commercial Pt (5%)/C catalyst.