Printing specific active sites for ORR and hydrazine oxidation on N-doped carbon

Abstract

Among the prime challenges in clean energy research, the development of simple, cost-effective, and feasible strategies to prepare catalysts can be highlighted. As an alternative, herein N-doped carbonaceous catalysts were synthesized by the same cost-effective method, which can be used to produce both the anode and cathode of the fuel cell. The catalysts were obtained by pyrolysis of melamine-formaldehyde resins containing ions Cu2+, Co2+, or Ni2+ and used for oxygen reduction reaction (ORR) and hydrazine oxidation reaction (HzOR). Although the results prove that the activities for both reactions are derived exclusively from N-doped carbon moieties, the presence of some metal in the pyrolysis process is primordial to printing active sites on carbon structures. The catalyst obtained from Cu-based resin was superior regarding ORR, whilst that yielded from Co-based resin showed the best results for HzOR, indicating that the active sites generated for electroreduction and electrooxidation in each carbon structure are different. The best catalysts demonstrate ORR and HzOR activities very akin to the golden standard 20% Pt/C, presenting a ηonset values of 90 mV and 170 mV.