Preparation of High Contents of Pyridinic and Pyrrolic-Nitrogen Doped Activated-Carbon from Pyrolysis of Purple Cabbage for the Catalysis of Oxygen Reduction Reaction

Effective conversion of reproducible organic biomass into valuable carbon material is very important for renewable energy technology. In this study, here we develop a unique strategy to design a nitrogen-doped carbon-based electrocatalyst for oxygen reduction reaction (ORR) via successful pyrolysis of purple cabbage combining with ZnCl2 activation and acid-leaching processes. It is found that this carbon material show high ORR catalysis performance with an ORR onset potential of similar to 0.96 V versus RHE and a half-wave potential of similar to 0.8 V, slightly lower than that of the commercial Pt/C catalyst in 0.1 mol L--(1) KOH solution. The high ORR activity mainly derives from high contents of pyridinic- and pyrrolic-nitrogen inside the prepared carbon material. Besides, compared to the Pt/C catalyst, the prepared catalyst also exhibits excellent long-term stability, which can be considered as a promising carbon-based ORR catalyst for fuel cells.