Nitrogen\nand Sulfur Dual Self-Doped Graphitic Carbon\nwith Highly Catalytic Activity for Oxygen Reduction Reaction

Abstract

The use of heteroatom-doped\ncarbon materials in the oxygen reduction\nreaction (ORR) continues to be an attractive alternative to Pt-based\ncatalyst. In this work, nitrogen and sulfur dual self-doped hierarchically\nmicro- and mesoporous graphitic carbon catalyst was prepared by pyrolysis\nof methyl orange (Fe (III)) complex, followed by removing the metal\nspecies in acid. The catalyst shows high electrocatalytic activity,\nlong-term stability and tolerance for methanol in both acidic and\nalkaline media. Especially, the catalyst exhibits superior ORR electrocatalytic\nactivity than that of the commercial Pt/C (20 wt %) in 0.1 M KOH:\n0.962 and 0.865 V (vs RHE) of onset and half-wave potential was obtained,\nwhich is 8/22 mV positive than that for Pt/C, respectively. Additionally,\nthe catalyst exhibits much greater stability than Pt/C. Kinetics investigations\nshow that the catalyst follows the efficient 4-electron pathway for\nORR in both the alkaline and acidic electrolyte.