Facile synthesis of high performance non-noble-metal electrocatalyst Fe–N–S/C for oxygen reduction reaction in acidic solutions

The development of non-noble metal catalysts is of great interest due to their significant potential application in both fuel cell system and metal-air batteries, particularly when considering long term commercial deployment. Fe/N/C is a promising non-Pt electrocatalyst for the oxygen reduction reaction (ORR), but its catalytic activity is considerably inferior to that of Pt in acidic medium. In this paper, an improved Fe/N/S/C catalyst (denoted as Fe–N–S/C) is presented. Nitrogen-sulfur-iron-doped porous carbon material is synthesized by the pyrolysis of dicyandiamide, a kind of abundant and inexpensive compound, with thiourea as additional sulfur source in argon atmosphere. The Fe–N–S/C shows excellent performance for the ORR with the onset and half-wave potential at 0.89 and 0.78 V (vs.RHE) in 0.1 M H 2 SO 4 solution, respectively, which are significantly higher compared to those of the catalysts derived from only dicyandiamide (0.85 and 0.75 V). Our results indicate that as compared to the commercial 20 % Pt/C catalyst, the synthesized catalyst exhibits not only higher current density and long-term durability but also higher tolerance to methanol poisoning. More importantly, the synthetic method is simple and inexpensive.