Nitrogen‐Doped Bimetallic Carbide‐Graphite Composite as Highly Active and Extremely Stable Electrocatalyst for Oxygen Reduction Reaction in Alkaline Media

Abstract It is demonstrated that nitrogen‐doped bimetallic carbide‐graphite composite (N‐Fe₂MoC‐GC) has much superior oxygen reduction reaction (ORR) activity to commercial Pt/C with ultrahigh stability, and excellent anti‐methanol and anti‐CO performances. The N‐Fe₂MoC‐GC has a high initial half‐wave potential of 0.887 V (versus RHE); its mass activity (83 mA mg_cat.⁻¹ at 0.9 V versus RHE) is 2.2 times that of Pt/C (40 wt%, 39 mA mg_cat.⁻¹). In H₂/O₂ alkaline fuel cell, the N‐Fe₂MoC‐GC keeps 92.9% of the initial power density (1.12 W cm⁻²) within 70 000 cycles, ranking it as one of the most active and stable noble metal‐free catalysts reported to date. Moreover, the N‐Fe₂MoC‐GC keeps high power density even under low relative humidity or at high operation temperature. The positive charge on Fe and Mo atoms caused by electron transfer from Fe₂MoC to N is believed to lead to the excellent ORR activity. The inherent electrochemical stability of the Fe₂MoC and graphite matrix, as well as the strong interaction between components of catalyst caused by electron transfer, accounts for the ultrahigh stability.