A graphene-like nanoribbon for efficient bifunctional electrocatalysts

Graphene nanoribbons (GNRs) are conducive to full exposure of catalyst sites, which can be used to synthesize highly efficient electrocatalysts. However, the design of stable and efficient GNRs catalysts remains a great challenge. Herein, a novel iron and cobalt co-doped carbon-based catalysts (C-MP-FeCo) with GNRs structure has been developed by a facile and one-step heat-treatment method. C-MP-FeCo is an excellent bifunctional electrocatalysis for low potential difference ΔE between oxygen-evolution reaction and oxygen-reduction reaction (ΔEC-MP-FeCo=0.70 V vs. ΔE(Pt/C+RuO2) =0.765 V). The maximum power reached 331 mW cm-2 at 0.97 V for the Zn-air battery derived from C-MP-FeCo catalyst, and the Pt/C+RuO2 catalyst only 249 mW cm-2 vs. 0.89 V; and also, better discharge performance, voltage efficiency and durability are delivered by the former catalyst. Our findings show that the main methods of increasing electrocatalytic activity are (1) forming GNRs and exposing active sites, (2) synergistic effects of Fe, Co, N, and F.