The development of efficient Oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) bifunctional catalysts from biomass is of significant importance for the commercial application of zinc-air batteries (ZABs). Herein, a bifunctional catalyst (FeCoNi@SNC) is successfully synthesized through introducing Fe, Co and Ni atoms, fish scale-derived carbon (CFS) as the precursor, thiourea and dicyandiamide (DCDA) as the S and N sources, respectively. More importantly, FeCoNi@SNC is identified as a composite material containing FeCo, FeNi3 and metal sulfides. A large number of fluffy carbon nanotubes are induced to grow on the CFS surface by metal nanoparticles, while M-N, M-O and M-S are formed. The catalytic performance is positively influenced by the unique morphology and different active sites of FeCoNi@SNC. To our delight, FeCoNi@SNC exhibits excellent catalytic activity in both ORR (E1/2=0.85 V) and OER (Ej=10= 1.556 V). As a cathode in zinc-air batteries, FeCoNi@SNC possesses significant potential with a peak power density of 146.9 mW cm−2, a specific capacity of 706.9 mAh g−1, and an open circuit voltage of 1.525 V. A novel approach is provided by this work for designing biomass-derived ORR/OER bifunctional catalysts and their application in zinc-air batteries.
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