▎ 摘　　要

Highly efficient and low-cost nanomaterials with multifunctions for oxygen evolution reaction (OER), hydrogen evolution reaction (OER) and oxygen reduction reaction (ORR) have been attracted tremendous attentions that play significant roles in energy storage and conversion. Herein, a facile strategy is developed to synthesize metal alloys (NiCo, CoFe) with their oxides supported on nitrogen-doped graphene (N-rGO/NiCo-Nio-CoO, N-rGO/CoFe-Co2FeO4). The obtained nanomaterials exhibit outstanding tri-functional performances for the above mentioned three kinds of reactions. Furthermore, the prepared composites, assembled in air cathodes, present excellent performance that are similar with Pt/C or Pt/C + IrO2 in primary and rechargeable zinc-air batteries. The prepared N-rGO/NiCo-NiO-CoO and N-rGO/CoFe-Co2FeO4 exhibit the specific capacities of 734 and 711 mA h g(Zn)(-1) at the current density of 20 mA cm(-2), respectively. The rechargeable zinc-air batteries maintain excellent durability after cycling 33 h. (C) 2018 Elsevier Ltd. All rights reserved.