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Recently,there has been a continuous requirement for high active,excellently durable,and low-cost electrocatalysts for rechargeable zinc air battery.Among many low-cost metal based candidates,transition metal oxides with the CNTS composite have gained increasing attention.In this paper,MnO2 nanotube-supported Co3O4 nanoparticles and its carbon nanotubes hybrid material(Co3O4/MnO2-CNTs)was successfully synthesized by using a co-precipitation method combined with post-heat treatment.The morphology and composition of the catalyst are analyzed through SEM,TEM,TEM-mapping,XRD,EDX and XPS.The hybrid Co3O4/MnO2-CNTs nanomaterials exhibit outstanding catalytic activity toward oxygen reduction reaction and oxygen evolution reaction under alkaline conditions(6M KOH)compared with other catalyst such as the commercial 20%Pt/C,Co3O4/MnO2,sole MnO2 nanotubes and CNTs by LSV.Moreover,primary and rechargeable Zn-air batteries made with the optimal catalyst to prove its prominently bifunctional activity and stability.The hybrid Co3O4/MnO2-CNTs-350 shows a decent open circuit voltage(~1.47V),a high discharge peak power density(340 mW cm-2)and a large specific capacity(775 mAh g-1 at 10 mA cm-2)for primary Zn-air battery.In a rechargeable Zn-air battery,this optimal bifunctional catalyst reveals small charge–discharge voltage gap(<1.1V)and much higher cycle-life(504 cycles at 10 mA cm-2 with 10 min per cycle).More importantly,the simple synthesis method is also suitable for the large-scale production of this bifunctional material owing to simple process and effective cost.