Integration of CoFe Alloys and Fe/Fe3C Nanoparticles into N-Doped Carbon Nanosheets as Dual Catalytic Active Sites To Promote the Oxygen Electrocatalysis of Zn-Air Batteries

The development of efficient and durable bifunctional electrocatalysts of air electrodes is very important for the commercial application of metal-air batteries. Herein, this work demonstrates the integration of CoFe alloys and Fe/Fe3C nanoparticles into N-doped carbon nanosheets as an effective bifunctional electrocatalyst in Zn-air batteries. Thanks to the independent active sites for oxygen evolution and reduction reaction, the fabricated aqueous Zn-air battery exhibits a desirable operation stability of up to 350 h without significant performance deterioration. The promising power density (154.1 mW.cm(-2)) and specific capacity (803 mA h/g(Zn)) make this hybrid catalyst an ideal substitute for precious metal catalysts. Moreover, the solid-state flexible Zn-air battery has a large power density of 108.4 mW.cm(-2), which is enough to drive 35 diode lights. It is believed that this novel bifunctional catalyst may provide an interesting insight into the design of durable oxygen electrocatalysts for metal-air batteries.