Air-based flow batteries have triggered huge interests as promising large-scale energy storage devices due to their high energy density and extremely low cost. However, the sluggish kinetics of oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) lower their energy conversion efficiencies. Herein, we in situ grow amorphous NiS_x-FeO_y particles on sulfur doped carbon fiber paper (termed as NiS_x-FeO_y/SCFP) as practical self-supported oxygen electrode through a simple and economic synthesis route. Benefiting from the synergetic effects of amorphous NiS_x-FeO_y and SCFP, NiS_x-FeO_y/SCFP possesses massively accessible active sites, enhanced electrons and reactants transfer, and stable integrated structure, exhibiting a low overpotential (0.37 V) at 10 mA cm⁻² for OER, a positive half-wave potential for ORR and a small potential gap (0.82 V). Zinc air flow battery assembled with newly developed NiS_x-FeO_y/SCFP shows a coulombic efficiency of 100% and a voltage efficiency of 50% at the charge-discharge current of 10 mA cm⁻², and vigorously operates 110 h without performance decay, showing highly catalytic activity and super cycling stability, which are among the best performance ever reported. We believe that this work will open up new ways for fabricating practical oxygen electrode for metal air based batteries applications.

空气液流电池由于其高能量密度和极低的成本而引起了人们的广泛兴趣，成为有前途的大型储能设备。但是，氧还原反应（ORR）和氧释放反应（OER）的动力学缓慢，降低了它们的能量转换效率。本文中，我们通过一种简单而经济的合成路线，在掺硫碳纤维纸上原位生长非晶态NiS _x -FeO _y颗粒（称为NiS _x -FeO _y / SCFP）作为实用的自支撑氧电极。受益于非晶态NiS _x -FeO _y和SCFP的协同作用，NiS _x -FeO _y/ SCFP具有可大量访问的活性位点，增强的电子和反应物转移以及稳定的集成结构，对于OER在10 mA cm ^-2处显示出低的过电势（0.37 V），对于ORR来说是正半波电势，并且电势隙小（ 0.82 V）。使用新开发的NiS _x -FeO _y / SCFP组装的锌空气流通电池在10 mA cm ^-2的充放电电流下具有100％的库仑效率和50％的电压效率。，并在不影响性能的情况下剧烈运转110小时，显示出高催化活性和超级循环稳定性，这是有史以来最好的性能之一。我们相信这项工作将为金属空气电池应用中的实际氧电极的开发开辟新的途径。