It is tremendously desired to fabricate high-performance, low-cost and highly capable electrocatalysts performing oxygen electrocatalytic reactions (reduction and evolution) in rechargeable metal–air batteries. In this study, heterostructure of NiCoFe-layerd double hydroxide (LDH)/ Ti₃C₂ (MXene)/N-doped carbon nanotube (NCNT) was constructed via a simple hydrothermal method. Thanks to the hybrid porous architecture possessing extensive surface area, high electrical conductivity, plentiful active sites, optimum nitrogen content and robust electronic interactions in the NiCoFe-LDH/ Ti₃C₂ MXene/ NCNT, the resulted composite presented superb electrocatalytic activity toward oxygen evolution reaction (OER) and oxygen reduction reaction (ORR). Specially, it showed an overpotential of 332 mV to reach J=10 mA cm^-2 for the OER and at the same time presented starting potential of E_onset= 0.93 V_RHE with E_1/2=0.78 V_RHE for the ORR. In addition, utilized in a Zn-air battery, it exhibited higher power density and greater cycling capability than Pt/C-IrO₂ catalyst, introducing it as a promising catalyst for rechargeable Zn-air batteries.

非常需要制造高性能、低成本和高性能的电催化剂，在可充电金属-空气电池中进行氧电催化反应（还原和放出）。在这项研究中，NiCoFe 层状双氢氧化物 (LDH)/Ti ₃ C ₂ (MXene)/N 掺杂碳纳米管 (NCNT) 的异质结构是通过简单的水热方法构建的。由于混合多孔结构在 NiCoFe-LDH/Ti ₃ C _{2 中}具有广泛的表面积、高导电性、丰富的活性位点、最佳的氮含量和强大的电子相互作用MXene/ NCNT，所得复合材料对析氧反应（OER）和氧还原反应（ORR）表现出极好的电催化活性。特别是，它显示出 332 mV 的过电位，达到OER 的J=10 mA cm ^-2，同时呈现出 E _onset = 0.93 V _{RHE 的}起始电位，ORR 的E _1/2 =0.78 V _RHE。此外，在锌空气电池中，它表现出比 Pt/C-IrO ₂催化剂更高的功率密度和更大的循环能力，使其成为可充电锌空气电池的有前途的催化剂。