The development of high-efficient and low-cost oxygen reduction reaction (ORR) electrocatalysts is crucial for the practical applications of metal-air batteries. One promising way is to develop Fe single-atom catalysts. However, the single active center and inherent electronic structure of Fe single-atom catalysts lead to the undesirable adsorption of multiple ORR intermediates. Herein, a charge-asymmetry single-atom alloy (SAA) catalyst with Fe–Cu dual sites supported on nitrogen-doped carbon nanosheet (Fe₁Cu SAA/NC) was constructed. Various characterizations manifest the existence of electron interaction between Fe and Cu in Fe₁Cu SAA/NC, which facilitates the adsorption of ORR intermediate for fast kinetics. Consequently, the charge-asymmetry Fe₁Cu SAA/NC exhibits much faster ORR kinetics with a half-wave potential of 0.917 V vs. reversible hydrogen electrode (RHE), outperforming its counterparts in the references. Furthermore, Fe₁Cu SAA/NC still maintains a high half-wave potential with only a drop of 5 mV after 5000 cycles, indicating excellent stability. This work provides a new strategy to design highly active and non-noble metal ORR electrocatalysts, which hold great potential for various catalytic applications.

开发高效、低成本的氧还原反应（ORR）电催化剂对于金属-空气电池的实际应用至关重要。一种有前途的方法是开发铁单原子催化剂。然而，Fe单原子催化剂的单一活性中心和固有的电子结构导致了多个ORR中间体的不良吸附。在此，构建了一种负载在氮掺杂碳纳米片上的具有Fe-Cu双位点的电荷不对称单原子合金（SAA）催化剂（Fe _{1 Cu SAA/NC）。各种表征表明Fe 1} Cu SAA/NC中Fe和Cu之间存在电子相互作用，这有利于ORR中间体的吸附以实现快速动力学。因此，与可逆氢电极 (RHE) 相比，电荷不对称 Fe ₁ Cu SAA/NC 表现出更快的 ORR 动力学，半波电位为 0.917 V，优于参考文献中的同类电极。此外，Fe ₁ Cu SAA/NC在5000次循环后仍保持较高的半波电位，仅下降了5 mV，表现出优异的稳定性。这项工作为设计高活性非贵金属ORR电催化剂提供了一种新策略，该催化剂在各种催化应用中具有巨大潜力。