Elucidating how the local strain environment of single atoms affects their impact on a sluggish acidic oxygen reduction reaction (ORR) is important for the design and construction of highly active electrocatalysts. Here, we report that the atomic strain geometry of Fe single sites is exclusively regulated by the communicative effects of dual atoms. Theoretical analysis reveals that Fe-Ru dual atoms in a moderate strain environment achieve the lowest Gibbs free energy barrier during an ORR. Impressively, FeRu-N-C with an FeRuN₈ moiety exhibits the highest acidic ORR performance, with a half-wave potential (E_1/2) of 0.860 V and only a 17-mV loss in E_1/2 after 50,000 potential cycles. Operando characterization and electronic configuration analysis demonstrate that moderately strained Fe sites promote hydrogenation desorption of (oxy-)hydroxyl by enabling more electrons to occupy antibonding orbitals. This study describes a promising way of investigating high-performance single-atom-based catalysts by tailoring the atomic strain environment.

阐明单原子的局部应变环境如何影响其对缓慢的酸性氧还原反应（ORR）的影响对于高活性电催化剂的设计和构建非常重要。在这里，我们报告了 Fe 单位点的原子应变几何形状完全由双原子的通信效应调节。理论分析表明，中等应变环境中的 Fe-Ru 双原子在 ORR 过程中实现了最低的吉布斯自由能垒。令人印象深刻的是，具有 FeRuN _8部分的 FeRu-NC表现出最高的酸性 ORR 性能，半波电位 ( E _1/2 ) 为 0.860 V，并且在 50,000 次电位循环后E _1/2仅损失 17 mV 。原位表征和电子构型分析表明，中等应变的 Fe 位点通过使更多电子占据反键轨道来促进（氧）羟基的氢化解吸。这项研究描述了一种通过定制原子应变环境来研究高性能单原子催化剂的有前途的方法。