The electrochemical oxygen reduction reaction in acidic media offers an attractive route for direct hydrogen peroxide (H₂O₂) generation and on-site applications. Unfortunately there is still a lack of cost-effective electrocatalysts with high catalytic performance. Here, we theoretically designed and experimentally demonstrated that a cobalt single-atom catalyst (Co SAC) anchored in nitrogen-doped graphene, with optimized adsorption energy of the *OOH intermediate, exhibited a high H₂O₂ production rate, which even slightly outperformed the state-of-the-art noble-metal-based electrocatalysts. The kinetic current of H₂O₂ production over Co SAC could reach 1 $\text{mA}/{\text{cm}}_{\text{disk}}^2$ at 0.6 V versus reversible hydrogen electrode in 0.1 M HClO₄ with H₂O₂ faraday efficiency > 90%, and these performance measures could be sustained for 10 h without decay. Further kinetic analysis and operando X-ray absorption study combined with density functional theory (DFT) calculation demonstrated that the nitrogen-coordinated single Co atom was the active site and the reaction was rate-limited by the first electron transfer step.

酸性介质中的电化学氧还原反应为直接产生过氧化氢（H ₂ O ₂）和现场应用提供了一种有吸引力的途径。不幸的是，仍然缺乏具有高催化性能的具有成本效益的电催化剂。在这里，我们从理论上设计和实验证明，锚固在掺氮石墨烯中的钴单原子催化剂（Co SAC）具有优化的* OOH中间体吸附能，具有较高的H ₂ O ₂生成率，甚至略胜一筹。最先进的贵金属基电催化剂。Co SAC上H ₂ O ₂产生的动能可达到1$\text{嘛}/{\text{厘米}}_{\text{磁碟}}^2$相对于可逆的氢电极，在0.1 V HClO _4中使用0.6 V时，H ₂ O ₂法拉第效率> 90％，并且这些性能指标可以维持10 h而不会衰减。进一步的动力学分析和操作X射线吸收研究与密度泛函理论（DFT）的结合表明，氮配位的单个Co原子是活性位点，反应受第一步电子转移步骤的速率限制。