Oxygen reduction and evolution reactions are two key processes in electrochemical energy conversion technologies. Synthesis of nonprecious metal, carbon-based electrocatalysts with high oxygen bifunctional activity and stability is a crucial, yet challenging step to achieving electrochemical energy conversion. Here, an approach to address this issue: synthesis of an atomically dispersed Fe electrocatalyst (Fe₁/NCP) over a porous, defect-containing nitrogen-doped carbon support, is described. Through incorporation of a phosphorus atom into the second coordination sphere of iron, the activity and durability boundaries of this catalyst are pushed to an unprecedented level in alkaline environments, such as those found in a zinc-air battery. The rationale is to delicately incorporate P heteroatoms and defects close to the central metal sites (FeN₄P₁-OH) in order to break the local symmetry of the electronic distribution. This enables suitable binding strength with oxygenated intermediates. In situ characterizations and theoretical studies demonstrate that these synergetic interactions are responsible for high bifunctional activity and stability. These intrinsic advantages of Fe₁/NCP enable a potential gap of a mere 0.65 V and a high power density of 263.8 mW cm⁻² when incorporated into a zinc-air battery. These findings underscore the importance of design principles to access high-performance electrocatalysts for green energy technologies.

中文翻译：

---

通过二次配位球工程操纵 Fe 单原子催化剂的电子性质，在锌空气电池中提供增强的氧电催化活性


氧还原和析出反应是电化学能量转换技术中的两个关键过程。合成具有高氧双功能活性和稳定性的非贵金属碳基电催化剂是实现电化学能量转换的关键但具有挑战性的步骤。在这里，描述了一种解决这个问题的方法：在多孔、含缺陷的含氮掺杂碳载体上合成原子分散的 Fe 电催化剂 （Fe₁/NCP）。通过将磷原子掺入铁的第二个配位球中，这种催化剂的活性和耐久性边界在碱性环境中被推到前所未有的水平，例如锌空气电池中的环境。其基本原理是将 P 杂原子和缺陷巧妙地掺入靠近中心金属位点 （FeN₄P_1-OH） 的位置，以打破电子分布的局部对称性。这使得与含氧中间体的结合强度合适。原位表征和理论研究表明，这些协同相互作用是高双功能活性和稳定性的原因。Fe₁/NCP 的这些固有优势在集成到锌空气电池中时，可实现仅 0.65 V 的电位间隙和 263.8 mW ^cm-2 的高功率密度。这些发现强调了设计原则对于获得用于绿色能源技术的高性能电催化剂的重要性。