Ternary metal catalysts hold great promise in complementary functionality and synergistic interplay, which are promising for combined reactions involving multi-intermediates. However, simultaneously downscaling all three metal species into single-atom level still remains challenge. Herein, a universal metal encapsulation-segregation-overlay strategy is designed to realize the fabrication of heterogeneous M¹N₄-C-M²N₄-C-M³N₄ ternary single-atoms (TSAs)-based catalysts, with well-defined configuration and threefold enhancement of single-atom loading (IrPtCu TSAs, up to 21.24 wt%). Taking non-precious-metallic CoN₄-C-NiN₄-C-FeN₄ TSAs for instance, the integration of triple-decker single-atoms affords strong electronic reciprocity, with interbedded Ni donating electrons for both Fe and Co, thereby simultaneously enhancing the catalytic activity for oxygen reduction, oxygen evolution, and hydrogen evolution through a “site-selective master-servant” mechanism. Thanks to the mutually assisted tri-functionality, the CoN₄-C-NiN₄-C-FeN₄ TSAs-electrode takes on alternatating master/servant roles to enable outstanding recyclability for energy devices. This work breaks the obstructions in synthesis and fundamental study of TSAs, providing insights into atomic material design for complicated catalytic reactions.

中文翻译：

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异质 M1N4-C-M2N4-C-M3N4 单原子位点的三元协同作用调控锌空气电池和水分解的电催化途径

三元金属催化剂在互补功能和协同相互作用方面具有广阔前景，这有望用于涉及多中间体的联合反应。然而，同时将所有三种金属物种缩小到单原子水平仍然是一个挑战。在此，设计了一种通用的金属封装-分离-叠加策略，以实现多相 M ¹ N ₄ -CM ² N ₄ -CM ³ N ₄三元单原子 (TSA) 基催化剂的制备，具有明确的配置和单原子负载的三倍增强（IrPtCu TSA，高达 21.24 wt%）。以非贵金属CoN ₄ -C -NiN ₄ -C-FeN₄ TSAs 例如，三层单原子的集成提供了强大的电子互易性，夹层的 Ni 为 Fe 和 Co 提供电子，从而通过“位点”同时增强氧还原、析氧和析氢的催化活性-选择性主仆”机制。由于相互辅助的三功能，CoN 4 -C-NiN _{4 -C} -FeN ₄ TSAs 电极承担交替的主/从角色，使能源设备具有出色的可回收性。这项工作打破了 TSA 合成和基础研究的障碍，为复杂催化反应的原子材料设计提供了见解。