Constructing heterostructures to increase the conductivity and enhance reaction kinetics of Co-based oxides is a fascinating yet challenging method for creating effective catalysts for oxygen evolution reaction. The controlled synthesis of multi-phase heterostructures comprising identical elements has been rarely reported in the literature. Herein, a simple and scalable strategy is proposed to prepare a multi-phase heterostructure of Co₃O₄ and CoO through an efficient hydrogen reduction assisted strategy and subsequent surface phosphating treatment. In the process of effectively doping phosphorus (P) atoms, spinel-type Co₃O₄ and rock-salt type CoO heterojunctions are cleverly formed, and an abundance of oxygen defects are also introduced. The spontaneous integration of multi-phase heterostructure of well-crystallized Co elements as well as the incorporation of P on catalyst surface, not only alters the electronic structure to foster the activation of oxygen and the disaggregation of water, but also causes a synergistic effect at the interface. Benefiting from these characteristics, the hybrid catalyst surpasses the RuO₂ benchmark with outstanding OER performance, reaching 10 mA cm⁻² at only 299 mV overpotential and excellent stability in alkaline electrolyte.

构建异质结构以提高钴基氧化物的电导率并增强反应动力学，对于制造析氧反应的有效催化剂来说是一种令人着迷但具有挑战性的方法。文献中很少报道包含相同元素的多相异质结构的受控合成。在此，提出了一种简单且可扩展的策略，通过有效的氢还原辅助策略和随后的表面磷化处理来制备Co ₃ O ₄和CoO的多相异质结构。在有效掺杂磷（P）原子的过程中，巧妙地形成了尖晶石型Co ₃ O ₄和岩盐型CoO异质结，同时引入了大量的氧缺陷。结晶良好的Co元素多相异质结构的自发整合以及P在催化剂表面的结合，不仅改变了电子结构以促进氧的活化和水的解聚，而且在催化剂表面产生协同效应。界面。受益于这些特性，该混合催化剂超越了RuO ₂基准，具有出色的OER性能，在仅299 mV的过电势下达到10 mA cm ^{-2 ，并且在碱性电解质中具有出色的稳定性。}