Developing efficient and stable non-noble metal oxygen evolution reaction (OER) electrocatalysts for sustainable overall water-splitting is extremely desirable but still a great challenge. Herein, we developed a facile strategy to fabricate Co₃O₄–CoOOH heterostructure nanosheet arrays with oxygen vacancies grown on carbon paper (Co₃O₄–CoOOH/CP). Benefiting from the unique 3D architecture, large surface area, synergistic effects between Co₃O₄, CoOOH and oxygen vacancies, the obtained self-supporting Co₃O₄–CoOOH/CP presents excellent electrocatalytic OER activity (low overpotentials of 245 and 390 mV at 10 and 100 mA cm⁻²) and robust long-term stability in alkaline condition. The present strategy provides the opportunities for the future rational design and discovery of high-performance non-noble metal based electrocatalysts for advanced water oxidation and beyond.

开发高效稳定的非贵金属析氧反应（OER）电催化剂以实现可持续的整体水分解是非常理想的，但仍然是一个巨大的挑战。在此，我们开发了一种简便的策略来制造具有在碳纸上生长的氧空位的Co ₃ O ₄ –CoOOH 异质结构纳米片阵列（Co ₃ O ₄ –CoOOH/CP）。受益于独特的 3D 结构、大表面积、Co ₃ O ₄、CoOOH 和氧空位之间的协同效应，所获得的自支撑 Co ₃ O ₄ –CoOOH/CP 表现出优异的电催化 OER 活性（245 和 390 mV 的低过电位）在 10 和 100 mA cm⁻² ) 和在碱性条件下的长期稳定性。目前的策略为未来合理设计和发现用于高级水氧化及其他方面的高性能非贵金属基电催化剂提供了机会。