3d(Fe)-5d(W) diatomic hybrid oxygen electrocatalysts enables ultra-stable operation of rechargeable zinc-air batteries for over 10,000 h

Durable and highly active oxygen electrocatalysts are crucial to the large-scale application of rechargeable zinc-air batteries. In this work, we utilized the N ₄ unit in Pc molecule to trap the tungsten atoms scratched off from the tungsten carbide milling balls and placed the obtained W-N ₄ unit close adjacent to the Fe-N ₄ units in FePc, resulting in highly active Fe-N ₄ /W-N ₄ diatomic sites with well-pronounced 3d-5d hybrid for efficient and durable oxygen electrocatalysis. The electron distribution of the Fe-N ₄ site is optimized by the neighboring W-N ₄ site, which facilitates the O ₂ activation and the desorption of *OH and enhances the catalytic activity of the Fe-N ₄ site. Meanwhile, the unsaturated 5d orbitals and tunable valence of the W atoms could modulate the electronic state of the Fe species, prevent leaching, and further enhance the catalytic stability. The resulting zinc-air battery with Fe,W-N-C air cathode exhibited unprecedented cycling stability and repeatability for over 10,000 hours. This remarkable stability improvement not only provides new perspectives for the commercialization of ultra-stable zinc-air batteries but also highlights the critical step in developing 5d metal-boosted 3d metal active sites to fabricate efficient oxygen electrocatalysts.