Ordered Adsorption of Oxygen via High-Density Low-Coordinated\nRu Sites for Lithium–Oxygen Battery

Lithium–oxygen\nbatteries (LOBs), despite high-energy densities,\ngenerally suffer from poor cycling performances, which put severe\nconstraints on their commercialization. Herein, we demonstrate a cathode\ncatalyst featuring a hollow structure with high-density, low-coordinated\nRu active sites. The high-density low-coordinated Ru active sites\ncould efficiently activate oxygen via bridge-adsorption configuration,\nand the hollow architecture could optimize the access of oxygen to\nthe active sites and accommodate more Li<sub>2</sub>O<sub>2</sub>.\nThese structural features could direct the Li<sub>2</sub>O<sub>2</sub> to grow along the (010) faces into a unique highly dispersed fluff-like\nmorphology, which could be readily decomposed in charge process, thereby\nconferring a long battery stability under high-rate current, the LOB\ncapable of running stably for >700 cycles under the high-rate current\ndensity of 1 A·g<sup>–1</sup>.