Tuning the Reversibility of Oxygen Redox in Lithium-Rich Layered Oxides

Recently, more and more new high-capacity lithium-rich layered oxides involving both metal and oxygen redox have been proposed. However, the structural stability was influenced by the irreversible oxygen redox, which leads to the instability of the oxygen framework. Here, we propose that the reversibility of the oxygen redox in Li2RuO3 can be controlled by tuning its electronic structure via incorporating boron atoms into the interstitial sites of the Li2RuO3 layered structure and obtain higher-stability lithium-rich layered oxides. Using in situ X-ray diffraction and X-ray absorption fine structure, we conclude that oxygen redox was tuned to a reversible level without reduction of Ru as reported previously. The intrinsic mechanism of the modification was further determined by density functional theory calculations. This work will provide a new scope for the strategy of balancing the high capacity and good structural stability of lithium-rich layered oxides.