Layered P2-Na0.7MnO2.05 microflakes as a cathode material for high performance sodium-ion batteries

Sodium-ion batteries(SIBs),as the low-cost and large-scale energy storage devices,have attracted wide attention,but their capacity and cycle performance are limited by cathode materials.Here,P2-Na0.7MnO2.05microflakes with the diameter 500 nm to 1μm are synthesized by an improved solid-state reaction.The as-prepared P2-Na0.7MnO2.05microflakes exhibit excellent electrochemical performance when tested as a cathode material of SIBs.It delivers a considerably reversible capacity of 142.7 mA h g-1at a current density of 0.3C(1C=180 mA g-1)with a slow capacity decay to121.5 mA h g-1after 50 cycles.Even at a high current density of 2C,the P2-Na0.7MnO2.05microflakes still show a specific capacity of 88.9 mA h g-1with a capacity retention of 75%after 100 cycles.The above performance of Na0.7MnO2.05microflakes are better than Na0.7MnO2.05with large block morphology,which is mainly attributed to the lamellar morphology of P2-Na0.7MnO2.05alleviating structural deformation and accelerating reaction kinetics.This strategy will provide new opportunities to develop stable oxide cathodes for SIBs.