Na2/3MnO2 nanoplates with exposed active planes as superior electrochemical performance sodium-ion batteries

Sodium-ion batteries (SIBs) with huge cost advantages will show extraordinary talents in low-speed electric vehicles, energy storage, and base station communications. Manganese oxides are promising candidates for cathode materials, rapid capacity decay, and poor electrochemical performance that limit its commercial applications. Here, the nanosheets with exposed active crystal planes are prepared through a simple NH3∙H2O-assisted sol-gel process and subsequent high-temperature calcination. The unique structure considerably reduces the Na+ diffusion path for the excellent Na+ diffusion kinetics. The final results confirm that the NMO-pH6 sample, exposed to the active planes, has high energy density (557.9 Wh kg−1 at 0.1 C) and outstanding electrochemical performance, especially the rate performance (93.8 mAh g−1 at 5 C and 79.95 %, 100 cycles at 1 C). More importantly, it will facilitate the further construction of advanced cathode materials for high-performance SIBs.