Ultralong Layered NaCrO2 Nanowires: A Competitive Wide-Temperature-Operating Cathode for Extraordinary High-Rate Sodium-Ion Batteries

ACS Appl Mater Interfaces. 2019 Jan 30;11(4):4037-4046. doi: 10.1021/acsami.8b20149. Epub 2019 Jan 15.

Abstract

The development of high-rate cathodes particularly with remarkable wide-temperature-tolerance sodium-storage capability plays a significant role in commercial applications of sodium-ion batteries (SIBs). Herein, we devise a scaled-up electrospinning avenue to fabricate nanocrystal-constructed ultralong layered NaCrO2 nanowires (NWs) toward SIBs as a wide-temperature-operating cathode. The resultant one-dimensional (1D) NaCrO2 nanoarchitecture is endowed with orientated and shortened electronic/ionic transport and remarkable structural tolerance to stress change over sodiation-desodiation processes. Benefiting from these structural superiorities, the NaCrO2 NWs are featured with prominent Na+-storage behaviors in the wide-operating-temperature range from -15 to 55 °C. Promisingly, the NaCrO2 NWs exhibit extraordinary high-rate capacities of ∼108.8 and ∼87.2 mAh g-1 at 10 and 50 C rates at 25 °C, and even 94.6 (55 °C) and ∼60.1 (-15 °C) mAh g-1 at 10 C, along with outstanding cyclic stabilities with capacity retentions of ∼80.6% (-15 °C), 88.4% (25 °C), and ∼86.9% (55 °C). The overall performance of our NaCrO2 is superior to other reported NaCrO2-based cathodes, even with conductive nanocarbon coating. Encouragingly, a competitive energy density of ∼161 Wh kg-1 can be obtained by the NaCrO2 NWs-based full cell. Therefore, our NaCrO2 NWs can be highly anticipated as advanced cathode for commercial wide-temperature-tolerance SIBs.

Keywords: NaCrO2; high-rate cathode; sodium-ion batteries; ultralong nanowires; wide-temperature-tolerance.