Electrochimica Acta, Vol.257, 146-154, 2017
Unravelling the electrochemical properties and thermal behavior of NaNi2/3Sb1/3O2 cathode for sodium-ion batteries by in situ X-ray diffraction investigation
Honeycomb ordered NaNi2/3Sb1/3O2 (NNSO) is synthesized via a conventional solid-state approach and investigated as cathode material for sodium ion batteries. The effect of sintering temperature is clearly unraveled by combination with electrochemical measurements and in-situ XRD tests in detail. The temperature dependence of Na+ (de) intercalation on NaNi2/3Sb1/3O2 electrodes is pioneeringly evaluated. It is suggested that the appropriate operating temperature will facilitate the formation of well-crystallized honeycomb structure and improve the electrochemical performance effectively. The asprepared NaNi2/3Sb1/3O2 obtained at the optimal temperature of 950 degrees C delivers a high capacity of 113.8 mAh g(-1) at 0.1C and a good retention performance of 65 mAh g(-1) at 0.5C after 100 cycles. The results reveal that the structure transformation and electrochemical property, as well as thermal stability of NaNi2/3Sb1/3O2 cathode are strongly dependent on sintering temperatures, which provide an insight into the preparation of newly electrodes with excellent Na+ ion storage property. (C) 2017 Elsevier Ltd. All rights reserved.
Keywords:Sodium ion batteries;Cathode;NaNi2/3Sb1/3O2;Temperature-dependent;In situ X-ray diffraction