水热电化学法制备LiCoO_2薄膜和粉末

Fabrication of LiCoO_2 Film and Powder by Hydrothermal-electrochemical Method

采用水热电化学法同时制备出LiCoO2 粉末和薄膜。LiCoO2 粉末是由菊花状晶粒组成 ,LiCoO2 薄膜由0 .2～ 0 .4 μm左右的颗粒堆积而成。LiCoO2 薄膜电极首次循环伏安过程在 3.85V和 4 .3V左右出现强氧化峰 ,在 3.6V左右出现还原峰 ;LiCoO2 粉末的首次循环伏安过程在 4 .3V左右出现强氧化峰 ,在 3.5V左右出现还原峰 ;在随后的循环中 ,氧化和还原峰对应的电位和强度衰减程度小 ,表明该方法制备的LiCoO2 正极材料具有良好的循环伏安性能。

LiCoO 2 powder and film have been directly prepared at the same time by hydrothermal-electrochemical method. The LiCoO 2 powder is an aggregation of some rosette crystal grains, and the LiCoO 2 film consists of grains with a size of 0.2～0.4μm. The LiCoO 2 films present, for the first cycle, well defined anodic peaks, with peak potentials located at 3.85V and 4.3V. Also, a cathodic peak located at 3.6V is observed. The LiCoO 2 powders present, for the first time, well defined anodic/cathodic peaks, with peak potentials located at 4.3V/3.5V. On continuously cycling, the anodic / cathodic peak potentials and intensity tend to attenuate in little range, which indicates that the LiCoO 2 prepared by this method has good cyclability.