沉积条件对LiCoO_2薄膜结构与形貌的影响

Effect of deposition condition on structure and morphology of pulsed-laser deposited LiCoO_2 films

采用脉冲激光沉积(PLD)方法制备了LiCoO2薄膜,并研究了沉积条件对PLD生长的LiCoO2薄膜结构和形貌的影响。结果表明,适当减少激光功率可以有效降低LiCoO2薄膜表面粗糙度;采用在400℃原位退火可以得到层状结构的LiCoO2薄膜,而在一定范围内提高原位退火温度和升高氧气偏压可以提高层状结构的LiCoO2薄膜的结晶度。本实验中最优工艺制备的LiCoO2薄膜具有较好电化学可逆性,首次放电容量为36μAh/(μm.cm2),循环效率为94.44%。

In this work, pulsed laser deposition （PLD） was used to grow LiCoO2 films and the effect of the deposition conditions, on the structure and morphology of LiCoO2 films was investigated. The results showed that the surface roughness of LiCoO2 films can be reduced by decreasing the laser power to a certain degree and the crystallinity of LiCoO2 films can be improved by elevating the annealing temperature and increasing the oxygen pressure although layered LiCoO2 films can be obtained by in-situ annealing at as low as 400℃. The LiCoO2 films under the optimized deposition condition have good electrochemnical reversibilty with an initial discharge capacity of 36μAh/（μm · cm^2） and a cycling efficiency of 94.44%.