Moon Sang-Hyun, Kim Min-Cheol, Kim Eun-Soo, Shin Yeon-Kyung, Lee Ji-Eun, Choi Sojeong, Park Kyung-Won
Department of Chemical Engineering, Soongsil University Seoul 06978 Republic of Korea
RSC Adv. 2019 Mar 11;9(14):7903-7907. doi: 10.1039/c8ra10451d. eCollection 2019 Mar 6.
We fabricated lithium cobalt oxide (LiCoO, LCO) electrodes in the absence and presence of TiO layers as cathodes for lithium-ion batteries (LIBs) using a sputtering deposition method under an Ar atmosphere. In particular, TiO coating layers on sputtered LCO electrodes were directly deposited in a layer-by-layer form with varying TiO sputtering times from 60 to 120 s. These sputtered electrodes were heated at 600 °C in an air atmosphere for 3 h. The thicknesses of TiO layers in TiO-coated LCO electrodes were controlled from ∼2 to ∼10 nm. These TiO-coated LCO electrodes exhibited superior electrochemical performance, high capacities (93-107 mA h g@0.5C), improved retention of >60% after 100 cycles, and high-rate cycling properties (64 mA h g@1C after 100 cycles). Such an improved performance of TiO-coated LCO electrodes was found to be attributed to relieved volumetric expansion of LCO and protection of LCO electrodes against HF generated during cycling.
我们在氩气气氛下，采用溅射沉积法，在有无TiO层的情况下制备了钴酸锂（LiCoO，LCO）电极作为锂离子电池（LIBs）的阴极。特别地，溅射LCO电极上的TiO涂层以逐层形式直接沉积，TiO溅射时间从60秒到120秒不等。这些溅射电极在空气气氛中于600°C加热3小时。TiO包覆LCO电极中TiO层的厚度控制在约2至约10纳米。这些TiO包覆的LCO电极表现出优异的电化学性能、高容量（在0.5C下为93 - 107 mA h g）、100次循环后保留率提高>60%以及高倍率循环性能（100次循环后在1C下为64 mA h g）。发现这种TiO包覆LCO电极性能的改善归因于LCO体积膨胀的缓解以及LCO电极在循环过程中免受HF的侵蚀。
