Growth of HT-LiCoO2 thin films on Pt-metalized silicon substrates  

作　　者：ZHANG Yao CHUNG Chiyuen ZHU Min 

机构地区：[1]School of Mechanical Engineering, South China University of Technology, Guangzhou 510640, China [2]Department of Physics and Materials Science, City University ofHong Kong, Hong Kong, China

出　　处：《Rare Metals》2008年第3期266-272,共7页稀有金属（英文版）

基　　金：This work was financially supported by the CERG(Competitive Earmarked Research Grant)grant from Research Grants Council of the Hong Kong Special Administrative Region,China(CityU 1316/03E);the National Natural Science Foundation of China(No.50401015);the Program of the Ministry of Education of China for Changjiang Scholars and Innovative Research Team in Universities(No.1RT 0551);the Natural Science Foundation of Guang-dong Province,China under the Team Project.

摘　　要：Layered LiCoO2 （HT-LiCoO2） films were grown on Pt-metalized silicon （PMS） substrates and polished bulk nickel （PBN） substrates by pulsed laser deposition. The effects of substrate temperature, oxygen pressure, and substrate surface roughness on the microstructure of LiCoO2 films were investigated. It has been found that a higher substrate temperature and a higher oxygen pressure favor the formation of better crystallized and less lithium-deficient HT-LiCoO2 films. The HT-LiCoO2 film deposited on PBN substrates consists of large randomly orientated equiaxial grains, whereas on PMS substrate, it is made up of loosely packed highly [001] preferential orientated triangular shaped grains with the average grain size less than 100 nm. Electrochemical measurements show that the highly [001] preferentially orientated nanostructured HT-LiCoO2 thin film grown on PMS substrate has good structural stability upon lithium insertion/extraction and can deliver an initial discharge capacity of approximately 45μA·h·cm^-2·μm^-1 with a cycling efficiency of above 99% at the charge/discharge rate of 0.5 C.Layered LiCoO2 （HT-LiCoO2） films were grown on Pt-metalized silicon （PMS） substrates and polished bulk nickel （PBN） substrates by pulsed laser deposition. The effects of substrate temperature, oxygen pressure, and substrate surface roughness on the microstructure of LiCoO2 films were investigated. It has been found that a higher substrate temperature and a higher oxygen pressure favor the formation of better crystallized and less lithium-deficient HT-LiCoO2 films. The HT-LiCoO2 film deposited on PBN substrates consists of large randomly orientated equiaxial grains, whereas on PMS substrate, it is made up of loosely packed highly [001] preferential orientated triangular shaped grains with the average grain size less than 100 nm. Electrochemical measurements show that the highly [001] preferentially orientated nanostructured HT-LiCoO2 thin film grown on PMS substrate has good structural stability upon lithium insertion/extraction and can deliver an initial discharge capacity of approximately 45μA·h·cm^-2·μm^-1 with a cycling efficiency of above 99% at the charge/discharge rate of 0.5 C.

关 键 词：thin film LICOO2 pulsed laser deposition electrochemical properties thin film growth 

分 类 号：O64[理学—物理化学]