https://scholars.lib.ntu.edu.tw/handle/123456789/407466
標題: | Influence of the emulsification conditions on the microstructures and electrochemical characteristics of spinel lithium manganese oxide powders | 作者: | Lu C.-H. Lin Y. |
公開日期: | 2003 | 卷: | 18 | 期: | 3 | 起(迄)頁: | 552-559 | 來源出版物: | Journal of Materials Research | 摘要: | Lithium manganese oxide powders (LiMn 2 O 4 ) with a spinel structure were synthesized via an optimized water-in-oil emulsion process. The influence of the emulsification conditions on the microstructures and physicochemical properties of LiMn 2 O 4 powders was investigated. The phase purity of the synthesized powders significantly depends on the water-to-oil volume ratio in the emulsion. Increasing the water-to-oil ratio tends to decrease the stability of the emulsion that in turn leads to a segregation of water and oil phases. The unstable emulsion system results in the formation of an impure phase-Li 2 MnO 3 -that markedly decreases the charge and discharge capacities of the cathode materials. When water/oil volume ratio equals 1/5 or 1/10, monophasic spinel powders are formed at temperatures as low as 400 ¢XC. In addition, decreasing the concentration of the aqueous phase substantially reduces the particle size of LiMn 2 O 4 powders. Nanometered-LiMn 2 O 4 powders with a particle size of 50 nm are obtained when the concentration of the aqueous phase is 1.0 M and the water-to-oil volume ratio is 1/5. Decreasing the particle size of LiMn 2 O 4 powders was demonstrated to effectively increase the specific capacity and improve the cyclability of LiMn 2 O 4 powders. |
URI: | https://scholars.lib.ntu.edu.tw/handle/123456789/407466 | ISSN: | 08842914 | DOI: | 10.1557/JMR.2003.0071 |
顯示於: | 化學工程學系 |
在 IR 系統中的文件,除了特別指名其著作權條款之外,均受到著作權保護,並且保留所有的權利。