Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
9803967 | Journal of Alloys and Compounds | 2005 | 9 Pages |
Abstract
The addition of aliovalent element plays an important role on the structural, electrical and electrochemical properties of LaMnO3. In this study, 10% of Li was incorporated into the A-site of the LaMnO3 perovskite. The addition of more than 10% Li resulted in the formation of the LiMn2O4 spinel as a second phase. The conductivity of LaMnO3 was also effectively enhanced by the addition of Li. The undoped LaMnO3 exhibits a conductivity of 0.25 Ωâ1 cmâ1 at 27 °C. In the LaMnO3 sample doped with 10% Li, the conductivity increased to 2.25 Ωâ1 cmâ1 at 27 °C. For 30% Li-doped LaMnO3, the lower conductivity of 1.31 Ωâ1 cmâ1 at 27 °C was observed due to the formation of poor-conducting LiMn2O4. In all the samples doped with Li, the activation energy (17.20-18.17 kJ/mol) for electrical conduction was much lower than that of undoped LaMnO3 (26.71 kJ/mol). The reduction in activation energy can be rationalized by the creation of electron holes due to the addition of Li. In the sample with the composition of La0.9Li0.1MnO3, the cyclic voltammetry and charge/discharge tests indicated that the sample was not electrochemically active.
Related Topics
Physical Sciences and Engineering
Materials Science
Metals and Alloys
Authors
Fu-Yun Shih, Kuan-Zong Fung,