Phase separation tendencies of aluminum-doped transition-metal oxides (LiAl(1-x)M(x)O(2)) in the alpha-NaFeO(2) crystal structure
JOURNAL OF THE ELECTROCHEMICAL SOCIETY, vol.146, no.12, pp.4335-4338, 1999 (SCI-Expanded, Scopus)
- Publication Type: Article / Article
- Volume: 146 Issue: 12
- Publication Date: 1999
- Doi Number: 10.1149/1.1392639
- Journal Name: JOURNAL OF THE ELECTROCHEMICAL SOCIETY
- Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
- Page Numbers: pp.4335-4338
- Open Archive Collection: AVESIS Open Access Collection
- Middle East Technical University Affiliated: Yes
Abstract
First-principles methods are used to calculate the miscibility of eight aluminum-doped transition-metal oxides in the layered alpha-NaFeO(2) structure. This study finds that for all Li(Al,M)O(2) compounds investigated(M = Ti, V, Cr, Mn, Fe, Co, Ni, Cu) the enthalpy of mixing is positive. In addition, detailed analyses were performed on LiA(1-x)Co(x)O(2) and LiA(1-x)Cr(x)O(2) by calculating full temperature-composition phase diagrams. For the Li(Al,Co)O(2) system, we find regions of immiscibility below - 173 degrees C and above 600 degrees C. For both Li(Al,Co)O(2) and Li(A1,Cr)O(2) above 600 degrees C, Al-doping is limited by the formation of gamma-LiAlO(2). (C) 1999 The Electrochemical Society. S0013-4651(99)06-122-4. All rights reserved.