γ-Li4-3xAlxGeO4 solid electrolytes: Phase equilibria, conductivity and glass-transition-like behaviour
The phase diagram Li4GeO4-LiAlGeO4 has been shown to contain a short range of Li4GeO4 solid solutions, a range of γ solid solutions, Li4-3xAlxGeO4 [where (0.04-0.13) < x < 0.30] and a line phase, α, with x = 0.375. The γ solid solutions are stable up to melting at 1140-1160°C and the α phase i...
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| Format: | Article |
| Language: | English |
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Royal Society of Chemistry (RSC)
1993
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| Online Access: | http://psasir.upm.edu.my/id/eprint/115243/ http://psasir.upm.edu.my/id/eprint/115243/1/115243.pdf |
| _version_ | 1848866724414226432 |
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| author | Lee, Chnoong Kheng West, Anthony R. |
| author_facet | Lee, Chnoong Kheng West, Anthony R. |
| author_sort | Lee, Chnoong Kheng |
| building | UPM Institutional Repository |
| collection | Online Access |
| description | The phase diagram Li4GeO4-LiAlGeO4 has been shown to contain a short range of Li4GeO4 solid solutions, a range of γ solid solutions, Li4-3xAlxGeO4 [where (0.04-0.13) < x < 0.30] and a line phase, α, with x = 0.375. The γ solid solutions are stable up to melting at 1140-1160°C and the α phase is stable between 1080 and 1160°C only. X-Ray powder data are given for α and γ solid solutions. The γ solid solutions exhibit a remarkable temperature-independent conductivity of Li+ ions above ca. 700°C which is particularly noticeable at low values of x. With decreasing temperature, Li+ ion motion is increasingly thermally activated, with an activation energy of 0.45-0.60 eV at temperatures below 300°C. The highest room-temperature conductivity was ca. 2 x 10-5 Ω-1 cm-1 in freshly quenched γ samples of x = 0.10, but the conductivity gradually decreased with time owing to ageing. There is evidence from differential scanning calorimetry (DSC) studies of a sluggish order-disorder transition at 200-250°C involving the Li+ ion site occupancies, which has many of the characteristics of a glass transition. An additional second-order transition occurs at 480-500°C which is attributed to a change from disordered to liquid-like properties of the mobile Li+ ions. |
| first_indexed | 2025-11-15T14:25:09Z |
| format | Article |
| id | upm-115243 |
| institution | Universiti Putra Malaysia |
| institution_category | Local University |
| language | English |
| last_indexed | 2025-11-15T14:25:09Z |
| publishDate | 1993 |
| publisher | Royal Society of Chemistry (RSC) |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | upm-1152432025-02-26T08:39:02Z http://psasir.upm.edu.my/id/eprint/115243/ γ-Li4-3xAlxGeO4 solid electrolytes: Phase equilibria, conductivity and glass-transition-like behaviour Lee, Chnoong Kheng West, Anthony R. The phase diagram Li4GeO4-LiAlGeO4 has been shown to contain a short range of Li4GeO4 solid solutions, a range of γ solid solutions, Li4-3xAlxGeO4 [where (0.04-0.13) < x < 0.30] and a line phase, α, with x = 0.375. The γ solid solutions are stable up to melting at 1140-1160°C and the α phase is stable between 1080 and 1160°C only. X-Ray powder data are given for α and γ solid solutions. The γ solid solutions exhibit a remarkable temperature-independent conductivity of Li+ ions above ca. 700°C which is particularly noticeable at low values of x. With decreasing temperature, Li+ ion motion is increasingly thermally activated, with an activation energy of 0.45-0.60 eV at temperatures below 300°C. The highest room-temperature conductivity was ca. 2 x 10-5 Ω-1 cm-1 in freshly quenched γ samples of x = 0.10, but the conductivity gradually decreased with time owing to ageing. There is evidence from differential scanning calorimetry (DSC) studies of a sluggish order-disorder transition at 200-250°C involving the Li+ ion site occupancies, which has many of the characteristics of a glass transition. An additional second-order transition occurs at 480-500°C which is attributed to a change from disordered to liquid-like properties of the mobile Li+ ions. Royal Society of Chemistry (RSC) 1993 Article PeerReviewed text en http://psasir.upm.edu.my/id/eprint/115243/1/115243.pdf Lee, Chnoong Kheng and West, Anthony R. (1993) γ-Li4-3xAlxGeO4 solid electrolytes: Phase equilibria, conductivity and glass-transition-like behaviour. J. Mater. Chem., 3 (2). pp. 191-196. ISSN 0959-9428; eISSN: 1364-5501 https://pubs.rsc.org/en/content/articlelanding/1993/jm/jm9930300191 10.1039/JM9930300191 |
| spellingShingle | Lee, Chnoong Kheng West, Anthony R. γ-Li4-3xAlxGeO4 solid electrolytes: Phase equilibria, conductivity and glass-transition-like behaviour |
| title | γ-Li4-3xAlxGeO4 solid electrolytes: Phase equilibria, conductivity and glass-transition-like behaviour |
| title_full | γ-Li4-3xAlxGeO4 solid electrolytes: Phase equilibria, conductivity and glass-transition-like behaviour |
| title_fullStr | γ-Li4-3xAlxGeO4 solid electrolytes: Phase equilibria, conductivity and glass-transition-like behaviour |
| title_full_unstemmed | γ-Li4-3xAlxGeO4 solid electrolytes: Phase equilibria, conductivity and glass-transition-like behaviour |
| title_short | γ-Li4-3xAlxGeO4 solid electrolytes: Phase equilibria, conductivity and glass-transition-like behaviour |
| title_sort | γ-li4-3xalxgeo4 solid electrolytes: phase equilibria, conductivity and glass-transition-like behaviour |
| url | http://psasir.upm.edu.my/id/eprint/115243/ http://psasir.upm.edu.my/id/eprint/115243/ http://psasir.upm.edu.my/id/eprint/115243/ http://psasir.upm.edu.my/id/eprint/115243/1/115243.pdf |