Phase evolution and microwave dielectric properties of Li 4 Ti 5(1+x) O 12 ceramics
| Autor: | Jian Zhang, Shishun Qi, Yang Wang, Ruzhong Zuo |
|---|---|
| Rok vydání: | 2016 |
| Předmět: |
Permittivity
Materials science Microwave dielectric properties Analytical chemistry Mineralogy chemistry.chemical_element Sintering 02 engineering and technology Dielectric engineering.material 01 natural sciences Impurity 0103 physical sciences General Materials Science Ceramic 010302 applied physics Mechanical Engineering Spinel 021001 nanoscience & nanotechnology Condensed Matter Physics chemistry Mechanics of Materials visual_art engineering visual_art.visual_art_medium Lithium 0210 nano-technology |
| Zdroj: | Materials Letters. 164:353-355 |
| ISSN: | 0167-577X |
| Popis: | Li 4 Ti 5(1+ x ) O 12 (−0.15≤ x ≤0.10) ceramics were successfully prepared via a conventional solid state method. The phase evolution, sintering behavior and microwave dielectric properties were systematically studied. As x ≥0, TiO 2 appeared as a secondary phase. Single phase Li 4 Ti 5 O 12 was obtained at x =−0.10 to −0.05 with a cubic spinel structure, belonging to Fd−3m space group. Another impurity Li 2 TiO 3 arose at x =−0.15, probably resulting from the overmuch Ti vacancies in the structure. Highest e r (~26) and Q×f (~68000 GHz) were achieved in pure-phase Li 4 Ti 5 O 12 ( x =−0.10), because suitable excess lithium not only compensated for the volatilization of lithium but greatly promoted the sintering behavior. Moreover, with the help of TiO 2 , τ f values of the ceramics within 0≤ x ≤0.10 were adjusted to near zero, accompanied with excellent microwave dielectric properties of e r =18~24, Q×f ~10000 GHz. Furthermore, these samples were chemically compatible with Ag. Thus, the Li 4 Ti 5(1+ x ) O 12 (−0.15≤ x ≤0.10) ceramics could be promising medium permittivity materials in consideration of their low cost, low sintering temperature and superior properties. |
| Databáze: | OpenAIRE |
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