Synthesis, Crystal Structure, and Stability of Cubic Li7–xLa3Zr2–xBixO12
| Autor: | Wagner, R., Rettenwander, D., Redhammer, G.J., Tippelt, G., Sabathi, G., Musso, M.E., Stanje, B., Wilkening, M., Suard, E., Amthauer, G. |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2016 |
| Předmět: | |
| Zdroj: | Inorganic Chemistry 'Inorganic Chemistry ', vol: 55, pages: 12211-12219 (2016) |
| ISSN: | 1520-510X 0020-1669 |
| Popis: | Li oxide garnets are among the most promising candidates for solid-state electrolytes in novel Li ion and Li metal based battery concepts. Cubic Li7La3Zr2O12 stabilized by a partial substitution of Zr4+ by Bi5+ has not been the focus of research yet, despite the fact that Bi5+ would be a cost-effective alternative to other stabilizing cations such as Nb5+ and Ta5+. In this study, Li7–xLa3Zr2–xBixO12 (x = 0.10, 0.20, ..., 1.00) was prepared by a low-temperature solid-state synthesis route. The samples have been characterized by a rich portfolio of techniques, including scanning electron microscopy, X-ray powder diffraction, neutron powder diffraction, Raman spectroscopy, and 7Li NMR spectroscopy. Pure-phase cubic garnet samples were obtained for x ≥ 0.20. The introduction of Bi5+ leads to an increase in the unit-cell parameters. Samples are sensitive to air, which causes the formation of LiOH and Li2CO3 and the protonation of the garnet phase, leading to a further increase in the unit-cell parameters. The incorporation of Bi5+ on the octahedral 16a site was confirmed by Raman spectroscopy. 7Li NMR spectroscopy shows that fast Li ion dynamics are only observed for samples with high Bi5+ contents. The cubic modification of Li7La3Zr2O12 can be stabilized by a by a partial substitution of Zr4+ by Bi5+. The incorporation of Bi5+ leads to an increase in the unit-cell parameters. Samples prepared by a low-temperature preparation route are sensitive to CO2 and H2O from air, causing a protonation of the garnet phase. 7Li NMR spectroscopy shows that fast translational Li ion dynamics are only observed for samples with high Bi5+ contents. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|