El-Shinawi Hany, Cussen Edmund J, Corr Serena A
School of Chemistry, WestCHEM, University of Glasgow, Glasgow G12 8QQ, UK.
WestCHEM, Department of Pure and Applied Chemistry, The University of Strathclyde, Thomas Graham Building, 295 Cathedral Street, Glasgow, G1 1XL, UK.
Dalton Trans. 2017 Jul 25;46(29):9415-9419. doi: 10.1039/c7dt01573a.
Fast ion conducting garnet materials have been identified as promising electrolytes for all solid-state batteries. However, reliable synthetic routes to materials with fully elucidated cation site occupancies where an enhancement in lithium conductivity is observed remains a challenge. Ca-Incorporation is developed here as a promising approach to enhance the ionic conductivity of garnet-type LiLaZrTaO phases. Here we present a new sol-gel synthetic strategy as a facile route to the preparation of materials of a desired stoichiometry optimized for Li conductivity. We have found that the ionic conductivity of LiLaZrTaO is increased by a factor of four by the addition of 0.2 mol of Ca per formula unit. Ca is incorporated in the garnet lattice where it has no effect on the sinterability of the material and is predominately located at the La sites. We anticipate that the ease of our synthetic route and the phases presented here represents a starting point for the further realization of solid state electrolyte compositions with similarly high Li conductivities using this methodology.
快离子传导石榴石材料已被确定为全固态电池中很有前景的电解质。然而，要找到可靠的合成路线来制备阳离子位点占有率完全明确且锂电导率有所提高的材料仍然是一项挑战。在此，钙掺入被开发为一种有前景的方法，用于提高石榴石型LiLaZrTaO相的离子电导率。本文我们提出一种新的溶胶 - 凝胶合成策略，作为一种简便的途径来制备针对锂电导率优化的所需化学计量比的材料。我们发现，每 formula unit 添加 0.2 mol 的钙可使 LiLaZrTaO 的离子电导率提高四倍。钙掺入石榴石晶格中，对材料的烧结性没有影响，且主要位于镧位点。我们预计，我们合成路线的简便性以及本文所呈现的相代表了使用该方法进一步实现具有同样高锂电导率的固态电解质组合物的起点。
