Synthesis and ionic conductivity of new high Li ion content garnets, LnSr2Ta2Li7O12 (Ln = La, Pr, Nd, Sm, Gd)

JOURNAL OF ALLOYS AND COMPOUNDS

卷:670

Article

Howard, M. A.¹  Clemens, O.^1,2,3  Parvathy, A. S.^2,3  Anderson, P. A.¹  Slater, P. R.¹ 

[1] Univ Birmingham, Sch Chem, Birmingham B15 2TT, W Midlands, England

[2] Tech Univ Darmstadt, Joint Res Lab Nanomat, Jovanka Bontschits Str 2, D-64287 Darmstadt, Germany

[3] Karlsruher Inst Technol, Inst Nanotechnol, Hermann von Helmholtz Pl 1, D-76344 Eggenstein Leopoldshafen, Germany

关键词: Inorganic materials;    Oxide materials;    Ionic conduction;    X-ray diffraction;   

DOI  :  10.1016/j.jallcom.2016.02.012

来源: Elsevier

【 摘 要 】

In this paper we report the synthesis and Li ion conductivity of the new high Li content garnet phases LnSr(2)Ta(2)Li(7)O(12) (Ln = La, Pr, Nd, Sm or Gd). Close inspection of the X-ray diffraction patterns indicate that these systems are mostly composed of the ordered tetragonal garnet phase, along with a small amount of cubic garnet. The presence of a small amount of cubic garnet phase can most likely be correlated with partial Li loss on synthesis as well as some degree of H+/Li(+)exchange. The latter was supported by results from variable temperature X-ray diffraction studies and thermogravimetric analysis. The adoption of the tetragonal garnet structure by these new systems highlights further that in order to accommodate 7 Lithium ions within the garnet structure, then cation ordering must occur to prevent short Li-Li interactions. In line with other tetragonal garnet systems, the Li ion conductivity is shown to be low, as a result of this ordered Li distribution. (C) 2016 Elsevier B.V. All rights reserved.

【 授权许可】

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