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Towards understanding the lithium transport mechanism in garnet-type solid electrolytes: Li+ ions exchanges and their mobility at octahedral/tetrahedral sites

Journal Article


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Abstract


  • The cubic garnet-type solid electrolyte Li7La3Zr2O12 with aliovalent

    doping exhibits a high ionic conductivity, reaching up to ∼10−3 S/cm at room

    temperature. Fully understanding the Li+ transport mechanism including Li+ mobility

    at different sites is a key topic in this field, and Li7−2x−3yAlyLa3Zr2−xWxO12 (0 ≤ x ≤ 1)

    are selected as target electrolytes. X-ray and neutron diffraction as well as ac impedance

    results show that a low amount of aliovalent substitution of Zr with W does not

    obviously affect the crystal structure and the activation energy of Li+ ion jumping, but it

    does noticeably vary the distribution of Li+ ions, electrostatic attraction/repulsion, and

    crystal defects, which increase the lithium jump rate and the creation energy of mobile

    Li+ ions. For the first time, high-resolution NMR results show evidence that the 24d,

    96h, and 48g sites can be well-resolved. In addition, ionic exchange between the 24d

    and 96h sites is clearly observed, demonstrating a lithium transport route of 24d−96h−

    48g−96h−24d. The lithium mobility at the 24d sites is found to dominate the total

    ionic conductivity of the samples, with diffusion coefficients of 10−9 m2 s−1 and 10−12

    m2 s−1 at the octahedral and tetrahedral sites, respectively.

Authors


  •   Wang, Da-Wei (external author)
  •   Zhong, Guiming (external author)
  •   Pang, Wei Kong.
  •   Guo, Zaiping
  •   Li, Yixiao (external author)
  •   Mcdonald, Matthew J. (external author)
  •   Fu, Riqiang (external author)
  •   Mi, Jin-Xiao (external author)
  •   Yang, Yong (external author)

Publication Date


  • 2015

Citation


  • Wang, D., Zhong, G., Pang, W. Kong., Guo, Z., Li, Y., Mcdonald, M. J., Fu, R., Mi, J. & Yang, Y. (2015). Towards understanding the lithium transport mechanism in garnet-type solid electrolytes: Li+ ions exchanges and their mobility at octahedral/tetrahedral sites. Chemistry of Materials, 27 (19), 6650-6659.

Scopus Eid


  • 2-s2.0-84944088906

Ro Full-text Url


  • http://ro.uow.edu.au/context/aiimpapers/article/2636/type/native/viewcontent

Ro Metadata Url


  • http://ro.uow.edu.au/aiimpapers/1634

Has Global Citation Frequency


Number Of Pages


  • 9

Start Page


  • 6650

End Page


  • 6659

Volume


  • 27

Issue


  • 19

Place Of Publication


  • United States

Abstract


  • The cubic garnet-type solid electrolyte Li7La3Zr2O12 with aliovalent

    doping exhibits a high ionic conductivity, reaching up to ∼10−3 S/cm at room

    temperature. Fully understanding the Li+ transport mechanism including Li+ mobility

    at different sites is a key topic in this field, and Li7−2x−3yAlyLa3Zr2−xWxO12 (0 ≤ x ≤ 1)

    are selected as target electrolytes. X-ray and neutron diffraction as well as ac impedance

    results show that a low amount of aliovalent substitution of Zr with W does not

    obviously affect the crystal structure and the activation energy of Li+ ion jumping, but it

    does noticeably vary the distribution of Li+ ions, electrostatic attraction/repulsion, and

    crystal defects, which increase the lithium jump rate and the creation energy of mobile

    Li+ ions. For the first time, high-resolution NMR results show evidence that the 24d,

    96h, and 48g sites can be well-resolved. In addition, ionic exchange between the 24d

    and 96h sites is clearly observed, demonstrating a lithium transport route of 24d−96h−

    48g−96h−24d. The lithium mobility at the 24d sites is found to dominate the total

    ionic conductivity of the samples, with diffusion coefficients of 10−9 m2 s−1 and 10−12

    m2 s−1 at the octahedral and tetrahedral sites, respectively.

Authors


  •   Wang, Da-Wei (external author)
  •   Zhong, Guiming (external author)
  •   Pang, Wei Kong.
  •   Guo, Zaiping
  •   Li, Yixiao (external author)
  •   Mcdonald, Matthew J. (external author)
  •   Fu, Riqiang (external author)
  •   Mi, Jin-Xiao (external author)
  •   Yang, Yong (external author)

Publication Date


  • 2015

Citation


  • Wang, D., Zhong, G., Pang, W. Kong., Guo, Z., Li, Y., Mcdonald, M. J., Fu, R., Mi, J. & Yang, Y. (2015). Towards understanding the lithium transport mechanism in garnet-type solid electrolytes: Li+ ions exchanges and their mobility at octahedral/tetrahedral sites. Chemistry of Materials, 27 (19), 6650-6659.

Scopus Eid


  • 2-s2.0-84944088906

Ro Full-text Url


  • http://ro.uow.edu.au/context/aiimpapers/article/2636/type/native/viewcontent

Ro Metadata Url


  • http://ro.uow.edu.au/aiimpapers/1634

Has Global Citation Frequency


Number Of Pages


  • 9

Start Page


  • 6650

End Page


  • 6659

Volume


  • 27

Issue


  • 19

Place Of Publication


  • United States