Switching on fast lithium ion conductivity in garnets: the structure and transport properties of Li3+xNd3Te2-xSbxO12

M.P. O'Callaghan, A.S. Powell, J.J. Titman, G.Z. Chen, E.J. Cussen

Research output: Contribution to journalArticlepeer-review

128 Citations (Scopus)

Abstract

Polycrystalline samples of the garnets Li3+xNd3Te2-xSbxO12 have been prepared by high temperature solid state synthesis. X-ray and neutron powder diffraction data show that all compounds crystallize in the space group Ia3j d with lattice parameters in the range 12.55576(12) Å for x ) 0.05 to 12.6253(2) Å for x ) 1.5. The lithium is distributed over a mixture of oxide tetrahedra and heavily distorted octahedra. Increasing the lithium content in these compounds leads to the introduction of vacancies onto the tetrahedral position and an increasing concentration of lithium found in the octahedra. The latter exhibit considerable positional disorder with two lithium cations positions within each octahedron. Impedance measurements show fast ion conduction with an activation energy of ca. 0.59(6) eV that is largely invariant with composition. Solid-state Li NMR measurements indicate that there is no exchange of lithium between the different coordination environments. These results indicate that lithium conduction in the garnet structure occurs exclusively via a network of edge-linked distorted oxide octahedra and that the tetrahedrally coordination lithium plays no part in the transport properties.
Original languageEnglish
Pages (from-to)2360-2369
Number of pages10
JournalChemistry of Materials
Volume20
Issue number6
DOIs
Publication statusPublished - 25 Mar 2008

Keywords

  • garnets
  • ion conductivity
  • lithium

Fingerprint

Dive into the research topics of 'Switching on fast lithium ion conductivity in garnets: the structure and transport properties of Li3+xNd3Te2-xSbxO12'. Together they form a unique fingerprint.

Cite this