An investigation into the lithium ion dynamics of lithium lanthanum titanate using solid state NMR

The mobility of ions within the ceramic electrolyte Li 0.30La0.57□0.13TiO3 was probed using solid state NMR methods. The static quadrupolar and dipolar interaction values were measured for both 6Li and 7Li. Where relevant, the measured static interaction values were compared with those predicted by theory. The motional narrowing of the lineshape as a function of temperature was observed, showing that the lithium ions are mobile within the structure. Spin-lattice relaxation times were measured for both Li nuclei as a function of temperature to provide a measure of the relaxation mechanism as well as the activation energy for the ionic motion. It was found that the relaxation mechanism for 7Li was dominated by the quadrupolar interaction. For 6Li the relaxation mechanism could not be determined. The activation energies are measured for both nuclei using several theoretical models, and show agreement with past studies.