Effect of substitution (Ta, Al, Ga) on the conductivity of Li7La3Zr2O12

Abstract Cubic garnets of composition Li 6.75 La 3 Zr 1.75 Ta 0.25 O 12 , Li 6.15 La 3 Zr 1.75 Ta 0.25 Al 0.2 O 12 , and Li 6.15 La 3 Zr 1.75 Ta 0.25 Ga 0.2 O 12 were prepared from a co-precipitated precursor and consolidated by hot-pressing to a relative density of ∼96–98%. The total Li-ion conductivities at 298 K and activation energies (in parentheses) of Li 6.75 La 3 Zr 1.75 Ta 0.25 O 12 , Li 6.15 La 3 Zr 1.75 Ta 0.25 Al 0.2 O 12 and Li 6.15 La 3 Zr 1.75 Ta 0.25 Ga 0.2 O 12 were 0.87 mS cm −1 (0.22 eV), 0.37 mS cm −1 (0.30 eV) and 0.41 mS cm −1 (0.27 eV), respectively. The above results suggest that cubic stabilizing substitutions outside of the Li-ion sub-lattice are preferable to obtain faster Li-ion conductivity.