Improving the room temperature ionic conductivity of Al-Li7La3Zr2O12 ceramics by Ba and Y or Ba and W co-doping.

Li 6.5+x La 3-x Ba x Zr 1.9 Y 0.1 Al 0.2 O 12 (0 ≤ x ≤ 0.05), Li 6.42+y La 2.98 Ba 0.02 Zr 2 - y Y y Al 0.2 O 12 (0 ≤ y ≤ 0.14) and Li 6.42-2z La 2.98 Ba 0.02 Zr 2-z W z Al 0.2 O 12 (0.05 ≤ z ≤ 0.45) ceramics were synthesized by the solid-state reaction method. The effects of the Ba, Y and W content on the crystallographic structure, morphology, the relative density and shrinkage, and the total ionic conductivity of the synthesized ceramics were studied, respectively. Li 6.5+x La 3-x Ba x Zr 1.9 Y 0.1 Al 0.2 O 12 (x = 0.01–0.05), Li 6.42+y La 2.98 Ba 0.02 Zr 2 - y Y y Al 0.2 O 12 (y = 0.06–0.12) and Li 6.42-2z La 2.98 Ba 0.02 Zr 2-z W z Al 0.2 O 12 (z = 0.05–0.45) ceramics were found to be of single cubic phase. Co-substitution of Ba and Y or of Ba and W for La and Zr can eliminate grain boundary, accelerate densification, and improve the ionic conductivity. The relative density and the total ionic conductivity at room temperature of Li 6.52 La 2.98 Ba 0.02 Zr 1.9 Y 0.1 Al 0.2 O 12 and Li 5.72 La 2.98 Ba 0.02 Zr 1.65 W 0.35 Al 0.2 O 12 ceramics are 93.23% and 2.02 × 10−4 S/cm, and 96.32% and 6.35 × 10−4 S/cm, respectively. [ABSTRACT FROM AUTHOR]