Enhancement of lithium ion conduction in the cubic rare earth oxide

A new type of lithium ion conducting solid electrolyte based on a cubic rare earth oxide was developed by co-doping LiNO3 and KNO3 into a (Gd1−xNdx)2O3 solid, which possesses large interstitial open spaces within the structure. Among the samples prepared, 0.6(Gd0.4Nd0.6)2O3–0.16LiNO3–0.24KNO3 exhibits the highest lithium ion conductivity of 8.05 × 10−2 and 1.35 × 10−3 S cm−1 at 400 and 100 °C, respectively, which is comparable to that of the LISICON materials. Pure Li+ ion conduction was successfully demonstrated by the dc electrolysis method.