The quasi 2-dimensional Sc2(WO4)3 type structure and the 3-dimensional NASICON-type R1/3Zr2(PO4)3 (R = Al3+, rare earths) series were prepared and their trivalent ion conducting characteristics were compared. Among the Sc2(WO4)3 type and the NASICON type series, the solid electrolytes with Sc3+ as a migrating species showed the highest ion conductivity. Especially, the NASICON type phosphate series holds such advantages of having a considerable high relative density and also more than seven times as high hardness compared with the Sc2(WO4)3 type series, promising applications for various types of devices were greatly expected.

Rare Earth Ion Conduction in Tungstate and Phosphate Solids. N.Imanaka, G.Y.Adachi: