Trivalent cation conducting solid electrolytes with NASICON type structure, R1/3Zr2(PO4)3 (R = rare earth), were synthesized by a ball milling method and trivalent R3+ cation conducting properties were investigated. The trivalent ion conductivity of R1/3Zr2(PO4)3 was enhanced by about 3 times compared to the samples prepared by a conventional sol–gel method due to the improvement of the crystallinity of the solids. The macroscopic Sc3+ cation conducting behavior in Sc1/3Zr2(PO4)3, which showed the highest trivalent ion conductivity in R1/3Zr2(PO4)3 series, was directly demonstrated by a direct-current electrolysis method.

Trivalent Ion Conduction in NASICON-Type Solid Electrolyte Prepared by Ball Milling. S.Tamura, N.Imanaka, G.Adachi: Solid State Ionics, 2002, 154-155, 767-71