Preparation of silver ion conducting polycrystals by mechanical milling process

We applied, the ball-milling process to the preparation of the silver ion conductors, RbAg4I5, KAg4I5, NH4Ag4I5, and Ag7I4PO4. Only 45min ball milling of a mixture of Rbl and beta-AgI led to the formation of RbAg4I5 phase, and the obtained RbAg4I5 phase showed a high ion conductivity of 2.6 x10(-1)Scm(-1) at room temperature. The conductivity and the activation energy for conduction, which was obtained temperature dependence of conductivity, were almost same values reported by Owens [2], For the composition 80AgI . 20Ag(3)PO(4), which corresponds to that of Ag7I4PO4, ball milling for longer than 190h led to the formation of an unknown new crystalline phase, and the new phase showed a high ion conductivity of 6 x 10(-2) Scm(-1) at room temperature. The conductivity was higher than that of the crystalline Ag7I4PO4 phase which was reported by Takahashi [4].