Trivalent ion conducting solid electrolytes

A trivalent ion conduction in solids was realized with Sc2(WO4)3-type structure by the consideration of the stability and size of mobile trivalent ions and a structure to reduce the electrostatic interaction between the framework and the mobile ionic species as much as possible. Among the tungstates and the molybdates with the Sc2(WO4)3-type structure, Sc2(WO4)3 and Sc2(MoO4)3 were found to hold the most suitable lattice size for trivalent ion migration in the individual series. By the dc electrolysis and EPMA measurements, the mobile species was clearly identified to be trivalent ions in the Sc2(WO4)3-type structure.