Synthesis and Na+ conduction properties of Na5YSi4O12-type glass-ceramics

This review article describes a series of studies on glass-ceramic Na+ superionic conductors with the Na5YSi4O12 (N5)-type structure and with a Na3+3x−yR1−xPySi3−yO9 composition, where R is a rare earth element. Recent research into the structural control of Na+ superionic conducting glass-ceramics is introduced. The effects of substituting Si with other elements exhibiting tetrahedral oxygen coordination and substituting Y with various rare earth elements are also discussed in the context of the ionic conductivity of these N5-type glass-ceramics.