The cover photo describing the crystal structure of Na5YSi4O12 with glass-ceramic Na+ superionic conductors. As discussed by Toshinori Okura, these glass-ceramic conductors have great potential and are one of the most important groups of solid electrolytes, not only because of its practical usefulness for advanced batteries but also for its three-dimensional ionic conducting nature.
Development of Na+ superionic conducting Na5YSi4O12-type glass-ceramics
Department of Applied Chemistry, School of Advanced Engineering, Kogakuin University, 2665-1 Nakano, Hachioji-shi, Tokyo 192-0015, Japan
Adv. Mater. Lett., 2019, 10 (2), pp 85-90
Publication Date (Web): Dec 19, 2018
Copyright © 2019 VBRI Press
This review article describes a series of studies on the glass-ceramic Na+ superionic conductors with Na5YSi4O12 (N5)-type structure synthesized using the composition formula of Na3+3x-yR1-xPySi3-yO9 for a variety of rare earth elements, R, under the appropriate composition parameters. Recent researches on structural control of the Na+ superionic conducting glass-ceramics are also introduced. The optimum conditions for crystallization were discussed with reference to the conduction properties and the preparation of crack-free N5-type glass-ceramics. The effects of Si substitution with the various elements with tetrahedral oxygen coordination structure and Y substitution with the various R elements were also discussed on ionic conductivity of N5-type glass-ceramics, respectively.
Superionic conductor, glass-ceramics, crystallization, Na5YSi4O12-type, microstructure.