Na+ superionic conducting silicophosphate glass-ceramics - Review

Recent researches on structural control of the glass-ceramic Na+ superionic conductors 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. In addition, the results on control of the structure by bias crystallization of glasses in an electric field were presented.