The effects of sol-gel processes on Na⁺ ionic conductivity for the silicophosphate in the Na₂O-Y₂O₃-P₂O₅-SiO₂ system

Abstract

Sodium superionic conductors in the Na₂O-Y₂O₃-P₂O₅-SiO₂ system were synthesized by sol-gel methods and difference in ionic conductivity of sintered compacts between synthetic processes were discussed. When the sol-gel processes using moist N₂ were employed, highly homogeneous xerogel was obtained and sintering of the xerogel led to dense compact. However, the sintered sample did not have higher conductivity than samples obtained by other sol-gel processes. The OH residue in the bulk would prevent conduction of sodium ion.