THE ELECTRICAL AND THERMAL-PROPERTIES OF SODIUM-SULFATE MIXED WITH LITHIUM-SULFATE, YTTRIUM SULFATE, AND SILICON DIOXIDE

Sodium sulfate mixed with lithium sulfate, yttrium sulfate, and silicon dioxide was prepared. The thermal and electrical properties of its phases were investigated. The Na//2SO//4-Li//2SO//4-Y//2(SO//4)//3-SiO//2 samples are similar to the Na//2SO//4-I phase (a high temperature phase), which is appreciably effective for Na** plus ionic conduction. Phase transformation was considerably suppressed by mixing. Electromotive force (EMF) was measured, using Na//2SO//4-Li//2SO//4-Y//2(SO//4)//3-SiO//2 as a solid electrolyte, by constructing an SO//2 gas concentration cell. The measured EMFs at 823 and 773 K were n fairly good accordance with the calculated EMFs for inlet SO//2 gas concentraton between 330 ppm and 1%, and 500 ppm and 0. 5%, respectively.