Articles
  • The phase relationship of Na+-beta-aluminas synthesized by a sol-gel process in the ternary system Na2O-Al2O3-Li2O 
  • Sung-Tae Lee, Seung-Gyun Kim, Min-Ho Jang, Sul-Hyee Hwang, Jung -Rim Haw and Sung-Ki Lim*
  • Department of Materials Chemistry and Engineering, Konkuk University, 1 Hwayang-dong, Gwangjin-gu, Seoul 143-701, South Korea
Abstract
Na+-beta"-alumina was synthesized by a sol-gel process in the ternary system Li2O-Na2O-Al2O3. In order to research the phase formation of Na+-beta"-alumina by varying the composition and calcination temperature in the range of pH 1-9, the sodium concentration was varied within the molar ratio range, [Na2O] : [Al2O3] = 1 : 4-1 : 8, and the calcination temperature was varied between 1100-1500 degrees C. The phase fraction of Na+-beta"-alumina indicated a tendency to increase continually to 1500 degrees C. It was shown that up to about 88%, in the molar ratio of [Na2O] : [Al2O3] = 1 : 5, the transient eutectic liquid in the Li2O-Na2O-Al2O3 system at about 1460 degrees C promoted the transformation of beta-alumina to beta"-alumina at higher temperatures. The average particle size (if the synthesized powder was 300-500 nm.

Keywords: Na+-beta ''-alumina; Sol-Gel process; Sodium/Sulfur battery

This Article

  • 2010; 11(1): 86-91

    Published on Feb 28, 2010