Synthesis, Crystallization Behaviors and Conductivity of <TEX>$beta$</TEX>-Alumina from Aluminum Isopropoxide and Sodium Hydroxide

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J. Korean Ceram. Soc. > Volume 32(9); 1995 > Article

Journal of the Korean Ceramic Society 1995;32(9): 1076.

Aluminum Isopropoxide와 Sodium Hydroxide로부터 $beta$-Alumina의 합성과 결정화 과정 및 전도도

양유철, 박용민, 김형욱, 손영국

부산대학교 공과대학 무기재료공학과

Synthesis, Crystallization Behaviors and Conductivity of $beta$-Alumina from Aluminum Isopropoxide and Sodium Hydroxide

ABSTRACT

A mixture of aluminum isopropoxide (Al(OC3H7i)3) solution and sodium hydroxide (NaOH) solution was hydrolyzed in the range between pH 1~14. the powder obtained from sol-gel process was calcined at several temperatures and crystallization behaviors of various samples were investigated. The hydrolyzed sols of pH 1~6 wre clear, or near clear. On the other hand, powder precipitated from sols of pH 7~14. The sample obtained from pH 3 solution crystallized via complicated route, and $beta$-Al2O3 and $beta$"-Al2O3 phases appeared at lower temperature than samples from other pH conditions. And the quantity of remained $beta$"-Al2O3 phase after heat treatment at 150$0^{circ}C$ was more than samples from other pH conditions. After sintering, ionic conductivities were 1.3$times$10-4S.cm-1 to 0.76$times$10-4S.cm-1.0-4S.cm-1.

Key words: ${\beta}$-Al2O3, ${\beta}$"-Al2O3, Sol-gel, pH conditions, Ionic conductivity