Reaction Mechanism on the Synthesis of BaTiO3 by Direct Wet Process

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J. Korean Ceram. Soc. > Volume 26(3); 1989 > Article

Journal of the Korean Ceramic Society 1989;26(3): 371.

BaTiO3 습식직접합성 반응기구에 관한 연구

이경희, 이병하, 김대웅¹

명지대학교 공과대학 무기재료공학과
¹고려화학(주) 중앙연구소

Reaction Mechanism on the Synthesis of BaTiO3 by Direct Wet Process

ABSTRACT

The purpose of this experiment is to elucidate the reaction mechanism concerning to the formation of crystalline BaTiO3 synthesized by adding the pH control agent(KOH soln) in TiCl4 and BaCl2 solution (Wet direct synthetic method). In this expeirment, it is identified that the amorphous barium-titanate having Ba-O-Ti bonding is formed above pH5 due to the -OH- ion and Ti-gel is formed below pH5 due to the polymerization of metatitanic acid. The bonding of the amorphous Ba-O-Ti is identified by FT-IR spectrum and crystallization temperature is about 82$0^{circ}C$. If the pH of the above system according to the -OH- ion concentration is above 13.8, the polymerized metatitanic acid will be depolymerized and produce [TiO3]2+ion and crystalline BaTiO3 is formed by reacting the produced [TiO3]-- ion with the active Ba++ ion.