Characteristics of $TiO_2$ Powders Prepared by Freeze Drying Method

동결건조법으로 제조한 $TiO_2$의 특성

  • 윤기현 (연세대학교 요업공학과) ;
  • 박승순 (연세대학교 요업공학과)
  • Published : 1988.03.01

Abstract

Extremely fine $TiO_2$ powders were synthesized from titanium chloride by the precipitation and freeze drying method. The phase transformation and electrical conductivity were investigated as a function of temperature. X-ray analysis showed that the phase transformation of the synthesized powder from the anatase to rutile occured at 64$0^{\circ}C$ and finished at 92$0^{\circ}C$ due to small particle size and large specific surface area. The activation energy obtained from electrical conductivity vs. temperature was about 1.63eV. This relatively large value was due to porosity in the specimen.

Keywords

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