Formation of LaF3 microcrystals in sol-gel silica

Shinobu Fujihara, Chizuko Mochizuki, Toshio Kimura

Research output: Contribution to journalArticle

84 Citations (Scopus)

Abstract

A novel sol-gel process for silica/fluoride composites is described. Crystallization of LaF3 in the sol-gel silica has been investigated. Dry silica gels containing La3+ and trifluoroacetate ions (CF3COO-) were produced from tetramethylorthosilicate (TMOS), methanol, dimethylformamide, lanthanum acetate, trifluoroacetic acid, water and nitric acid. By heating the gels at temperatures above 300 °C, LaF3 microcrystals with a size of 10-30 nm were formed in the silica matrix. IR, XPS and TG-DTA analyses suggested that CF3COO- ions are coordinated to La3+ ions in the sols and the dried gels, leading to the formation of LaF3 by the thermal decomposition at elevated temperatures.

Original languageEnglish
Pages (from-to)267-274
Number of pages8
JournalJournal of Non-Crystalline Solids
Volume244
Issue number2
DOIs
Publication statusPublished - 1999 Mar 2

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Microcrystals
Silica Gel
microcrystals
silica gel
Sol-gels
Trifluoroacetic Acid
Silica
Ions
Silicon Dioxide
acids
Gels
gels
silicon dioxide
Trifluoroacetic acid
Nitric Acid
Lanthanum
Dimethylformamide
ions
Silica gel
nitric acid

ASJC Scopus subject areas

  • Ceramics and Composites
  • Electronic, Optical and Magnetic Materials

Cite this

Formation of LaF3 microcrystals in sol-gel silica. / Fujihara, Shinobu; Mochizuki, Chizuko; Kimura, Toshio.

In: Journal of Non-Crystalline Solids, Vol. 244, No. 2, 02.03.1999, p. 267-274.

Research output: Contribution to journalArticle

Fujihara, Shinobu ; Mochizuki, Chizuko ; Kimura, Toshio. / Formation of LaF3 microcrystals in sol-gel silica. In: Journal of Non-Crystalline Solids. 1999 ; Vol. 244, No. 2. pp. 267-274.
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