Formation of LaF3 microcrystals in sol-gel silica

被引：96

作者：

Fujihara, S ^{[1
]}

Mochizuki, C ^{[1
]}

Kimura, T ^{[1
]}

机构：

[1] Keio Univ, Fac Sci & Technol, Dept Appl Chem, Kohoku Ku, Yokohama, Kanagawa 2238522, Japan

来源：

JOURNAL OF NON-CRYSTALLINE SOLIDS | 1999年 / 244卷 / 2-3期

关键词：

D O I：

10.1016/S0022-3093(99)00009-5

中图分类号：

TQ174 [陶瓷工业]; TB3 [工程材料学];

学科分类号：

0805 ; 080502 ;

摘要：

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 degrees 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. (C) 1999 Elsevier Science B.V. All rights reserved.

引用

页码：267 / 274

页数：8

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