Nanocomposites Fe2O3/SiO2-preparation by sol-gel method and physical properties

被引：0

作者：

Niznansky, D ^{[1
]}

Viart, N ^{[1
]}

Rehspringer, JL ^{[1
]}

机构：

[1] IPCMS,GRP MAT INORGAN,F-67037 STRASBOURG,FRANCE

来源：

JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY | 1997年 / 8卷 / 1-3期

关键词：

sol-gel; magnetic nanocomposite; iron oxide; Mossbauer spectroscopy; Kerr effect;

D O I：

10.1023/A:1018359923896

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：

Magnetic nanocomposites gamma-Fe2O3/silica were prepared by a one-step sol-gel method. The sol was prepared by TEOS (tetraethyl orthosilicate) acid hydrolysis in the presence of an iron salt soluble in methanol. After gelation and drying, the transparent samples were characterized after treatment at different temperatures. The particle size, observed by HR TEM, was in the range of 2-10 nm and depended on Fe-concentration and heating temperature. Magnetic measurements showed either a ferromagnetic or a superparamagnetic behaviour and could be explained by the particle size. The dependence of the magnetic behaviour on the particle size was also studied by Mossbauer spectroscopy. The samples in which the Fe2O3 particle size was approximately 10 nm showed magnetic splitting (sextet) at room temperature, while smaller particles (2-3 nm) showed this splitting only at the temperature of liquid helium. The optomagnetic properties of the samples were also measured (Kerr effect).

引用

页码：615 / 618

页数：4