Chemical synthesis of La0.7Sr0.3MnO3/silica homogeneous nanocomposites

被引：21

作者：

Huang, YH ^{[1
]}

Yan, CH ^{[1
]}

Wang, S ^{[1
]}

Luo, F ^{[1
]}

Wang, ZM ^{[1
]}

Liao, CS ^{[1
]}

Xu, GX ^{[1
]}

机构：

[1] Peking Univ, PKU HKU Joint Lab Rare Earth Mat & Bioinorgan Che, State Key Lab Rare Earth Mat Chem & Applicat, Beijing 100871, Peoples R China

来源：

JOURNAL OF MATERIALS CHEMISTRY | 2001年 / 11卷 / 12期

关键词：

D O I：

10.1039/b103922a

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

A soft chemistry process to prepare La0.7Sr0.3MnO3 (LSMO)/silica hybrid nanocomposites is reported. Homogeneous granular mixtures are obtained through a sol-gel chemical route by a single step. The precursor solution is comprised of complexes of La3+, Sr2+ and Mn2+ with ethylenediaminetetraacetic acid (EDTA) and tetraethoxysilane (TEOS). Silica is produced by an ammonia-catalyzed process, and LSMO is obtained by thermal decomposition of the complex precursor. Micrographs from scanning electron microscopy show well homogeneous solid mixtures of the two phases at the nanoscale level. XRD patterns and micro-FTIR analysis indicate that SiO2 exists in the composites independent of LSMO when calcined at low temperature, whereas Si-O-M (M=La, Sr and Mn) bonds are formed upon calcination above 800 degreesC. An enhanced magnetoresistance is observed for a 700 degreesC-calcined (LSMO)(SiO2)0.20 composite from 150 K up to room temperature.

引用

收藏

页码：3296 / 3299

页数：4

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