Synthesis of shape-controlled ferromagnetic CrO2 nanoparticles by reaction in micelles of Cr6+-PVA polymer chelates

被引：15

作者：

Biswas, S. ^{[1
]}

Ram, S. ^{[1
]}

机构：

[1] Indian Inst Technol, Ctr Mat Sci, Kharagpur 721302, W Bengal, India

来源：

MATERIALS CHEMISTRY AND PHYSICS | 2006年 / 100卷 / 01期

关键词：

synthesis of CrO2; prismatic or ellipsoidal shape crO(2) nanoparticles; ferromagnetic nanoparticles; tetragonal CrO2;

D O I：

10.1016/j.matchemphys.2005.11.031

中图分类号：

T [工业技术];

学科分类号：

08 [工学];

摘要：

A chemical reaction of CrO3 with polymer molecules of poly vinyl alcohol (PVA) and sucrose in water is explored to synthesize CrO2 (D-4h(14) : P4(2)/mnm tetragonal crystal structure) of shape-controlled ferromagnetic particles. Under hot conditions, small species of Cr6+-PVA polymer chelates react in divided groups in micelles, resulting in a Cr4+-polymer complex, which retains in isolated groups of micelles dispersed in the water. When heating (after aging and drying), the polymer bums out at 300-400 degrees C in air, leaving behind a pure Cro(2) of prismatic or ellipsoidal shape. Average diameter varies in such particles from 50 to 300 nm depending on the final temperature. (c) 2005 Elsevier B.V. All rights reserved.

引用

页码：6 / 9

页数：4

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