Controlled transformation of paramagnetism to room-temperature ferromagnetism in cobalt-doped titanium dioxide

被引：41

作者：

Manivannan, A ^{[1
]}

Glaspell, G ^{[1
]}

Seehra, MS ^{[1
]}

机构：

[1] W Virginia Univ, Dept Phys, Morgantown, WV 26506 USA

来源：

JOURNAL OF APPLIED PHYSICS | 2003年 / 94卷 / 10期

关键词：

D O I：

10.1063/1.1622991

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

Samples of Co0.1Ti0.9O2-delta (anatase) prepared by the sol-gel technique are found to be paramagnetic at room temperature, with the magnetic susceptibility following Curie-Weiss law in the investigated range of 2-370 K. However, transformation from paramagnetism to room-temperature ferromagnetism (RTFM) is observed by hydrogenation of the sample at 573 K. The increase in the hydrogenation time from 1 to 6 h increases the remanance, and the Curie temperature similar or equal to470 K is determined by extrapolation. X-ray photoelectron spectroscopy and transmission electron microscopy of the hydrogenated samples failed to detect Co nanoparticles, suggesting that the observed RTFM in the hydrogenated samples may be intrinsic. (C) 2003 American Institute of Physics.

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页码：6994 / 6996

页数：3

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