The influence of hydrogen annealing on magnetism of Co-doped TiO2 films prepared by sol-gel method

被引:13
作者
Liu, L. F. [1 ]
Kang, J. F. [1 ]
Wang, Y. [1 ]
Tang, H. [1 ]
Kong, L. G. [1 ]
Sun, L. [1 ]
Zhang, X. [1 ]
Han, R. Q. [1 ]
机构
[1] Peking Univ, Inst Microelect, Beijing 100871, Peoples R China
基金
中国国家自然科学基金;
关键词
room-temperature ferromagnetism; Co-doped TiO2; sol-gel method; hydrogenation;
D O I
10.1016/j.jmmm.2006.05.006
中图分类号
T [工业技术];
学科分类号
08 ;
摘要
Co-doped TiO2 (CoxTi1-xO2, 0.05 <= x <= 0.2) films have been prepared on Si (0 0 1) substrates by sol-gel method. When heat treated in air, CoxTi1-xO2 films are non-ferromagnetic at room temperature. However, after further annealed in a flowing hydrogen atmosphere, CoxTi1-xO2 films show room-temperature ferromagnetism (RTFM). Measurements of magnetization (M) vs. temperature (T), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) fail to detect Co clusters in the hydrogenated Co0.1Ti0.9O2 films, suggesting that RTFM in the hydrogenated Co0.1Ti0.9O2 films may be intrinsic. But, metal Co appears in the hydrogenated Co0.2Ti0.8O2 films, showing that RTFM in the hydrogenated Co0.2Ti0.8O2 films is as least partly due to metal Co. These results indicate that hydrogen annealing can produce room-temperature ferromagnetism in CoxTi1-xO2 films, but it should be carefully designed to avoid the formation of metal Co in the hydrogenated CoxTi1-xO2 films. (c) 2006 Elsevier B.V. All rights reserved.
引用
收藏
页码:85 / 89
页数:5
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