Oxygen-vacancies-related room-temperature ferromagnetism in polycrystalline bulk co-doped TiO2

被引：16

作者：

Kong, LG ^{[1
]}

Kang, JF ^{[1
]}

Wang, Y ^{[1
]}

Sun, L ^{[1
]}

Liu, LF ^{[1
]}

Liu, XY ^{[1
]}

Zhang, X ^{[1
]}

Han, RQ ^{[1
]}

机构：

[1] Peking Univ, Inst Microelect, Beijing 100871, Peoples R China

来源：

ELECTROCHEMICAL AND SOLID STATE LETTERS | 2006年 / 9卷 / 01期

关键词：

D O I：

10.1149/1.2130263

中图分类号：

O646 [电化学、电解、磁化学];

学科分类号：

081704 ;

摘要：

Room-temperature ferromagnetism (RTFM) is observed in the bulk CoxTi1-xO2-delta (0.06 <= x <= 0.1) samples synthesized by the solid-state reaction method for the mixed powder of Ti and Co oxides, followed by a 500 C furnace annealing process in a 10% hydrogen-argon mixture of ambient gases. The X-ray diffraction, X-ray photoelectron spectroscopy, and measurements of magnetic susceptibility, x, vs temperature, T, indicate polycrystalline Co-doped TiO2 anatase without Co clusters was fabricated. A phase transformation from CoTiO3 to CoxTi1-xO2-delta occurs after the hydrogenation process. These results are strong indications for formation of oxygen vacancies near the high spin Co2+ sites, and the formed oxygen vacancies are essential for the generation of RTFM in CoxTi1-xO2-delta. Based on these observations, ferromagnetism in bulk CoxTi1-xO2-delta anatase could be attributed to the exchange interaction between Co2+ mediated by oxygen vacancies near Co2+ sites, not being caused by Co clusters. (c) 2005 The Electrochemical Society. [DOI: 10.1149/1.2130263] All rights reserved.

引用

页码：G1 / G3

页数：3

共 20 条

[1] Anisotropy of ferromagnetism in Co-implanted rutile [J].

Akdogan, N ;

Rameev, BZ ;

Dorosinsky, L ;

Sozeri, H ;

Khaibullin, RI ;

Aktas, B ;

Tagirov, LR ;

Westphalen, A ;

Zabel, H .

JOURNAL OF PHYSICS-CONDENSED MATTER, 2005, 17 (34) :L359-L366

[2] Clusters and magnetism in epitaxial Co-doped TiO2 anatase [J].

Chambers, SA ;

Droubay, T ;

Wang, CM ;

Lea, AS ;

Farrow, RFC ;

Folks, L ;

Deline, V ;

Anders, S .

APPLIED PHYSICS LETTERS, 2003, 82 (08) :1257-1259

[3] Epitaxial growth and properties of MBE-grown ferromagnetic Co-doped TiO2 anatase films on SrTiO3(001) and LaAlO3(001) [J].

Chambers, SA ;

Wang, CM ;

Thevuthasan, S ;

Droubay, T ;

McCready, DE ;

Lea, AS ;

Shutthanandan, V ;

Windisch, CF .

THIN SOLID FILMS, 2002, 418 (02) :197-210

[4] Ferromagnetism in Fe-doped SnO2 thin films [J].

Coey, JMD ;

Douvalis, AP ;

Fitzgerald, CB ;

Venkatesan, M .

APPLIED PHYSICS LETTERS, 2004, 84 (08) :1332-1334

[5] Epitaxial growth of ferromagnetic Co:TiO2 thin films by co-sputtering [J].

Han, GC ;

Wu, YH ;

Tay, M ;

Li, KB ;

Guo, ZB ;

Chong, TC .

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS, 2004, 268 (1-2) :159-164

[6]

JAK MJJ, 2000, THESIS LEIDEN U LEID

[7] High Curie-temperature ferromagnetism in cobalt-implanted single-crystalline rutile [J].

Khaibullin, RI ;

Tagirov, LR ;

Rameev, BZ ;

Ibragimov, SZ ;

Yildiz, F ;

Aktas, B .

JOURNAL OF PHYSICS-CONDENSED MATTER, 2004, 16 (41) :L443-L449

[8] Formation of Co nanoclusters in epitaxial Ti0.96Co0.04O2 thin films and their ferromagnetism [J].

Kim, DH ;

Yang, JS ;

Lee, KW ;

Bu, SD ;

Noh, TW ;

Oh, SJ ;

Kim, YW ;

Chung, JS ;

Tanaka, H ;

Lee, HY ;

Kawai, T .

APPLIED PHYSICS LETTERS, 2002, 81 (13) :2421-2423

[9] Ferromagnetism induced by clustered Co in Co-doped anatase TiO2 thin films -: art. no. 017401 [J].

Kim, JY ;

Park, JH ;

Park, BG ;

Noh, HJ ;

Oh, SJ ;

Yang, JS ;

Kim, DH ;

Bu, SD ;

Noh, TW ;

Lin, HJ ;

Hsieh, HH ;

Chen, CT .

PHYSICAL REVIEW LETTERS, 2003, 90 (01)

[10] Synthesis and characterization of titania films on Mo(110) [J].

Lai, X ;

Guo, Q ;

Min, BK ;

Goodman, DW .

SURFACE SCIENCE, 2001, 487 (1-3) :1-8

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