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Ferromagnetism at 300 K in spin-coated films of Co doped anatase and rutile TiO2

R. Suryanarayanan·Vaman Naik·Parasuram Kharel·Punya Talgala·Ratna Naik
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Abstract

Thin films of Ti1-xCoxO2 (x=0 and 0.03) have been prepared on sapphire substrates by spin-on technique starting from metalorganic precursors. When heat treated in air at 550 and 700 C respectively, these films present pure anatase and rutile structures as shown both by X-ray diffraction and Raman spectroscopy. Optical absorption indicate a high degree of transparency in the visible region. Such films show a very small magnetic moment at 300 K. However, when the anatase and the rutile films are annealed in a vacuum of 1x10-5 Torr at 500 oC and 600 oC respectively, the magnetic moment, at 300 K, is strongly enhanced reaching 0.36 B/Co for the anatase sample and 0.68 B/Co for the rutile one. The ferromagnetic Curie temperature of these samples is above 350 K.

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R. Suryanarayanan, Vaman Naik, Parasuram Kharel, Punya Talgala, Ratna Naik. 2004-09-13. Ferromagnetism at 300 K in spin-coated films of Co doped anatase and rutile TiO2. https://doi.org/10.1016/j.ssc.2004.12.007

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