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Occurrence and stability of ferromagnetism in chemically synthesized cobalt doped TiO2

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Abstract

We report the development of ferromagnetism in ∼30 nm sized well-characterized Ti1−x Co x O2 powders with x = 0.00015–0.006 and its absence for x > 0.006. In addition, these studies show the effect of Co doping on the structural stability and anatase to rutile phase transformation. X-ray diffraction data of samples synthesized by a wet chemical method and annealed at 450 °C indicate a limited solubility of ∼1.2% for Co in the anatase TiO2 matrix, and with further increase, the CoTiO3 phase is formed along with increased presence of rutile TiO2. The bandgap (∼3.23 eV) of the anatase TiO2 remained almost unchanged for x < 0.006, but decreased rapidly for x ≥ 0.006 approaching 2.8 eV for x = 0.03. The magnetic data from Ti1−x Co x O2 samples with x = 0.006 showed a coercivity H c ∼ 150 Oe and a weak magnetic moment of 0.2 μB/ion at 300 K. The ferromagnetism of Ti0.994Co0.006O2 with open hysteresis loops continue up to a high superparamagnetic blocking temperature T B ∼ 675 K, above which a superparamagnetic behavior was observed. Systematic changes in the structural, magnetic and optical properties suggest that Co doping is an excellent method to tailor the physical properties of TiO2 nanoparticles.

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References

  1. Y. Matsumoto, M. Murakami, T. Shono, T. Hasegawa, T. Fukumura, M. Kawasaki, P. Ahmet, T. Chikyow, S. Koshihara, H. Koinuma, Science 291, 854 (2001)

    Article  CAS  Google Scholar 

  2. S.R. Shinde, S.B. Ogale, S.D. Sarma, J.R. Simpson, H.D. Drew, S.E. Lofland, C. Lanci, J.P. Buban, N.D. Browning, V.N. Kulkarni, J. Higgins, R.P. Sharma, R.L. Greene, T. Venkatesan, Phys. Rev. B 67, 115211 (2003)

    Article  Google Scholar 

  3. J.D. Bryan, S.M. Heald, S.A. Chambers, D.R. Gamelin, J. Am. Chem. Soc. 126, 11640 (2004)

    Article  CAS  Google Scholar 

  4. H. Toyosaki, T. Fukumura, Y. Yamada, K. Nakjima, T. Chikyow, T. Hasegawa, H. Koinuma, M. Kawasaki, Nat. Mater. 3, 221 (2004)

    Article  CAS  Google Scholar 

  5. J.S. Higgins, S.R. Shinde, S.B. Ogale, T. Venkatesan, R.L. Green, Phys. Rev. B 69, 073201 (2004)

    Article  Google Scholar 

  6. W.K. Park, R.J. Ortega-Hertogs, J.S. Moodera, A. Punnoose, M.S. Seehra, J. Appl. Phys. 91, 8093 (2002)

    Article  CAS  Google Scholar 

  7. V. Shuthanandan, S. Thevuthasan, S.M. Heald, T. Droublay, M.H. Engelhard, T.C. Kasper, D.E. McCready, L. Saraf, S.A. Chambers, B.S. Mun, N.M. Hamdan, P. Nachimuthu, B. Taylor, R.P. Sears, B. Sinkovic, Appl. Phys. Lett. 84, 4466 (2004)

    Article  Google Scholar 

  8. J.Y. Kim, J.H. Park, B.G. Park, H.J. Noh, S.J. Oh, J.S. Yang, D.H. Kim, S.D. Bu, T.W. Noh, H.J. Lin, H.H. Heish, C.T. Chen, Phys. Rev. Lett. 90, 017401 (2003)

    Article  Google Scholar 

  9. K.A. Griffin, A.B. Pakamov, C.M. Wang, S.M. Heald, K.M. Krishnan, Phys. Rev. Lett. 94, 157204 (2005)

    Article  CAS  Google Scholar 

  10. M. Osada, Y. Ebina, K. Fukuda, K. Ono, K. Takada, K. Yamaura, E. Takayama-Muromachi, T. Sasaki, Phys. Rev. B 73, 153301 (2006)

    Article  Google Scholar 

  11. K.A. Griffin, M. Varela, S.J. Pennycook, A.B. Pachomov, K.M. Krsihnan, J. Appl. Phys. 99, 08M114 (2006)

    Article  Google Scholar 

  12. R.A. Spurr, H. Myers, Anal. Chem. 29, 760 (1957)

    Article  CAS  Google Scholar 

  13. R.D. Shannon, C.T. Prewitt, Acta Crystallogr., Sect. B: Struct. Crystallogr. Cryst. Chem. 25, 925 (1969)

    Article  CAS  Google Scholar 

  14. G. Kortum, Reflectance Spectroscopy (Springer-Verlag, New York, 1969)

    Google Scholar 

  15. D.A. Schwartz, N.S. Norberg, Q.P. Nguyen, J.M. Parker, D.R. Gamelan, J. Am. Chem. Soc. 125, 13205 (2003)

    Article  CAS  Google Scholar 

  16. N.H. Hong, W. Prellier, J. Sakai, A. Ruyter, J. Appl. Phys. 95, 7378 (2004)

    Article  Google Scholar 

  17. B.S. Jeong, Y.W Heo, D.P. Norton, J.G. Kelly, R. Rairigh, A.F. Hebard, J.D. Budai, Y.D. Park, Appl. Phys. Lett. 84, 2608 (2004)

    Article  CAS  Google Scholar 

  18. S.A. Chambers, S. Thevuthasan, R.F.C. Farrow, R.F. Marks, J.U. Thiele, L. Folks, M.G. Samant, A.J. Kellock, N. Ruzycki, D.L. Ederer, U. Diebold, Appl. Phys. Lett. 79, 3467 (2001)

    Article  CAS  Google Scholar 

  19. J. Hays, A. Punnoose, R. Baldner, M.H. Engelhard, J. Peloquin, K.M. Reddy, Phys. Rev. B 72, 075203 (2005)

    Article  Google Scholar 

  20. J.M.D. Coey, A.P. Douvalis, C.B. Fitzgerald, M. Venkatesan, Appl. Phys. Lett. 84, 1332 (2004)

    Article  CAS  Google Scholar 

  21. J.M.D. Coey, M. Venkatesan, C.B. Fitzgerald, Nat. Mater. 4, 173 (2005)

    Article  CAS  Google Scholar 

  22. A. Punnoose, M. Seehra, N. Shah, T. Phanthavady, G.P. Huffman, Phys. Rev. B 69, 054425 (2004)

    Article  Google Scholar 

  23. M.S. Seehra, A. Punnoose, Phys. Rev. B 64, 132410 (2001)

    Article  Google Scholar 

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Acknowledgements

This research was supported in part by grants from, NSF-Idaho-EPSCoR program (EPS-0447689), Research Corporation, NSF-CAREER program (DMR-0449639) and the DoE-EPSCoR program (DE-FG02-04ER46142) at Boise State University. We are thankful to Jason Hays from Boise State University for helpful discussions and careful proof reading of the manuscript.

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  1. Department of Physics, Boise State University, Boise, ID, 83725-1570, USA

    K. M. Reddy & A. Punnoose

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  1. K. M. Reddy
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  2. A. Punnoose
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Correspondence to A. Punnoose.

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Reddy, K.M., Punnoose, A. Occurrence and stability of ferromagnetism in chemically synthesized cobalt doped TiO2 . J Mater Sci: Mater Electron 18, 1137–1142 (2007). https://doi.org/10.1007/s10854-007-9127-6

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  • DOI: https://doi.org/10.1007/s10854-007-9127-6

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