Skip to main content
SpringerLink
Log in

Spectroscopic investigation on tetrahedral Co2+ in thin-film CoFe2O4

  • Original Paper: Functional coatings, thin films and membranes (including deposition techniques)
  • Published:
Journal of Sol-Gel Science and Technology Aims and scope Submit manuscript

Abstract

CoFe2O4 has been attracting attention for its ferrimagnetism applicable to spin transfer, resonance imaging, drug delivery etc. CoFe2O4 thin films were synthesized on Si(100) substrates by using a sol–gel deposition process. The CoFe2O4 specimen produced by post-annealing in air at 800 °C showed flat surface and polycrystalline grains with no secondary phase. The specimen exhibited magnetic hysteresis curve with magnetization up to 415 emu/cm3 and coercivity of 1.7 kOe. Such a large magnetization implies migration of a number of Co2+ ions from octahedral to tetrahedral sites of the spinel lattice. The distribution of Co2+ ions among tetrahedral and octahedral sites of CoFe2O4 was estimated by curve-fitting analysis on the Raman scattering spectrum of the specimen. The result suggests 30% of the Co2+ ions residing in the tetrahedral sites. The coexistence of Co2+ ions in both tetrahedral and octahedral sites of CoFe2O4 was also detectable by using Co 2p X-ray photoelectron spectroscopy.

The CoFe2O4 thin-film specimen deposited on Si(100) substrate through a sol–gel process exhibited surface flatness and phase-pure polycrystalline grains. The specimen showed magnetic hysteresis curve with magnetization up to 415 emu/cm3, coercivity of 1.7 kOe and remnant magnetization of 170 emu/cm3. The observed magnetization exceeded theoretical value expected for pure inverse spinel CoFe2O4 and can be explained in terms of migration of a fraction of Co2+ ions from octahedral to tetrahedral sites of the spinel lattice. The inversion parameter of the CoFe2O4 specimen was estimated to be 0.70 through a curve-fitting on its Raman scattering spectrum. The curve-fitting analysis on Co 2p XPS spectrum of the specimen turned out to be supportive of the Raman analysis.

Highlights

  • CoFe2O4 thin films with high crystalline quality have been fabricated on Si(100) substrates by using a sol–gel technique and post-annealing in air at 800 °C.

  • Thin-film CoFe2O4 specimen exhibits magnetization (415 emu/cm3) that is larger than theoretical value (380 emu/cm3) expected for pure inverse spinel CoFe2O4.

  • The enhanced magnetization of CoFe2O4 is ascribed to the migration of Co2+ ions to the tetrahedral sites of the spinel lattice.

  • The inversion parameter of CoFe2O4 is estimated to be 0.70 through a curve-fitting analysis on the Raman scattering spectrum of the specimen.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5

Similar content being viewed by others

References

  1. Chandramohan P, Srinivasan MP, Velmurugan S, Narasimhan SV (2011) J Solid State Chem 184:89

    Article  Google Scholar 

  2. Georgiadou V, Tangoulis V, Arvanitidis I, Kalogirou O, Dendrinou-Samara C (2015) J Phys Chem C 119:8336

    Article  Google Scholar 

  3. Nappini S, Magnano E, Bondino F, Pis FI, Barla A, Fantechi E, Pineider F, Sangregorio C, Vaccari L, Venturella L, Baglioni P (2015) J Phys Chem C 119:25529

    Article  Google Scholar 

  4. Dun C, Xi G, Zhang Y, Zhao T, Liu Y, Heng X, Yao L (2018) Ceram Int 44:20984

    Article  Google Scholar 

  5. Thang PD, Rijnders G, Blank DHA (2007) J Magn Magn Mater 310:2621

    Article  Google Scholar 

  6. Kumar P, Sharma SK, Knobel M, Singh M (2010) J Alloy Compd 508:115

    Article  Google Scholar 

  7. Yadav SP, Shinde SS, Kadam AA, Rajpure KY (2013) J Alloy Compd 555:330

    Article  Google Scholar 

  8. Soeya S, Hayakawa J, Takahashi H, Ito K, Yamamoto C, Kida A, Asano H, Matsui M (2002) Appl Phys Lett 80:823

    Article  Google Scholar 

  9. Phase DM, Tiwari S, Prakash R, Dubey A, Sathe VG, Choudhary RJ (2006) J Appl Phys 100:123703

    Article  Google Scholar 

  10. Indhrajothi R, Prakash I, Venkateswarlu M, Satyanarayana N (2015) New J Chem 39:4601

    Article  Google Scholar 

  11. Tiwari S, Choudhary RJ, Prakash R, Phase DM (2007) J Phys: Condens Matter 19:176002

    Google Scholar 

  12. Wang Z, Downs RT, Pischedda V, Shetty R, Saxena SK, Zha CS, Zhao YS, Schiferl D, Waskowska A (2003) Phys Rev B 68:094101

    Article  Google Scholar 

  13. Sharma D, Khare N (2014) Appl Phys Lett 105:032404

    Article  Google Scholar 

  14. Carta D, Casula MF, Falqui A, Loche D, Mountjoy G, Sangregorie C, Corrias A (2009) J Phys Chem C 113:8606

    Article  Google Scholar 

  15. Li R, Sun C, Liu J, Zhen Q (2017) RSC Adv 7:50546

    Article  Google Scholar 

  16. Kim KJ, Lee JH, Koh TY, Kim MH (2016) Electro Acta 200:84

    Article  Google Scholar 

  17. Kim KJ, Koh TY (2016) J Sol-Gel Sci Technol 77:528

    Article  Google Scholar 

Download references

Acknowledgements

This work was supported by Konkuk University in the program year of 2017.

Author information

Authors and Affiliations

  1. Department of Physics, Konkuk University, Seoul, 05029, Korea

    Kwang Joo Kim & Jongho Park

Authors
  1. Kwang Joo Kim
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Jongho Park
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Kwang Joo Kim.

Ethics declarations

Conflict of interest

The authors declare that they have no conflict of interest.

Additional information

Publisher’s note: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Kim, K.J., Park, J. Spectroscopic investigation on tetrahedral Co2+ in thin-film CoFe2O4. J Sol-Gel Sci Technol 92, 40–44 (2019). https://doi.org/10.1007/s10971-019-05099-9

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s10971-019-05099-9

Keywords

Search

Navigation