Journal of Sol-Gel Science and Technology

, Volume 75, Issue 3, pp 593–601 | Cite as

Structural characterisation of slightly Fe-doped SrTiO3 grown via a sol–gel hydrothermal synthesis

  • S. FuentesEmail author
  • P. Muñoz
  • N. Barraza
  • E. Chávez-ÁngelEmail author
  • C. M. Sotomayor Torres
Original Paper


A detailed structural study of the incorporation of Fe into SrTiO3 nanoparticles is reported. Slightly iron-doped strontium titanate nanoparticles with 0, 1, 3 and 5 mol% concentration of iron were grown using a sol–gel hydrothermal process and characterised using Raman scattering, X-ray photoelectron and X-ray diffraction spectroscopy. The amorphisation of the nanostructures was observed as the iron content increased, which was confirmed by the TEM images. The XPS results indicated that the oxidation states of the Sr atoms were maintained in 2+. However, a mixture of Fe3+ and Fe4+ atoms was observed as the Fe content increased, resulting in a significant number of oxygen vacancies in the perovskite structure. The analysis of Raman spectra indicated that the intensity, linewidth and frequency shift of the TO4 phonon can be used as an indicator of the Fe content as well as a local temperature probe for future thermal analysis.

Graphical abstract

Temperature evolution of the Raman spectra of STO:Fe 1 mol%. The peaks with star correspond to the second-order processes. (b) Temperature dependence of the TO4 phonon mode. Blue dots denote measured Raman spectra, and the red solid lines are the Lorentzian fits to respective spectra.


Strontium titanate Fe-doped Raman scattering XPS analysis 



The authors acknowledge the financial support from the FONDECYT grant under contract No. 1110555, the basal Financing program CONICYT FB0807 (CEDENNA). ECA and CMST gratefully acknowledge financial support from the Spanish MINECO projects nanoTHERM (Grant No. CSD2010-0044) and TAPHOR (MAT2012-31392), as well as partial support from the Severo Ochoa Program (MINECO, Grant SEV-2013-0295).


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Copyright information

© Springer Science+Business Media New York 2015

Authors and Affiliations

  1. 1.Departamento de Ciencias Farmacéuticas, Facultad de CienciasUniversidad Católica del NorteAntofagastaChile
  2. 2.Departamento de Física, Facultad de CienciasUniversidad de Santiago de Chile (USACH)SantiagoChile
  3. 3.Institut Catalá de Nanociencia i Nanotecnología (ICN2)Bellaterra, BarcelonaSpain
  4. 4.Institució Catalana de Recerca i Estudis Avançats (ICREA)BarcelonaSpain
  5. 5.Center for the Development of Nanoscience and Nanotechnology (CEDENNA)SantiagoChile

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