Jump to main content
Jump to site search

Issue 17, 2014
Previous Article Next Article

Speciation of Cr(III) in intermediate phases during the sol–gel processing of Cr-doped SrTiO3 powders

Author affiliations

Abstract

The local environment of Cr3+ during the sol–gel synthesis of 1% and 5% Cr3+-doped SrTiO3 (Cr3+:SrTiO3) bulk powders was systematically studied by structural characterization techniques and dopant-specific spectroscopies. After calcination at 800 °C, the precursors were annealed between 850 °C and 1050 °C for up to 6 h. We observe the formation of numerous phases in addition to the final product of SrTiO3. One of these is a metastable Ruddelsden–Popper phase (Sr2TiO4) that forms when the precursor is annealed at 1050 °C for less than 2 h. Electron paramagnetic resonance (EPR) spectroscopy reveals a new signal that correlates with appearance of the Sr2TiO4 phase and is consistent with Cr3+ substitution into the axially-compressed Ti4+ site in Sr2TiO4. The best agreement between experiment and the simulated EPR spectra of Cr3+:Sr2TiO4 is when |D| = 0.0207 cm−1, g = 1.9803 and g = 1.9793. The majority of the sample is converted to Cr3+:SrTiO3 with increasing annealing times at 1050 °C as detected by low-temperature emission and EPR spectroscopies, and powder X-ray diffraction.

Graphical abstract: Speciation of Cr(iii) in intermediate phases during the sol–gel processing of Cr-doped SrTiO3 powders

Back to tab navigation

Supplementary files

Publication details

The article was received on 01 Nov 2013, accepted on 06 Dec 2013 and first published on 06 Dec 2013


Article type: Paper
DOI: 10.1039/C3TA14475E
Citation: J. Mater. Chem. A, 2014,2, 6138-6145
  •   Request permissions

    Speciation of Cr(III) in intermediate phases during the sol–gel processing of Cr-doped SrTiO3 powders

    K. A. Lehuta and K. R. Kittilstved, J. Mater. Chem. A, 2014, 2, 6138
    DOI: 10.1039/C3TA14475E

Search articles by author

Spotlight

Advertisements