The Synthesis and Properties of the Chemically Oxidized Perovskite, La1-xSrxCoO3-δ(0.5≤x≤0.9)

Joseph E. Sunstrom IV, K. V. Ramanujachary, Martha Greenblatt, Mark Croft

Research output: Contribution to journalArticlepeer-review

66 Scopus citations


The series of La1-xSrxCoO3-δ(0.5≤x≤0.9) perovskites have been prepared using the Pechini gel technique. The products were chemically oxidized by stirring in a sodium hypobromite solution. The samples have been characterized by powder X-ray diffraction, thermal analysis, iodometric titration, Co K edge X-ray absorption spectroscopy, temperature-dependent SQUID magnetic susceptibility, and temperature-dependent electrical resistivity. The Sr-rich samples (x>0.7) have the brownmillerite-type structure prior to oxidation and the cubic perovskite structure after treatment with sodium hypobromite. Iodometric titration shows as much as a ~14% increase in Co(IV) concentration in the Sr-rich samples after chemical oxidation. The Co K edge spectra show that there is very little change in the formal cobalt valence with increasing Sr content. The effective magnetic moments of the oxidized compounds level off with increasing Sr concentration. All of the chemically oxidized samples exhibit small-bandgap semiconducting behavior. The data lead to the postulation of an equilibrium between Co(IV) and O-in the series.

Original languageEnglish (US)
Pages (from-to)388-397
Number of pages10
JournalJournal of Solid State Chemistry
Issue number2
StatePublished - Sep 1998
Externally publishedYes

All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Ceramics and Composites
  • Condensed Matter Physics
  • Physical and Theoretical Chemistry
  • Inorganic Chemistry
  • Materials Chemistry


Dive into the research topics of 'The Synthesis and Properties of the Chemically Oxidized Perovskite, La1-xSrxCoO3-δ(0.5≤x≤0.9)'. Together they form a unique fingerprint.

Cite this