Related Experiment Videos
Oxygen-deficient strontium cobaltate, SrCoO2.64
Akihiko Nakatsuka1, Akira Yoshiasa, Noriaki Nakayama
1Department of Advanced Materials Science and Engineering, Faculty of Engineering, Yamaguchi University, Ube 755-8611, Japan. tuka@po.cc.yamaguchi-u.ac.jp
Summary
Single crystals of strontium cobaltate (SrCoO3-x) were grown using the floating-zone method. X-ray diffraction revealed a cubic perovskite structure with significant oxygen deficiency, indicating positional disorder in oxygen atoms.
Area of Science:
- Materials Science
- Solid State Chemistry
- Crystallography
Background:
- Strontium cobaltate (SrCoO3-x) is a complex oxide with potential applications.
- Understanding its crystal structure and oxygen stoichiometry is crucial for its properties.
- Previous studies have indicated variability in oxygen content and its impact.
Purpose of the Study:
- To grow high-quality single crystals of strontium cobaltate.
- To determine the precise crystal structure and oxygen stoichiometry of the grown crystals.
- To investigate the nature of oxygen atom disorder within the perovskite lattice.
Main Methods:
- Single crystal growth via the floating-zone method under controlled oxygen flow.
- X-ray diffraction (XRD) for structural analysis and symmetry determination.
- Refinement of oxygen atom site occupancy to determine chemical composition.
Main Results:
- Successfully grew single crystals of strontium cobaltate (SrCoO3-x).
- Confirmed crystallization in the cubic perovskite structure with Pm-3m symmetry.
- Determined the chemical composition as SrCoO2.64 (x = 0.36(3)) due to oxygen deficiency.
- Observed anisotropic displacement ellipsoids for oxygen atoms, suggesting positional disorder.
Conclusions:
- The floating-zone method is effective for growing SrCoO3-x single crystals.
- SrCoO3-x exhibits significant oxygen deficiency and cubic perovskite structure.
- Oxygen atoms display positional disorder, oriented perpendicular to Co-O bonds, influencing material properties.