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Updated: May 31, 2026
11:54
Growth and Electrostatic/chemical Properties of Metal/LaAlO3/SrTiO3 Heterostructures
Published on: February 8, 2018
Structural study of La(0.75)Sr(0.25)CrO(3) at high temperatures
Keka R Chakraborty1, S M Yusuf, P S R Krishna
1Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai 400085, India.
Summary
Strontium-doped lanthanum chromite (La(0.75)Sr(0.25)CrO(3)) exhibits complex phase coexistence at high temperatures. This study reveals structural transitions crucial for solid oxide fuel cell applications.
Area of Science:
- Materials Science
- Solid-state Chemistry
- Crystallography
Background:
- LaCrO(3) is a parent perovskite material.
- Doping with Sr influences structural properties.
- Understanding high-temperature phase behavior is key for applications.
Purpose of the Study:
- Investigate the high-temperature structural phase transitions of La(0.75)Sr(0.25)CrO(3).
- Quantify phase fractions and determine thermal expansion coefficients.
- Assess the material's suitability for solid oxide fuel cells.
Main Methods:
- High-temperature neutron diffraction.
- Quantitative Rietveld analysis.
- Thermal expansion measurements.
Main Results:
- Orthorhombic to rhombohedral transition shifts to lower temperatures upon Sr doping.
- Two-phase coexistence (orthorhombic and rhombohedral) observed from 300-470 K.
- Three-phase coexistence (orthorhombic, rhombohedral, and cubic) observed from 480-1400 K, with varying phase fractions.
- Thermal expansion coefficients determined for all phases.
Conclusions:
- La(0.75)Sr(0.25)CrO(3) displays complex phase behavior at elevated temperatures.
- The identified phase transitions and thermal expansion properties are critical for its use in solid oxide fuel cells.
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