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Interconversion of perovskite and fluorite structures in Ce-Sc-O system
Rakesh Shukla1, Ashok Arya, Avesh K Tyagi
1Chemistry Division, Bhabha Atomic Research Centre, Mumbai 400 085, India.
Inorganic Chemistry
|January 1, 2010
Summary
This study synthesized cerium scandate (CeScO(3)) perovskite oxide, revealing its semiconducting properties and potential for blue light emission. Doping with terbium (Tb3+) demonstrated efficient green light emission, highlighting its use in phosphors.
Area of Science:
- Solid-state chemistry
- Materials science
- Oxide synthesis
Background:
- Perovskite oxides are crucial for various applications.
- Understanding the synthesis and properties of novel perovskites like CeScO(3) is important.
- Cerium and Scandium oxides have unique electronic and optical properties.
Purpose of the Study:
- To synthesize and characterize cerium scandate (CeScO(3)) perovskite.
- To investigate its structural, electronic, and optical properties.
- To explore its potential as a host material for phosphors.
Main Methods:
- Two-step synthesis: combustion followed by vacuum heating with Zr sponge.
- Characterization: X-ray diffraction (XRD), high-temperature XRD, thermogravimetry, UV-Vis spectrophotometry, Raman spectroscopy.
- Computational analysis: First-principles calculations for band structure.
Main Results:
- Formation of a fluorite-type intermediate (Ce(0.5)Sc(0.5)O(1.75)).
- Reversible structural transformation between fluorite and perovskite phases via redox reaction.
- CeScO(3) identified as a semiconductor with a 3.2 eV band gap.
- Observed broad blue photoluminescence emission.
- Tb(3+)-doped CeScO(3) showed efficient green light emission.
Conclusions:
- CeScO(3) is a stable semiconducting oxide with tunable optical properties.
- It serves as a promising host material for luminescent applications.
- The study confirms the potential of CeScO(3) for efficient light emission, particularly green light when doped.
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