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Fabrication of Schottky Diodes on Zn-polar BeMgZnO/ZnO Heterostructure Grown by Plasma-assisted Molecular Beam Epitaxy
Published on: October 23, 2018
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High-Temperature Polymorphism and Band-Gap Evolution in BaZrS3
Ankit Jaiswal1,2, Konstantin A Sakharov1, Yulia Lekina3
1School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore.
Inorganic Chemistry
|December 9, 2024
Summary
Barium zirconium trisulfide (BZS) exhibits reversible high-temperature phase transitions, forming three distinct polymorphs with varying optoelectronic properties. Understanding these BZS polymorphs is key to developing advanced photovoltaic and LED materials.
Area of Science:
- Materials Science
- Solid-State Chemistry
- Crystallography
Background:
- Barium zirconium trisulfide (BZS) is a 3D perovskite with potential in optoelectronics.
- Conventionally, BZS is known in the orthorhombic Pnma symmetry.
- High-temperature behavior and polymorphism of BZS were not fully understood.
Purpose of the Study:
- To investigate the high-temperature polymorphs of BZS.
- To characterize the structural and optoelectronic properties of these polymorphs.
- To understand the reversibility of BZS polymorphic transitions.
Main Methods:
- Synchrotron X-ray diffraction
- Thermal analysis (Differential Scanning Calorimetry)
- Raman and absorption spectroscopy
Main Results:
- Three high-temperature polymorphs (II, III, IV) of BZS were identified with distinct stability ranges up to 700 °C.
- Phase transitions were accompanied by exothermic events.
- Direct band gap varied inversely with temperature for each polymorph (1.52–1.84 eV).
Conclusions:
- Polymorphic changes up to 600 °C were reversible upon cooling.
- This study provides a foundation for tuning BZS optoelectronic properties.
- Understanding BZS polymorphism enables the development of enhanced PV and LED materials.
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