High-Pressure Phase Transition of Metastable Wurtzite-Like CuInSe2 Nanocrystals
Shinhyo Bang1, Juejing Liu2, Bipeng Wang3
1Department of Chemistry, Washington State University, Pullman, Washington 99164, United States.
Chemistry of Materials : a Publication of the American Chemical Society
|April 14, 2025
Summary
This study reveals that metastable wurtzite-like copper indium selenide (CuInSe2) nanocrystals transform into a disordered NaCl-like structure at 7.7 GPa. This new phase remains stable even after pressure is released.
Area of Science:
- Materials Science
- Solid-State Physics
- Nanotechnology
Background:
- Ternary I-III-VI2 semiconductors like copper indium selenide (CuInSe2) possess diverse structural polymorphs.
- Metastable wurtzite-like CuInSe2 nanocrystals are of interest due to their unique properties.
Purpose of the Study:
- To investigate the pressure-induced phase transitions of metastable wurtzite-like CuInSe2 nanocrystals.
- To understand the structural evolution under high pressure and decompression.
Main Methods:
- Synchrotron X-ray diffraction
- Pair distribution function analysis
- Density functional theory calculations
Main Results:
- A phase transition from wurtzite-like (Pmc21) to NaCl-like (Fm3m) structures occurred at 7.7 GPa.
- The cation-disordered NaCl-like phase was observed to be stable upon decompression.
- Bulk modulus calculations indicated size-dependent behavior in nanocrystals compared to bulk materials.
Conclusions:
- The study elucidates the phase stability of CuInSe2 nanocrystals under pressure.
- Findings contribute to understanding and engineering functional materials under extreme conditions.
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