ABSTRACT
Pressure-dependent phase transitions of In2Se3 bulk powders and nanowire samples were studied at room temperature using synchrotron X-ray diffraction and a diamond anvil cell. γ-In2Se3, metastable under ambient conditions, transforms into to the stable high pressure β phase between 2.8 and 3.2 GPa in bulk powder samples and at slightly higher pressures, between 3.2 and 3.7 GPa, in nanowire samples. While the γ phase bulk modulus is similar to that of the β phase, the decrease due to pressure in the unit cell parameter ratio, c/a, is less than half the decrease seen in the β phase. First-principles calculations show that γ-In2Se3 has a higher energy and unit-cell volume than β-In2Se3, consistent with the experimental observations.
Acknowledgements
The authors thank the beamline 12.2.2 team at ALS/LBNL and Zhongwu Wang at CHESS for their assistance with the XRD experiments.
Disclosure statement
No potential conflict of interest was reported by the authors.