Pressure-induced amorphization and a new high density amorphous metallic phase in matrix-free Ge nanoparticles
File(s)
Accepted version
Supporting information
Author(s)
Type
Journal Article
Abstract
Over the last two decades, it has been demonstrated that size effects have significant consequences for the atomic arrangements and phase behavior of matter under extreme pressure. Furthermore, it has been shown that an understanding of how size affects critical pressure-temperature conditions provides vital guidance in the search for materials with novel properties. Here, we report on the remarkable behavior of small (under ∼5 nm) matrix-free Ge nanoparticles under hydrostatic compression that is drastically different from both larger nanoparticles and bulk Ge. We discover that the application of pressure drives surface-induced amorphization leading to Ge-Ge bond overcompression and eventually to a polyamorphic semiconductor-to-metal transformation. A combination of spectroscopic techniques together with ab initio simulations were employed to reveal the details of the transformation mechanism into a new high density phase-amorphous metallic Ge.
Date Issued
2015-10-12
Date Acceptance
2015-10-01
Citation
Nano Letters, 2015, 15 (11), pp.7334-7340
ISSN
1530-6992
Publisher
American Chemical Society
Start Page
7334
End Page
7340
Journal / Book Title
Nano Letters
Volume
15
Issue
11
Copyright Statement
This document is the Accepted Manuscript version of a Published Work that appeared in final form in Nano Letters, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://dx.doi.org/10.1021/acs.nanolett.5b02627
Subjects
Ge nanoparticles
Raman
X-ray absorption
amorphization
density functional theory calculations
high pressure
phase transformation
Publication Status
Published