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Title: Randomly Layered Superstructure of In2O3 Truncated Nano-Octahedra and Its High-Pressure Behavior
This study outlines the preparation and characterization of a unique superlattice composed of indium oxide (In2O3) vertex-truncated nano-octahedra, along with an exploration of its response to high-pressure conditions. Transmission electron microscopy and scanning transmission electron microscopy were employed to determine the average circumradius (15.2 nm) of these vertex-truncated building blocks and their planar superstructure. The resilience and response of the superlattice to pressure variations, peaking at 18.01 GPa, were examined by using synchrotron-based Wide-Angle X-ray Scattering (WAXS) and Small-Angle X-ray Scattering (SAXS) techniques. The WAXS data revealed no phase transitions, reinforcing the stability of the 2D superlattice comprised of random layers in alignment with a p31m planar symmetry as discerned by SAXS. Notably, the SAXS data also unveiled a pressure-induced, irreversible translation of octahedra and ligand interaction occurring within the random layer. Through our examination of these pressure-sensitive behaviors, we identified a distinctive translation model inherent to octahedra and observed modulation in the superlattice cell parameter induced by pressure. This research signifies a noteworthy advancement in deciphering the intricate behaviors of 2D superlattices under high pressure.  more » « less
Award ID(s):
1808383 1905422
PAR ID:
10500755
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Publisher / Repository:
ACS
Date Published:
Journal Name:
Journal of the American Chemical Society
Volume:
146
Issue:
12
ISSN:
0002-7863
Page Range / eLocation ID:
8598 to 8606
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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