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Updated: Dec 12, 2025
10:37
Spatial Separation of Molecular Conformers and Clusters
Published on: January 9, 2014
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Atomic-scale phase separation induced clustering of solute atoms
Lianfeng Zou1, Penghui Cao2, Yinkai Lei3
1Department of Mechanical Engineering & Materials Science and Engineering Program, State University of New York, Binghamton, NY, 13902, USA.
Nature Communications
|August 10, 2020
Summary
This study reveals a novel nonchemical dealloying mechanism at the atomic scale, leading to solute atom clustering. It involves asymmetric adatom-substrate exchange barriers driving phase separation in alloys.
Area of Science:
- Materials Science
- Surface Science
- Nanotechnology
Background:
- Traditional dealloying relies on chemical dissolution and corrosion.
- Understanding atomic-scale processes is crucial for designing advanced materials.
Purpose of the Study:
- To report a novel nonchemical dealloying process.
- To elucidate the atomic mechanisms of solute atom clustering and phase separation.
Main Methods:
- Dynamic atomic-scale electron microscopy.
- Theoretical modeling and simulations.
- In-situ observation of adatom behavior.
Main Results:
- Demonstrated a nonchemical dealloying mechanism driven by asymmetric adatom-substrate exchange barriers.
- Observed the separation of Cu adatoms from a Cu-Au mixture, leaving an Au-rich phase.
- Characterized the nucleation, rotation, and amorphization-crystallization dynamics of gold clusters.
Conclusions:
- The findings present a new paradigm for dealloying beyond chemical dissolution.
- The process is governed by inherent atomic properties, suggesting broad applicability.
- This work provides fundamental insights into atomic-scale phase separation in multicomponent systems.
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