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Updated: Nov 20, 2025
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Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
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Colloidal Metal Nanocrystals with Metastable Crystal Structures
Annemieke Janssen1, Quynh N Nguyen1, Younan Xia1,2,3
1School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia, 30332, USA.
Angewandte Chemie (International Ed. in English)
|January 21, 2021
Summary
Engineering metal nanocrystals with novel crystal structures, beyond traditional parameters, enhances their properties. This review explores synthesis strategies for metastable phases in noble metals, focusing on catalytic improvements.
Area of Science:
- Materials Science
- Nanotechnology
- Catalysis
Background:
- Conventional control over metal nanocrystals includes composition, size, shape, and defects.
- Crystal structure (phase) presents a novel parameter for property engineering.
- Metastable phases of noble metal nanocrystals offer unique properties compared to bulk counterparts.
Purpose of the Study:
- To review fabrication strategies for colloidal metal nanocrystals in metastable phases.
- To discuss the synthesis of noble metal nanocrystals in unconventional crystal structures.
- To highlight enhanced catalytic properties resulting from these engineered phases.
Main Methods:
- Introduction to atomic packing in noble metals.
- Discussion of five major synthetic approaches for colloidal nanocrystals in unconventional phases.
- Analysis of mechanistic insights and experimental controls in synthesis.
Main Results:
- Successful synthesis of noble metal nanocrystals in metastable phases.
- Demonstration of enhanced catalytic performance due to engineered crystal structures.
- Insights into synthetic mechanisms and control over nanocrystal formation.
Conclusions:
- Crystal structure is a powerful tool for tuning metal nanocrystal properties.
- Advanced synthetic strategies enable access to metastable phases with superior catalytic activity.
- Future research should address remaining challenges and explore new opportunities in this field.
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