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Author Spotlight: Exploring Self-Assembled MOF-Polymer Composites
Published on: June 14, 2024
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Coloration in Supraparticles Assembled from Polyhedral Metal-Organic Framework Particles
Junwei Wang1, Yang Liu2, Gudrun Bleyer1
1Institute of Particle Technology, Friedrich-Alexander Universität Erlangen-Nürnberg, 91058, Erlangen, Germany.
Angewandte Chemie (International Ed. in English)
|February 7, 2022
Summary
Supraparticles made of metal-organic framework (MOF) particles exhibit structural color due to light interference. Even with varied MOF shapes, local ordering suffices for visible macroscopic coloration.
Area of Science:
- Materials Science
- Nanotechnology
- Optics
Background:
- Supraparticles are colloidal crystals with tunable properties.
- Structural color in supraparticles arises from light interference with building blocks.
- Metal-organic frameworks (MOF) offer versatile building block potential.
Purpose of the Study:
- To investigate structural coloration in supraparticles composed of metal-organic framework (MOF) particles.
- To analyze how building block size and internal structure affect coloration.
- To understand the mechanism behind angle-dependent coloration in MOF supraparticles.
Main Methods:
- Confined self-assembly to create supraparticles.
- Analysis of structural coloration as a function of MOF building block size and structure.
- Microscopic and optical characterization of MOF supraparticles.
Main Results:
- Supraparticles with high structural order were assembled using uniform, polyhedral MOF particles.
- Angle-dependent coloration was observed and attributed to ordered, onion-like layers on the outermost regions.
- Macroscopic coloration was visible in all supraparticle dispersions, regardless of MOF particle shape variations.
Conclusions:
- Local ordering within supraparticles is sufficient to generate observable interference effects and structural color.
- The formation of ordered surface layers on MOF building blocks plays a key role in supraparticle coloration.
- MOF supraparticles present a promising platform for developing novel photonic materials.
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