Assembly of Covalent Organic Frameworks into Colloidal Photonic Crystals
Javier Fonseca1,2, Lingxin Meng1,2, Pedro Moronta3
1Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC, and Barcelona Institute of Science and Technology, Campus UAB, 08193 Bellaterra, Barcelona, Spain.
Journal of the American Chemical Society
|September 6, 2023
Summary
Researchers created porous photonic crystals using porous covalent organic frameworks (COFs). The size of COF particles and adsorbed species tune the crystal
Area of Science:
- Materials Science
- Nanotechnology
- Chemistry
Background:
- Colloidal self-assembly is key for new materials like photonic crystals (PhCs).
- Porous materials offer tunable properties for advanced applications.
Purpose of the Study:
- To utilize porous covalent organic frameworks (COFs) as building blocks for novel porous PhCs.
- To investigate the tunability of PhC properties through COF particle size and pore adsorption.
Main Methods:
- Fabrication of porous PhCs using COF colloidal particles.
- Characterization of the face-centered cubic (fcc) arrangement of the assembled structures.
- Tuning of Bragg reflection by controlling COF particle size and adsorbate species.
Main Results:
- Successfully fabricated porous PhCs with an fcc arrangement from COF particles.
- Demonstrated tunability of Bragg reflection by varying COF particle size.
- Showed that species adsorbed within COF pores can alter the Bragg reflection.
Conclusions:
- Porous COFs are effective colloidal building blocks for creating functional PhCs.
- The developed method allows for precise control over PhC optical properties.
- This approach opens avenues for developing advanced colloidal PhCs with tailored functionalities.
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