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Updated: Aug 13, 2026
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Synthesis and Characterization of Supramolecular Colloids
Published on: April 22, 2016
Self-assembly of colloidal diamond via the depletion interaction
Min Jae Kim1, Xinhang Shen2, Min Kyung Lee1
1Department of Chemical and Biomolecular Engineering, New York University, Brooklyn, NY 11201.
Summary
We developed a faster, non-site-specific method to create colloidal diamond crystals using tetrahedrally lobed patchy particles (TLPPs) and depletion interactions, overcoming kinetic barriers in DNA-mediated self-assembly for photonic materials.
Area of Science:
- Materials Science
- Nanotechnology
- Crystallography
Background:
- Colloidal crystals with cubic diamond structure are key for 3D photonic band-gap materials.
- Previous DNA-mediated self-assembly faced kinetic barriers due to coordination requirements.
Purpose of the Study:
- To demonstrate an entropically guided, non-site-specific route to colloidal diamond using tetrahedrally lobed patchy particles (TLPPs).
- To overcome kinetic limitations in self-assembly for photonic applications.
Main Methods:
- Assembly of TLPPs using polymer micelles (Pluronic F127) as depletants.
- Characterization via optical microscopy, Monte Carlo simulations, and umbrella sampling.
- Permanent fixation of structures using DNA hybridization and UV-induced thymine photodimerization.
Main Results:
- Achieved cubic-diamond crystals with faster assembly (order of magnitude) and lower particle concentrations compared to DNA-mediated systems.
- Confirmed 3D diamond order and ABC stacking through detailed structural analysis.
- Demonstrated reduced rotational entropic barriers via depletion strength manipulation.
Conclusions:
- Entropically guided depletion assembly offers a more efficient route to colloidal diamond structures.
- The method enables rapid formation of ordered structures suitable for photonic materials.
- Permanent fixation allows for further processing into inverse photonic lattices.
