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Abstract Checkerboard lattices—where the resulting structure is open, porous, and highly symmetric—are difficult to create by self-assembly. Synthetic systems that adopt such structures typically rely on shape complementarity and site-specific chemical interactions that are only available to biomolecular systems (e.g., protein, DNA). Here we show the assembly of checkerboard lattices from colloidal nanocrystals that harness the effects of multiple, coupled physical forces at disparate length scales (interfacial, interparticle, and intermolecular) and that do not rely on chemical binding. Colloidal Ag nanocubes were bi-functionalized with mixtures of hydrophilic and hydrophobic surface ligands and subsequently assembled at an air–water interface. Using feedback between molecular dynamics simulations and interfacial assembly experiments, we achieve a periodic checkerboard mesostructure that represents a tiny fraction of the phase space associated with the polymer-grafted nanocrystals used in these experiments. In a broader context, this work expands our knowledge of non-specific nanocrystal interactions and presents a computation-guided strategy for designing self-assembling materials.
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Air‐Liquid Interfacial Self‐Assembly of Two‐Dimensional Periodic Nanostructured Arrays
Abstract The large‐scale fabrication of two‐dimensional periodic nanostructures in high quality holds great promises for building novel nanoscale devices. They have been conventionally produced using interface‐mediated self‐assembly strategies such as the Langmuir‐Blodgett and oil‐water interfacial assembly methods, which however are limited by the stringent requirements for the hydrophilicity/hydrophobicity of the particle surface. In this article, we review the recent progress on the air‐liquid interfacial self‐assembly to demonstrate that such strategies are simple, inexpensive, effective, scalable, and versatile in the fabrication of two‐dimensional periodic nanostructured arrays. They can be successfully employed to assemble nanoparticles of various compositions and surface properties into periodic nanostructured monolayer films, which find many important applications, for example, in the construction of colorimetric sensors for gas, chemical, and biomedical detection.
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- Award ID(s):
- 1810485
- PAR ID:
- 10117873
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- ChemNanoMat
- Volume:
- 5
- Issue:
- 11
- ISSN:
- 2199-692X
- Format(s):
- Medium: X Size: p. 1338-1360
- Size(s):
- p. 1338-1360
- Sponsoring Org:
- National Science Foundation
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