Achieving desired performance from self‐assembly of nanoparticles (NPs) is challenging due to the stochastic nature of interactions among the constituent building blocks. Self‐assembly of nano‐colloids through evaporation of particle‐laden droplets can be exploited to fabricate tailored nanostructures that add functionality and engineer the properties of manufactured components. The particle–particle and particle–solvent interactions, and delicate force balance among them are the main factors that define the pattern of the final 3D nanostructure. Here, a nanoparticle‐agnostic approach that allows the fabrication of nanostructures with precisely engineered patterns is introduced. Evaporative droplets of aqueous suspensions of pristine Carbon Nanotubes, Graphene Nanoplatelets, and Boron Nitride Nanotubes representing NPs of different elemental compositions, sizes, and shapes are investigated. Cellulose nanocrystals (CNCs) are used as a platform to make hybrid systems of CNC‐NP and utilize the repulsive‐attractive‐directional interactions in these multimaterial systems to enforce the desired final pattern between ring and disk. It is shown that irrespective of the type of NPs, the amphiphilicity of the hybrid system dictates the formation of deposited patterns. Finally, the effect of self‐assembled patterns on the functionality of multi‐material systems is demonstrated. The proposed method creates new capabilities in the precisely controlled nanostructures and facilitates smart self‐assembly systems.
Kinetically assembled binary nanoparticle networks
Embedding percolating networks of nanoparticles (NPs) within polymers is a promising approach for mechanically reinforcing polymers and for introducing novel electronic, transport, and catalytic properties into otherwise inert polymers. While such networks may be obtained through kinetic assembly of unary system of NPs, the ensuing structures exhibit limited morphologies. Here, we investigate the possibility of increasing the diversity of NP networks through kinetic assembly of multiple species of NPs. Using lattice Monte Carlo simulations we show that networks obtained from co-assembly of two NP species of different sizes exhibit significantly more diverse morphology than those assembled from a single species. In particular, we achieved considerable variations in the particle spatial distribution, proportions of intra- and interspecies contacts, fractal dimension, and pore sizes of the networks by simply modulating the stoichiometry of the two species and their intra and inter-species affinities. We classified these distinct morphologies into “integrated”, “coated”, “leaved”, and “blocked” phases, and provide relevant phase diagrams for achieving them. Our findings are relevant to controlled and predictable assembly of particle networks for creating multifunctional composites with improved properties.
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- Award ID(s):
- 1636356
- NSF-PAR ID:
- 10196681
- Date Published:
- Journal Name:
- Nanoscale
- Volume:
- 12
- Issue:
- 8
- ISSN:
- 2040-3364
- Page Range / eLocation ID:
- 5091 to 5102
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/c9nr09900j
