Controlled Molecular Assembly Via Dynamic Confinement of Solvent
Assembly from ultrasmall solution droplets follows a different dynamic from that of larger scales. Using an independently controlled microfluidic probe in an atomic force microscope, subfemtoliter aqueous droplets containing polymers produce well-defined features with dimensions as small as tens of nanometers. The initial shape of the droplet and the concentration of solute within the droplet play significant roles in the final assembly of polymers due to the ultrafast evaporation rate and spatial confinement by the small droplets. These effects are used to control the final molecular assembly in terms of feature geometry and distribution and packing of individual molecules within the features. This work introduces new means of control over molecular assembly, bringing us closer to programmable synthesis for chemistry and materials science. The outcomes pave the way for three-dimensional (3D) nanoprinting in additive manufacturing.
J. Zhang et al., "Controlled Molecular Assembly Via Dynamic Confinement of Solvent," Journal of Physical Chemistry Letters, vol. 9, no. 21, pp. 6232-6237, American Chemical Society (ACS), Nov 2018.
The definitive version is available at https://doi.org/10.1021/acs.jpclett.8b02442
Electrical and Computer Engineering
Keywords and Phrases
Atomic force microscopy; Polymers, Aqueous droplets; Evaporation rate; Final assembly; Microfluidic probes; Molecular assembly; Small droplets; Spatial confinement; Threedimensional (3-d), Drop formation
International Standard Serial Number (ISSN)
Article - Journal
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