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DOE OSTI · 1615596

Evaporative Assembly: Dual-Scale Nanostructures via Evaporative Assembly (Adv. Mater. Interfaces 7/2020)

Srivastava, Sunita·Wahith, Zaibudeen A.·Gang, Oleg·Colosqui, Carlos E.·Bhatia, Surita R.
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Abstract

In article number 1901954, Sunita Srivastava, Surita R. Bhatia, and co-workers demonstrate that evaporative assembly of functionalized nanoparticles can yield striking dual-scale hierarchical structures. Regular microscale stripes of nanoparticle monolayers with hexagonal nanoscale order are obtained on physically and chemically homogeneous substrates through evaporation of a suspension of DNAfunctionalized nanoparticles with a charged shell. The stripe width, spacing and nanoparticle ordering can be controlled by varying nanoparticle concentration and can be described by a simple analytical model. The results indicate that the interplay between “stick-slip” motion of the droplet contact line and Coulombic and steric nanoparticle interactions control the formation of the observed structures. Finally, this work demonstrates a simple cost-effective mask-free method for fabricating nanostructured 2D materials and metasurfaces for applications ranging from energy conversion/storage to optoelectronics and nanophotonics.

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Srivastava, Sunita, Wahith, Zaibudeen A., Gang, Oleg, Colosqui, Carlos E., Bhatia, Surita R.. 2020-04-14. Evaporative Assembly: Dual-Scale Nanostructures via Evaporative Assembly (Adv. Mater. Interfaces 7/2020). https://doi.org/10.1002/admi.202070036

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