Paper
25 February 2020 Fabrication of self-assembled nanoparticle cluster array using the surface affinity difference of isotropic droplets in nematic medium
Author Affiliations +
Proceedings Volume 11303, Emerging Liquid Crystal Technologies XV; 113030X (2020) https://doi.org/10.1117/12.2544057
Event: SPIE OPTO, 2020, San Francisco, California, United States
Abstract
We demonstrated a novel nanoparticle (NP) self-assembly method in a liquid crystal (LC) medium by exploiting two physical phenomena: (i) surface affinity contrast of isotropic pockets in nematic phase for ITO and self-assembled monolayer (SAM), and (ii) NP solubility contrast in isotropic and nematic phase. In the former phenomenon, the higher molecular roughness of ITO surface than SAM surface induced the higher surface affinity of isotropic pockets on the ITO surface. Hence, the isotropic pockets were anchored on the ITO islands of the patterned ITO substrate, while the nematic medium remained on the other area in which SAM was created. In the latter phenomenon, the uni-directional alignment in the bulk LC of nematic phase was mismatched with the one on the NP interface while the isotropic phase did not show any mismatch between the LC alignment in bulk and at the NP interface. The alignment mismatch in nematic phase resulted in the poorer NP solubility than it in isotropic phase. Hence, this large NP solubility contrast in two phases resulted in the NPs were confined to the isotropic pockets and dragged by the phase-boundary. By combining the two phenomena, we successfully fabricated the self-assembled NP cluster array on the ITO islands of the patterned ITO substrate. Since no electric or magnetic field is used in this method, it is applicable to a wide variety of NPs including ferroelectric, ferromagnetic etc. This method can potentially be utilized for fabrication of photonic crystals.
© (2020) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Jun-Seo Lee, Vitaly Petrovich Panov, and Jang-Kun Song "Fabrication of self-assembled nanoparticle cluster array using the surface affinity difference of isotropic droplets in nematic medium", Proc. SPIE 11303, Emerging Liquid Crystal Technologies XV, 113030X (25 February 2020); https://doi.org/10.1117/12.2544057
Advertisement
Advertisement
RIGHTS & PERMISSIONS
Get copyright permission  Get copyright permission on Copyright Marketplace
KEYWORDS
Nanoparticles

Glasses

Molecules

Liquid crystals

Silica

Interfaces

Photonic crystals

Back to Top