Templated self-assembly of gold nanoparticles in smectic liquid crystals confined at 3D printed curved surfaces

Mackenzie O'Keefe; Jane Bernadette Denise M. Garcia; Abeco J. Rwakabuba; Timothy M. Otchy; Daniel A. Beller; Mohamed Amine Gharbi

arXiv · 2306.01118

Templated self-assembly of gold nanoparticles in smectic liquid crystals confined at 3D printed curved surfaces

Mackenzie O'Keefe·Jane Bernadette Denise M. Garcia·Abeco J. Rwakabuba·Timothy M. Otchy·Daniel A. Beller·Mohamed Amine Gharbi

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Abstract

The fabrication of assembled structures of topological defects in liquid crystals (LCs) has attracted much attention during the last decade, stemming from the potential application of these defects in modern technologies. A range of techniques can be employed to create large areas of engineered defects in LCs, including mechanical shearing, chemical surface treatment, external fields, or geometric confinement. The technology of 3D printing has recently emerged as a powerful method to fabricate novel patterning topographies inaccessible by other microfabrication techniques, especially confining geometries with curved topographies. In this work, we show the advantages of using 3D-printed curved surfaces and controlled anchoring properties to confine LCs and engineer new structures of topological defects, whose structure we elucidate by comparison with a novel application of Landau-de Gennes free energy minimization to the smectic A-nematic phase transition. We also demonstrate the ability of these defects to act as a scaffold for assembling gold (Au) nanoparticles (NPs) into reconfigurable 3D structures. We discuss the characteristics of this templated self-assembly (TSA) approach and explain the relationship between NP concentrations and defect structures with insights gained from numerical modeling. This work paves the way for a versatile platform of LC defect-templated assembly of a range of functional nanomaterials useful in the field of energy technology.

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Mackenzie O'Keefe, Jane Bernadette Denise M. Garcia, Abeco J. Rwakabuba, Timothy M. Otchy, Daniel A. Beller, Mohamed Amine Gharbi. 2023-06-01. Templated self-assembly of gold nanoparticles in smectic liquid crystals confined at 3D printed curved surfaces. https://arxiv.org/abs/2306.01118

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