Light-Responsive Supramolecular Nanotubes-Based Chiral Plasmonic Assemblies

ACS Nano. 2023 Mar 28;17(6):5548-5560. doi: 10.1021/acsnano.2c10955. Epub 2023 Mar 10.

Abstract

We describe the fabrication of dual-responsive (thermo/light) chiral plasmonic films. The idea is based on using photoswitchable achiral liquid crystal (LCs) forming chiral nanotubes for templating helical assemblies of Au NPs. Circular dichroism spectroscopy (CD) confirms chiroptical properties coming from the arrangement of organic and inorganic components, with up to 0.2 dissymmetry factor (g-factor). Upon exposure to UV light, organic molecules isomerize, resulting in controlled melting of organic nanotubes and/or inorganic nanohelices. The process can be reversed using visible light and further modified by varying the temperature, offering a control of chiroptical response of the composite material. These properties can play a key role in the future development of chiral plasmonics, metamaterials, and optoelectronic devices.

Keywords: liquid crystals; nanocomposites; organic nanotubes; photoswitchability; plasmonic nanoparticles; reversibly reconfigurable assembly; supramolecular self-assembly.