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Updated: Jun 13, 2025

An Electrochemical Cholesteric Liquid Crystalline Device for Quick and Low-Voltage Color Modulation
Published on: February 27, 2019
Sign Inversion of Circularly Polarized Luminescence in Cholesteric Liquid Crystals Induced by Mercury Ions through
Lulu Li1, Peiting Jiang1, Xueyan Zhang2
1School of Environmental and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang, 212003, China.
Abstract:
Stimuli-responsive circularly polarized luminescence (CPL) materials based on cholesteric liquid crystal (CLC) platforms show great promise for applications in information encryption and anticounterfeiting. In this study, we constructed a mercury ion-responsive CPL system in CLCs by controlling the conjugation degree of axially chiral binaphthyl derivatives. Two chiral binaphthyl derivatives (R/S-1 and R/S-2) were initially used as chiral dopants to demonstrate that CPL inversion (glum values from 0.5/-0.44 to -0.53/0.48) in CLCs could be achieved by modulating the conjugation degree of the chiral binaphthyls. Based on this concept, the thioacetal binaphthyl R-2S was developed and used as a mercury-responsive chiral dopant in CLCs. Under Hg ion treatment, the CPL sign inverted (glum value changed from 0.22 to -0.29) due to the transformation of the thioacetal into an aldehyde group. Additionally, the mercury ion-responsive CPL material was applied in information encryption.
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