Improvement in alignment of gold nanorod/ferroelectric liquid crystal composites by reduction in ion impurities

At present, LCDs have completely replaced conventional cathode ray tube (CRT) displays. LCDs offer the advantage of being significantly thinner and lighter, making them highly portable. With advancements in fabrication technology, LCDs have become cost-effective alternatives to CRTs. Over recent decades, extensive research by various groups has focused on liquid crystal (LC)-based nanoparticle (NP) composite materials, a prominent area in LCD-related studies. Research on LC-NP composites allows the exploration of synergistic combinations of LCs and NPs, each contributing unique characteristics. By doping NPs with LCs, properties such as localized surface plasmon resonance (SPR) of metal nanoparticles (MNPs) like Ag, Au, and Pt can be tailored. LCs play a crucial role in modifying NP assembly, thereby influencing the morphological organization of NPs and their remarkable electro-optical and electronic properties, essential for nanoscale device fabrication. Conversely, NPs can also tune the characteristics of LCs, including their EO properties and alignment in display technologies.

This study explores how adding gold nanorods (GNRs) to ferroelectric liquid crystal (FLC) devices affects their properties. GNR concentrations from 0.025 wt.% to 0.1 wt.% were tested. Adding GNRs at 0.025 wt.% and 0.050 wt.% improved optical contrast, tilt angle, absorbance, and photoluminescence intensity. The alignment of FLC composites with GNRs was better, with fewer light leakage centers. Also, the relative permittivity, dielectric loss, and DC conductivity improved with GNR inclusion. This suggests that GNRs can enhance the performance and efficiency of FLC devices.