Effects of morphology and concentration of CuS nanoparticles on alignment and electro-optic properties of nematic liquid crystal

摘要

Nanopartides (NPs) with flower-like and frame morphologies were synthesized from CuS,a remarkable transition-metal sulfide.We introduced two kinds of CuS NPs into a nematic liquid crystal (LC) 4-cyano-4'-n-pentylbiphenyl (5CB) and investigated the morphology-and concentration-dependent alignment and electro-optic (E-O) effects of CuS NPs on 5CB.A trace amount of flower-like CuS NPs induced a uniform homeotropic orientation of LC molecules;this is attributable to the obtained desirable compact nanosheet structure.Moreover,both flower-like and frame CuS NPs induced a remarkable improvement in the E-O properties of 5CB,and the flower-like CuS/5CB system exhibited a better performance.The doped CuS NPs in the LC host suppressed the shielding effect and strengthened the electric field,resulting in outstanding E-O properties.At a doping concentration of 0.05 wt.％,CuS NPs were well-dispersed and achieved the optimum E-O performance.This study provides a novel method for inducing a uniform orientation and enhanced E-O properties of LC molecules by doping with extraordinary CuS NPs,leading to potential applications in establishing flexible LC displays.