Impact on bulk and interfacial dielectric properties of nematic liquid crystals due to silver nanoparticles

Abstract

Doping of nanomaterials into the liquid crystals (LC) can greatly enhance the physical properties of host LC. Since, it is not possible to obtain all the desired parameters of a display device in a single LC, several researchers are trying to optimize the display parameters by using different nanomaterials of different functionalization. In this work, we report the effect of hexane thiol functionalised silver nanoparticles (f-AgNPs) on the dielectric relaxation and electrical properties of nematic liquid crystal 4-trans-pentyal-cyclohexyl cyanobenzene (5PCH) in the homeotropic alignment. The impedance spectroscopy response of pure and f-AgNPs doped nanocomposites of 5PCH are studied in the frequency range of 20Hz - 12MHz. The electrical properties such as bulk capacitance, electrode resistance, double layer capacitance, bulk resistance and Warburg diffusion coefficients were determined by fitting a suitable equivalent electrical circuit model to the experimental data. Temperature dependence of the dielectric relaxation frequency for pure and f-AgNPs doped nanocomposites of 5PCH were also investigated.