Ionic properties of liquid crystals dispersed with carbon nanotubes and montmorillonite nanoplatelets

Abstract

The ionic properties of liquid crystals doped with one-dimensional carbon nanotubes, two-dimensional montmorillonite, and a mixture of both are investigated. The results indicate that the relaxation times of electrode polarization and ionic conductivity are time-dependent after the cell fabrication regardless of doping. While all of the dopants are effective in capturing impurity ions, the cells containing the hybrid dopant exhibit the feeblest ionic effect at room temperature.

Phase and dielectric behaviors of a polymorphic liquid crystal doped with graphene nanoplatelets

“…1,2 Moreover, investigations demonstrating the suppressed ionic effect by nanodopants have also been clarified for solving image problems in LC displays caused by ubiquitous impurity ions. [3][4][5][6][7] Depending on the intrinsic characteristics of the dopant and mutual interaction with LC molecules, researchers have studied the individual effects of nanomaterial additives on the behaviors of phase transitions in LCs in terms of the molecular ordering, 8,9 dielectric relaxation, 10 and electrophysical properties of LCs. [11][12][13] Among currently available nanomaterials, graphene, classified as a two-dimensional (2-D) carbon allotrope, has attracted immense attention for potential applications in electronic devices and nanocomposites since its successful isolation in 2004.…”

Nano-Objects and Ions in Liquid Crystals: Ion Trapping Effect and Related Phenomena

“…It was also observed that the efficiency to trap ions by nano-clay was varying in time [213]. More efficient ion trapping in liquid crystals can be achieved by combining low concentrations of nano-clay with comparable amounts of carbon nanotubes [214]. Higher concentrations of montmorillonite in nematic liquid crystals (up to 5 wt.…”

“…Conducting nanofiber NLC Increase in the conductivity [208,209] Polymeric nanoparticles FLC Decrease in dielectric losses [210] Nanoclay (montmorillonite) NLC Ion trapping, time dependent properties, and aggregation [211][212][213][214][215][216][217] x x S ZnO …”

“…Very interesting electrical behavior was found in liquid crystal systems doped with montmorillonite platelets [211][212][213][214][215][216][217]. Montmorillonite is a type of smectic clays characterized by a sandwich "tetrahedral-octahedral-tetrahedral" structure made of aluminosilicate lamellar materials.…”

Investigation of liquid crystal dispersion and dielectric relaxation behavior in polymer dispersed liquid crystal composite films

“…Liu and W. Lee have studied temperature dependent dielectric properties of MMT and CNT doped nematic LC E7. They have concluded that, dopant does not influence the intrinsic identity of LC host in terms of dielectric dispersion till the clearing temperature of nematic LC [30]. But at the higher temperature, thermal agitation becomes more predominant as compared to intermolecular interaction which produces randomization of dipoles [17,31].…”