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

We report on the phase behavior and dielectric properties of the liquid crystal (LC) 4'-n-octyloxy-4-cyanobiphenyl dispersed with graphene nanoplatelets (GNPs). The temperature-dependent dielectric permittivity at 10(4) Hz and its derivative with respect to the temperature reveal that the incorporation of GNPs in a LC cell leads to the modification of crystalline polymorphism and shift in phase transition temperature owing to the enhanced positional and orientational order. Additionally, the dielectric data between 1 and 10(3) Hz show that the dopant reduces the ionic concentration and alters the diffusivity in the LC mesophases. (C) 2013 AIP Publishing LLC [http://dx.doi.org/10.1063/1.4802839]