The influence of graphene nanoplatelets on the Freedericksz transition threshold in nematic liquid crystals

摘要

The paper is concentrated on the study of basic properties of a nematic liquid crystal mixture with graphene nanoplatelets (GP). This analysis might provide valuable information about the anchoring forces of molecules on graphene surface and the possibility to control the alignment angle by GP concentration and the applied voltage. Freedericksz transition threshold was determined from the voltage dependence of the light intensity through the sample placed between crossed polarizers. The results indicated a decrease of the critical voltage when low amounts of graphene was added into the mixture (0.2%). For higher graphene concentration (0.9%), a different behavior of the mixture is observed suggesting a nanoplatelets clustering.