Preparation and characterisation of graphene-based lyotropic liquid crystals.

Abstract

Since graphene was discovered, interest on this material has been on the rise for the last few years. This is due to its extraordinary properties and its wide variety of applications. On the other hand, another result of interest for research purposes is the possibility to form lyotropic liquid crystals with dispersed micro or nanoscale objects by self-assembling processes. Combining the above items and taking into account their current relevance, the preparation of graphene oxide lyotropic liquid crystals by dispersing graphene oxide flakes in water is presented as an option with potentially high relevance. In this project, we have prepared graphene oxide liquid crystals by following different protocols reported by some research groups. Characterisation by polarizing optical microscopy has allowed us to observe the formation of textures reminiscent to those observed in standard liquid crystals, both at interfacial regions or around inclusions. Moreover, we were able to detect that graphene oxide dispersions undergo phase separation with time, resulting in a birefringent phase and an isotropic phase. Finally, we have explored