Highly Confined Phases of Graphene Oxide Sheets

The graphene oxide (GO) is widely used as a graphene precursor. It has been recently evidenced that this object can form different lyotropic liquid crystals phases observed in highly anisotropic colloids. The confinement of GO sheets, a two-dimensional (2D) crystal is herein aim of study. The binary GO water is studied to describe the liquid crystallinity of concentrated dispersions, characterized through complementary techniques as X-ray Scattering and Polarized Optical Microscopy. Concentrated GO dispersions were achieved by implementing rigorous procedures, based on high rate centrifugation (where concentrations between 15 and 20 % (mass) were achieved) followed by dehydration (dispersions up to 100 % were characterized), avoiding the formation of aggregates. Some phase transitions were detected in concentrated domains, never studied before. The Dynamic Light Scattering was used to characterize the GO sheets dimensions.