Graphene solution is an aqueous, homogeneous, black liquid with a graphene concentration . Graphene solution is prepared by bath sonication of natural graphite flakes in ethanol/water mixtures. Due to its hydrophobic nature, the preparation of a stable and highly concentrated graphene solution without surfactants or dispersants is a challenging task. Graphene was dispersed in aqueous solutions using different surfactants. Graphene solution is coated onto insulating substrates to form conductive films.