This invention relates to a method for exfoliating inorganic layered compounds to form two- dimensional (2D) inorganic compounds. The exfoliation is carried out in aqueous media in the present of polycyclic aromatic compounds. The invention also relates to aqueous suspensions of two-dimensional compounds which arise from the exfoliation method. The invention further relates to methods of forming thin films of two-dimensional compounds from suspensions and to devices comprising thin films of two-dimensional (2D) inorganic compounds.