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With high surface area and novel properties, 2D materials are potentially useful for a range of applications. In addition to graphene, many 2D compounds exist with BN, MoS 2, and Bi 2Te 3, generating renewed interest. Such materials are found stacked in layered crystals and can be metals, semiconductors, or insulators.[1] In addition, some are thermoelectric materials,[2] superconductors,[3] or topological insulators.[4] In order to unlock these valuable properties, these materials must be easily exfoliated to thin layers. Here we show a simple, large-scale method to exfoliate BN, transition metal dichalcogenides, and transition metal oxides down to very thin platelets in water. The platelets are stabilized against reaggregation by a surfactant coating. Liquid-phase exfoliation allows the formation of films and the production of hybrids and composites. For example, hybrid nanotube–MoS 2 films show promise for thermoelectric and battery applications, while NbSe 2 films show potential as transparent conductors.

In addition to graphite, a wide range of inorganic layered compounds exist. A good example is the family of transition metal dichalcogenides (TMDs).[1] These form 2D layers of covalently bonded transition metal atoms, M, and chalcogen atoms, X (X= S, Se, Te), in the stoichiometry MX 2, with examples such as MoS 2, NbSe 2, and NiTe 2.[1] In addition, some transition metal oxides [5] form 2D structures, as do other materials such as BN, Bi 2Te 3, Sb 2Se 3, FeTe, etc. In general these 2D layers tend to bond via van der Waals interactions, stacking to form 3D crystals. These materials span the whole range of electronic structures from insulator to …