Liquid-phase exfoliation of ultrathin layered transition metal dichalcogenide nanosheets composed of solid-solution Mo1-xWxS2

Transition metal dichalcogenide (TMD) nanosheets have attracted attention as novel inorganic materials. Aiming to enhance their availability, we targeted the large-scale synthesis of TMD solid-solution nanosheets by liquid-phase exfoliation. To prepare the nanosheets, bulk polycrystalline Mo1-xWxS2 was sonicated in dimethyl sulfoxide. Transmission electron microscopy and atomic force microscopy showed that few-layer nanosheets were formed. UV-VIS spectroscopy showed that the band structure could be continuously tuned. Compared with mechanical cleaving, our exfoliation method facilitates larger-scale production of nanosheets and should be useful for a wide range of applications, such as thin films and composite materials. (copyright 2014 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)