Fabrication of 2D Crystals by Intercalation of a Bulk ZnWO4 Single Crystals

In the present paper, we describe a method for obtaining two-dimensional dielectric crystal from bulk ZnWO4 single crystals. The method includes a combination of intercalation and an ultrasonic treatment of a suspension of ZnWO4 single crystals. For the first time, ZnWO4 crystals down to 1.5 nm thick were obtained. The intercalation is shown to proceed predominantly through vertical defects in the crystal. The shape of the microcrystals obtained exhibits a pronounced faceting typical of single-crystal ZnWO4 fragments. The technique proposed makes it possible to exfoliate monolayer crystals. The results of the present study can prove useful for creation of new free-standing two-dimensional film heterostructures. The obtained suspension of dielectric two-dimensional crystals is promising in two-dimensional printing for flexible electronics.