Fast growth of monolayer organic 2D crystals and their application in organic transistors

Abstract Growth of monolayer 2D organic crystal has been an interesting topic in recent years owing to their promising properties. However, it is still a tough challenge to obtain the 2D organic crystal with precise thickness control and uniform morphology. Herein, we reported the fabrication of 2D crystals of alkane molecules C 44 H 90 with only monolayer thickness and tunable size through the simple dip-coating process. Benefitted from the low solubility of the C 44 H 90 and the isotropic Van der Waals interaction, quadrilateral-shape monolayer 2D crystals with size from several micrometers to nearly hundreds of micrometers can be achieved in the dip-coating process. Utilized the X-ray diffraction and high resolution atomic force microscopy, we obtained the clear packing mode of these monolayer crystals. In addition, these smooth 2D crystals show promising application in the thin film transistors by acting as a molecular template layer. It leads to an increment of about one magnitude on the charge mobility owing to the decreasing of both morphology defects and interface traps.