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 C₄₄H₉₀ with only monolayer thickness and tunable size through the simple dip-coating process. Benefitted from the low solubility of the C₄₄H₉₀ 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.

由于其有希望的性质，近年来单层二维有机晶体的生长已成为一个有趣的话题。然而，获得具有精确的厚度控制和均匀的形态的二维有机晶体仍然是一个艰巨的挑战。本文中，我们报道了通过简单的浸涂工艺仅具有单层厚度和可调尺寸的烷烃分子C ₄₄ H ₉₀的二维晶体的制造。受益于C ₄₄ H ₉₀的低溶解度通过各向同性的范德华相互作用，可以在浸涂过程中获得尺寸从几微米到几百微米的四边形单层二维晶体。利用X射线衍射和高分辨率原子力显微镜，我们获得了这些单层晶体的清晰堆积模式。另外，这些光滑的2D晶体通过充当分子模板层，显示出在薄膜晶体管中的应用前景。由于形态缺陷和界面陷阱的减少，导致电荷迁移率增加约一个量级。