On-water surface synthesis of electronically coupled 2D polyimide-MoS2 van der Waals heterostructure

The water surface provides a highly effective platform for the synthesis of two-dimensional polymers (2DP). In this study, we present an efficient on-water surface synthesis of crystalline monolayer 2D polyimide (2DPI) through the imidization reaction between tetra (4-aminophenyl) porphyrin (M1) and perylenetracarboxylic dianhydride (M2), resulting in excellent stability and coverage over a large area (tens of cm(2)). We further fabricate innovative organic-inorganic hybrid van der Waals heterostructures (vdWHs) by combining with exfoliated few-layer molybdenum sulfide (MoS2). High-resolution transmission electron microscopy (HRTEM) reveals face-to-face stacking between MoS2 and 2DPI within the vdWH. This stacking configuration facilitates remarkable charge transfer and noticeable n-type doping effects from monolayer 2DPI to MoS2, as corroborated by Raman spectroscopy, photoluminescence measurements, and field-effect transistor (FET) characterizations. Notably, the 2DPI-MoS2 vdWH exhibits an impressive electron mobility of 50 cm(2)/Vs, signifying a substantial improvement over pristine MoS2 (8 cm(2)/Vs). This study unveils the immense potential of integrating 2D polymers to enhance semiconductor device functionality through tailored vdWHs, thereby opening up exciting new avenues for exploring unique interfacial physical phenomena.

Automated summary

This study demonstrates an efficient on-water surface synthesis of crystalline monolayer 2D polyimide (2DPI) with excellent stability and coverage. By combining with exfoliated MoS2, innovative organic-inorganic hybrid van der Waals heterostructures (vdWHs) are fabricated, facilitating remarkable charge transfer and improved electron mobility.