A Two‐Dimensional Polyimide‐Graphene Heterostructure with Ultra‐fast Interlayer Charge Transfer

Two-dimensional polymers (2DPs) are a class of atomically/molecularly thin crystalline organic 2D materials. They intriguing candidates for the development unprecedented organic–inorganic van der Waals heterostructures (vdWHs) with exotic physicochemical properties. In this work, we demonstrate on-water surface synthesis large-area (cm2), monolayer polyimide (2DPI) 3.1-nm lattice. Such 2DPI comprises metal-free porphyrin and perylene units linked by imide bonds. We further achieve scalable 2DPI-graphene (2DPI-G) vdWHs via face-to-face co-assembly graphene on water surface. Remarkably, femtosecond transient absorption spectroscopy reveals an ultra-fast interlayer charge transfer (ca. 60 fs) in resultant 2DPI-G vdWH upon protonation acid, which is equivalent to that fastest reports among inorganic vdWHs. large electronic coupling ascribed cation–π interaction between 2DP graphene.