  The vertical integration of multiple two-dimensional (2D) materials in
heterostructures, held together by van der Waals forces, has opened
unprecedented possibilities for modifying the (opto-)electronic properties of
nanodevices. Graphene, with its remarkable opto-electronic properties, is an
ideal candidate for such applications. Further candidates are 2D polymers,
crystalline polymeric materials with customizable structure and electronic
properties that can be synthesized in all mathematically possible Bravais
lattices. In this study, we investigated the optoelectronic properties of a
heterostructure created by pristine graphene and a rectangular 2D polyimide
(2DPI) film. This imprints a new superlattice on graphene in conjunction with a
direct influence on its electronic properties. Theoretical and experimental
analyses reveal that interlayer charge exchange between the 2D polymer and
graphene induces hole doping in the graphene layer. We have also observed that
the properties of the heterostructure are dependent on the substrate used in
experiments, likely due to the porous character of the 2DPI allowing direct
interaction of graphene with the support. These findings highlight the unique
ability to tailor functionalities in 2D polymers-based heterostructures,
allowing the development of optoelectronic devices with precisely engineered
properties and stimulating further exploration of the diverse phenomena
accessible through tailored designs of the 2D polymers.
