The synthesis of well-defined nanocarbon multilayers, beyond the bilayer structure, is still a challenging goal. Herein, two trilayer nanographenes were synthesized by covalently linking nanographene layers through helicene bridges. The structural characterization of the trilayer nanographenes revealed a compact trilayer-stacked architecture. The introduction of a furan ring into the helicene linker modulates the interlayer overlap and π-conjugation of the trilayer nanographenes, enabling the tuning of the interlayer coupling, as demonstrated by optical, electrochemical, and theoretical analyses. Both synthesized trilayer nanographenes are rigid chiral nanocarbons and show a chirality transfer from the helicene moiety to the stacked nanographene layers. These helical trilayer nanographenes reported here represent the covalently linked multilayer nanographenes rather than bilayer ones, showing the tunable multilayer stacking structure.

Nanographenes are inclined to assemble into stacked columnar structures that are stabilized by π‐π interactions, whereas other supramolecular structures of nanographenes, such as prisms and cages, are rarely investigated. Herein, a diazananographene was synthesized, and then assembled with a coordination unit, thereby producing a triangular metallaprism. After adding C60 or C70, the triangular metallaprism was transformed into a square tetramer, which encapsulated a pair of C60 or C70 molecules. The formed host‐guest complex demonstrated efficient energy transfer from the diazananographene shell to the C60 cores. The emission intensity of the capsulated C60 was enhanced remarkably, compared with free C60, due to an increased quantum yield and optical absorption coefficient. This work demonstrates the versatility of nanographene‐based supramolecular architectures beyond columnar stacking and their ability to enhance the emission of otherwise non‐emissive fullerene.

Nanographenes are inclined to assemble into stacked columnar structures that are stabilized by π‐π interactions, whereas other supramolecular structures of nanographenes, such as prisms and cages, are rarely investigated. Herein, a diazananographene was synthesized, and then assembled with a coordination unit, thereby producing a triangular metallaprism. After adding C60 or C70, the triangular metallaprism was transformed into a square tetramer, which encapsulated a pair of C60 or C70 molecules. The formed host‐guest complex demonstrated efficient energy transfer from the diazananographene shell to the C60 cores. The emission intensity of the capsulated C60 was enhanced remarkably, compared with free C60, due to an increased quantum yield and optical absorption coefficient. This work demonstrates the versatility of nanographene‐based supramolecular architectures beyond columnar stacking and their ability to enhance the emission of otherwise non‐emissive fullerene.