The composition of a self-assembly system has long been an essential factor that governs the resulting supramolecular structures. Nevertheless, due to the rigorous demands of structural compatibility in host–guest chemistry, the molar ratio of host–guest mixtures has not been applied as a significant factor in modulating the supramolecular structures of host–guest complexes. In this study, via using a novel unimolecular quaternary clip (Q-clip) as the host molecule and pyrene as the guest molecule and a nanotemplating reagent, we discovered that the changes in the molar ratios of the Q-clip:pyrene mixtures resulted in the structural modulation of the host–guest complexes. Supramolecular lamellae made by the 1:4 Q-clip:pyrene mixture and a hexagonal columnar phase (Colh) made by the 1:8 Q-clip:pyrene mixture were identified by the 1D powder and 2D fiber WAXS characterizations. Time-resolved synchrotron X-ray characterization and thermal analysis further showed that removing the easily sublimed guest molecules (pyrene) via thermal annealing simply hollowed out the supramolecular structures without damaging the supramolecular scaffolds made by the Q-clips. Pyrene is thus a nanotemplating reagent that can be used to create the hollowed-out 2D lamellar and 1D cylindrical scaffolds of Q-clips. The study thus gave a novel example of a host–guest mixture that is able to carry out composition-driven structural modulation and guest-induced nanotemplates. The finding broadens the horizon of host–guest chemistry and may inspire more nanoinnovation.

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The shapeshifting behavior for synthetic matters was found at either the molecular or supramolecular level, but the connection between shapeshifting at the two hierarchical levels remains missing. In this study, an 8-arm star giant molecule, NPOSS, was synthesized to connect the molecular and supramolecular shapeshifting. Controlling the conditions of bulk self-assembly allowed us to bring NPOSS into three different Ostwald’s stages of nucleation. The high conformational flexibility of NPOSS facilitates molecular shapeshifting and allows NPOSS to take the discotic, rod-like and star-like geometries in different Ostwald’s stages. Simultaneous changes in the supramolecular scaffolds were observed as the discotic, rod-like and star-like NPOSS molecules self-assembled into the supramolecular scaffolds of 1D columns, 2D lamellae, and 3D networks, respectively. These changes in the hierarchical structures also affect the CO2 affinity of NPOSS. Therefore, the connection between the molecular/supramolecular shapeshifting and the structure-driven property changes of NPOSS were established by taking advantage of the high conformational freedom of the 8-arm star giant molecule and its diverse self-assembly pathways leading to the different Ostwald’s stages.