Noncovalent synthesis of higher-order super-heterostructures from structurally distinct molecular π-systems via secondary nucleation

Noncovalently connecting supramolecular assemblies of structurally distinct π-systems to result in higher-order heterostructures is a grand challenge due to the problem of phase segregation into individual components. Although a few supramolecular heterostructures were recently reported, they are based on molecular π-systems with minimal structural differences. In this study, we demonstrate a rational approach to construct fully supramolecular bicomponent higher-order super-heterostructures such as fibers-reinforced two-dimensional nanoplatelet clusters using structurally distinct π-systems. We have achieved this using near-infrared absorbing tetraimide dye and perylene diimide as the building blocks. Here, perylene diimide acts as a source of dormant monomers, and the self-assembled structures of the tetraimide dye serve as the seeds. Interestingly, tetraimide dye self-assemble into two-dimensional nanoplatelet clusters with switchable hierarchy in dimethyl sulfoxide. When the dormant monomers of perylene diimide are added to the tetraimide seeds, nucleation occurs on the surface of the two-dimensional nanoplatelets of the clusters, and their switchable hierarchy allowed us to synthesize two types of corresponding super-heterostructures selectively. Our investigations further reveal that secondary nucleation and dispersive interactions guide the formation of these super-heterostructures. Non-covalently connecting supramolecular assemblies of structurally distinct π-systems which yield higher-order heterostructures are challenging due to phase segregation into individual components. Here, the authors demonstrate a rational approach to construct fully supramolecular bicomponent higher-order super-heterostructures using structurally distinct π-systems.