Directed Noncovalent Synthesis of Dendritic Spherulitic Superstructures via Surface-Mediated Secondary Nucleation

Constructing complex functional supramolecular architectures from simple molecular building blocks is a central challenge in supramolecular chemistry. Unlike classical primary nucleation-elongation mechanisms, secondary nucleation has emerged as a promising route to construct advanced supramolecular polymers. In this study, we demonstrate the formation of 3D dendritic spherulitic superstructures (DSS) through the surface-assisted secondary nucleation-driven self-assembly of chiral perylenemonoimide dyes. Comprehensive morphological investigations reveal a well-defined hierarchical organization, culminating in the emergence of homochiral spherulites with radii reaching approximately 50 µm. Time-dependent morphological and spectroscopic investigations reveal a progressive transition from helical fibers to complex superhelical and ultimately dendritic spherulitic morphologies. Strikingly, these chiral DSS exhibit strong chiroptical properties, generating pronounced photocurrent responses under circularly polarized light, with enhanced responsivity and an average 0.33 dissymmetry factor. This work provides detailed insight into supramolecular polymerization via secondary nucleation and establishes a design principle for dynamic chiral materials with potential chiroptical sensing applications and optoelectronic devices.