Secondary nucleation guided noncovalent synthesis of dendritic homochiral superstructures via growth on and from surface.

Secondary nucleation is an emerging approach for synthesizing higher-order supramolecular polymers with exciting topologies. However, a detailed understanding of growth processes and the synthesis of homochiral superstructures is yet to be demonstrated. Here, we report the non-covalent synthesis of dendritic homochiral superstructures using NIR triimide dyes as building blocks via a secondary nucleation elongation process. Detailed analysis of kinetics and temporal evolution of morphology indicates that the formation of dendritic homochiral superstructures proceeds via growth on the surface and growth from the surface of the seeds. The combination of these two processes leads to the formation of elegant homochiral superstructures with a size of ~0.4 mm, having a superhelix at the center and helical fibres as branches. Moreover, these dendritic homochiral superstructures exhibit significantly high chiro-optical photoresponse with the magnitude of g reaching a value as high as 0.55 - 0.6. Thus, our results provide insights into the growth process of homochiral superstructures with dendritic topology, which can be critically important for the design and optimization of chiral-selective optoelectronic devices leveraging controlled self-assembly.