Controlled Hierarchical Self-Assembly of Nanoparticles and Chiral Molecules into Tubular Nanocomposites

J Am Chem Soc. 2023 Apr 6. doi: 10.1021/jacs.3c00636. Online ahead of print.

Abstract

In this work, we show how the kinetics of molecular self-assembly can be coupled with the kinetics of the colloidal self-assembly of inorganic nanoparticles, which in turn drives the formation of several distinct hierarchically assembled tubular nanocomposites with lengths over tens of micrometers. These colloidal nanoparticles primarily serve as "artificial histones," around which the as-assembled supramolecular fibrils are wound into deeply kinetically trapped single-layered nanotubes, which leads to the formation of tubular nanocomposites that are resistant to supramolecular transformation thermally. Alternatively, when these nanoparticles are aggregated prior to the event of molecular self-assembly, these as-formed nanoparticle "oligomers" would be encapsulated into the thermodynamically favored double-layer supramolecular nanotubes, which enables the non-close-packing of nanoparticles inside the nanotubes and results in the nanoparticle superlattices with an open channel. Furthermore, increasing the amounts of nanoparticles enables the assembly of nanoparticles into pseudohexagonal superlattices at the external surface in a sequential fashion, which ultimately drives the formation of triple-layered hierarchically assembled tubular nanocomposites. Importantly, the sense of helicity transfers from the supramolecular nanotubes to the pseudo nanoparticle superlattices with a chiral vector of (2, 9). Our findings represent a strategy for controlling the hierarchical assembly bridging supramolecular chemistry to the inorganic solids to realize the complexity by design.