Conjugated polymer architectures with highly improved affinity to specific single-walled carbon nanotubes

Conjugated polymers are used to sort polychiral mixtures of single-walled carbon nanotubes (SWCNTs), generating highly valuable materials of precisely defined optical and electrical characteristics. However, the underlying interactions between these components are not understood to a sufficient extent, so to harvest a specific SWCNT chirality, a trial-and-error approach is usually utilized, which necessitates the use of a broad spectrum of conjugated polymers. Despite the labor- and cost-intensive nature of such a tactic, its success is still uncertain. In this study, we examined the interplay of a variety of synthesized conjugated polymers with SWCNTs to get a fundamental understanding of their modus operandi. We discovered that heteroatoms embedded in the polymers substantially enhanced the binding strength of the polymer molecules to SWCNTs. The performed multiscale calculations revealed that the presence of such elements increased the interaction between the polymer molecules and SWCNTs. Interestingly, the conjugated polymers exhibited a bifurcation phenomenon when free of heteroatoms. The robustness of the polymer/SWCNT hybrid hinged upon its assuming a particular initial orientation in space. Our findings provide insight into the design of polymers capable of strong and selective binding with specific types of SWCNTs in a reproducible manner. This insight is supposed to facilitate the long-awaited implementation of monochiral SWCNTs in a broad spectrum of applications.