CPL-active supramolecular polymers

Abstract

Supramolecular polymers constitute a highly dynamic and rapidly evolving research field, characterized by the continuous development of systems with increasing structural and functional complexity. Theoretical and mathematical models aimed at understanding the mechanisms of supramolecular polymer formation have played a crucial role in guiding the design of these systems, enabling the discovery of novel assembly pathways and emergent functionalities in both self- and co-assembled architectures. Within this broad landscape, chiral supramolecular polymers occupy a particularly prominent position, as they provide an effective platform for generating well-defined helical structures that can serve as models for the emergence of homochirality in nature, while simultaneously enabling a wide range of advanced functional properties. Of particular interest is the incorporation of emissive moieties into the monomeric building blocks of chiral supramolecular polymers, which can lead to the formation of emissive aggregated species exhibiting circularly polarized luminescence (CPL). The CPL activity of these systems significantly enhances their relevance across multiple research areas, extending their impact beyond fundamental supramolecular chemistry to applied materials science. This review focuses on representative examples of the diverse strategies employed to obtain CPL-active supramolecular polymers, including the introduction of chiral elements—such as point or axial chirality—into monomeric units, as well as the integration of metallic components. Furthermore, the collected examples demonstrate the high responsiveness of CPL-active supramolecular polymers to external stimuli such as light, solvent polarity and temperature, highlighting their exceptional versatility. These adaptive properties enable the realization of systems with notably high dissymmetry factors (g_lum) and circularly polarized luminescence brightness (B_CPL). Finally, the review presents both metallo-organic and purely organic CPL-active supramolecular polymers, together with selected examples of their outstanding applications in areas such as optoelectronic devices, anticounterfeiting technologies, and information encryption.