Strategies for designing luminescent metallo-supramolecular polymer networks

Abstract

Nature offers numerous examples of materials with extraordinary and multifaceted properties, like combined self-healing, stimuli-responsiveness, and luminescence. Inspired by such designs, chemists have tried to mimic such versatile properties by combining complex polymeric structures reinforced by supramolecular interactions, allowing them to perform multiple functions across various time and length scales. Among these efforts, metal coordination has emerged as a powerful tool to create dynamic, tunable systems. This review explores such innovative approaches in designing luminescent metallo-supramolecular polymer networks (MSPNs), which integrate the entanglement of polymer chains with the dynamic luminescent properties of metal–ligand junctions. Classified by the dimensionality of these junctions, from 0D, formed by single metal ion complexes, to 2D metallacycles, and 3D metallacages, MSPNs benefit from diverse functionalities of junctions, featuring the antenna effect in lanthanide-based 0D nodes and aggregation-induced emission (AIE) in 2D and 3D assemblies, on top of organic conjugated structures that can be integrated in the ligand structure. This initiative addresses the fragile nature and limited formability as one of the main classical barriers to commercialize supramolecular coordination complexes (SCCs) for real-life applications. Since developing such polymeric products requires studying material properties on a new range of time and length scales that are less frequently used by classical chemists, there is gap of knowledge that hinders development of such hybrid materials. By exploring the design strategies of this emerging class of materials, and highlighting macromolecular characteristics of such networks, this review seeks to encourage the development of further luminescent networks based on polymeric constitutes, unlocking new possibilities for applications in advanced functional materials.