Organic circularly polarized luminescence materials in various aggregation states

Abstract

Circularly polarized luminescence (CPL) materials have attracted extensive research attention in recent years. Owing to their multidimensional optical information transmission capability, an increasing number of CPL-active materials with enormous practical potential—including small molecules, aggregates, and other forms—have been applied in various optoelectronic display fields. Among these, organic CPL materials, characterized by lower energy loss and easier designability, stand out particularly. However, the CPL properties of organic small molecules with different structures often exhibit significant variations in varying aggregation states, which stems from their intrinsic complex excited-state dynamic mechanisms. This review starts from several typical small-molecule designs, categorizing them based on well-established construction strategies from predecessors, and introduces the research reported in recent years on the performance, regulation, and intrinsic mechanisms of CPL materials in aggregation states such as crystals, supramolecular assemblies, and polymers synthesized using different strategies. It aims to outline the current main research focuses and design concepts in the related field. Finally, we briefly analyse the challenges faced by and opportunities in organic aggregated-state CPL materials.