Circularly polarized luminescence from assembled nanoscale particles

Circularly polarized luminescence (CPL) from assembled nanoscale materials presents a rapidly advancing field with significant implications for optoelectronics, bioimaging, and chiral photonics. The ability to engineer CPL-active systems through the controlled assembly of nanoscale particles offers a versatile platform for tuning chiroptical properties beyond what is possible with individual components. This review provides a comprehensive overview of design strategies for achieving efficient CPL emission from nanoscale particles and their assemblies. We systematically differentiate between the design approach and the specific nanoscale entities employed, analyzing the benefits and limitations associated with each. A particular emphasis is placed on hierarchical chiral structures capable of exhibiting CPL activity, whether constructed from inherently chiral or achiral building blocks. For assemblies composed of achiral components, we delve into the physicochemical mechanisms underlying their emergent chirality and CPL behavior. In the final part of the review, we highlight recent advances and future prospects in the field, with a focus on the development of stable, high-performance CPL-active nanomaterials for applications in optoelectronics, bioimaging, and chiral photonics.