Organic Long-Persistent Luminescence from a Single-Component Aggregate

Long-persistent luminescence (LPL), also known as afterglow, is a phenomenon in which the material shows long-lasting luminescence after the cessation of the excitation source. The research of LPL continues to attract much interest due to its fundamental nature and its potential in the development of the next generation of functional materials. However, most of the current LPL materials are multicomponent inorganic systems obtained after harsh synthetic procedures and often use rare-earth metals. Recently, metal free organic long-persistent luminescence (OLPL) has gained much interest because it can bypass many of the disadvantages of inorganic systems. To date, the most successful method to generate OLPL systems is to access charge-separated states through binary donor-acceptor exciplex systems. However, it has been reported that the ratios of the binary systems affect OLPL properties, complicating the reproducibility and large-scale production of OLPL materials. Simpler OLPL systems can overcome these issues for the benefit of the development and adoption of OLPL systems. Here, we report on the rational design and synthesis of a single-component OLPL system with detectable afterglow for at least 12 min under ambient conditions. This work exemplifies an easy design principle for new OLPL materials. The investigation of the material provides valuable insights toward the generation of OLPL from a single-component system.

Automated summary

Long-persistent luminescence (LPL), also known as afterglow, is a phenomenon where a material continues to emit light after the excitation source is turned off. It has attracted much interest due to its fundamental nature and potential in developing new functional materials. Most current LPL materials are complex inorganic systems that require harsh synthetic procedures and rare-earth metals. However, metal-free organic long-persistent luminescence (OLPL) has gained interest as it overcomes some of the disadvantages of inorganic systems. The most successful method to generate OLPL systems is through binary donor-acceptor exciplex systems, but the ratios of the binary systems can complicate reproducibility and large-scale production. Therefore, simpler OLPL systems are needed for easier design and production.