posted on 2022-01-20, 17:04authored byParvej Alam, Tsz Shing Cheung, Nelson L. C. Leung, Jianyu Zhang, Jing Guo, Lili Du, Ryan T. K. Kwok, Jacky W. Y. Lam, Zebing Zeng, David Lee Phillips, Herman H. Y. Sung, Ian D. Williams, Ben Zhong Tang
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.