Ambient White Light Afterglow Emission Based on Triplet-to-Singlet Forster Resonance Energy Transfer

Compared with fluorescent materials, metal-free organic environmental afterglow materials, with larger Stokes shifts, longer lifetimes, higher S/N ratios, and sensitivities, present potential in new applications. However, achieving air stability and long lifetime organic afterglow systems with tunable emission color still remains a challenge. Herein, we have designed and synthesized luminescent copolymers exhibiting afterglow emission with tun-ability including white-light afterglow with considerable quantum yield [Commission Internationale de l'Eclairage (CIE) coordinates (0.32, 0.33), Phi(P) = 11%] in the amorphous state through the rarely reported triplet-to-singlet Forster resonance energy transfer (TS-FET). Also, they can emit different colors under UV light, including white-light [CIE coordinates (0.31, 0.33), Phi(Pl) = 27%]. This strategy was achieved by copolymerizing two simple-structured single-benzene-based compounds with acrylamide (AM) in different ratios. In addition, these materials can also be employed as a safety ink for paper paving the way for long lifetime luminescent material applications. [GRAPHICS] .

Automated summary

Metal-free organic environmental afterglow materials, compared with fluorescent materials, have potential in new applications due to their larger Stokes shifts, longer lifetimes, higher S/N ratios, and sensitivities. The challenge lies in achieving air stability and long lifetime organic afterglow systems with tunable emission color. However, through copolymerization of two compounds, luminescent copolymers with tunable afterglow emission and the ability to be used as safety ink for paper have been successfully designed and synthesized.