THEME: "Enlightening the recent advances in Biopolymers & Polymer Chemistry"
Nanjing University of Posts and Telecommunications
Title: Construction of high-performance organic afterglow polymers and their applications
Dr. Runfeng Chen, now is a professor of Nanjing University of Posts & Telecommunications and vice head of the institute of advanced materials. He received his B.E. degree in Polymer Science and Engineering and M.S. degree in Material Science of Tongji University. He did his Ph.D. in Fudan University and his postdoctoral work at the National University of Singapore with Prof. Xiaogang Liu. He joined the faculty of Nanjing University of Posts and Telecommunications in 2006. And, Dr. Chen won the Jiangsu Province’s Science and Technology Award (class II) in 2019 as the first principle investigator and National Natural Science Award (class II) in 2018 as the fourth principle investigator. Current, his research interests are in the development of new-concept optoelectronic materials and devices by rationally manipulating excited states of organic materials.
Organic afterglow materials with luminescent lifetime over 100 ms are highly attractive in the recent investigations of new-concept organic electronic materials and advanced device applications. We carefully investigated the emission behavior of OURTP materials in the aggregated states to reveal the mechanism for their diversified and interesting luminance at room temperature. We proposed a synergistic strategy to modulate the afterglow performance of polymers by harmonizing the nonconjugated cluster-triggered emission with conjugated aromatic luminance in flake form through copolymerization and aggregation engineering. We achieved hyperafterglow emission through sensitizing and stabilizing isolated fluorescence chromophores by radical binary copolymerization to combine afterglow host and multi-resonance thermally activated delayed fluorescence guest in a single-component copolymer. Bright multicolor hyperafterglow polymers with maximum afterglow efficiency up to 88.9%, minimum full-width at half-maximum (FWHM) of 38 nm and ultralong lifetime of 1643.8 ms under ambient conditions are developed. We also stabilized triplet excitons of phosphors by embedding in tri-component tri-hapto self-assembled 2D hydrogen-bonded superlattices, which not only enables deep-blue POA with high PhQY (up to 65%), ultralong lifetime (over 1300 ms) and the highest figure-of-merit at room temperature, but also achieves excellent stability capable of resisting quenching effects of oxygen, solvent, pressure, light and heat. With these extraordinary high-performance organic afterglow polymers, rewritable encryption papers were constructed, on which the high-resolution anti-counterfeiting patterns can be water-jet printed and multi-color and multi-level encryption is realized by energy transfer from the blue afterglow polymer to commercial dyes. We also present an X-ray-excitable organic room temperature phosphorescence for afterglow scintillator, which is highly attractive for the X-ray imaging. Those findings as well as various applications based on the ultralong emission lifetime of organic afterglow polymers will be presented and discussed.