Light-triggered fluorochromic cholesteric liquid crystal elastomer with hydrogen-bonded fluorescent switch: dualmodal-switchable circularly polarized luminescence  

作　　者：Siyang Lin Tianqi Ren Xianyu Meng Wenxin Kang Jinbao Guo 

机构地区：[1]Key Laboratory of Carbon Fibers and Functional Polymers,Ministry of Education,College of Materials Science and Engineering,Beijing University of Chemical Technology,Beijing 100029,China

出　　处：《Science China Chemistry》2024年第8期2719-2727,共9页中国科学（化学英文版）

基　　金：supported by the National Natural Science Foundation of China (52073017, 51773009);the High Performance Computing Platform of Beijing University of Chemical Technology。

摘　　要：Solid materials with dynamically tunable circularly polarized luminescence(CPL) feature higher security levels and devicefriendly characteristics, showing great superiority in the field of information technology and anti-counterfeiting. To address the limited photoisomerization of fluorescent photoswitch in CPL-active solid materials, here a cholesteric liquid crystal elastomer(CLCE) containing a hydrogen-bonded(H-bonded) polymerizable fluorescent switch AHBA-PSD is prepared. Owing to the good flexibility and low glass-transition temperature of CLCE, AHBA-PSD shows a fast and fully reversible photocyclization/cycloreversion with fluorochromic behavior in CLCE. Further, by controlling the spectral overlapping area between the emission and reflection bands, the CLCE exhibits a strong CPL with a g_(lum) value of up to 0.76 accompanied by a reversible phototunable CPL signal. Meanwhile, the H-bond helps to stabilize the mechanical property, and the force-induced switching-off of CPL signal could be achieved due to the destroyed helical structures by external force. Finally, an automatically-recognized identification card with abundant chiroptical information is demonstrated.

关 键 词：cholesteric liquid crystal elastomer circularly polarized luminescence fluorescent photoswitch DIARYLETHENE photoismerization 

分 类 号：O644.1[理学—物理化学] O753.2[理学—化学]