Ultra-long room temperature phosphorescence,intrinsic mechanisms and application based on host-guest doping systems  

作　　者：Jianmei Guo Yupeng Zhao Lei Ma Yongtao Wang 

机构地区：[1]College of Chemistry and Bioengineering,Guilin University of Technology,Guilin,541004,PR China [2]Tianjin International Center for Nanoparticles and Nanosystem,Tianjin University,Tianjin,300072,PR China

出　　处：《Chinese Journal of Structural Chemistry》2024年第9期21-29,共9页结构化学(英文)

基　　金：supported by the Natural Science Foundation of Guangxi Province(Nos.2024GXNSFAA010423 and 2020GXNSFAA159147);the National Natural Science Foundation of China(No.21766030).

摘　　要：To construct efficient room-temperature phosphorescence(RTP)doping systems by simple doping methods,isomers 2-(2-(9H-carbazol-9-yl)benzyl)malononitrile(o-CzCN),2-(3-(9H-carbazol-9-yl)benzyl)malononitrile(m-CzCN)and 2-(4-(9H-carbazol-9-yl)benzyl)malononitrile(p-CzCN)were designed and synthesized by choosing commercial carbazole.Based on the structure-function relationships of three isomers and excellent compatibility between carbazole and benzocarbazole,2-(3-(9H-carbazol-9-yl)benzyl)malononitrile(Lm-CzCN)and 2-(3-(5H-benzo[b]carbazol-5-yl)benzyl)malononitrile(m-BCzCN)were prepared by self-made carbazole and 2-naphthyl-amine.Then,Lm-CzCN/m-BCzCN was constructed and optimized by dissolution and rapid evaporation,as well as tuning the mass ratios between Lm-CzCN and m-BCzCN.Lm-CzCN shows excitation dependent RTP and afterglow lifetimes,as well as concentration dependent RTP emission in poly(vinyl alcohol)(PVA)films,while 1%m-BCzCN@PVA film emits bright green afterglow,with RTP and afterglow lifetimes of 2.303 and 17 s in turn,as well as RTP quantum yield of 0.22.More importantly,Lm-CzCN/m-BCzCN presents ultra-long room temperature phosphorescence,with RTP and afterglow lifetimes of 597.58 ms and 8 s,respectively.Moreover,crystals m-CzCN and p-CzCN,as well as Lm-CzCN/m-BCzCN can be excited by visible light of 440 nm,showing yellow afterglow of 1-4 s.Noteworthy,polymorphism o-CzCNy and o-CzCN_(B) were found,whose different emission was investigated by molecular conformation,intermolecular arrangement and stacking patterns.Finally,multiple encryptions were successfully constructed based on the different luminescent properties.

关 键 词：Room-temperature phosphorescence Host-guest doping ISOMER Benzocarbazole POLYMORPHISM 

分 类 号：TB34[一般工业技术—材料科学与工程]