Isomeric fluorescence sensors for wide range detection of ionizing radiations  

作　　者：Jimin Han Tianyu Yang Li Yang Yuanjian Li 

机构地区：[1]State Key Laboratory of Explosion Science and Technology of China,Beijing Institute of Technology,Beijing 100081,China [2]Chongqing Innovation Center,Beijing Institute of Technology,Chongqing 401120,China

出　　处：《Defence Technology（防务技术）》2024年第4期247-257,共11页Defence Technology

基　　金：financial support from the National Natural Science Foundation of China(Grant No.21801016);the Science and Technology on Applied Physical Chemistry Laboratory(Grant No.6142602220304)。

摘　　要：In order to achieve a wider range of ionizing radiations detection,novel fluorescence sensing materials have been developed that utilize the fluorescence enhancement phenomenon caused by the intramolecular photoinduced electron transfer(PET)effect.Two perylene diimide isomers PDI-P and PDI-B were designed and synthesized,and their molecular structures were characterized by high-resolution Fourier transform mass spectrometry(HRMS),nuclear magnetic resonance hydrogen and carbon spectroscopy(~1H and~(13)C NMR).The interaction between ionizing radiation and fluorescent molecules was simulated by HCl titration.The results show that combining PDIs and HCl can improve fluorescence through the retro-PET process.Despite the similarities in chemical structures,the fluorescent enhancement multiple of PDI-B with aromatic amine as electron donor is much higher than that of PDI-P with alkyl amine.In the direct irradiation experiments of ionizing radiation,the emission enhancement multiples of PDI-P and PDI-B are 2.01 and 45.4,respectively.Furthermore,density functional theory(DFT)and time-dependent density functional theory(TDDFT)calculations indicate that the HOMO and HOMO-1 energy ranges of PDI-P and PDI-B are 0.54 e V and 1.13 e V,respectively.A wider energy range has a stronger driving force on electrons,which is conducive to fluorescence quenching.Both femtosecond transient absorption spectroscopy(fs-TAS)and transient fluorescence spectroscopy(TFS)tests show that PDI-B has shorter charge separation lifetime and higher electron transfer rate constant.Although both isomers can significantly reduce LOD during PET process,PDI-B with aromatic amine has a wider detection range of 0.118—240 Gy due to its larger emission enhancement,which is a leap of three orders of magnitude.It breaks through the detection range of gamma radiation reported in existing studies,and provides theoretical support for the further study of sensitive and effective new materials for ionizing radiation detection.

关 键 词：Perylene imide Intramolecular PET Ionizing radiation detection Fluorescence sensor ISOMERS 

分 类 号：TP212[自动化与计算机技术—检测技术与自动化装置] X837[自动化与计算机技术—控制科学与工程]