Precise Design and Deliberate Tuning of Turn-On Fluorescence in Tetraphenylpyrazine-Based Metal-Organic Frameworks  

作　　者：He-Qi Zheng Lin Zhang Mengting Lu Xiaoyan Xiao Yu Yang Yuanjing Cui Guodong Qian 

机构地区：[1]State Key Laboratory of Silicon Materials,Cyrus Tang Center for Sensor Materials and Applications,School of Materials Science Engineering,Zhejiang University,Hangzhou 310027,China

出　　处：《Research》2023年第1期341-351,共11页研究（英文）

基　　金：supported by the National Natural Science Foundation of China(Nos.52025131 and 61721005);Science Technology Department of Zhejiang Province(2022C01225).

摘　　要：The manipulation on turn-on fluorescence in solid state materials attracts increasing interests owing to their widespread applications.Herein we report how the nonradiative pathways of tetraphenylpyrazine(TPP)units in metal-organic frameworks(MOFs)systems could be hindered through a topological design approach.Two MOFs single crystals of different topology were constructed via the solvothermal reaction of a TPP-based 4,4',4",4"-(pyrazine-2,3,5,6-tetrayl)tetrabenzoic acid(H,TCPP)ligand and metal cations,and their mechanisms of formation have been explored.Compared with the innate lowfrequency vibrational modes of flu net Tb-TCPP-1,such as phenyl ring torsions and pyrazine twists,Tb-TCPP-2 adopts a shp net,so the dihedral angle of pyrazine ring and phenyl arms is larger,and the center pyrazine ring in TPP unit is coplanar,which hinders the radiationless decay of TPP moieties in Tb-TCPP-2.Thereby Tb-TCPP-2 exhibits a larger blue-shifted fluorescence and a higher fluorescence quantum yield than Tb-TCPP-1,which is consistent with the reduced nonradiative pathways.Furthermore,Density functional theory(DFT)studies also confirmed aforementioned tunable turn-on fluorescence mechanism.Our work constructed TPP-type MOFs based on a deliberately topological design approach,and the precise design of turn-on fluorescence holds promise as a strategy for controlling nonradiative pathways.

关 键 词：mechanism. PYRAZINE PHENYL 

分 类 号：O657.3[理学—分析化学]