Manipulating guest-responsive spin transition to achieve switchable fluorescence in a Hofmann-type framework  

作　　者：Xue-Ru Wu Shu-Qi Wu Zhi-Kun Liu Ming-Xing Chen Jun Tao Osamu Sato Hui-Zhong Kou 

机构地区：[1]Engineering Research Center of Advanced Rare Earth Materials(Ministry of Education),Department of Chemistry,Tsinghua University,Beijing 100084,China [2]Institute for Materials Chemistry and Engineering&IRCCS,Kyushu University,744 Motooka,Nishi-ku,Fukuoka 819-0395,Japan [3]Key Laboratory of Cluster Science of Ministry of Education,School of Chemistry and Chemical Engineering,Liangxiang Campus,Beijing Institute of Technology,Beijing 102488,China [4]Analytical Instrumentation Center,College of Chemistry and Molecular Engineering,Peking University,Beijing 100871,China

出　　处：《Science China Chemistry》2024年第10期3339-3346,共8页中国科学（化学英文版）

基　　金：supported by the National Natural Science Foundation of China(22271171,21971142,and 22371015);Japan Society for Promotion Science(JSPS)KAKENHI(24K17698 and 24H00466)。

摘　　要：The change of fluorescence emission manipulated by spin state transition attracts considerable attention owing to its potential applications in magneto-optical switching devices.Herein,we report two two-dimensional(2D)Hofmann-type spin crossover(SCO)metal-organic frameworks(MOFs)[Fe^(Ⅱ)(PNI)_(2){Ag^(Ⅰ)(CN)_(2)}_(2)]·CHCl_(3)(3Ag·CHCl_(3))and[FeⅡ(PNI)_(2){AuⅠ(CN)_(2)}_(2)]·CHCl_(3)(3Au·CHCl_(3))based on the fluorescent ligand N-(4-pyridylmethyl)-1,8-naphthalimide(PNI).Both complexes exhibit interesting SCO behaviors switched by guest solvent molecules,namely three-step transitions for the solvated complexes and complete onestep hysteretic SCO for the desolvated ones,verified by temperature-dependent magnetic susceptibility measurements,Mossbauer spectra,structural analyses,and differential scanning calorimetry measurements.Correspondingly,temperature-dependent fluorescence spectra exhibit double peaks(monomer and excimer emission)with both emission peaks change consistent with the change in SCO properties during the solvent molecule removal.In this study,we integrated guest-responsive SCO behavior into MOFs to manipulate the multistability of spin state and fluorescence switching,providing a rational strategy for the development of stimuli-responsive multifunctional materials.

关 键 词：spin crossover FLUORESCENCE multifunctional materials metal-organic frameworks Hofmann-type 

分 类 号：TB34[一般工业技术—材料科学与工程]