Design,Synthesis And Luminescence Properties Study Of Manganese(?) Complexes With New Phosphine Oxide Compounds

For a long time,luminescent materials have shown great application potential in lighting,data storage,sensing,and flat panel displays.In recent years,luminescent manganese(?)complexes are developing rapidly due to their excellent photophysical properties,simple synthesis,low-cost and low-toxicity.Therefore,manganese(?)complexes are considered to be a class of luminescent materials with broad development prospects.In this thesis,a series of phosphine oxide compounds with different substituents have been designed and synthesized,and a variety of new manganese(?)complexes have been prepared through classical preparation methods using phosphine oxide compounds as ligands.In addition,the photophysical properties of phosphine oxide compounds and manganese(?)complexes were investigated.The main contents of this thesis are as follows:1.Design,synthesis and luminescence properties of persistent room-temperature phosphorescence materials based on phosphine oxide moleculesWith triphenylphosphine oxide as the skeleton,five phosphine oxide derivatives with the persistent room-temperature phosphorescence were synthesized through structural design.After irradiating the five compounds with 300 nm ultraviolet lamp for a period of time and then removing the light source,the compounds showed persistent room-temperature phosphorescence emission with different brightness and different colors.First,the crystal structures of the compounds were studied,and it was found that the crystal structures of the five compounds had multiple interactions.These weak interactions played an important role in reducing the random thermal motion of molecules and reducing non-radiative transitions.Next,the photophysical properties of the compounds in the crystalline state at the room temperature and low temperature were analyzed.The results showed that the phosphorescence lifetimes of the compounds were obvious differences in the two different environments.The phosphorescence lifetime of the compounds at the room temperature was between109.97 ms and 301.27 ms,and the phosphorescence lifetime of the compounds at the low-temperature was between 0.83 s and 1.29 s,indicating that the low temperature environment was beneficial to promote the emission of persistent phosphorescence.2.Design and synthesis of neutral manganese(?)complexes with phosphine oxide ligand for luminescent printingThree new neutral manganese(?)complexes were designed and prepared based on monodentate phosphine oxide ligand with different substituents.These manganese(?)complexes all show green light emission(?_em=498-512 nm).By varying the substituents,the CIE 1931 chromaticity diagram recorded the color changes from(0.102,0.517)to(0.166,0.655).Moreover,according to different substituents,the luminescence lifetimes of the three complexes in crystal state were distinctly different,ranging from 362?s(for manganese(?)complex with electron-withdrawing substituent)to663?s(for manganese(?)complex with electron-donating substituent).Compared with manganese(?)complex with electron-withdrawing substituent,the manganese(?)complexes with electron-donating substituents on phosphine oxide ligand exhibited blue-shifted emission wavelength and increased luminescence lifetime.Therefore,by changing the substituents of the phosphine oxide ligands,the photophysical properties of complexes can be tuned.Furthermore,the high-resolution luminescent printing has been successfully achieved with Mn Br₂ ethanol solution as an ink using a commercially available injet printer,realizing the information encryption.