Synthesis Of Polypyridyl Metal Iridium Compounds For Photodegradation Of Organic Dyes

Transition metal iridium(?)complexes have unique properties such as simple synthesis,good stability,easy adjustment of luminescence color,high quantum yield and long phosphorescence lifetime,and these advantages make them have great potential for development.Among the many ligands for the construction of metal iridium(?)complexes,pyridyl ligands with high stability,flexible coordination,and modifiable structure stand out.2,2':6',2''-tripyridine(tpy)is a tridentate ligand with good physicochemical properties,which can self-assemble with a large number of transition metal coordinates to form structurally stable supramolecular complexes.In previous researches of transition metal complexes,tpy-based cyclic metal iridium(?)complexes have been reported relatively rarely and usually use a single metal-ligated active center.Therefore,in this thesis,cyclic metal iridium(?)complexes with various types of metal coordination were constructed using dipyridyl and tripyridyl ligands,and their photophysical-chemical properties were further investigated to understand the effects of functional group introduction on photophysical-chemical properties,and the potential applications of these compounds in degrading organic dyes were explored as follows:(1)2-phenylpyridine and 2-(2,4-difluorophenyl)pyridine were used to synthesize the corresponding iridium(?)chloride bridging ligands,and then 4-bromo-2,2'-bipyridine and4,4'-dibromo-2,2'-bipyridine were introduced to obtain cyclometallic iridium(?)auxiliary ligands,the cyclometallic iridium(?)complexes Ir1-Ir6 were obtained by chelating with tpy groups,and the series of complexes were characterized and confirmed,and their photophysical and photodegradation of the organic dye rhodamine B(Rh B)was investigated.It was found that the introduction of tripyridine led to a red-shift of the maximum wavelength of the cyclic metal iridium(?)complexes and produced good degradation of the organic dye Rh B.(2)Based on<Tpy-Zn(II)-Tpy>,the rhombic bimetallic two-dimensional planar supramolecular structures M1 and M2 were synthesized by self-assembly of Ir5-Ir6?complex8 and Zn²⁺.The supramolecular structures were confirmed by 1D-2D NMR,high-resolution mass spectrometry and traveling wave ion mobility mass spectrometry,and the photophysical properties of M1 and M2 and their degradation of the organic dye rhodamine B were investigated experimentally.The fluorescence of M1 was weakened after assembly,while M2was red-shifted relative to the ligand,presumably due to the influence of the electron-absorbing fluorine atom,which restricted the vibrational bending of the structure and produced strong fluorescence emission,and both supramolecules showed good degradation effects on Rh B.(3)Different functional groups such as triphenylamine unit,carbazole unit and polyfluorene unit were introduced in compound 5,and transition metal platinum was introduced in the bipyridyl metal iridium(?)ligands Ir1 and Ir5 to obtain monodentate and bidentate platinum(II)metal compounds,and the obtained series of compounds were characterized and the photophysical properties of this series of compounds were investigated.