Synthesis, Characterization And Applications Of Iridium(Ⅲ)Complexes

Transitional metal complexes(especially iridium(Ⅲ)complexes)which are characteristic with metal-to-ligand charge-transfer transition(MLCT)and intraligand(π→π*)transition exhibit advantageous noticeable photophysical and photochemical properties,such as the high luminescent quantum yield,more prominent color features and long lifetime.In recent years,iridium(Ⅲ)complexes are widely used in light-emitting diodes(OLEDs),light-emitting electrochemical cell(LEECs),chemical sensing,biological imaging,aerospace coatings and optical catalyst.However,most of these complexes are only soluble in the organic solvent.It is important to improve the water-soluble properties of the iridium(Ⅲ)complexes for the application in the biological field.At the same time,there are also more and more research on the chemical sensors based on the iridium(Ⅲ)complexes.In this paper,a series of water-soluble iridium(Ⅲ)complexes were designed and synthesized by introducing a hydrophilic group into the complexes which expanded its application in biological analysis.And a series of iridium(Ⅲ)complexes by the use of ligand-modified special group were also designed and synthesized for the chemical sensing.The first chapter,the basic concepts of photophysical iridium(Ⅲ)complexes and luminescence properties were introduced,and the research on the iridium(Ⅲ)complexes in OLEDs,chemical sensing,ECL,biomarkers and imaging,photocatalysis,coatings and aviation application were also summarized.The second chapter,a kind of sugar with multi-hydroxyl group were introduced into bipyridyl ligand,which combined with different cyclometalated ligands(2-(4-carboxyphen-yl)pyridine,2-(2,4-difluorophenyl)pyridine,2-methyl-3-benzene and quinoxaline)to obtain three kinds of water-soluble iridium(Ⅲ)complexes.The complexes were characterized by 1H NMR,MS and elemental analysis.Photophysical,electrochemical properties and cell imaging of these complexes were also studied.The third chapter,we synthesized a series of pH-sensitive iridium(Ⅲ)complexes by modifying the ancillary ligands.Ancillary ligands included bipyridine,4,4’-dihydroxy-2,2’-bipyridine,4,4’-diamino-2,2’-bipyridine,4,4’-dimethoxy-2,2’-bipyri dine and 4,4’-dimethylol-2,2’-bipyridine.The photophysical and photochemical properties of these complexes of were studied.