Electroactive Phosphorescent Iridium (â…¢) Complexes:Design,Synthesis And Application

Phosphorescent transition-metal complexes have many outstanding properties in the areas of optical physics, for instance, high luminescent quantum efficiency, long luminescent lifetime, easyto-adjust emission wavelength, prominent Stokes shift, rich excited-state properties etc., which make them been applied in plenty of fields, such as organic light-emitting diodes(OLEDs), organic electrical storage devices, light-emitting electrochemical cells(LECs), chemical and biological sensing, biological imaging and the like. The photophysical properties of phosphorescent iridium(III) complexes are not merely related to the structures of cyclomedtalating ligands, but sensitive to the stimulus of external environment. Therefore, phosphorescent iridium(III) complexes can be used to construct a kind of high performance stimuli-responsive phosphorescent materials. Electrical stimuliresponsive materials can be combined with the mature technology of traditional semiconductor devices and consequently they are promising for various of potential applications such as display devices, information storage devices, sensors and so forth, have aroused great interest of many research workers in these years. The main contents of this thesis is to design electrical stimuliresponsive phosphorescent iridium(III) complexes and expend their applications in the field of optoelectronics, including the following two parts.1.The design and synthesis of ferrocene modified iridium(III) complexes and application in organic electrical storage devicesFerrocene has stable and reversible redox center(Fe2+), we introduced ferrocene group into phosphorescent iridium(III) complexes trying to build electrical stimuli-responsive phosphorescent materials. There ferrocene modified iridium(III) complexes were designed and synthesized, including two ionic iridium(III) complexs and a neutral iridium(III) complex. All the complexes exhibited phosphorescence quenching and two of the ionic iridium(III) complexes restore phosphorescent emission after adding sodium hypochlorite solution. An organic storage device of sandwich structure based on the ferrocene modified neutral iridium(III) complex was prepared using the methed of vapor deposition. This device shows good electrical bistable properties and has a low starting voltage(-0.5 V), is a flash storage device.2. The design, synthesis and electrochromic phosphorescence of neutral iridium(III) complexOur group found that the introduction of the hydrogen bond(-NH) in cationic iridium(III) complex makes it shows electrochromic phosphorescence in solution in previous studies. To further study and elaborate the electrochromic phosphorescence mechanism of this kind of complexes, four neutral(III) complexes with hydrogen bond(-NH) was designed and synthesized. These neutral complexes have no response to the electric field in solution, but show electrochromic phosphorescence after mixing into tetrabutylammonium salt. This experiment proved that the migration of ion pairs is the key factor of electrochromic phosphorescence in solution of the neutral complexes. The material system of electrochromic phosphorescence has been expanded to neutral complexes.