Preparation And Performance Study Of Electrochromic Materials Containing Triarylamine

Electrochromism?EC?can be defined as a reversible and visible change in the transmittance and/or reflectance of a material by applying different voltages or electric currents with the result of electrochemical oxidation or reduction.Electrochromic materials?ECMs?exhibit a reversible optical change in absorption or transmittance upon being electrochemically oxidized of reduced,which have extensive been applied as intelligent materials,such as smart windows,displays and electrochromic devices.In the first chapter,we introduce the tendency of ECand the content of this thesis.In the second and third chapter,two series of aromatic polyazomethines?PAMs?were prepared via the direct polycondensation from dicarboxaldehyde and differents kinds of diamine containing triarylamines.The PAMs displayed good solubility in many organic solvents which was beneficial for polymer film formation via spin coating.They all exhibited outstanding thermal stability with a loss of 10 wt%at temperatures above390 ^oC.These PAMs exhibited blue-green fluorescence in dichloromethane?CH₂Cl₂?solution.They exhibited halochromic properties with color changing from yellow to red or from yellow to blue.The highest occupied molecular orbital?HOMO?and lowest unoccupied molecular orbital?LUMO?energy levels of these PAMs were determined from cyclic voltammograms as-5.14 to-4.79 eV and-2.33 to-2.11 eV,respectively.The PAMs films not only had good electrochromic properties with high coloration efficiency,but also generated photovoltagic and photocurrent under simulated solar radiation.In the forth chapter,a series of poly?ester?s?PEs?were preparaed based on4,4'-dicarboxy-4"-N-phenothiazinyltriphenylamine.The PEs exhibited excellent solubility in many polar organic solvents and outstanding thermal stablility.The aromatic PEs exhibited photoluminescence?PL?emission maxima bands around 520nm?about in the green region?in THF solution.Most of them exhibit transparent in original state,and show color in oxidized state upon increasing voltage with the colour changed from colourless or lightyellow to red.The HOMO and LUMO energy levels of PEs were calculated to be from-4.97 to-4.34 eV and-2.57 to-2.11 eV,respectively.In addition,PEs generated photovoltagic and photocurrent under simulated solar radiation,which are promising materials in display and photovoltaic devices.In the fifth chapter,a series of poly?benzobisoxazoles??PBOs?were synthesized based on 4,4'-dicarboxy-4"-N-?2-naphthyl?-N-?phenyl?triphenylamine.The structures of polymers were confirmed by FT-IR spectroscopy which showed a strong absorption band at 1625 cm^-1,assigned to the azomethine?C=N?stretching.The electrochemical properties of PBOs were investigated by Cyclic voltammtry with the cast film in the DMSO solution,on an ITO-coated glass substrate as working electrode,which we got the values of oxidation potential distributed from 1.51 to 1.17V.And the HOMO and LUMO of PBOs were calculated by Density-functional theory to be at in the range from-5.38 to-4.85 eV and-1.92 to-1.58 eV,respectively.The properties prove that the polymers in this paper are multipurpose materials which will be subject of hole-transporting,electrochromic,chemical sensor application in near future.