Electrosynthesis Of Conducting Polyindole Derivatives And Investation Of The Electrochromic Properties

The preparation of high-performance conductive polyindole and the study of itselectrochromic properties has been the current research focus. Electrochemicalpolymerization has been proved to be one of the most useful approaches forconducting polymer synthesis. In this dissertation, poly(indole-6-carboxylic acid)(PI6CA), Copolymer of 5-cyanoindole (CNIn) with 3,4-ethylene dioxythiophene(EDOT), poly(5-formylindole) (P5FIn) were successfully prepared by electrochemicalpolymerization in acetonitrile (ACN). The electrochromic properties of thesehigh-qualitycorrespondingpolymers werealsoinvestigated.1. The electrosyntheses of a novel high-quality polyindole derivative,poly(5-formylindole) (P5FIn) in acetonitrile are reported. It is interesting that P5FInfilm with high fluorescence quantum yields and photochemical stabilityfor the importof aldehyde group. The conductivities of the film is tested to be 2.43×10^-2 S cm^-1.Spectroelectrochemical studies manifest that P5FIn with high transmissivityand shortswitch time. Furthermore, a dual type electrochromic device (ECD) based on P5FInand poly(3,4-ethylenedioxythiophene) (PEDOT) was constructed and itselectrochromic properties were investigated. The ECD exhibits color changed fromgreen (neutral) to dark blue (oxidized) with a good open circuit memory and robustcyclelife.2. Poly(indole-6-carboxylic acid) (PI6CA) film, a novel soluble nanostructuredpolyindole derivative, was synthesized electrochemically by direct oxidation ofindole-6-carboxylic acid (I6CA) in acetonitrile + 0.1 mol L^-1 TBATFB. The resultingpolymer were performed good electrochemical stability and thermostability. The conductivities of the sample is tested to be 0.28 S cm^-1. Furthermore, thespectroelectrochemical and electrochromic properties of the polymer films wereinvestigatedwithUV–visspectroscopy .Inaddition,adualtypeelectrochromicdevicebased on PI6CA and PEDOT was constructed and its spectroelectrochemicalproperties were investigated. The electrochromic device exhibits color change fromgreen to dark bluein a short switching time and visible constract together with a goodopencircuitmemory.3.Copolymer of 5-cyanoindole(CNIn) with 3,4-ethylene dioxythiophene (EDOT)was electrochemically synthesized and characterized. Resulting copolymer film hasgood electrochemical stability and thermostability.In addition, the copolymer showdistinct electrochromic properties, could change bewteen brown and blue.And itsapplication in electrochromic devices (ECDs) are discussed. The electrochromicdevice exhibits color change from green to dark blue in a short switching time andvisibleconstracttogetherwithagoodopencircuitmemory.