Electrochemical Synthesis, Characterization And Electrochromic Properties Of Heterocyclic Aromatic Polymers

Electrochromic conductive polymer is a promising material, because it has a uniqueoptical and electrical property, which has been widely used in solar cells (PSCs),electrochromic device, sensors, polymer light-emitting diodes (PLEDs) and other fields. Mostof the heterocyclic aromatic conducting polymer generally has a high conductivity and areversible oxidation reductive. And in the visible-near infrared region, the heterocyclicaromatic conductive polymer has a fast response time, good stability and high contrast. Inaddition, we could tune the band gap/color of heterocyclic aromatic conductive polymerthrough structure modification, copolymerization or other method. This article is officiallybased on this principle, we synthesis of novel monomer by functional groups modified, andthen copolymerization and other means have been used to adjust the optical and electricalproperties of the polymer.In this article, we synthesized the1,4-bis(2-(3,4-ethylenedioxy)thienyl)benzene (EBE)and1,4-bis(3-methylthiophen-2-yl)benzene (BMTB) monomer via Still coupling reaction,synthesized the tris[4-(selenophene-2-yl)phenylamine (TSePA) monomer via Suzuki couplingreaction, and purchased high purity4H-cyclopenta[2,1-b:3,4-b’]dithiophene (CPDT) andpyrene (Py) from the reagent supplier. Then, we obtained several conductive polymers viaelectrochemical polymerized the corresponding monomer or monomer mixture in theelectrolyte solution.Next, cyclic voltammetry, Fourier transform infrared spectroscopy(FT-IR), UV-visiblespectroscopy(Uv-Vis), scanning electron microscopy(SEM) and spectroelectrochemical studies have shown that the four kinds of polymer (PEBE, P(EBE-co-BMTB), PTSePA,P(CPDT-co-Py)) film were observed distinctively electrochromic properties, and the methodof alter the band gap of polymer via group modified or copolymerization was effectively, thefour conductive polymer which possessing excellent optical and electrical properties, have thevalue of potential applications.In order to investigate the application possibility of these types of electrochromicpolymers in electrochromic devices, the obtained four conductive polymer were used as theanode material, the poly (3,4-ethylenedioxy thiophene)(PEDOT) was used as cathodematerials to assembled double style electrochromic device with sandwich-like structure. Thefour electrochromic devices were all have excellently photo-electric properties, proved thepossibility of their practical application.