The electrochemical fabrication of electroactive polymer films from diamide- or diimide-cored N-phenylcarbazole dendrons for electrochromic applications

Two series of novel diamide- or diimide-cored N-phenylcarbazole dendrons were synthesized from condensation reactions of 3,6-di(carbazol-9-yl)-N-(4-aminophenyl)carbazole (NH2-3Cz) with aromatic dicarboxylic acids and tetracarboxylic dianhydrides, respectively. These dendrons can be electropolymerized into crosslinked poly(amide-carbazole) and poly(imide-carbazole) films on the electrode surface in an electrolyte solution via the coupling reactions between carbazole radical cations. Cyclic voltammograms of the electro-generated polymer films showed two reversible oxidation redox couples accompanied by a color change from the colorless neutral state to the yellow-green and blue oxidized forms in the range of 1.11–1.34 V. The electrochromic behavior of the film is clearly interpreted on the basis of spectroelectrochemical studies. Single layer electrochromic cells were also fabricated as preliminary evaluation for their application as electrochromic devices.