An electroactive poly(3,4-(2,2-dimethylpropylenedioxy)thiophene) (PProDOT-Me 2 ) thin film was electropolymerized by cyclic voltammetry technique, and its electrochemical and electrochromic properties were systematically studied. The prepared PProDOT-Me 2 thin film was electrochemically reversible, and it showed a linear relation between peak current with scan rates. The electrochemical impedance spectrum also indicated the diffusion limitation of the film during charge/discharge process. The film showed a good color contrast (60 %) with a low applying potential of 1.2 V. The electrochromic window (ECW) based on PPro-DOT-Me 2 film was fabricated and studied for its electrochromic performance. The color contrast of the device was achieved as 36 % at k max of 560 nm. The switching speed of fabricated ECW for coloring and bleaching were almost 0.7 s in a range of ?1.5 to -1.5 V. The fabricated device showed better cyclic current response and remarkable switching stability over 100 cycles. The novelty of the electrochromic window based on PProDOT-Me 2 is the maximum absorbance at photopic wavelength that would be highly sensitive to human eyes.

The dibenzyl derivative of poly(3,4-propylenedioxythiophene) (PProDOT-Bz 2 ) thin film is deposited onto ITO-coated glass substrate by electropolymerization technique. The electropolymerization of ProDOT-Bz 2 is carried out by a three-electrode electrochemical cell. The cyclic voltammogram shows the redox properties of electrochemically prepared films deposited at different scan rates. The thin films prepared were characterized for its morphological properties to study the homogeniety. Classic six-layer structure of PProDOT-Bz 2 electrochromic device using this material was fabricated and reported for the first and its characterizations such as spectroelectrochemical, switching kinetics, and chronoamperometric studies are performed. The color contrast of the thin film and the device achieved are 64 and 40%, respectively, at k max (628 nm). The switching time is recorded and the observed values are 5 s from the coloring state to the bleaching state and vice versa. The chronoamperometry shows that the device performed up to 400 cycles, and it is capable of working up to 35 cycles without any degradation.