Fabrication of fast switching electrochromic window based on poly(3,4-(2,2-dimethylpropylenedioxy)thiophene) thin film

An electroactive poly(3,4-(2,2-dimethylpropylenedioxy)thiophene) (PProDOT-Me₂) thin film was electropolymerized by cyclic voltammetry technique, and its electrochemical and electrochromic properties were systematically studied. The prepared PProDOT-Me₂ 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 PProDOT-Me₂ film was fabricated and studied for its electrochromic performance. The color contrast of the device was achieved as 36 % at λ_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-Me₂ is the maximum absorbance at photopic wavelength that would be highly sensitive to human eyes.