High contrast solid-state electrochromic devices from substituted 3,4-propylenedioxythiophenes using the dual conjugated polymer approach

Solid-state electrochromic windows from 3,4-propylenedioxythiophene (ProDOT) derivatives using dual polymer electrochromic architecture were fabricated and their electro-optical characteristics were recorded. DibenzylProDOT (DiBz-ProDOT) and biphenylmethyloxymethyl ProDOT (BPMOM-ProDOT) were used as cathodically coloring polymers, whereas bis(2-(3,4-ethylenedioxy)thienyl)-N-methyl carbazole (BEDOT-NMCz) was used as their complementary anodically coloring polymer. Straightforward assembly of the devices was designed by means of using a UV photo-curable gel. These devices exhibited response speeds of approximately 1 s with photopic contrasts as high as 52% for the complete device, and were found to exhibit good stability under open circuit conditions. Convenience of reporting photopic values to characterize electrochromic devices compared to reporting contrasts at a single wavelength is remarked. (c) 2007 Elsevier B.V. All rights reserved.