Electrochromic organic polymer synthesis and devices utilizing electrochromic organic polymers

摘要

Large contrast ratio and rapid switching laminated electrochromic (EC) polymer device includes transparent electrode, cathodic EC polymer, gel electrolyte, and counter-electrode. Preferably the cathodic EC polymer is a poly(3,4-propylenedioxythiophene) derivative, PProDOT-Me₂. Counter-electrode is a conductive coating deposited on transparent substrate, with preferred coatings including gold and highly conductive carbon. Lithography and sputtering can be employed to pattern a gold layer, while screen printing can be employed to similarly pattern graphite. Empirical studies of preferred device indicate a color change of high contrast ratio of transmittance (50% T) is rapidly (0.5–1s) obtained upon applied 2.5V, repeatable to at least 10,000 times, as estimated by electrochemistry. Dual layer EC devices including PProDOT-Me₂ are also disclosed, as are methods for synthesizing preferred EC polymers. Preferred synthesis method for obtaining PProDOT-Me₂ involves refluxing reagents in toluene in the presence of catalyst, while continually removing methanol byproduct from refluxing solution.