| abstract |
The high contrast ratio and fast switching stacked electrochromic (EC) polymer device (50b) includes a transparent electrode (42), a cathodic EC polymer (44b), a gel electrolyte (46), and a counter electrode (52). Preferably, the cathode EC polymer is poly (3,4-propylene dioxythiophene) derivatives, PProDOT-Me 2. The counter electrode (52) is a conductive coating deposited on a transparent substrate, with preferred coatings comprising gold and highly conductive carbon. Lithography and sputtering can be used to pattern the gold layer, and screen printing can be used to pattern graphite as well. Experimental investigation of the preferred device has shown that, as electrochemically predicts, a high contrast ratio color change in transmissivity (> 50% T) can be obtained quickly (0.5 s) with 2.5 V applied, It shows that there is at least 10,000 reproducibility. PProDOT-Me bilayer EC device including a 2, as well as synthetic methods preferred EC polymers are also disclosed. |