Electrochromic Device Based on Tungsten Oxide and on Nafion-H as Polymeric Electrolyte

We describe the preparation, electrical and optical characterization of a prototype of a nearly solid-state electrochromic device. It is fabricated with Nafion-H, a polymeric electrolyte, and involves cathodically coloring tungsten trioxide doped with molybdenum. The device switches rapidly with the applied potential ranging from −2.4 up to 0.8V, between blue and transparent state. The corresponding integrated photopic (Tp) and solar (Ts transmittance is Tp (bleached) = 70.7%, Ts (bleached) = 59.6%, Tp (colored) = 15.5%, and Ts (colored) = 12.2%.