SOLID-STATE ELECTROCHROMIC DEVICES COMPOSED OF PRUSSIAN BLUE, WO3, AND POLY(ETHYLENE OXIDE)-POLYSILOXANE HYBRID-TYPE IONIC CONDUCTING MEMBRANE

The preparation of a new type of poly(ethylene oxide)-polysiloxane hybrid (PEOS) with its application to the construction of solid-state electrochromic devices was studied. The PEOS was given as a colorless and elastic membrane by condensation of a bis(silylpropyl) ether of oligo(ethylene oxide) and a polyalkoxysilane in the presence of LiClO4 (2-5 mole percent). The ionic conductivity reached 10-3 S cm-1 when PEOS was swollen with propylene carbonate by 160% in weight. A transparent-type solid-state electrochromic device composed of Prussian blue- and WO3-coated electrodes with PEOS was prepared, switching of which was slower by a factor of 1.5-2.0 as a function of half-time of coloration and bleaching compared with the corresponding liquid-type cell.