Electrochromic properties of novel atmospheric pressure plasma jet-synthesized-organotungsten oxide films for flexible electrochromic devices

An investigation was conducted in electrochromic performance of organotungsten oxide WOxCy films deposited onto 40 Ω/square flexible PET (polyethylene terephthalate)/ITO (indium tin oxide) substrates using atmospheric pressure plasma jet (APPJ) at various precursor injection angles. A precursor [tungsten carbonyl, W(CO)6;TC] vapor, carried by argon gas, was injected into air plasma torch. The APPJ-synthesized WOxCy films were proven to offer extraordinary electrochromic performance. Cyclic voltammetry (CV) switching measurements indicated that only low driving voltages from −1 to +1 V are needed to offer reversible Li+ ion intercalation and de-intercalation in a 1 M LiClO4–propylene carbonate (PC) electrolyte. Light modulation with up to 72.5% transmittance variation, optical density change of 0.84 and coloration efficiency of 49.6 cm2/mC at a wavelength of 797.6 nm after 200 cycles of Li+ ion intercalation and deintercalation were obtained.