High-Rate Deposition of Electrochromic Organotungsten Oxide Thin Films for Flexible Electrochromic Devices by Atmospheric Pressure Plasma Jet: The Effect of Substrate Distance

High-rate deposition of electrochromic organotungsten oxide (WO(x)C(y)) films onto flexible PET (polyethylene terephthalate)/ITO (indium tin oxide) substrates by atmospheric pressure-plasma enhanced chemical vapor deposition (AP-PECVD) with atmospheric pressure plasma jet (APPJ) under various substrate distances is investigated. A precursor (tungsten carbonyl, W(CO)(6), TC) vapor, carried by argon gas, is injected into air plasma torch for the synthesis of WO(x)C(y) films. Uniform light modulation up to 1 cm wide on PET/ITO/WO(x)C(y) is produced, while the moving PET/ITO substrate is exposed to a 0.3 cm diameter plasma torch at room temperature (approximate to 23 degrees C) and atmospheric pressure. The porous APPJ-synthesized WO(x)C(y) films result in fast responses using potential steps for coloration of 11.5 s at -1V and bleaching of 7.2 s at +1V, respectively. APPJ-synthesized WO(x)C(y) films offer noteworthy electrochromic performance in light modulation with up to 73.0% of transmittance variation, optical density change of 0.72 and coloration efficiency of 67.7 cm(2).C(-1) at a wavelength of 800 nm.