Lithium electrochromic properties of atmospheric pressure plasma jet-synthesized tungsten/molybdenum-mixed oxide films for flexible electrochromic device

An investigation is conducted into the enhanced lithium electrochromic performance of flexible tungsten/molybdenum-mixed oxide (WMo (x) O (y) C (z) ) films deposited onto 40 Omega/a- flexible polyethylene terephthalate/indium tin oxide substrates, using a low temperature (similar to 23 A degrees C) atmospheric pressure plasma-enhanced chemical vapor deposition with an atmospheric pressure plasma jet at various substrate distances. The rapid synthesis of flexible WMo (x) O (y) C (z) films is performed by injecting the mixed hexacarbonyl and precursors W(CO)(6) and Mo(CO)(6) into an air plasma jet and exposing the substrate in the plasmas for short exposure durations (19-34 s) at various substrate distances. The flexible WMo (x) O (y) C (z) films possess the remarkable Li+ ion electrochromic performance, even though after being bent 360A degrees around a 2.5-cm diameter rod for 1,000 cycles and tested for 200 cycles of reversible Li+ ion intercalation and deintercalation in a 1-M LiClO4-propylene carbonate electrolyte, respectively, by a potential sweep switching at the scan rates of +/- 50 mV/s from the potential of -1 to 1 V and a potential step switching at the potentials of -1 and 1 V. Significant optical modulation and optical density change of up to 71.2 % and 0.73 at a wavelength of 622 nm are respectively achieved.