Effect of Ar/O2 ratio on double-sided electrochromic glass performance

This paper reports the qualities of WO3 film and NiO film added to a counter electrode and their use in a double-sided electrochromic glass device. A mixture of argon and oxygen gasses with ratios of Ar/O2 of 1.5, 2, 3, and 5 were used for the deposition of the working electrode of WO3 film for EC glass. The structure of double-side EC glass consists of glass/ITO/NiO/electrolyte/WO3/ITO/glass/ITO/WO3/electrolyte/NiO/ITO/glass layers. The working electrode of WO3 film controls the color presented, the applied voltage controls the color depth, and the counter electrode controls the transparency in the bleached state. The double-sided EC glass with double WO3 films and double NiO films have faster coloration/bleaching rates than do single-sided EC glass. A mixture of Ar/O2 ratio of 3.0 has the best coloration/bleaching property of the ratios tested. Compared to the single-sided EC glass, the double-sided EC glass has lower transmittance of about 72% and 6% than the 78% and 12% during coloration and bleaching states in the visible light region with +1.5 V and −3.5 V applied.