Electrochromism in WO_3 evaporated films

WO_3蒸着膜のエレクトロクロミズム (III)

Electrochromism in WO_3 evaporated films

Creators Ozaki Satoru

Creators Kaneko Hiroko

Creators Miyata Naoyuki

Creators Miyake Kiyoshi

The performance characteristics of EC display devices were investigated. The devices used in this study were EC cells having a SnO_2 : Sb-WO_3-liquid electrolyte-SnO_2 : Sb structure. The WO_3 films were prepared on SnO_2 : Sb coated glass substrate by thermal evaporation at pressure below 1.5×(10)^<-5> Torr. The thickness of the WO_3 films were in the range of 2000-3900A. The liquid electrolytes used were H_2SO_4,Li_2SO_4,Na_2SO_4 and K_2SO_4. For any liquid electrolyte, a bule color appeared for EC devices with transparent electrode negatively biased. The optical transmission spectrum of the WO_3 films showed a peak at around 3800A and a broad bottom peaked around 9000A. Coloration current response of the liquid EC cells showed a t^<-1/2> dependence of current, and bleaching current response of the EC cells did a t^<-3/4> dependence of current under the condition of dc applied voltage below 2 V across the EC cells. Under the dynamic condition, corrosion of the counter electrode were with the forward biased (bleaching) greated than with the reverse biased (coloration).

[ISSN]0372-7661

[NCID]AN00244228