Electrochromism color change process

Due to its electrochromic properties, i.e., a reversible color change upon application of suitable electric potential, tungsten trioxide has been employed and widely used in electronic displays, smart windows, simroofs, and rear and side view mirrors [60-63]. More recently, due to its chemical stability in acidic aqueous media and interesting photoelectrochemical properties, it has been proposed as a promising candidate in water photoelectrolysis processes [64—68]. 

Debad and Bard [674] recently described a new ladder polymer which displayed electrochromism. Its synthesis is depicted schematically in Fig. 14-24. The color change observed in this CP in acetonitrile with PFj dopant was pale orange (reduced) through pale green (neutral) to pale gray (oxidized). These polymers have been studied for a variety of applications, where their processibility especially comes in handy. These include 3rd-order NLO effects [511] and waveguiding [675]. 

Electrochromism is the property of a material or a system to change its optical properties (color) reversibly if an external potential is applied. It is associated with ion insertion/extraction processes, which can be presented schematically by ... 

An electrochromic display (BCD) is a thin solid state device that changes color reversibly when subjected to a small electrical potential. Since the doping processes of certain conducting polymers are accompanied by changes in the color, this effect has been conveniently exploited in the realization of BCD devices. Thin films of a conducting polymer polythiophene, for example, are red in the doped state and deep blue in the undoped state. 

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