Electrochromic devices smart windows

G.A. Niklasson and C.G. Granqvist (2007) J. Mater. Chem., vol. 17, p. 127 - Electrochromics for smart windows Thin films of tungsten oxide and nickel oxide, and devices based on these . 

In general, the term electrochromism is used to describe the change in light absorption as a result of an electrochemical reaction. Recent interest in electrochromism stems from its potential applications in numerous devices, such as flat screen displays, antidazzle mirrors, smart windows, and others. 

Figure 33.1a illustrates the idea of the smart window. In this device a layer of electrochromic material and a layer of a transparent ion-conducting electrolyte are sandwiched between two optically transparent electrodes (OTEs). Indium-doped tin oxide on glass is used most commonly as the OTE. This material has very low... 

A general schematic for a smart window is shown in Figure 13.10. This device is, quite literally, two chemically modified electrodes sandwiched together. In this case, the films coating the electrode surfaces are electrochromic materials. A polymer electrolyte, analogous to that used in the fuel cell discussed earlier, is sandwiched between these two electrochromic material-coated electrodes. In a recent example of this concept by Habib and Maheswari of General Motors Research Laboratories [94], the cathodic electrochromic material was a tungsten oxide and the cathodic electrochromic material was the material Prussian blue, discussed in Section II of this chapter. It seems likely that electrochromic cells will soon find their way into the commercial marketplace. 

The considerable changes in the optical absorption of CPs during the dopingundoping process are at the basis of many proposals for electrochromical devices, such as smart windows, whose light transmission can be electrically controlled, and various display devices. Due to the drastic change that appears in their visible spectrum, PTh [122-124] and PAni [125] are... 

Figure 10 Electrochromic device, or smart window using a conducting polymer as the active material.

Electrochromic materials is a remarkable and productive research area over the last three decades since it has potential applications in smart window products, e-papers, optical shutters, transmissive and reflective displays, self-darkening mirror devices, and optical memories. The electrochromic effect has been observed in metal oxides (e.g., WO3),... 

Flexible electrochromic devices (ECDs) are becoming increasing important for their promising applications in many areas, such as the portable and wearable electronic devices, including smart windows, functional supercapacitors, and flexible displays. Typically, an ECD consists of four parts of substrate, conductive electrode, electrochromic material, and electrolyte. Enormous efforts have been made to improve the flexibility of ECDs including utilizing flexible polymer substrates and conductive materials. 

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