Electrochromic device solid

Mastragostino M, et al. Polymer-based electrochromic devices. Solid State Ionics 1992 56 471-8. 

Judeinstein P., Livage J., Zarudiansky A. and Rose R. (1988) "An all gel electrochromic device" Solid State Ionics 28-30,1722-25. 

Orel B., Surca Vuk A., Jese R., Lianos P., Stathatos E., Judeinstein P., Colomban Ph. Development of sol-gel redox IJ/1 electrolytes and their application in hybrid electrochromic device. Solid State Ion. 2003 165 235-246... 

Electrochromic displays have some remarkable characteristics, such as memory effect, color variation, low mean power consumption etc. In most cases, however, electrochromic displays have been constructed as a solution containing system. The leakage of electrolyte solution and low stability are inevitable drawbacks for these electrochromic devices. Solid polymer electrolytes (SPEs) can be expected to improve these drawbacks [112, 113]. All solid state electrochromic displays based on SPEs should be developed. 

VAIVARS, G., AZENS, A., Granqvist, C.G, Proton conducting polymer composites for electrochromic devices. Solid State Ionics, 1999,119,269-73. 

Progress in the development of solid electrolytes is also being achieved from advances in several other fields of technology such as fuel and electrolysis cells, thermoelectric converters, electrochromic devices, and sensors for many chemical and physical quantities. 

Electrolytes for Electrochromic Devices Liquids are generally used as electrolytes in electrochemical research, but they are not well suited for practical devices (such as electrochromic displays, fuel cells, etc.) because of problems with evaporation and leakage. For this reason, solid electrolytes with single-ion conductivity are commonly used (e.g., Nafion membranes with proton conductivity. In contrast to fuel cells in electrochromic devices, current densities are much lower, so for the latter application, a high conductivity value is not a necessary requirement for the electrolyte. 

Bohnke, O., Applications of proton condnctors in electrochromic devices, in Proton Conductors Solids, Membranes and Gels—Materials and Devices, P. Colomban, Ed., Cambridge University Press, New York, 1992. 

The discussion of Brouwer diagrams in this and the previous chapter make it clear that nonstoichiometric solids have an ionic and electronic component to the defect structure. In many solids one or the other of these dominates conductivity, so that materials can be loosely classified as insulators and ionic conductors or semiconductors with electronic conductivity. However, from a device point of view, especially for applications in fuel cells, batteries, electrochromic devices, and membranes for gas separation or hydrocarbon oxidation, there is considerable interest in materials in which the ionic and electronic contributions to the total conductivity are roughly equal. 

Figure 2.30 Scheme of a solid electrochromic device. The device can operate with two electrochromic films as shown or with an electrochromic and an ion-storage film. 

Vroon, Z. Spee, C. Sol-Gel Coatings on Large Area Glass Sheets for Electrochromic Devices. J. Non-Cryst. Solids 1997, 218, 189-195. 

For the unique properties of PBs to be exploited, PBs must be deposited properly onto a solid support. It is highly desirable to prepare mechanically robust PBs films with controlled thickness, chemical composition and crystallinity, having ion-sieving membranes and electrochromic devices in mind [6], or to create regular patterns of PB-based single molecule magnets [13],... 

Ionic conductors have many practical applications. For example, solid ion conductors are used as solid electrolytes and electrode materials in -> batteries, fuel cells, - electrochromic devices and - gas sensors. 

Other materials being investigated include ferrocene with a bipyridinium salt,234 niobium oxide,235 nickel oxo-hydroxide,236 and cobalt oxohydroxide.237 The last is pale yellow in the reduced state and dark gray in the oxidized state. A typical electrolyte is lithium perchlorate in propylene carbonate. Solid electrolytes, such as a lithium salt (perchlorate, tetrafluoroborate, or triflate), in a polyepoxide238 or in a polyvinyl chloride gel in ethylene carbonate-propylene carbonate,239 lithium iodide in polyvinyl bu-tyral,240 and Naflon H (a polymeric perfluorocarbon-sulfonic acid),241 have also been tested. Some other systems use suspended particles between two panes of glass.242 When the particles are aligned by an electric field, the window becomes transparent. Combination photo-voltaic-electrochromic devices are under study.243... 

Current developments in battery technology, electrochromic devices (see Box 22.4) and research into electrically powered vehicles make use of solid electrolytes (see Box 10.3). The sodium/sulfur battery contains a solid 3-alumina electrolyte. The name (3-alumina is misleading since it is prepared by the reaction of Na2C03, NaN03, NaOH and AI2O3 at 1770K and is a non-stoichiometric compound of approximate... 

The electrolyte is probably the layer in which the maximum number of difficulties can occur. The use of a solid electrolyte, either a protonic conductor, or a lithium electrolyte is compulsory for practical applications. It can be an oxide [3], such as tantalum pentoxide, or a polymer [4]. The research field about the solid electrolytes is in fast expansion, with probable repercussions on the future of electrochromic devices. 

Electrochromic devices using poly(3-octylthiophene) associated to vanadium oxide as cathodically colouring material and a solution of polyethylene oxide (PEO) mixed with lithium perchlorate as solid electrolyte were tested [12]. Bithiophene properties were also discussed... 

The principle of electrochromic devices can be exploited in tinting ordinary window glass. Very thin polymer layers embedded in a colorless Solid electrolyte and sandwiched between two layers of glass may tint a window when an electric potential is applied. The d ee of tinting can be controlled by the size of the electric potentiaL... 

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