Electrochromism

About: Electrochromism is a research topic. Over the lifetime, 13097 publications have been published within this topic receiving 294637 citations.

Electrochromic Materials for optical switching devices

Abstract: The basic principles of electrochromism have been reported and discussed using the example of WO3, and some other important electrochromic materials have been described which have a number of interesting technical applications. Both compounds and materials used in ECDs were discussed and the principles of device design were portrayed, using as an example a reflective ASSD. By continuing the search for new electrochromic compounds and by further improving device design and cost optimization the applications of these materials are bound to increase.

Enhanced Contrast Dual Polymer Electrochromic Devices

Abstract: The ability to match two complementary polymers constitutes an important step forward in the design of electrochromic devices (ECDs). Here we show that the necessary control over the color, brightness, and environmental stability of an electrochromic window can be achieved through the careful design of anodically coloring polymers. For this purpose, we have constructed ECDs based on dimethyl substituted poly(3,4-propylenedioxythiophene) (PProDOT-Me2) as a cathodically coloring layer, along with poly[3,6-bis(2-ethylenedioxythienyl)-N-methyl-carbazole] (PBEDOT-NMeCz) and N-propane sulfonated poly(3,4-propylenedioxypyrrole) (PProDOP−NPrS) as anodically coloring polymers. Comparison of the results shows that using PProDOP−NPrS as the high band gap polymer has several advantages over the carbazole counterpart. The main benefit is the opening of the transmissivity window throughout the entire visible spectrum by moving the π−π* transition of the neutral anodically coloring material into the ultraviolet region. ...

Electrochromic Reactions in Manganese Oxides I . Raman Analysis

Abstract: Like nickel oxide, manganese oxide is a widely studied material in the primary batteries field. The reactions taking place during voltametric cycling of manganese oxides can be determined using in situ Raman spectroscopy. The main difficulty for the oxide identification is to obtain relevant Raman reference spectra because of the many possible compounds and, for some of these compounds, of their instability in the laser beam. As a consequence, several modifications of different tetra-, tri- and divalent manganese oxides and oxyhydroxides were carefully studied. The electrochromic behavior of three types of manganese oxides, two prepared by thermal oxidations and the other by electrochemical deposition, were then compared. The presence of nonstoichiometry in the pristine material was necessary to obtain a reversible electrochromic effect. The reaction during electrochromic cycling is more complicated than a simple passage from MnO[sub 2] to MnOOH.

Digital electrochromic mirror system

Abstract: A vehicular electrochromic rearview mirror system includes an interior electrochromic rearview mirror assembly and at least one exterior electrochromic rearview mirror assembly. Each mirror assembly includes an electrochromic reflective element that assumes a partial reflectance level in response to a signal applied thereto. A drive circuit applies a drive signal to each of the electrochromic reflective elements. The drive circuit may include a digital controller, a master drive circuit responsive to the digital controller to apply a first drive signal to one of the electrochromic reflective elements and a slave drive circuit responsive to the digital controller to apply a second drive signal to a second of the electrochromic reflective elements. The second drive signal may be derived from the first drive signal. The drive circuit may include a digital controller and a switching power supply controlled by the digital controller to produce a drive signal.