Showing papers on "Electrochromic devices published in 2001"
TL;DR: Mesoporous semiconducting films consisting of preferentially orientated monoclinic-phase nanocrystals of tungsten trioxide have been prepared using a novel version of the sol-gel method, combining excellent photoresponse to the blue region of the solar spectrum, up to 500 nm, with good transparency at wavelengths larger than 550 nm.
Abstract: Mesoporous semiconducting films consisting of preferentially orientated monoclinic-phase nanocrystals of tungsten trioxide have been prepared using a novel version of the sol−gel method. Transformations undergone by a colloidal solution of tungstic acid, stabilized by an organic additive such as poly(ethylene glycol) (PEG) 300, as a function of the annealing temperature have been followed by means of a confocal Raman microscope. The shape and size of WO3 nanoparticles, the porosity, and the properties of the films depend critically on preparation parameters, such as the tungstic acid/PEG ratio, the PEG chain length, and the annealing conditions. Well-crystallized WO3 films combine excellent photoresponse to the blue region of the solar spectrum, up to 500 nm, with good transparency at wavelengths larger than 550 nm. Particular applications of these nanocrystalline WO3 films include photoelectrochemical and electrochromic devices.
961 citations
TL;DR: In this article, the most important examples from the major classes of electrochromic materials are highlighted, including car mirrors, windows and sun-roofs of cars, windows of buildings, displays, printing, and frozen-food monitoring.
Abstract: Many inorganic and organic materials exhibit redox states with distinct electronic (UV-vis) absorption bands. When the switching of redox states generates new or different visible region bands, the material is electrochromic. Electrochromic materials are currently attracting much interest in academia and industry for both their fascinating spectroelectrochemical properties and their commercial applications. In this review some of the most important examples from the major classes of electrochromic materials are highlighted. Examples of their use in both prototype and commercial electrochromic devices are illustrated including car mirrors, windows and sun-roofs of cars, windows of buildings, displays (see Figure), printing, and frozen-food monitoring.
820 citations
TL;DR: A new type of electrochromic mirror electrode based on reversible uptake of hydrogen in nickel magnesium alloy films is reported in this paper, where a thin overlayer of palladium was found to enhance the kinetics of hydrogen insertion and extraction, and to protect the metal surface against oxidation.
Abstract: A new type of electrochromic mirror electrode based on reversible uptake of hydrogen in nickel magnesium alloy films is reported. Thin,magnesium-rich Ni-Mg films prepared on glass substrates by cosputtering from Ni and Mg targets are mirror-like in appearance and have low visible transmittance. Upon exposure to hydrogen gas or on reduction in alkaline electrolyte, the films take up hydrogen and become transparent. When hydrogen is removed, the mirror properties are recovered. The transition is believed to result from reversible formation of Mg2NiH4 and MgH2. A thin overlayer of palladium was found to enhance the kinetics of hydrogen insertion and extraction,and to protect the metal surface against oxidation.
336 citations
269 citations
TL;DR: In this article, X-ray diffractometry (XRD), X-Ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), UV-visible (UV-Vis) spectrography and cyclic voltammetry were used to characterize Ceria (CeO2) films.
185 citations
176 citations
Patent•
19 Jun 2001TL;DR: Coupling of anodic electrochromic compounds by a covalent bond or a bridge link, which provides for electronic communication between the coupled anodic ECC compounds, results in coupled ECCs which exhibit greater stability as well as electro chromic activity that differs from the monomeric ECC compound.
Abstract: Coupling of anodic electrochromic compounds by a covalent bond or a bridge link which provides for electronic communication between the coupled electrochromic compounds results in coupled electrochromic compounds which exhibit greater stability as well as electrochromic activity that differs from the monomeric electrochromic compounds. Extension of the absorption spectrum into the near-infrared region of the spectrum is frequently observed. The coupled electrochromic compounds are highly suitable for use in electrochromic media used to produce electrochromic devices.
148 citations
Patent•
07 Sep 2001TL;DR: In this article, an electrochromic device, such as a window or mirror, is disclosed that includes first and second substrates each having an inner surface spaced apart from one another to define a chamber.
Abstract: An electrochromic device, such as a window or mirror, is disclosed that includes first and second substrates each having an inner surface spaced apart from one another to define a chamber, first and second electrodes carried on the inner surface of the second substrate and disposed thereon to be electrically isolated from one another, and an electrochromic medium disposed in the chamber. The electrodes may be disposed on the inner surface of the second substrate in substantially co-planar relation. Alternatively, the electrodes may be arranged in a stacked relation, with a layer of dielectric material provided therebetween.
133 citations
Patent•
21 Dec 2001
TL;DR: In this paper, the use of ionic liquids as electrolytes for the fabrication of long-lived, highly stable elecrochemical actuators, electrochemical capacitors and electrochemical batteries having conjugated polymers (10, 14) as active electrodes was discussed.
Abstract: The present invention relates to the electrochemistry of conjugated polymers (10, 14) in ionic liquids (18) and the development and fabrication of long-lived, highly stable conjugated polymer electrochemical devices by using ionic liquids (18) as electrolytes. More specifically, the invention relates to the use of ionic liquids (18) as electrolytes for the fabrication of long-lived, highly stable elecrochemical actuators, electrochemical capacitors and electrochemical batteries having conjugated polymers (10, 14) as active electrodes as well as for the fabricatin of long-lived, highly stable electrochromic devices with polyaniline and polythiophene as coloration materials.
93 citations
TL;DR: In this article, the authors presented the development of advanced materials suitable for use as electrochromic thin films (EC), ion storage layers and transparent conductors (TC) in EC devices.
88 citations
Patent•
31 Jul 2001TL;DR: In this article, an electrochromic aircraft window assembly includes an outboard pane assembly and a fog preventing the assembly from forming a chamber between the outboard and the window assembly.
Abstract: An electrochromic aircraft window assembly includes: a) an outboard pane assembly; and b) a fog preventing electrochromic pane assembly spaced from the outboard pane assembly and defining a chamber therebetween, the fog preventing electrochromic pane assembly having: i) a first substrate having a first surface including a first conductive coating and a second surface including a second conductive coating; ii) a second substrate spaced from the first substrate, the second substrate having a first surface including a third conductive coating, the second surface of the first substrate and the first surface of the second substrate facing each other in spaced-apart relation to define a chamber therebetween; iii) an electrochromic medium contained in the chamber and in contact with the second and the third conductive coatings, the electrochromic medium having a luminous transmittance that varies upon application of an electrical potential through the electrochromic medium; iv) facilities for applying electrical current to the first conductive coating to heat the first conductive coating, thereby preventing fogging of the window assembly; and v) facilities for applying electrical current to the second and the third conductive coatings to establish the electrical potential through the electrochromic medium and vary the variable luminous transmittance of the electrochromic medium.
TL;DR: In this article, the design of complementary ECDs with two reversible redox electrodes operating in series is presented by combining the electrochemical and optical properties of these two electrodes, and the required parameters in the design equations are evaluated from the fabricated cell.
TL;DR: In this paper, a target material for r.f.-sputtering thin-film deposition onto suitable substrates has been used, and the films obtained have been characterized before and after electrochemical lithium intercalation.
Abstract: Research studies on new materials have shown that cerium-vanadium mixed oxides have potential for use as counter-electrodes in electrochromic devices owing to the combination of the excellent stability and transparency of cerium oxides and the high ion-storage capacity of the vanadium oxides. Among them, cerium orthovanadate (CeVO 4 ) has shown its potentiality as an intercalation electrode of suitable structure into which ions can be inserted reversibly, thus balancing the ion-charge capacity required by WO 3 , which is the colouring electrode in electrochromic devices. In this work, cerium-vanadium stoichiometric oxides (CeO 2 -V 2 O 5 , 1:1 molar ratio) have been used as a target material for r.f.-sputtering thin-film deposition onto suitable substrates. The films obtained have been characterized before and after electrochemical lithium intercalation. Their XPS and x-ray-induced Auger electron spectroscopy spectra have been compared with those obtained with the standard precursor oxides and the results discussed also on the basis of literature data. In order to be able to observe the changes in chemical state and composition expected on film formation, a careful curve-fitting procedure has been used that allows the determination of the background structure and intrinsic satellites for each peak, as reported already in previous papers.
TL;DR: In this article, the authors summarize recent trends in the studies on nonaqueous proton conducting gel electrolytes and their relation to the type and concentration of polymer matrix, proton donor as well as the solvent used.
TL;DR: A review of electrochromics and polymer gels, especially from the perspective of the extensive patent literature on the subject, is given in this article, where several definitions are compared with regard to gels and solution-based electrochromic redox systems.
TL;DR: In this article, the suitability of tungsten trioxide as the ionic storage layer for all-solid inorganic electrochromic devices was investigated. But the authors focused on the optical properties of the thin films of nickel oxide.
TL;DR: In this paper, the color change of laminate devices was measured using spectrocolorimetric techniques and analyzed using Commission Internationale de l'Eclairage 1931 (x, y)-chromaticity coordinates.
Abstract: Electrochromic devices composed of laminated polymer layers, as the working electrode, and vanadium pentoxide, as the counter electrode, were prepared and evaluated. Three different laminate systems were investigated using various combinations of poly(3,4-ethylenedioxythiophene), poly(N-methylpyrrole), and polyaniline as the active electrochromes. The color change of the laminate devices was measured using spectrocolorimetric techniques and analyzed using Commission Internationale de l'Eclairage 1931 (x, y)-chromaticity coordinates. The device's observed colors in their fully doped and dedoped states are found to be linearly dependent on the color coordinates of the two individual polymers that comprise the laminate.
TL;DR: In this article, a six-layer electrochromic device of indium tin oxide (ITO)/NiOxHy/WO3/ZrP-electrolyte/W3/ITO was made by reactive dc magnetron sputtering and lamination.
Abstract: Six-layer electrochromic devices of indium tin oxide (ITO)/NiOxHy/WO3/ZrP-electrolyte/WO3/ITO were made by reactive dc magnetron sputtering and lamination. The WO3 layer between the acidic ZrP-based electrolyte and the NiOxHy layer served as optically passive protective layer. The optical inactivity of the protective layer could be understood from arguments based on electron density of states.
Patent•
21 Mar 2001TL;DR: In this article, a method of protecting an ion insertion material from the degradative effects of a liquid or gel-type electrolyte material by deposing a protective, solid ion conducting, electrically insulating, layer between the ion insertion layer and the liquid/gel-type electrode material was proposed.
Abstract: The invention provides a method of protecting an ion insertion material from the degradative effects of a liquid or gel-type electrolyte material by deposing a protective, solid ion conducting, electrically insulating, layer between the ion insertion layer and the liquid or gel-type electrolyte material. The invention further provides liquid or gel-type electrochemical cells having improved durability having a pair of electrodes, a pair of ion insertion layers sandwiched between the pair of electrodes, a pair of solid ion conducting layers sandwiched between the ion insertion layers, and a liquid or gel-type electrolyte material disposed between the solid ion conducting layers, where the solid ion conducting layer minimizes or prevents degradation of the faces of the ion insertion materials facing the liquid or gel-type electrode material. Electrochemical cells of this invention having increased durability include secondary lithium batteries and electrochromic devices.
TL;DR: In this article, a coupled bipyridinium-based dye system showing excellent daylight, long-term, and cycle stability is presented, and the coupled system showed a stable switching performance for more than 4000 h.
Abstract: A new coupled bipyridinium-based dye system showing excellent daylight, long term, and cycle stability is presented here. Cells with the coupled system show a stable switching performance for more than 4000 h. Deliberate matching of the counter anion/dye system with the solution allows compensation of the density change, which quenches the color segregation in EC dye systems. The figure shows an EC cell containing the electrochromic dye system PpVBPhP as described in this paper.
TL;DR: In this article, the most important examples from the major classes of electrochromic materials are highlighted, including car mirrors, windows and sun-roofs of cars, windows of buildings, displays, printing, and frozen-food monitoring.
Abstract: Many inorganic and organic materials exhibit redox states with distinct electronic (UV-vis) absorption bands. When the switching of redox states generates new or different visible region bands, the material is electrochromic. Electrochromic materials are currently attracting much interest in academia and industry for both their fascinating spectroelectrochemical properties and their commercial applications. In this review some of the most important examples from the major classes of electrochromic materials are highlighted. Examples of their use in both prototype and commercial electrochromic devices are illustrated including car mirrors, windows and sun-roofs of cars, windows of buildings, displays (see Figure), printing, and frozen-food monitoring.
TL;DR: In this paper, the temperature dependence of the charge capacity and associated reflectance modulation for W oxide films deposited in the temperature range 100-350°C was investigated for their use in infrared reflectance modulating electrochromic devices.
TL;DR: In this article, the physical properties of In2O3-ZnO pulsed laser deposited thin films were investigated and the authors found that the electrical properties of the films are greatly governed by their microstructure, which evolves from granular to fiber and to columnar textures.
TL;DR: In this paper, the authors discuss the deposition and preliminary characterisation of the solid-state electrolyte of a symmetric GdMg device tested in a hydrogen gas atmosphere.
TL;DR: In this paper, a study of electrochromic (EC) devices based on WO 3 thin films with textured surfaces was presented, which were used for the fabrication of EC devices of the configuration: K-glass/WO 3 /1 M LiClO 4 in PC/K-glass.
TL;DR: In this article, an overview of an in situ method of electrochromic polymer characterization based on the CIE system of colorimetry is presented, as illustrated here for PBuDOP (poly(3,4-butylenedioxypyrrole)), colorimetric analysis allows for precise understanding of color change and the accessible color states of an electro chromic polymer.
TL;DR: In this paper, single and double layers of tungsten oxide and vanadium oxide thin films have been deposited on In2O3:SnO2 (ITO) glass using the pulsed laser deposition (PLD) technique at a substrate heating temperature of 200 degreesC and in rich oxygen pressure.
TL;DR: In this paper, a hydrogen-based device consisting of a GdMgH5 electrochromic layer, a ZrO2Hx electrolyte and a WO3 counter electrode was made.
Patent•
31 Dec 2001TL;DR: In this article, a polymer electrolyte comprising amine groups dispersed throughout the polymer backbone, including various poly(ethylenimine)-based polymers, which enable ionic movement for use in various applications, including for example batteries, fuel cells, sensors, supercapacitors and electrochromic devices.
Abstract: The present invention is directed to a polymer electrolyte (15) comprising amine groups dispersed throughout the polymer backbone, including various poly(ethylenimine)-based polymers, which enable ionic movement for use in various applications, including for example batteries, fuel cells, sensors, supercapacitors and electrochromic devices. The present invention is further directed to a method for preparing such polymer electrolytes.
TL;DR: In this paper, thin films of mixed oxides of Nb2O5-TiO2 with molar ratio Nb/Ti = 3, have been prepared by sol-gel sonocatalytic method.
Abstract: Thin films of mixed oxides of Nb2O5-TiO2 with molar ratio Nb/Ti = 3, have been prepared by sol-gel sonocatalytic method. The precursor sols consist of a mixture of niobium salt NbCl5, titanium alkoxide Ti(OPri)4, isopropanol and acetic acid. After addition of all components the mixture was sonicated. The films were deposited by dip-coating technique on ITO-Asahi Glass and then submitted to a final heat treatment at 560°C during 3 h in atmosphere of oxygen. The electrochromic properties of the films were investigated using in situ spectroelectrochemical method. The films exhibit a blue-gray coloration under lithium ions insertion with a reversible variation of the transmittance in the visible and near infrared range between 90% and 20%. The xerogels of Nb2O5-TiO2 also were characterized by X-ray diffraction, thermal analysis (DTA/TGA) and IR measurements. The morphology of the films was observed by scanning electron microscopy (SEM) and the topography by atomic force microscopy (AFM). These films appear suitable for architectural applications, where a minimum performance in depth color is required.