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Showing papers on "Electrochromism published in 1984"


Journal ArticleDOI
TL;DR: Revetement en couche mince d'electrodes en platine, par oxydation galvanostatique d'aniline a 0,1m Acm −2 en solutions 2M d'acide chlorhydrique contenant 1M aniline

625 citations


Journal ArticleDOI
TL;DR: In this article, inorganic and organic electrochromic materials are discussed in the context of developing a film-based optical shutter for a window application, which allows regulation of conductive and radiative heat transfer rates, with variable optical attenuation.

548 citations


Journal ArticleDOI
TL;DR: In this paper, the electrochromic reactions of polyaniline film-coated electrodes were investigated in acid solutions in the potential range between −0.2 V and 0.6 V vs. SCE, where the color of the film changes from transparent yellow to green depending on the potential.

384 citations


Journal ArticleDOI
TL;DR: In this article, a transparent electrochromic device was made by coating conducting glass with reactively evaporated tungsten oxide films and letting these specimens form the working electrode in an electrochemical cell containing an electrolyte of LiClO4 + propylene carbonate.

146 citations


Journal ArticleDOI
TL;DR: In this article, electropolymerized polyazulene and polythiophene have been found to be surprisingly insensitive to common solvents and temperature, allowing current densities of 2 mA/cm2 at opencircuit voltages of 2.3V.
Abstract: Electroactive and electrochromic films of electropolymerized polyazulene and polythiophene have been found to be surprisingly insensitive to common solvents and temperature. As electrodes in all‐organic batteries these thin polymeric films allow current densities of 2 mA/cm2 at open‐circuit voltages of 2.3V. The electrochromic properties suggest application in electro‐optical displays.

131 citations


Journal ArticleDOI
TL;DR: Amorphous tungsten trioxide films, investigated by the Raman scattering method, are shown to be composed of a spatial network of tightly bound (WO6)n·mH2O clusters with a large number of terminal oxygen W=O and W-O-W bonds between clusters as mentioned in this paper.

119 citations


Journal ArticleDOI
TL;DR: In this paper, a quantitative theory for the optical properties of crystalline electrochromic materials is introduced, based on the double injection model and including ionized impurity scattering of free electrons.
Abstract: A quantitative theory for the optical properties of crystalline electrochromic materials is introduced. It is based on the double injection model and includes ionized impurity scattering of free electrons. Solar and luminous properties are evaluated versus electron density for doped WO3 films. Our results point to the possibility of creating efficient ‘‘smart windows’’ with dynamic control of the inflow of radiant energy.

110 citations


Journal ArticleDOI
TL;DR: The physical and electrochemichromic properties of amorphous and crystalline tungsten oxide films prepared by thermal evaporation of WO3 powder under a reducing atmosphere have been investigated.
Abstract: The physical and electrochemichromic properties of the amorphous and crystalline tungsten oxide films prepared by thermal evaporation of WO3 powder under a reducing atmosphere have been investigated. The oxide films with 850–24 500 A thick were deposited on the substrates maintained at a temperature ranging from 50 to 500 °C under a vacuum below 1×10−5 Torr. Properties of the oxide films formed depend considerably on the deposition temperature. The as‐prepared oxide films formed at a temperature higher than 400 °C have a resistivity of 10−3−10 Ω cm, and are blue colored, and mainly composed of crystalline WO3. The oxide films formed at a temperature lower than 350 °C have a resistivity of 105–109 Ω cm, and are transparent and amorphous. Both of the amorphous and crystalline oxide films have good electrochemichromic properties. From x‐ray analysis, the crystalline WO3 thick films were found to change to hydrogen tungsten bronze films with a chemical composition of H0.33WO3 during electrochemical coloration...

110 citations


Journal ArticleDOI
TL;DR: In this article, the change in film color which occurs in the redox reaction of the film was investigated in detail as a function of electrode potential and the charge consumed in the reaction.
Abstract: Polypyrrole films prepared by anodic polymerization of pyrrole on Pt or SnO2-coated glass show redox behavior in aqueous electrolyte solutions containing a supporting electrolyte alone. Transfer of electrolyte anions into and from the film is involved in the redox reaction similarly with acetonitrile solutions already reported. Insertion of divalent anions into the film occurs in two steps but that of monovalent anions in one step, as judged from corresponding cyclic voltammograms. The change in film color which occurs in the redox reaction of the film was investigated in detail as a function of electrode potential and the charge consumed in the redox reaction. Polypyrrole is a promising material for electrochromic display devices.

79 citations


Patent
31 Aug 1984
TL;DR: An electronic display device having a polyaniline film coated on a transparent electrode has been described in this paper, which can display at least three distinct reproducible color changes and has electrochromic properties.
Abstract: An electronic display device having a polyaniline film coated on a transparent electrode. The film has electrochromic properties and will display at least three distinct reproducible color changes.

77 citations


Journal ArticleDOI
TL;DR: It is concluded that the slow electrochromic phase probably does not arise from a mechanism involving a turnover of cytochrome b6, and it is suggested that it may arises from a redox-linked H+ pump involving the high potential iron-sulfur protein.

Proceedings ArticleDOI
02 Nov 1984
TL;DR: In this paper, the authors introduce electrochromic coatings for use on "smart windows" with dynamic control of radiant energy, and investigate crystalline films by computations aimed at assessing performance limits, and amorphous films with regard to practrical performance in contact with liquid or solid electrolytes.
Abstract: We introduce electrochromic coatings for use on "smart windows" with dynamic control of radiant energy. Applications, operating principles, materials options, and device configuration are briefly reviewed. We then focus on electrochromic WO3 and investigate crystalline films by computations aimed at assessing performance limits, and amorphous films with regard to practrical performance in contact with liquid or solid electrolytes. It appears that there are several approaches to achieving a gradual and reversible modulation of the radiative performance in a manner consistent with uses on "smart windows".

Journal ArticleDOI
TL;DR: In this article, the modulation de la reflectivite est determinee par la densite et la diffusion des electrons libres de Drude, a.k.a., the densite and diffusion of electrons.
Abstract: Mesure des constantes optiques par ellipsometrie, a 940, 633 et 546 mm, sur des couches minces preparees par pulverisation haute frequence. Validite du modele des electrons libres de Drude: la modulation de la reflectivite est determinee par la densite et la diffusion des electrons libres

Journal ArticleDOI
TL;DR: In this article, after dark adaptation of oxygen-evolving PS II complexes, oscillatory absorption changes (stable > 0.5 s) with a periodicity of 4 were detected at 514 nm and correlated with the four oxidation states of the water-splitting enzyme system S. Supposing that the changes are due to electrochromic shifts, they might indicate a positive surplus charge in states S2 and S3.

Journal ArticleDOI
TL;DR: In this paper, the authors investigated the transparency-time relation of a mixed solution of n-heptyl viologen dibromide (HV), Fe(CN) 6 PsyNet 4−¯¯¯¯ and NaH2PO2 or KBr were investigated by cyclic voltammetry and the transparency time relation.
Abstract: Electrochromic properties of the mixed solution of n-heptyl viologen dibromide (HV), Fe(CN) 6 4− and NaH2PO2 or KBr were investigated by cyclic voltammetry and the transparency-time relation. When Fe(CN) 6 4− is added to a HV solution the mixture colours violet without inputting any voltage. However, the colour fades gradually by further addition of NaH2PO2, and the transparency of the mixture increases with addition of larger amounts of NaH2PO2. The same effect was observed by addition of KBr to the HV-Fe(CN) 6 4− solution. The input voltage required for the electrochromism of HV is lowered considerably by addition of Fe(CN) 6 4− , when NaH2PO2 or KBr plays a role in controlling the colouringerasing phenomena. The HV-Fe(CN) 6 4− -KBr system showed some HV ‘residue’ in the cyclic voltammogram on an indium-tin oxide (ITO) electrode, while no such HV ‘residue’ was observed in the HV-Fe(CN) 6 4− -NaH2PO2 system. The HV-Fe(CN) 6 4− -NaH2PO2 system is superior in colouring-erasing reproducibility and in response time to the HV solution or the HV-Fe(CN) 6 4− system.

Journal ArticleDOI
TL;DR: In this article, a range of diquaternary salts of 4,4′-bipyridine and 3,8-phenanthroline were prepared and subsequently screened using electrochemical and spectroscopic techniques.
Abstract: A range of diquaternary salts of 4,4′-bipyridine and 3,8-phenanthroline were prepared and subsequently screened using electrochemical and spectroscopic techniques. It was determined that the stability of the radical film deposited on cathodic reduction of aqueous solutions of these salts may be strongly influenced by symmetry, steric, and electronic factors. From this basis, it was possible to design a viologen, 1,1′-bis-(2-methylbenzyl)-2-methyl-4,4′-bipyridinium dibromide (9), having electrochromic properties for electronic display applications superior to those already in existence. A radical film of mixed composition was found to be less susceptible to ageing effects than films generated from the individual dicationic salts.

Journal ArticleDOI
TL;DR: The influence of substrate, thermal treatment and coloration-bleaching cycles on the structure of WO3 thin films used in electrochromic devices has been investigated by Raman microscopy.

Patent
11 Dec 1984
TL;DR: In this article, a composite ion exchange film is applied to the ECD element by laminating the plural numbers of the ion exchange films having the same electric charge and different sorts of ion exchange groups to the element.
Abstract: PURPOSE: To maintain a response rate for long periods and to make coloring and discoloring clear by applying a composite ion exchange film obtd. by laminating the plural numbers of the ion exchange films having the same electric charge and different sorts of the ion exchange groups, to the element. CONSTITUTION: The transparent conductive film, the electrochromic film, the ion exchange film and the counter electrode are laminated on the substrate in order, to form the ECD element. The ion exchange film which is prepared by laminating the plural numbers of the ion exchange films having the same electric charge and the different ion exchange groups, is used. The coloring and the discoloring of the titled element are controlled by the hydrogen ion, and the response rate of the titled element is changed by changing the amount and the mobility rate of the hydrogen ion. By combining the plural numbers of the ion exchange films having different degrees of dissociation which influences to the ion transfer rate, the merit of each ion exchange film is exhibited thereby improving each performances of the response rate, the working life, the power consumption and the contrast ratio of the titled element, and balancing each performances. COPYRIGHT: (C)1986,JPO&Japio

Patent
31 Jul 1984
TL;DR: In this article, the color formers are prepared by the interaction of the corresponding 5-(N-R1 -amino)-9-(NR2 -N-r3 -aminosinium halide) or 9-(n-R2-n-r-3-amino)phenoxazin-5-one with a reducing agent and subsequently interacting the leuco compound with at least two molecular proportions of an acylating agent.
Abstract: 5-[N-(RCO)-N-R1 -amino] or (RCOO)-9-(N-R2 -N-R3 -amino)-12-(RCO)benzo[a]phenoxazines useful as color formers, particularly in electrochromic recording systems, are prepared by the interaction of the corresponding 5-(N-R1 -amino)-9-(N-R2 -N-R3 -amino)benzo[a]phenoxazinium halide or 9-(N-R2 -N-R3 -amino)benzo[a]phenoxazin-5-one with a reducing agent to obtain the corresponding leuco compound and subsequently interacting the leuco compound with at least two molecular proportions of an acylating agent.

Journal ArticleDOI
TL;DR: In this article, a large area electrochromic structure with the generalized geometry TEC, EC1, EC2, EC3, EC4, EC5, EC6, EC7, EC8, EC9, EC10, EC11, EC12, EC13, EC14, EC15, EC16, EC17, EC18, EC19, EC20, EC21, EC22, EC23, EC24, EC25, EC26, EC27, EC28, EC29, EC30, EC31, EC32, EC

Journal ArticleDOI
TL;DR: In this article, a variety of optical coatings are discussed in the context of solar energy utilization, focusing on the materials' limitations and on use of lesser-known optical coating and materials.
Abstract: A variety of optical coatings are discussed in the context of solar energy utilization. Well-known coatings such as transparent conductors (heat mirrors), selective absorbers, and reflective films are surveyed briefly. Emphasis is placed on the materials' limitations and on use of lesser-known optical coatings and materials. Physical and optical properties are detailed for protective antireflection films, cold mirrors, fluorescent concentrator materials, radiative cooling surfaces, and optical switching films including electrochromic, thermochromic, photochromic, and liquid crystal types. For many of these materials, research has only recently been considered, so various design and durability issues need to be addressed.

Journal ArticleDOI
TL;DR: In this paper, the electrochromic response of tungsten oxide films deposited in a pure oxygen atmosphere was found to show the best value at an O/W ratio of 2.5.
Abstract: The electrochromic response of tungsten oxide films deposited in a pure oxygen atmosphere was found to show the best value at an O/W ratio of 2.5. When argon was introduced into the atmosphere, the response became faster, as the total pressure increased. However, the best response values, for films deposited in an atmosphere containing oxygen, were usually attained at a fixed partial pressure of oxygen. The factors determining the electrochromic response in a cell utilizing atmospheric evaporated tungsten oxide films (AETOF) were analyzed, and the dependence of the film formation conditions on these factors was investigated.

Journal ArticleDOI
TL;DR: In this paper, a new method of formation of electrochromic MoO3 thin oxide film on electric conducting glass (ITO glass) was investigated for use in place of the conventional vacuum evaporation method.
Abstract: A new method of formation of electrochromic MoO3 thin oxide film on electric conducting glass (ITO glass) has been investigated for use in place of the conventional vacuum evaporation method. The ITO glass was cathodically electrolyzed in an aqueous solution of 0.007 mol/l lithium molybdate at a constant current density of ca. 3 A/m2 at 25°C. Blue, conductive and adhesive oxide film was obtained. Cycles of the coloration and bleach were repeated in the propylene carbonate solution of lithium perchlorate. A good reversibility was obtained.

Journal ArticleDOI
TL;DR: In this article, the authors investigated the electro-optical behavior of solid-state electrochromic devices (ECD) by analysing their current pulses and the linear sweeping of the bias voltage.

Patent
21 May 1984
TL;DR: In this article, the authors proposed to obtain an electrochromic display element with a decreased change in a writing characteristic with time by interposing a solid intermediate layer between a display body and a counter electrode.
Abstract: PURPOSE:To obtain an electrochromic display element with a decreased change in a writing characteristic with time by interposing a solid intermediate layer between a display body and a counter electrode, and interposing a fluorocomplex between the display body and the solid intermediate layer CONSTITUTION:A display body 3 is constituted of a display body of thin film of for example, tungsten oxide For example, a solid electrolyte of lithium nitride is deposited by evaporation as an intermediate layer 4 after vapor deposition of, for example, lithium hexafluoroaluminate as a fluorocomplex 11 on the body 3 and further, for example, tungsten oxide is deposited by evaporation as a counter electrode 5 thereon and then gold is deposited by evaporation as a lead 6 A back substrate 7 consisting of glass is unitited to the transparent substrate 1 by an adhesive agent 8 consisting of an epoxy resin The complex 11 has the effect of preventing the crystallization of the amorphous display body 3 Said body 3 consists of >=1 kind selected from molybdenum oxide and niobium oxide in addition to the above-described tungsten oxide or the transition metal oxide consisting essentially thereof The complex 11 consists of the complex of >=1 kind selected from the group of lithium hexafluoroaluminate, lithium hexafluorosilicate, etc

Patent
11 Sep 1984
TL;DR: In this article, the color-forming substances of spiro[isoindole-xanthene]-3, xanthene-4, and spiro [phthalazine]-4 are used as colorforming substances, particularly in electrochromic recording systems.
Abstract: This invention relates to spiro[isoindole-xanthene]-3- ones, spiro[phthalazine-xanthene]-4-ones, and xanthene-3- ones useful as color-forming substances, particularly in electrochromic recording systems, which are prepared by the interaction of a fluoran with a substituted or unsubstituted hydrazine.


Patent
21 Dec 1984
TL;DR: In this article, a solid-state transition metal oxide device comprising a plurality of layers having a predisposed orientation including an electrochromic oxide layer is described, and the coloration action is adapted to sweep or dynamically extend across the length of the oxide layer.
Abstract: LOW VOLTAGE SOLID-STATE LATERALCOLORATION ELECTROCHROMIC DEVICE ABSTRACT A solid-state transition metal oxide device (40) comprising plurality of layers having a predisposed orientation including an electrochromic oxide layer (46). Conductive material including an anode contact (42) and a cathode contact (52) is secured to the device (40). Coloration is actuated within the electrochromic oxide layer (46) after the application of a predetermined potential between the contacts. The coloration action as adapted to sweep or dynamically extend across the length of the electrochromic oxide layer (46).

Journal ArticleDOI
TL;DR: In this paper, a layer structured crystal β-zirconium nitride chloride ZrNCl has been found to form a new lithium intercalate, which occurs either by the n-butyl lithium technique or by electrochemical redox reactions.
Abstract: A layer structured crystal β-zirconium nitride chloride ZrNCl has been found to form a new lithium intercalate. The intercalation occurs either by the n-butyl lithium technique or by electrochemical redox reactions. The layer crystal exhibits electrochromic behavior on intercalation-deintercalation of the lithium.

Journal ArticleDOI
TL;DR: In this paper, the color change of Er-diphthalocyanine complex (ErH(Pc)2) film was investigated with (Glass/ITO/ErH2+LiF/LiF+CaCl2/Ag) solid cells.
Abstract: Electrochromism of Er-diphthalocyanine complex (ErH(Pc)2) film was investigated with (Glass/ITO/ErH(Pc)2+LiF/LiF+CaCl2/Ag) solid cells. The fast change of color from green to purple-red was observed when positive voltages of about 2 V were applied to the ITO electrode, while negative voltages of about -2 V resulted in the change of color to blue-black. The former oxidation process was preceded by the migration of chlorine anions of CaCl2 in the dielectric layer. However, the mechanism of the latter reduction process remains vague.