Showing papers on "Electrochromism published in 2012"
TL;DR: Polyimides rank among the most heat-resistant polymers and are widely used in high temperature plastics, adhesives, dielectrics, photoresists, nonlinear optical materials, membrane materials for separation, and Langmuir-Blodgett (LB) films, among others as mentioned in this paper.
1,534 citations
TL;DR: This article has reviewed several examples from research work as well as from other researchers' work, describing the recent advancements on the materials that exhibit visible electrochromism and polymer electrolytes for electrochromic devices.
Abstract: Electrochromic (EC) materials and polymer electrolytes are the most imperative and active components in an electrochromic device (ECD). EC materials are able to reversibly change their light absorption properties in a certain wavelength range via redox reactions stimulated by low direct current (dc) potentials of the order of a fraction of volts to a few volts. The redox switching may result in a change in color of the EC materials owing to the generation of new or changes in absorption band in visible region, infrared or even microwave region. In ECDs the electrochromic layers need to be incorporated with supportive components such as electrical contacts and ion conducting electrolytes. The electrolytes play an indispensable role as the prime ionic conduction medium between the electrodes of the EC materials. The expected applications of the electrochromism in numerous fields such as reflective-type display and smart windows/mirrors make these materials of prime importance. In this article we have reviewed several examples from our research work as well as from other researchers’ work, describing the recent advancements on the materials that exhibit visible electrochromism and polymer electrolytes for electrochromic devices. The first part of the review is centered on nanostructured inorganic and conjugated polymer-based organic-inorganic hybrid EC materials. The emphasis has been to correlate the structures, morphologies and interfacial interactions of the EC materials to their electronic and ionic properties that influence the EC properties with unique advantages. The second part illustrates the perspectives of polymer electrolytes in electrochromic applications with emphasis on poly (ethylene oxide) (PEO), poly (methyl methacrylate) (PMMA) and polyvinylidene difluoride (PVDF) based polymer electrolytes. The requirements and approaches to optimize the formulation of electrolytes for feasible electrochromic devices have been delineated.
648 citations
TL;DR: In this article, the authors discuss basic electrochromic device designs, useful oxide materials and their nanostructures, and elements of a theoretical description of the electro chromic phenomenon.
388 citations
TL;DR: The first successful application of an ordered bicontinuous double-gyroid vanadium pentoxide network in an electrochromic supercapacitor is reported, which is ideal for fast and efficient lithium ion intercalation/extraction and faradaic surface reactions, which are essential for high energy and high power density electrochemical energy storage devices.
Abstract: We report the first successful application of an ordered bicontinuous double-gyroid vanadium pentoxide network in an electrochromic supercapacitor. The freestanding vanadia network was fabricated by electrodeposition into a voided block copolymer template that had self-assembled into the double-gyroid morphology. The highly ordered structure with 11.0 nm wide struts and a high specific surface to bulk volume ratio of 161.4 μm–1 is ideal for fast and efficient lithium ion intercalation/extraction and faradaic surface reactions, which are essential for high energy and high power density electrochemical energy storage devices. Supercapacitors made from such gyroid-structured vanadia electrodes exhibit a high specific capacitance of 155 F g–1 and show a strong electrochromic color change from green/gray to yellow, indicating the capacitor’s charge condition. The nanostructuring approach and utilizing an electrode material that has intrinsic electrochemical color-change properties are concepts that can be read...
342 citations
TL;DR: In this paper, an integrated multifunctional flexible device called the Energy Storage Smart Window (ESS window) was designed and fabricated, which comprises an integrated supercapacitor and electrochromism function in one flexible device using ordered polyaniline nanowire arrays as electrodes.
Abstract: In this paper, a new integrated multifunctional flexible device called the Energy Storage Smart Window (ESS window) was designed and fabricated. The proposed ESS window comprises an integrated supercapacitor and electrochromism function in one flexible device using ordered polyaniline nanowire arrays as electrodes. The ESS window showed high areal capacitance and high stability as a supercapacitor, and in situ optical measurements proved its electrochromic function. Furthermore, the ESS window can be integrated with a conventional solar cell to form a smart device system, which can simultaneously harvest, store, and use renewable energy efficiently.
322 citations
TL;DR: Coating copper nanowires to a ratio of 2:1 Cu:Ni gave them a neutral gray color, making them more suitable for use in displays and electrochromic windows, and make cupronickel nanoweires a promising alternative for the sustainable, efficient production of transparent conductors.
Abstract: Nanowires of copper can be coated from liquids to create flexible, transparent conducting films that can potentially replace the dominant transparent conductor, indium tin oxide, in displays, solar cells, organic light-emitting diodes, and electrochromic windows. One issue with these nanowire films is that copper is prone to oxidation. It was hypothesized that the resistance to oxidation could be improved by coating copper nanowires with nickel. This work demonstrates a method for synthesizing copper nanowires with nickel shells as well as the properties of cupronickel nanowires in transparent conducting films. Time- and temperature-dependent sheet resistance measurements indicate that the sheet resistance of copper and silver nanowire films will double after 3 and 36 months at room temperature, respectively. In contrast, the sheet resistance of cupronickel nanowires containing 20 mol % nickel will double in about 400 years. Coating copper nanowires to a ratio of 2:1 Cu:Ni gave them a neutral gray color, making them more suitable for use in displays and electrochromic windows. These properties, and the fact that copper and nickel are 1000 times more abundant than indium or silver, make cupronickel nanowires a promising alternative for the sustainable, efficient production of transparent conductors.
306 citations
TL;DR: The main conceptual tools needed to address the study of the electrochemical properties of TiO(2) nanostructured electrodes are reviewed, as well as the electrochemistry methods to prepare and modify them.
Abstract: Several of the multiple applications of titanium dioxide nanomaterials are directly related to the introduction or generation of charge carriers in the oxide. Thus, electrochemistry plays a central role in the understanding of the factors that must be controlled for the optimization of the material for each application. Herein, the main conceptual tools needed to address the study of the electrochemical properties of TiO(2) nanostructured electrodes are reviewed, as well as the electrochemical methods to prepare and modify them. Particular attention is paid to the dark electrochemical response of these nanomaterials and its direct connection with the TiO(2) electronic structure, interfacial area and grain boundary density. The physical bases for the generation of currents under illumination are also presented. Emphasis is placed on the fact that the kinetics of charge-carrier transfer to solution determines the sign and value of the photocurrent. Furthermore, methods for extracting kinetic information from open-circuit potential and photocurrent measurements are briefly presented. Some aspects of the combination of electrochemical and spectroscopic measurements are also dealt with. Finally, some of the applications of TiO(2) nanostructured samples derived from their electrochemical properties are concisely reviewed. Particular attention is paid to photocatalytic processes and, to a lesser extent, to photosynthetic reactions as well as to applications related to energy from the aspects of both saving (electrochromic layers) and accumulation (batteries). The use of TiO(2) nanomaterials in solar cells is not covered, as a number of reviews have been published addressing this issue.
242 citations
TL;DR: A battery-powered, microelectrochemical sensing platform that reports its output using an electrochromic display and the applicability of the device to point-of-care sensing is demonstrated by qualitative detection of 0.1 mM glucose and H(2)O( 2) in artificial urine samples.
Abstract: We report a battery-powered, microelectrochemical sensing platform that reports its output using an electrochromic display. The platform is fabricated based on paper fluidics and uses a Prussian blue spot electrodeposited on an indium-doped tin oxide thin film as the electrochromic indicator. The integrated metal/air battery powers both the electrochemical sensor and the electrochromic read-out, which are in electrical contact via a paper reservoir. The sample activates the battery and the presence of analyte in the sample initiates the color change of the Prussian blue spot. The entire system is assembled on the lab bench, without the need for cleanroom facilities. The applicability of the device to point-of-care sensing is demonstrated by qualitative detection of 0.1 mM glucose and H2O2 in artificial urine samples.
223 citations
TL;DR: In this article, the authors present the most important and common trends regarding polymer synthesis from the point of view of the introduction of triarylamine moiety into polymer chains and demonstrate how the polymer structures influence their properties, leading them to be suitable for optoelectronic device construction.
208 citations
TL;DR: In this article, a PANI/tungsten oxide (WO3) nanocomposite was fabricated by electropolymerization of aniline monomers onto indium tin oxide (ITO) glass slides, which were prepared by spin coating technique and followed by annealing at 500 °C for 2 h.
Abstract: Polyaniline (PANI)/tungsten oxide (WO3) nanocomposite films were fabricated by electropolymerization of aniline monomers onto WO3 coated indium tin oxide (ITO) glass slides, which were prepared by spin coating technique and followed by annealing at 500 °C for 2 h. The morphology and crystalline structure of the composite films were studied using Fourier transform infrared (FT-IR) spectroscopy, atomic force microscopy (AFM), X-ray diffraction (XRD), and transmission electron microscopy (TEM). The results confirm chemical interactions between the polymer matrix and the WO3 particles and reveal a well crystallized PANI/WO3 nanocomposite structure. The optical properties and electrochemical capacitive behaviors of the composite films for electrochromic (EC) and energy storage devices applications were investigated using spectroelectrochemistry (SEC), cyclic voltammetry (CV) and galvanostatic charge–discharge measurements. The composite films show dual electrochromism at both positive and negative potentials a...
208 citations
TL;DR: The major surface oxide species observed, reversible redox transitions of the surface oxides, pseudocapacitance and catalytic reduction are discussed along with carefully conducted experimental results on a typical molybdenum glass back contact employed in CIGS-based solar cells.
Abstract: The electrochemical behaviors of molybdenum and its oxides, both in bulk and thin film dimensions, are critical because of their widespread applications in steels, electrocatalysts, electrochromic materials, batteries, sensors, and solar cells. An important area of current interest is electrodeposited CIGS-based solar cells where a molybdenum/glass electrode forms the back contact. Surprisingly, the basic electrochemistry of molybdenum and its oxides has not been reviewed with due attention. In this Review, we assess the scattered information. The potential and pH dependent active, passive, and transpassive behaviors of molybdenum in aqueous media are explained. The major surface oxide species observed, reversible redox transitions of the surface oxides, pseudocapacitance and catalytic reduction are discussed along with carefully conducted experimental results on a typical molybdenum glass back contact employed in CIGS-based solar cells. The applications of molybdenum oxides and the electrodeposition of molybdenum are briefly reviewed.
TL;DR: Dual functionalities of antireflective and electrochromic properties-based anatase TiO(2) nanowire devices with a high-porosity cross-linked geometry directly grown onto transparent conductive glass was achieved for the first time through a simple one-step hydrothermal process under mild alkali conditions.
Abstract: Dual functionalities of antireflective and electrochromic properties-based anatase TiO2 nanowire devices with a high-porosity cross-linked geometry directly grown onto transparent conductive glass was achieved for the first time through a simple one-step hydrothermal process under mild alkali conditions. Devices fashioned from these TiO2 nanowires were found to display enhanced optical transparency in the visible range, better color contrast, and faster color-switching time in comparison to devices made from nanoparticles. These improvements can be attributed to the low refractive index and high porosity of the TiO2 nanowires and their larger accessible surface area for Li+ intercalation and deintercalation, leading to enhanced capabilities for transparent electrochromic smart windows.
TL;DR: In this article, a 3D crystalline tungsten trioxide (WO(3)) nanoporous network, directly grown on a transparent conductive oxide (TCO) substrate, is shown to be a suitable working electrode material for high performance electrochromic devices.
Abstract: We demonstrate that a three dimensional (3D) crystalline tungsten trioxide (WO(3)) nanoporous network, directly grown on a transparent conductive oxide (TCO) substrate, is a suitable working electrode material for high performance electrochromic devices. This nanostructure, with achievable thicknesses of up to 2 μm, is prepared at room temperature by the electrochemical anodization of a RF-sputtered tungsten film deposited on a fluoride doped tin oxide (FTO) conductive glass, under low applied anodic voltages and mild chemical dissolution conditions. For the crystalline nanoporous network with thicknesses ranging from 0.6 to 1 μm, impressive coloration efficiencies of up to 141.5 cm(2) C(-1) are achieved by applying a low coloration voltage of -0.25 V. It is also observed that there is no significant degradation of the electrochromic properties of the porous film after 2000 continuous coloration-bleaching cycles. The remarkable electrochromic characteristics of this crystalline and nanoporous WO(3) are mainly ascribed to the combination of a large surface area, facilitating increased intercalation of protons, as well as excellent continuous and directional paths for charge transfer and proton migration in the highly crystalline material.
TL;DR: Enhanced ion intercalation into the gyroid morphology can be extended to other transition-metal oxides and is therefore promising for lithium ion batteries, supercapacitors, and sensors.
Abstract: Manufacturing V(2)O(5) in a 3D periodic highly interconnected gyroid structure on the 10 nm length scale is shown to lead to a significant electrochromic performance enhancement. The structured devices surpass previous inorganic electrochromic materials in all relevant parameters: the switching speed, coloration contrast, and composite coloration efficiency. In particular, the 85 ms switching speed lies within a factor of two of video rate. Enhanced ion intercalation into the gyroid morphology can be extended to other transition-metal oxides and is therefore promising for lithium ion batteries, supercapacitors, and sensors.
TL;DR: The enhancement of electrochromic performances are attributed to the reinforcement of the electrochemical activity of the RGO sheets and the greater amount of open space in the porous hybrid film which allows the electrolyte to penetrate and shorten the proton diffusion paths within the bulk of NiO.
Abstract: A porous NiO/RGO hybrid film is prepared by the combination of electrophoretic deposition and chemical-bath deposition. The porous hybrid film exhibits a noticeable electrochromism with reversible color changes from transparent to dark brown, and shows high coloration efficiency (76 cm2 C−1), fast switching speed (7.2 s and 6.7 s) and better cycling performance compared with the porous NiO thin film. The enhancement of electrochromic performances are attributed to the reinforcement of the electrochemical activity of the RGO sheets and the greater amount of open space in the porous hybrid film which allows the electrolyte to penetrate and shorten the proton diffusion paths within the bulk of NiO.
TL;DR: Tungsten oxide nanoparticles synthesized via a sol-gel route using metallic tungsten as precursor, and were printed on a flexible electrode using inkjet printing in order to build solid-state electrochromic cells had a good cycling stability and a cyclability up to more than 50,000 cycles with a degradation of 25%.
Abstract: Tungsten oxide nanoparticles were synthesized via a sol-gel route using metallic tungsten as precursor, and were printed on a flexible electrode using inkjet printing in order to build solid-state electrochromic cells. Several spectroscopic techniques were used to characterize and compare tungsten oxide particles obtained from different origins. FTIR, Raman and X-ray diffraction spectroscopic measurements showed that the sol-gel synthesis described here produces nanoparticles mainly in an amorphous state with hexagonal crystalline domains and allowed the analysis of the hydration extent of those nanoparticles. The size was measured combining dynamic light scattering, sedimentation, and microscopic techniques (AFM), showing a consistent size of about 200 nm. The tungsten oxide nanoparticles were used to produce an ink formulation for application in inkjet printing. Solid-state electrochromic devices were assembled at room temperature, without sintering the tungsten oxide printed films, showing excellent contrast between on/off states. Electrochemical characterization of those films is described using cyclic voltammetry. The devices were then tested through spectroelectrochemistry by Visible/NIR absorption spectroscopy (400-2200 nm range), showing a dual spectroscopic response depending on the applied voltage. This phenomenon is attributed to the presence of two different crystalline states in accordance with results obtained from the spectroscopic characterization of the nanoparticles. The electrochromic cells had a good cycling stability showing high reversibility and a cyclability up to more than 50,000 cycles with a degradation of 25%.
TL;DR: In this article, a pulsed laser deposition (PLD) method was used to enhance the electrochromic properties of anodically colored NiO thin films by growing them on FTO/glass substrates.
TL;DR: In this article, a poly(3,4-ethylenedioxythiophene) chemically doped with poly(styrene sulfonic acid) (PEDOT:PSS) is used as conductive and transparent coating in several important electr...
TL;DR: In this article, a self-powered electrochromic system driven by a nanogenerator (NG) is demonstrated. But the performance of the system was limited to 10 seconds and 58.7 cm2 C−1, respectively.
Abstract: Electrochromic (EC) devices are capable of reversibly changing optical properties upon charge injection and extraction driven by an externally applied voltage. A nanogenerator (NG) is a device that converts mechanical energy into electricity. This paper demonstrates a self-powered EC device driven by an NG. An average visible optical modulation (ΔTvis) as large as 15.3% was obtained, with electrochromic response time (ERT) and coloration efficiency (CE) of 10 seconds and 58.7 cm2 C−1, respectively. Such a performance is comparable to an EC when powered by a hardwired DC power. This study indicates that the self-powered electrochromic system can be a candidate for monochrome displays or electronic billboards.
TL;DR: In this paper, ordered macroporous WO3 thin films prepared by the template-assisted sol-gel method were analyzed and the principle finding was that the ordered multi-layer interconnected porous structure facilitates the diffusion of ions/electrons as well as the light transmission.
TL;DR: In this article, the authors used layer-by-layer (LbL) assembly as a processing technique, and successfully assembled hybrid electrodes containing polyaniline and vanadium pentoxide (V2O5).
Abstract: Both polyaniline and vanadium pentoxide (V2O5) are promising electrode materials for electrochemical energy storage, but each has limitations. As a composite, the two components can interact synergistically to form an electrode better than either material alone. Using layer-by-layer (LbL) assembly as a processing technique, we successfully assembled hybrid electrodes containing polyaniline and V2O5. Assembly conditions were chosen to yield films that grew reliably and had a large cycle thickness. Assembly pH and concentration are critical parameters for this particular LbL system. For lower molar mass polyaniline, exponential film growth was observed; for higher molar mass polyaniline, linear growth was obtained. The electrochromic behavior of the film was characterized using UV–vis spectroscopy, and it was found that polyaniline dominated the electrochromic response. However, the electrochemical response possessed contributions from both polyaniline and V2O5. Films made from lower molar mass polyaniline ...
TL;DR: Great interest has been drawn to the electrochromic effect exhibited by inorganic materials, because of their possible applications in information displays, light shutters, and the application of an electrical voltage.
Abstract: Chromogenic materials can change their optical properties in response to external stimuli, such as light irradiation [ 1–3 ] (photochromic materials), temperature change [ 4 , 5 ] (thermochromic materials), exposure to gas [ 6 , 7 ] (gaschromic materials), and the application of an electrical voltage [ 8–14 ] (electrochromic materials). Great interest has been drawn to the electrochromic effect exhibited by inorganic materials, because of their possible applications in information displays, [ 15 , 16 ] light shutters, [ 17 , 18 ]
TL;DR: In this paper, the one-dimensional growth originating from anisotropic molybdate anions is successfully introduced to prepare a series of hybrid nanowires of Mo3O10(C6H8N)2·2H2O (anilinium trimolyb date), Mo 3O 10(C2H10N2) (ethylenediamine trimoly bdate) and Mo 3 O 10(c5H6N) 2·H2
Abstract: The diverse structures of molybdate anions significantly provide new opportunities to design various nanostructures of MoOx-based organic–inorganic hybrids with prominent catalytic, electrochemical and photo/electrochromic properties. In this paper, the one-dimensional (1D) growth originating from anisotropic molybdate anions is successfully introduced to prepare a series of hybrid nanowires of Mo3O10(C6H8N)2·2H2O (anilinium trimolybdate), Mo3O10(C2H10N2) (ethylenediamine trimolybdate) and Mo3O10(C5H6N)2·H2O (pyridium trimolybdate). Taking Mo3O10(C6H8N)2·2H2O for example, the 1D growth is proved to be associated with the chain-like structure of Mo3O102− anions by both experiments and quantum chemical calculations. Meanwhile, the synthesis parameters, e.g., reacting time, pH conditions and feeding ratio, show obvious influences on product morphologies based on different molybdate anions, further validating the growth mechanism. More importantly, the as-obtained MoOx/amine nanostructures remarkably exhibit tunable photochromic properties depending on their 1D structures and hybrid composites, which presents the potential to design well-tailored functional optical nanodevices.
TL;DR: In this paper, the authors correlate molecular structure effects, redox properties, and electrochromic performance for a series of rationally designed neutral-state green polymers composed of electron-rich 3,4-dioxythiophene (DOT) units.
Abstract: The continuing search for relevant structure–property relationships in the area of organic electronics is expected to impact both intrinsic material performance capability and the viability of their implementation in a broad range of device applications. Cathodically coloring π-conjugated polymer electrochromes represent a class of materials potentially attractive for low-cost and nonemissive flexible display devices including e-paper. Nonetheless, both the synthetic access to a full range of visible colors and the ability to produce solution-processable systems that switch rapidly and durably from a colored neutral state to a highly transmissive doped state upon electrochemical oxidation require that material structure–property relationships be carefully examined. In this report, we correlate molecular structure effects, redox properties, and electrochromic performance for a series of rationally designed neutral-state green polymers composed of electron-rich 3,4-dioxythiophene (DOT) units and the electro...
TL;DR: Conducting polymers that absorb three primary colors, red, green, and blue (RGB), were introduced with a yellow electrochromic polymer (Y), which provided a black color near the CIE black with L*, a*, and b* values of 32, -1, and 3.7, respectively.
Abstract: Conducting polymers that absorb three primary colors, red, green, and blue (RGB), were introduced with a yellow electrochromic polymer (Y) for the preparation of black electrochromic devices. Red poly(3-hexylthiophene) (P3HT) and blue poly(3,4-ethylenedioxythiophene) (PEDOT) were coated on one side of the electrode as a cathodically coloring electrochromic (EC) layer, while green poly(aniline-N-butylsulfonate) (PANBS) and yellow EC poly{[1,3-bis(9′,9′-dihexylfluoren-20-yl)azulenyl]-alt-[2″,7″-(9″,9″-dihexylfluorenyl]} (PDHFA) were coated on the opposite electrode to complete a complementary EC device. The yellow PDHFA layer effectively compensated for absorption below 450 nm and above the 600 nm region, which was lacking in the RGB electrode. The resultant RGBY ECD provided a black color near the CIE black with L*, a*, and b* values of 32, −1.1, and 3.7, respectively, covering a broad absorption in the visible range in the colored state. The state of the black EC device was maintained, even after the elec...
TL;DR: In this paper, a template-free method using ammonium acetate (CH3COONH4) as the capping agent was used to obtain 3WO3·H2O films.
TL;DR: In this paper, the synthesis, characterization and electrochromic applications of porous WO3 thin films with different nanocrystalline phases, such as hexagonal, monoclinic, and orthorhombic, are presented.
Abstract: Recent developments in the synthesis of transition metal oxides in the form of porous thin films have opened up opportunities in the construction of electrochromic devices with enhanced properties. In this paper, synthesis, characterization and electrochromic applications of porous WO3 thin films with different nanocrystalline phases, such as hexagonal, monoclinic, and orthorhombic, are presented. Asymmetric electrochromic devices have been constructed based on these porous WO3 thin films. XRD measurements of the intercalation/deintercalation of Li+ into/from the WO3 layer of the device as a function of applied coloration/bleaching voltages show systematic changes in the lattice parameters associated with structural phase transitions in Lix WO3. Micro-Raman studies show systematic crystalline phase changes in the spectra of WO3 layers during Li+ ion intercalation and deintercalation, which agree with the XRD data. These devices exhibit interesting optical modulation (up to ∼70%) due to intercalation/deintercalation of Li ions into/from the WO3 layer of the devices as a function of applied coloration/bleaching voltages. The obtained optical modulation of the electrochromic devices indicates that, they are suitable for applications in electrochromic smart windows.
TL;DR: The absorption change and colouration efficiency at the band edge (blue-cyan region) are 4.8×10(6) m(-1) and 190 cm(2)C(-1), respectively, which are the highest reported values for inorganic electrochromes, even exceeding values of some organic materials.
Abstract: Electrochromes are materials that have the ability to reversibly change from one colour state to another with the application of an electric field. Electrochromic colouration efficiency is typically large in organic materials that are not very stable chemically. Here we show that inorganic Bi(0.9)Ca(0.1)FeO(3-0.05) thin films exhibit a prominent electrochromic effect arising from an intrinsic mechanism due to the melting of oxygen-vacancy ordering and the associated redistribution of carriers. We use a combination of optical characterization techniques in conjunction with high-resolution transmission electron microscopy and first-principles theory. The absorption change and colouration efficiency at the band edge (blue-cyan region) are 4.8×10(6) m(-1) and 190 cm(2) C(-1), respectively, which are the highest reported values for inorganic electrochromes, even exceeding values of some organic materials.
TL;DR: The synthesis of two new blue to transmissive donor-acceptor electrochromic polymers are described, showing the advantage of an aqueous compatible electrochrome switchable in high ionic conductivity aQueous electrolytes and electrochemically switched between their colored state and a transmissive state in a KNO(3)/water electrolytes.
Abstract: This paper describes the synthesis of two new blue to transmissive donor–acceptor electrochromic polymers: a polymer synthesized using an alternating copolymerization route (ECP-Blue-A) and a polymer synthesized using a random copolymerization (ECP-Blue-R) by Stille polymerization. These polymers utilize side chains with four ester groups per donor moiety, allowing organic solubility in the ester form, and water solubility upon saponification to their carboxylate salt form. We demonstrate that the saponified polymer salts of ECP-Blue-A and ECP-Blue-R (WS-ECP-Blue-A and WS-ECP-Blue-R) can be processed from aqueous solutions into thin films by spray-casting. Upon the subsequent neutralization of the thin films, the resulting polymer acid films are solvent resistant and can be electrochemically switched between their colored state and a transmissive state in a KNO3/water electrolyte solution. The polymer acids, WS-ECP-Blue-A-acid and WS-ECP-Blue-R-acid, show electrochromic contrast Δ%T of 38% at 655 nm and 3...