Color-adjustable aqueous ion storage layer ink and electrochromic device

Abstract

The invention relates to color-adjustable water-based ion storage layer ink and an electrochromic device, in particular to primary color water-based ion storage layer ink with a specific color, which is prepared by taking one, two or more of compounds with a chemical formula of AxMy [Fe (CN) 6] or Mz [Fe (CN) 6] (wherein A is Na or / and K, and M is one of Fe, Co, Ni, Mn, Zn and Cu) as functional materials. The water-based ion storage layer printing ink with a specified color is prepared by selecting one, two or more of primary color water-based ion storage layer printing ink and simply diluting or mixing according to a specific proportion, and the color superposition type electrochromic device is prepared by taking the water-based ion storage layer printing ink as an ion storage layer. The preparation method can be used for preparing electrochromic devices with requirements on color diversity.

Description

Technical Field

[0001] The present invention relates to a color-adjustable aqueous ion storage layer ink and an electrochromic device, specifically referring to an aqueous ion storage layer ink having a chemical formula A x M y [Fe(CN)6] or M z One, two or more compounds of [Fe(CN)6] (wherein A is Na and / or K, and M is one of Fe, Co, Ni, Mn, Zn, and Cu) are used as functional materials to prepare a primary color aqueous ion storage layer ink having a specific color. When used, the aqueous ion storage layer ink having a specified color is obtained by selecting one, two or more of the primary color aqueous ion storage layer inks and simply diluting or mixing and blending them in a specific proportion, as well as a color-superimposed electrochromic device prepared with the aqueous ion storage layer as the ion storage layer. Background Art

[0002] Electrochromism refers to the phenomenon in which a material's optical properties, such as color, transmittance, and reflectivity, undergo stable, reversible changes under the influence of an applied electric field. Materials exhibiting electrochromic properties are called electrochromic materials, and devices using electrochromic materials as functional materials are called electrochromic devices.

[0003] Electrochromic devices are increasingly being used in applications such as electrochromic glass, auto color-changing skylights, anti-glare rearview mirrors, electrochromic glasses, electrochromic goggles, electrochromic labels, electrochromic anti-counterfeiting markings, electrochromic crafts, electrochromic displays, small camera shielding devices, dynamic mobile phone housings, camouflage, and electrochromic decorations. At the same time, within these electrochromic applications, consumers are increasingly demanding new color diversity from various electrochromic devices. The disadvantages of currently available inorganic, polymer, and organic small molecule electrochromic materials in terms of color diversity and application costs are becoming increasingly apparent.

[0004] Prussian blue (PB) and its analogs (PBAs) have been widely used in energy storage batteries, electrochemical catalysis, hydrogen storage, biosensors, and drug delivery due to their uniquely stable structure and physicochemical properties. Currently, PBAs, particularly manganese-based Prussian blue, have become a research hotspot for cathode materials in sodium-ion and potassium-ion batteries. Prussian blue (PB) and its analogs (PBAs) possess inherent redox properties and the ability to undergo complexation and color change with alkali metal ions such as lithium, sodium, and potassium. They represent a class of excellent electrochromic materials with advantages such as low cost, simple preparation, widespread availability of raw materials, and low toxicity.

[0005] However, some PBAs, such as manganese-based Prussian blue analogs and nickel-based Prussian blue analogs, have low color contrast in electrochromic devices because their oxidized and reduced states do not change much compared to their original colors. Therefore, some researchers have studied PB and PBAs as ion storage layer materials for electrochromic devices.

[0006] In the field of electrochromic technology, PB and PBAs are relatively early electrochromic materials or ion storage layer materials studied. However, existing research generally uses electrochemical deposition, galvanic cell deposition, hydrothermal reaction deposition, and other methods to form PB and PBAs films. These methods have low film formation efficiency, hindering their large-scale production and application as electrochromic or ion storage layer materials. The Prussian blue electrochromic inks, Prussian blue aqueous dispersions, and Prussian blue ink compositions described in some patents simply combine PB and PBAs with alcohols or surfactants, resulting in film-forming and adhesion properties that are difficult to meet practical application requirements. Research on the color diversity of PB and PBAs electrochromic devices is also limited to a limited range of colors. Even fewer studies have explored using PB and PBAs as ion storage layer materials and leveraging their color diversity to achieve color diversity in electrochromic devices.

[0007] Can the color-changing color of electrochromic devices be obtained through simple mixing like coatings, paints, and color printing inks?

[0008] Researching methods to improve the film-forming properties of PB and PBAs materials and enhance the electrochemical stability of the film layer, and finding methods to expand the color diversity of PB and PBAs materials as electrochromic materials or ion storage layer materials have become urgent issues to be solved in the application of PB and PBAs materials in the field of electrochromic technology. Summary of the Invention

[0009] The purpose of the present invention is to solve and remedy the problems encountered in the practical application of the above-mentioned existing electrochromic materials and electrochromic device technologies, and to expand the application scope of Prussian blue (abbreviated as PB) and Prussian blue analogs (abbreviated as PBAs) in the field of electrochromic technology. Based on the above purpose, the present invention provides a color-adjustable aqueous ion storage layer ink and electrochromic device, specifically referring to a water-based ion storage layer ink with a chemical formula A x M y [Fe(CN)6] or M zOne, two or more of the compounds of [Fe(CN)6] (wherein A is Na and / or K, and M is one of Fe, Co, Ni, Mn, Zn, and Cu) are used as functional materials to prepare a primary color aqueous ion storage layer ink having a specific color. When in use, by selecting one, two or more of the primary color aqueous ion storage layer inks, and simply diluting or mixing and blending them in a specific proportion, an aqueous ion storage layer ink having a specified color and a color superimposed electrochromic device prepared with the aqueous ion storage layer ink as the ion storage layer are obtained. The color of the color-adjustable aqueous ion storage layer ink has the characteristics that can be obtained by blending the primary color aqueous ion storage layer ink. The structure of the color-adjustable electrochromic device consists of a transparent electrode, an electrochromic material layer, an electrolyte layer, an ion storage layer, and a second electrode. The ion storage layer is prepared using the color-adjustable aqueous ion storage layer ink of the present invention. The colors of the electrochromic material layer before and after color change are superimposed on the colors of the ion storage layer, thereby achieving adjustable color of the electrochromic device.

[0010] The object of the present invention is achieved through the following technical solutions:

[0011] A color-adjustable aqueous ion storage layer ink, specifically a color-adjustable aqueous ion storage layer ink having a chemical formula A x M y [Fe(CN)6] or M z One, two or more compounds of [Fe(CN)6] (wherein A is Na and / or K, and M is one of Fe, Co, Ni, Mn, Zn, and Cu) are used as functional materials to prepare a primary color aqueous ion storage layer ink having a specific color. When used, the aqueous ion storage layer ink having a specified color is obtained by selecting one, two or more of the primary color aqueous ion storage layer inks and simply diluting or mixing and blending them in a specific proportion.

[0012] wherein the compound has the chemical formula A x M y [Fe(CN)6] or M z Compounds of [Fe(CN)6] (wherein A is Na or K, and M is one of Fe, Co, Ni, Mn, Zn, and Cu), including ferrocyanide and ferrocyanide of Fe, Co, Ni, Mn, Zn, and Cu, with or without A, wherein x, y, and z are values ​​determined according to the valence states of M and Fe in the chemical formula; the compound particles may or may not have undergone surface chemical modification or finishing.

[0013] Since it has the chemical formula A x M y [Fe(CN)6] or M zCompounds of [Fe(CN)6] (where A is Na and / or K, and M is one of Fe, Co, Ni, Mn, Zn, and Cu) have similar electrochemical properties: these compounds can undergo electrochemical oxidation and electrochemical reduction reactions, and the electrochemical oxidation potential and electrochemical reduction potential of each compound are relatively close, so they can be mixed and used. Electrochromic devices prepared with the above compounds as ion storage layers have a chemical formula of A. x M y [Fe(CN)6] or M z The response time of the compound [Fe(CN)6] (wherein A is Na and / or K, and M is one of Fe, Co, Ni, Mn, Zn, and Cu) is relatively slow, and it can maintain its original color during the time when the color of the electrochromic material layer changes, thereby achieving the superposition of the original color of the ion storage layer and the color of the electrochromic material layer before and after the color change, or the superposition of the color of the ion storage layer after electrochemical oxidation or electrochemical reduction and the color of the electrochromic material layer before and after the color change.

[0014] The color of the color-adjustable aqueous ion storage layer ink is obtained by selecting and mixing primary color aqueous ion storage layer inks. According to the RGB color matching principle or the HSV color matching principle, the desired color aqueous ion storage layer ink can be obtained by simply mixing the appropriate primary color aqueous ion storage layer ink.

[0015] The chemical formula A x M y [Fe(CN)6] or M z Compounds of [Fe(CN)6] (wherein A is Na or K, and M is one of Fe, Co, Ni, Mn, Zn, and Cu), including ferrocyanide and ferrocyanide of Fe, Co, Ni, Mn, Zn, and Cu, with or without A. x, y, and z are values ​​determined according to the valence states of M and Fe in the chemical formula.

[0016] The color-adjustable aqueous ion storage layer ink or primary color aqueous ion storage layer ink is composed of functional materials, distilled water, a binder, a solubilizer, a coupling agent, a leveling agent, an adhesion promoter, and a pH adjuster. The binder can be one or more of cellulose ethers, water-based polyurethane prepolymers, and water-based polyacrylates; the leveling agent can be one or more of hydroxyl polyether-modified silicone oil, reactive silicone, polyoxyethylene alkylphenol ether, polyoxyethylene nonylphenyl ether, polyoxyethylene octylphenol ether, and bisphenol-A polyoxyethylene ether; the adhesion promoter can be water-based epoxy phosphate; the pH adjuster can be one or more of polystyrene sulfonic acid, dodecyl sulfonic acid, dodecylbenzene sulfonic acid, and camphor sulfonic acid; the solubilizer can be an alcohol or an ether, preferably 1,2-propylene glycol or diethylene glycol monobutyl ether; and the coupling agent can be one or more of silicon-containing coupling agents, titanium-containing coupling agents, or aluminum-containing coupling agents.

[0017] The pH value of the color-adjustable aqueous ion storage layer ink or the primary color aqueous ion storage layer ink is between 4 and 7.

[0018] The primary color aqueous ion storage layer ink used for preparing the aqueous ion storage layer ink has the same chemical composition except for the functional materials, or the primary color aqueous ion storage layer ink used for preparing the aqueous ion storage layer ink has compatible chemical compositions.

[0019] A color-adjustable electrochromic device, the structure of which consists of a transparent electrode, an electrochromic material layer, an electrolyte layer, an ion storage layer, and a second electrode. The ion storage layer is prepared using the color-adjustable aqueous ion storage layer ink described in the present invention. The color of the electrochromic device can be adjusted by superimposing the color of the electrochromic material layer before and after color change with the color of the ion storage layer, or by superimposing the color of the electrochromic material layer before and after color change with the color of the ion storage layer after electrochemical oxidation or electrochemical reduction.

[0020] The color-adjustable electrochromic device has the following structure: transparent electrode / electrochromic material layer / electrolyte layer / ion storage layer / second electrode, or transparent electrode / ion storage layer / electrolyte layer / electrochromic material layer / second electrode.

[0021] The electrochromic material layer of the color-adjustable electrochromic device can be an electrochromic material other than Prussian blue (PB) and Prussian blue analogs (PBAs), such as inorganic electrochromic materials (such as tungsten oxide, nickel oxide, vanadium pentoxide, etc.), organic-inorganic composite electrochromic materials, polymer electrochromic materials (such as polyaniline and its derivatives, polythiophene and its derivatives, polytriphenylamine and its derivatives, etc.), and organic small molecule electrochromic materials (such as viologen small molecule electrochromic materials, heteropolyacid small molecule electrochromic materials, etc.).

[0022] The color-adjustable electrochromic device can be electrochromic glass, automobile electrochromic skylight, electrochromic anti-glare rearview mirror, electrochromic glasses, electrochromic goggles, electrochromic labels, electrochromic anti-counterfeiting labels, electrochromic handicrafts, electrochromic displays, electrochromic small camera shielding devices, electrochromic mobile phone dynamic shells, electrochromic camouflage, electrochromic decorative films, electrochromic decorative panels, etc.

[0023] The steps for preparing the color-adjustable aqueous ion storage layer ink of the present invention are as follows:

[0024] Step one: selection or synthesis of functional materials.

[0025] The color of the aqueous ion storage layer ink can be prepared according to the color requirements of the desired color, starting from the ink having the chemical formula A x M y [Fe(CN)6] or M z One, two, or more compounds selected from the group consisting of [Fe(CN)6] (where A is Na and / or K, and M is one of Fe, Co, Ni, Mn, Zn, or Cu) are used as the functional material. The functional material may be a powdered material or a water-dispersed material, or may be generated by an in-situ reaction in a primary color aqueous ion storage layer ink system. The compound particles may or may not have undergone surface chemical modification or finishing.

[0026] For example, K2Mn[Fe(CN)6], K2Co[Fe(CN)6], and K2Ni[Fe(CN)6] are selected as functional materials. K2Mn[Fe(CN)6], K2Co[Fe(CN)6], and K2Ni[Fe(CN)6] can be pre-prepared powder materials, or aqueous dispersions prepared by reacting aqueous potassium ferrocyanide with aqueous MnCl2, CoCl2, and NiCl2 solutions, respectively.

[0027] Step 2: Preparation of primary color aqueous ion storage layer ink.

[0028] Functional materials, distilled water, binders, solubilizers, coupling agents, leveling agents, adhesion promoters, and pH regulators are mixed in specific proportions, and subjected to steps such as high-speed dispersion or ball milling, static defoaming, pH adjustment, secondary dispersion or ball milling, secondary static defoaming, and filtration to obtain a primary color water-based ion storage layer ink.

[0029] The connecting material may be one or more of cellulose ethers, water-based polyurethane prepolymers, and water-based polyacrylates; the leveling agent may be one or more of hydroxy polyether-modified silicone oil, active silicone, polyoxyethylene alkylphenol ether, polyoxyethylene nonylphenyl ether, polyoxyethylene octylphenol ether, and bisphenol-A polyoxyethylene ether; the adhesion promoter may be water-based epoxy phosphate; the pH adjuster may be one or more of polystyrene sulfonic acid, dodecyl sulfonic acid, dodecylbenzenesulfonic acid, and camphorsulfonic acid; the solubilizer may be an alcohol or an ether, preferably 1,2-propylene glycol or diethylene glycol monobutyl ether; and the coupling agent may be one or more of a silicon-containing coupling agent, a titanium-containing coupling agent, or an aluminum-containing coupling agent.

[0030] Step 3: Preparation of color-adjustable aqueous ion storage layer ink.

[0031] According to the RGB color matching principle or the HSV color matching principle, the selected primary color aqueous ion storage layer ink is mixed in different proportions and evenly dispersed to obtain the color-adjustable aqueous ion storage layer ink of the present invention with a specified color, thereby achieving the purpose of color adjustment.

[0032] Compared with the prior art, the color-adjustable aqueous ion storage layer ink of the present invention has the following advantages:

[0033] 1) The compound of formula A used in the present invention x M y [Fe(CN)6] or M z The compound [Fe(CN)6] (wherein A is Na and / or K, and M is one of Fe, Co, Ni, Mn, Zn, and Cu) has a wide range of raw material sources and low prices. The compound synthesis process is simple, and the synthesized compound is non-toxic or relatively less toxic, which can effectively reduce the use cost of functional materials and ensure the safety of material use.

[0034] 2) With chemical formula A x M y [Fe(CN)6] or M z The compounds of [Fe(CN)6] (wherein A is Na and / or K, and M is one of Fe, Co, Ni, Mn, Zn, and Cu) each have different colors and similar electrochemical properties. Any two of them can be mixed at will, providing feasibility for the color diversity of the color-adjustable aqueous ion storage layer ink of the present invention.

[0035] 3) The addition of a binder, solubilizer, coupling agent, leveling agent, and adhesion promoter improves the film-forming and adhesion properties of the color-adjustable aqueous ion storage layer ink of the present invention, and the prepared ion storage layer can meet the performance requirements of practical applications.

[0036] 4) The present invention adopts a method of preparing the required aqueous ion storage layer ink with a specified color by using primary color aqueous ion storage layer inks with different colors in a specific proportion. Aqueous ion storage layer inks with different colors can be prepared as needed, which can meet the requirements of some application fields of electrochromic technology for the diversity of color change.

[0037] The steps for preparing the color-adjustable electrochromic device of the present invention are as follows:

[0038] Step 1: Prepare an electrochromic material layer on a transparent electrode (such as ITO conductive glass, FTO conductive glass, nano silver wire transparent conductive film, etc.) by film-forming methods such as blade coating, slit coating, screen printing, spin coating, and spraying, and solidify it into a film.

[0039] The electrochromic material layer may be an electrochromic material other than Prussian blue (PB) and Prussian blue analogues (PBAs), such as inorganic electrochromic materials (such as tungsten oxide, nickel oxide, vanadium pentoxide, etc.), organic-inorganic composite electrochromic materials, polymer electrochromic materials (such as polyaniline and its derivatives, polythiophene and its derivatives, polytriphenylamine and its derivatives, etc.), organic small molecule electrochromic materials (such as viologen small molecule electrochromic materials, heteropolyacid small molecule electrochromic materials, etc.).

[0040] Step 2: Prepare an ion storage layer on the second electrode (such as ITO conductive glass, FTO conductive glass, nano silver wire transparent conductive film, metal foil, metal plate, flexible metal sheet) by film forming methods such as blade coating, slit coating, screen printing, spin coating, and spraying, and thermally cure the film.

[0041] The ion storage layer is prepared using the color-adjustable aqueous ion storage layer ink described in the present invention. Based on the color change requirements of the electrochromic device being prepared, the selected primary color aqueous ion storage layer inks are mixed in varying proportions and evenly dispersed according to the preparation method of the color-adjustable aqueous ion storage layer ink described in the present invention to obtain an aqueous ion storage layer ink of the specified color for use in preparing the ion storage layer.

[0042] Step 3: Coat a photocurable electrolyte or a thermally curable electrolyte on the electrochromic material layer prepared in the first step, fit the storage layer prepared in the second step to the electrochromic material layer, irradiate with ultraviolet light or heat to cure the electrolyte, and then encapsulate to obtain the desired electrochromic device.

[0043] The color-adjustable electrochromic device can be electrochromic glass, automobile electrochromic skylight, electrochromic anti-glare rearview mirror, electrochromic glasses, electrochromic goggles, electrochromic labels, electrochromic anti-counterfeiting labels, electrochromic handicrafts, electrochromic displays, electrochromic small camera shielding devices, electrochromic mobile phone dynamic shells, electrochromic camouflage, electrochromic decorative films, electrochromic decorative panels, etc.

[0044] In practice, the color-adjustable electrochromic device can be constructed with the following structure: transparent electrode / electrochromic material layer / electrolyte layer / ion storage layer / second electrode, or transparent electrode / ion storage layer / electrolyte layer / electrochromic material layer / second electrode. In other words, the ion storage layer can be formed on the transparent electrode in the first step, and the electrochromic material layer can be formed on the second electrode in the second step, and then assembled into the desired electrochromic device.

[0045] Compared with the prior art, the color-adjustable electrochromic device of the present invention has the following advantages:

[0046] 1) The color-adjustable electrochromic device of the present invention utilizes the color diversity of the color-adjustable ion storage layer and superimposes the color of the electrochromic material layer before and after color change to achieve color adjustment of the electrochromic device.

[0047] 2) Using the color-adjustable aqueous ion storage layer ink of the present invention to prepare the ion storage layer of the color-adjustable electrochromic device of the present invention can effectively reduce the response voltage range of the electrochromism and extend the cycle life of the prepared electrochromic device. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 This is the primary color water-based ion storage layer ink prepared in Example 1 and the digital picture of the effect after film formation.

[0049] Figure 2 This is a digital picture of the color-adjustable aqueous ion storage layer ink of the present invention prepared in Example 1 and the effect after film formation.

[0050] Figure 3 This is a schematic structural diagram of the color-adjustable electrochromic device of the present invention prepared in Example 2.

[0051] Figure 4 This is a digital picture of the color-changing effect of the color-adjustable electrochromic device of the present invention prepared in Example 2.

[0052] Figure 5 Schematic diagram of the structure of the electrochromic device prepared in the comparative example.

[0053] Figure 6This is a digital picture of the color-changing effect of the electrochromic device prepared in the comparative example.

[0054] Figure 7 This is an analysis diagram of the cyclic test current and voltage-time curves of the color-adjustable electrochromic device I of the present invention prepared in Example 2.

[0055] Figure 8 This is an analysis diagram of the cyclic test current and voltage-time curve of the electrochromic device prepared in the comparative example.

[0056] Figure 9 This is a current-time curve of the color-adjustable electrochromic device I of the present invention prepared in Example 2 after 500 cycles.

[0057] Figure 10 This is a current-time curve of the electrochromic device prepared in the comparative example after 150 cycles of the cycle test.

[0058] Figure 3 、 Figure 5 In the figure, 1. transparent electrode, 2. electrochromic material layer or ion storage layer, 3. electrolyte layer, 4. ion storage layer or electrochromic material layer, 5. second electrode, 6. electrode connection end, 7. electrode connection end, 8. transparent electrode, 9. electrochromic material layer, 10. electrolyte layer, 11. second electrode, 12. electrode connection end, 13. electrode connection end.

[0059] Figure 3 In the figure, when 2 is the electrochromic material layer, 4 should be the ion storage layer; when 2 is the ion storage layer, 4 should be the electrochromic material layer. DETAILED DESCRIPTION

[0060] To better understand the preparation and electrochromic effects of the color-adjustable aqueous ion storage layer ink and electrochromic device of the present invention, the present invention is further described below with reference to examples and accompanying drawings. The present invention includes, but is not limited to, the following examples.

[0061] Example 1: Preparation of the color-adjustable aqueous ion storage layer ink of the present invention.

[0062] The specific steps for preparing the color-adjustable aqueous ion storage layer ink of the present invention are as follows:

[0063] Step 1: Select KFe[Fe(CN)6], KMn[Fe(CN)6], KCo[Fe(CN)6], and KNi[Fe(CN)6] as functional materials to prepare primary color aqueous ion storage layer inks. KFe[Fe(CN)6], KMn[Fe(CN)6], KCo[Fe(CN)6], and KNi[Fe(CN)6] are aqueous dispersions prepared by reacting an aqueous solution of potassium ferrocyanide (K3Fe(CN)6) with an aqueous solution of ferrous chloride (FeCl2), an aqueous solution of manganese chloride (MnCl2), an aqueous solution of cobalt chloride (CoCl2), and an aqueous solution of nickel chloride (NiCl2), respectively.

[0064] 1) Dissolve 0.032 mol of K3Fe(CN)6 in 400 ml of distilled water to obtain a K3Fe(CN)6 aqueous solution; dissolve 0.032 mol of FeCl2 in 400 ml of distilled water to obtain a FeCl2 aqueous solution; mix the two solutions and stir them thoroughly to obtain a dark blue KFe[Fe(CN)6] aqueous dispersion.

[0065] 2) Dissolve 0.032 mol of K3Fe(CN)6 in 400 ml of distilled water to obtain a K3Fe(CN)6 aqueous solution; dissolve 0.032 mol of MnCl2 in 400 ml of distilled water to obtain a MnCl2 aqueous solution; mix the two solutions and stir them thoroughly to obtain a gray KMn[Fe(CN)6] aqueous dispersion.

[0066] 3) Dissolve 0.032 mol of K3Fe(CN)6 in 400 ml of distilled water to obtain a K3Fe(CN)6 aqueous solution; dissolve 0.032 mol of CoCl2 in 400 ml of distilled water to obtain a CoCl2 aqueous solution; mix the two solutions and stir them thoroughly to obtain a dark red KCo[Fe(CN)6] aqueous dispersion.

[0067] 4) Dissolve 0.032 mol of K3Fe(CN)6 in 400 ml of distilled water to obtain a K3Fe(CN)6 aqueous solution; dissolve 0.032 mol of NiCl2 in 400 ml of distilled water to obtain a NiCl2 aqueous solution; mix the two solutions and stir them thoroughly to obtain a yellowish-brown KNi[Fe(CN)6] aqueous dispersion.

[0068] Step 2: Prepare a primary color aqueous ion storage layer ink using the aqueous dispersion prepared in Step 1. In this example, hydroxyethyl methyl cellulose ether is used as the binder, 1,2-propylene glycol is used as the solubilizer, titanate coupling agent is used as the coupling agent, reactive silicone is used as the leveling agent, water-based epoxy phosphate is used as the adhesion promoter, and polystyrene sulfonic acid is used as the pH adjuster.

[0069] 1) 600 g of the KFe[Fe(CN)6] aqueous dispersion prepared in the first step was mixed with 35 g of hydroxyethyl methyl cellulose ether, 15 g of 1,2-propylene glycol, an appropriate amount of a titanate coupling agent, reactive silicone, and an aqueous epoxy phosphate. After high-speed dispersion, the pH value was adjusted to 6.5 using polystyrene sulfonic acid, and the mixture was allowed to stand for defoaming. The mixture was dispersed a second time, allowed to stand for a second time for defoaming, and then filtered through a 300-mesh screen bag to obtain a dark blue KFe[Fe(CN)6] primary color aqueous ion storage layer ink A.

[0070] 2) 600 g of the KMn[Fe(CN)6] aqueous dispersion prepared in the first step was mixed with 35 g of hydroxyethyl methyl cellulose ether, 15 g of 1,2-propylene glycol, an appropriate amount of titanate coupling agent, reactive silicone, and aqueous epoxy phosphate. After high-speed dispersion, the pH value was adjusted to 6.5 using polystyrene sulfonic acid, and the mixture was allowed to stand for defoaming. The mixture was dispersed a second time, allowed to stand for a second time for defoaming, and then filtered through a 300-mesh screen bag to obtain a gray KMn[Fe(CN)6] primary color aqueous ion storage layer ink B.

[0071] 3) 600 g of the KCo[Fe(CN)6] aqueous dispersion prepared in the first step was mixed with 35 g of hydroxyethyl methyl cellulose ether, 15 g of 1,2-propylene glycol, an appropriate amount of a titanate coupling agent, reactive silicone, and an aqueous epoxy phosphate. After high-speed dispersion, the pH value was adjusted to 6.5 using polystyrene sulfonic acid, and the mixture was allowed to stand for defoaming. The mixture was dispersed a second time, allowed to stand for a second time for defoaming, and then filtered through a 300-mesh screen bag to obtain a dark red KCo[Fe(CN)6] primary color aqueous ion storage layer ink C.

[0072] 4) 600 g of the KNi[Fe(CN)6] aqueous dispersion prepared in the first step was mixed with 35 g of hydroxyethyl methyl cellulose ether, 15 g of 1,2-propylene glycol, an appropriate amount of a titanate coupling agent, an active silicone, and an aqueous epoxy phosphate. After high-speed dispersion, the pH value was adjusted to 6.5 using polystyrene sulfonic acid, and the mixture was allowed to stand for defoaming. The mixture was dispersed a second time, allowed to stand for a second time for defoaming, and then filtered through a 300-mesh screen bag to obtain a khaki KNi[Fe(CN)6] primary color aqueous ion storage layer ink D.

[0073] Digital images of the appearance of the KFe[Fe(CN)6] primary color aqueous ion storage layer ink A, KMn[Fe(CN)6] primary color aqueous ion storage layer ink B, KCo[Fe(CN)6] primary color aqueous ion storage layer ink C, and KNi[Fe(CN)6] primary color aqueous ion storage layer ink D prepared in step 2, and digital images of the appearance of the film layer after coating and curing on ITO conductive glass with a square resistance of 10 ohm / sq using a 50 micron wire rod are shown as follows: Figure 1 As shown, Figure 1A, B, C, and D correspond to KFe[Fe(CN)6] primary color aqueous ion storage layer ink A (dark blue), KMn[Fe(CN)6] primary color aqueous ion storage layer ink B (gray), KCo[Fe(CN)6] primary color aqueous ion storage layer ink C (dark red), and KNi[Fe(CN)6] primary color aqueous ion storage layer ink D (khaki), respectively.

[0074] In actual application, in the preparation of primary color aqueous ion storage layer ink, each type can also use one or more of the aqueous dispersions prepared in step 1 to prepare a primary color aqueous ion storage layer ink with a specific color.

[0075] Step 3: Use the primary color aqueous ion storage layer ink prepared in the second step to formulate the color-adjustable aqueous ion storage layer ink of the present invention.

[0076] 1) 2.7 g of KFe[Fe(CN)6] primary color aqueous ion storage layer ink A was mixed with 17.7 g of KCo[Fe(CN)6] primary color aqueous ion storage layer ink C and dispersed uniformly to obtain a dark blue color-adjustable aqueous ion storage layer ink E of the present invention.

[0077] 2) 1.0 g of KFe[Fe(CN)6] primary color aqueous ion storage layer ink A was mixed with 18.0 g of KNi[Fe(CN)6] primary color aqueous ion storage layer ink D and dispersed uniformly to obtain a yellow-green color-adjustable aqueous ion storage layer ink F of the present invention.

[0078] 3) 17.2 g of KMn[Fe(CN)6] primary color aqueous ion storage layer ink B was mixed with 3.6 g of Fe[Fe(CN)6] primary color aqueous ion storage layer ink A and 1.8 g of KCo[Fe(CN)6] primary color aqueous ion storage layer ink C, and the mixture was evenly dispersed to obtain a deep blue color-adjustable aqueous ion storage layer ink G of the present invention.

[0079] 4) 18.0 g of KMn[Fe(CN)6] primary color aqueous ion storage layer ink B was mixed with 2.2 g of Fe[Fe(CN)6] primary color aqueous ion storage layer ink A and 1.0 g of KNi[Fe(CN)6] primary color aqueous ion storage layer ink D, and the mixture was uniformly dispersed to obtain a bluish-green color-adjustable aqueous ion storage layer ink H of the present invention.

[0080] Digital images of the appearance of the color-adjustable aqueous ion storage layer ink E, color-adjustable aqueous ion storage layer ink F, color-adjustable aqueous ion storage layer ink G, and color-adjustable aqueous ion storage layer ink H prepared in step 3, and digital images of the appearance of the film layer after being coated and cured on ITO conductive glass with a square resistance of 10 ohm / sq using a 50-micron wire rod. Figure 2 As shown, Figure 2 Here, E, F, G, and H correspond to the color-adjustable aqueous ion storage layer ink E (dark blue), color-adjustable aqueous ion storage layer ink F (yellow-green), color-adjustable aqueous ion storage layer ink G (dark blue), and color-adjustable aqueous ion storage layer ink H (blue-green), respectively. That is, the primary color aqueous ion storage layer inks prepared in the examples achieve the goal of achieving color-adjustable aqueous ion storage layer inks by mixing them in different proportions.

[0081] In addition to the colors prepared in the third step, the colors of the color-adjustable aqueous ion storage layer ink of the present invention can be obtained by simply mixing and blending appropriate primary color aqueous ion storage layer inks according to the RGB color matching principle or the HSV color matching principle to obtain aqueous ion storage layer inks of the desired color.

[0082] The primary color aqueous ion storage layer ink prepared in this embodiment and the color-adjustable aqueous ion storage layer ink of the present invention can be cured at a temperature between 90 and 110 degrees Celsius, and the curing temperature is low.

[0083] Example 2: Preparation of the color-adjustable electrochromic device of the present invention.

[0084] In this embodiment, the electrochromic layer of the electrochromic device is prepared using a poly(3,4-ethylenedioxythiophene)-polystyrene sulfonic acid (PEDOT:PSS) aqueous electrochromic ink with the model KV-ECM-PD6260 developed by ourselves; the electrolyte layer of the electrochromic device is prepared using a UV-curable electrolyte with the model KV-PEM-155 developed by ourselves; ITO conductive glass with a square resistance of 8-10 ohm / sq is used as the transparent electrode and the second electrode; the color-adjustable aqueous ion storage layer ink E, color-adjustable aqueous ion storage layer ink F, color-adjustable aqueous ion storage layer ink G, color-adjustable aqueous ion storage layer ink H of the present invention prepared in Example 1, and the color-adjustable aqueous ion storage layer ink within the scope of the present invention formed by diluting KCo[Fe(CN)6] primary color aqueous ion storage layer ink C with pure water in a ratio of 8:2 are used as ion storage layer materials to prepare the ion storage layers of the electrochromic device. The structure of the prepared electrochromic device is as follows Figure 3As shown, it is composed of a transparent electrode 1, an electrochromic material layer 2, an electrolyte layer 3, an ion storage layer 4, and a second electrode 5.

[0085] The specific preparation steps are as follows:

[0086] Step 1: Use the poly (3,4-ethylenedioxythiophene) - polystyrene sulfonic acid (PEDOT: PSS) water-based electrochromic ink model KV-ECM-PD6260 to coat the conductive surface of the transparent electrode 1 (i.e., ITO conductive glass with a square resistance of 8-10 ohm / sq) by wire rod coating using a 30-micron wire rod to form a film, and then heat cure at 95 degrees Celsius to obtain the electrochromic layer of the electrochromic device. Figure 3 As shown in 2.

[0087] Step 2: The color-adjustable aqueous ion storage layer ink E, color-adjustable aqueous ion storage layer ink F, color-adjustable aqueous ion storage layer ink G, color-adjustable aqueous ion storage layer ink H prepared in Example 1, and the color-adjustable aqueous ion storage layer ink within the scope of the present invention formed by diluting the primary color aqueous ion storage layer ink C of KCo[Fe(CN)6] with pure water in a ratio of 8:2 were respectively coated onto the conductive surface of the second electrode 5 (i.e., ITO conductive glass with a square resistance of 8-10 ohm / sq) using a 50-micron wire rod to form a film, and then thermally cured at 95 degrees Celsius to obtain the ion storage layer of the electrochromic device. Figure 3 As shown in 4.

[0088] The appearance of the obtained ITO conductive glass coated with the color-adjustable aqueous ion storage layer ink E, color-adjustable aqueous ion storage layer ink F, color-adjustable aqueous ion storage layer ink G, and color-adjustable aqueous ion storage layer ink H of the present invention are as follows: Figure 2 The pictures below E, F, G, and H show film layers with different colors.

[0089] Step 3: On the conductive surface prepared in the second step, the color-adjustable aqueous ion storage layer ink E, color-adjustable aqueous ion storage layer ink F, color-adjustable aqueous ion storage layer ink G, color-adjustable aqueous ion storage layer ink H, and the color-adjustable aqueous ion storage layer ink within the scope of the present invention formed by diluting KCo[Fe(CN)6] primary color aqueous ion storage layer ink C with pure water in a ratio of 8:2 and thermally cured to form a film of ITO conductive glass (i.e., transparent electrode 1) are coated with UV-curable electrolyte of model KV-PEM-155, and the conductive surface prepared in the first step is coated with poly(3,4-ethylenedioxythiophene)-polystyrene sulfonic acid (PEDOT:PSS) aqueous electrochromic ink and thermally cured to form a film of ITO conductive glass (i.e., second electrode 5), so that the electrochromic layer 2 and the ion storage layer 4 are relatively laminated, as shown in FIG. Figure 3 As shown, the color-adjustable electrochromic device of the present invention can be obtained by irradiating and curing with an ultraviolet LED lamp with a wavelength of 365 nm.

[0090] The digital images of the color-adjustable electrochromic device of the present invention before and after color change in Example 2 are prepared using the color-adjustable aqueous ion storage layer ink E, color-adjustable aqueous ion storage layer ink F, color-adjustable aqueous ion storage layer ink G, color-adjustable aqueous ion storage layer ink H of the present invention prepared in Example 1, and the color-adjustable aqueous ion storage layer ink within the scope of the present invention formed by diluting the primary color aqueous ion storage layer ink C of KCo[Fe(CN)6] with pure water in a ratio of 8:2. Figure 4 As shown in I, J, K, L, and M, Figure 4 The upper half of the figure is the color of the color-adjustable electrochromic device of the present invention before color change in Example 2. Figure 4 The lower half of the figure shows the color of the color-adjustable electrochromic device of the present invention after color change in Example 2.

[0091] The color-adjustable electrochromic devices I, J, K, L, and M prepared in Example 2 have their electrode connection terminals 6 connected to the negative electrode and their electrode connection terminals 7 connected to the positive electrode. Figure 3 As shown, by adding +2.2V DC voltage, the device will change color. Figure 4 The color shown in the lower half of the figure is faded by adding a voltage of -1.5V DC. Figure 4 The color shown in the upper half of the figure is reversible. Specifically, a color-adjustable electrochromic material is combined with the color-adjustable aqueous ion storage layer ink of the present invention to prepare a color-adjustable electrochromic device of the present invention. By adjusting the color of the ion storage layer, a variety of color changes in the electrochromic device can be achieved.

[0092] In order to further verify the beneficial effects of the color-adjustable electrochromic device prepared by the present invention, we designed a comparative example and prepared a structure as shown in FIG. Figure 5 The electrochromic device prepared in the comparative example lacks an ion storage layer compared to the color-adjustable electrochromic device of the present invention prepared in Example 2, and is composed of a transparent electrode 8, an electrochromic material layer 9, an electrolyte layer 10, and a second electrode 11. Figure 5 The thickness of the electrochromic material layer 9 of the electrochromic device prepared in the comparative example is the same as that of the electrochromic material layer of the color-adjustable electrochromic device of the present invention prepared in Example 2, and the electrolyte materials used are the same.

[0093] The electrode connection terminal 12 of the prepared comparative electrochromic device is connected to the negative electrode, and the electrode connection terminal 13 is connected to the positive electrode. Figure 5 As shown in the figure, the device will change color only when a voltage of +2.5V DC or above is applied, and will fade only when a voltage of -2.0V DC is applied. Figure 6 That is, under the same conditions, the color-adjustable electrochromic device prepared in Example 2 has a significantly lower response voltage due to the addition of the ion storage layer of the ion storage layer ink of the present invention.

[0094] The cycle test current, voltage-time curve analysis diagram of the color-adjustable electrochromic device I of the present invention prepared in Example 2, the cycle test current, voltage-time curve analysis diagram of the electrochromic device prepared in the comparative example, the cycle test current-time curve diagram of the color-adjustable electrochromic device I of the present invention prepared in Example 2 after 500 cycles, and the cycle test current-time curve diagram of the electrochromic device prepared in the comparative example after 150 cycles are shown respectively as follows: Figure 7 、 Figure 8 、 Figure 9 、 Figure 10 shown.

[0095] from Figure 7 and Figure 8 It can be seen that under the same cyclic voltage conditions (color change voltage +2.5V DC, fading voltage -2.0V DC), the fading time of the color-adjustable electrochromic device I of the present invention prepared in Example 2 is significantly shortened, as shown in FIG. Figure 7 As shown in T2 (T1 is the color change time, Figure 8(T3 is the color change time, and T4 is the fading time). However, the comparative electrochromic device without the ion storage layer ink of the present invention exhibited insufficient power supply under the same cycling voltage conditions (color change voltage +2.5 V DC, fading voltage -2.0 V DC), resulting in inconspicuous color change and fading.

[0096] The current-time curve of the color-adjustable electrochromic device I of the present invention prepared in Example 2 after 500 cycles is shown in FIG. Figure 9 As shown, after 500 cycles, the current-time curve of the electrochromic device I can still maintain a stable state, with uniform color change and stable contrast.

[0097] However, after 150 cycles, the electrochromic device prepared in the comparative example showed instability in the current-time curve of the cycle test, such as Figure 10 As shown, the device exhibits unstable color change and even fails.

[0098] The above further proves that the color-adjustable electrochromic device prepared with the color-adjustable aqueous ion storage layer ink of the present invention enables the electrochromic device to exhibit different colors while using the same electrochromic layer material, thereby achieving color adjustability. It can also effectively reduce the response voltage range of the electrochromic device, effectively improve the electrochemical cycle stability of the prepared electrochromic device, and extend the cycle service life of the prepared electrochromic device.

Claims

1. A color-adjustable aqueous ion storage layer ink, characterized by: The color-adjustable aqueous ion storage layer ink is a color-adjustable aqueous ion storage layer ink having a chemical formula A x M y [Fe(CN)6] or M z One, two or more compounds of [Fe(CN)6] (wherein A is Na and / or K, and M is one of Fe, Co, Ni, Mn, Zn, and Cu) are used as functional materials to prepare a primary color aqueous ion storage layer ink having a specific color. When used, the aqueous ion storage layer ink having a specified color is obtained by selecting one, two or more of the primary color aqueous ion storage layer inks and simply diluting or mixing and blending them in a specific proportion.

2. The color-adjustable aqueous ion storage layer ink according to claim 1, characterized in that: The color of the color-adjustable aqueous ion storage layer ink has characteristics that can be obtained by selecting a primary color aqueous ion storage layer ink for blending.

3. The color-adjustable aqueous ion storage layer ink according to claim 1, characterized in that: The chemical formula A x M y [Fe(CN)6] or M z Compounds of [Fe(CN)6] (wherein A is Na or K, and M is one of Fe, Co, Ni, Mn, Zn, and Cu), including ferrocyanide and ferrocyanide of Fe, Co, Ni, Mn, Zn, and Cu, containing or not containing A, wherein x, y, and z are values ​​determined according to the valence states of M and Fe in the chemical formula; the compound particles may or may not have undergone surface chemical modification or surface chemical modification.

4. The color-adjustable aqueous ion storage layer ink according to claim 1, characterized in that: The color-adjustable aqueous ion storage layer ink or the primary color aqueous ion storage layer ink is composed of functional materials, distilled water, a binder, a solubilizer, a coupling agent, a leveling agent, an adhesion promoter, and a pH adjuster. The binder can be one or more of cellulose ethers, water-based polyurethane prepolymers, and water-based polyacrylates. The leveling agent is one or more of hydroxyl polyether-modified silicone oil, active silicone, polyoxyethylene alkylphenol ether, polyoxyethylene nonylphenyl ether, polyoxyethylene octylphenol ether, and bisphenol-A polyoxyethylene ether. The adhesion promoter is water-based epoxy phosphate. The pH adjuster is one or more of polystyrene sulfonic acid, dodecyl sulfonic acid, dodecylbenzene sulfonic acid, and camphor sulfonic acid.

5. The color-adjustable aqueous ion storage layer ink according to claim 1, characterized in that: The pH value of the color-adjustable aqueous ion storage layer ink or the primary color aqueous ion storage layer ink is between 4 and 7.

6. The color-adjustable aqueous ion storage layer ink according to claim 1, characterized in that: The primary color aqueous ion storage layer ink used for preparing the aqueous ion storage layer ink has the same chemical composition except for the functional materials, or the primary color aqueous ion storage layer ink used for preparing the aqueous ion storage layer ink has compatible chemical compositions.

7. A color-adjustable electrochromic device, characterized in that: The structure of the color-adjustable electrochromic device consists of a transparent electrode, an electrochromic material layer, an electrolyte layer, an ion storage layer, and a second electrode, wherein the ion storage layer is prepared using the color-adjustable aqueous ion storage layer ink according to claim 1, and the color of the electrochromic material layer before and after color change is superimposed on the color of the ion storage layer, thereby achieving the adjustable color change of the electrochromic device.

8. The color-adjustable electrochromic device according to claim 7, characterized in that: The structure of the color-adjustable electrochromic device is: transparent electrode / electrochromic material layer / electrolyte layer / ion storage layer / second electrode, or transparent electrode / ion storage layer / electrolyte layer / electrochromic material layer / second electrode.

Images