A complementary electrochromic device

Abstract

The application provides a complementary electrochromic device, which comprises a first conductive substrate, an electrochromic film layer, an electrolyte layer and a second conductive substrate arranged in sequence; the electrolyte layer comprises reversible deposition ions. Compared with the prior art, the application firstly introduces the reversible deposition / dissolution reaction between metal ions and metal oxides into the electrochromic device, and uses the reversible deposition / dissolution reaction as a charge release / storage medium of the device, effectively solves the problem that the electrochemical process of the traditional counter electrode material (such as nickel oxide, prussian blue, etc.) does not match the electrochromic film layer, and realizes a stable cycle of 5000 times. Further preferably, by reasonably selecting and matching the electrochromic film layer, the electrolyte layer and the protective electrode layer, the electrochromic device with the ultraviolet-visible-infrared full-spectrum modulation performance and high cycle stability can be realized.

Description

Technical Field

[0001] This invention belongs to the field of electrochromic technology, and particularly relates to a complementary electrochromic dimming device. Background Technology

[0002] Electrochromic technology can cause significant and reversible changes in the optical properties of materials, such as transmittance, absorptivity, and reflectivity, by applying an external bias voltage. Due to its excellent control over light and heat, electrochromic technology is considered to be the most promising technology for smart windows in buildings.

[0003] Traditional electrochromic devices consist of three parts: a cathode electrochromic material (working electrode) that plays a dominant role in color change and transmittance modulation; an anode electrochromic material (counter electrode) that plays a role in charge balance, ion storage, and auxiliary color change; and cations that can be reversibly inserted / extracted from the cathode and anode electrochromic materials.

[0004] Tungsten trioxide (WO3) films are considered the most valuable cathode electrochromic material for both research and commercial applications due to their colorless transparency, high transmittance modulation window, and excellent cycling stability. In traditional electrochromic devices, anodic electrochromic materials are typically nickel oxide or Prussian blue, but these materials have poor electrochemical compatibility with WO3 films. This is reflected in two aspects: 1. The charge storage capacity of anodic electrochromic films is an order of magnitude lower than that of WO3 films; 2. During cycling, anodic electrochromic films are more prone to ion trapping than WO3 films. This makes assembled devices susceptible to phenomena such as bubble formation and transmittance modulation degradation during cycling. Summary of the Invention

[0005] In view of this, the technical problem to be solved by the present invention is to provide a complementary electroluminescent dimming device that features color complementarity, full-spectrum shielding, and long-cycle stability.

[0006] This invention provides a complementary electroluminescent dimming device, comprising a first conductive substrate, an electrochromic thin film layer, an electrolyte layer and a second conductive substrate disposed sequentially.

[0007] The electrolyte layer includes reversibly deposited ions.

[0008] Preferably, the electrochromic thin film layer is selected from one or more of inorganic color-changing material layers, polymer color-changing material layers, and organic small molecule color-changing material layers;

[0009] The inorganic color-changing material layer is formed of inorganic color-changing material; the inorganic color-changing material is selected from tungsten trioxide and / or vanadium pentoxide;

[0010] The polymer color-changing material layer is formed of a polymer color-changing material; the polymer color-changing material is one or more of polythiophene, polyaniline and their derivatives;

[0011] The organic small molecule color-changing material layer is formed of organic small molecule color-changing material; the organic small molecule color-changing material is iridoid and / or its derivatives.

[0012] Preferably, the reversible deposited ions are selected from Mn 2+ and / or Pb 2+ .

[0013] Preferably, the concentration of reversibly deposited ions in the electrolyte layer is 0.1–1 mol / L.

[0014] Preferably, the electrolyte layer further includes an ionic salt that participates in the electrochemical reaction of the electrochromic film layer and produces a color change, and a solvent required to dissolve the ionic salt.

[0015] Preferably, the cation of the ionic salt includes H+. + The concentration of cations in the electrolyte layer is 0.1–5 mol / L; the solvent is water.

[0016] Preferably, the cations of the ionic salt further include alkali metal ions, alkaline earth metal ions, and Al. 3+ One or more of the following; the alkali metal ions are selected from Li + and / or Na + The alkaline earth metal ions are selected from Mg. 2+ and / or Ca 2+ The alkali metal ions, alkaline earth metal ions and Al 3+ One or more of them with H + The molar ratio is 1:9 to 9:1.

[0017] Preferably, it further includes a protective electrode layer; the protective electrode layer is disposed between the electrolyte layer and the second conductive substrate; the protective electrode layer includes one or more of titanium dioxide, carbon materials and acid-resistant metal materials.

[0018] Preferably, the first conductive substrate and the second conductive substrate are each independently selected from indium tin oxide glass or fluorine-doped tin oxide glass.

[0019] Preferably, it includes a first conductive substrate, a tungsten trioxide layer, an electrolyte layer, a titanium dioxide layer and a second conductive substrate arranged sequentially.

[0020] The electrolyte layer includes Mn 2+ and / or Pb 2+ .

[0021] This invention provides a complementary electrochromic dimming device, comprising a first conductive substrate, an electrochromic thin film layer, an electrolyte layer, and a second conductive substrate sequentially disposed thereon; the electrolyte layer includes reversibly deposited ions. Compared with the prior art, this invention introduces for the first time a reversible deposition / dissolution reaction between metal ions and metal oxides into an electrochromic device, and utilizes it as a charge release / storage medium for the device, effectively solving the problem of mismatch between the electrochemical processes of traditional counter electrode materials (such as nickel oxide, Prussian blue, etc.) and the electrochromic thin film layer, and achieving stable cycling for 5,000 cycles.

[0022] Furthermore, by rationally selecting and matching the electrochromic thin film layer, the electrolyte layer, and the protective electrode layer, the present invention can realize an electrochromic dimming device with full-spectrum modulation performance in the ultraviolet-visible-infrared range and high cycling stability.

[0023] Furthermore, the electrolyte layer solvent of the complementary electroluminescent device provided by the present invention is water, which has the characteristics of being green and safe.

[0024] Experimental results show that the complementary electroluminescent device provided by this invention, by abandoning the traditional counter electrode material and using only high-transmittance titanium dioxide as a corrosion-resistant protective layer, enables the device to have high transmittance in the visible light region in the faded state (i.e., T). bleach ~78%.

[0025] Furthermore, the deposited manganese dioxide and the colored tungsten trioxide have complementary colors, and the device in the colored state can achieve a full-spectrum shielding effect (i.e., T0). color ~0%.

[0026] When the device is in the colored state, tungsten trioxide and manganese dioxide are located in thin film form on the working electrode and counter electrode, respectively, giving the device an excellent memory effect. When the voltage is removed, the transmittance of the colored state changes by less than 1% within 20 minutes. Attached Figure Description

[0027] Figure 1 A schematic diagram of the cross-sectional structure of the complementary electroluminescent device provided by the present invention;

[0028] Figure 2 A schematic diagram illustrating the fading process mechanism of the complementary electroluminescent device provided by this invention;

[0029] Figure 3 The WO3 thin film (left) and Mn in Example 4 of this invention 2+ Comparison of transmittance modulation spectra of reversible deposition / dissolution of MnO2 (right);

[0030] Figure 4 In Embodiment 4 of the present invention, WO3 / / H + Al3+ Mn 2+ / / Transmittance spectra of TiO2 devices at different voltages;

[0031] Figure 5 In Embodiment 4 of the present invention, WO3 / / H + Al 3+ Mn 2+ / / Transient transmittance response spectrum of TiO2 device;

[0032] Figure 6 In Embodiment 4 of the present invention, WO3 / / H + Al 3+ Mn 2+ / / Memory effect diagram of TiO2 device;

[0033] Figure 7 In Embodiment 4 of the present invention, WO3 / / H + Al 3+ Mn 2+ / / Comparison of transmittance spectra of TiO2 devices before and after 5000 cycles;

[0034] Figure 8 In Embodiment 4 of the present invention, WO3 / / H + Pb 2+ / / Transmittance modulation spectrum of TiO2 device. Detailed Implementation

[0035] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0036] The present invention provides a complementary electroluminescent dimming device, comprising a first conductive substrate, an electrochromic thin film layer, an electrolyte layer and a second conductive substrate disposed sequentially; the electrolyte layer comprises reversibly deposited ions.

[0037] See Figure 1 , Figure 1 This is a cross-sectional schematic diagram of the complementary electroluminescent device provided by the present invention.

[0038] The complementary electroluminescent device provided by the present invention includes a first conductive substrate; the first conductive substrate can be any conductive substrate known to those skilled in the art, and there are no special limitations. In the present invention, conductive glass is preferred, and indium tin oxide (ITO) glass or fluorine-doped tin oxide (FTO) glass is more preferred.

[0039] An electrochromic thin film layer is disposed on the conductive glass; the thickness of the electrochromic thin film layer is preferably 50-1000 nm, more preferably 100-800 nm, even more preferably 300-800 nm, even more preferably 400-600 nm, and most preferably 500 nm; the electrochromic thin film layer is preferably one or more of an inorganic color-changing material layer, a polymeric color-changing material layer, and an organic small molecule color-changing material layer; the inorganic color-changing material layer is formed of an inorganic color-changing material; the inorganic color-changing material is preferably tungsten trioxide and / or vanadium pentoxide; the polymeric color-changing material layer is formed of a polymeric color-changing material; the polymeric color-changing material is preferably polythiophene; the organic small molecule color-changing material layer is formed of an organic small molecule color-changing material; the organic small molecule color-changing material is preferably violet.

[0040] An electrolyte layer is disposed on the electroluminescent thin film layer; the thickness of the electrolyte layer is preferably 50-500 μm, more preferably 100-500 μm, even more preferably 200-400 μm, and most preferably 300 μm; a non-conductive frame is disposed around the electrolyte layer to prevent electrolyte outflow; the electrolyte layer includes reversibly deposited ions; the reversibly deposited ions are metal ions that can undergo a reversible deposition / dissolution reaction with metal ions and metal oxides, and are preferably Mn in this invention. 2+ and / or Pb 2 + The concentration of reversibly deposited ions in the electrolyte layer is preferably 0.1–1 mol / L, more preferably 0.2–0.8 mol / L, even more preferably 0.4–0.6 mol / L, and most preferably 0.5 mol / L. In this invention, the electrolyte layer further includes an ionic salt that participates in the electrochemical reaction of the electrochromic thin film layer and produces a color change, and a solvent required to dissolve the ionic salt. The cation of the ionic salt, i.e., the guest ion, preferably includes H+. + In this invention, the cation is dehydrogenated. + External selection also includes alkali metal ions, alkaline earth metal ions and Al 3+ One or more of the following; the alkali metal ion is preferably Li + and / or Na + The preferred alkaline earth metal ion is Mg. 2+ and / or Ca 2+ The alkali metal ions, alkaline earth metal ions and Al 3+ One or more of them with H +The molar ratio is 1:9 to 9:1, more preferably 3:7 to 7:3, even more preferably 4:6 to 6:4, and most preferably 5:5 to 6:4; the concentration of the cations in the electrolyte layer is preferably 0.1 to 5 mol / L, more preferably 0.5 to 4 mol / L, even more preferably 0.5 to 2 mol / L, even more preferably 0.6 to 1.5 mol / L, even more preferably 0.8 to 1.2 mol / L, and even more preferably 1 mol / L; the anions in the electrolyte layer can be any anions well known to those skilled in the art, and there are no special restrictions. In this invention, ClO4 is preferred. - and / or SO4 2- The solvent is one well-known to those skilled in the art, capable of dissolving ionic salts and providing reactive oxygen species (i.e., containing O). 2- The solvent used is a single or mixed solvent, preferably water in this invention, which has green and safe properties.

[0041] A second conductive substrate is disposed on the electrolyte layer; the second conductive substrate can be any conductive substrate known to those skilled in the art, and there are no special restrictions. In this invention, conductive glass is preferred, and indium tin oxide glass or fluorine-doped tin oxide glass is more preferred; the second conductive substrate and the electrochromic film layer do not conduct electrons to each other, and a non-conductive frame is preferably disposed between the two, with the electrolyte layer inside the non-conductive frame.

[0042] Because the conductivity of the second conductive substrate will decrease significantly due to corrosion by the hydrogen-ion-containing electrolyte under long-term cycling, the complementary electroluminescent device provided by the present invention preferably further includes a protective electrode layer; the protective electrode layer is disposed between the electrolyte layer and the second conductive substrate; the protective electrode layer preferably includes one or more of titanium dioxide, carbon materials and acid-resistant metal materials, more preferably titanium dioxide layer; the thickness of the protective electrode layer is preferably 0.1-10 μm, more preferably 0.5-5 μm, and even more preferably 1-2 μm.

[0043] The complementary electroluminescent device provided by the present invention preferably comprises a first conductive substrate, a tungsten trioxide layer, an electrolyte layer, a titanium dioxide layer, and a second conductive substrate arranged sequentially; the electrolyte layer comprises Mn 2+ and / or Pb 2+ .

[0044] This invention introduces a reversible deposition / dissolution reaction between metal ions and metal oxides into electrochromic devices for the first time, and utilizes it as a charge release / storage medium for the device. This effectively solves the problem of electrochemical process mismatch between traditional counter electrode materials (such as nickel oxide, Prussian blue, etc.) and electrochromic thin film layers, and achieves stable cycling for 5,000 cycles. At the same time, by rationally selecting and matching the electrochromic thin film layer, electrolyte layer, and protective electrode layer, an electrochromic dimming device with full-spectrum modulation performance in the ultraviolet-visible-infrared range and high cycling stability can be realized.

[0045] The present invention also provides a method for fabricating the above-mentioned complementary electroluminescent device, comprising the following steps: S1) depositing an electrochromic thin film layer on a first conductive substrate to obtain a color-changing electrode; S2) placing the electrochromic thin film layer of the color-changing electrode face to face with a second conductive substrate, and fabricating a non-conductive frame between them, wherein the non-conductive frame has an electrolyte inlet, and then injecting electrolyte between the color-changing electrode and the second conductive substrate through the electrolyte inlet to form an electrolyte layer, and sealing the electrolyte inlet to obtain the complementary electroluminescent device.

[0046] The first conductive substrate, the electrochromic thin film layer, the electrolyte layer, and the second conductive substrate are all as described above, and will not be repeated here.

[0047] In this invention, preferably, a protective electrode layer is also formed on the second conductive substrate, the electrochromic thin film layer of the color-changing electrode is placed face to face with the protective electrode layer of the second conductive substrate, and then a non-conductive frame is formed between them.

[0048] To further illustrate the present invention, the following describes in detail a complementary electroluminescent device provided by the present invention with reference to embodiments.

[0049] All reagents used in the following examples are commercially available.

[0050] Example 1

[0051] Preparation of electrochromic WO3 thin film

[0052] a. Preparation of peroxypolytungstate (PPTA) solution

[0053] First, weigh 6g of tungsten powder into a 1L (or larger) beaker. Then, add 60mL of 30% hydrogen peroxide solution while stirring magnetically. The solution releases a large amount of heat. After cooling to room temperature, a milky white suspension is obtained. Filter the solution twice to obtain a translucent white solution. Transfer this solution to a 250mL round-bottom flask and reflux at 51℃ for 12h, then at 65℃ for 2h, and react at 85℃ for 30min to obtain a yellow transparent PPTA solution. Add 60mL of ethanol to this solution and continue reflux at 50℃ for 24h. Store the final solution in a refrigerator at 4℃ for approximately 7 days for further aging to obtain a yellow PPTA sol.

[0054] b. Preparation of WO3 thin films by electrodeposition

[0055] A conductive substrate (ITO glass) was ultrasonically cleaned in a solution of equal proportions of water, ethanol, and acetone. The cleaned substrate served as the working electrode, a platinum sheet as the counter electrode, and a silver wire as the reference electrode. Electrodeposition was performed using a three-electrode system on a CHI660D electrochemical workstation. The electrodeposition was performed using a chronoamperometry method, with a deposition voltage range of -0.55 to -0.56 V and a deposition time of 150 s. After deposition, the film was immersed in an ethanol solution for approximately 1 minute to remove residual PPTA solution from the film surface. The film was then annealed in a muffle furnace at 300°C for 30 minutes and cooled to room temperature to obtain a WO3 film with a thickness of 500 nm.

[0056] Example 2

[0057] Preparation of protective TiO2 thin film

[0058] a. Preparation of TiO2 slurry

[0059] Measure 10 mL of titanium tetraisopropoxide and dissolve it in 20 mL of glacial acetic acid, then slowly add 10 mL of deionized water. The hydrolysis products of titanium tetraisopropoxide will precipitate out as a precipitate, which will gradually dissolve upon continued stirring, and the solution will return to its transparent state. Place this solution in a 50 mL reactor and react at 200 °C for 4 hours. After cooling to room temperature, a TiO2 slurry and mother liquor will be generated in the reactor. Transfer the mother liquor to another beaker for later use, and remove the TiO2 slurry.

[0060] b. Preparation of TiO2 thin films by blade method

[0061] Add a small amount of mother liquor to the prepared TiO2 slurry to obtain a suitable viscosity for coating, and stir evenly before use. Cut an appropriately sized FTO glass substrate, place the conductive side on the test bench, cover both ends with 3M tape of approximately 1 μm thickness, and adhere it to the test bench. Take a small amount of TiO2 slurry, spread it evenly with a scraper, and peel off the tape to obtain a TiO2 film of uniform thickness. Finally, heat-treat this film at 450℃ for 30 minutes to obtain the final TiO2 film with a thickness of 1 μm.

[0062] Example 3

[0063] Preparation of electrolyte

[0064] a. Preparation of 1M HClO4 solution

[0065] Add about 200 mL of deionized water to a 500 mL beaker. While stirring, slowly add 41 mL of 70% perchloric acid to the deionized water. After cooling, transfer the solution to a 500 mL volumetric flask and add deionized water to bring the volume to 500 mL to obtain a 1 M HClO4 solution.

[0066] b. Preparation of 1M Al(ClO4)3 solution

[0067] Add 0.10 mol of aluminum perchlorate to 100 mL of deionized water to prepare a 1 M Al(ClO4)3 solution.

[0068] c. Preparation of electrolyte containing deposited ions

[0069] Mixing 1M HClO4 solution and 1M Al(ClO4)3 solution in a specific ratio yields mixed electrolytes with varying ion ratios and a fixed cation concentration of 1M. Taking 20 mL of this mixed electrolyte, 0.01 mol of manganese sulfate (or lead perchlorate) is added to obtain the desired electrolyte solution.

[0070] Example 4

[0071] Assembly of electro-dimming devices

[0072] 1) Following the steps in Example 1, an electrochromic WO3 thin film was prepared on ITO glass by electrodeposition to obtain a color-changing electrode;

[0073] A protective TiO2 film was prepared on FTO glass by a blade coating method according to the steps of Example 2 to obtain a protective electrode;

[0074] 2) Place the electrochromic film of the color-changing electrode and the protective layer of the protective electrode face to face. A frame is formed between the color-changing electrode and the protective electrode using UV-curable adhesive, and an electrolyte inlet is provided. Glass microspheres (300 μm in diameter) are placed between the color-changing electrode and the protective electrode to control the gap between the color-changing electrode and the catalytic electrode. After curing, the electrolyte described in Example 3 is injected into the frame to obtain an electrolyte layer (thickness equal to the glass bead thickness). Then, the frame is sealed with UV-curable adhesive and cured to obtain an electroluminescent device with the structure shown below. Figure 1 As shown. Depending on the ionic salt in the electrolyte used, the device can be named WO3 / / H. + Al 3+ Mn 2+ / / TiO2 and WO3 / / H + Mn 2+ / / TiO2, etc.

[0075] In Embodiment 4 of this invention, tungsten trioxide thin films and titanium dioxide thin films are used as the working electrode and the protective electrode (or counter electrode), respectively. Manganese ions (or lead ions, etc.) are added to the aqueous proton electrolyte as an electrolyte layer. The tungsten trioxide thin film mainly functions to regulate optical transmittance in the device. The titanium dioxide thin film prevents the exposed counter electrode (such as FTO glass) from being corroded by hydrogen ions in the electrolyte. The manganese ions (or lead ions) in the electrolyte balance the electrochemical process of the tungsten trioxide thin film at the working electrode by reversibly depositing / dissolving manganese dioxide (or lead dioxide) on the protective electrode, and also provide color complementation to the colored tungsten trioxide.

[0076] With WO3 / / H + Al 3+ Mn 2+ Taking TiO2 devices as an example, the working mechanism of the device is as follows: Figure 2 As shown. During the coloring process, the WO3 electrode is subjected to a negative bias (e.g., -1.7V), and the H in the electrolyte layer... + And Al 3+ Guest ions are embedded into the WO3 thin film under an applied negative pressure, while electrons are also injected into the film, causing W... 6+ Reduced (forming W) 5+ or W 4+ The thin film changes from colorless to dark blue; at this time, the Mn in the electrolyte layer... 2+ On the TiO2 protective electrode surface, MnO2 loses electrons and reacts with the solvent H2O to form yellowish-brown MnO2, which is deposited on the TiO2 electrode surface. The device's fading process is the reverse: when a positive bias voltage (e.g., +1.0V) is applied to the working electrode, electrons and guest ions are extracted from the WO3 film, causing the film to change from dark blue to colorless; the MnO2 on the counter electrode gains electrons and reacts with H2O in the electrolyte. +The reducing dissolution causes the counter electrode to change from yellowish-brown to colorless and transparent. The color change processes on the working and protective electrodes of the device can be illustrated by equations 1.1 and 1.2, respectively:

[0077]

[0078]

[0079] To verify the complementary color superposition effect of WO3 and MnO2 films, Figure 3 The figures show WO3 and 0.5 mol / L Mn, respectively. 2+ / In-situ transmittance modulation spectrum of MnO2 in proton electrolyte (1M HClO4 solution). It can be seen that the visible light modulation capability of the WO3 film is concentrated in the 450–800 nm wavelength range (with a distinct bump peak in the 350–450 nm range, where the transmittance is approximately 30%–40%, hence appearing blue), while Mn... 2+ / MnO2's ability to modulate visible light is concentrated in the 350-450nm band (while it has almost no transmittance modulation ability in the 600-800nm ​​band, i.e., ΔT<20%). The combination of the two can show a good color complementary effect.

[0080] Figure 4 For WO3 / / H + Al 3+ Mn 2+ / / TiO2 devices (H) + With Al 3+ The concentration ratio is 4:6, H + With Al 3+ The total concentration is 1M, Mn 2+The transmittance modulation spectra of WO3 (at a concentration of 0.5 M) in the 300–1500 nm wavelength range under different driving voltages were obtained. This test was performed using a CHI660D electrochemical workstation coupled with a UV-Vis-NIR spectrophotometer. After applying a specified voltage to the device for a period of time via the electrochemical workstation, the transmittance spectrum of the target wavelength range was measured using the spectrophotometer. At a driving voltage of +1.0 V, the device was in a decolorized state, exhibiting colorless transparency, and its average transmittance in the visible light range was greater than 70%. When a driving voltage of -1.2 V was applied for 60 s, the device appeared deep blue, almost completely blocking all near-infrared light, while still maintaining approximately 30% transmittance in the 400–600 nm visible light range. This is because at lower driving voltages, the device charge was insufficient, the working electrode WO3 was not fully colored, and the deposition of MnO2 on the counter electrode was insufficient. Further increasing the driving voltage to -1.5V significantly improves the device's visible light shielding effect, with a peak transmittance of approximately 5%, an average transmittance of less than 1%, and zero transmittance in the 600–1500 nm range. The device appears as an opaque black. Even at a driving voltage of -1.7V, the device's transmittance remains less than 1% across the entire spectrum.

[0081] Figure 5 For WO3 / / H + Al 3+ Mn 2+ / / TiO2 devices (H) + With Al 3+ The concentration ratio is 4:6, H + With Al 3+ The total concentration is 1M, Mn 2+ The transient transmittance response spectra of WO3 / / H at 660 nm under square wave voltages of -1.5 V (60 s) and +1.0 V (60 s) at a concentration of 0.5 M are shown. The fading response time of the device (the time required for the device to fully reach 90% transmittance modulation of its colored or faded state) can be calculated from the figure. + Al 3+ Mn 2+ The coloring time for the TiO2 device is 9.9s, and the fading time is 6.4s.

[0082] Figure 6 For WO3 / / H + Al 3+ Mn 2+ / / TiO2 devices (H) + With Al 3+ The concentration ratio is 4:6, H + With Al 3+ The total concentration is 1M, Mn 2+The device (at a concentration of 0.5M) was colored at -1.5V for 60 seconds, followed by an open circuit condition. The real-time transmittance (at 660nm) of the device was observed over 1200 seconds. The figure shows that the transmittance change was less than 1% within 20 minutes, exhibiting excellent memory effect. This is because, in the colored state, the positive and negative charges are stored in the tungsten trioxide thin film of the working electrode and the manganese dioxide thin film of the counter electrode, respectively. Under open circuit conditions, due to the presence of the electrolyte layer, the two films do not directly contact each other. Furthermore, the electrolyte layer only conducts ions and hardly conducts electrons, making spontaneous electron gain or loss between the films difficult, thus allowing the device to maintain its colored state for a relatively long time. This excellent memory effect means that the device does not require an additional voltage to maintain its colored state, which is beneficial for realizing low-energy smart windows for buildings.

[0083] Figure 7 For WO3 / / H + Al 3+ Mn 2+ / / TiO2 devices (H) + With Al 3+ The concentration ratio is 4:6, H + With Al 3+ The total concentration is 1M, Mn 2+ The transmittance modulation spectra of the device (at a concentration of 0.5 M) before and after 5000 fading cycles at square wave voltages of -1.5 V, 20 s and +1.0 V, 20 s are compared. Compared to the initial state, the device retains more than 95% of its initial state modulation capability after 5000 cycles. The slight decrease in the transmittance spectrum of the device in the fading state is due to the slight coloration caused by the insertion of a small number of guest ions into the protective electrode titanium dioxide, which is used as the cathode electrochromic material, during cycling. The almost no decay in the transmittance spectrum of the device in the fading state before and after 5000 cycles demonstrates that the working electrode and counter electrode of this structure have good electrochemical matching.

[0084] The device structure designed in this invention, in addition to using Mn 2+ In addition to the reversible electrochemical reaction with MnO2, it also has good scalability, such as using Pb with a similar reaction mechanism. 2+ The reversible electrochemical deposition / dissolution reaction of PbO2, as the counter electrode reaction of the device, is shown in reaction equation 1.3:

[0085]

[0086] Figure 8 For WO3 / / H + Pb 2+ / / TiO2 devices (H) + At a concentration of 1M, Pb 2+The transmittance modulation spectra of the colored (-2.0V, 60s) and bleached (+1.0V, 60s) states of lead dioxide at a concentration of 0.5M were analyzed. The bleached state device maintained an average transmittance of over 70% in the visible light range, while the colored state achieved full shielding at wavelengths greater than 600nm. However, a peak was still observed at 400nm, which is attributed to the weaker absorbance of lead dioxide compared to manganese dioxide, and the presence of Pb... 2+ The deposition potential compared to Mn 2+ It needs to be higher, but the device can still appear as an opaque blue-black color when in a tinted state.

Claims

1. A complementary electroluminescent dimming device, characterized in that, The first conductive substrate, the electrochromic thin film layer, the electrolyte layer and the second conductive substrate are sequentially disposed thereon. The electrolyte layer includes reversibly deposited ions; The electrolyte layer also includes ionic salts that participate in the electrochemical reaction of the electrochromic film layer and produce color changes, as well as solvents required to dissolve the ionic salts. The cations of the ionic salt include H+. + ; The cations of the ionic salt also include alkali metal ions, alkaline earth metal ions, and Al. 3+ One or more of the following; The alkali metal ions, alkaline earth metal ions and Al 3+ One or more of them with H + The molar ratio is 1:9 to 9:

1.

2. The complementary electroluminescent dimming device according to claim 1, characterized in that, The electrochromic thin film layer is selected from one or more of inorganic color-changing material layers, polymer color-changing material layers, and organic small molecule color-changing material layers; The inorganic color-changing material layer is formed of inorganic color-changing material; the inorganic color-changing material is selected from tungsten trioxide and / or vanadium pentoxide; The polymer color-changing material layer is formed of a polymer color-changing material; the polymer color-changing material is one or more of polythiophene, polyaniline and their derivatives; The organic small molecule color-changing material layer is formed of organic small molecule color-changing material; the organic small molecule color-changing material is iridoid and / or its derivatives.

3. The complementary electroluminescent dimming device according to claim 1, characterized in that, The reversibly deposited ions are selected from Mn 2 + and / or Pb 2+ .

4. The complementary electroluminescent dimming device according to claim 1, characterized in that, The concentration of reversibly deposited ions in the electrolyte layer is 0.1~1 mol / L.

5. The complementary electroluminescent dimming device according to claim 1, characterized in that, The concentration of cations in the electrolyte layer is 0.1~5 mol / L; the solvent is water.

6. The complementary electroluminescent dimming device according to claim 1, characterized in that, The alkali metal ions are selected from Li + and / or Na + The alkaline earth metal ions are selected from Mg. 2+ and / or Ca 2+ .

7. The complementary electroluminescent dimming device according to claim 1, characterized in that, It also includes a protective electrode layer; the protective electrode layer is disposed between the electrolyte layer and the second conductive substrate; the protective electrode layer includes one or more of titanium dioxide, carbon materials and acid-resistant metal materials.

8. The complementary electroluminescent dimming device according to claim 1, characterized in that, The first conductive substrate and the second conductive substrate are each independently selected from indium tin oxide glass or fluorine-doped tin oxide glass.

9. The complementary electroluminescent dimming device according to claim 1, characterized in that, It includes a first conductive substrate, a tungsten trioxide layer, an electrolyte layer, a titanium dioxide layer and a second conductive substrate arranged sequentially. The electrolyte layer includes Mn 2+ and / or Pb 2+ .

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