Complementary electrochromic diaphragm and end product

Abstract

The application provides a complementary electrochromic film and a terminal product. The film comprises an anode conductive layer, an n-type inorganic electrochromic layer, an electrolyte layer, a p-type organic electrochromic layer and a cathode conductive layer which are arranged in a stack. The initial charge capacity of the n-type inorganic electrochromic layer and the p-type organic electrochromic layer is different. The electrochromic film further comprises a transparent pseudo-capacitive capacity-increasing layer. The capacity-increasing layer is arranged on the surface of the p-type organic electrochromic layer and / or the n-type inorganic electrochromic layer, and is used for compensating the difference in initial charge capacity between the p-type organic electrochromic layer and the n-type inorganic electrochromic layer. The electrochromic film and the terminal product provided by the application effectively solve the problem of initial capacity mismatch of the complementary electrochromic film, significantly improve the contrast and color balance of the film, have excellent optical performance and durability, and have wide practical application value.

Description

Technical Field

[0001] This application belongs to the field of electrochromic technology, and particularly relates to a complementary electrochromic film and its end product. Background Technology

[0002] The following text is for the purpose of understanding the technical background faced when this application was filed, and should not be construed as prior art.

[0003] Complementary electrochromic devices typically use p-type organic electrochromic materials to make the cathode electrochromic layer and n-type inorganic electrochromic materials to make the anode electrochromic layer. Under the action of an applied electric field, the device’s transmittance can be reversibly switched between a transparent state and a colored state by utilizing the color-changing behavior of the two materials at different potentials.

[0004] p-type organic electrochromic materials, such as conjugated polymers, typically absorb in the 400–600 nm visible light band and change from red to transparent in their oxidized state. n-type inorganic electrochromic materials, such as tungsten oxide and molybdenum oxide, usually absorb in the 600–700 nm band and change from blue to transparent in their reduced state. Ideally, by superimposing these two materials in their colored states, high full-spectrum absorption can be achieved, making the device appear almost "black" and thus providing high contrast.

[0005] However, the initial charge capacity of the n-type inorganic electrochromic material corresponding to this ideal situation will be much higher or lower than that of the p-type organic electrochromic material. This will lead to a severe mismatch in charge capacity between the two materials during the operation of the electrochromic device, resulting in color deviation in the dark state and failure to achieve the expected "black state." Furthermore, after long-term use, the imbalance in charge capacity between the two electrochromic materials will exacerbate the color imbalance. The initial charge capacity mentioned here refers to the charge capacity preset at the factory when the electrochromic device leaves the factory. Summary of the Invention

[0006] In view of this, embodiments of this application provide a complementary electrochromic film and end product that can present the desired black state with high contrast, while avoiding color imbalance caused by the mismatch of charge capacity between the two electrochromic layers.

[0007] In a first aspect, embodiments of this application provide a complementary electrochromic film, comprising a stacked anodic conductive layer, an n-type inorganic electrochromic layer, an electrolyte layer, a p-type organic electrochromic layer, and a cathode conductive layer. The initial charge capacities of the n-type inorganic electrochromic layer and the p-type organic electrochromic layer are different. The electrochromic film further includes a transparent pseudocapacitive layer disposed on the surface of the p-type organic electrochromic layer and / or the n-type inorganic electrochromic layer, for compensating for the difference in initial charge capacity between the p-type organic electrochromic layer and the n-type inorganic electrochromic layer.

[0008] By forming a transparent pseudocapacitive layer on the surface of a p-type organic electrochromic layer or an n-type inorganic electrochromic layer, the transparent pseudocapacitive layer can store charge through rapid and reversible redox reactions at or near the surface. This compensates for the initial charge capacity difference between the two electrochromic layers, thus the charge storage capacity of the electrochromic membrane provided in this application is far higher than that of conventional membranes. Specifically, the capacitive layer can accommodate and supply a large number of ions, working synergistically with the p-type organic electrochromic layer or the n-type inorganic electrochromic layer. At the same color change depth, the ion supply / extraction pressure on the electrolyte layer and the n-type inorganic electrochromic layer is greatly reduced, making it easier to maintain the charge balance of the entire membrane.

[0009] In some embodiments, the thickness of the compatibilizer layer is 5–20 μm. A thickness ≥ 5 μm ensures that the compatibilizer layer has a sufficiently large volume to store a large number of ions (i.e., sufficient pseudocapacitance). Within this range, the compatibilizer layer, being a p-type organic electrochromic layer, can provide an ample ion supply, thereby significantly improving color depth, response speed, and cycle life. A thickness ≤ 20 μm ensures that the path for ions to diffuse from the electrolyte interface to the compatibilizer layer / organic layer interface is sufficiently short. This avoids the layer becoming a new ion transport bottleneck due to excessive thickness, thus ensuring a fast response speed.

[0010] In some embodiments, the capacitance layer exhibits pseudocapacitive properties at 0–2V, transmittance ≥90% in the 400–700nm wavelength range, and electrochemical cycle life ≥10,000 cycles. This ensures complete compatibility with electrochromic systems, avoids harmful side reactions, guarantees absolute transparency of the film in the faded state without affecting the core visual effect, and ensures that the capacitance layer's lifespan is at least the entire service life of the film.

[0011] In some embodiments, the compatibilizing layer is selected from one of graphene layers, modified graphene layers, metal oxide layers, transition metal carbide layers, and transition metal nitride layers. These materials possess excellent conductivity and pseudocapacitive properties, enabling the construction of a porous nanostructure with a high specific surface area at the molecular / atomic level, providing ample storage space and rapid migration channels for ions.

[0012] In some embodiments, the metal oxide layer is selected from one of a tungsten-cesium oxide layer, a vanadium pentoxide layer, and a titanium dioxide layer. The above material layers can be selected according to specific applications, effectively improving the light transmittance of the film, preventing color shift, and extending cycle life.

[0013] In some embodiments, the compatibilizing layer is disposed between the p-type organic electrochromic layer and the electrolyte layer. In other embodiments, the compatibilizing layer is disposed between the n-type inorganic electrochromic layer and the electrolyte layer. With this configuration, ions exiting the electrolyte layer first contact the compatibilizing layer, which possesses abundant nanopores and excellent ionic conductivity, providing a high-speed channel for ions to reach the reaction interface.

[0014] In some embodiments, the electrochromic film further includes a first substrate layer and a second substrate layer, wherein the first substrate layer is disposed on the surface of the anode conductive layer and the second substrate layer is disposed on the surface of the cathode conductive layer. The thin films, such as the anode conductive layer, electrolyte layer, and electrochromic layer, are inherently very fragile (typically with thicknesses ranging from nanometers to micrometers) and can hardly exist or operate independently. The substrate layer provides robust mechanical support, giving the entire film sufficient rigidity and strength to allow for handling, installation, and processing. It prevents the internal functional layers from bending, wrinkling, scratching, or breaking due to external forces during preparation, transportation, and use, ensuring the integrity and reliability of the film.

[0015] In some embodiments, the edge of the electrochromic film has a plurality of first grooves and a plurality of second grooves. Each first groove exposes the cathode conductive layer to form a first electrode, and each second groove exposes the anode conductive layer to form a second electrode.

[0016] In some embodiments, each of the first grooves penetrates the first substrate layer, the anode conductive layer, the n-type inorganic electrochromic layer, the electrolyte layer, the capacitance layer, and the p-type organic electrochromic layer, exposing the cathode conductive layer to form a first electrode. The second groove penetrates the second substrate layer, the cathode conductive layer, the p-type organic electrochromic layer, the electrolyte layer, and the n-type inorganic electrochromic layer, exposing the anode conductive layer to form a second electrode.

[0017] The edge of the electrochromic film is further provided with a first busbar and a second busbar. The first busbar connects and conducts multiple first electrodes, and the second busbar connects and conducts multiple second electrodes. In this way, the groove directly exposes the conductive layer to form electrodes, ensuring low-resistance connections. The busbar acts like a "highway" at the edge, connecting the various electrode points into a unified circuit. Since the driving range of a single groove electrode is limited, the busbar allows current to be quickly distributed across the entire edge, avoiding differences in color-changing speed between the center and the edge. This is crucial for large-size smart windows or displays. Furthermore, the busbar mechanically reinforces the fragile groove area, preventing damage from spreading during cutting. Simultaneously, as a centralized power supply point, it simplifies external wiring connections; directly soldering to the busbar is much easier than connecting each tiny electrode, simplifying the process and facilitating mass production.

[0018] In some embodiments, the initial total charge capacity of the capacitance-enhancing layer and the n-type inorganic electrochromic layer or the p-type organic electrochromic layer in contact therewith is 5–10 mC / cm². 2 This facilitates charge balance and efficient color change. During the electrochromic process, the n-type inorganic electrochromic layer and the p-type organic electrochromic layer need to work synergistically. After applying voltage, the number of electrons and holes supplied from the cathode and anode must match the number of ions injected into the electrolyte. When the charge capacities of the two layers are equal or very close (i.e., 5–10 mC / cm³), the desired effect is achieved. 2 This means that their abilities to store or consume charge are matched. Under the same driving voltage, the number of ions that an n-type inorganic electrochromic layer can hold is exactly equal to the number of ions that a p-type organic electrochromic layer can release (and vice versa). Thus, there will be no situation where one of the two electrochromic layers has completely reacted (fully charged) while the other has not, ensuring that all the charge is efficiently used for the color-changing reaction without producing side reactions.

[0019] Secondly, embodiments of this application provide a terminal product including the electrochromic film described in the first aspect. The terminal product is selected from any one of rearview mirrors, curtain walls, car sunroofs, car side windows, car windshields, housings of electronic products, eyeglasses, vehicles, and display panels.

[0020] The terminal product provided in this application includes the electrochromic film described in the first aspect, and therefore possesses all the beneficial effects described in the first aspect. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the structure of the electrochromic film provided in the embodiments of this application. Figure 1 ;

[0023] Figure 2 This is a schematic diagram of the structure of the electrochromic film provided in the embodiments of this application. Figure 2 ;

[0024] Figure 3 This is a schematic diagram of the structure of the electrochromic film provided in the embodiments of this application. Figure 3 ;

[0025] Figure 4 This is a schematic diagram of the structure of the electrochromic film provided in the embodiments of this application. Figure 4 .

[0026] The attached icon numbers are as follows:

[0027] 10. Anode conductive layer; 20. n-type inorganic electrochromic layer; 30. Electrolyte layer; 40. p-type organic electrochromic layer; 400. Capacitance layer; 50. Cathode conductive layer; 60. First substrate layer; 70. Second substrate layer; 100. First groove; 101. Second groove; 102. First electrode; 103. Second electrode; 104. First busbar; 105. Second busbar; 106. First adhesive layer; 107. Second adhesive layer. Detailed Implementation

[0028] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of this application. However, those skilled in the art will understand that the embodiments of this application can also be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, circuits, and methods are omitted so as not to obscure the description of the embodiments of this application with unnecessary detail.

[0029] It should also be understood that the term "and / or" as used in the specification of embodiments of this application and the appended claims refers to any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0030] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to that other component.

[0031] It should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0032] Furthermore, in the description of the embodiments and the appended claims of this application, the terms "first," "second," "third," etc., are used only for distinguishing descriptions and should not be construed as indicating or implying relative importance.

[0033] In the description of embodiments in this application, references to "some embodiments" or "some embodiments" mean that one or more embodiments of this application include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, the phrases "in some embodiments," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiments, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized. "A plurality" refers to two or more.

[0034] Terminology Explanation:

[0035] Pseudocapacitance is a reversible electrochemical reaction that occurs on or near the surface of an electrode material. Also known as Faraday pseudocapacitance, it occurs when electroactive materials undergo underpotential deposition in a two-dimensional or quasi-two-dimensional space on the electrode surface or in the bulk phase, resulting in highly reversible chemical adsorption, desorption, oxidation, or reduction reactions, producing capacitance related to the electrode charging potential.

[0036] Pseudocapacitance is an intermediate state between traditional capacitors and batteries. Although the electrode active material undergoes a Faraday reaction due to electron transfer, its charging and discharging behavior is closer to that of a capacitor than a regular battery. Its charging and discharging behavior has the following characteristics: 1. The voltage of the capacitor changes approximately linearly with the amount of charge stored or released; 2. When the voltage of the capacitor changes linearly with time, the observed current or capacitance is close to a constant.

[0037] The transparent pseudocapacitor material involved in this application is available for purchase.

[0038] In a first aspect, embodiments of this application provide a complementary electrochromic film that, under the control of an external power source, can be in a black state when in a dark state.

[0039] like Figures 1 to 3 As shown, the electrochromic film includes an anode conductive layer 10, an n-type inorganic electrochromic layer 20, an electrolyte layer 30, a p-type organic electrochromic layer 40, and a cathode conductive layer 50, which are stacked together.

[0040] The electrochromic film also includes a transparent pseudocapacitive layer 400, which is disposed on the surface of the p-type organic electrochromic layer 40 and / or the n-type inorganic electrochromic layer 20. The initial charge capacity of the p-type organic electrochromic layer 40 is lower than that of the n-type inorganic electrochromic layer 20. The capacitive layer 400 compensates for the difference in initial charge capacity between the p-type organic electrochromic layer 40 and the n-type inorganic electrochromic layer 20, thereby ensuring that the total charge capacity of the capacitive layer 40 and the electrochromic layers in contact with it matches the charge capacity of the other electrochromic layer during operation. Here, "matching" means that the charge capacities are the same or close.

[0041] The transparent pseudocapacitive layer 400 can store charge through rapid and reversible redox reactions on or near the surface, which is why the charge storage capacity of the electrochromic membrane provided in this application is much higher than that of traditional membranes. Specifically, the capacitive layer 400 can accommodate and supply a large number of ions, working synergistically with the p-type organic electrochromic layer 40 or the n-type inorganic electrochromic layer in contact with it. At the same color change depth, the ion supply / extraction pressure on the electrolyte layer 30 and the n-type inorganic electrochromic layer 20 is greatly reduced, making it easier to maintain the charge balance of the entire membrane.

[0042] In another embodiment of this application, such as Figure 2As shown, the capacitance-enhancing layer 400 can also be disposed on the surface of the n-type inorganic electrochromic layer 20. In this case, the initial charge capacity of the n-type inorganic electrochromic layer 20 is lower than the charge capacity of the p-type organic electrochromic layer 40. It can be understood that, in this case, the total initial charge capacity of the capacitance-enhancing layer 400 and the n-type inorganic electrochromic layer 20 matches the initial charge capacity of the p-type organic electrochromic layer 40.

[0043] In yet another embodiment of this application, as Figure 3 As shown, capacitance enhancement layers 400 can also be provided on the surfaces of both the n-type inorganic electrochromic layer 20 and the p-type organic electrochromic layer 40, as long as the initial total charge capacity of the capacitance enhancement layer 400 and the electrochromic layer in contact with it matches the initial total charge capacity of the other capacitance enhancement layer 400 and the electrochromic layer in contact with it.

[0044] In some embodiments, the thickness of the capacitance layer 400 is 5–20 μm. A thickness ≥ 5 μm ensures that the capacitance layer 400 has a sufficiently large volume to store a large number of ions (i.e., sufficient pseudocapacitance). In specific embodiments, the thickness of the capacitance layer 400 can be any value within the range of 5–20 μm, such as 5 μm, 6 μm, 7 μm, 8 μm, 9 μm, 10 μm, 11 μm, 12 μm, 13 μm, 14 μm, 15 μm, 16 μm, 17 μm, 18 μm, 19 μm, or 20 μm. Within this range, the p-type organic electrochromic layer 40 can provide a sufficient ion supply, thereby significantly improving color depth, response speed, and cycle life. A thickness ≤ 20 μm ensures that the path for ions to diffuse from the electrolyte interface to the interface between the capacitance layer 400 and the electrochromic layer is sufficiently short. This avoids the layer becoming a new ion transport bottleneck due to excessive thickness, thus ensuring a fast response speed. If the thickness of the compatibilization layer 400 is too thin (<5μm), the ion storage capacity will be insufficient, and the effect will be greatly reduced, no different from directly doping nanomaterials, failing to fully realize the "compensation" advantage. Furthermore, ion diffusion in solid materials takes time. If the compatibilization layer 400 is too thick (>20μm), the time for ions to diffuse through the compatibilization layer 400 itself will increase significantly, resulting in a slower response.

[0045] In some embodiments, the capacitance layer 400 exhibits pseudocapacitive properties at 0–2V, with a transmittance ≥90% in the 400–700nm wavelength range and an electrochemical cycle life ≥10,000 cycles. The 0–2V voltage matches the operating voltage of the electrochromic film. This ensures that all charge exchange is used for reversible pseudocapacitive and electrochromic reactions without causing chemical decomposition of the electrolyte. The capacitance layer 400's transmittance greater than 90% in the 400–700nm wavelength range maintains the film's high transparency. As an internally stacked layer, if the capacitance layer 400 itself is colored or has haziness, it will severely impair the overall transmittance of the film. Electrochromic systems (especially complementary types) aim to achieve neutral coloring (such as gray and blue). The transparent capacitance layer 400 does not introduce additional intrinsic colors, thus avoiding color shift and ensuring the color purity of the film in its colored state. High transmittance generally also means low scattering. This ensures a clear field of view and prevents objects from appearing blurry. Pseudocapacitive materials (such as certain metal oxides) also undergo volume changes due to ion insertion / extraction during cycling. The electrochemical cycle life limit of ≥10,000 cycles for the capacitance layer 400 means that the capacitance layer 400 material has excellent structural reversibility and mechanical stability, and can withstand repeated volume expansion and contraction without pulverizing, cracking or separating from the upper and lower layers.

[0046] In some embodiments, the capacitance-enhancing layer 400 is selected from one of the following: a graphene layer, a modified graphene layer, a metal oxide layer, a transition metal carbide layer, and a transition metal nitride layer. These materials are all known advanced materials with excellent conductivity and pseudocapacitive properties.

[0047] In applications, graphene can serve as a highly efficient high-speed electron channel, significantly improving charge collection and transport efficiency within the electrochromic layer, ensuring uniform voltage distribution, and avoiding uneven coloring. Modifying graphene through chemical oxidation, doping (such as nitrogen doping), or the introduction of functional groups (forming graphene oxide followed by partial reduction) can further enhance its compatibility and dispersibility with polymer matrices. Introducing specific pseudocapacitive active sites between graphene sheets transforms the double-layer capacitance from a predominantly capacitance-based approach to a pseudocapacitive one, thereby significantly increasing specific capacitance, modulating its work function, and better matching it with the energy levels of p-type organic electrochromic layers.

[0048] In some embodiments, the metal oxide layer is selected from one of a tungsten-cesium oxide layer, a vanadium pentoxide layer, and a titanium dioxide layer. Metal oxide layers (especially non-stoichiometric, oxygen-deficient oxides) store charge through reversible changes in the valence state of metal ions, resulting in high specific capacity. The above material layers can be selected according to specific applications, effectively improving the light transmittance of the electrochromic film, preventing color shift, and extending cycle life.

[0049] In applications, transition metal carbide / nitride layers possess the properties of conductive clay, combining metallic conductivity with a hydrophilic surface, making them easy to process into films. Their layered structure allows for rapid ion movement in and out, while providing a high volumetric charge storage density.

[0050] In some embodiments, such as Figure 1 As shown, the compatibilizing layer 400 is disposed between the p-type organic electrochromic layer 40 and the electrolyte layer 30. With this arrangement, ions exiting the electrolyte layer 30 first contact the compatibilizing layer 400. The compatibilizing layer 400 possesses abundant nanopores and excellent ionic conductivity, providing a high-speed channel for ions to reach the reaction interface. The compatibilizing layer 400, closely attached to the electrolyte layer 30, can rapidly store and supply ions and withstand electrochemical stress. The p-type organic electrochromic layer 40 is disposed on the side of the compatibilizing layer 400 away from the electrolyte layer 30, primarily responsible for the efficient electrochromic reaction that produces color changes. This avoids the performance compromises that might result from forcibly combining two functions (ion storage and color change) into one material. The two work synergistically through a close interface, achieving high color-changing efficiency, high speed, and long lifetime.

[0051] In other embodiments, such as Figure 2 As shown, when the capacity-enhancing layer 400 is used to provide additional compensating charge capacity to the n-type inorganic electrochromic layer 20, it is disposed between the n-type inorganic electrochromic layer 20 and the electrolyte layer 30.

[0052] In some embodiments, such as Figure 1 As shown, the electrochromic film also includes a first substrate layer 60 and a second substrate layer 70. The first substrate layer 60 is disposed on the surface of the anode conductive layer 10; the second substrate layer 70 is disposed on the surface of the cathode conductive layer 50. The anode, electrolyte, and electrochromic layer are themselves very fragile (typically with thicknesses in the nanometer to micrometer range) and can hardly exist or operate independently. The substrate layer provides robust mechanical support, giving the entire film sufficient rigidity and strength to be handled, installed, and processed; and it prevents the internal functional layers from bending, wrinkling, scratching, or breaking due to external forces during preparation, transportation, and use, ensuring the integrity and reliability of the film.

[0053] In some embodiments, such as Figure 4As shown, the edge of the electrochromic film has multiple first grooves 100 and multiple second grooves 101. Each first groove 100 penetrates the first substrate layer 60, the anode conductive layer 10, the n-type inorganic electrochromic layer 20, the electrolyte layer 30, the capacity-enhancing layer 400, and the p-type organic electrochromic layer 40, exposing the cathode conductive layer 50 to form a first electrode 102. The second groove 101 penetrates the second substrate layer 70, the cathode conductive layer 50, the p-type organic electrochromic layer 40, the electrolyte layer 30, and the n-type inorganic electrochromic layer 20, exposing the anode conductive layer 10 to form a second electrode 103.

[0054] The edge of the electrochromic film is also provided with a first busbar 104 and a second busbar 105. The first busbar 104 connects and conducts multiple first electrodes 102, and the second busbar 105 connects and conducts multiple second electrodes 103. In this way, the groove directly exposes the conductive layer to form electrodes, which ensures low-resistance connection. The busbar is like building a "highway" at the edge, connecting the various electrode points into a unified circuit. The driving range of a single groove electrode is limited, and the busbar allows the current to be quickly distributed to the entire edge, avoiding the difference in color-changing speed between the center area and the edge. This is crucial for large-size smart windows or displays. In addition, the busbar reinforces the fragile groove area to prevent the spread of damage during cutting. At the same time, as a centralized power supply point, it simplifies the external wiring connection. It is much easier to directly solder to the busbar than to connect each tiny electrode, which helps to simplify the process and facilitate mass production.

[0055] In some embodiments, such as Figure 4 As shown, the first busbar 104 is covered with a first adhesive layer 106, and the second busbar 105 is covered with a second adhesive layer 107. Grooves are formed at the edge of the electrochromic membrane, allowing moisture and oxygen from the air to easily enter the membrane. The electrolyte will degrade upon contact with water, and the electrodes and electrochromic material will undergo oxidative degradation in the presence of oxygen. The two base layers and the edge adhesive layer together form a highly hermetic encapsulation system, completely isolating the internal active components from the external environment.

[0056] In some embodiments, the initial total charge capacity of the capacitance-enhancing layer 400 and the electrochromic layer (including at least one of the n-type inorganic electrochromic layer 20 and the p-type organic electrochromic layer 40) in contact therewith is 5 to 10 mC / cm. 2 The initial total charge capacity of the other electrochromic layer is 5–10 mC / cm. 2This facilitates charge balance and efficient color change. During the electrochromic process, the n-type inorganic electrochromic layer 20 and the p-type organic electrochromic layer 40 need to work synergistically. After applying voltage, the number of electrons and holes supplied from the cathode and anode must match the number of ions injected into the electrolyte. When the initial total charge capacity of the compatibilization layer 400 and the electrochromic layer in contact with it is equal to or very close to the initial charge capacity of the other electrochromic layer (i.e., 5–10 mC / cm²), the desired effect is achieved. 2 This means that their abilities to store or consume charge are matched. Thus, there won't be a situation where one electrochromic layer has fully reacted (fully charged) while another electrochromic layer hasn't fully reacted, ensuring that all charge is efficiently used for the color-changing reaction without producing side reactions.

[0057] The electrochromic film provided in this application has the following beneficial effects:

[0058] First, it has high contrast, and can approach the black state in dark states, achieving high-intensity absorption over a wider spectral range (400-700nm).

[0059] Secondly, it can suppress color deviation by achieving charge capacity balance through the capacity enhancement layer 400, thereby eliminating the color imbalance of the film caused by uneven charge distribution.

[0060] Third, it can improve durability and slow down the excessive oxidation or reduction of organic materials caused by charge capacity imbalance, thereby extending the service life of electrochromic films.

[0061] The following explains the layer structure of the electrochromic film provided in the embodiments of this application:

[0062] Both the first substrate layer 60 and the second substrate layer 70 are transparent substrates. The "transparent substrate" is an optically grade transparent material, specifically a flexible substrate material, such as polyethylene terephthalate (PET), polycarbonate (PC), polyimide (PI), cyclic olefin copolymers, or cellulose triacetate. The first substrate layer 60 and the second substrate layer 70 can also be glass substrates.

[0063] Both the anode conductive layer 10 and the cathode conductive layer 50 are transparent conductive layers. The material of the "transparent conductive layer" can be any transparent conductive material well known to those skilled in the art, such as indium-tin oxide (ITO), aluminum zinc oxide (AZO), fluorine-doped tin oxide (FTO), silver nanowires, graphene, carbon nanotubes, metal meshes, or silver nanoparticles.

[0064] In the n-type inorganic electrochromic layer 20, electrolyte layer 30, and p-type organic electrochromic layer 40, the n-type inorganic electrochromic layer 20 is a "reduction-colored" layer. Under an applied voltage, electrons gained from the cathode and cations injected from the electrolyte layer 30 simultaneously embed into the lattice of the material. This process is a reduction reaction (gaining electrons), causing a change in the oxidation state of the material, thereby altering its optical absorption properties and producing color. Upon fading, the process reverses, electrons and ions are extracted, and the material returns to a transparent state. The p-type organic electrochromic layer 40 is an oxidation-colored layer, working in conjunction with the n-type inorganic electrochromic layer to form a complementary device (electrochromic film). Its working principle is "opposite" to that of the n-type inorganic electrochromic layer. Under an applied voltage, it loses electrons (undergoing an oxidation reaction), and simultaneously, to maintain charge balance, anions in the electrolyte embed into its structure, or cations are extracted from its structure. This oxidation process causes its color change. When the color fades, the process reverses, electrons are gained, ions move in the opposite direction, and the original state is restored.

[0065] Electrolyte layer 30 serves as an ion bridge connecting the n-type inorganic electrochromic layer and the p-type organic electrochromic layer, and also acts as an electronic insulator. Its core function is to conduct ions, but it must block electrons. Under voltage-driven conditions, ions in the electrolyte move in a specific direction: during coloring, one type of ion moves towards the n-type inorganic electrochromic layer, while another type (or the same type of ion) moves towards the p-type organic electrochromic layer; during fading, they move in the opposite direction.

[0066] The first busbar 104 and the second busbar 105 can be made of conductive materials, including but not limited to conductive copper foil, conductive adhesive, and conductive resin, thereby forming a multi-electrode structure at the edge of the dimming film and accelerating the color-changing speed of the dimming film. The first busbar 104 and the second busbar 105 can be made of conductive materials well known to those skilled in the art, such as at least one of conductive silver paste, conductive copper paste, conductive carbon paste, nano-silver conductive ink, copper foil, copper wire, and conductive adhesive film.

[0067] The first adhesive layer 106 and the second adhesive layer 107 can also be waterproof tape or insulating tape. Their main function is to cover and seal the edge of the diaphragm, thereby preventing moisture, impurities and other contaminants from entering the interior of the diaphragm through the first groove 100 or the second groove 101, thus achieving sealing protection for the dimming diaphragm.

[0068] Secondly, embodiments of this application provide a terminal product including the electrochromic film described in the first aspect, wherein the terminal product is selected from any one of rearview mirrors, curtain walls, car sunroofs, car side windows, car windshields, housings of electronic products, eyeglasses, vehicles, and display panels.

[0069] The terminal product provided in this application includes the electrochromic film described in the first aspect, and therefore possesses all the beneficial effects described in the first aspect.

[0070] Example

[0071] Example 1A

[0072] Using an indium tin oxide (ITO) glass substrate as the first substrate layer and the anolyte conductive layer, a Prussian blue electrochromic inorganic layer (i.e., an n-type inorganic electrochromic layer) is deposited on the anolyte conductive layer side. The initial charge capacity of the n-type inorganic electrochromic layer is approximately 8 mC / cm³. 2 Spin-coat an ionic liquid-based electrolyte (such as a polycarbonate solvent system electrolyte, a mixture of ethylene carbonate (EC) / dimethyl carbonate (DMC) with LiPF6, 1-ethyl-3-methylimidazolium tetrafluoroborate ([EMIM]BF4), 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM]PF6), etc.) onto an n-type inorganic electrochromic layer. Dry.

[0073] An indium tin oxide (ITO) glass substrate was then used as the second substrate layer and the cathode conductive layer. A polythiophene polymer layer was deposited on the cathode side as a p-type organic electrochromic layer. After drying, a 10 μm thick reduced graphene oxide (rGO) solution was spin-coated onto its surface as a compatibilizer layer for the p-type organic electrochromic layer, forming a polythiophene polymer-reduced graphene oxide (rGO) composite film. The film was then dried.

[0074] The p-type organic electrochromic layer and the electrolyte layer are bonded together, thereby assembling a complementary electrochromic film with a symmetrical structure.

[0075] Example 1B:

[0076] This is essentially the same as Example 1A, except that the initial charge capacity of the n-type inorganic electrochromic layer is 5 mC / cm. 2 The thickness of the compatibilizer layer is 5 μm.

[0077] Example 1C:

[0078] It is basically the same as Example 1A, except that the thickness of the compatibilizing layer is 20 μm.

[0079] Example 2

[0080] It is basically the same as Example 1A, except that the compatibilizing layer is made of tungsten cesium oxide solution.

[0081] Example 3

[0082] The results are essentially the same as in Example 1A, except that the compatibilizing layer is made of transition metal carbide / nitride (Ti3C2T). x (solution).

[0083] Performance testing

[0084] Electrochromic films prepared in Example 1A were subjected to electrochromic tests in the 0–2V range. The results showed that:

[0085] Electrochemical performance testing showed that the initial charge capacity of the p-type composite electrochromic layer (i.e., the combination of a compatibilizing layer and a contacting p-type organic electrochromic layer) increased to approximately 8 mC / cm². 2 The initial charge capacity of the n-type inorganic electrochromic layer (8 mC / cm) 2 Matching. In its colored state, the visible light absorption spectrum of the membrane (covering the visible light region of 400-700nm) was measured using a UV-VIS-NIR spectrometer. The membrane appeared black, exhibiting broad absorption in the visible light region. Color measurement instruments were used to test the membrane's color; the color coordinate shift was reduced during the color-changing process, resulting in more uniform color. The contrast ratio was improved from 35% in the traditional design to over 50%. After 10,000 electrochromic cycles at 90℃, the p-type composite electrochromic layer maintained good structural integrity, with capacity decay of less than 10%.

[0086] The film prepared in Example 1B underwent electrochromic testing in the 0–2V range. The visible light absorption spectrum of the film (covering the visible light region of 400–700 nm) was measured using a UV-VIS-NIR spectrometer. The film exhibited a near-black state and broad absorption in the visible light region. The initial total charge capacity of the overlaid rGO and the contacting p-type organic electrochromic layer was essentially matched with the initial charge capacity of the n-type inorganic electrochromic layer, resulting in a broad visible light absorption spectrum for the film.

[0087] The film prepared in Example 1C underwent electrochromic testing in the 0–2V range. The visible light absorption spectrum of the film (covering the visible light region of 400–700 nm) was measured using a UV-VIS-NIR spectrometer. The film exhibited a near-black state and had a broad absorption range in the visible light region.

[0088] The film prepared in Example 2 was subjected to electrochromic testing in the 0–2V range. The visible light absorption spectrum of the film (covering the visible light region of 400–700 nm) was measured using a UV-VIS-NIR spectrometer. The film showed a near-black state and had a wide absorption range in the visible light region.

[0089] The film prepared in Example 3 was subjected to electrochromic testing in the 0–2V range. The visible light absorption spectrum of the film (covering the visible light region of 400–700 nm) was measured using a UV-VIS-NIR spectrometer. The film showed a near-black state and had a wide absorption range in the visible light region.

[0090] Therefore, the electrochromic film provided in this application effectively solves the capacitance mismatch between the two electrochromic layers of the complementary electrochromic film by introducing transparent pseudocapacitive materials into the p-type organic electrochromic layer and / or n-type inorganic electrochromic layer. This significantly improves the contrast and color balance of the electrochromic film, and it has excellent optical performance and durability, thus having broad practical application value.

[0091] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail or recorded in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0092] The above-described embodiments are only used to illustrate the technical solutions of the embodiments of this application, and are not intended to limit them. Although the embodiments of this application have been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of the embodiments of this application.

Claims

1. A complementary electrochromic film, comprising a stacked anodic conductive layer, an n-type inorganic electrochromic layer, an electrolyte layer, a p-type organic electrochromic layer, and a cathode conductive layer, characterized in that, The initial charge capacity of the n-type inorganic electrochromic layer and the p-type organic electrochromic layer are different. The electrochromic film also includes a transparent pseudocapacitive enhancement layer. The enhancement layer is disposed on the surface of the p-type organic electrochromic layer and / or the n-type inorganic electrochromic layer to compensate for the difference in initial charge capacity between the p-type organic electrochromic layer and the n-type inorganic electrochromic layer.

2. The complementary electrochromic film as described in claim 1, characterized in that, The thickness of the compatibilizing layer is 5–20 μm.

3. The complementary electrochromic film as described in claim 1, characterized in that, The capacitance layer exhibits pseudocapacitive properties at 0–2V, has a transmittance of ≥90% in the 400–700nm wavelength range, and an electrochemical cycle life of ≥10,000 cycles.

4. The complementary electrochromic film as described in claim 1, characterized in that, The compatibilizing layer is selected from one of the following: graphene layer, modified graphene layer, metal oxide layer, transition metal carbide layer, and transition metal nitride layer.

5. The complementary electrochromic film as described in claim 4, characterized in that, The metal oxide layer is selected from one of the following: tungsten cesium oxide layer, vanadium pentoxide layer, and titanium dioxide layer.

6. The complementary electrochromic film as described in claim 1, characterized in that, The compatibilizing layer is disposed between the p-type organic electrochromic layer and the electrolyte layer, or the compatibilizing layer is disposed between the n-type inorganic electrochromic layer and the electrolyte layer.

7. The complementary electrochromic film as described in claim 1, characterized in that, The electrochromic film further includes a first substrate layer and a second substrate layer, wherein the first substrate layer is disposed on the surface of the anode conductive layer and the second substrate layer is disposed on the surface of the cathode conductive layer.

8. The complementary electrochromic film as described in claim 7, characterized in that, The edge of the electrochromic film is provided with a plurality of first grooves and a plurality of second grooves. Each first groove penetrates the n-type inorganic electrochromic layer and / or the p-type organic electrochromic layer to expose the cathode conductive layer and form a first electrode. The second groove penetrates the p-type organic electrochromic layer and / or the n-type inorganic electrochromic layer to expose the anode conductive layer and form a second electrode. The edge of the electrochromic film is also provided with a first bus bar and a second bus bar. The first bus bar is connected to and conducts multiple first electrodes, and the second bus bar is connected to and conducts multiple second electrodes.

9. The complementary electrochromic film as described in claim 1, characterized in that, The initial total charge capacity of the n-type inorganic electrochromic layer or the p-type organic electrochromic layer in contact with the capacitance-enhancing layer is 5–10 mC / cm². 2 .

10. A terminal product, characterized in that, The complementary electrochromic film as described in any one of claims 1 to 9 is included, wherein the end product is selected from any one of rearview mirrors, curtain walls, car sunroofs, car side windows, car windshields, housings of electronic products, eyeglasses, vehicles, and display panels.

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