A multifunctional smart window

Abstract

The present invention discloses a multifunctional smart window, which belongs to the technical field of functional materials and devices, and includes ITO glass, a first annular diaphragm, an annular copper foil, a second annular diaphragm, a graphene film and an infrared-transmitting film stacked in sequence from bottom to top; wherein the annular sizes of the first annular diaphragm, the annular copper foil and the second annular diaphragm are consistent, and the first annular diaphragm and the second annular diaphragm are infiltrated by an electrolyte solution containing zinc and lithium; the conductive surface of the ITO glass faces inward; different high and low levels are applied to the annular copper foil and the graphene film to achieve infrared regulation; different high and low levels are applied to the ITO glass and the annular copper foil to achieve transmittance regulation; at low transmittance, the ITO glass and the graphene film are used as electrodes of an external load to achieve power supply to the external load, and have an energy storage function. The present invention can take into account the three functions of transmittance change, infrared regulation and energy storage.

Description

Technical Field

[0001] The present invention belongs to the technical field of functional materials and devices, and in particular relates to a multifunctional smart window. Background Art

[0002] Electrochromism refers to the phenomenon that under the action of an external electric field, a material undergoes oxidation or reduction, resulting in a reversible change in its light transmission or reflection, which is manifested as a reversible color change in appearance. In practical applications, electrochromic materials can adjust the color change, color change speed, color change depth, etc. of the material by controlling the external electric field, so that the color change phenomenon proceeds according to a predetermined pattern. Due to the above characteristics, electrochromic devices encapsulated by electrochromic materials have been widely used in the fields of smart windows, anti-glare car rearview mirrors, etc.

[0003] At present, traditional electrochromic smart windows can only change the transmittance through an external electric field, and their functions are relatively simple, with limited heat absorption and reflection capabilities, and do not have functions such as electrical energy storage. Therefore, the development of a multifunctional color-changing device will have broad application prospects in commercial buildings, high-end residences and high-end cars.

[0004] After searching existing literature and patents, it was found that there is currently no device that can integrate infrared regulation, transmittance change and energy storage functions. Although there are a large number of papers or patents that can realize smart windows that integrate electrochromic and energy storage (Chemical Engineering Journal, 2021, 414: 128892, ACS Applied Materials & Interfaces, 2020, 12: 51978, Journal of Materials Chemistry A, 2018, 6: 11113, etc.), this three-layer device can achieve two functions of energy storage and color change (including transmittance change) in the same device, which can be used for power supply visualization or short circuit warning, etc. However, it is difficult for this device structure to take into account the function of infrared regulation on this basis (that is, it is difficult for the multifunctional smart window to control the heat dissipation performance in a colorless and transparent state). In addition, there are also three-layer devices based on materials such as polyaniline that can regulate both infrared and visible light (Journal of Materials Chemistry A, 2023, 11: 7264, Electrochimica Acta, 2022, 435: 141274, etc.), but most of these are reflective devices, and the infrared characteristics and color will change at the same time under the action of the electric field. The two functions cannot be separated and regulated, making it difficult to apply them in smart windows. It can be seen that it is necessary to break away from the structural design ideas of traditional multifunctional smart windows in order to develop a device that can integrate infrared regulation, visible light transmittance change and energy storage functions. Summary of the invention

[0005] In view of the problem that the electrochromic smart window in the prior art has a single function and is difficult to take into account multiple functions at the same time, the present invention proposes a new multi-functional smart window to take into account the three functions of transmittance change, infrared regulation and energy storage.

[0006] To achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0007] A multifunctional smart window, comprising an ITO (indium tin oxide) glass, a first annular diaphragm, an annular copper foil, a second annular diaphragm, a graphene film and an infrared-transmitting film stacked in sequence from bottom to top; wherein the annular sizes of the first annular diaphragm, the annular copper foil and the second annular diaphragm are consistent, and the first annular diaphragm and the second annular diaphragm are infiltrated with an electrolyte solution containing zinc and lithium; the conductive surface of the ITO glass faces inward;

[0008] Infrared control is achieved by applying different high and low levels to the annular copper foil and graphene film; transmittance control is achieved by applying different high and low levels to the ITO glass and the annular copper foil; when the transmittance is low, the ITO glass and graphene film are used as electrodes for the external load to power the external load, which has the function of energy storage.

[0009] Preferably, the material of the first annular diaphragm and the second annular diaphragm is one of PE (polyethylene), PP (polypropylene), glass fiber, non-woven fabric, and cellulose.

[0010] Preferably, the graphene film is prepared by CVD (chemical vapor deposition) method, and the number of layers is 20 to 200 layers.

[0011] Preferably, the material of the infrared-transmitting film is a film formed by a mixture of one or two of the following materials: Al2O3, BaF2, CaF2, KBr, Ge, MgF2, Si, ZnS, ZnSe, PMMA (polymethyl methacrylate), PE, and diamond.

[0012] Preferably, the electrolyte solution containing zinc and lithium is used as an important medium for realizing transmittance change, infrared regulation and energy storage, and is obtained by mixing component A, component B, component C, component D and component E in a molar ratio of 1:0.1:(1-4):(0.1-1):(0.0005-0.005); wherein component A is any one or more of choline chloride, choline bromide, choline iodide and choline acetate; component B is lithium chloride, lithium bromide, lithium iodide, lithium acetate, lithium perchlorate, bis(trifluoromethyl) Component C is any one or more of zinc sulfate and its hydrate, zinc perchlorate and its hydrate, zinc acetate and its hydrate, zinc nitrate and its hydrate, zinc chloride and its hydrate, zinc bis(trifluoromethylsulfonyl)imide and its hydrate, zinc trifluoromethylsulfonate and its hydrate, zinc tetrafluoroborate and its hydrate; component D is ethylene glycol, polyethylene glycol, succinonitrile, 1,3-dioxolane, sulfolane or acetamide; component E is copper sulfate, copper chloride or copper nitrate.

[0013] Preferably, during infrared regulation, the potential difference between the high level and the low level ranges from 0.5 to 1.0V; during transmittance regulation, the potential difference between the high level and the low level ranges from 0 to 2.0V.

[0014] The working principle of the multifunctional smart window proposed by the present invention is:

[0015] In the morning when light is limited, by connecting a low level to the graphene membrane and a high level to the annular copper foil, the lithium ions in the electrolyte solution are adsorbed on the surface or between the layers of the graphene membrane, making the graphene membrane in a low infrared reflectivity state, allowing more infrared heat to enter the room.

[0016] When there is sufficient sunlight at noon, by connecting a high level to the graphene film and a low level to the annular copper foil, lithium ions on the surface or between the layers of the graphene film are desorbed, making the graphene film in a state of high infrared reflectivity, allowing less infrared heat to enter the room.

[0017] When you need to rest at night, by connecting a high level to the annular copper foil and a low level to the ITO glass, the zinc ions in the zinc electrolyte solution in the first annular diaphragm are electroplated and deposited as zinc on the conductive surface of the ITO glass, thereby reducing the light transmittance of the ITO glass; thereafter, when electricity is needed at night, an external load is connected to the ITO glass and the graphene film. Since zinc and graphene have a high potential difference, the multifunctional smart window can be used as a power source to realize the power supply function;

[0018] By connecting a low level to the annular copper foil and a high level to the ITO glass, the zinc on the conductive surface of the ITO glass is ionized into zinc ions, thereby improving the light transmittance of the ITO glass.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] Different from the traditional multifunctional smart window with a three-layer structure, the multifunctional smart window provided by the present invention has a multi-layer structure to realize different functions respectively. Specifically, different high and low levels are applied to different structures to realize the separation of infrared control and transmittance control. In the case of low transmittance, it can also power the external load, thereby taking into account the three functions of transmittance change, infrared control and energy storage. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 A schematic diagram of the structure of a multifunctional smart window provided in Example 1 of the present invention;

[0022] Figure 2 A schematic diagram of the multifunctional smart window in different working modes provided by Embodiment 1 of the present invention;

[0023] Figure 3 The photos are of the ITO glass in the multifunctional smart window provided in Example 1 of the present invention in different galvanizing states; wherein (a) is before galvanizing; (b) is after galvanizing; (c) is after zinc ionization;

[0024] Figure 4 This is a scanning electron microscope image of the ITO glass after zinc plating in the multifunctional smart window provided in Example 1 of the present invention. DETAILED DESCRIPTION

[0025] The technical solution of the present invention is described in detail below in conjunction with embodiments.

[0026] Example 1

[0027] This embodiment provides a multifunctional smart window that takes into account light transmittance change, infrared regulation and energy storage, and the structure is as follows Figure 1 As shown, it includes ITO glass, a first annular diaphragm, an annular copper foil, a second annular diaphragm, a graphene film and an infrared-transmitting film stacked in sequence from bottom to top.

[0028] The first annular diaphragm, the annular copper foil and the second annular diaphragm have the same annular size, and the first annular diaphragm and the second annular diaphragm are infiltrated by an electrolyte solution containing zinc and lithium; the conductive surface of the ITO glass faces inward, serving as a substrate for reversible deposition of zinc ions in the electrolyte solution containing zinc and lithium.

[0029] In this embodiment, the materials of the first annular diaphragm and the second annular diaphragm are glass fibers, the material of the infrared-transmitting film is a PE film, and the electrolyte solution containing zinc and lithium is obtained by mixing choline chloride, lithium perchlorate, ethylene glycol, zinc chloride, and cupric chloride in a molar ratio of 1:0.1:2:0.1:0.0005.

[0030] The preparation process of the multifunctional smart window provided in this embodiment is specifically as follows:

[0031] Step 1, synthesizing a graphene film on a nickel foil by CVD, specifically: first, heating the nickel substrate to 1050 degrees Celsius for growth under the flow of 100 sccm of hydrogen and 100 sccm of argon gas; then, annealing it at 1050 degrees Celsius for 20 minutes to remove the native oxide layer; growing it for 15 minutes with 35 sccm CH4 flowing at atmospheric pressure as a carbon precursor, and then rapidly cooling the sample to room temperature under the flow of 100 sccm of hydrogen and 100 sccm of argon to obtain a nickel foil with a grown graphene film;

[0032] Step 2, after the nickel foil with the graphene film grown thereon is attached by means of a heat release tape, it is pressed onto the PE film and heated at 60 degrees Celsius to obtain the PE film with the graphene film attached thereon, wherein the number of layers of the graphene film is about 20;

[0033] Step 3, preparation of zinc-containing electrolyte solution:

[0034] Mix 10 g of choline chloride with lithium perchlorate, ethylene glycol, zinc chloride, and copper chloride in a molar ratio of 1:0.1:2:0.1:0.0005, and heat at 60 degrees Celsius overnight to ensure full and uniform dissolution;

[0035] Step 4: Assembly of the device:

[0036] Step 4.1: Cut two pieces of glass fiber diaphragm (GF / D type) into a size of 5×6 cm 2 The size of the membrane is cut, and the inside thereof is cut to obtain a rectangular ring structure with a width of 1 cm, namely, the first ring-shaped diaphragm and the second ring-shaped diaphragm; then, the first ring-shaped diaphragm and the second ring-shaped diaphragm are immersed in a zinc-containing electrolyte solution;

[0037] Step 4.2: Cut the 20 micron thick copper foil into pieces with an area of ​​5×6 cm 2 The inside of the copper foil is cut to obtain a rectangular ring structure with a width of 1 cm, i.e., a ring-shaped copper foil;

[0038] Step 4.3, 5×6cm 2 The conductive surface of the ITO glass faces upward, and the first annular diaphragm, the annular copper foil, the second annular diaphragm and the PE film with the graphene film attached are placed in sequence. The pole ears are respectively led out on the ITO glass, the annular copper foil and the graphene film, so that the corresponding ITO pole, copper pole and graphene pole are obtained; then, the device is packaged with the assistance of a vacuum plastic sealing machine to remove bubbles in the device, and finally a multifunctional smart window is obtained.

[0039] Figure 2 The schematic diagram of the multifunctional smart window in different working modes provided in this embodiment is as follows:

[0040] In the morning when light is limited, by connecting the graphene electrode to a low level and the copper electrode to a high level, the lithium ions in the electrolyte solution are adsorbed on the surface or between the layers of the graphene film, making the graphene film in a state of low infrared reflectivity, allowing more infrared heat to enter the room;

[0041] When there is sufficient sunlight at noon, by connecting the graphene electrode to a high level and the copper electrode to a low level, lithium ions on the surface or between the layers of the graphene film are desorbed, making the graphene film in a state of high infrared reflectivity, allowing less infrared heat to enter the room;

[0042] When you need to rest at night, by connecting the copper electrode to a high level and the ITO electrode to a low level, the zinc ions in the electrolyte solution in the first annular diaphragm are electroplated and deposited as zinc on the conductive surface of the ITO glass, thereby reducing the light transmittance of the ITO glass; thereafter, when you need electricity at night, you connect an external load to the ITO electrode and the graphene electrode. Since zinc and graphene have a high potential difference, the multifunctional smart window can be used as a power source to realize the power supply function;

[0043] By connecting the copper electrode to a low level and the ITO electrode to a high level, the zinc on the conductive surface of the ITO glass is ionized into zinc ions to improve the light transmittance of the ITO glass.

[0044] It can be seen from this that the infrared reflectivity regulation and the ITO glass transmittance regulation are separate and do not affect each other.

[0045] For example, before applying voltage between the annular copper foil and the ITO glass, the ITO glass is as follows Figure 3 (a) shows high transmittance; a voltage of -1.3V is applied between the annular copper foil and the ITO glass. After 30 seconds, the transmittance of the ITO glass changes significantly due to the deposition of zinc, as shown in Figure 3 (b) shows that the ITO glass after zinc deposition was observed by scanning electron microscope. Figure 4 It shows that zinc is deposited evenly on the ITO glass, which is beneficial for the obtained multifunctional smart window to reduce the light penetration into the room when working at night. Then, a voltage of 1.1V is added between the ring copper foil and the ITO glass. After 30 seconds, it can be found that the zinc is completely dissolved and the ITO glass becomes transparent again. Figure 3 (c) shows that the obtained multifunctional smart window has good reversible color change phenomenon.

[0046] The above embodiments only illustrate the principles and advantages of the present invention, and are not intended to limit the present invention. They are only intended to help understand the principles of the present invention. The protection scope of the present invention is not limited to the above configurations and embodiments. Those skilled in the art can make various other specific modifications and combinations based on the disclosed technology without departing from the essence of the present invention, but they are still within the protection scope of the present invention.

Claims

1. A multifunctional smart window, characterized in that: The invention comprises an ITO glass, a first annular diaphragm, an annular copper foil, a second annular diaphragm, a graphene film and an infrared-transmitting film stacked in sequence from bottom to top; wherein the annular sizes of the first annular diaphragm, the annular copper foil and the second annular diaphragm are consistent, and the first annular diaphragm and the second annular diaphragm are infiltrated with an electrolyte solution containing zinc and lithium; the conductive surface of the ITO glass faces inward; Infrared control is achieved by applying different high and low levels to the annular copper foil and graphene film; transmittance control is achieved by applying different high and low levels to the ITO glass and the annular copper foil; when the transmittance is low, the ITO glass and graphene film are used as electrodes for the external load to power the external load, which has the function of energy storage.

2. The multifunctional smart window according to claim 1, characterized in that: The material of the first annular diaphragm and the second annular diaphragm is one of PE, PP, glass fiber, non-woven fabric, and cellulose.

3. The multifunctional smart window according to claim 1, characterized in that: The graphene film is prepared by a CVD method, and the number of layers is 20 to 200.

4. The multifunctional smart window according to claim 1, characterized in that: The infrared-transmitting film is a film formed by mixing one or two materials selected from the group consisting of Al2O3, BaF2, CaF2, KBr, Ge, MgF2, Si, ZnS, ZnSe, PMMA, PE, and diamond.

5. The multifunctional smart window according to claim 1, characterized in that: The electrolyte solution containing zinc and lithium is obtained by mixing choline chloride, lithium perchlorate, ethylene glycol, zinc chloride and copper chloride in a molar ratio of 1:0.1:2:0.1:0.0005.

6. The multifunctional smart window according to claim 1, characterized in that: During infrared control, the potential difference between the high level and the low level ranges from 0.5 to 1.0V; during transmittance control, the potential difference between the high level and the low level ranges from 0 to 2.0V.

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