Metal micro-grid electrochromic energy storage integrated intelligent window and processing method thereof

Abstract

The invention discloses a metal micro-grid electrochromic energy storage integrated intelligent window and a processing method thereof, and the processing method comprises the steps: (1) coating glue on one side of a substrate, and processing a patterned photoresist groove; (2) filling conductive metal in the photoresist groove; (3) removing the photoresist to form a metal micro-grid; (4) depositing a transparent conductive material and an electrochromic functional material on the other substrate; and (5) covering the grid surface of the metal micro-mesh with electrolyte, inverting another substrate with the electrochromic functional material, and enabling the substrate to be attached to the electrolyte, thereby completing the assembly of the electrochromic energy storage integrated intelligent window. The metal micro-grid electrode in the intelligent window has conductive and ion storage functions, so that the overall structure can be simplified, and the problems of unsatisfactory response time, non-uniform color change and the like caused by asymmetrical sizes of the positive electrode and the negative electrode are effectively solved. Light and heat can be regulated and controlled through dynamic changes of the light transmittance, energy can be supplied to external electronic elements when the light transmittance changes, and the energy consumption requirement is further reduced.

Description

Technical Field

[0001] The present invention relates to the field of functional materials and energy storage devices, and in particular to a metal microgrid electrochromic energy storage integrated smart window and a processing method thereof. Background Art

[0002] Energy plays an important role in the development of human society. The demand for energy is increasing with the increasing living standards of human beings. At present, the most significant solution to reduce building energy consumption is to use energy-saving doors and windows. The interior of a building can use sunlight through the windows to obtain light and heat. The electrochromic smart window can dynamically adjust its transmission characteristics according to the indoor temperature and light intensity of the building, effectively reducing air conditioning and lighting consumption. The essence of a smart window is an electrochromic device. Electrochromism refers to the phenomenon that the electrical properties (electronic structure) and optical properties (transmittance, reflectivity or absorptivity) of the electrochromic functional material reversibly change through redox reactions under the stimulation of external voltage or current.

[0003] Effectively reducing the energy consumption of energy storage devices and improving their utilization efficiency has become a research hotspot in the energy field. Integrating electrochromic devices and energy storage devices on a transparent platform is an effective way to achieve diversified displays and save energy. The electrochromic / energy storage integrated smart window based on zinc anode shows advantages such as safety, reliability and low cost in aqueous gel electrolyte.

[0004] However, the zinc-based electrochromic / energy storage integrated smart windows reported so far have the zinc negative electrode as the core component for achieving color change and energy storage conversion. However, the zinc negative electrode has the phenomenon of intrinsic opacity and asymmetry in the size of the positive and negative electrodes, which leads to problems such as asymmetric spatial electric field and zinc dendrites, which have always plagued the breakthroughs of zinc-type bifunctional devices in terms of optical modulation range, response time, color change uniformity and energy storage density.

[0005] Therefore, in order to comprehensively improve the optical and electrical properties of zinc-based electrochromic / energy storage and realize the electrochromic smart window towards a high-performance platform with shorter response time, better color uniformity, higher energy storage density and longer working life, it is necessary to develop a new highly transparent and conductive zinc negative electrode structure, stable electrochromic positive electrode functional materials, and further optimize the transparent conductive layer to simplify the number of structural layers of the electrochromic device. Summary of the invention

[0006] In view of the above problems, the present invention provides a metal microgrid electrochromic energy storage integrated smart window. In the smart window structure, its metal microgrid electrode has the functions of conductivity and ion storage. During the discharge process, the metal loses electrons and oxidizes to metal cations to enter the solution to balance the charge. During the charging process, the metal cations obtain electrons and are redeposited on the metal microgrid. Its dual-functional characteristics can simplify the overall structure. Since metals are inherently opaque, the patterned metal microgrid has both light transmission performance while maintaining the intrinsic conductivity of the metal. The electrochromic smart window based on the metal microgrid can effectively solve the problems of long response time and uneven color change caused by the asymmetric size of the positive and negative electrodes in traditional devices. More uniform color changes can bring better use effects and aesthetics. Secondly, the positive and negative electrodes in the smart window participate in the redox reaction. The functional electrochromic positive electrode will bring about an intuitive change in light transmittance due to the change of its own valence during the electrochemical reaction, thereby regulating light and heat. In addition, there is a high redox potential difference between the positive and negative electrodes of the smart window. During one of the color-changing processes, no external voltage is required to drive it. It can spontaneously complete the color switching and provide power for external electronic components (such as temperature and humidity sensors, lighting systems), further reducing energy consumption requirements.

[0007] The technical solution of the present invention is as follows:

[0008] A metal microgrid electrochromic energy storage integrated smart window, characterized in that its structure from top to bottom is a substrate, a transparent conductive layer, an electrochromic functional material layer, an electrolyte, and a metal microgrid.

[0009] Furthermore, the above-mentioned metal microgrid electrode has the functions of electron conduction and ion storage, which can simplify the overall structure and effectively solve the problems of unsatisfactory response time and uneven color change caused by the asymmetric size of the positive and negative electrodes.

[0010] Furthermore, the above-mentioned metal micro-grid electrochromic energy storage integrated smart window also includes tape, tabs, and sealant.

[0011] Furthermore, the above-mentioned metal micro-grid electrochromic energy storage integrated smart window realizes dynamic regulation of visible light and near-infrared light through the color change of the functional material electrochromic layer at different potentials.

[0012] Furthermore, the above-mentioned metal micro-grid electrochromic energy storage integrated smart window has the functions of electrochromic and energy storage, and can realize spontaneous color switching behavior through the high redox potential difference between the positive and negative electrodes, and supply energy to external electronic components in the process, thereby reducing the need for external voltage and reducing energy consumption.

[0013] A method for processing a metal micro-grid electrochromic energy storage integrated smart window, characterized in that it comprises the steps of:

[0014] (1) coating a photoresist on one side of the substrate and processing a patterned photoresist groove;

[0015] (2) filling the patterned photoresist groove with a conductive metal;

[0016] (3) removing the photoresist to form a patterned metal microgrid;

[0017] (4) depositing a transparent conductive layer and an electrochromic functional material layer on another substrate;

[0018] (5) Covering the metal microgrid surface with electrolyte, inverting the other substrate with the electrochromic layer so that the electrochromic layer fits the electrolyte, and finally completing the device assembly.

[0019] Furthermore, in the above step (1), the material of the substrate is one of ultra-white glass, PET, PDMS, and K9 glass, the method for preparing the patterned photoresist groove is one of photolithography development, nanoimprinting, and dry film transfer, and the pattern is one of a periodic pattern such as a grid, a honeycomb, a triangle, or a non-periodic pattern such as a Thiessen polygon, a random ring, etc.

[0020] Furthermore, in the above step (2), the method of filling the conductive metal is one or more of physical vapor deposition such as magnetron sputtering, thermal evaporation, ion beam sputtering, or chemical vapor deposition, or electrodeposition, and the conductive metal material is one of zinc, aluminum, nickel, and magnesium.

[0021] Furthermore, in the above step (3), the method of removing the photoresist is one or more of dry etching, dry transfer or wet etching.

[0022] Furthermore, in the above step (4), the method of depositing the transparent conductive layer and the electrochromic layer is one or more of physical vapor deposition such as magnetron sputtering, electron beam evaporation, ion beam sputtering, or chemical vapor deposition, or electrodeposition; the material of the transparent conductive layer is one of transparent conductive materials such as ITO and FTO; the material of the electrochromic layer is one or more of color-changing materials such as WO3, PB, NiO, and V2O5.

[0023] Furthermore, in the above step (5), the method of covering the electrolyte is one of spin coating, drop coating, and spray coating, and the electrolyte material is a Li + 、Zn 2+ 、Al 3+ Mg 2+ One or more of the cationic solutions or gels, and the device assembly method is one of the methods selected from the group consisting of liquid injection sealing, vacuum sealing, and heat pressing sealing.

[0024] Compared with the prior art, the present invention has the following advantages:

[0025] 1. Compared with the traditional electrochromic structure, the metal microgrid electrochromic energy storage integrated smart window obtained by this method has a transparent conductive layer and an ion transport layer on one side replaced by a metal microgrid electrode, which simplifies the overall structure. At the same time, due to the high light transmittance of the transparent metal microgrid electrode, it can achieve the same size matching as the electrochromic functional material, solving the problems of uneven device space color change and slow response speed caused by asymmetric non-transparent zinc foil in the existing zinc-based electrochromic energy storage integrated device.

[0026] 2. The metal microgrid electrochromic energy storage integrated smart window obtained by this method has a reversible and stable redox reaction between the metal microgrid negative electrode and the electrochromic functional material layer, which makes it show different color changes under different potentials, and can realize dynamic regulation of visible light and near-infrared light.

[0027] 3. The metal microgrid electrochromic energy storage integrated smart window obtained by this method has a high redox potential difference between the metal microgrid electrode and the electrochromic positive electrode, so the device does not need to consume external power and can directly complete the color change behavior by itself. At the same time, it supplies energy to external electronic components in this process, further reducing energy consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to make the content of the present invention clearer, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work, among which:

[0029] Figure 1 A processing route for a metal microgrid electrochromic energy storage integrated smart window provided by the present invention.

[0030] Figure 2 A schematic structural diagram of a metal micro-grid electrochromic energy storage integrated smart window provided by the present invention.

[0031] Figure 3 The transmission spectra of the metal micro-grid electrochromic energy storage integrated smart window processed in Example 1 of the present invention under different states.

[0032] Figure 4 The metal microgrid electrochromic energy storage integrated smart window processed in Example 1 of the present invention is subjected to a scanning speed of 17 mV s -1 , Cyclic voltammetry curves with a voltage window in the range of 0.1-1.4V.

[0033] Figure 5The metal microgrid electrochromic energy storage integrated smart window processed in Example 1 of the present invention is subjected to a current density of 0.3 mA cm -2 , the voltage window is the charge and discharge curve in the range of 0.1-1.4V.

[0034] In the figure, 1 is a substrate, 2 is a metal microgrid, 3 is a conductive layer, 4 is an electrochromic functional material layer, 5 is an electrolyte, 6 is an adhesive tape, 7 is an electrode ear, and 8 is a sealant. DETAILED DESCRIPTION

[0035] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0036] Embodiment 1

[0037] The embodiment of the present invention provides a method for processing a metal micro-grid electrochromic energy storage integrated smart window. Figure 1 As shown, the following steps are included:

[0038] 1. Coat photoresist on one side of the substrate and process the patterned photoresist grooves. First, use acetone, deionized water, and anhydrous ethanol to ultrasonically clean the ultra-white glass substrate for 10 minutes and dry it for 12 hours. Then, spin-coat AZ4620 photoresist on the pre-cleaned glass substrate surface at 500r / min for 10s and 600r / min for 30s. Then place the photoresist-coated substrate on a 100°C hot plate and heat it for 180s to remove the solvent in the photoresist. After cooling, place the mask with the Thiessen polygon pattern on the surface of the substrate coated with the photoresist for ultraviolet exposure, and then develop it with a 0.5wt% NaOH solution to form a patterned groove of the Thiessen polygon on the photoresist surface.

[0039] 2. Fill the patterned photoresist grooves with conductive metal. First, the bottom metal is deposited. The bottom metal Cr and Cu are deposited on the patterned photoresist surface using an ion beam sputtering process. Then, using selective electrodeposition technology, the zinc foil and the sample after the bottom metal deposition are placed in ZnSO4·7H2O, NaSO4 and H3BO3 plating solutions at 2mA cm -2 Under a current density of , the patterned micro-grooves are filled with metallic zinc.

[0040] 3. Remove the photoresist to form a patterned metal microgrid. The electroplated sample was irradiated under a UV lamp for 200 seconds, then placed in a beaker containing a 0.5wt% NaOH solution for ultrasonic treatment for 10 minutes, then the sample surface was cleaned with deionized water and placed in an oven at 60°C for 2 hours to obtain a patterned metal zinc microgrid integrated on a glass substrate.

[0041] 4. Deposit a transparent conductive layer and an electrochromic layer on another substrate. First, a 200nm thick ITO was prepared as a transparent conductive layer on another glass substrate using magnetron sputtering technology. Then, a three-electrode deposition method was used in an electroplating solution containing Na2WO4·2H2O, HClO4 and H2O2, with ITO as the working electrode, Pt and Ag / AgCl as the counter electrode and reference electrode respectively, to prepare a WO3 electrochromic layer at a constant voltage of -0.7V for 700s. After electrodeposition, the surface was rinsed with deionized water and dried at room temperature for 8 hours.

[0042] 5. Cover the electrolyte on the surface of the base metal microgrid, invert the other base with the electrochromic layer, make the electrochromic layer fit the electrolyte, and finally complete the device assembly. First, prepare the gel electrolyte, add PVA to deionized water and stir, then add 1M ZnSO4 and continue stirring until the solution becomes a colorless and transparent gel. Subsequently, use the WO3 electrochromic layer as the positive electrode of the smart window and the metal zinc microgrid as the negative electrode of the smart window, lead the conductive electrode ears on the side, and stick a 5mm thick layer of 3M double-sided tape around it as a spacer, and inject Zn into its internal space. 2+ The gel electrolyte is then sealed with a layer of UV-curable resin to prevent electrolyte leakage.

[0043] The metal microgrid electrode of the metal microgrid electrochromic energy storage integrated smart window obtained in this embodiment has the functions of conductivity and ion storage, which can simplify the overall structure compared with traditional electrochromic devices. In the existing zinc-based electrochromic energy storage integrated device, the metal electrode is an opaque zinc foil or a hollow zinc frame. Due to the mismatch between the size of the metal negative electrode and the color-changing positive electrode, the electric field distribution in the internal space of the device is uneven, which leads to uneven distribution of cation gradients in the electrolyte. The metal cations introduce a long lateral path from the opaque zinc metal negative electrode to the electrochromic positive electrode, and some cations are preferentially embedded / deembedded, which ultimately leads to irregular color contrast in the device space and slower switching speed. The use of a transparent metal microgrid electrode can achieve the same size matching with the color-changing positive electrode material, and the uniform electric field brought about can cause uniform color change and fast development time. Secondly, the positive and negative electrodes in the smart window participate in the redox reaction, and the functional electrochromic positive electrode will bring about intuitive light transmittance changes due to changes in its own valence during the electrochemical reaction, thereby regulating light and heat. In addition, there is a high redox potential difference between the positive and negative electrodes of the smart window. During one of the color-changing processes, no external voltage is required to drive it. It can spontaneously complete the color switching and provide power for external electronic components (such as temperature and humidity sensors, lighting systems), further reducing energy consumption requirements.

[0044] The above embodiments are merely examples for clearly illustrating the present invention and are not limitations of the implementation methods. Those skilled in the art should understand that the scope of the present invention includes but is not limited to the above embodiments. Various changes made to the present invention in other forms without departing from the spirit or basic features of the present invention are all included in the protection scope of the present invention.

Claims

1. A metal micro-grid electrochromic energy storage integrated smart window, characterized in that: Its structure from top to bottom is substrate, transparent conductive layer, electrochromic layer, electrolyte, and transparent conductive metal microgrid.

2. The metal microgrid electrochromic energy storage integrated smart window according to claim 1, characterized in that: The smart window also includes adhesive tape, tabs, and sealant.

3. The metal microgrid electrochromic energy storage integrated smart window according to claim 1, characterized in that: The metal microgrid electrode has the functions of electron transmission and ion storage, can simplify the overall structure, and solve the problems of unsatisfactory response time and uneven color change caused by asymmetric sizes of positive and negative electrodes.

4. The metal microgrid electrochromic energy storage integrated smart window according to claim 1, characterized in that: The smart window achieves dynamic regulation of visible light and near-infrared light through the color change of the electrochromic layer at different potentials.

5. The metal microgrid electrochromic energy storage integrated smart window according to claim 1, characterized in that: The smart window has the dual functions of electrochromism and energy storage. It can achieve self-driven color switching through the high redox potential difference between the positive and negative electrodes, and supply energy to external electronic components, thereby reducing the need for external voltage and reducing energy consumption.

6. A method for manufacturing a metal microgrid electrochromic energy storage integrated smart window as claimed in any one of claims 1 to 5, characterized in that: Includes steps: (1) coating a photoresist on one side of the substrate and processing a patterned photoresist groove; (2) filling the patterned photoresist groove with a conductive metal; (3) removing the photoresist to form a metal microgrid; (4) depositing a transparent conductive layer and an electrochromic functional material layer on another substrate; (5) Covering the metal microgrid substrate with electrolyte, inverting another substrate with electrochromic functional material, making the electrochromic layer fit the electrolyte, and finally completing the device assembly.

7. The method for processing the metal microgrid electrochromic energy storage integrated smart window according to claim 6, characterized in that: In the step (1), the material of the substrate is one of ultra-white glass, PET, PDMS, and K9 glass; the method of processing the patterned photoresist groove is one of photolithography development, nanoimprinting, and dry film transfer; and the pattern is one of a grid, a honeycomb, a triangular periodic pattern, a Thiessen polygon, and a random circular non-periodic pattern; In the step (2), the method of filling the conductive metal is one or more of magnetron sputtering, thermal evaporation, ion beam sputtering physical vapor deposition or chemical vapor deposition, and electrodeposition, and the material of the conductive metal is one of zinc, aluminum, nickel, and magnesium.

8. The method for processing the metal microgrid electrochromic energy storage integrated smart window according to claim 6, characterized in that: In the step (3), the method of removing the photoresist is one or more of dry etching, dry transfer or wet etching.

9. The method for processing the metal microgrid electrochromic energy storage integrated smart window according to claim 6, characterized in that: In the step (4), the method for depositing the transparent conductive layer and the electrochromic functional material layer is one or more of physical vapor deposition such as magnetron sputtering, electron beam evaporation, ion beam sputtering, or chemical vapor deposition, or electrodeposition; the material of the transparent conductive layer is one of ITO and FTO transparent conductive materials; the material of the electrochromic layer is one or more of WO3, PB, NiO, and V2O5 functional color-changing materials.

10. The method for processing the metal microgrid electrochromic energy storage integrated smart window according to claim 6, characterized in that: In the step (5), the method of covering the electrolyte is one of spin coating, drop coating, and spray coating, and the material of the electrolyte is Li + 、Zn 2+ 、Al 3+ One or more of cationic solutions or gels, and the device assembly method is one of liquid injection sealing, vacuum sealing, and hot pressing sealing.

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