Variable-color dimming intelligent window capable of generating power through raindrops and preparation method of variable-color dimming intelligent window

Abstract

The invention discloses a color-variable dimming intelligent window capable of generating power through raindrops and a preparation method of the color-variable dimming intelligent window. The intelligent window comprises a light-transmitting substrate assembly, a temperature-sensitive dimming layer and a micro-topology friction power generation layer. The main body of the light-transmitting substrate assembly is a transparent substrate made of glass or flexible PET, and the surface of the transparent substrate is plated with a transparent conductive layer; the temperature-sensitive dimming layer is overlaid on the upper surface of the light-transmitting substrate assembly and is made of a thermochromic inorganic phase-change material, a thermochromic organic phase-change material or a thermochromic inorganic / organic phase-change material; the micro-topology friction power generation layer is composed of a thin film and a metal electrode, the thin film is made of fluoropolymer materials and overlaid on the upper surface of the temperature-sensitive dimming layer, and the metal electrode is attached to the surface of the thin film and used for converting kinetic energy generated by raindrop impact into electric energy and collecting the electric energy. By coupling photo-thermal regulation and control and raindrop energy recovery functions, the problems of failure of a dimming function and energy breakpoint of an existing intelligent window in rainy days are solved, and the intelligent window is suitable for a building energy-saving and micro-energy self-supply system.

Description

Technical Field

[0001] This invention belongs to the technical field of building energy conservation and micro-energy self-supply integrated system, and specifically relates to a color-changing light-emitting smart window that can generate electricity from raindrops and its preparation method. Background Technology

[0002] With the acceleration of urbanization, building energy consumption now accounts for more than 40% of global energy consumption, with heat loss through building windows accounting for as much as 60%. As a key component of the building envelope, glass has weak light and heat regulation capabilities, leading to a significant increase in air conditioning energy consumption and becoming one of the core challenges restricting the development of green buildings. To address this challenge, thermochromic smart window technology has emerged. This technology achieves dynamic regulation of solar radiation through the phase change properties of materials and has become one of the research hotspots in the field of building energy conservation in the past decade.

[0003] Thermochromic smart window technology primarily relies on the phase change properties of materials, adjusting their optical properties through temperature variations to regulate solar radiation. This technology effectively blocks most near-infrared light and solar radiation during hot summer months, significantly reducing indoor air conditioning load. During cold winter months, it increases indoor lighting and passive heating by improving window transmittance, thereby enhancing building energy efficiency and comfort.

[0004] However, current technologies typically only adjust light transmittance based on temperature response on sunny days or when temperatures are high. In special weather conditions such as rain, the window's intelligent dimming function fails to operate, resulting in a lack of continuous energy-saving regulation under varying climate conditions. Furthermore, when raindrops hit the window, their kinetic energy is converted into mechanical energy, but current technologies have not effectively recovered this energy, leading to a significant waste of potential renewable energy and failing to provide effective energy support for the window or building.

[0005] Therefore, the current thermochromic smart window technology has not been able to fully realize its energy-saving performance in various climate scenarios. In particular, in special environments such as rainy days, the function of smart windows still has a lot of room for improvement and urgently needs further technological innovation and improvement. Summary of the Invention

[0006] To overcome the energy waste problem in existing technologies, this invention provides a color-changing smart window that can generate electricity from raindrops and its preparation method. By coupling environmentally responsive optical control with liquid-solid interface energy harvesting function, it can achieve intelligent dimming in multiple climate scenarios and effectively recover kinetic energy by generating electricity from raindrops on rainy days.

[0007] To solve the above-mentioned technical problems and achieve the above-mentioned technical effects, the present invention is implemented through the following technical solution: A color-changing smart window capable of generating electricity from raindrops includes a light-transmitting substrate assembly, a temperature-sensitive dimming layer, and a micro-topological triboelectric layer. The main body of the light-transmitting substrate assembly is a transparent substrate made of glass or flexible PET, and the surface of the transparent substrate is coated with a transparent conductive layer made of transparent conductive oxide (TCO) material. The thermosensitive dimming layer is made of thermochromic inorganic phase change material, thermochromic organic phase change material or thermochromic inorganic / organic phase change material, and the thermosensitive dimming layer is superimposed on the upper surface of the light-transmitting substrate assembly. The micro-topological triboelectric layer consists of a thin film and a metal electrode. The thin film is made of a fluoropolymer material and is superimposed on the upper surface of the temperature-sensitive dimming layer. The metal electrode is attached to the surface of the thin film to convert the kinetic energy generated by raindrop impact into electrical energy and collect it.

[0008] Furthermore, the transparent conductive oxide material is selected from ITO (indium-doped tin oxide) or FTO (fluorine-doped tin oxide), etc.

[0009] Furthermore, the sheet resistance of the transparent conductive layer is not greater than 15Ω / □, and the visible light transmittance of the transparent conductive layer is greater than or equal to 85%.

[0010] Furthermore, the thermochromic inorganic phase change material includes, but is not limited to, vanadium dioxide-based materials (VO2), tungsten-doped vanadium dioxide (W-VO2), or perovskite materials (A4BX6·2H2O).

[0011] Furthermore, the chemical formula of the perovskite material is A4BX6·2H2O, where A is selected from CH3NH3. + or CH(NH2)2 + B is selected from any one of Pb²⁺, Sn²⁺, Ge²⁺, Mg²⁺ and Ca²⁺, and X is selected from any one or more combinations of I⁻, Br⁻ and Cl⁻.

[0012] Furthermore, the thermochromic organic phase change material is selected from thermochromic hydrogels such as poly(N-isopropylacrylamide) (PNIPAM) or poly(N-vinylcaprolactam) (PNVCL).

[0013] Furthermore, the fluoropolymer is selected from any one of polytetrafluoroethylene (PTFE), fluorinated ethylene propylene copolymer (FEP), and ethylene-tetrafluoroethylene copolymer (ETFE).

[0014] Furthermore, the metal electrode is a platinum electrode, a copper electrode, or an aluminum electrode.

[0015] Furthermore, the thickness of the thin film is 20-50 μm, and the width of the metal electrode is 1 mm.

[0016] A method for preparing the above-mentioned raindrop-powered color-changing smart window includes the following steps: Step 1) Clean the transparent substrate perovskite material made of glass or flexible PET, and deposit a transparent conductive layer perovskite material film on the surface of the cleaned transparent substrate perovskite material to obtain the perovskite material of the light-transmitting substrate component. Step 2) A temperature-sensitive light-tuning layer perovskite material is prepared on the upper surface of the perovskite material of the light-transmitting substrate component using thermochromic inorganic phase change material, thermochromic organic phase change material or thermochromic inorganic / organic phase change material. Step 3) Coat a thin film of perovskite material made of fluoropolymer onto the prepared temperature-sensitive dimming layer perovskite material, and attach a metal electrode perovskite material to the surface of the thin film perovskite material to obtain a micro-topological triboelectric perovskite material. Step 4) The perovskite material of the light-transmitting substrate component, the perovskite material of the temperature-sensitive dimming layer, and the perovskite material of the micro-topology triboelectric layer are cured to finally obtain the color-changing smart window that can generate electricity from raindrops.

[0017] Furthermore, in step 1, the specific method for preparing the perovskite material of the transparent substrate assembly is as follows: First, the transparent substrate perovskite material made of glass or flexible PET is cleaned in an ultrasonic cleaning tank with detergent, ethanol and deionized water (DI water) for 15 minutes, then dried with nitrogen (N2) and further cleaned in a plasma cleaner for 200 seconds. Finally, a dual-cathode magnetron sputtering system is used to deposit ITO (indium-doped tin oxide) or FTO (fluorine-doped tin oxide) on the cleaned transparent substrate perovskite material surface in an Ar / O2 mixed atmosphere (ratio 9:1) to form a transparent conductive perovskite material layer. The sheet resistance of the transparent conductive perovskite material layer is controlled to be ≤15Ω and the visible light transmittance is ≥85%.

[0018] Furthermore, in step 2, the specific method for preparing the temperature-sensitive light-tuning layer perovskite material using a thermochromic inorganic phase change material such as vanadium dioxide-based material (VO2) / tungsten-doped vanadium dioxide (W-VO2) is as follows: First, VO2 / (W-VO2 nanoparticles, PDMS, PMMA precursors and curing agent are mixed with hexane and stirred with a magnetic stirrer to form a mixture; The concentration of aggregated VO2 / W-VO2 nanoparticles in the mixture is then reduced by ultrasonic treatment and / or a settling process. Finally, the mixture is spin-coated onto the upper surface of the perovskite material of the transparent substrate assembly and cured in an oven at 100°C to form a VO2 / W-VO2 thin film.

[0019] Furthermore, in step 2, the specific method for preparing the temperature-sensitive light-tuning layer perovskite material using a thermochromic inorganic phase change material such as perovskite (A4BX6·2H2O) is as follows: First, AX and BX2 are mixed in a dimethylformamide (DMF) or dimethyl sulfoxide (DMSO) solvent at a molar ratio of 4:1 to 7:1, and then stirred at 50-60°C for about 1 hour to prepare a thermochromic perovskite precursor solution. Finally, the prepared thermochromic perovskite precursor solution was spin-coated onto the upper surface of the perovskite material of the transparent substrate assembly. The spin-coating speed was 1000-3000 rpm, the time was 30 s, and the mixture was annealed at 100°C. Wherein, A is a monovalent organic cation selected from CH3NH3. + or CH(NH2)2 + B is any one of the following, where B is a divalent cation selected from Pb²⁺, Sn²⁺, Ge²⁺, Mg²⁺, and Ca²⁺, and X is a halide selected from any one or more combinations of I⁻, Br⁻, and Cl⁻.

[0020] Furthermore, in step 2, the specific method for preparing the temperature-sensitive light-tuning layer perovskite material using a thermochromic organic phase change material such as poly(N-isopropylacrylamide) (PNIPAM) or poly(N-vinylcaprolactam) (PNVCL) is as follows: First, 0.88 mmol of PNIPAM / PNVCL monomer and 0.91 μmol of crosslinking agent BisAA were dissolved in 1 mL of water to form a pregel solution; The pregel solution is then degassed under vacuum to remove dissolved oxygen. Subsequently, 8.9 μmol of photoinitiator KGA was added to the pregel solution and immediately injected into the cavity between the bilayer substrates; Next, it was irradiated with 365nm ultraviolet light in a nitrogen atmosphere for 20 minutes to achieve photocrosslinking and solidify to form PNIPAM / PNVCL hydrogel; Finally, the double-layer substrate is removed, and the formed PNIPAM / PNVCL hydrogel is attached to the surface of the light-transmitting substrate assembly.

[0021] Furthermore, in step 3, the specific method for preparing the perovskite material of the micro-topological triboelectric layer is as follows: First, by drop coating, any one of polytetrafluoroethylene, fluorinated ethylene propylene copolymer, ethylene-tetrafluoroethylene copolymer solution or film is directly deposited on the temperature-sensitive light-tuning perovskite material, thereby completing the fluoropolymer microstructure molding and forming the thin film perovskite material, and controlling the thickness of the film to be 20-50μm; Then, a 1mm wide platinum, copper, or aluminum tape is applied to the surface of the thin-film perovskite material to complete the electrode construction.

[0022] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. Possesses ambient light response dimming capability: This invention utilizes thermochromic materials to construct a temperature-sensitive light-modulating layer, which automatically adjusts the transmittance of visible and near-infrared light according to changes in ambient temperature, thereby improving the indoor light and heat environment. Under high-temperature conditions, the window transmittance decreases significantly, helping to block solar radiation; under low-temperature conditions, the transmittance increases, which is beneficial for passive lighting and heating. The prepared sample achieves a spectral modulation rate of over 50% between 30℃ and 70℃, with visible light transmittance varying from 20% to 90%.

[0023] 2. Achieving the electrical energy conversion of raindrop kinetic energy: This invention integrates a microstructured triboelectric layer on the surface of a window, enabling energy harvesting from the mechanical energy generated by raindrop impacts. Under simulated moderate rain conditions, the system output voltage remains stable, and the power density per unit area can reach 66 W / m². 2 It can provide auxiliary power for low-power electronic components or window control systems, and improve the stability of the device under various climatic conditions.

[0024] 3. Simple structural integration and stable material system: The composite coating material used in this invention can be prepared by a solution method, which is simple and suitable for coating large areas of glass or flexible substrates, demonstrating good engineering feasibility. The device exhibits stable optical response and energy output under alternating heating and cooling, high humidity, and rain conditions, demonstrating good environmental adaptability and service life.

[0025] 4. Possesses potential for application expansion: The technical solution of this invention can be applied to building windows, curtain wall systems, transportation glass, and other scenarios, and has certain prospects for promotion, which helps to improve the energy efficiency and intelligence of buildings.

[0026] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it according to the contents of the specification, the preferred embodiments of the present invention are described in detail below with reference to the accompanying drawings. Specific embodiments of the present invention are given in detail below with reference to the accompanying drawings. Attached Figure Description

[0027] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings: Figure 1 This is a schematic diagram of the structure of the color-changing smart window that can generate electricity from raindrops according to the present invention.

[0028] Figure 2 The transmittance spectra of the sample at 20℃ and 40℃ are shown in the performance test of the temperature-sensitive dimming layer in Example 1 of this invention.

[0029] Figure 3 This is a graph showing the highest voltage result generated by a single raindrop impact in the triboelectric power generation performance test of Embodiment 1 of the present invention.

[0030] Figure 4 This is a graph showing the voltage results generated by continuous 10-second raindrop impact, as demonstrated in the triboelectric power generation performance test of Embodiment 1 of the present invention. Detailed Implementation

[0031] The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings to provide a clearer understanding of the invention's purpose, features, and advantages. It should be understood that the embodiments shown in the drawings are not intended to limit the scope of the invention, but are merely illustrative of the essential spirit of the invention's technical solution.

[0032] In the following description, certain specific details are set forth for the purpose of illustrating various disclosed embodiments in order to provide a thorough understanding of the various disclosed embodiments. However, those skilled in the art will recognize that embodiments may be practiced without one or more of these specific details. In other instances, well-known apparatuses, structures, and techniques associated with this application may not have been shown or described in detail to avoid unnecessarily obscuring the description of the embodiments.

[0033] Unless the context requires otherwise, throughout the specification and claims, the word “comprising” and its variations, such as “including” and “having”, shall be understood to have an open, inclusive meaning, that is, to be interpreted as “including, but not limited to”.

[0034] Throughout this specification, references to "an embodiment" or "an embodiment" indicate that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Therefore, the appearance of "in an embodiment" or "an embodiment" in various places throughout the specification does not necessarily refer to the same embodiment. Furthermore, a particular feature, structure, or characteristic may be combined in any manner in one or more embodiments.

[0035] The singular forms “a” and “the” used in this specification and the appended claims include plural references unless otherwise expressly stated herein. It should be noted that the term “or” is generally used to mean “and / or” unless otherwise expressly stated herein.

[0036] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0037] See Figure 1 As shown, the present invention provides a color-changing smart window that can generate electricity from raindrops, mainly comprising a light-transmitting substrate assembly 1, a temperature-sensitive dimming layer 2, and a micro-topological triboelectric layer 3 stacked sequentially from bottom to top.

[0038] The main body of the light-transmitting substrate assembly 1 is a transparent substrate 11 made of glass or flexible PET. The surface of the transparent substrate 11 is coated with a transparent conductive layer 12 made of a transparent conductive oxide (TCO) material. The transparent conductive oxide material can be ITO (indium-doped tin oxide) or FTO (fluorine-doped tin oxide), etc. The sheet resistance of the transparent conductive layer 12 is not greater than 15 Ω / □, and the visible light transmittance is greater than or equal to 85%.

[0039] The temperature-sensitive dimming layer 2 is superimposed on the upper surface of the light-transmitting substrate assembly 1. The temperature-sensitive dimming layer 2 is made of thermochromic inorganic phase change material, thermochromic organic phase change material, or thermochromic inorganic / organic phase change material.

[0040] The thermochromic inorganic phase change material includes, but is not limited to, vanadium dioxide-based materials (VO2), tungsten-doped vanadium dioxide (W-VO2), or perovskite materials (A4BX6·2H2O).

[0041] The chemical formula of the perovskite material is A4BX6·2H2O, where A is selected from CH3NH3. + or CH(NH2)2 + B is selected from any one of Pb²⁺, Sn²⁺, Ge²⁺, Mg²⁺ and Ca²⁺, and X is selected from any one or more combinations of I⁻, Br⁻ and Cl⁻.

[0042] The thermochromic organic phase change material can be selected from thermochromic hydrogels such as poly(N-isopropylacrylamide) (PNIPAM) or poly(N-vinylcaprolactam) (PNVCL).

[0043] The micro-topological triboelectric layer 3 is composed of a thin film 31 and a metal electrode 32. The thin film 31 is superimposed on the upper surface of the temperature-sensitive dimming layer 2 and is made of a fluoropolymer material. The fluoropolymer is selected from any one of polytetrafluoroethylene (PTFE), fluorinated ethylene propylene copolymer (FEP), and ethylene-tetrafluoroethylene copolymer (ETFE), and has a thickness of 20-50 μm. The metal electrode 32 is a platinum electrode, copper electrode, or aluminum electrode, with a width of 1 mm, and is attached to the surface of the thin film 31 to convert the kinetic energy generated by raindrop impact into electrical energy and collect it.

[0044] The present invention also provides a method for preparing the above-mentioned raindrop-powered color-changing smart window, comprising the following steps: Step 1) Clean the transparent substrate 11 made of glass or flexible PET, and deposit a transparent conductive layer 12 on the surface of the cleaned transparent substrate 11 to obtain the light-transmitting substrate assembly 1. The specific method is as follows: First, a transparent substrate 11 made of glass or flexible PET is cleaned in an ultrasonic cleaning tank with detergent, ethanol, and deionized water (DI water) for 15 minutes, then dried with nitrogen (N2), and further cleaned in a plasma cleaner for 200 seconds. Finally, using a dual-cathode magnetron sputtering system, ITO (indium-doped tin oxide) or FTO (fluorine-doped tin oxide) is deposited on the surface of the cleaned transparent substrate 11 in an Ar / O2 mixed atmosphere (ratio 9:1) to form a transparent conductive layer 12, and the sheet resistance of the transparent conductive layer 12 is controlled to be ≤15Ω and the visible light transmittance is ≥85%.

[0045] Step 2) A temperature-sensitive dimming layer 2 is prepared on the upper surface of the light-transmitting substrate assembly 1 using a thermochromic inorganic phase change material, a thermochromic organic phase change material, or a thermochromic inorganic / organic phase change material.

[0046] The thermochromic inorganic phase change material includes, but is not limited to, vanadium dioxide-based materials (VO2), tungsten-doped vanadium dioxide (W-VO2), or perovskite materials (A4BX6·2H2O).

[0047] The thermochromic organic phase change material can be selected from thermochromic hydrogels such as poly(N-isopropylacrylamide) (PNIPAM) or poly(N-vinylcaprolactam) (PNVCL).

[0048] The specific method for preparing the temperature-sensitive dimming layer 2 using vanadium dioxide-based material (VO2) / tungsten-doped vanadium dioxide (W-VO2) is as follows: First, VO2 / (W-VO2) nanoparticles, PDMS, PMMA precursors and curing agents are mixed with hexane and stirred with a magnetic stirrer to form a mixture. Then, the concentration of VO2 / W-VO2 nanoparticles aggregated in the mixture is reduced by ultrasonic treatment and / or a settling process. Finally, the mixture is spin-coated onto the upper surface of the light-transmitting substrate assembly 1 and cured in an oven at 100°C to form a VO2 / W-VO2 thin film.

[0049] The specific method for preparing the temperature-sensitive dimming layer 2 using perovskite material (A4BX6·2H2O) is as follows: First, AX and BX2 are mixed in a dimethylformamide (DMF) or dimethyl sulfoxide (DMSO) solvent at a molar ratio of 4:1-7:1, and then stirred at 50-60°C for about 1 hour to prepare a thermochromic perovskite precursor solution. Finally, the prepared thermochromic perovskite precursor solution is spin-coated onto the upper surface of the light-transmitting substrate assembly 1 at a spin-coating speed of 1000-3000 rpm for 30 seconds, followed by annealing at 100°C. Wherein, A is a monovalent organic cation selected from CH3NH3. + or CH(NH2)2 + B is any one of the following, where B is a divalent cation selected from Pb²⁺, Sn²⁺, Ge²⁺, Mg²⁺, and Ca²⁺, and X is a halide selected from any one or more combinations of I⁻, Br⁻, and Cl⁻.

[0050] The specific method for preparing the temperature-sensitive dimming layer 2 using poly(N-isopropylacrylamide) (PNIPAM) or poly(N-vinylcaprolactam) (PNVCL) is as follows: First, 0.88 mmol of PNIPAM / PNVCL monomer and 0.91 μmol of crosslinking agent BisAA were dissolved in 1 mL of water to form a pregel solution. Then, the pregel solution was degassed under vacuum to remove dissolved oxygen. Subsequently, 8.9 μmol of photoinitiator KGA was added to the pregel solution and immediately injected into the cavity of the bilayer substrate. Next, it was irradiated with 365 nm ultraviolet light in a nitrogen atmosphere for 20 minutes to achieve photocrosslinking and solidify to form PNIPAM / PNVCL hydrogel. Finally, the bilayer substrate was removed and the formed PNIPAM / PNVCL hydrogel was attached to the surface of the light-transmitting substrate assembly 1.

[0051] Step 3) A thin film 31 made of fluoropolymer is coated onto the prepared temperature-sensitive dimming layer 2, and a metal electrode 32 is attached to the surface of the thin film 31 to obtain the micro-topological triboelectric layer 3. The specific method is as follows: First, a solution or film of polytetrafluoroethylene, fluorinated ethylene propylene copolymer, or ethylene-tetrafluoroethylene copolymer is directly deposited onto the temperature-sensitive dimming layer 2 using a drop-coating method, thereby completing the microstructure formation of the fluoropolymer and forming the thin film 31, with the thickness of the thin film controlled to be 20-50 μm; then, a 1 mm wide platinum, copper, or aluminum tape is attached to the surface of the thin film 31, thereby completing the construction of the electrode.

[0052] Step 4) The light-transmitting substrate assembly 1, the temperature-sensitive dimming layer 2 and the micro-topology triboelectric layer 3 are cured to finally obtain the raindrop-generating color-changing smart window.

[0053] The following two examples illustrate the preparation method of the present invention and the performance of the obtained smart window. Example 1

[0054] 1. Device fabrication process: 1) Cleaning and pretreatment of light-transmitting substrate assembly PET was selected as the transparent substrate. It was ultrasonically cleaned for 10 minutes with anhydrous ethanol and deionized water respectively. After drying, it was placed in a plasma cleaner for 120 seconds to enhance surface activity and adhesion of subsequent materials.

[0055] 2) Deposition of transparent conductive layer A transparent substrate assembly is fabricated by depositing an ITO or FTO film of approximately 80 nm thickness on the surface of a PET transparent substrate using room temperature magnetron sputtering. The sheet resistance of the ITO or FTO film is controlled to be ≤30 Ω and the transmittance is ≥80%, ensuring the compatibility of its conductivity and optical performance on the flexible substrate.

[0056] 3) Construction of PNIPAM hydrogel temperature-sensitive light-tuning layer N-Isopropylacrylamide (NIPAM, 0.88 mmol) and crosslinking agent N,N'-methylenebisacrylamide (BisAA, 0.91 μmol) were dissolved in 1 mL of deionized water to prepare a pregel solution. This pregel solution was degassed under vacuum for 10 minutes to remove dissolved oxygen. Then, photoinitiator KGA (8.9 μmol) was added, mixed thoroughly, and rapidly injected into the parallel gaps between the bilayer substrates. The entire encapsulation structure was crosslinked and cured under 365 nm UV light for 20 minutes to obtain a PNIPAM hydrogel layer with a thickness of approximately 200 μm. Finally, the bilayer substrate was removed, and the PNIPAM hydrogel layer was adhered to the surface of the previously prepared transparent substrate assembly.

[0057] 4) Assembly of micro-topological triboelectric layer A 25 μm thick FEP film was used to cover the surface of the PNIPAM hydrogel layer prepared in the previous step, and it was fixed by physical bonding and local hot pressing. Two 1 mm wide copper foil electrodes were attached to the outside of the FEP film and connected to an external data acquisition system through wires to construct a complete raindrop power generation circuit.

[0058] 2. Performance Testing Methods and Results 1) Temperature-sensitive dimming performance test The transmittance spectrum changes of the samples prepared in this embodiment were measured using a visible-near-infrared spectrophotometer under different temperature conditions (20°C and 40°C). See also Figure 2 As shown, the results indicate that at high temperatures, the PNIPAM gel undergoes hydrophobic collapse, leading to enhanced light scattering and a decrease in window transmittance to approximately 20%. Conversely, at low temperatures, the gel structure expands, increasing transparency and transmittance to approximately 91%. The thermo-sensitive dimming performance test results demonstrate that the sample prepared in this embodiment exhibits significant reversibility and thermo-sensitive dimming response.

[0059] 2) Triboelectric power generation performance test The electrical output performance of the sample prepared in this embodiment was determined using a raindrop test platform. See [link to relevant documentation]. Figure 3 and Figure 4 As shown in the figure, experiments demonstrate that the power density per unit area of ​​the sample prepared in this embodiment can reach 66 W / m². 2 The peak voltage generated by a single raindrop impact is approximately 207V, and it has the ability to harvest energy with a continuous and stable voltage output. Example 2

[0060] 1. Device fabrication process 1) Cleaning and pretreatment of light-transmitting substrate assembly Select an optical glass substrate with a standard thickness of 1.1 mm, and clean it in an ultrasonic cleaning tank for 15 minutes in sequence with neutral detergent, ethanol and deionized water. After drying, treat it in a plasma cleaner for 200 seconds to improve surface affinity.

[0061] 2) Deposition of transparent conductive layer A transparent conductive film such as ITO or FTO is deposited on the surface of an optical glass substrate using a dual-target magnetron sputtering system in an atmosphere of mixed argon and oxygen (volume ratio 9:1). The thickness of the ITO or FTO transparent conductive film is controlled to be about 100 nm, the sheet resistance is ≤15Ω, and the light transmittance is ≥85%, thereby producing a transparent substrate assembly.

[0062] 3) Construction of thermochromic perovskite dimming layer Preparation of thermochromic perovskite precursor solution: Dissolve AX (A is CH3NH3Cl) and BX2 (B is PbI2) in dimethylformamide (DMF) at a molar ratio of 6:1 to a concentration of about 1 mol / L. Stir at 50°C for 60 minutes to obtain a clear precursor solution.

[0063] A precursor solution was uniformly coated onto the surface of a transparent substrate assembly using a spin-coating process (2000 rpm, 30 s), followed by annealing on a hot plate at 100°C for 10 minutes to form a dense thermochromic perovskite film (approximately 400 nm thick). This film exhibits reversible visible light modulation capability at different temperatures.

[0064] 4) Assembly of micro-topological triboelectric layer A pre-prepared PTFE solution was coated onto the surface of a thermochromic perovskite film and cured by heating. A 1 mm wide copper foil electrode was then attached to the PTFE surface for energy harvesting output. The electrode leads were connected to an external charge harvesting device, completing the overall device construction.

[0065] 2. Performance Testing Methods and Results 1) Photochromic response performance test The samples prepared in this embodiment had their transmission spectra measured using a UV-Vis-NIR spectrophotometer at 30°C and 70°C. The results showed that the visible light transmittance of the dimming window decreased by approximately 50% at high temperatures, exhibiting significant thermal response dimming characteristics and good modulation efficiency.

[0066] 2) Raindrop power generation performance test Using the same raindrop impact testing platform as in Example 1, the triboelectric output performance of the sample prepared in this example was measured under simulated moderate rain intensity. Experiments showed that the maximum output power density per unit area of ​​the sample was 59 W / m². 2 The voltage peak generated by a single raindrop impact reaches 55 V, indicating that it has a stable energy conversion capability.

[0067] In summary, this invention provides a color-changing smart window capable of generating electricity from raindrops. By integrating a temperature-sensitive color-changing functional layer and a triboelectric power generation structural layer, it achieves synergistic functions of optical control and raindrop energy harvesting. This smart window not only continuously and effectively changes its color tone under different climatic conditions (including sunny and rainy days) and possesses dynamic control over photothermal characteristics, but also efficiently recovers the energy generated by raindrop impacts. This allows the smart window to maintain efficient energy harvesting and energy-saving functions even on rainy days, reducing building air conditioning energy consumption and improving overall building energy efficiency.

[0068] Therefore, this invention solves the problems of existing thermochromic smart window technology failing to operate continuously in rainy weather, its intelligent dimming function failing, resulting in the inability to achieve continuous energy saving in multiple climate scenarios, and the failure to effectively recover the kinetic energy generated by rainwater impacting the window, thus forming an energy breakpoint in the energy-saving technology chain.

[0069] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A smart window with color-changing lighting that generates electricity from raindrops, characterized in that: It includes a light-transmitting substrate assembly (1), a temperature-sensitive dimming layer (2), and a micro-topology triboelectric layer (3). The main body of the light-transmitting substrate assembly (1) is a transparent substrate (11) made of glass or flexible PET, and the surface of the transparent substrate (11) is coated with a transparent conductive layer (12) made of ITO or FTO. The thermosensitive dimming layer (2) is superimposed on the upper surface of the light-transmitting substrate assembly (1). The thermosensitive dimming layer (2) is made of thermochromic inorganic phase change material, thermochromic organic phase change material, or thermochromic inorganic / organic phase change material. The thermochromic inorganic phase change material is selected from vanadium dioxide-based material, tungsten-doped vanadium dioxide, or perovskite material. The thermochromic organic phase change material is selected from poly(N-isopropylacrylamide) hydrogel or poly(N-vinylcaprolactam) hydrogel. The micro-topological triboelectric layer (3) is composed of a thin film (31) and a metal electrode (32); the thin film (31) is superimposed on the upper surface of the temperature-sensitive dimming layer (2), and the thin film (31) is made of a fluoropolymer material, which is selected from any one of polytetrafluoroethylene, fluorinated ethylene propylene copolymer, and ethylene-tetrafluoroethylene copolymer; the metal electrode (32) is attached to the surface of the thin film (31) to convert the kinetic energy generated by the impact of raindrops into electrical energy and collect it.

2. The color-changing smart window capable of generating electricity from raindrops according to claim 1, characterized in that: The sheet resistance of the transparent conductive layer (12) is not greater than 15Ω / □, and the visible light transmittance of the transparent conductive layer (12) is greater than or equal to 85%.

3. The color-changing smart window capable of generating electricity from raindrops according to claim 1, characterized in that: The chemical formula of the perovskite material is A4BX6·2H2O, where A is selected from CH3NH3. + or CH(NH2)2 + B is selected from any one of Pb²⁺, Sn²⁺, Ge²⁺, Mg²⁺ and Ca²⁺, and X is selected from any one or more combinations of I⁻, Br⁻ and Cl⁻.

4. The color-changing smart window capable of generating electricity from raindrops according to claim 1, characterized in that: The metal electrode is a platinum electrode, a copper electrode, or an aluminum electrode.

5. The color-changing smart window capable of generating electricity from raindrops according to claim 1, characterized in that: The thickness of the thin film is 20-50 μm, and the width of the metal electrode is 1 mm.

6. A method for preparing a color-changing smart window capable of generating electricity from raindrops as described in any one of claims 1-5, characterized in that, Includes the following steps: Step 1) Clean the transparent substrate (11) made of glass or flexible PET, and deposit a transparent conductive layer (12) on the surface of the cleaned transparent substrate (11) to obtain a light-transmitting substrate assembly (1). Step 2) A temperature-sensitive dimming layer (2) is prepared on the upper surface of the light-transmitting substrate assembly (1) using a thermochromic inorganic phase change material, a thermochromic organic phase change material, or a thermochromic inorganic / organic phase change material. Step 3) Coat a thin film (31) made of fluoropolymer on the prepared temperature-sensitive dimming layer (2), and attach a metal electrode (32) to the surface of the thin film (31) to obtain a micro-topological triboelectric layer (3). Step 4) The light-transmitting substrate assembly (1), the temperature-sensitive dimming layer (2) and the micro-topology triboelectric layer (3) are cured to finally obtain the raindrop-generating color-changing smart window.

7. The preparation method according to claim 1, characterized in that, In step 1, the specific method for preparing the light-transmitting substrate assembly (1) is as follows: First, the transparent substrate (11) made of glass or flexible PET is cleaned in an ultrasonic cleaning tank with detergent, ethanol and deionized water for 15 minutes, then dried with nitrogen, and then further cleaned in a plasma cleaner for 200 seconds. Finally, a dual-cathode magnetron sputtering system is used to deposit ITO or FTO on the cleaned transparent substrate (11) in an Ar / O2 mixed atmosphere to form a transparent conductive layer (12), and the sheet resistance of the transparent conductive layer (12) is controlled to be ≤15Ω and the visible light transmittance is ≥85%.

8. The preparation method according to claim 1, characterized in that, In step 1, the specific method for preparing the temperature-sensitive dimming layer (2) using a thermochromic inorganic phase change material is as follows: 1) Vanadium dioxide-based materials / Tungsten-doped vanadium dioxide: First, vanadium dioxide-based materials / tungsten-doped vanadium dioxide nanoparticles, PDMS, PMMA precursors and curing agents are mixed with hexane and stirred with a magnetic stirrer to form a mixture. The concentration of vanadium dioxide-based materials / tungsten-doped vanadium dioxide nanoparticles aggregated in the mixture is then reduced by ultrasonic treatment and / or settling. Finally, the mixture is spin-coated onto the upper surface of the light-transmitting substrate assembly (1) and cured in an oven at 100°C to form a vanadium dioxide-based / tungsten-doped vanadium dioxide thin film. 2) Perovskite materials: First, AX and BX2 are mixed in a solvent of dimethylformamide or dimethyl sulfoxide at a molar ratio of 4:1 to 7:1, and then stirred at 50-60°C for about 1 hour to prepare a thermochromic perovskite precursor solution. Finally, the prepared thermochromic perovskite precursor solution was spin-coated onto the upper surface of the light-transmitting substrate assembly (1) at a spin speed of 1000-3000 rpm for 30 s and then annealed at 100°C. Wherein, A is a monovalent organic cation selected from CH3NH3. + or CH(NH2)2 + B is any one of the following, where B is a divalent cation selected from Pb²⁺, Sn²⁺, Ge²⁺, Mg²⁺, and Ca²⁺, and X is a halide selected from any one or more combinations of I⁻, Br⁻, and Cl⁻.

9. The preparation method according to claim 1, characterized in that, In step 1, the specific method for preparing the temperature-sensitive dimming layer (2) using a thermochromic organic phase change material is as follows: First, 0.88 mmol of poly(N-isopropylacrylamide) or poly(N-vinylcaprolactam) monomer and 0.91 μmol of crosslinking agent BisAA were dissolved in 1 mL of water to form a pregel solution. The pregel solution is then degassed under vacuum to remove dissolved oxygen. Subsequently, 8.9 μmol of photoinitiator KGA was added to the pregel solution and immediately injected into the cavity between the bilayer substrates; Next, it was irradiated with 365nm ultraviolet light in a nitrogen atmosphere for 20 minutes to achieve photocrosslinking and solidify into a poly(N-isopropylacrylamide / poly(N-vinylcaprolactam)) hydrogel. Finally, the double-layer substrate is removed, and the formed poly(N-isopropylacrylamide / poly(N-vinylcaprolactam)) hydrogel is attached to the surface of the light-transmitting substrate assembly (1).

10. The preparation method according to claim 1, characterized in that, In step 1, the specific method for preparing the micro-topological triboelectric layer (3) is as follows: First, by drop coating, any one of polytetrafluoroethylene, fluorinated ethylene propylene copolymer, ethylene-tetrafluoroethylene copolymer solution or film is directly deposited on the temperature-sensitive light-adjusting layer (2) to complete the fluoropolymer microstructure molding and form the film (31), and the thickness of the film is controlled to be 20-50μm; Then a 1mm wide platinum, copper or aluminum tape is applied to the surface of the thin film (31) to complete the construction of the electrode.

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