Transparent photo-thermal driving flexible wet pump material and preparation method and application thereof

Abstract

The invention discloses a transparent photo-thermal driving flexible wet pump material as well as a preparation method and application thereof, and belongs to the technical field of air humidity regulation and energy-saving building materials. The transparent photo-thermal driving flexible wet pump material prepared by the invention is a transparent material, does not block outdoor light from irradiating indoors when being used, and does not influence the lighting capacity of a house; and meanwhile, due to the flexible material, when not in use, the clothes hanger can be rolled up and stored, and does not occupy space. The transparent photo-thermal driving flexible wet pump material prepared by the invention can realize one-way transfer of water from indoor to outdoor, can realize transfer of water from high humidity to low humidity, can also realize transfer of water from low humidity to high humidity, and passively reduces the indoor humidity of a building. According to the transparent photo-thermal driving flexible wet pump material, photo-thermal conversion is conducted through the efficient photo-thermal particles, the temperature of the composite material can be rapidly increased within a short time, and therefore absorbed water can be rapidly desorbed, and zero-energy-consumption regeneration is achieved.

Description

A transparent photothermal driven flexible wet pump material, its preparation method and application Technical Field

[0001] This invention belongs to the field of air humidity regulation and energy-saving building materials technology, specifically relating to a transparent photothermal driven flexible wet pump material, its preparation method, and its application. Background Technology

[0002] Air humidity has a significant impact on daily life and production. In daily life, indoor humidity is closely related to human health. The optimal indoor relative humidity for human thermal comfort is 40%–60%. High humidity environments promote the growth of bacteria and other microorganisms, leading to a series of related diseases. In industrial production, high humidity environments can cause corrosion of metal machinery, electronic components, and precision instruments, seriously affecting product quality and creating safety hazards. Therefore, effective air dehumidification is becoming increasingly important in modern industrial and agricultural production as well as in people's daily lives.

[0003] Relevant statistics show that energy consumption caused by moisture load accounts for 43% of building operating energy consumption. In industrial production, the energy consumption for creating a low-humidity environment is even more significant. In lithium battery factories, air conditioning energy consumption accounts for 34% of total energy consumption, with dehumidifying air conditioning accounting for 62% of that. Therefore, improving the "self-breathing" passive humidity management capabilities of building envelopes, thereby reducing the energy consumption and carbon emissions of active humidity control equipment, is of great importance.

[0004] Solid adsorbent dehumidification is a common passive humidity control method. Its principle is to absorb moisture from the air using the adsorption properties of the inner and outer surfaces of porous solid desiccant materials. Composite solid desiccant materials can compensate for the shortcomings of single materials, thus exhibiting more ideal dynamic moisture absorption and regeneration performance. However, most composite desiccant materials currently under research operate in an intermittent mode, meaning the moisture absorption and regeneration processes occur intermittently. Once the desiccant material reaches saturation, the absorption process needs to be stopped, and a heater is used for regeneration. Therefore, low-power continuous dehumidification cannot be achieved. Furthermore, most composite desiccant materials are opaque and inflexible, making it impossible to simultaneously achieve light transmission and easy storage. Summary of the Invention

[0005] The purpose of this invention is to provide a transparent photothermal driven flexible humidity pump material, its preparation method, and its application, to overcome the shortcomings of existing modified composite humidity-regulating materials that are opaque and lack flexibility. The transparent photothermal driven flexible humidity pump material prepared by this invention utilizes solar energy for interfacial evaporation, achieving continuous unidirectional moisture transfer and passively reducing indoor humidity in buildings.

[0006] To achieve the above objectives, the present invention provides the following technical solutions: One of the technical solutions of the present invention is a method for preparing a transparent photothermal driven flexible wet pump material, comprising the following steps: mixing tetraethyl orthosilicate, KH570 silane coupling agent, ethanol and water, adjusting the pH of the system to 3-4 with acid, hydrolyzing to obtain sol A, adding polymethyl methacrylate microspheres and polyethylene glycol mother liquor to sol A, mixing evenly to obtain sol B, pouring sol B into a mold for gelation, and then adding lithium chloride. The solution undergoes solvent displacement, followed by the removal of unreacted substances using acetone to obtain hydrophobic wet gel A. Tetraethyl orthosilicate, KH570 silane coupling agent, ethanol, and water are mixed, and the pH of the system is adjusted to 3-4 with acid. After hydrolysis, sol C is obtained. Polymethyl methacrylate microspheres, polyethylene glycol methacrylate microspheres, TiO2 nanoparticle mother liquor, and polyethylene glycol mother liquor are added to sol C and mixed thoroughly to obtain sol D. Sol D is poured into a mold for gelation, and then lithium chloride solution is added for further processing. The reaction mixture is replaced with an acetone to remove unreacted substances, yielding a hydrophilic wet gel B. Tetraethyl orthosilicate, methoxytrimethylsilane, ethanol, and water are mixed, and the pH of the system is adjusted to 2.5–3.0 with acid. After hydrolysis, sol E is obtained. Tungsten oxide photothermal particle dispersion, polyethylene glycol methacrylate microspheres, and KH570 silane coupling agent are added to sol E. After thorough mixing, ammonia is added to adjust the pH to 6.0–6.5 for alkali-catalyzed crosslinking, yielding sol F. Sol F is then poured into a mold for further processing. The gel is formed, and then unreacted substances are removed with anhydrous ethanol. A mixed solution of ethanol and n-hexane is added for solvent replacement to obtain photothermal wet gel C. The hydrophobic wet gel A is laid in a mold, frozen and then the hydrophilic wet gel B is added. After drying, a hydrophilic-hydrophobic bilayer silica aerogel is obtained. The photothermal wet gel C is then coated on the hydrophilic side of the hydrophilic-hydrophobic bilayer silica aerogel. After removing the solvent, a transparent photothermal driven flexible wet pump material composed of a hydrophobic layer, a hydrophilic layer and a photothermal layer is obtained.

[0007] Preferably, in the preparation step of the hydrophobic wet gel A, the molar ratio of tetraethyl orthosilicate, KH570 silane coupling agent, ethanol and water is 1:0.3-0.4:10-20:3-5.

[0008] Preferably, in the preparation step of the hydrophobic wet gel A, the amount of polymethyl methacrylate microspheres added is 3-5% of the mass of sol A; the concentration of the polyethylene glycol mother liquor is 60-70% w / v; and the amount of the polyethylene glycol mother liquor added is 2-3% of the mass of sol A.

[0009] Preferably, in the preparation step of the hydrophilic wet gel B, the molar ratio of tetraethyl orthosilicate, KH570 silane coupling agent, ethanol and water is 1:0.15-0.25:10-20:3-5.

[0010] Preferably, in the preparation step of the hydrophilic wet gel B, the amount of polymethyl methacrylate microspheres added is 3-5% of the mass of sol C; the amount of polyethylene glycol methacrylate microspheres added is 2-3% of the mass of sol C; the concentration of the polyethylene glycol mother liquor is 60-70% w / v; the amount of the polyethylene glycol mother liquor added is 1-2% of the mass of sol C; the concentration of the TiO2 nanoparticle mother liquor is 10-20 mg / mL; and the amount of the TiO2 nanoparticle mother liquor added is 1-2% of the mass of sol C.

[0011] Preferably, in the preparation step of the photothermal wet gel C, the molar ratio of tetraethyl orthosilicate, methoxytrimethylsilane, ethanol and water is 1:0.6-0.8:3-5:2-3.

[0012] Preferably, in the preparation step of the photothermal wet gel C, the concentration of the tungsten oxide photothermal particle dispersion is 10-15 mg / mL; the amount of the tungsten oxide photothermal particle dispersion added is 1.5-3% of the mass of the sol E; the amount of the polyethylene glycol methacrylate microspheres added is 2-3% of the mass of the sol E; and the amount of the KH570 silane coupling agent added is 1-2% of the mass of the sol E.

[0013] Preferably, the volume ratio of ethanol to hexane in the mixed solution of ethanol and n-hexane is 1:1.

[0014] Preferably, the thickness ratio of the hydrophobic layer, the hydrophilic layer, and the photothermal layer is 1:3-4:0.4-0.6.

[0015] The second technical solution of the present invention provides a transparent photothermal driven flexible wet pump material prepared according to the above-mentioned preparation method of transparent photothermal driven flexible wet pump material.

[0016] The third technical solution of the present invention provides an application of the above-mentioned transparent photothermal driven flexible wet pump material in the preparation of vortex roller blinds.

[0017] The beneficial technical effects of the present invention are as follows: (1) The transparent photothermal driven flexible wet pump material prepared by the present invention is a transparent material, which will not block outdoor light from shining into the room when in use, and will not affect the lighting capacity of the house.

[0018] (2) The transparent photothermal driven flexible wet pump material prepared by the present invention is a flexible material that can be rolled up and stored when not in use, without taking up space.

[0019] (3) The transparent photothermal driven flexible wet pump material prepared by the present invention can realize the one-way continuous transfer of water from indoors to outdoors. It can transfer water from high humidity to low humidity, and also transfer water from low humidity to high humidity, thus passively reducing the humidity in the building.

[0020] (4) The transparent photothermal driven flexible wet pump material provided by the present invention performs photothermal conversion through efficient photothermal particles, which can quickly increase the temperature of the composite material in a short time, thereby enabling rapid desorption of absorbed moisture and achieving zero-energy regeneration. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. 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 effort.

[0022] Figure 1 is a schematic diagram of the structure of the transparent photothermal driven continuous directional moisture-guiding roller shutter in Example 2.

[0023] Figure 2 is a schematic diagram of the structure of the transparent photothermal driven flexible wet pump material prepared in Example 1.

[0024] Figure 3 is a schematic diagram of the transparent roller blind in Example 2.

[0025] Figure 4 is a schematic diagram of the actual installation of the transparent photothermal driven continuous directional moisture-guiding vortex roller blind prepared in Example 2.

[0026] Figure 5 is a schematic diagram of the closed simulated house experimental system constructed according to the present invention.

[0027] Figure 6 shows the infrared thermographs of the aerogel materials in the experimental and control groups after irradiation for 0 min and 15 min.

[0028] Figure 7 shows the change of relative humidity over time in each simulated house during the continuous dehumidification performance evaluation.

[0029] Figure 8 shows the changes in internal humidity of a simulated house with different initial internal humidity levels under different external humidity levels. In the figure, a represents the changes in internal humidity of a simulated house with an initial internal humidity of 70%RH, and b represents the changes in internal humidity of a simulated house with an initial internal humidity of 50%RH.

[0030] Figure 9 is a schematic diagram of the transparent photothermal driven flexible wet pump material provided by the present invention continuously dehumidifying under photothermal drive.

[0031] In the diagram, 1 is a transparent roller blind, 2 is a vortex roller blind box, 3 is a vortex roller blind guide rail, 4 is a hydrophobic layer of the transparent photothermal driven flexible wet pump material, 5 is a hydrophilic layer of the transparent photothermal driven flexible wet pump material, 6 is a photothermal layer of the transparent photothermal driven flexible wet pump material, 7 is the transparent photothermal driven flexible wet pump material, and 8 is a rubber frame. Detailed Implementation

[0032] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention. It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the present invention.

[0033] It should be noted that any aspects not described in detail in this invention are conventional practices in the field and are not the focus of this invention.

[0034] Furthermore, regarding the numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Any stated value or intermediate value within a stated range, as well as each smaller range between any other stated value or intermediate value within said range, are also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0035] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar to or equivalent to those described herein may be used in the implementation or testing of this invention.

[0036] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.

[0037] Unless otherwise specified, room temperature in this invention refers to a temperature of 20±10℃.

[0038] Example 1: Preparation of hydrophobic wet gel A: ① Sol preparation: Tetraethyl orthosilicate (TEOS): KH570 silane coupling agent: ethanol: deionized water = 1:0.4:15:3 molar ratio, stirred at 300 r / min for 1 h; hydrochloric acid was added dropwise to adjust pH to 3.5, and hydrolysis was carried out at 25℃ for 1.5 h. A transparent silica sol was formed; 5% by weight of silica sol was added to polymethyl methacrylate (PMMA) microspheres, ultrasonically dispersed for 35 min (120 W), and then 3% by weight of silica sol was added to polyethylene glycol (PEG) stock solution (PEG concentration 60% w / v), stirred evenly to obtain the sol. ② Gel and aging: Pour the sol into the mold and let it stand at room temperature for 10 hours to gel; add 5 wt% lithium chloride solution to the mold and perform solvent replacement at room temperature for 12 hours. Then, remove the excess solution from the surface and soak it in acetone for 48 hours, changing the acetone every 8 hours to remove unreacted impurities; remove the acetone to obtain hydrophobic wet gel A.

[0039] Preparation of hydrophilic wet gel B: ① Sol preparation: Mix TEOS:KH570:ethanol:deionized water in a molar ratio of 1:0.2:15:3 and stir at 300 r / min for 1 h; add hydrochloric acid to adjust pH to 3.5, and hydrolyze at 25℃ for 1.5 h to form a transparent silica sol; add 3% PMMA microspheres and 2% polyethylene glycol methacrylate (PEGMA) microspheres by weight of silica sol, and ultrasonically disperse for 35 min (120 W); then add 1.5% PEG stock solution (PEG concentration of 60% w / v) by weight of silica sol and stir for 20 min; add 1.5% TiO2 nanoparticle stock solution (TiO2 concentration of 15 mg / mL) by weight of silica sol, and continue ultrasonic dispersion for 30 min and magnetic stirring for 20 min to obtain the sol. ② Gel and aging: Pour the sol into the mold and let it stand at room temperature for 10 hours to gel; add 5 wt% lithium chloride solution to the mold and perform solvent replacement at room temperature for 12 hours. Then, remove the excess solution from the surface and soak it in acetone for 60 hours, changing the acetone every 8 hours to remove unreacted impurities; remove the acetone to obtain the hydrophilic wet gel B.

[0040] Preparation of photothermal coating wet gel C: ① Sol preparation: First, add two silicon sources to an ethanol aqueous solution at a molar ratio of TEOS:methoxytrimethylsilane (MTMS):ethanol:deionized water = 1:0.7:4:2, stir at 300 r / min for 30 min until homogeneous; add 0.05 mol / L oxalic acid dropwise to adjust the pH of the system to 3.0, and perform acid-catalyzed hydrolysis at 25℃ for 1.5 h to form sol E. ② Photothermal fusion: Slowly add 2% by weight of tungsten oxide (WO3) photothermal particle dispersion (WO3 content is 15 mg / mL) of sol E, and simultaneously sonicate for 20 min. Then add 2% by weight of PEGMA microspheres and 1.5% by weight of sol E of KH570 silane coupling agent, and continue stirring for 30 min; add 0.03 mol / L ammonia dropwise to adjust the pH of the system to 6.5, perform alkali-catalyzed crosslinking for 30 min, and allow to stand for 10 min to mature to obtain sol F. ③ Gel and Aging: Pour sol F into a mold and let it stand at room temperature for 10 hours to gel; soak in anhydrous ethanol for 36 hours, replacing the anhydrous ethanol every 12 hours. Then replace it twice with a 1:1 volume ratio of ethanol and n-hexane solution, each time for 6 hours, and then replace it twice with pure n-hexane to obtain the photothermal coating wet gel C.

[0041] Preparation of a transparent photothermal-driven flexible wet pump material: A hydrophobic wet gel layer A was placed in a mold. The mold was gently vibrated to level the liquid surface and remove air bubbles. The mold was then placed in a freezer for 1 hour to pre-freeze and solidify. Next, a hydrophilic wet gel layer B was poured onto the surface of the frozen gel. After leveling the liquid surface, the mold was placed in the sample chamber of a freeze dryer and frozen at -50°C for 4 hours. Then, it was freeze-dried (-50°C, 0.5 MPa) for 48 hours to prepare a hydrophilic-hydrophobic bilayer silica aerogel (hydrophilic layer thickness 3 mm, hydrophobic layer thickness 1 mm, hydrophilic-hydrophobic layer thickness ratio 3:1). Subsequently, a 0.5 mm thick photothermal coating wet gel C was uniformly coated onto the hydrophilic side of the prepared hydrophilic-hydrophobic bilayer silica aerogel. The aerogel was then placed in a drying oven and heated to 60°C at a rate of 2°C / h, held for 4 hours, and then heated to 80°C and held for 2 hours. The solvent was slowly removed, finally yielding a transparent photothermal-driven flexible wet pump material (structural schematic shown in Figure 2).

[0042] Comparative Example 1: Preparation of a continuous directional humidifying flexible silica aerogel without photothermal drive: The only difference from the preparation method of the transparent photothermal driven flexible wet pump material in Example 1 is that the wet gel C is not coated with a photothermal coating.

[0043] Example 2: A transparent photothermal driven flexible wet pump material of suitable size was cut and prepared according to requirements. A rubber frame was used to encapsulate and fix the material around its perimeter, resulting in a transparent roller shutter (see Figure 3 for a structural schematic). The obtained transparent roller shutter was assembled with a vortex roller shutter box and a vortex roller shutter guide rail to obtain a transparent photothermal driven continuous directional moisture-guiding vortex roller shutter (see Figure 1 for a structural schematic).

[0044] In Figures 1 to 3, 1 is a transparent roller blind, 2 is a vortex roller blind box, 3 is a vortex roller blind guide rail, 4 is a hydrophobic layer of the transparent photothermal driven flexible wet pump material, 5 is a hydrophilic layer of the transparent photothermal driven flexible wet pump material, 6 is a photothermal layer of the transparent photothermal driven flexible wet pump material, 7 is the transparent photothermal driven flexible wet pump material, and 8 is a rubber frame.

[0045] Figure 4 shows a schematic diagram of the actual installation of the transparent photothermal driven continuous directional moisture-guiding roller blind prepared in Example 2.

[0046] As shown in Figure 4, the vortex roller shutter is installed on the exterior wall, with the hydrophobic layer of the transparent photothermal driven flexible wet pump material on the interior side. When the hydrostatic pressure HP is greater than the hydrophobic force HF caused by the capillary pressure on the hydrophobic side, it will drive droplets to break through the hydrophobic layer and migrate towards the hydrophilic matrix. At the same time, the capillary force CF of the hydrophilic layer generates a synergistic adsorption effect, promoting the rapid diffusion of water within the hydrophilic layer. Under the action of the wetting gradient, water is directionally transported to the adjacent hydrophilic layer of the photothermal layer, thereby achieving efficient water evaporation under photothermal drive.

[0047] Conversely, when a droplet comes into contact with a hydrophilic surface, its instantaneous wetting properties (contact angle <10°) cause the liquid to spread rapidly and form a liquid film, resulting in the interface curvature radius approaching infinity. This reduces the hydrostatic pressure difference to a negligible range. Therefore, when the droplet reaches the hydrophilic-hydrophobic interface, the hydrophobic force of the hydrophobic layer completely inhibits the reverse permeation of water.

[0048] To evaluate the performance of the transparent photothermal-driven flexible humidifier material (also a silica aerogel) prepared in Example 1, a closed simulated house experimental system (see Figure 5 for a schematic diagram) was constructed for testing. The testing equipment included a 20cm×20cm×20cm simulated house constructed with XPS insulation panels; a 6cm diameter circular transparent photothermal-driven flexible humidifier material serving as a dehumidification window; a high-precision temperature and humidity monitor and data acquisition device to collect changes in temperature and humidity inside and outside the simulated house; a constant temperature and humidity chamber to simulate external environmental conditions; an adjustable humidifier to simulate the continuous generation of water vapor indoors; and a xenon lamp as a simulated solar light source. The entire testing system was placed inside the large constant temperature and humidity chamber, and different outdoor environmental conditions were simulated by precisely controlling the temperature and humidity parameters inside the chamber. During the experiment, the moisture-absorbing layer of the sample faced the interior of the simulated house, while the photothermal layer faced the external environment. To ensure the reliability of the experimental data, all connection points of the simulated house were strictly sealed. A simulated solar light source was installed above the photothermal layer to provide stable illumination.

[0049] To evaluate the photothermal conversion performance of the transparent photothermal driven flexible wet pump material, a comparative experimental scheme was designed in this invention. A xenon lamp was used as a simulated solar light source (spectral range 300–2500 nm), whose spectral distribution showed good consistency with the AM 1.5G standard solar spectrum. An infrared thermal imaging camera recorded the temperature changes on the surface of the photothermal material. Before the experiment, the transparent photothermal driven flexible wet pump material (experimental group) and a continuous directional moisture-wicking flexible silica aerogel without photothermal drive (control group) were subjected to moisture absorption at 25°C and 70% humidity for eight hours to ensure that the weight of water absorbed by both was consistent. At 1 kW / m³... 2 The materials were irradiated under light intensity, and the infrared thermal images of the aerogel materials in the experimental group and the control group after 0 min and 15 min of irradiation are shown in Figure 6. As shown in Figure 6, the temperatures were almost equal in the first two stages of irradiation. After 15 minutes of irradiation, the average surface temperature of the experimental group reached 53.7℃, while that of the control group was only 38.3℃. This result indicates that the photothermal layer can significantly enhance the photothermal conversion capacity of the aerogel. Furthermore, the color of the temperature patches at various locations on the surface of the experimental group material was relatively consistent, proving that the photothermal material was uniformly distributed on the surface of the hydrophilic layer, forming a photothermal layer with consistent light absorption capacity.

[0050] To systematically evaluate the continuous dehumidification performance of the transparent photothermal driven flexible humidifier material, this invention designed a comparative experimental scheme (control group) and a no-material group. The control group used a continuous directional moisture-guiding flexible silica aerogel without photothermal drive. In the initial stage of the experiment, the humidification rate of the material was dynamically balanced with the indoor moisture generation rate by adjusting the humidifier's output. The relative humidity in the simulated room was stably controlled at approximately 50%RH (±1%). The changes in relative humidity in the simulated rooms over time for each group are shown in Figure 7. In Figure 7, the experimental group used the transparent photothermal driven flexible humidifier material. During the 10-hour test period, the relative humidity inside the simulated room remained consistently around 50%RH (fluctuation range ±2%RH). For the control group, the continuously directional moisture-wicking flexible silica aerogel without photothermal drive function, the humidity inside the simulated house began to deviate from equilibrium and gradually increase after 2 hours of testing. This is because as the moisture absorption process continues, the material's moisture absorption capacity gradually approaches saturation, leading to a continuous decrease in its moisture absorption rate, which eventually cannot match the continuous moisture input rate. After 10 hours of continuous testing, the internal relative humidity had risen to 64.5%, exceeding the human comfort humidity range (40%–60% RH). However, without any moisture-absorbing material, continuous humidification (at the same humidification rate) resulted in an internal humidity of 90% within 5 hours, demonstrating that the transparent photothermal driven flexible moisture pump material has strong moisture absorption performance and can maintain indoor humidity within a human comfort range for a certain period.

[0051] To further investigate the influence of ambient humidity on the dehumidification performance of the transparent photothermal driven flexible wet pump material, this invention compares its dehumidification effect on different humidity levels within a simulated house by setting different ambient humidity levels. First, the humidity inside the simulated house was set to 50%RH and 70%RH, respectively. Then, a constant temperature and humidity chamber was used to set four external environmental conditions: 30%RH, 50%RH, 70%RH, and 80%RH, simulating dehumidification scenarios under different climatic conditions. Figure 8 shows the changes in internal humidity of the simulated house with different initial internal humidity levels under different external humidity levels. Figure a represents the change in internal humidity of the simulated house with an initial internal humidity of 70%RH, and Figure b represents the change in internal humidity of the simulated house with an initial internal humidity of 50%RH. Throughout the experiment, a high-precision sensor continuously monitored and recorded the changes in temperature and humidity inside and outside the simulated house. Figure 8a shows that, taking an initial indoor humidity of 70%RH as an example, the experimental results show that when the external ambient humidity is 30%RH, the transparent photothermal driven flexible wet pump material exhibits high dehumidification efficiency, reducing the indoor humidity from 70%RH to 36.7%RH within 60 minutes. In a high humidity environment of 80%RH, although the dehumidification speed slows down, the material can still reduce the indoor humidity to 53.88%RH within 60 minutes. This is because in a low humidity environment (30%RH), the larger water vapor partial pressure difference provides a strong driving force for moisture migration, enabling the material to exhibit a faster dehumidification rate. Under high humidity conditions (80%RH), as the water vapor partial pressure difference decreases, the water decomposition and absorption rate decreases, thus slowing down the moisture absorption rate. However, under all four different humidity conditions, the material can effectively regulate indoor humidity in a short time. The trend shown in Figure 8b is the same. The above experimental results demonstrate that the transparent photothermal driven flexible humidity pump material provided by this invention, under photothermal drive, can pump indoor moisture to both medium and high humidity environments, exhibiting good unidirectional continuous dehumidification capability under different humidity conditions. A schematic diagram of continuous dehumidification by the transparent photothermal driven flexible humidity pump material provided by this invention under photothermal drive is shown in Figure 9.

[0052] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A method for preparing a transparent photothermal driven flexible wet pump material, characterized in that, Includes the following steps: Tetraethyl orthosilicate, KH570 silane coupling agent, ethanol, and water are mixed, and the pH of the system is adjusted to 3-4 with acid. After hydrolysis, sol A is obtained. Polymethyl methacrylate microspheres and polyethylene glycol mother liquor are added to sol A, and after mixing evenly, sol B is obtained. Sol B is poured into a mold for gelation, and then lithium chloride solution is added for solvent replacement. Unreacted substances are then removed using acetone to obtain hydrophobic wet gel A. Tetraethyl orthosilicate, KH570 silane coupling agent, ethanol, and water are mixed, and the pH of the system is adjusted to 3-4 with acid. After hydrolysis, sol C is obtained. Polymethyl methacrylate microspheres, polyethylene glycol methacrylate microspheres, TiO2 nanoparticle mother liquor, and polyethylene glycol mother liquor are added to sol C, and after mixing evenly, sol D is obtained. Sol D is poured into a mold for gelation, and then lithium chloride solution is added for solvent replacement. Unreacted substances are then removed using acetone to obtain hydrophilic wet gel B. Tetraethyl orthosilicate, KH570 silane coupling agent, ethanol, and water are mixed, and then lithium chloride solution is added for solvent replacement. Unreacted substances are then removed using acetone to obtain hydrophilic wet gel B. Ethyl acetate, methoxytrimethylsilane, ethanol, and water are mixed, and the pH of the system is adjusted to 2.5–3.0 with acid. After hydrolysis, sol E is obtained. Tungsten oxide photothermal particle dispersion, polyethylene glycol methacrylate microspheres, and KH570 silane coupling agent are added to sol E. After mixing evenly, ammonia is added to adjust the pH of the system to 6.0–6.5 for alkaline catalytic crosslinking to obtain sol F. Sol F is poured into a mold for gelation, and then unreacted substances are removed with anhydrous ethanol. A mixed solution of ethanol and n-hexane is added for solvent replacement to obtain photothermal wet gel C. The hydrophobic wet gel A is laid in a mold, frozen and then the hydrophilic wet gel B is added. After drying, a hydrophilic-hydrophobic bilayer silica aerogel is obtained. The photothermal wet gel C is then coated on the hydrophilic side of the hydrophilic-hydrophobic bilayer silica aerogel. After removing the solvent, a transparent photothermal driven flexible wet pump material composed of a hydrophobic layer, a hydrophilic layer, and a photothermal layer is obtained.

2. The method for preparing the transparent photothermal driven flexible wet pump material according to claim 1, characterized in that, In the preparation steps of the hydrophobic wet gel A, the molar ratio of tetraethyl orthosilicate, KH570 silane coupling agent, ethanol and water is 1:0.3-0.4:10-20:3-5.

3. The method for preparing the transparent photothermal driven flexible wet pump material according to claim 1, characterized in that, In the preparation steps of the hydrophobic wet gel A, the amount of polymethyl methacrylate microspheres added is 3-5% of the mass of sol A; the concentration of the polyethylene glycol mother liquor is 60-70% w / v; and the amount of the polyethylene glycol mother liquor added is 2-3% of the mass of sol A.

4. The method for preparing the transparent photothermal driven flexible wet pump material according to claim 1, characterized in that, In the preparation steps of the hydrophilic wet gel B, the molar ratio of tetraethyl orthosilicate, KH570 silane coupling agent, ethanol and water is 1:0.15~0.25:10~20:3~5.

5. The method for preparing the transparent photothermal driven flexible wet pump material according to claim 1, characterized in that, In the preparation step of the hydrophilic wet gel B, the amount of polymethyl methacrylate microspheres added is 3-5% of the mass of sol C; the amount of polyethylene glycol methacrylate microspheres added is 2-3% of the mass of sol C; the concentration of the polyethylene glycol mother liquor is 60-70% w / v; the amount of the polyethylene glycol mother liquor added is 1-2% of the mass of sol C; the concentration of the TiO2 nanoparticle mother liquor is 10-20 mg / mL; and the amount of the TiO2 nanoparticle mother liquor added is 1-2% of the mass of sol C.

6. The method for preparing the transparent photothermal driven flexible wet pump material according to claim 1, characterized in that, In the preparation steps of the photothermal wet gel C, the molar ratio of tetraethyl orthosilicate, methoxytrimethylsilane, ethanol and water is 1:0.6-0.8:3-5:2-3.

7. The method for preparing the transparent photothermal driven flexible wet pump material according to claim 1, characterized in that, In the preparation steps of the photothermal wet gel C, the concentration of the tungsten oxide photothermal particle dispersion is 10-15 mg / mL; the amount of the tungsten oxide photothermal particle dispersion added is 1.5-3% of the mass of the sol E; the amount of the polyethylene glycol methacrylate microspheres added is 2-3% of the mass of the sol E; and the amount of the KH570 silane coupling agent added is 1-2% of the mass of the sol E.

8. The method for preparing the transparent photothermal driven flexible wet pump material according to claim 1, characterized in that, The thickness ratio of the hydrophobic layer, the hydrophilic layer, and the photothermal layer is 1:3-4:0.4-0.

6.

9. A transparent photothermal driven flexible wet pump material prepared by the preparation method of the transparent photothermal driven flexible wet pump material according to any one of claims 1 to 8.

10. The application of the transparent photothermal driven flexible wet pump material of claim 9 in the preparation of a vortex roller blind.

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