Energy-saving window with functions of heat insulation and active heat energy recovery as well as preparation method and application of energy-saving window

Abstract

The invention relates to the technical field of green buildings, and provides an energy-saving window with heat insulation and active heat energy recovery functions as well as a preparation method and application of the energy-saving window. According to the energy-saving window, a double-glass single-cavity structure with a fluid channel clamped by double-layer glass is adopted, the photo-thermal glass with the photo-thermal conversion film is applied to the outer side, efficient absorption of ultraviolet light and near-infrared light is achieved, visible light penetrates through the photo-thermal glass, indoor natural lighting is not affected, meanwhile, indoor heat gaining is remarkably reduced, the efficient heat insulation target is achieved, and the energy-saving effect is achieved. And the inner side glass is common glass. Meanwhile, fluid such as air and water can be introduced into the cavity between the two layers of glass to achieve heat exchange, heat energy generated by the outer side glass photo-thermal conversion film is recycled in real time, and active collection and utilization of the heat energy are achieved. The energy-saving window provided by the invention is high in climate adaptability, provides an innovative normal form for reducing the comprehensive energy consumption of a building, and has a wide application prospect and remarkable economic benefits and environmental benefits.

Description

Technical Field

[0001] This invention relates to the field of green building technology, and in particular to an energy-saving window that combines heat insulation and active heat recovery functions, as well as its preparation method and application. Background Technology

[0002] Driven by the global energy crisis, energy conservation has become a core direction for the development of green buildings. As a major energy-consuming sector, the building industry accounts for approximately 30% to 40% of global energy consumption, with heating, ventilation, and air conditioning systems accounting for more than half of the total energy demand in buildings. Reducing building energy consumption is of great significance in alleviating energy pressure.

[0003] In building envelopes, windows have the worst thermal insulation performance, and their heat transfer characteristics have a crucial impact on the overall energy efficiency of buildings. Therefore, improving the heat transfer control capabilities of windows has become an important strategy for improving building energy efficiency. From the perspective of solar spectrum characteristics, near-infrared radiation (wavelength range 780~2500 nm) accounts for approximately 50% of total solar energy and is the main source of indoor heat gain. Traditional high-transmittance windows, while ensuring visible light transmission, introduce a large amount of near-infrared radiation, exacerbating indoor heat load and increasing the energy consumption of air conditioning systems.

[0004] To address this issue, new window technologies employ spectrally selective design, limiting near-infrared radiation through high reflectivity or high absorption characteristics without significantly reducing visible light transmittance. Currently, commonly available reflective Low-E glass has a visible light transmittance of approximately 50% and blocks over 90% of near-infrared radiation, reducing indoor heat gain in summer. However, in winter, its reflective properties reflect beneficial near-infrared radiation, reducing solar thermal gain and potentially exacerbating urban light pollution. Absorbent solar thermal glass absorbs near-infrared radiation and converts it into heat, preventing it from entering the room, making it suitable for summer insulation. However, in winter, its solar thermal regulation characteristics hinder the absorption of solar heat indoors, increasing heating energy consumption.

[0005] In summary, existing reflective Low-E glass and absorptive solar thermal glass generally exhibit the characteristic of "energy saving in summer and energy consumption in winter," significantly limiting their climate adaptability. This limitation is even more pronounced in regions with large seasonal temperature differences, making it difficult to achieve stable energy-saving effects throughout the year. Summary of the Invention

[0006] In view of this, the present invention provides an energy-saving window that combines heat insulation and active heat recovery functions, as well as its preparation method and application. The energy-saving window provided by the present invention can efficiently insulate heat while actively collecting and utilizing heat energy, has good climate adaptability, and has significant economic and environmental benefits.

[0007] To achieve the above-mentioned objectives, the present invention provides the following technical solution: An energy-saving window with both heat insulation and active heat recovery functions includes a window frame and double-glazed glass fixed to the window frame; the double-glazed glass includes solar-thermal glass and ordinary glass, and a cavity is formed between the solar-thermal glass and the ordinary glass, the cavity serving as a fluid channel; the window frame is provided with a fluid inlet and a fluid outlet; The photothermal glass includes a glass substrate and a photothermal conversion film disposed on the surface of the glass substrate. The photothermal conversion film is disposed on the side surface of the glass substrate facing the cavity. The photothermal conversion film includes a resin film and near-infrared photothermal nanoparticles and ultraviolet absorbers dispersed in the resin film.

[0008] Preferably, the near-infrared photothermal nanoparticles include Fe3O4@Cu 2-x S, Cs 0.33 The resin film is one or more of WO3@SiO2, indium tin oxide, aluminum-doped zinc oxide, and antimony-doped tin oxide; the resin film is an acrylic resin.

[0009] Preferably, the energy-saving window has an average visible light transmittance of 50%~70%, an ultraviolet light blocking rate of ≥90%, a near-infrared light blocking rate of ≥90%, and a color rendering index Ra≥80.

[0010] This invention also provides a method for preparing an energy-saving window with both heat insulation and active heat recovery functions as described above, comprising the following steps: By assembling solar-thermal glass, ordinary glass, and a window frame, an energy-saving window with both heat insulation and active heat recovery functions is obtained.

[0011] Preferably, the method for preparing the photothermal glass includes the following steps: mixing an ultraviolet absorber, near-infrared photothermal nanoparticles, resin, curing agent and toluene to obtain a slurry; coating the slurry onto the surface of a glass substrate to obtain the photothermal glass.

[0012] Preferably, the mass fraction of near-infrared photothermal nanoparticles in the slurry is 1% to 5%, and the mass fraction of ultraviolet absorber is 1.5% to 2.5%.

[0013] The present invention also provides the application of the energy-saving window with both heat insulation and active heat recovery functions described in the above-described scheme, or the energy-saving window with both heat insulation and active heat recovery functions prepared by the preparation method described in the above-described scheme, in building structures.

[0014] Preferably, the building structure includes skylights, curtain wall systems, or building facade windows.

[0015] Preferably, in the application, fluid is introduced into the fluid channel of the energy-saving window; the fluid includes one or more of air, water, and photothermal nanofluids.

[0016] Preferably, the energy-saving window is integrated with an intelligent control system, which dynamically adjusts the flow rate of the fluid based on weather parameters.

[0017] This invention provides an energy-saving window with both heat insulation and active heat recovery functions, comprising a window frame and double-glazed glass fixed to the window frame; the double-glazed glass comprises photothermal glass and ordinary glass, with a cavity formed between the photothermal glass and ordinary glass, the cavity serving as a fluid channel; the window frame is provided with a fluid inlet and a fluid outlet; the photothermal glass comprises a glass substrate and a photothermal conversion film disposed on the surface of the glass substrate, the photothermal conversion film being disposed on the side of the glass substrate facing the cavity; the photothermal conversion film comprises a resin film and near-infrared photothermal nanoparticles and an ultraviolet absorber dispersed in the resin film. The energy-saving window provided by this invention integrates a spectrally selective photothermal conversion film and a fluid-assisted heat collection system, employing a double-glass single-cavity architecture with a fluid channel sandwiched between the double-glazed glass. Photothermal glass with a photothermal conversion film is applied to the outer side, achieving efficient absorption of ultraviolet and near-infrared light while allowing visible light to pass through, significantly reducing indoor heat gain without affecting natural indoor lighting, achieving the goal of efficient heat insulation; the inner glass is ordinary glass. Simultaneously, the fluid channel between the double-glazed windows allows for the exchange of heat through air, water, and other fluids, enabling real-time recovery of heat energy generated by the photothermal conversion film on the outer glass, thus achieving active heat collection and utilization. This structure overcomes the technical shortcomings of traditional reflective Low-E glass and absorptive photothermal glass, namely "one-way insulation" and "winter heat loss," and can be applied to hot climate zones and climate zones with significant seasonal variations such as hot summers and cold winters. In summer, it can block more than 95% of near-infrared radiation, significantly reducing the interior temperature of the building, while the collected heat energy can be used to heat domestic water or drive thermal response equipment; in winter, the collected heat energy can be directly used to preheat the ventilation air entering the room, reducing the building's internal heating energy consumption. Furthermore, the energy-saving window of this invention can be integrated with an intelligent control system to dynamically adjust the fluid flow rate based on weather parameters, achieving a balance between the fluid inlet and outlet temperatures and heat collection efficiency, thereby maximizing heat collection efficiency. In summary, this invention provides an innovative paradigm for reducing the overall energy consumption of buildings, with broad application prospects and significant economic and environmental benefits. Attached Figure Description

[0018] Figure 1 A schematic diagram of the structure of the energy-saving window that combines heat insulation and active heat recovery functions provided by the present invention; Figure 2 Transmittance curves for energy-saving windows, ordinary windows, and Low-E windows; Figure 3 Reflectance curves for energy-saving windows, ordinary windows, and Low-E windows; Figure 4Absorption rate curves for energy-saving windows, ordinary windows, and Low-E windows; Figure 5 Color rendering performance for energy-efficient windows, standard windows, and Low-E windows; Figure 6 This is a schematic diagram of the hot chamber structure; Figure 7 Temperature profile of the hot chamber for outdoor hot chamber testing; Figure 8 The fluid inlet and outlet temperature profiles of the Air-SPW during outdoor hot chamber testing; Figure 9 The inlet and outlet temperature differences of the Air-SPW at different time periods during outdoor hot chamber testing; Figure 10 Optical testing of the aging performance of CWO films with and without SiO2 coating. Detailed Implementation

[0019] This invention provides an energy-saving window that combines heat insulation and active heat recovery functions, including a window frame and double-glazed glass fixed to the window frame; the double-glazed glass includes solar-thermal glass and ordinary glass, and a cavity is formed between the solar-thermal glass and the ordinary glass, the cavity serving as a fluid channel; the window frame is provided with a fluid inlet and a fluid outlet; The photothermal glass includes a glass substrate and a photothermal conversion film disposed on the surface of the glass substrate. The photothermal conversion film is disposed on the side surface of the glass substrate facing the cavity. The photothermal conversion film includes a resin film and near-infrared photothermal nanoparticles and ultraviolet absorbers dispersed in the resin film.

[0020] The present invention does not have any special requirements for the ordinary glass; any glass known to those skilled in the art can be used.

[0021] In this invention, the glass substrate in the photothermal glass is preferably ordinary glass. This invention does not have special requirements for the ordinary glass; any glass well-known to those skilled in the art can be used, such as silicate glass. The side of the photothermal glass facing the cavity is referred to as the inner side. The photothermal conversion film includes a resin film and near-infrared photothermal nanoparticles and an ultraviolet absorber dispersed in the resin film. The near-infrared photothermal nanoparticles preferably include Fe3O4@Cu. 2-x S, Cs 0.33 One or more of WO3@SiO2, indium tin oxide, aluminum-doped zinc oxide, and antimony-doped tin oxide, more preferably Cs 0.33 WO3@SiO2 (CWO@SiO2, Cs coated with silica) 0.33 WO3 particles); in this field, Cs 0.33WO3 (CWO) is susceptible to aging and failure due to environmental corrosion in practical applications. This invention uses SiO2-coated modified CWO. The SiO2 coating layer constructs a stable physical and chemical protective barrier on the surface of CWO particles, which can effectively isolate external water vapor, oxygen and chemical substances from the corrosion of CWO, thereby effectively solving the problem of CWO aging and failure, and greatly improving the stability and reliability of photothermal conversion film and energy-saving window system during long-term use.

[0022] In this invention, the preferred method for preparing CWO@SiO2 includes the following steps: mixing CWO powder, a surfactant, and an alcohol solvent, followed by ultrasonic dispersion to obtain a dispersion; mixing the dispersion with a silicon source to obtain a mixed solution; adding ammonia and deionized water to the mixed solution to react and obtain CWO@SiO2 composite particles; in this invention, the surfactant is preferably hexadecyltrimethylammonium bromide (CTAB); the mass ratio of CWO powder to surfactant is preferably 1:1 to 1.5, specifically 1:1; the alcohol solvent is preferably anhydrous ethanol; the ratio of CWO powder to alcohol solvent is preferably 1g:200 to 400mL, specifically 1g:300mL; the preferred ultrasonic dispersion time is... The reaction time is 30-60 min; the silicon source is preferably tetraethyl orthosilicate, and the ratio of CWO powder to silicon source is preferably 0.2 g: 0.5-1 mL, more preferably 0.2 g: 0.5 mL; the concentration of ammonia is preferably 30 wt%; the ratio of CWO powder, ammonia, and deionized water is preferably 0.2 g: 0.2-0.5 mL: 0.1-0.2 mL, specifically 0.2 g: 0.2 mL: 0.16 mL; the reaction temperature is preferably 40-70℃, specifically 50℃, and the reaction time is preferably 6-10 h, specifically 8 h; after the reaction is completed, the resulting reaction solution is preferably centrifuged, the precipitate is collected, washed, dried, ground, and sieved to obtain the CWO@SiO2 composite particles.

[0023] In this invention, the resin film is preferably an acrylic resin; the invention does not have special requirements for the ultraviolet absorber, and commercially available products well known to those skilled in the art can be used. In a specific embodiment of this invention, the ultraviolet absorber can be Chiguard. ®5582; The preferred mass ratio of the near-infrared photothermal nanoparticles to the ultraviolet absorber is 1-5:2. This invention employs an ultraviolet absorber and photothermal nanomaterials to selectively absorb ultraviolet light (280-380 nm) and near-infrared light (780-2500 nm), converting it into heat energy. By changing the mass fraction of the photothermal material, the visible light transmittance can be adjusted. Simultaneously, the photothermal nanomaterials have a wide band gap, exhibiting no intrinsic absorption in the visible light range (380-780 nm). They convert near-infrared light into heat energy through two mechanisms: local surface plasmon resonance and small polaron absorption, thus possessing high visible light transmittance. In summary, the energy-saving window provided by this invention exhibits extremely high absorption rates in the ultraviolet (280-380 nm) and near-infrared (780-2500 nm) bands, while possessing high transmittance in the visible light band (380-780 nm).

[0024] In this invention, the photothermal glass has high transmittance in the visible light band, a color rendering index Ra value greater than 80, and high rendering accuracy for common colors, which can meet the color requirements of buildings.

[0025] This invention does not have special requirements for the thickness of the photothermal glass, ordinary glass, and fluid channel; customization can be made according to actual needs. In a specific embodiment of this invention, the thickness of the glass substrate in the photothermal glass is preferably 6 mm, the thickness of the photothermal conversion film is preferably 5-20 micrometers, and can specifically be 10 micrometers; the thickness of the ordinary glass is preferably 6 mm, and the thickness of the fluid channel is preferably 12 mm.

[0026] The present invention does not have any special requirements for the window frame, and any frame known to those skilled in the art can be used; in a specific embodiment of the present invention, the fluid inlet is located at the bottom of the window frame, and the fluid outlet is located at the top of the window frame. Fluid is introduced into the fluid channel, and the heat energy generated is collected and utilized by the heat exchange between the fluid and the photothermal conversion film.

[0027] In this invention, the energy-saving window has an average visible light transmittance of 50%~70%, an ultraviolet light blocking rate of ≥90%, a near-infrared light blocking rate of ≥90%, and a color rendering index Ra≥80.

[0028] This invention also provides a method for preparing an energy-saving window with both heat insulation and active heat recovery functions as described above, comprising the following steps: By assembling solar-thermal glass, ordinary glass, and a window frame, an energy-saving window with both heat insulation and active heat recovery functions is obtained.

[0029] In this invention, the preparation method of the photothermal glass includes the following steps: mixing an ultraviolet absorber, near-infrared photothermal nanoparticles, resin, curing agent, and toluene to obtain a slurry; coating the slurry onto the surface of a glass substrate to obtain the photothermal glass. In a specific embodiment of this invention, the resin is preferably an acrylic resin, specifically JZ-9522 acrylic resin, and the curing agent is preferably N3390; the mass ratio of toluene to resin is preferably 1:2; the near-infrared photothermal nanoparticles are preferably used in the form of a near-infrared photothermal nanoparticle dispersion, and the solvent of the near-infrared photothermal nanoparticle dispersion is preferably toluene; the concentration of the near-infrared photothermal nanoparticle dispersion is preferably 25%.

[0030] In this invention, the mass fraction of near-infrared photothermal nanoparticles in the slurry is preferably 1% to 5%, specifically 1%, 2%, 3% or 5%, and the mass fraction of ultraviolet absorber is preferably 1.5% to 2.5%, specifically 2%. The coating method is preferably bar coating. This invention does not have special requirements for the specific operation method of bar coating, and any method known to those skilled in the art can be used.

[0031] This invention also provides the application of the energy-saving window with both heat insulation and active heat recovery functions described in the above-described scheme, or the energy-saving window with both heat insulation and active heat recovery functions prepared by the preparation method described in the above-described scheme, in a building structure; the building structure includes skylights, curtain wall systems, or building facade windows. In this invention, the ordinary glass side of the energy-saving window faces the interior during the application.

[0032] In this invention, during application, fluid is introduced into the cavity of the energy-saving window. The fluid flows in from the fluid inlet and flows out from the fluid outlet. The fluid preferably includes one or more of air, water, and photothermal nanofluids. Specifically, the photothermal nanofluid can be a fluid containing photothermal nanoparticles. The fluid containing photothermal nanoparticles preferably includes a solvent and photothermal nanoparticles dispersed in the solvent. The photothermal nanoparticles are preferably one or more of Au nanoparticles, Al2O3 nanoparticles, and ATO nanoparticles. The solvent is preferably water.

[0033] In this invention, the energy-saving window is preferably integrated with an intelligent control system, which dynamically adjusts the flow rate of the fluid according to weather parameters. The intelligent control system includes an environmental sensor and an edge computing unit. The environmental sensor preferably includes one or more of a temperature and humidity sensor, a solar irradiance sensor, and a wind speed feedback module. The edge computing unit analyzes outdoor meteorological parameters (such as irradiance and indoor-outdoor temperature difference) in real time based on data from the environmental sensor, and dynamically adjusts the fluid velocity in the fluid channel. Under strong irradiance conditions, the flow rate is increased to enhance heat recovery efficiency, while the flow rate is reduced in cloudy or rainy weather, achieving an optimal balance between heat collection efficiency and system energy consumption.

[0034] In the solar spectrum, near-infrared radiation (780~2500nm) accounts for approximately 50% of total solar radiation and is the primary source of indoor heat gain. Solar thermal glass converts over 90% of the near-infrared spectral energy into heat, preventing it from entering the building through transmission. Meanwhile, the fluid within the fluid channels carries away the heat generated by the solar thermal glass through heat exchange, reducing the heat gain entering the building through radiation and heat conduction. In hot seasons, the insulation function, as a core attribute, effectively blocks external heat from entering the building, significantly reducing cooling energy consumption. Simultaneously, the heat generated by the solar thermal glass can be collected and used to heat domestic water or drive heating equipment. In cold seasons, the heat generated by the solar thermal glass can directly preheat the incoming fresh air, reducing the energy consumption of the heating system, thus achieving efficient operation throughout the year and avoiding the heat loss problems associated with Low-E glass in winter.

[0035] The technical solutions of this invention will be clearly and completely described below with reference to the embodiments thereof. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0036] In the following embodiments, Cs is used 0.33 The preparation method of WO3@SiO2 is as follows: (1) Weigh 0.2 g CWO powder and 0.2 g cetyltrimethylammonium bromide (CTAB), add them to 60 mL of anhydrous ethanol, and stir magnetically at room temperature for 20 min until they are evenly mixed.

[0037] (2) Transfer the above mixture into an ultrasonic disperser and ultrasonically disperse for 30 min.

[0038] (3) Place the ultrasonically mixed solution in a 50°C constant temperature water bath, add 0.5 mL of tetraethyl orthosilicate (TEOS), and continue to stir magnetically for 5 min.

[0039] (4) While stirring continuously, slowly add 0.2 mL of ammonia water (concentration of 30wt%) and 0.16 mL of deionized water in sequence, and keep the reaction at a constant temperature of 50℃ in a water bath for 8 h.

[0040] (5) After the reaction is complete, the mixture is centrifuged at 7000 rpm for 10 min, the precipitate is collected, washed with anhydrous ethanol, and the centrifugation-washing operation is repeated 3 times.

[0041] (6) Place the washed CWO@SiO2 precursor into an oven and dry it at 50 °C until constant weight.

[0042] (7) Grind the dried product and sieve it through a standard sieve to obtain CWO@SiO2 composite particles.

[0043] Example 1 (1) Add 0.4g of the ultraviolet absorber Chiguard ® 5582, 3g Cs with a mass fraction of 25% 0.33 WO3@SiO2 (CWO@SiO2) toluene dispersion, 5g toluene and 1.5g curing agent N3390 were added to 10g JZ-9522 acrylic resin and mixed evenly. Photothermal conversion film was prepared on one side of ordinary glass with a thickness of 6mm by wire rod coating process to obtain photothermal glass, wherein the thickness of the photothermal conversion film is about 10μm.

[0044] (2) According to Figure 1 The structure shown is obtained by assembling the solar thermal glass prepared in step (1), ordinary glass with a thickness of 6mm, and the window frame to obtain an energy-saving window. A cavity is formed between the solar thermal glass and the ordinary glass, and the cavity has a thickness of 12mm. The bottom and top of the window frame are reserved with fluid inlet and fluid outlet respectively.

[0045] The energy-saving window (Air-SPW) prepared in step (2) was compared with ordinary windows (CW) and Low-E windows (LW). The ordinary window was assembled with two pieces of ordinary glass with a thickness of 6 mm and a window frame. There were no fluid inlets or outlets on the window frame, and the cavity in the middle formed a vacuum cavity. The Low-E window was assembled with Low-E glass with a thickness of 6 mm, ordinary glass with a thickness of 6 mm and a window frame. There were no fluid inlets or outlets on the window frame, and the cavity in the middle formed a vacuum cavity. The structures of the three types of windows are shown in Table 1.

[0046] Table 1. Structural Analysis and Advantages / Disadvantages of Energy-Saving Windows (Air-SPW), Standard Windows (CW), and Low-E Windows (LW)

[0047] The optical performance of energy-saving windows, ordinary windows, and Low-E windows was tested, and the results are as follows: Figures 2-5As shown, Figures 2-5 The figures show the transmittance curves, reflectance curves, absorptivity curves, and color rendering performance of three types of windows.

[0048] Figures 2-5 The results show that in the visible light range (400~780 nm), the transmittance of Air-SPW is 64.47%, significantly higher than that of LW (50.23%); in the near-infrared range (780~2500 nm), the light blocking rate of Air-SPW is 95.25%, roughly equivalent to that of LW (98.27%). Furthermore, as an absorptive glass, Air-SPW differs from reflective Low-E glass by primarily controlling solar radiation through absorption, fundamentally and effectively avoiding the urban light pollution problems caused by specular reflection in Low-E glass, ensuring functional performance while demonstrating excellent environmental friendliness. Notably, Air-SPW has a color rendering index (Ra) of 93.1, accurately reproducing the true colors of objects while simultaneously achieving excellent thermal insulation and heat harvesting capabilities. This comprehensive advantage makes it a highly competitive alternative to ordinary windows (CW) and Low-E windows (LW), demonstrating unique value, especially in scenarios where architectural aesthetics, functional requirements, and ecological benefits must be balanced.

[0049] Outdoor thermal chamber tests were conducted on energy-saving windows, ordinary windows, and Low-E windows. During the test, air was introduced into the fluid channel of the energy-saving window at a flow rate of 0.1 m / s. Figure 6 As shown, the hot chamber is surrounded by 20mm thick polystyrene foam board, and the outer surface is covered with 1mm thick aluminum foil tape to ensure airtightness and reflect solar radiation, ensuring that the heat inside the hot chamber mainly comes from the window. The outer dimensions of the hot chamber are 30cm×30cm×30cm, with a 14cm×24cm opening on one side for installing the window model. T-type thermocouples are used to monitor the air temperature (④) inside the hot chamber, the temperature at the center point of the inner glass surface of the window (③), the temperature at the center point of the outer glass surface of the window (②), and the outdoor ambient temperature (①). A JK808 handheld multi-channel thermometer (Jinke) is used to collect temperature data.

[0050] The internal temperature curve of the hot chamber in the outdoor hot chamber test is as follows: Figure 7 As shown, the fluid inlet and outlet temperature curves of Air-SPW are as follows: Figure 8 As shown, the inlet and outlet temperature differences of Air-SPW at different time periods are as follows: Figure 9 As shown. According to Figure 7 It can be seen that during periods of strong solar irradiation (10:00~14:00), the hot chamber temperature of the Air-SPW is about 3~4℃ lower than that of the CW, demonstrating excellent passive cooling performance. Particularly between 12:00 and 14:00, the average inlet and outlet temperature difference of the Air-SPW reaches 5.4℃. Figure 9 This fully validated the system's heat collection capabilities. By optimizing parameters such as window size design, airflow path layout, and airflow velocity, the heat collection efficiency of Air-SPW can be further improved, enhancing its building energy efficiency and indoor thermal comfort control performance.

[0051] Following the method in step (1) of Example 1, Cs was replaced with CWO without SiO2 coating. 0.33 Photothermal conversion films were prepared using WO3@SiO2, and the aging performance of CWO films with and without SiO2 coating was optically tested. The results are as follows: Figure 10 As shown. Figure 10 The results show that using Cs 0.33 The transmittance curves of the photothermal conversion film prepared by WO3@SiO2 at 0h, 60h, 90h, and 240h almost completely overlap, indicating that the SiO2 coating layer effectively inhibits the aging of CWO particles, and the transmittance and photothermal conversion capability of the film remain stable during long-term testing. However, the transmittance curve of the photothermal conversion film prepared using uncoated SiO2 CWO shows a significant shift with increasing testing time, with a marked decrease in transmittance in the visible light region and a gradual weakening of absorption intensity in the near-infrared region. Furthermore, the longer the testing time, the greater the attenuation, indicating that uncoated SiO2 CWO particles are prone to aging and failure in the environment, leading to deterioration of the film's optical properties.

[0052] The results of the above embodiments demonstrate that the energy-saving window provided by the present invention has the following advantages: Achieving a balance between natural lighting (visible light transmittance) and near-infrared blocking rate: High near-infrared blocking rate is often accompanied by relatively low visible light transmittance. For example, when the near-infrared blocking rate of a triple-silver Low-E double-glazed window is 98.27%, the visible light transmittance is only 50.23%. The energy-saving window provided by this invention achieves a near-infrared blocking rate of 95.25% while maintaining a visible light transmittance of 64.47%, and this optical performance can be adjusted by changing the content of photothermal nanoparticles.

[0053] Achieving synergistic optimization of building "light-heat-fluid": Selectively converting solar spectrum through photothermal conversion film to convert light energy into heat energy, and collecting and utilizing heat energy through heat exchange in fluid channels, thereby improving the comprehensive utilization rate of solar energy.

[0054] Seasonal adaptability: Low-E insulated glass and traditional absorptive insulated glass are only beneficial for heat insulation in hot seasons, but they prevent heat from entering the room during cold seasons, exhibiting significant limitations in seasonal adaptability. The energy-saving window of this invention effectively solves this problem, capable of adaptive adjustment according to the climatic characteristics of different seasons. In summer, the high near-infrared blocking rate of the photothermal conversion film effectively blocks heat from solar radiation, reducing the load on indoor air conditioning. In winter, although it still absorbs solar radiation, the absorbed heat can be used to preheat the incoming fresh air through airflow, increasing indoor temperature and reducing heating energy consumption. Furthermore, by optimizing airflow velocity, the overall efficiency of solar energy utilization can be further improved. For example, under sufficient sunlight, appropriately increasing the airflow velocity accelerates heat transfer; under weak sunlight, decreasing the airflow velocity reduces energy loss.

[0055] Overcoming the limitations of traditional windows that only insulate but do not generate heat, the energy-saving window provided by this invention has the dual functions of heat insulation and active heat recovery, greatly improving the utilization rate of the solar spectrum. Previously wasted solar energy is effectively converted into usable heat energy, reducing the building's dependence on traditional energy sources. Simultaneously, by reducing the operating time and energy consumption of air conditioning and heating equipment, the overall energy consumption of the building is significantly reduced. This not only lowers the building's operating costs but also reduces its environmental impact, making a significant contribution to achieving energy conservation and emission reduction goals in buildings.

[0056] The innovative energy-saving window constructed by this invention has significant advantages in balancing natural lighting and near-infrared blocking, optimizing the synergistic effect of building "light-heat-fluid", seasonal adaptability, breaking through traditional limitations, and economic universality. It provides new ideas and methods for building energy conservation and solar energy utilization, and is expected to be widely used in the future building field.

[0057] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. An energy-saving window that combines heat insulation and active heat recovery functions, characterized in that, The device includes a window frame and double-glazed glass fixed to the window frame; the double-glazed glass includes photothermal glass and ordinary glass, and a cavity is formed between the photothermal glass and the ordinary glass, the cavity serving as a fluid channel; the window frame is provided with a fluid inlet and a fluid outlet; The photothermal glass includes a glass substrate and a photothermal conversion film disposed on the surface of the glass substrate. The photothermal conversion film is disposed on the side surface of the glass substrate facing the cavity. The photothermal conversion film includes a resin film and near-infrared photothermal nanoparticles and ultraviolet absorbers dispersed in the resin film.

2. The energy-saving window according to claim 1, characterized in that, The near-infrared photothermal nanoparticles include Fe3O4@Cu 2-x S, Cs 0.33 The resin film is one or more of WO3@SiO2, indium tin oxide, aluminum-doped zinc oxide, and antimony-doped tin oxide; the resin film is an acrylic resin.

3. The energy-saving window according to claim 1, characterized in that, The energy-saving window has an average visible light transmittance of 50%~70%, an ultraviolet light blocking rate of ≥90%, a near-infrared light blocking rate of ≥90%, and a color rendering index Ra≥80.

4. The method for preparing the energy-saving window with both heat insulation and active heat recovery functions as described in any one of claims 1 to 3, characterized in that, Includes the following steps: By assembling solar-thermal glass, ordinary glass, and a window frame, an energy-saving window with both heat insulation and active heat recovery functions is obtained.

5. The preparation method according to claim 4, characterized in that, The method for preparing the photothermal glass includes the following steps: mixing an ultraviolet absorber, near-infrared photothermal nanoparticles, resin, curing agent and toluene to obtain a slurry; coating the slurry onto the surface of a glass substrate to obtain the photothermal glass.

6. The preparation method according to claim 5, characterized in that, The slurry contains 1% to 5% by mass of near-infrared photothermal nanoparticles and 1.5% to 2.5% by mass of ultraviolet absorber.

7. The application of the energy-saving window with both heat insulation and active heat recovery functions as described in any one of claims 1 to 3, or the energy-saving window with both heat insulation and active heat recovery functions prepared by the preparation method described in any one of claims 4 to 6, in building structures.

8. The application according to claim 7, characterized in that, The building structure includes skylights, curtain wall systems, or building facade windows.

9. The application according to claim 7 or 8, characterized in that, In the application, fluid is introduced into the fluid channel of the energy-saving window; the fluid includes one or more of air, water, and photothermal nanofluids.

10. The application according to claim 9, characterized in that, The energy-saving window is integrated with an intelligent control system, which dynamically adjusts the flow rate of the fluid based on weather parameters.

Images