Self-generating device based on radiation refrigeration and photo-thermal material

Abstract

The utility model belongs to the technical field of new energy and energy conservation, and relates to a self-generating device based on radiation refrigeration and photo-thermal materials, which comprises a greenhouse, a photo-thermal thin film layer, a radiation cooling thin film layer and a thermoelectric conversion component, and the thermoelectric conversion component sequentially comprises an upper heat conduction layer, a thermoelectric device and a lower heat conduction layer from top to bottom. The thermoelectric device comprises at least one thermoelectric unit, and each thermoelectric unit comprises a thermoelectric gel electrolyte and electrodes arranged on the two sides of the thermoelectric gel electrolyte. The radiation cooling film is used as the cold end of the thermoelectric conversion assembly, and the photo-thermal material is used as the hot end, so that the generated temperature difference is converted into electromotive force through the thermoelectric gel electrolyte, and then electric energy is generated; the whole thermoelectric power generation device is simple in structure, low in cost and good in cyclic utilization effect, achieves daytime heat collection and all-weather refrigeration, improves the energy utilization efficiency, and can be used as a green and sustainable power supply for supplying power to electronic products.

Description

Technical Field

[0001] This utility model belongs to the field of new energy and energy conservation technology, and relates to the comprehensive utilization of thermal energy and electrical energy, and in particular to a self-generating device based on radiative cooling and photothermal materials. Background Technology

[0002] With fossil fuels becoming increasingly scarce, solar energy has become an important component of human energy use. As a clean and renewable energy source, solar energy is both a primary energy source and a renewable energy source, making it an ideal alternative to fossil fuels and it has been widely applied in various fields. Solar thermoelectric conversion technology, as an emerging green and environmentally friendly power generation method, has the characteristics of simple structure, no noise, and no pollution, and has broad development prospects. However, its disadvantages are instability and the need for sunlight to operate normally; otherwise, it will affect the quality of electricity.

[0003] Radiative cooling is a completely energy-free and greenhouse gas-free passive cooling technology. It utilizes materials to spontaneously dissipate their own heat through atmospheric transparent windows with wavelengths of 8-13 μm into the cold outer space, and reflect sunlight with wavelengths of approximately 0.3-2.5 μm back, thereby achieving spontaneous cooling of building surfaces or other equipment surfaces. This technology holds the promise of replacing air-compression-based cooling systems and will have a significant impact on the global energy landscape and global climate change.

[0004] Combining radiative cooling power generation with solar power generation could generate additional electricity while cooling solar power equipment, providing all-weather power for micro and small devices such as automatic radio receivers, automatic weather forecasting stations, microwave relay stations, and unmanned navigation lights. However, the power generation efficiency of current thermoelectric power generation devices still has room for improvement. Utility Model Content

[0005] The purpose of this invention is to overcome the shortcomings of existing radiative cooling devices and solar thermoelectric power generation systems, and to provide a highly efficient integrated system capable of all-weather thermoelectric conversion. It uses a photothermal film as the hot end of the thermoelectric device to improve the utilization rate of solar energy; it uses a radiative cooling film with high cooling efficiency as the cold end, which has a simple structure and good recycling effect; and the thermoelectric gel with a high Seebeck coefficient has good thermoelectric conversion efficiency.

[0006] The technical solution adopted by this utility model to achieve the above objectives is as follows:

[0007] A self-generating power device based on radiative cooling and photothermal materials includes a photothermal thin film layer, a radiative cooling thin film layer, and a thermoelectric conversion component. The thermoelectric conversion component, from top to bottom, includes an upper thermally conductive layer, a thermoelectric device, and a lower thermally conductive layer. The thermoelectric device includes at least one thermoelectric unit, which comprises a thermoelectric gel electrolyte and electrodes disposed on both sides of the thermoelectric gel electrolyte. The upper thermally conductive layer is adjacent to the photothermal thin film layer, and the lower thermally conductive layer is adjacent to the radiative cooling thin film layer. This invention, by employing the aforementioned technical solution, uses the photothermal thin film as the hot end of the thermoelectric conversion component and the radiative cooling thin film as the cold end, creating a temperature difference between the two ends of the thermoelectric conversion component. This temperature difference is converted into electromotive force by the thermoelectric unit in the thermoelectric conversion component, thereby generating electrical energy. The entire thermoelectric power generation device has a simple structure, low cost, and good recycling effect. It can achieve daytime heat collection and all-weather cooling, improving energy utilization efficiency and serving as a green and sustainable power source for electronic products.

[0008] Preferably, the radiation cooling film of the radiation cooling film layer is a composite film with a reflectivity of not less than 90% in the solar spectrum and an infrared emissivity of not less than 90% in the atmospheric window. More preferably, the radiation cooling film is composed of organic polymers and inorganic micro / nano particles, and is bonded to one end of the thermoelectric conversion component with thermally conductive silicone grease, adhering to the surface of the lower thermally conductive layer of the thermoelectric conversion component as a cold end. Even more preferably, the thickness of the radiation cooling film layer is 120-170 μm.

[0009] Preferably, the organic polymer contains functional groups / bonds such as CO, CN, and CY (where Y represents a halogen element, such as F, Cl, and Br), and exhibits strong absorption due to bending vibrations in the 7-16 μm range, making it an ideal material for radiation cooling. More preferably, it is selected from at least one of polyvinylidene fluoride, poly(vinylidene fluoride-co-hexafluoropropylene), polyethylene oxide, polylactic acid, and polytetrafluoroethylene. The inorganic micro / nanoparticles with a diameter of 10 nm to 100 nm have low solar absorptivity and high solar reflectivity (wide bandgap), and more preferably, they are selected from at least one of silicon dioxide, titanium dioxide, alumina, barium sulfate, and calcium carbonate.

[0010] Preferably, the upper and lower thermally conductive layers are thermal greases. More preferably, the thermal grease is selected from commercially available thermal greases, and even more preferably, Thermalright TF8 thermal grease with a thermal conductivity of 13.8 W / (m*K).

[0011] Preferably, the absorbance of the photothermal film layer under the solar absorption spectrum is not less than 90%; more preferably, the preferred layer thickness of the photothermal film layer is 10-30 μm; even more preferably, the photothermal material of the photothermal film layer is selected from at least one of multi-walled carbon nanotubes, monolayer MXene, graphene, carbon black, copper-zinc particles, carbon fibers, and carbonized lignin nanoparticles.

[0012] Preferably, the thermoelectric gel electrolyte comprises a redox pair with a high Seebeck coefficient, a water-soluble polymer, and a conductive polymer, wherein the mass ratio of the redox pair to the water-soluble polymer to the conductive polymer is (5-20):(10-40):(1-10). By using the conductive polymer as the conductive matrix and introducing the redox pair with a high Seebeck coefficient, good thermoelectric performance is provided. The addition of the water-soluble polymer forms a cross-linked conductive network structure, which can maintain a certain shape and possesses high flexibility, biocompatibility, and excellent mechanical properties. More preferably, the high Seebeck coefficient of the redox pair is not less than 0.6 mVK. -1 .

[0013] Preferably, the conductive polymer of the thermogel electrolyte is selected from at least one of polythiophene, polyaniline, polypyrrole, polyacetylene, and polystyrene; the water-soluble polymer is selected from at least one of polyvinyl alcohol and polyacrylamide; and the redox couple is selected from SO4. 2- and SO3 2- [Fe(CN)6] 3- and [Fe(CN)6] 4- I - and I3 - Fe 2+ and Fe 3+ At least one of them.

[0014] Preferably, the electrode comprises a copper sheet.

[0015] Preferably, a greenhouse is disposed above the photothermal film layer. The greenhouse consists of a chamber formed by the photothermal film layer and plexiglass, and a greenhouse material filled into the chamber. More preferably, the greenhouse material includes at least one greenhouse gas and a phase change thermal storage material; even more preferably, the greenhouse gas or phase change thermal storage material includes at least one of carbon dioxide, water vapor, methane, carbon monoxide, ozone, and liquid paraffin. By adding a plexiglass shell to the hot-end photothermal film layer to form a greenhouse, the temperature at the hot end increases, further improving power generation efficiency.

[0016] Preferably, the self-generating device further includes a heat-insulating support frame.

[0017] Preferably, the surface of the heat-insulating bracket is provided with a heat-insulating layer to block heat exchange between the heat-insulating bracket and the thermoelectric conversion component. More preferably, the heat-insulating layer includes at least one of glass fiber, polyurethane, polystyrene, and aluminum silicate.

[0018] Preferably, the self-generating device based on radiative cooling and photothermal materials of this utility model includes: a radiative cooling thin film layer, a photothermal thin film layer, and a thermoelectric conversion component. The thermoelectric conversion component includes an upper heat-conducting layer, a thermoelectric device, and a lower heat-conducting layer arranged sequentially from top to bottom. The thermoelectric device is composed of one or more thermoelectric units arranged in parallel or in series. The non-connected electrode conductor is in contact with the upper heat-conducting layer, and the connected electrode conductor is in contact with the lower heat-conducting layer. The thermoelectric unit includes a thermoelectric gel electrolyte and electrodes disposed on both sides of the thermoelectric gel electrolyte. The upper heat-conducting layer is in contact with the photothermal thin film layer, and the lower heat-conducting layer is in contact with the radiative cooling thin film layer. The self-generating device also includes a greenhouse disposed above the photothermal thin film layer and a heat-insulating support that runs through the thermoelectric conversion component.

[0019] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0020] 1) This utility model is a novel power generation method that utilizes solar photovoltaic renewable energy and atmospheric ambient temperature to generate electricity. It requires no electricity or other traditional energy sources, and is clean and energy-free. At the same time, this device can create a large temperature difference between the two ends of the thermoelectric conversion component, generating a large electromotive force.

[0021] 2) The use of a dual-effect system of solar thermal material for heat collection and radiation cooling can realize heat collection during the day and cooling in all weather, enabling the device to be used in multiple ways, in all weather and across seasons, and improving the overall efficiency of energy utilization.

[0022] 3) It uses radiation cooling material as the cold end, which also has a cooling function, making it more versatile.

[0023] 4) Thermoelectric gel electrolyte thermoelectric devices replace the thermoelectric metal sheets in traditional thermoelectric power generation devices, making them applicable to a wider range of scenarios.

[0024] 5) The device is simple, low-cost, and highly efficient, solving the shortcomings of solar absorption cooling, such as inability to operate at night, low efficiency of radiation cooling during daytime operation, and high cold source temperature, and has a broader market application prospect. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the self-generating device of the present invention; in the figure, 1-photothermal thin film layer, 2-radiative cooling thin film layer, 3-thermoelectric device, 4-upper heat-conducting layer, 5-lower heat-conducting layer, 6-greenhouse, 7-heat insulation bracket, 8-voltage amplifier, 9-load.

[0026] Figure 2This is a schematic diagram of a thermoelectric device unit. Detailed Implementation

[0027] To better clarify and understand the purpose, process, and advantages of this utility model, the technical solution and implementation methods of this utility model will be further described clearly, completely, and in detail below through specific embodiments and in conjunction with the accompanying drawings. It should be understood that the embodiments described in this utility model are implemented under the premise of the technical solution of this utility model, providing detailed implementation methods and specific operating procedures, but are only some embodiments of this utility model, not all embodiments. The specific implementation methods described are limited to illustrating and explaining this utility model and do not limit this utility model. Based on the embodiments of this utility model, all other implementation methods obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0028] Unless otherwise specified, the experimental methods and conditions used in the following embodiments are conventional methods and conditions. The materials, reagents, and instruments used in the embodiments, unless otherwise specified, can be obtained commercially or prepared by conventional methods. The reaction conditions described in this utility model can achieve the stated reaction and obtain the desired product. Due to space limitations, some embodiments are listed below to further illustrate the advantages of the technical solution of this utility model.

[0029] like Figure 1 As shown, one embodiment of this utility model provides a self-generating device based on radiative cooling and photothermal materials, including a photothermal thin film layer 1, a radiative cooling thin film layer 2, and a thermoelectric conversion component. The thermoelectric conversion component, from top to bottom, includes an upper heat-conducting layer 4, a thermoelectric device 3, and a lower heat-conducting layer 5. The thermoelectric device 3 includes at least one thermoelectric unit, such as... Figure 2 As shown, the thermoelectric unit includes a thermoelectric gel electrolyte and electrodes disposed on both sides of the thermoelectric gel electrolyte. The thermoelectric gel electrolyte provides good thermoelectric performance by introducing redox pairs with high Seebeck coefficients, and by adding water-soluble polymers to form a cross-linked network structure, it obtains excellent mechanical properties. The self-generating device also includes a greenhouse 6 disposed above the hot end (photothermal film layer) of the thermoelectric conversion component. The greenhouse 6 is composed of a photothermal film layer 1 and plexiglass, and its size can be selected as 15cm×5cm×5cm. The self-generating device is also provided with a heat-insulating bracket 7 to support the thermoelectric conversion component. The support column of the heat-insulating bracket 7 supports the device of this utility model to a certain height, achieving heat dissipation on the one hand, and effectively exchanging radiative heat with the atmospheric window on the other hand.

[0030] Preferably, the upper and lower surfaces of the hot and cold ends of the thermoelectric conversion component are connected by thermocouples in sequence, which can obtain the temperature and temperature difference of the hot end (photothermal thin film layer end) and the cold end (radiation cooling thin film layer end) in real time, and the current and voltage generated in the circuit after being amplified can be measured by a multimeter.

[0031] The preferred method for preparing the thermoelectric gel electrolyte is as follows: 10–40 wt% (by mass in the thermoelectric gel electrolyte) of a water-soluble polymer is dissolved in 50–100 ml of deionized water, and the solution is stirred at 50–100°C to ensure complete dissolution. Then, 10–30 ml of a 0.25 M–2.5 M redox couple solution is added. When the solution becomes transparent, 1–10 wt% (by mass in the thermoelectric gel electrolyte) of a conductive polymer is slowly injected, and stirring continues to prepare the thermoelectric gel electrolyte. Once the gel solution becomes homogeneous, it can be molded into the desired shape using various molds.

[0032] Because radiative cooling films possess high infrared emissivity within the atmospheric window (8-14 μm) band, they convert heat into electromagnetic waves of a specific wavelength without requiring any external energy input. This heat is then radiated directly into space through the "atmospheric window," achieving cooling and lower temperatures. Therefore, using functional materials with high emissivity and low solar absorption to reduce surface temperature effectively enables passive radiative cooling, keeping the cold end of the thermoelectric conversion component below the ambient atmospheric temperature.

[0033] The photothermal thin film formed by the photothermal material is attached to the upper surface of the upper heat-conducting layer 4. It has a high visible light absorption rate and a high photothermal conversion efficiency of 90-98%, which converts solar energy into heat. Under solar radiation, it raises the temperature of the substrate surface to achieve the required temperature difference.

[0034] Preferably, the methods for preparing the radiation-cooled thin film layer and the photothermal thin film layer are as follows:

[0035] (1) Apply thermal grease to the carrier and let it stand to form a thermally conductive layer;

[0036] (2) Prepare the corresponding precursor solution; wherein:

[0037] The preparation of the precursor solution for the radiation-cooled thin film includes: dissolving an organic polymer in an organic solvent at a temperature of 40–80°C, and then adding water at a mass ratio of organic polymer:organic solvent:water = 1:20–40:1. The organic solvent is preferably one or a combination of ethyl acetate, acetone, acetonitrile, and N,N-dimethylformamide. Then, 10–30 wt% of micro / nano particles are added, and the mixture is stirred vigorously for 4 hours to prepare a homogeneous precursor solution.

[0038] The precursor solution for the photothermal thin film layer includes: dissolving photothermal materials such as MXene or hydroxylated carbon-based materials in water, and obtaining a uniform suspension by stirring and sonication;

[0039] (3) Pour the prepared precursor solution into a container and then spray it vertically onto the heat-conducting surface. During spraying, the spraying distance of the spray gun is 200-250 cm, the air pressure of the nozzle is 5-6 MPa, and the discharge flow rate of the precursor solution is controlled at 5-6 mL / s. -1 Maintain a constant height and spray at a uniform speed to ensure the uniformity of the coating.

[0040] (4) After spraying, place the finished product in a fume hood (25°C) for 4 hours, and then transfer it to a forced-air oven and keep it at 35°C for 2 hours to remove excess moisture; forming a radiative cooling film layer or a photothermal film layer that adheres to the heat-conducting layer.

[0041] In one embodiment of this invention, a greenhouse 6 is further provided above the photothermal material film, which can further increase the hot end temperature of the thermoelectric device, thereby increasing the temperature difference. Near-infrared radiation in the solar spectrum can penetrate the glass to reach the inner surface of the greenhouse. The greenhouse gas filling the greenhouse has a strong near-infrared radiation absorption capacity, which will then transfer the energy upward into the atmosphere inside the greenhouse in the form of long-wave radiation. Long-wave radiation cannot penetrate the glass, and a large amount of heat accumulates in the atmosphere inside the greenhouse. The atmosphere inside and outside the greenhouse cannot conduct heat transfer due to the obstruction of the glass, so the heat remains inside the greenhouse to achieve a heat preservation effect. Furthermore, through contact and heat exchange with the photothermal film layer, the hot end temperature is further indirectly increased.

[0042] Greenhouse gases or phase change heat storage materials can be introduced into the chamber of greenhouse 6. Greenhouse gases will absorb and release infrared radiation to store infrared heat energy; after the phase change heat storage material reaches the phase change temperature, it will release latent heat of phase change, further aggravating the greenhouse effect caused by light and heat, thereby increasing the temperature difference.

[0043] In one embodiment of this utility model, a heat-insulating bracket 7 is also provided to support the self-generating device. The heat-insulating bracket 7 has an insulation layer on its surface and runs through the thermoelectric conversion component. It can prevent the heat generated at the hot end of the thermoelectric conversion component from being transferred to the cold end of the radiative cooling film, thereby preventing the cooling efficiency of the cold end from being affected.

[0044] In one embodiment of this invention, the upper and lower thermally conductive layers are thermally conductive silicone grease, connecting the thermoelectric conversion component, the radiative cooling film, and the photothermal material film, ensuring that the film does not peel off. The thermally conductive silicone grease is a highly thermally conductive and insulating silicone material that almost never hardens and can maintain its grease-like state for extended periods at temperatures ranging from -50℃ to +230℃. It possesses both excellent electrical insulation and excellent thermal conductivity, while also exhibiting stable chemical and physical properties, resistance to high and low temperatures, water, ozone, and weathering.

[0045] The working principle of this device is as follows: when sunlight shines on the surface of the photothermal film layer 1 as a heat source, the temperature at the hot end rises rapidly under the action of the greenhouse 6 and the photothermal material film. The radiative cooling film layer 2 quickly dissipates heat on the lower surface of the lower heat-conducting layer 5, forming a cold end. Due to the temperature difference between the upper and lower surfaces of the thermoelectric conversion component 3, a potential difference is generated in the circuit, thus generating current. The greater the temperature difference, the greater the output electrical energy. After being amplified by the voltage amplifier 8 through a closed current loop, it can be connected to the load 9.

[0046] Example 1

[0047] A self-generating device based on radiative cooling and photothermal materials includes a multi-walled carbon nanotube photothermal film layer 1 (film thickness approximately 30 μm, absorbance close to 97% under solar absorption spectrum), a radiative cooling film layer 2 composed of polyethylene oxide and barium sulfate (film thickness approximately 160 μm, average pore diameter approximately 1.2 μm; average solar spectral reflectance 96%), and a thermoelectric conversion component. Thermally conductive silicone grease serves as a thermally conductive layer connecting the corresponding films and the thermoelectric device. The self-generating device also includes a greenhouse 6 (15cm × 5cm × 5cm) filled with CO2 and placed above the multi-walled carbon nanotube photothermal film, and a polyurethane thermal insulation support 7. The thermoelectric conversion component consists of an upper thermally conductive layer 4, a thermoelectric device 3, and a lower thermally conductive layer 5, arranged from top to bottom. The thermoelectric device 3 includes 12 pairs of thermoelectric units connected in series. Each thermoelectric unit includes a thermoelectric gel electrolyte and electrodes disposed on both sides of the thermoelectric gel electrolyte. The thermoelectric gel electrolyte uses polythiophene as a conductive matrix and polyvinyl alcohol as a conductive network. 2- and SO3 2- As a redox pair, the output voltage signal of 12 thermoelectric units in series can be connected to the load 9 after being amplified by voltage amplifier 8 in a closed current loop.

[0048] Example 2

[0049] A self-generating device based on radiative cooling and photothermal materials includes a single-layer MXene photothermal film layer 1 (film thickness approximately 20 μm, absorbance close to 98% under solar absorption spectrum), a radiative cooling film layer 2 composed of polyvinylidene fluoride and alumina (film thickness approximately 156 μm, average pore diameter approximately 1.2 μm; average solar spectral reflectance 95%), and a thermoelectric conversion component. Thermally conductive silicone grease serves as a thermally conductive layer connecting the corresponding films to the thermoelectric conversion component. The self-generating device also includes an organic glass greenhouse 6 (15cm × 5cm × 5cm in size) filled with water vapor and a fiberglass thermal insulation support 7, disposed above the single-layer MXene photothermal film. The thermoelectric conversion component consists of an upper thermally conductive layer 4, a thermoelectric device 3, and a lower thermally conductive layer 5, arranged from top to bottom. The thermoelectric device 3 includes 12 pairs of thermoelectric units connected in series. Each thermoelectric unit includes a thermoelectric gel electrolyte and electrodes disposed on both sides of the thermoelectric gel electrolyte. The thermoelectric gel electrolyte uses polyaniline as a conductive matrix and polyacrylamide as a conductive network. [FeCN6] 3- and [FeCN6] 4- As a redox pair, the output voltage signal of 12 thermoelectric integrated units in series can be connected to the load 9 after being amplified by voltage amplifier 8 in a closed current loop.

[0050] Example 3

[0051] A self-generating device based on radiative cooling and photothermal materials includes a graphene photothermal thin film layer 1 (film thickness approximately 25 μm, absorbance close to 97% under solar absorption spectrum), a radiative cooling thin film layer 2 composed of poly(vinylidene fluoride-co-hexafluoropropylene) and silicon dioxide (film thickness approximately 140 μm, average pore diameter approximately 1.2 μm; average solar spectral reflectance 96%), and a thermoelectric conversion component. Thermally conductive silicone grease serves as a thermally conductive layer connecting the corresponding films to the thermoelectric conversion component. The self-generating device also includes... The system includes an organic glass greenhouse 6 (15cm × 5cm × 5cm) filled with methane, mounted above a graphene photothermal film, and a polystyrene insulation support 7. The thermoelectric conversion assembly, from top to bottom, consists of an upper heat-conducting layer 4, a thermoelectric device 3, and a lower heat-conducting layer 5. The thermoelectric device 3 includes 12 pairs of thermoelectric units connected in series. Each thermoelectric unit includes a thermoelectric gel electrolyte and electrodes disposed on both sides of the thermoelectric gel electrolyte. The thermoelectric gel electrolyte 3 uses polypyrrole as a conductive matrix and polyacrylamide as a conductive network. - and I3 - As a redox pair, the output voltage signal of 12 thermoelectric integrated units in series can be connected to the load 9 after being amplified by voltage amplifier 8 in a closed current loop.

[0052] Example 4

[0053] A self-generating device based on radiative cooling and photothermal materials includes a carbon black photothermal film layer 1 (film thickness approximately 17 μm, absorbance close to 95% under solar absorption spectrum), a radiative cooling film layer 2 composed of polylactic acid and calcium carbonate (film thickness approximately 170 μm, average pore diameter approximately 1.2 μm; average solar spectral reflectance 96%), and a thermoelectric conversion component. Thermally conductive silicone grease serves as a thermally conductive layer connecting the corresponding films to the thermoelectric conversion component. The self-generating device also includes an plexiglass greenhouse 6 (15cm × 5cm × 5cm in size) filled with liquid paraffin and an aluminum silicate insulation support 7, positioned above the carbon black photothermal film. The thermoelectric conversion component, from top to bottom, consists of an upper thermally conductive layer 4, a thermoelectric device 3, and a lower thermally conductive layer 5. The thermoelectric device 3 includes 12 pairs of thermoelectric units connected in series. Each thermoelectric unit includes a thermoelectric gel electrolyte and electrodes disposed on both sides of the thermoelectric gel electrolyte. The thermoelectric gel electrolyte 3 uses polyacetylene as a conductive matrix and polyvinyl alcohol as a conductive network. 2+ and Fe 3+ As a redox pair, the output voltage signal of 12 thermoelectric integrated units in series can be connected to the load 9 after being amplified by voltage amplifier 8 in a closed current loop.

[0054] Example 5

[0055] A self-generating device based on radiative cooling and photothermal materials includes a photothermal thin film layer 1 composed of copper-zinc particles (film thickness approximately 28 μm, absorbance close to 97% under solar absorption spectrum), a radiative cooling thin film layer 2 composed of polytetrafluoroethylene and titanium dioxide (film thickness approximately 150 μm, average pore diameter approximately 1.2 μm; average solar spectral reflectance 95%), and a thermoelectric conversion component. Thermally conductive silicone grease serves as a thermally conductive layer connecting the corresponding films to the thermoelectric conversion component. The self-generating device also includes an ozone-filled plexiglass greenhouse 6 (dimensions 15cm × 5cm × 5cm) and a polyurethane insulation support 7, positioned above the copper-zinc photothermal thin film. The thermoelectric conversion component, from top to bottom, consists of an upper thermally conductive layer 4, a thermoelectric device 3, and a lower thermally conductive layer 5. The thermoelectric device 3 includes 12 pairs of thermoelectric units connected in series. Each thermoelectric unit includes a thermoelectric gel electrolyte and electrodes disposed on both sides of the thermoelectric gel electrolyte. The thermoelectric gel electrolyte 3 uses polystyrene as a conductive matrix and polyacrylamide as a conductive network. [FeCN6] 3- and [FeCN6] 4- As a redox pair, the output voltage signal of 12 thermoelectric integrated units in series can be connected to the load 9 after being amplified by voltage amplifier 8 in a closed current loop.

[0056] Example 6

[0057] A self-generating device based on radiative cooling and photothermal materials includes a carbon fiber photothermal film layer 1 (film thickness approximately 20 μm, absorbance close to 96% under solar absorption spectrum), a radiative cooling film layer 2 composed of polyvinylidene fluoride and alumina (film thickness approximately 156 μm, average pore diameter approximately 1.2 μm; average solar spectral reflectance 95%), and a thermoelectric conversion component. Thermally conductive silicone grease serves as a thermally conductive layer connecting the corresponding films to the thermoelectric conversion component. The self-generating device also includes an organic glass greenhouse 6 (15cm × 5cm × 5cm in size) filled with water vapor and a fiberglass thermal insulation support 7, positioned above the carbon fiber photothermal film. The thermoelectric conversion component, from top to bottom, consists of an upper thermally conductive layer 4, a thermoelectric device 3, and a lower thermally conductive layer 5. The thermoelectric device 3 includes 12 pairs of thermoelectric units connected in series. Each thermoelectric unit includes a thermoelectric gel electrolyte and electrodes disposed on both sides of the thermoelectric gel electrolyte. The thermoelectric gel electrolyte 3 uses polyaniline as a conductive matrix and polyacrylamide as a conductive network. [FeCN6] 3- and [FeCN6] 4- As a redox pair, the output voltage signal of 12 thermoelectric integrated units in series can be connected to the load 9 after being amplified by voltage amplifier 8 in a closed current loop.

[0058] Example 7

[0059] A self-generating device based on radiative cooling and photothermal materials includes a single-layer MXene photothermal film layer 1 (film thickness approximately 20 μm, absorbance close to 98% under solar absorption spectrum), a radiative cooling film layer 2 composed of polylactic acid and calcium carbonate (film thickness approximately 170 μm, average pore diameter approximately 1.2 μm; average solar spectral reflectance 96%), and a thermoelectric conversion component. Thermally conductive silicone grease serves as a thermally conductive layer connecting the corresponding films to the thermoelectric conversion component. The self-generating device also includes an organic glass greenhouse 6 (15cm × 5cm × 5cm in size) filled with methane and an aluminum silicate insulation support 7, disposed above the single-layer MXene photothermal film. The thermoelectric conversion component consists of an upper thermally conductive layer 4, a thermoelectric device 3, and a lower thermally conductive layer 5, arranged from top to bottom. The thermoelectric device 3 includes 12 pairs of thermoelectric units connected in series. Each thermoelectric unit includes a thermoelectric gel electrolyte and electrodes disposed on both sides of the thermoelectric gel electrolyte. The thermoelectric gel electrolyte 3 uses polyacetylene as a conductive matrix and polyvinyl alcohol as a conductive network. 2+ and Fe 3+ As a redox pair, the output voltage signal of 12 thermoelectric integrated units in series can be connected to the load 9 after being amplified by voltage amplifier 8 in a closed current loop.

[0060] Example 8

[0061] A self-generating device based on radiative cooling and photothermal materials includes a carbonized lignin nanoparticle photothermal thin film layer 1 (film thickness approximately 23 μm, absorbance close to 94% under solar absorption spectrum), a radiative cooling thin film layer 2 composed of polytetrafluoroethylene and titanium dioxide (film thickness approximately 150 μm, average pore diameter approximately 1.2 μm; average solar spectral reflectance 95%), and a thermoelectric conversion component. Thermally conductive silicone grease serves as a thermally conductive layer connecting the corresponding films to the thermoelectric conversion component. The self-generating device also includes an plexiglass greenhouse 6 (15cm × 5cm × 5cm in size) filled with carbon dioxide and a polyurethane thermal insulation support 7, positioned above the carbonized lignin nanoparticles. The thermoelectric conversion component consists of an upper thermally conductive layer 4, a thermoelectric device 3, and a lower thermally conductive layer 5, arranged from top to bottom. The thermoelectric device 3 includes 12 pairs of thermoelectric units connected in series. Each thermoelectric unit includes a thermoelectric gel electrolyte and electrodes disposed on both sides of the thermoelectric gel electrolyte. The thermoelectric gel electrolyte 3 uses polystyrene as a conductive matrix and polyacrylamide as a conductive network. [FeCN6] 3- and [FeCN6] 4- As a redox pair, the output voltage signal of 12 thermoelectric integrated units in series can be connected to the load 9 after being amplified by voltage amplifier 8 in a closed current loop.

[0062] Example 9

[0063] A self-generating device based on radiative cooling and photothermal materials includes a single-layer MXene photothermal thin film layer 1 (film thickness approximately 20 μm, absorbance close to 98% under solar absorption spectrum), a radiative cooling thin film layer 2 composed of poly(vinylidene fluoride-co-hexafluoropropylene) and silicon dioxide (film thickness approximately 150 μm, average pore diameter approximately 1.2 μm; average solar spectral reflectance 96%), and a thermoelectric conversion component. Thermally conductive silicone grease serves as a thermally conductive layer connecting the corresponding thin films and the thermoelectric conversion component. The self-generating device also includes... An organic glass greenhouse 6 (15cm × 5cm × 5cm) filled with methane and a polystyrene insulation support 7 are arranged above a single-layer MXene photothermal film. The thermoelectric conversion assembly consists of an upper heat-conducting layer 4, a thermoelectric device 3, and a lower heat-conducting layer 5 from top to bottom. The thermoelectric device 3 includes 12 pairs of thermoelectric units connected in series. Each thermoelectric unit includes a thermoelectric gel electrolyte and electrodes disposed on both sides of the thermoelectric gel electrolyte. The thermoelectric gel electrolyte 3 uses polyaniline as a conductive matrix and polyacrylamide as a conductive network. [FeCN6] 3- and [FeCN6] 4- As a redox pair, the output voltage signal of 12 thermoelectric integrated units in series can be connected to the load 9 after being amplified by voltage amplifier 8 in a closed current loop.

[0064] Example 10

[0065] A self-generating device based on radiative cooling and photothermal materials includes a carbon black photothermal film layer 1 (film thickness approximately 17 μm, absorbance close to 95% under solar absorption spectrum), a radiative cooling film layer 2 composed of polyethylene oxide and barium sulfate (film thickness approximately 160 μm, average pore diameter approximately 1.2 μm; average solar spectral reflectance 96%), and a thermoelectric conversion component. Thermally conductive silicone grease serves as a thermally conductive layer connecting the corresponding films to the thermoelectric conversion component. The self-generating device also includes an organic glass greenhouse 6 (15cm × 5cm × 5cm in size) filled with CO2 and a polyurethane insulation support 7 disposed above the carbon black photothermal film. The thermoelectric conversion component consists of an upper thermally conductive layer 4, a thermoelectric device 3, and a lower thermally conductive layer 5, arranged from top to bottom. The thermoelectric device 3 includes 12 pairs of thermoelectric units connected in series. Each thermoelectric unit includes a thermoelectric gel electrolyte and electrodes disposed on both sides of the thermoelectric gel electrolyte. The thermoelectric gel electrolyte 3 uses polyacetylene as a conductive matrix and polyvinyl alcohol as a conductive network. 2+ and Fe 3+ As a redox pair, the output voltage signal of 12 thermoelectric integrated units in series can be connected to the load 9 after being amplified by voltage amplifier 8 in a closed current loop.

[0066] Comparative Example 1

[0067] The only difference between Comparative Example 1 and Example 1 is the presence or absence of an acrylic greenhouse 6.

[0068] A self-generating device based on radiative cooling and photothermal materials includes a multi-walled carbon nanotube photothermal thin film layer 1 (film thickness approximately 30 μm, absorbance close to 97% under solar absorption spectrum), a radiative cooling thin film layer 2 composed of polyethylene oxide and barium sulfate (film thickness approximately 160 μm, average pore diameter approximately 1.2 μm; average solar spectral reflectance 96%), and a thermoelectric conversion component. Thermally conductive silicone grease serves as a thermally conductive layer connecting the corresponding films to the thermoelectric conversion component. The self-generating device also includes a polyurethane thermal insulation support 7. The thermoelectric conversion component, from top to bottom, consists of an upper thermally conductive layer 4, a thermoelectric device 3, and a lower thermally conductive layer 5. The thermoelectric device 3 includes 12 pairs of thermoelectric units connected in series. Each thermoelectric unit includes a thermoelectric gel electrolyte and electrodes disposed on both sides of the thermoelectric gel electrolyte. The thermoelectric gel electrolyte 3 uses polythiophene as a conductive matrix and polyvinyl alcohol as a conductive network. 2- and SO3 2- As a redox pair, the output voltage signal of 12 thermoelectric integrated units in series can be connected to the load 9 after being amplified by voltage amplifier 8 in a closed current loop.

[0069] Comparative Example 2

[0070] The only difference between Comparative Example 2 and Example 2 is the presence or absence of an acrylic greenhouse 6.

[0071] A self-generating device based on radiative cooling and photothermal materials includes a single-layer MXene photothermal thin film layer 1 (film thickness approximately 20 μm, absorbance close to 98% under solar absorption spectrum), a radiative cooling thin film layer 2 composed of polyvinylidene fluoride and alumina (film thickness approximately 156 μm, average pore diameter approximately 1.2 μm; average solar spectral reflectance 95%), and a thermoelectric conversion component. Thermally conductive silicone grease serves as a thermally conductive layer connecting the corresponding films to the thermoelectric conversion component. The self-generating device also includes a glass fiber thermal insulation support 7. The thermoelectric conversion component, from top to bottom, consists of an upper thermally conductive layer 4, a thermoelectric device 3, and a lower thermally conductive layer 5. The thermoelectric device 3 includes 12 pairs of thermoelectric units connected in series. Each thermoelectric unit includes a thermoelectric gel electrolyte and electrodes disposed on both sides of the thermoelectric gel electrolyte. The thermoelectric gel electrolyte 3 uses polyaniline as a conductive matrix and polyacrylamide as a conductive network. [FeCN6] 3- and [FeCN6] 4- As a redox pair, the output voltage signal of 12 thermoelectric integrated units in series can be connected to the load 9 after being amplified by voltage amplifier 8 in a closed current loop.

[0072] Comparative Example 3

[0073] The only difference between Comparative Example 3 and Example 3 is the presence or absence of the photothermal thin film layer 1.

[0074] A self-generating device based on radiative cooling and photothermal materials includes a radiative cooling thin film layer 2 (approximately 140 μm thick, with an average pore diameter of approximately 1.2 μm and an average solar spectral reflectance of 96%) composed of poly(vinylidene fluoride-co-hexafluoropropylene) and silicon dioxide, and a thermoelectric conversion component. Thermally conductive silicone grease serves as a thermally conductive layer connecting the corresponding film and the thermoelectric conversion component. The self-generating device also includes an plexiglass greenhouse 6 (15 cm × 5 cm × 5 cm) filled with methane and a polystyrene insulation support 7, positioned above the original photothermal film. The thermoelectric conversion component consists of an upper thermally conductive layer 4, a thermoelectric device 3, and a lower thermally conductive layer 5, arranged from top to bottom. The thermoelectric device 3 includes 12 pairs of thermoelectric units connected in series. Each thermoelectric unit includes a thermoelectric gel electrolyte and electrodes disposed on both sides of the thermoelectric gel electrolyte. The thermoelectric gel electrolyte 3 uses polypyrrole as a conductive matrix and polyacrylamide as a conductive network. - and I3 - As a redox pair, the output voltage signal of 12 thermoelectric integrated units in series can be connected to the load 9 after being amplified by voltage amplifier 8 in a closed current loop.

[0075] Comparative Example 4

[0076] The only difference between Comparative Example 4 and Example 4 is the presence or absence of the photothermal thin film layer 1.

[0077] A self-generating device based on radiative cooling and photothermal materials includes a radiative cooling thin film layer 2 (approximately 170 μm thick, average pore diameter approximately 1.2 μm; average solar spectral reflectivity 96%) composed of polylactic acid and calcium carbonate, and a thermoelectric conversion component. Thermally conductive silicone grease serves as a thermally conductive layer connecting the corresponding film and the thermoelectric conversion component. The self-generating device also includes an plexiglass greenhouse 6 (15cm × 5cm × 5cm in size) filled with liquid paraffin and an aluminum silicate insulation support 7, positioned above the original photothermal film. The thermoelectric conversion component consists of an upper thermally conductive layer 4, a thermoelectric device 3, and a lower thermally conductive layer 5, arranged from top to bottom. The thermoelectric device 3 includes 12 pairs of thermoelectric units connected in series. Each thermoelectric unit includes a thermoelectric gel electrolyte and electrodes disposed on both sides of the thermoelectric gel electrolyte. The thermoelectric gel electrolyte 3 uses polyacetylene as a conductive matrix and polyvinyl alcohol as a conductive network. 2+ and Fe 3+ As a redox pair, the output voltage signal of 12 thermoelectric integrated units in series can be connected to the load 9 after being amplified by voltage amplifier 8 in a closed current loop.

[0078] Comparative Example 5

[0079] The only difference between Comparative Example 5 and Example 5 is the presence or absence of a radiation cooling film 2.

[0080] A self-generating device based on radiative cooling and photothermal materials includes a photothermal thin film layer 1 composed of copper-zinc particles (film thickness approximately 28 μm, absorbance close to 97% under the solar absorption spectrum) and a thermoelectric conversion component. Thermally conductive silicone grease serves as a thermally conductive layer connecting the corresponding film and the thermoelectric conversion component. The self-generating device also includes an ozone-filled plexiglass greenhouse 6 (15cm × 5cm × 5cm in size) and a polyurethane insulation support 7, positioned above the copper-zinc photothermal thin film. The thermoelectric conversion component, from top to bottom, consists of an upper thermally conductive layer 4, a thermoelectric device 3, and a lower thermally conductive layer 5. The thermoelectric device 3 includes 12 pairs of thermoelectric units connected in series. Each thermoelectric unit includes a thermoelectric gel electrolyte and electrodes disposed on both sides of the thermoelectric gel electrolyte. The thermoelectric gel electrolyte 3 uses polystyrene as a conductive matrix and polyacrylamide as a conductive network. [FeCN6] 3- and [FeCN6] 4- As a redox pair, the output voltage signal of 12 thermoelectric integrated units in series can be connected to the load 9 after being amplified by voltage amplifier 8 in a closed current loop.

[0081] Comparative Example 6

[0082] The only difference between Comparative Example 6 and Example 6 is the presence or absence of a radiation cooling film 2.

[0083] A self-generating device based on radiative cooling and photothermal materials includes a carbon fiber photothermal film layer 1 (film thickness approximately 20 μm, absorbance close to 96% under the solar absorption spectrum) and a thermoelectric conversion component. Thermally conductive silicone grease serves as a thermally conductive layer connecting the corresponding film and the thermoelectric conversion component. The self-generating device also includes an organic glass greenhouse 6 (15cm × 5cm × 5cm in size) filled with water vapor and a fiberglass insulation support 7, positioned above the carbon fiber photothermal film. The thermoelectric conversion component, from top to bottom, consists of an upper thermally conductive layer 4, a thermoelectric device 3, and a lower thermally conductive layer 5. The thermoelectric device 3 includes 12 pairs of thermoelectric units connected in series. Each thermoelectric unit includes a thermoelectric gel electrolyte and electrodes disposed on both sides of the thermoelectric gel electrolyte. The thermoelectric gel electrolyte 3 uses polyaniline as a conductive matrix and polyacrylamide as a conductive network. [FeCN6] 3- and [FeCN6] 4- As a redox pair, the output voltage signal of 12 thermoelectric integrated units in series can be connected to the load 9 after being amplified by voltage amplifier 8 in a closed current loop.

[0084] The thermoelectric gel electrolyte designed in each embodiment of this utility model, taking a rectangular structure as an example, has an effective length of 2cm, a width of 2cm, and a thickness of 2mm. Copper sheets are used as electrodes connected to both ends of the thermoelectric gel electrolyte. A Fluke 15B+ is used to measure the resistance at both ends of the thermoelectric gel electrolyte. A low-voltage power supply and a YGX-300V-3A temperature monitoring instrument are used to control the temperature difference between the left and right ends of the sample. Test conditions: Time: 10:30 AM to 2:30 PM, September 17, 2024; Location: Moganshan Campus, Zhejiang University of Technology; Weather: Sunny; Average solar irradiance: 1560W / m² 2 With an air temperature of 25.2–34.1℃ and a relative humidity of 75%, the measured temperature difference and integrated thermoelectric power performance are shown in Table 1.

[0085] Table 1. Performance summary of each embodiment and comparative example.

[0086]

[0087]

[0088] The above comparison shows that the temperature difference and output power of the integrated thermoelectric element in Comparative Examples 1 and 2 of this invention are significantly better than those in Comparative Examples 3-6, proving that the device of this invention can create a large temperature difference between the two ends of the thermoelectric conversion component, generate a large electromotive force, and has low cost and high efficiency. At the same time, based on this, the embodiment of this invention, because it is equipped with a greenhouse, can further significantly create a larger temperature difference and further improve the output power of the integrated thermoelectric element on the basis of Comparative Examples 1 and 2, thus having more significant advantages.

[0089] In addition, the performance of some embodiments and comparative examples of this utility model was tested under nighttime conditions without a heat source. The test conditions were: time from 19:30 to 22:30 on September 17, 2024, location: Moganshan Campus of Zhejiang University of Technology, weather: partly cloudy, temperature 28.1–32.0℃, average relative humidity approximately 80%. The measured temperature difference and integrated thermoelectric power performance are shown in Table 2.

[0090] Table 2 Summary of performance of each embodiment and comparative example under nighttime heat-free conditions.

[0091]

[0092]

[0093] The above comparison shows that, without a heat source, the embodiments of this invention can maintain a temperature difference between 14.5 and 24.0°C, with an output power between 0.76 and 1.71 μW. Comparative Examples 1 and 2, lacking a greenhouse, have a temperature difference of approximately 2°C between their hot and cold ends, resulting in extremely low output power from the integrated thermoelectric element. Comparative Examples 3 and 4, equipped with a greenhouse, can store and preserve the solar heat acquired during the day, and the radiant cooling film further reduces the cold end temperature, maintaining a temperature difference of approximately 6°C and outputting only a small amount of power. Comparative Examples 5 and 6, although equipped with a greenhouse for heat storage, lack a radiant cooling film, resulting in a temperature difference of approximately 3°C and also only a very small output power.

[0094] The embodiments described above are merely preferred solutions of this utility model and are not intended to limit this utility model in any way. Other variations and modifications are possible without departing from the technical solutions described in the claims.

Claims

1. A self-generating power device based on radiative cooling and photothermal materials, characterized in that, It includes a photothermal thin film layer (1), a radiation cooling thin film layer (2) and a thermoelectric conversion component. The thermoelectric conversion component includes an upper heat-conducting layer (4), a thermoelectric device (3) and a lower heat-conducting layer (5) from top to bottom. The thermoelectric device (3) includes at least one thermoelectric unit. The thermoelectric unit includes a thermoelectric gel electrolyte and electrodes disposed on both sides of the thermoelectric gel electrolyte. The upper heat-conducting layer (4) is disposed adjacent to the photothermal thin film layer (1), and the lower heat-conducting layer (5) is disposed adjacent to the radiation cooling thin film layer (2).

2. The self-generating power device based on radiative cooling and photothermal materials according to claim 1, characterized in that, The aforementioned radiation cooling film is a composite film with a reflectivity of not less than 90% in the solar spectrum and an infrared emissivity of not less than 90% in the atmospheric window.

3. The self-generating power device based on radiative cooling and photothermal materials according to claim 2, characterized in that, The thickness of the radiation cooling thin film layer (2) is 120-170 μm.

4. The self-generating power device based on radiative cooling and photothermal materials according to claim 1, characterized in that, The absorbance of the photothermal thin film layer (1) under the solar absorption spectrum is not less than 90%.

5. The self-generating power device based on radiative cooling and photothermal materials according to claim 4, characterized in that, The thickness of the photothermal thin film layer (1) is 10~30μm.

6. The self-generating power device based on radiative cooling and photothermal materials according to claim 1, characterized in that, A greenhouse (6) is provided above the photothermal film layer (1). The greenhouse (6) consists of a chamber made of the photothermal film layer (1) and plexiglass, and a greenhouse material filled into the chamber.

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