Preparation method of radiation cooling friction nanometer power generation coating

Abstract

The invention discloses a preparation method of a radiation cooling friction nanometer power generation coating, and relates to the technical field of energy conservation and heat management of intelligent residences. The method comprises the following steps: weighing required amounts of titanium oxide (A) powder and titanium oxide (A1) powder, uniformly mixing the two kinds of powder through a magnetic stirrer or an ultrasonic oscillator, mixing the PDMS base material and the curing agent according to the required amount, and gradually adding the mixed titanium oxide (A2) nano powder into the PDMS (B) mixed solution; by adopting a novel material, the raindrop energy collecting efficiency and applicability are improved, and a foundation is laid for practicability of the device. Meanwhile, the problem that a traditional water drop friction nanometer generator can only play a role in energy conservation and emission reduction in cloudy and rainy days is solved, efficient heat management is achieved in non-rainy days, the environment temperature is reduced, the comfort degree of the living environment is improved, and a new thought and material technology are provided for design and development of an annual high-adaptability raindrop energy collection system.

Description

Technical Field

[0001] The present invention relates to the technical field of energy saving and thermal management of intelligent houses, and in particular to a method for preparing a radiation cooling friction nano power generation coating. Background Art

[0002] With the rapid development of science and technology, energy issues are becoming increasingly important. The use of traditional energy sources such as fossil fuels such as coal and oil is not only limited in resources, but also the pollutants produced by their combustion have caused great damage to the environment. Therefore, the development of new, renewable, and environmentally friendly energy technologies has become a global consensus. Among the many renewable energy technologies, environmental energy harvesting technology has attracted much attention due to its unique advantages. This type of technology captures weak energy in the environment (such as light energy, wind energy, heat energy, vibration energy) and converts it into electrical energy or mechanical energy to power electronic devices.

[0003] The raindrop energy collection system in the prior art is often only applicable to specific climate environments. It is impossible to collect energy in dry climates such as sunny days, resulting in low energy-saving efficiency throughout the year and inability to be put into large-scale urban use. At the same time, the raindrop energy collection system often has the problem of low energy conversion efficiency due to the lack of high-performance solid-liquid electrification materials, that is, the kinetic energy generated when raindrops fall cannot be effectively converted into electrical energy or mechanical energy, and the raindrop energy collection system is often greatly affected by environmental factors (such as wind speed, temperature, humidity), thus showing poor adaptability. In response to the above problems, the inventor proposes a method for preparing a radiation cooling friction nano-power generation coating to solve the above problems. Summary of the invention

[0004] In order to solve the problem of low output and energy conversion efficiency of raindrop energy collection system, as well as the challenge of inability to effectively collect ambient energy in sunny environment and low energy conversion efficiency throughout the year; the purpose of the present invention is to provide a method for preparing a radiation cooling friction nano-power generation coating.

[0005] In order to solve the above technical problems, the present invention adopts the following technical solution: a method for preparing a radiation cooling friction nano power generation coating, comprising the following steps:

[0006] S1: Weigh the required amount of titanium oxide (A) powder and titanium oxide (A1) powder, and mix the two powders evenly using a magnetic stirrer or an ultrasonic oscillator;

[0007] S2: Mix the required amount of PDMS base material and curing agent, gradually add the mixed titanium oxide (A2) nanopowder into the PDMS (B) mixed solution, stir while adding to ensure uniform dispersion, and remove bubbles in the mixed solution by vacuum degassing instrument;

[0008] S3: Pour the mixed PDMS-titanium oxide nano-solution into the mold and place the mold in an oven until the film surface becomes solid but still has a certain stickiness;

[0009] S4: Gently lay the PTFE (C) porous membrane (thickness ranges from 20 to 200 μm) on the surface of the pre-cured PDMS-titanium oxide membrane, ensuring that there are no bubbles and wrinkles, and then continue to cure in an oven until the entire composite membrane is completely cured;

[0010] S5: After the composite film is cured, the composite film is taken out of the oven, cooled to room temperature, and finally the composite film is carefully taken out of the mold to avoid damage.

[0011] Preferably, the volume ratio of the titanium oxide (A) powder to the titanium oxide (A1) powder is 5:1-9:1.

[0012] Preferably, the ratio of the PDMS (B) to its curing agent may be 7:1-10:1.

[0013] Preferably, the film thickness of the PDMS-titanium oxide nano-solution after curing needs to be between 500-900 microns.

[0014] Preferably, the oven temperature needs to be maintained at 60-100 degrees Celsius for 0.5-2 hours.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] 1. The present invention integrates raindrop energy collection and radiation cooling into a new type of material, achieving multifunctional unity and coordination, and greatly improving the efficiency and applicability of the material;

[0017] 2. Through unique material design and structural optimization, the present invention can efficiently convert the kinetic energy of raindrops into electrical energy, solving the problem of low energy conversion efficiency of traditional raindrop energy collection equipment. The technology can work stably under various weather conditions, not just on rainy days, and improves the continuity and reliability of energy saving;

[0018] 3. The radiation cooling coating in the present invention has high spectral reflectivity and infrared emissivity, which can effectively reduce the temperature of the building roof, reduce air conditioning energy consumption, and improve indoor comfort. The coating material is environmentally friendly, durable, suitable for various building surfaces, and has good application prospects;

[0019] 4. The present invention uses PDMS (polydimethylsiloxane) and TiO2 (titanium dioxide) as the main materials, and forms a multifunctional coating with excellent performance through a specific preparation process. The material combination and preparation process ensure that the coating has excellent mechanical properties, chemical stability and environmental adaptability, and can meet the use requirements under various complex environmental conditions;

[0020] 5. The present invention improves the collection efficiency and applicability of raindrop energy by adopting new materials, laying a foundation for the practical application of the device. At the same time, it makes up for the problem that traditional water drop friction nanogenerators can only play an energy-saving and emission-reduction role on rainy days, and achieves efficient thermal management on non-rainy days, reduces the ambient temperature, and improves the comfort of the living environment, providing new ideas and material technologies for the design and development of highly adaptable raindrop energy collection systems throughout the year. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0022] Figure 1 It is a schematic diagram of the cross-sectional structure of the present invention.

[0023] Figure 2 Schematic diagram of the effect of the water droplet volume characteristics on the designed RC-DEG output performance in the present invention.

[0024] Figure 3 It is a schematic diagram of the spectral reflectance and infrared emissivity coating effects of the present invention. DETAILED DESCRIPTION

[0025] The technical scheme in the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiment of the present invention. Obviously, the described embodiment is only a part of the embodiment of the present invention, not all of the embodiments. Based on the embodiment of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0026] Example: Figure 1-3 As shown, the present invention provides a technical solution: a method for preparing a radiation cooling friction nano power generation coating, comprising the following steps:

[0027] S1: Weigh the required amount of titanium oxide (A) powder and titanium oxide (A1) powder, and mix the two powders evenly using a magnetic stirrer or an ultrasonic oscillator;

[0028] S2: Mix the required amount of PDMS base material and curing agent, gradually add the mixed titanium oxide (A2) nanopowder into the PDMS (B) mixed solution, stir while adding to ensure uniform dispersion, and remove bubbles in the mixed solution by vacuum degassing instrument;

[0029] S3: Pour the mixed PDMS-titanium oxide nano-solution into the mold and place the mold in an oven until the film surface becomes solid but still has a certain stickiness;

[0030] S4: Gently lay the PTFE (C) porous membrane (thickness ranges from 20 to 200 μm) on the surface of the pre-cured PDMS-titanium oxide membrane, ensuring that there are no bubbles and wrinkles, and then continue to cure in an oven until the entire composite membrane is completely cured;

[0031] S5: After the composite film is cured, the composite film is taken out of the oven, cooled to room temperature, and finally the composite film is carefully taken out of the mold to avoid damage.

[0032] The volume ratio of titanium oxide (A) powder to titanium oxide (A1) powder is 5:1-9:1.

[0033] By adopting the above technical solution, it is necessary to ensure uniform stirring and mixing during all operations to obtain uniform distribution of nanopowders.

[0034] The ratio of PDMS (B) to its curing agent may be 7:1-10:1.

[0035] By adopting the above technical solution, the mixing ratio can be appropriately adjusted and modified according to actual requirements.

[0036] The film thickness of the PDMS-titanium oxide nano-solution after curing needs to be between 500-900 microns.

[0037] By adopting the above technical solution, the temperature and time of pre-curing and final curing should be appropriately adjusted according to the specific experimental conditions to ensure the best curing effect.

[0038] The oven temperature needs to be maintained at 60-100 degrees Celsius and the time needs to be 0.5-2 hours.

[0039] By adopting the above technical solution, the PTFE porous membrane should be applied gently to avoid introducing bubbles and wrinkles that affect the performance of the final membrane.

[0040] Working principle: The PDMS / TiO2 coating exhibits high spectral reflectivity (94%) and infrared emissivity (93%). During the day, the radiation cooling layer reduces heat absorption by reflecting sunlight and dissipates heat into outer space by emitting infrared radiation, achieving a sub-ambient temperature cooling effect. When the solar irradiance is highest, the temperature of the PDMS / TiO2 coating is 6.8°C lower than the ambient temperature. At night, the cooling effect is even better, and the temperature of the PDMS / TiO2 coating can be up to 11.5°C lower than the ambient temperature.

[0041] When raindrops hit the triboelectric nanogenerator layer, electrical energy is generated and stored in the energy storage device of the smart home. Working mechanism of radiative cooling water droplet triboelectric nanogenerator (RC-DEG) prepared by PDMS / TiO2 coating In the initial stage, the water droplets are positively pre-charged due to various environmental factors such as the friction electrification of water droplets / air. When the positively charged water droplets come into contact with the triboelectric layer, the water droplets change from spherical to pancake-shaped, and the charge accumulation is maximum when the water droplets approach the maximum diffusion area. The instantaneous discharge at the contact with the top electrode causes the electrons to transfer from the back electrode to the top electrode, generating an instantaneous positive current and achieving electrostatic equilibrium. The water droplets then begin to bounce off the surface, causing the water droplets to move away from the top electrode, breaking the electrostatic equilibrium. The electrons in the top electrode flow back to the back electrode, generating an instantaneous negative current. Through continuous water drop collisions, periodic power output can be generated.

[0042] In addition, the effects of the droplet volume characteristics on the output performance of the designed RC-DEG are systematically investigated, e.g. Figure 2 As shown in the figure, the open circuit voltage and short circuit current increase with the increase of charge transfer area, the volume of water droplets increases continuously, and the charge transfer area increases. The maximum values ​​obtained are 27.8V and 18.2μA. Figure 3 The spectral reflectance (ρ) and infrared emissivity (ε) of PDMS / TiO2 coatings with a thickness of approximately 200 μm are shown, based on the standardized ASTM-G173 global solar spectrum and LWIR atmospheric transparency window. The PDMS / TiO2 coating exhibits a selective spectral response with a special angle-dependent average solar spectral reflectance ρ and infrared emissivity ε under solar radiation. The designed coating has a ρ of 94% and an ε of 93%. The 24-hour ambient temperature and the temperature of the PDMS / TiO2 selected coating are compared, and the solar irradiance is recorded in real time. At the highest solar irradiance, the PDMS / TiO2 coating temperature is 6.8°C lower than the ambient temperature. The PDMS / TiO2 coating temperature is up to 11.5°C lower than the ambient temperature throughout the day.

[0043] The present invention adopts an integrated coating design to construct a composite energy-saving material with high-performance solid-liquid electrification and radiation cooling. The structure is simple and compact, and it is easy to install and maintain. The special design between the layers realizes efficient energy conversion and transmission, while ensuring the stability and durability of the structure. After the coating system of the present invention is applied to the roof or exterior wall surface of the smart house, all-weather energy saving and thermal management can be achieved. On sunny days, the surface temperature is reduced by the radiation cooling layer, and heat continues to be radiated at night; when raindrops hit, the friction nanogenerator layer generates electricity.

[0044] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A method for preparing a radiation cooling friction nano-power generation coating, characterized in that: The following steps are involved: S1: Weigh the required amount of titanium oxide (A) powder and titanium oxide (A1) powder, and mix the two powders evenly using a magnetic stirrer or an ultrasonic oscillator; S2: Mix the required amount of PDMS base material and curing agent, gradually add the mixed titanium oxide (A2) nanopowder into the PDMS (B) mixed solution, stir while adding to ensure uniform dispersion, and remove bubbles in the mixed solution by vacuum degassing instrument; S3: Pour the mixed PDMS-titanium oxide nano-solution into the mold and place the mold in an oven until the film surface becomes solid but still has a certain stickiness; S4: Gently lay the PTFE (C) porous membrane (thickness ranges from 20 to 200 μm) on the surface of the pre-cured PDMS-titanium oxide membrane, ensuring that there are no bubbles and wrinkles, and then continue to cure in an oven until the entire composite membrane is completely cured; S5: After the composite film is cured, the composite film is taken out of the oven, cooled to room temperature, and finally the composite film is carefully taken out of the mold to avoid damage.

2. The method for preparing a radiation cooling friction nano power generation coating according to claim 1, characterized in that: The volume ratio of the titanium oxide (A) powder to the titanium oxide (A1) powder is 5:1-9:

1.

3. The method for preparing a radiation cooling friction nano power generation coating according to claim 1, characterized in that: The ratio of the PDMS (B) to its curing agent may be 7:1-10:

1.

4. The method for preparing a radiation cooling friction nano power generation coating according to claim 1, characterized in that: The film thickness of the PDMS-titanium oxide nano-solution after curing needs to be between 500-900 microns.

5. The method for preparing a radiation cooling friction nano power generation coating according to claim 1, characterized in that: The oven temperature needs to be maintained at 60-100 degrees Celsius, and the time needs to be 0.5-2 hours.

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