WO2020207407A1 - 一种光谱自适应的白天太阳能集热夜间辐射制冷涂层材料 - Google Patents

一种光谱自适应的白天太阳能集热夜间辐射制冷涂层材料 Download PDF

Info

Publication number
WO2020207407A1
WO2020207407A1 PCT/CN2020/083722 CN2020083722W WO2020207407A1 WO 2020207407 A1 WO2020207407 A1 WO 2020207407A1 CN 2020083722 W CN2020083722 W CN 2020083722W WO 2020207407 A1 WO2020207407 A1 WO 2020207407A1
Authority
WO
WIPO (PCT)
Prior art keywords
coating material
layer
refractive index
heat collection
band
Prior art date
Application number
PCT/CN2020/083722
Other languages
English (en)
French (fr)
Inventor
裴刚
敖显泽
胡名科
赵斌
陈诺
Original Assignee
中国科学技术大学
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 中国科学技术大学 filed Critical 中国科学技术大学
Publication of WO2020207407A1 publication Critical patent/WO2020207407A1/zh

Links

Images

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24S—SOLAR HEAT COLLECTORS; SOLAR HEAT SYSTEMS
    • F24S70/00—Details of absorbing elements
    • F24S70/20—Details of absorbing elements characterised by absorbing coatings; characterised by surface treatment for increasing absorption
    • F24S70/225—Details of absorbing elements characterised by absorbing coatings; characterised by surface treatment for increasing absorption for spectrally selective absorption
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24S—SOLAR HEAT COLLECTORS; SOLAR HEAT SYSTEMS
    • F24S70/00—Details of absorbing elements
    • F24S70/20—Details of absorbing elements characterised by absorbing coatings; characterised by surface treatment for increasing absorption
    • F24S70/25—Coatings made of metallic material
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24S—SOLAR HEAT COLLECTORS; SOLAR HEAT SYSTEMS
    • F24S70/00—Details of absorbing elements
    • F24S70/30—Auxiliary coatings, e.g. anti-reflective coatings
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E10/00—Energy generation through renewable energy sources
    • Y02E10/40—Solar thermal energy, e.g. solar towers

Definitions

  • the invention belongs to the technical field of energy utilization, and specifically relates to the comprehensive application of solar heat collection and radiant refrigeration with variable spectral selectivity, and more specifically a spectral self-adaptive coating material for daytime solar heat collection and night radiant refrigeration.
  • the sun is the largest heat and light source of the earth.
  • the utilization of solar energy mainly includes photovoltaic utilization, photothermal utilization and photochemical utilization.
  • Solar heat collection technology (light and heat utilization) is one of the most mature technologies for solar energy utilization.
  • One of the research focuses of solar heat collection technology is to obtain high-quality solar selective absorption coating materials.
  • the solar selective absorption coating materials have high absorption (emission) rate in the solar radiation band (0.3 ⁇ 3 ⁇ m), and the infrared wavelength is greater than 3 ⁇ m.
  • the band has a low absorption (emission) rate.
  • the outer space temperature of the earth's atmosphere is close to absolute zero, which is a natural source of cold.
  • Objects on the ground can perform radiation heat exchange with the universe through the "atmospheric window” band (here: 8-13 ⁇ m) to achieve a certain cooling effect, which is called radiant cooling.
  • the ideal radiant refrigeration coating material has a high emission (absorption) rate in the "atmospheric window” band (8-13 ⁇ m) and low emission (absorption) rate in other bands.
  • Radiant refrigeration is a passive, zero-energy, zero-pollution refrigeration method, which has positive significance for building cooling, energy saving and environmental protection, and has received extensive attention in recent years.
  • the solar heat collection technology is very mature, it is subject to the day and night change, and the solar heat collector is idle at night; on the other hand, although the night radiant cooling technology is relatively mature, the solar radiation power is too large during the day (order of 10 3 W/m 2 , about 10 times the radiant cooling power), radiant cooling is difficult to achieve during the day, or the cooling power is very low during the day.
  • This kind of coating material has the same spectral characteristics in daytime and night time, so that in the daytime solar heat collection mode, the coating material has a high absorption (emission) rate in the "atmospheric window” band (8-13 ⁇ m). Radiation heat loss, compared with traditional solar selective absorption coating materials, the thermal efficiency is lower.
  • the present invention provides a spectrum self-adaptive coating material for solar heat collection during the day and radiation at night.
  • a spectrum-adaptive daytime solar heat collection and nighttime radiation refrigeration coating material at least includes a base layer, an infrared emission layer, a phase change layer and an anti-reflection layer which are sequentially arranged from bottom to top;
  • the base layer is a material that has a high absorption rate for the solar radiation band of 0.3 to 3 ⁇ m (high absorption rate means that the average absorption rate of the material in the solar radiation band of 0.3 to 3 ⁇ m is greater than 0.7) or a material that has a high solar radiation band of 0.3 to 3 ⁇ m.
  • Reflectivity refers to metal materials with an average reflectivity greater than 0.7 in the solar radiation band of 0.3-3 ⁇ m
  • the infrared emitting layer is a material with high emissivity to the "atmospheric window" band of 8-13 ⁇ m (high emissivity means that the average emissivity of the material in the 8-13 ⁇ m band is greater than 0.5);
  • the phase change layer is a material with thermally induced phase change characteristics
  • the anti-reflection layer is a single layer of low-refractive index material or a multilayer alternately overlapping structure composed of a low-refractive index material and a high-refractive index material;
  • the coating material corresponds to different spectral selectivities in the daytime solar heat collection and night radiant cooling modes, and can change its spectral selectivity according to the temperature change of the coating material through the principle of thermally induced phase change to meet the high efficiency solar heat collection during the day , Spectral demand for radiant cooling at night.
  • the coating material absorbs solar radiation during the day, the temperature rises, and the temperature of the coating material is higher than the phase change temperature of the thermally induced phase change material, the coating material is in a high-efficiency solar heat collection mode, and the coating material is 0.3 to 3 ⁇ m
  • the absorption rate of the solar radiation band is greater than 0.85, and the emissivity in the infrared band of 3-25 ⁇ m is less than 0.4; at night, the temperature of the coating material is lower than the phase change temperature of the thermally induced phase change material, and the coating material is in the radiation cooling mode.
  • the emissivity of the coating material in the "atmospheric window" band of 8-13 ⁇ m is greater than 0.7, and the absorptivity of the solar radiation band of 0.3-3 ⁇ m is greater than 0.8.
  • the solar radiation waveband (0.3-3 ⁇ m) has a high absorptivity material from one of blue titanium, black chrome and black paint.
  • the metal material with high reflectivity in the solar radiation band of 0.3-3 ⁇ m is one of aluminum, silver, copper, tungsten, chromium, molybdenum, titanium, nickel or cobalt, and the thickness is 100-500 nm.
  • the material with high emissivity in the 8-13 ⁇ m band is one of glass, quartz or alumina single crystal.
  • the material with thermally induced phase change characteristics is vanadium dioxide, and the thickness of the phase change layer is 10-500 nm, preferably 80-300 nm.
  • the low refractive index material is a material with a refractive index less than or equal to 2 at a wavelength of 0.5 ⁇ m, and the thickness of the anti-reflection layer is 10 to 500 nm, preferably 10 to 200 nm.
  • An example of the low refractive index material may be one of silica or alumina.
  • the high refractive index material is a material with a refractive index greater than 2 at a wavelength of 0.5 ⁇ m, and an example of the high refractive index material may be vanadium dioxide.
  • the thickness of the anti-reflection layer is 10 to 500 nm, preferably 10 to 200 nm.
  • the alternately overlapping structure is composed of a layer of low refractive index material, a layer of high refractive index material and a layer of low refractive index material sequentially overlapping.
  • Figure 1 is a diagram of the working principle of a spectrally adaptive daytime solar heat collection and night radiation refrigeration coating material
  • FIG. 2 is a schematic diagram of the structure of the coating material of the present invention, and the serial numbers in the figure are: base layer 1, infrared emitting layer 2, phase change layer 3, anti-reflection layer 4.
  • Fig. 3 is a graph of the spectral absorption (emission) rate of the coating material of Example 1 in the daytime heat collection mode and the night cooling mode.
  • Figure 4 is a graph of the spectral absorption (emission) rate of the coating material of Comparative Example 1 in the daytime heat collection mode and the night cooling mode.
  • Example 5 is a graph of the spectral absorption (emission) rate of the coating material of Example 2 in the daytime heat collection mode and the night cooling mode.
  • Figure 6 is a graph of the spectral absorption (emission) rate of the coating material of Example 3 in the daytime heat collection mode and the night cooling mode.
  • Figure 7 is a graph of the spectral absorption (emission) rate of the coating material of Example 4 in the daytime heat collection mode and the night cooling mode.
  • Figure 8 is a graph of the spectral absorption (emission) rate of the coating material of Comparative Example 2 in the daytime heat collection mode and the night cooling mode.
  • the coating material of the present invention corresponds to different spectral characteristics during the day and night, and can change according to the temperature of the coating material , Change its own spectral characteristics to meet the requirements of high-efficiency solar heat collection during the day and radiant cooling at night.
  • T c is the transition temperature
  • T is the temperature of the coating material.
  • the temperature of the coating material is lower than the transition temperature, and the coating material is in radiant cooling mode.
  • the corresponding spectral characteristics are: solar radiation band (0.3 ⁇ 3 ⁇ m) and "atmospheric window” band (8 ⁇ 13 ⁇ m) high absorption (emission)
  • the coating material absorbs solar radiation and the temperature rises. When the temperature of the coating material is higher than the transition temperature, the coating material is at a high rate.
  • the other bands (3-8 ⁇ m and 13-25 ⁇ m) have low emission (absorption) rates.
  • the corresponding spectral characteristics are: solar radiation band (0.3 ⁇ 3 ⁇ m) high absorption (emission) rate, other bands (3 ⁇ 25 ⁇ m) low absorption (emission) rate.
  • a spectrally adaptive daytime solar heat collection and nighttime radiation refrigeration coating material includes a base layer 1, an infrared emitting layer 2, a phase change layer 3, and an anti-reflection layer 4 arranged in order from bottom to top.
  • the technical solution of the present invention mainly absorbs solar radiation through the structure of "anti-reflection layer 4, phase change layer 3", and arranges the base layer 1 on the lower surface of the infrared emitting layer 2, so that the solar radiation incident from the air passes through the "anti-reflection layer 4".
  • phase change layer 3 and the infrared emission layer 2" structure absorb.
  • the technical scheme of the present invention covers the upper surface of the infrared emitting layer 2 with the phase change layer 3: the infrared emitting layer 2 has a high emission (absorption) rate in the "atmospheric window” band (8-13 ⁇ m).
  • the phase change layer 3 has high absorptivity in the solar radiation waveband (0.3 ⁇ 3 ⁇ m), and at the same time, it has both "high temperature and low transmittance” and “low temperature and high transmittance” in the infrared waveband (3-25 ⁇ m) due to the thermally induced phase change characteristics.
  • the phase change layer 3 has a low transmittance in the infrared band (3-25 ⁇ m), and the infrared heat radiation emitted by the infrared emitting layer 2 is blocked, so the coating material is in the infrared band (3 ⁇ 25 ⁇ m) exhibits low emissivity and small radiant heat loss during daytime heat collection; at night, the temperature of the coating material is low, phase change layer 3 has high transmittance in the infrared band (3 ⁇ 25 ⁇ m), infrared emission The infrared heat radiation emitted by layer 2 can reach the upper atmosphere and outer space, and the coating material has a high emissivity in the atmospheric window band (8-13 ⁇ m), which realizes radiant cooling at night.
  • the technical solution of the present invention is to cover the upper surface of the phase change layer 3 with the anti-reflection layer 4, so that the reflectivity of the coating material to solar radiation (0.3 ⁇ 3 ⁇ m) is reduced, and the absorption (emission) rate is increased, which is beneficial to realize daytime High efficiency heat collection.
  • the material of the phase change layer generally has a high refractive index, and when light propagates from the air to the high refractive index material, greater reflection will occur at the interface.
  • the anti-reflection layer is generally a single layer of low refractive index material (material with a refractive index of less than or equal to 2 at a wavelength of 0.5 ⁇ m); or a low refractive index material (material with a refractive index of less than or equal to 2 at a wavelength of 0.5 ⁇ m) and a high refractive index material
  • High-efficiency materials materials with a refractive index of 2 at a wavelength of 0.5 ⁇ m
  • the alternate overlapping structure of the present invention is three layers, that is, "low refractive index material, high Refractive index materials, low refractive index materials”.
  • the infrared spectrum characteristics of the coating material can be automatically adjusted according to temperature changes. At night, the temperature of the coating material is lower than the phase transition temperature of vanadium dioxide. Vanadium dioxide is in an insulating state (M phase, monoclinic structure).
  • the M phase vanadium dioxide film has high transmittance in the infrared band (3-25 ⁇ m) ,
  • the infrared heat radiation emitted by the infrared emitting layer can pass through the phase change layer and the anti-reflection layer, so the coating material shows high emission (absorption) rate in the infrared band (especially the "atmospheric window” band (8-13 ⁇ m)), Realize radiant cooling at night; in the daytime, due to the absorption of solar radiation energy by the coating material, the temperature rises, when the temperature of the coating material is higher than the phase transition temperature of vanadium dioxide, vanadium dioxide transforms into a metallic state (R phase, tetragonal rutile structure) , R-phase vanadium dioxide film has high reflectivity in the infrared band, and the infrared heat radiation emitted by the infrared emission layer is shielded by the phase change layer. Therefore, the coating material exhibits low absorption (emission) rate in the infrared band, reducing
  • vanadium dioxide By using the visible-near infrared light absorption characteristics of vanadium dioxide, the complexity of the coating material structure is reduced.
  • vanadium dioxide is M phase, the forbidden band width is 0.67eV, and the wavelength of its intrinsic absorption limit is about 1.8 ⁇ m, which has relatively strong intrinsic absorption in the solar radiation band (0.3 ⁇ 3 ⁇ m); vanadium dioxide is R phase At this time, its free carrier absorption peak is around 0.6 ⁇ m, and it also has a high absorption (emission) rate in the solar radiation band. Therefore, in addition to regulating the infrared spectrum characteristics of the coating material, vanadium dioxide also enhances the absorption of the coating material in the solar radiation band.
  • the coating material can not add an additional solar radiation absorption structure, so that the coating material has a simple structure and is easy to prepare .
  • the absorption (emission) rate of the coating material in the solar radiation band (0.3-3 ⁇ m) can be further increased. After the solar radiation travels through the "anti-reflection layer, phase change layer, and infrared emission layer” structure, most of it will be absorbed, some will be reflected, and some will be transmitted.
  • a base layer is provided at the bottom of the infrared emitting layer. Part of the solar radiation that passes through will be absorbed by the base layer or absorbed by the upper "infrared emitting layer, phase change layer, anti-reflection layer” structure after being reflected by the base layer, which can effectively increase the coating.
  • the absorption (emission) rate of the layer material in the solar radiation band is provided at the bottom of the infrared emitting layer.
  • the anti-reflection layer is provided to reduce the reflectivity of the coating material in the solar radiation waveband (0.3-3 ⁇ m), thereby increasing the absorption (emission) rate in this waveband, which is conducive to achieving high-efficiency heat collection during the day.
  • the material of the phase change layer generally has a high refractive index, and when light propagates from the air to the high refractive index material, greater reflection will occur at the interface.
  • the anti-reflection layer is generally a single layer of low refractive index material; or a low refractive index material and a high refractive index material form a multilayer alternately overlapping structure. In order to make the coating structure simple and easier to process, the alternately overlapping structure is 3 layers , Namely "low refractive index material/high refractive index material/low refractive index material".
  • the daytime solar heat collection and nighttime radiant refrigeration coating material with self-adjusting thermal spectrum of the present invention can spontaneously change the temperature of the coating material according to the difference between daytime and nighttime solar radiation, thereby changing the coating material spectrum
  • the structure is relatively simple, easy to prepare, broadens the application fields of solar heat collection technology and radiant cooling technology, and has great promotion value.
  • a spectrally adaptive daytime solar heat collection and nighttime radiation refrigeration coating material includes a base layer 1, an infrared emitting layer 2, a phase change layer 3, and an anti-reflection layer 4 arranged in order from bottom to top.
  • the base layer 1 is 150 nm thick aluminum; the infrared emitting layer 2 is 500 ⁇ m thick quartz; the phase change layer 3 is 200 nm thick vanadium dioxide; the anti-reflection layer 4 is 86 nm thick aluminum oxide.
  • the spectral emission (absorption) rates of the 0.3-25 ⁇ m band in the daytime heat collection mode and the night radiant cooling mode are shown in Figure 3.
  • the absorption rate of the coating material in the solar radiation band (0.3 ⁇ 3 ⁇ m) is 0.85, and the emissivity in the infrared band (3 ⁇ 25 ⁇ m) is 0.25.
  • the solar irradiance is 900W/m 2
  • the ambient temperature is 30°C
  • the total heat transfer coefficient between the coating material and the environment is 5W/(m 2 K)
  • the heat collection temperature (coating material
  • the relationship between the temperature) and the heat collection efficiency (the ratio of the heat output by the coating material to the total solar radiation energy absorbed) is shown in the following table:
  • the coating material At night, when the temperature of the coating material is lower than the transition temperature, the coating material has an emissivity of 0.82 in the "atmospheric window" band (8-13 ⁇ m) and an absorption rate of 0.85 in the solar radiation band. Under such spectral characteristics, assuming that the ambient temperature is 30°C, the total heat transfer coefficient between the coating material and the environment is 5W/(m 2 K), the cooling temperature (the temperature of the coating material) and the cooling power density (coating per unit area) The cooling capacity output by the layer material) is shown in the following table:
  • the coating material structure in Example 1 when there is no phase change layer, the coating material structure is that the base layer 1 is 150 nm thick aluminum; the infrared emitting layer 2 is 500 ⁇ m thick quartz; the anti-reflection layer 4 is 86 nm thick Alumina. Since there is no phase change layer, the spectral characteristics of the coating material are fixed, as shown in Figure 4.
  • the coating material has an absorptivity of 0.13 in the solar radiation band (0.3 ⁇ 3 ⁇ m) and an emissivity of 0.8 in the infrared band (3 ⁇ 25 ⁇ m).
  • Example 2 Compared with Example 1, in Comparative Example 1, the absorption rate of the coating material in the solar radiation waveband is significantly reduced, indicating that the phase change layer 2 is the main solar radiation absorption layer.
  • a spectrally adaptive daytime solar heat collection and nighttime radiation refrigeration coating material includes a base layer 1, an infrared emitting layer 2, a phase change layer 3, and an anti-reflection layer 4 arranged in order from bottom to top.
  • the base layer 1 is 200nm thick tungsten; the infrared emitting layer 2 is 500 ⁇ m thick aluminum oxide single crystal (also called sapphire); the phase change layer 3 is 230nm thick vanadium dioxide; the anti-reflection layer 4 is made of 176nm thick silicon dioxide (Low refractive index material), 44nm thick vanadium dioxide (high refractive index material) and 92nm thick silicon dioxide (low refractive index material) are stacked in this order.
  • the spectral emission (absorption) rate of the 0.3-25 ⁇ m wavelength band in the daytime heat collection mode and the night radiant cooling mode is shown in Figure 5.
  • the absorption rate of the coating material in the solar radiation band (0.3 ⁇ 3 ⁇ m) is 0.9, and the emissivity in the infrared band (3 ⁇ 25 ⁇ m) is 0.3.
  • the solar irradiance is 900W/m 2
  • the ambient temperature is 30°C
  • the total heat transfer coefficient between the coating material and the environment is 5W/(m 2 K)
  • the heat collection temperature and efficiency are The relationship is shown in the following table:
  • the coating material At night, when the temperature of the coating material is lower than the transition temperature, the coating material has an emissivity of 0.7 in the "atmospheric window" band (8-13 ⁇ m) and an absorption rate of 0.83 in the solar radiation band. Under such spectral characteristics, assuming that the ambient temperature is 30°C, the total heat transfer coefficient between the coating material and the environment is 5W/(m 2 K), the cooling temperature and cooling power density are shown in the following table:
  • a spectrally adaptive daytime solar heat collection and nighttime radiation refrigeration coating material includes a base layer 1, an infrared emitting layer 2, a phase change layer 3, and an anti-reflection layer 4 arranged in order from bottom to top.
  • the base layer 1 is 200nm thick tungsten; the infrared emitting layer 2 is 500 ⁇ m thick aluminum oxide single crystal (also called sapphire); the phase change layer 3 is 230nm thick vanadium dioxide; the anti-reflection layer 4 is made of 150nm thick silicon dioxide (Low refractive index material), 35nm thick vanadium dioxide (high refractive index material), 261nm thick silicon dioxide (low refractive index material), 17nm thick vanadium dioxide (high refractive index material), 72nm thick two Silicon oxide (low-refractive index material) is sequentially stacked.
  • the spectral emission (absorption) rate of the 0.3-25 ⁇ m band in the daytime heat collection mode and the night radiant cooling mode is shown in Figure 6.
  • the absorption rate of the coating material in the solar radiation band (0.3 ⁇ 3 ⁇ m) is 0.91, and the emissivity in the infrared band (3 ⁇ 25 ⁇ m) is 0.32.
  • the solar irradiance is 900W/m 2
  • the ambient temperature is 30°C
  • the total heat transfer coefficient between the coating material and the environment is 5W/(m 2 K)
  • the heat collection temperature and efficiency are The relationship is shown in the following table:
  • the coating material At night, when the temperature of the coating material is lower than the transition temperature, the coating material has an emissivity of 0.7 in the "atmospheric window" band (8-13 ⁇ m) and an absorption rate of 0.84 in the solar radiation band. Under such spectral characteristics, assuming that the ambient temperature is 30°C, the total heat transfer coefficient between the coating material and the environment is 5W/(m 2 K), the cooling temperature and cooling power density are shown in the following table:
  • the structure of the anti-reflection layer in Example 2 is "low refractive index material/high refractive index material/low refractive index material” from bottom to top, while the structure of the anti-reflection layer in Example 3 is “low refractive index material” from bottom to top.
  • the absorption rate of the coating material in the solar radiation band can be enhanced by increasing the number of anti-reflection layers.
  • the anti-reflection layer is set as a single layer of low refractive index material or a three-layer structure of "low refractive index material/high refractive index material/low refractive index material".
  • a spectrally adaptive daytime solar heat collection and nighttime radiation refrigeration coating material includes a base layer 1, an infrared emitting layer 2, a phase change layer 3, and an anti-reflection layer 4 arranged in order from bottom to top.
  • the base layer 1 is a black chromium selective absorption coating; the infrared emission layer 2 is 1 mm thick glass; the phase change layer 3 is 160 nm thick vanadium dioxide; the anti-reflection layer 4 is 50 nm thick aluminum oxide.
  • the spectral emission (absorption) rate of the 0.3-25 ⁇ m wavelength band in the daytime heat collection mode and the night radiant cooling mode is shown in Figure 7.
  • the absorption rate of the coating material in the solar radiation band (0.3 ⁇ 3 ⁇ m) is 0.9, and the emissivity in the infrared band (3 ⁇ 25 ⁇ m) is 0.25.
  • the solar irradiance is 900W/m 2
  • the ambient temperature is 30°C
  • the total heat transfer coefficient between the coating material and the environment is 5W/(m 2 K)
  • the heat collection temperature and efficiency are The relationship is shown in the following table:
  • the coating material At night, when the temperature of the coating material is lower than the transition temperature, the coating material has an emissivity of 0.82 in the "atmospheric window" band (8-13 ⁇ m) and an absorption rate of 0.89 in the solar radiation band. Under such spectral characteristics, assuming that the ambient temperature is 30°C, the total heat transfer coefficient between the coating material and the environment is 5W/(m 2 K), the cooling temperature and cooling power density are shown in the following table:
  • the spectral characteristics of the material are similar to those of the prior art (CN103287014A).
  • the base layer 1 is a black chromium selective absorption coating;
  • the infrared emission layer 2 is 1 mm thick glass;
  • the anti-reflection layer 4 is 50 nm thick aluminum oxide. Since there is no phase change layer, the spectral characteristics of the coating material are fixed, as shown in Figure 8.
  • the absorption rate of the coating material in the solar radiation band (0.3 ⁇ 3 ⁇ m) is 0.89, and the emissivity in the infrared band (3 ⁇ 25 ⁇ m) is 0.8.
  • the solar irradiance is 900W/m 2
  • the ambient temperature is 30°C
  • the total heat transfer coefficient between the coating material and the environment is 5W/(m 2 K)
  • the heat collection temperature and efficiency are The relationship is shown in the following table:
  • Example 4 Compared with Example 4, when the heat collection temperature is 70°C and 85°C, the heat collection efficiency is significantly lower than that of Example 4. When the heat collection temperature is 100° C., the heat collection efficiency is less than 0, indicating that there is no heat collection capacity. At this time, the heat collection efficiency of Example 4 is 35%. Therefore, the existence of the phase change layer greatly improves the daytime heat collection efficiency of the coating material.
  • the coating material has an absorptivity of 0.89 in the solar radiation band (0.3 ⁇ 3 ⁇ m) and an emissivity of 0.8 in the "atmospheric window" band (8 ⁇ 13 ⁇ m).
  • the ambient temperature is 30°C
  • the total heat transfer coefficient between the coating material and the environment is 5W/(m 2 K)
  • the cooling temperature and cooling power density are shown in the following table:
  • Example 4 Compared with Example 4, the night radiant cooling performance is basically unchanged.
  • the daytime solar heat collection and nighttime radiation refrigeration coating material with self-adjustment and control of the thermo-induced spectrum of the present invention can spontaneously change the temperature of the coating material according to the difference of solar radiation during the day and night, and then change the spectral characteristics of the coating material to meet the requirements
  • the two functions of efficient solar heat collection and night radiant cooling, and the structure is relatively simple, easy to prepare, broaden the application field of solar heat collection technology and radiant cooling technology, and have great promotion value.

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Chemical & Material Sciences (AREA)
  • Sustainable Development (AREA)
  • Sustainable Energy (AREA)
  • Thermal Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Laminated Bodies (AREA)
  • Paints Or Removers (AREA)
  • Building Environments (AREA)

Abstract

本申请公开了一种光谱自适应的白天太阳能集热夜间辐射制冷涂层材料，其包括由下至上依次设置的基底层、红外发射层，相变层和减反射层；基底层为0.3～3μm的太阳辐射波段具有高吸收率的材料或0.3～3μm的太阳辐射波段具有高反射率的金属材料；红外发射层为8～13μm的"大气窗口"波段具有高发射率的材料；相变层为具有热致相变特性的材料；减反射层为单层低折射率材料或一种低折射率材料和一种高折射率材料构成交替重叠结构。本发明实现根据白天和夜间太阳辐射的差别，自发改变涂层材料温度，进而改变涂层材料光谱特性，满足白天高效率太阳能集热、夜间辐射制冷两种功能，具有极大的推广价值。

Description

一种光谱自适应的白天太阳能集热夜间辐射制冷涂层材料 技术领域
本发明属于能源利用技术领域，具体涉及光谱选择性可变的太阳能集热和辐射制冷综合应用，更具体地一种光谱自适应的白天太阳能集热夜间辐射制冷涂层材料。
背景技术
太阳是地球最大的热源和光源。太阳能利用主要有光电利用、光热利用和光化学利用几种形式。太阳能集热技术(光热利用)是太阳能利用最成熟的技术之一。太阳能集热技术的研究重点之一就是获得优质太阳能选择性吸收涂层材料，太阳能选择性吸收涂层材料在太阳辐射波段(0.3～3μm)具有高吸收(发射)率，在波长大于3μm的红外波段具有低吸收(发射)率。
地球大气层外宇宙空间温度接近绝对零度，是一个天然大冷源。地面上的物体可以通过“大气窗口”波段(这里指8～13μm)与宇宙空间进行辐射换热从而达到一定冷却效果，称为辐射制冷。理想辐射制冷涂层材料在“大气窗口”波段(8～13μm)具有高发射(吸收)率，在其他波段低发射(吸收)率。辐射制冷是一种被动式的、零能耗、零污染的制冷方式，对于建筑物降温节能和环境保护具有积极意义，近年来受到广泛的关注。
虽然太阳能集热技术已经很成熟，但受制于昼夜更替，太阳能集热器在夜间处于闲置状态；另一方面，夜间辐射制冷技术虽然比较成熟，但白天由于太阳辐射功率太大(数量级为10 3W/m 2，约为辐射制冷功率10倍)，白天辐射制冷很难实现，或者白天制冷功率很低。
太阳能集热技术和辐射制冷技术时间上可以互补，提升设备利用效率，但是由于光谱选择要求的冲突，现有的太阳能集热涂层材料不能实现辐射制冷效果，反之亦然。已有的关于太阳能集热和辐射制冷综合利用研究中，提出了理想白天太阳能集热-夜间辐射制冷涂层材料的光谱特性，即在太阳辐射波段(0.3～3μm)和“大气窗口”波段(8～13μm)具有高吸收(发射)率，其他波段(3～8μm和13～25μm)具有低吸收(发射)率。这样的涂层材料无论白天和夜间，光谱特性都一样，使得在白天太阳能集热模式下，由于涂层材料在“大气窗口”波段(8～13μm)具有高吸收(发射)率，有较大辐射热损，相比 传统太阳能选择性吸收涂层材料，热效率较低。
发明内容
为了增强白天太阳能集热夜间辐射制冷涂层材料的光谱选择性，解决白天太阳能集热和夜间辐射制冷光谱选择要求的冲突，提升涂层材料的白天集热效率。本发明提出了一种光谱自适应的白天太阳能集热夜间辐射制冷涂层材料。
一种光谱自适应的白天太阳能集热夜间辐射制冷涂层材料至少包括由下至上依次设置的基底层、红外发射层，相变层和减反射层；
所述基底层为对0.3～3μm的太阳辐射波段具有高吸收率(高吸收率指材料在0.3～3μm的太阳辐射波段的平均吸收率大于0.7)的材料或0.3～3μm的太阳辐射波段具有高反射率(高反射率指材料在0.3～3μm的太阳辐射波段的平均反射率大于0.7)的金属材料；
所述红外发射层为对8～13μm的“大气窗口”波段具有高发射率(高发射率指材料在8～13μm波段的平均发射率大于0.5)的材料；
所述相变层为具有热致相变特性的材料；
所述减反射层为单层低折射率材料或低折射率材料和高折射率材料构成多层交替重叠结构；
所述涂层材料在白天太阳能集热和夜间辐射制冷模式对应不同光谱选择性，且能根据涂层材料温度变化，通过热致相变原理，改变自身光谱选择性以满足白天高效率太阳能集热，夜间辐射制冷的光谱需求。所述涂层材料在白天吸收太阳辐射，温度升高，涂层材料的温度高于热致相变材料的相变温度时，涂层材料处于高效太阳能集热模式，涂层材料在0.3～3μm的太阳辐射波段的吸收率大于0.85，在3～25μm的红外波段发射率小于0.4；在夜间，涂层材料的温度低于热致相变材料的相变温度，涂层材料处于辐射制冷模式，涂层材料在8～13μm的“大气窗口”波段的发射率大于0.7，在0.3～3μm的太阳辐射波段的吸收率大于0.8。
进一步限定的技术方案如下：
所述太阳辐射波段(0.3～3μm)具有高吸收率材料为蓝钛、黑铬、黑漆中的一种。
所述0.3～3μm的太阳辐射波段具有高反射率的金属材料为铝、银、铜、钨、铬、钼、钛、镍或钴中的一种，厚度为100～500nm。
所述8～13μm波段具有高发射率的材料为玻璃、石英或氧化铝单晶中的一种。
所述具有热致相变特性的材料为二氧化钒，并且所述相变层的厚度为10～500nm，优 选80～300nm。
所述低折射率材料为0.5μm波长处折射率小于等于2的材料，并且所述减反射层的厚度为10～500nm，优选10～200nm。
所述低折射率材料的实例可以为二氧化硅或氧化铝中的一种。
所述高折射率材料为在0.5μm波长处折射率大于2的材料，所述高折射率材料的一个实例可以为二氧化钒。所述减反射层的厚度为10～500nm，优选10～200nm。
所述交替重叠结构由一层低折射率材料、一层高折射率材料和一层低折射率材料依次重叠构成。
附图说明
图1为一种光谱自适应的白天太阳能集热夜间辐射制冷涂层材料工作原理图；
图2为本发明的涂层材料结构示意图，且图中序号为：基底层1、红外发射层2、相变层3、减反射层4。
图3为实施例1涂层材料在白天集热模式和夜间制冷模式的光谱吸收(发射)率图。
图4为对比例1涂层材料在白天集热模式和夜间制冷模式的光谱吸收(发射)率图。
图5为实施例2涂层材料在白天集热模式和夜间制冷模式的光谱吸收(发射)率图。
图6为实施例3涂层材料在白天集热模式和夜间制冷模式的光谱吸收(发射)率图。
图7为实施例4涂层材料在白天集热模式和夜间制冷模式的光谱吸收(发射)率图。
图8为对比例2涂层材料在白天集热模式和夜间制冷模式的光谱吸收(发射)率图。
具体实施方式
下面结合附图和实施例对本发明作进一步说明。
参见图1，本发明一种光谱自适应的白天太阳能集热夜间辐射制冷涂层材料的工作原理如下：本发明的涂层材料在白天和夜间对应不同光谱特性，且能根据涂层材料温度变化，改变自身光谱特性以满足白天高效率太阳能集热，夜间辐射制冷的要求。图1中T c为转变温度，T为涂层材料温度。在夜间，涂层材料温度低于转变温度，涂层材料处于辐射制冷模式，对应的光谱特性为：太阳辐射波段(0.3～3μm)和“大气窗口”波段(8～13μm)高吸收(发射)率，其余波段(3～8μm和13～25μm)低发射(吸收)率；在白天，涂层材料吸收太阳辐射，温度升高，当涂层材料温度高于转变温度时，涂层材料处于高效率太阳能集热模式，对应的光谱特性为：太阳辐射波段(0.3～3μm)高吸收(发射)率，其 余波段(3～25μm)低吸收(发射)率。
参见图2，一种光谱自适应的白天太阳能集热夜间辐射制冷涂层材料包括由下至上依次设置的基底层1、红外发射层2、相变层3和减反射层4。本发明技术方案主要通过“减反射层4、相变层3”结构吸收太阳辐射，将基底层1设置在红外发射层2的下表面，使得从空气中入射的太阳辐射经“减反射层4、相变层3、红外发射层2”结构仍没被吸收的部分被基底层1吸收，或者由基底层1反射后被“红外发射层2、相变层3、减反射层4”结构所吸收。
本发明技术方案通过将相变层3覆盖在红外发射层2的上表面：红外发射层2在“大气窗口”波段(8～13μm)高发射(吸收)率。相变层3在太阳辐射波段(0.3～3μm)高吸收率的同时，在红外波段(3～25μm)由于热致相变特性具有“高温低透过率”和“低温高透过率”两种状态：在白天，涂层材料的温度高，相变层3在红外波段(3～25μm)有低透过率，红外发射层2发射的红外热辐射被阻挡，因而涂层材料在红外波段(3～25μm)表现出低发射率，白天集热时辐射热损小；在夜间，涂层材料的温度低，相变层3在红外波段(3～25μm)有高透过率，红外发射层2发射的红外热辐射能到达高层大气和外太空，涂层材料在大气窗口波段(8～13μm)的发射率高，实现夜间辐射制冷。
本发明技术方案通过将减反射层4覆盖在相变层3的上表面，使得涂层材料对太阳辐射(0.3～3μm)的反射率减小，吸收(发射)率增大，有利于实现白天高效率集热。相变层的材料一般具有高折射率，光由空气向高折射率材料传播时，在界面上会产生较大反射。减反射层一般为单层低折射率材料(0.5μm波长处折射率小于等于2的材料)；或者一种低折射率材料(0.5μm波长处折射率小于等于2的材料)和一种高折射率材料(0.5μm波长处折射率大2的材料)构成多层交替重叠结构，为了使涂层结构简单，更易于加工，本发明的交替重叠结构为3层，即“低折射率材料、高折射率材料、低折射率材料”。
本发明的有益技术效果体现在以下方面：
1.通过利用二氧化钒的热致相变特性，实现涂层材料的红外光谱特性根据温度变化自动调控。在夜间，涂层材料温度低于二氧化钒相变温度，二氧化钒为绝缘态(M相，单斜结构)，M相二氧化钒薄膜在红外波段(3～25μm)具有高透过率，红外发射层发射出的红外热辐射能透过相变层和减反射层，因此涂层材料表现出红外波段(尤其是“大气窗口”波段(8～13μm))高发射(吸收)率，实现夜间辐射制冷；在白天，由于涂层材料吸收太阳辐射能量，温度升高，涂层材料温度高于二氧化钒相变温度时，二氧化钒转变为金属态(R相，四方金红石结构)，R相二氧化钒薄膜在红外波段具有高反射率，红外发射层发 射出的红外热辐射被相变层屏蔽，因此涂层材料在红外波段表现出低吸收(发射)率，降低白天太阳能集热时的辐射热损。
2.通过利用二氧化钒对可见-近红外光的吸收特性，降低涂层材料结构复杂程度。二氧化钒为M相时，禁带宽度为0.67eV，其本征吸收限的波长约为1.8μm，在太阳辐射波段(0.3～3μm)具有比较强的本征吸收；二氧化钒为R相时，其自由载流子吸收峰在0.6μm左右，在太阳辐射波段也具有高吸收(发射)率。因此，二氧化钒除了对涂层材料红外光谱特性进行调控外还增强涂层材料对太阳辐射波段的吸收，涂层材料可以不增加额外太阳辐射吸收结构，从而使涂层材料结构简单，易于制备。
3.通过设置基底层，能进一步增加涂层材料在太阳辐射波段(0.3～3μm)吸收(发射)率。太阳辐射传播经过“减反射层、相变层、红外发射层”结构后，大部分会被吸收、一部分会被反射、一部分会透过。在红外发射层底部设置基底层，透过部分的太阳辐射会被基底层吸收，或者被基底层反射后由上部“红外发射层、相变层、减反射层”结构吸收，因而能有效增加涂层材料在太阳辐射波段吸收(发射)率。
4.通过设置减反射层，降低涂层材料在太阳辐射波段(0.3～3μm)的反射率，从而增加在此波段的吸收(发射)率，有利于实现白天高效率集热。相变层的材料一般具有高折射率，光由空气向高折射率材料传播时，在界面上会产生较大反射。减反射层一般为单层低折射率材料；或者一种低折射率材料和一种高折射率材料构成多层交替重叠结构，为了使涂层结构简单，更易于加工，交替重叠结构为3层，即“低折射率材料/高折射率材料/低折射率材料”。
综上所述，本发明所述的热致光谱自适应调控的白天太阳能集热夜间辐射制冷涂层材料能根据白天和夜间太阳辐射的差别，自发改变涂层材料温度，进而改变涂层材料光谱特性，满足白天高效率太阳能集热、夜间辐射制冷两种功能，且结构较为简单，易于制备，拓宽了太阳能集热技术和辐射制冷技术的应用领域，具有极大的推广价值。
实施例
实施例1
参见图2，一种光谱自适应的白天太阳能集热夜间辐射制冷涂层材料包括由下至上依次设置的基底层1、红外发射层2、相变层3和减反射层4。
基底层1为150nm厚的铝；红外发射层2为500μm厚的石英；相变层3为200nm厚的二氧化钒；减反射层4为86nm厚的氧化铝。其白天集热模式和夜间辐射制冷模式0.3～25 μm波段的光谱发射(吸收)率如图3所示。
在白天，涂层材料的温度高于转变温度时，涂层材料在太阳辐射波段(0.3～3μm)的吸收率为0.85，在红外波段(3～25μm)发射率为0.25。在这样的光谱特征下，假设太阳辐照度为900W/m 2，环境温度为30℃，涂层材料与环境的总传热系数为5W/(m 2K)，集热温度(涂层材料的温度)和集热效率(涂层材料能输出的热量占所吸收总太阳辐射能量的比例)的关系如下表所示：
集热温度(℃) 70 85 100
集热效率 55％ 43％ 32％
在夜间，涂层材料的温度低于转变温度时，涂层材料在“大气窗口”波段(8～13μm)发射率为0.82，在太阳辐射波段吸收率为0.85。在这样的光谱特征下，假设环境温度为30℃，涂层材料与环境的总传热系数为5W/(m 2K)，制冷温度(涂层材料的温度)和制冷功率密度(单位面积涂层材料输出的冷量功率)如下表所示：
制冷温度(℃) 20 25 30
制冷功率密度(W/m 2) 26 72 119
对比例1
对于实施例1中的涂层材料结构，当没有相变层时，涂层材料结构为基底层1为150nm厚的铝；红外发射层2为500μm厚的石英；减反射层4为86nm厚的氧化铝。由于没有相变层，涂层材料的光谱特性固定不变，如图4所示。
涂层材料在太阳辐射波段(0.3～3μm)的吸收率为0.13，在红外波段(3～25μm)发射率为0.8。
与实施例1相比，对比例1中涂层材料在太阳辐射波段的吸收率显著减小，说明相变层2是太阳辐射的主要吸收层。
实施例2
参见图2，一种光谱自适应的白天太阳能集热夜间辐射制冷涂层材料包括由下至上依次设置的基底层1、红外发射层2、相变层3和减反射层4。
基底层1为200nm厚的钨；红外发射层2为500μm厚的氧化铝单晶(又称蓝宝石)；相变层3为230nm厚的二氧化钒；减反射层4由176nm厚的二氧化硅(低折射率材料)、 44nm厚的二氧化钒(高折射率材料)和92nm厚的二氧化硅(低折射率材料)依次重叠构成。其白天集热模式和夜间辐射制冷模式0.3～25μm波段的光谱发射(吸收)率如图5所示。
在白天，涂层材料的温度高于转变温度时，涂层材料在太阳辐射波段(0.3～3μm)的吸收率为0.9，在红外波段(3～25μm)发射率为0.3。在这样的光谱特征下，假设太阳辐照度为900W/m 2，环境温度为30℃，涂层材料与环境的总传热系数为5W/(m 2K)，集热温度和集热效率的关系如下表所示：
集热温度(℃) 70 85 100
集热效率 55％ 42％ 29％
在夜间，涂层材料的温度低于转变温度时，涂层材料在“大气窗口”波段(8～13μm)发射率为0.7，在太阳辐射波段吸收率为0.83。在这样的光谱特征下，假设环境温度为30℃，涂层材料与环境的总传热系数为5W/(m 2K)，制冷温度和制冷功率密度如下表所示：
制冷温度(℃) 20 25 30
制冷功率密度(W/m 2) 10 50 91
实施例3
参见图2，一种光谱自适应的白天太阳能集热夜间辐射制冷涂层材料包括由下至上依次设置的基底层1、红外发射层2、相变层3和减反射层4。
基底层1为200nm厚的钨；红外发射层2为500μm厚的氧化铝单晶(又称蓝宝石)；相变层3为230nm厚的二氧化钒；减反射层4由150nm厚的二氧化硅(低折射率材料)、35nm厚的二氧化钒(高折射率材料)，261nm厚的二氧化硅(低折射率材料)，17nm厚的二氧化钒(高折射率材料)，72nm厚的二氧化硅(低折射率材料)依次重叠构成。其白天集热模式和夜间辐射制冷模式0.3～25μm波段的光谱发射(吸收)率如图6所示。
在白天，涂层材料的温度高于转变温度时，涂层材料在太阳辐射波段(0.3～3μm)的吸收率为0.91，在红外波段(3～25μm)发射率为0.32。在这样的光谱特征下，假设太阳辐照度为900W/m 2，环境温度为30℃，涂层材料与环境的总传热系数为5W/(m 2K)，集热温度和集热效率的关系如下表所示：
集热温度(℃) 70 85 100
集热效率 51％ 36％ 21％
在夜间，涂层材料的温度低于转变温度时，涂层材料在“大气窗口”波段(8～13μm)发射率为0.7，在太阳辐射波段吸收率为0.84。在这样的光谱特征下，假设环境温度为30℃，涂层材料与环境的总传热系数为5W/(m 2K)，制冷温度和制冷功率密度如下表所示：
制冷温度(℃) 20 25 30
制冷功率密度(W/m 2) 9 49 90
可以看出，实施例2中减反射层结构由下至上为“低折射率材料/高折射率材料/低折射率材料”，而实施例3中减反射层结构由下至上为“低折射率材料/高折射率材料/低折射率材料/高折射率材料/低折射率材料”。实施例2中，涂层材料的温度高于转变温度时，涂层材料在太阳辐射波段(0.3～3μm)的吸收率为0.9；实施例3中，涂层材料的温度高于转变温度时，涂层材料在太阳辐射波段(0.3～3μm)的吸收率为0.91。因此，可以通过增加减反射层的层数来增强涂层材料在太阳辐射波段的吸收率。但是为了使涂层结构简单，更易于加工，减反射层设置为单层低折射率材料或者“低折射率材料/高折射率材料/低折射率材料”的三层结构。
实施例4
参见图2，一种光谱自适应的白天太阳能集热夜间辐射制冷涂层材料包括由下至上依次设置的基底层1、红外发射层2、相变层3和减反射层4。
基底层1为黑铬选择性吸收涂层；红外发射层2为1mm厚的玻璃；相变层3为160nm厚的二氧化钒；减反射层4为50nm厚的氧化铝。其白天集热模式和夜间辐射制冷模式0.3～25μm波段的光谱发射(吸收)率如图7所示。
在白天，涂层材料的温度高于转变温度时，涂层材料在太阳辐射波段(0.3～3μm)的吸收率为0.9，在红外波段(3～25μm)发射率为0.25。在这样的光谱特征下，假设太阳辐照度为900W/m 2，环境温度为30℃，涂层材料与环境的总传热系数为5W/(m 2K)，集热温度和集热效率的关系如下表所示：
集热温度(℃) 70 85 100
集热效率 58％ 47％ 35％
在夜间，涂层材料的温度低于转变温度时，涂层材料在“大气窗口”波段(8～13μm)发射率为0.82，在太阳辐射波段吸收率为0.89。在这样的光谱特征下，假设环境温度为30℃，涂层材料与环境的总传热系数为5W/(m 2K)，制冷温度和制冷功率密度如下表所示：
制冷温度(℃) 20 25 30
制冷功率密度(W/m 2) 25 72 120
对比例2
对于实施例4中的涂层材料结构，当没有相变层时，材料的光谱特性和现有技术(CN103287014A)相似。基底层1为黑铬选择性吸收涂层；红外发射层2为1mm厚的玻璃；减反射层4为50nm厚的氧化铝。由于没有相变层，涂层材料的光谱特性固定不变，如图8所示。
在白天，涂层材料在太阳辐射波段(0.3～3μm)的吸收率为0.89，在红外波段(3～25μm)发射率为0.8。在这样的光谱特征下，假设太阳辐照度为900W/m 2，环境温度为30℃，涂层材料与环境的总传热系数为5W/(m 2K)，集热温度和集热效率的关系如下表所示：
集热温度(℃) 70 85 100
集热效率 28％ 6％ -17％
与实施例4相比，当集热温度为70℃和85℃时，集热效率显著小于实施例4。当集热温度为100℃时，集热效率小于0，说明没有集热能力，而此时实施例4的集热效率为35％。因此，相变层的存在，大大提高了涂层材料白天集热效率。
在夜间，涂层材料在太阳辐射波段(0.3～3μm)的吸收率为0.89，在在“大气窗口”波段(8～13μm)发射率为0.8。在这样的光谱特征下，假设环境温度为30℃，涂层材料与环境的总传热系数为5W/(m 2K)，制冷温度和制冷功率密度如下表所示：
制冷温度(℃) 20 25 30
制冷功率密度(W/m 2) 19 66 115
与实施例4相比，夜间辐射制冷性能基本没有改变。
工业可适用性
本发明所述的热致光谱自适应调控的白天太阳能集热夜间辐射制冷涂层材料能根据白天和夜间太阳辐射的差别，自发改变涂层材料温度，进而改变涂层材料光谱特性，满足白天高效率太阳能集热、夜间辐射制冷两种功能，且结构较为简单，易于制备，拓宽了太阳能集热技术和辐射制冷技术的应用领域，具有极大的推广价值。

Claims (10)

  1. 一种光谱自适应的白天太阳能集热夜间辐射制冷涂层材料，其中所述涂层材料至少包括由下至上依次设置的基底层、红外发射层、相变层和减反射层；
    所述基底层为在0.3～3μm的太阳辐射波段具有高吸收率的材料或在0.3～3μm的太阳辐射波段具有高反射率的金属材料；
    所述红外发射层为在8～13μm的“大气窗口”波段具有高发射率的材料；
    所述相变层为具有热致相变特性的材料；
    所述减反射层为单层低折射率材料或由低折射率材料和高折射率材料构成的交替重叠结构；
    在白天，所述涂层材料吸收太阳辐射，温度升高，处于高效太阳能集热模式，在0.3～3μm的太阳辐射波段的吸收率大于0.8，在3～25μm的红外波段发射率小于0.4；在夜间，所述涂层材料处于辐射制冷模式，在8～13μm的“大气窗口”波段的发射率大于0.7，在0.3～3μm的太阳辐射波段的吸收率大于0.8。
  2. 根据权利要求1所述的光谱自适应的白天太阳能集热夜间辐射制冷涂层材料，其中所述在0.3～3μm的太阳辐射波段具有高吸收率材料为蓝钛、黑铬或黑漆中的一种。
  3. 根据权利要求1所述的光谱自适应的白天太阳能集热夜间辐射制冷涂层材料，其中所述在0.3～3μm的太阳辐射波段具有高反射率的金属材料为铝、银、铜、钨、铬、钼、钛、镍或钴中的一种，厚度为100～500nm。
  4. 根据权利要求1所述的光谱自适应的白天太阳能集热夜间辐射制冷涂层材料，其中在所述8～13μm的“大气窗口”波段具有高发射率的材料为玻璃、石英或氧化铝单晶中的一种。
  5. 根据权利要求1所述的光谱自适应的白天太阳能集热夜间辐射制冷涂层材料，其中所述具有热致相变特性的材料为二氧化钒，并且所述相变层的厚度为10～500nm。
  6. 根据权利要求1所述的光谱自适应的白天太阳能集热夜间辐射制冷涂层材料，其中所述低折射率材料为在0.5μm波长处折射率小于等于2的材料，并且所述减反射层的厚度为10～500nm。
  7. 根据权利要求6所述的光谱自适应的白天太阳能集热夜间辐射制冷涂层材料，其中所述低折射率材料为二氧化硅和氧化铝中的一种。
  8. 根据权利要求1所述的光谱自适应的白天太阳能集热夜间辐射制冷涂层材料，其中 所述高折射率材料为在0.5μm波长处折射率大于2的材料，并且所述减反射层的厚度为10～500nm。
  9. 根据权利要求1所述的一种光谱自适应的白天太阳能集热夜间辐射制冷涂层材料，其中所述交替重叠结构由一层低折射率材料、一层高折射率材料和一层低折射率材料依次重叠构成。
  10. 根据权利要求1所述的光谱自适应的白天太阳能集热夜间辐射制冷涂层材料，其中所述高折射率材料为二氧化钒。
PCT/CN2020/083722 2019-04-09 2020-04-08 一种光谱自适应的白天太阳能集热夜间辐射制冷涂层材料 WO2020207407A1 (zh)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN201910279554.2A CN110030744B (zh) 2019-04-09 2019-04-09 一种光谱自适应的白天太阳能集热夜间辐射制冷涂层材料
CN201910279554.2 2019-04-09

Publications (1)

Publication Number Publication Date
WO2020207407A1 true WO2020207407A1 (zh) 2020-10-15

Family

ID=67237737

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2020/083722 WO2020207407A1 (zh) 2019-04-09 2020-04-08 一种光谱自适应的白天太阳能集热夜间辐射制冷涂层材料

Country Status (2)

Country Link
CN (1) CN110030744B (zh)
WO (1) WO2020207407A1 (zh)

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110030744B (zh) * 2019-04-09 2020-06-26 中国科学技术大学 一种光谱自适应的白天太阳能集热夜间辐射制冷涂层材料
CN112984836A (zh) * 2019-12-17 2021-06-18 南京工业大学 一种被动式冷热双效材料
CN112993583B (zh) * 2021-01-31 2023-03-10 郑州大学 一种实现可调谐超宽带的二氧化钒超材料结构及其应用
CN114543373B (zh) * 2022-03-07 2022-10-28 中国科学技术大学 一种基于太阳热辐射和太空冷辐射的光谱调控器件
CN115572939A (zh) * 2022-11-01 2023-01-06 中建中环新能源有限公司 基于仿生银蚁毛发微纳结构的透明辐射制冷薄膜及其制备方法与应用

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103287014A (zh) * 2013-06-27 2013-09-11 裴刚 满足太阳能集热和辐射制冷的选择性吸收发射复合材料
CN204138748U (zh) * 2014-04-03 2015-02-04 周少波 相变型二氧化钒薄膜结构
CN110030744A (zh) * 2019-04-09 2019-07-19 中国科学技术大学 一种光谱自适应的白天太阳能集热夜间辐射制冷涂层材料

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN205174878U (zh) * 2015-11-03 2016-04-20 广东五星太阳能股份有限公司 具有白天集热和夜间辐射制冷功能的复合抛物面聚光集散热器
CN205070939U (zh) * 2015-11-03 2016-03-02 广东五星太阳能股份有限公司 具有夜间辐射制冷功能的平板型光伏光热综合利用装置
CN107219581A (zh) * 2016-03-21 2017-09-29 张家港康得新光电材料有限公司 智能温控膜与其的应用
WO2018180177A1 (ja) * 2017-03-28 2018-10-04 大阪瓦斯株式会社 放射冷却装置および放射冷却方法

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103287014A (zh) * 2013-06-27 2013-09-11 裴刚 满足太阳能集热和辐射制冷的选择性吸收发射复合材料
CN204138748U (zh) * 2014-04-03 2015-02-04 周少波 相变型二氧化钒薄膜结构
CN110030744A (zh) * 2019-04-09 2019-07-19 中国科学技术大学 一种光谱自适应的白天太阳能集热夜间辐射制冷涂层材料

Also Published As

Publication number Publication date
CN110030744B (zh) 2020-06-26
CN110030744A (zh) 2019-07-19

Similar Documents

Publication Publication Date Title
WO2020207407A1 (zh) 一种光谱自适应的白天太阳能集热夜间辐射制冷涂层材料
US11914179B2 (en) Radiative cooling optical filter, its preparing method and application
JP3577034B2 (ja) 複合材料
JP4565105B2 (ja) 太陽電池用の光学薄膜およびその製造方法
CN105393065B (zh) 一种吸收材料以及使用这种材料的太阳能板
US11951710B2 (en) Radiative cooling device
CN112921273B (zh) 一种基于相变材料二氧化钒的动态热辐射制冷器件
CN110041735B (zh) 一种光谱选择性白天辐射制冷涂层材料
CN112993583B (zh) 一种实现可调谐超宽带的二氧化钒超材料结构及其应用
CN112984857A (zh) 一种具有结构色的辐射制冷多层膜结构
US20230402971A1 (en) Split band-based reversely different light path solar thermal compound device
KR101417957B1 (ko) 써모크로믹 윈도우 및 이의 제조방법
CN214469444U (zh) 一种基于相变材料的辐射制冷薄膜
CN104596138B (zh) 一种太阳能选择性吸收膜系
CN203673095U (zh) 一种用于微型热光电系统的光子晶体过滤器
US20170153045A1 (en) Solar absorption structure
CN115011936B (zh) 基于周期性损耗介质的选择性分光吸热涂层及其制备方法
CN106091443A (zh) 一种选择性太阳能吸收涂层
CN107104162B (zh) 一种选择性红外辐射器
CN209836290U (zh) 一种三维锥形纳米层膜结构
CN111609573B (zh) 利用多重光子异质结构界面的太阳能选择性吸收材料
CN114576873A (zh) 一种彩色太阳能光热转换元件
CN113257925A (zh) 一种利用红外增透散热的硅太阳能电池片
CN215676611U (zh) 一种基于相变材料的自适应调节膜及节能窗
CN211879397U (zh) 一种高光转换效率高散热的高功率双玻组件

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 20788547

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 20788547

Country of ref document: EP

Kind code of ref document: A1

122 Ep: pct application non-entry in european phase

Ref document number: 20788547

Country of ref document: EP

Kind code of ref document: A1

32PN Ep: public notification in the ep bulletin as address of the adressee cannot be established

Free format text: NOTING OF LOSS OF RIGHTS PURSUANT TO RULE 112(1) EPC (EPO FORM 1205A DATED 14.04.2022)