A multilayer film structure for radiative cooling with structural color

Abstract

The present invention provides a radiative cooling multilayer film structure capable of presenting structural colors. It includes a top radiative cooling device structure and a bottom color former structure, and the color former structure includes a MIM structure and a two-period one-dimensional quasi-photonic crystal structure stacked from bottom to top. The total thickness of the multilayer film structure is 1.657μm to 1.87μm, and quartz glass or Si is used as the substrate material. The structure has a strong reflection ability in the solar light band, and the reflectivity in most solar light bands reaches above 0.9. The multilayer film structure of the present invention can overcome the problem that the current radiative cooling structure is limited in application occasions due to the single color. And compared with the radiative cooling metasurface photonic device that can present structural colors, the one-dimensional structural color radiative cooling multilayer film has the huge advantages of low manufacturing cost and simple process. The radiative cooling multilayer film structure presenting structural colors has broad application prospects in the fields of outdoor objects and thermal management of electronic products.

Description

Technical Field

[0001] The invention relates to the field of spectrally selective micro-nano structures, and in particular to a radiation cooling multilayer film structure with structural color. Background Art

[0002] With the development of modern society, human consumption and demand for energy are increasing day by day. At present, the energy problem has evolved into a global problem. At the same time, due to the increasing climate problems such as global warming and greenhouse effect, the global demand for refrigeration is rising. Active refrigeration equipment, such as air conditioners and fans, inevitably consume a lot of energy in the refrigeration process. Selective radiation cooling is a passive refrigeration technology that covers the object with a structure with selective high emissivity in the atmospheric window (8-13μm) to achieve radiation heat exchange between the object and the low-temperature outer space, thereby cooling the object. As a spontaneous refrigeration technology that does not require any energy consumption, this technology has broad development and application prospects. It can be applied to building energy saving, electronic device heat dissipation, outdoor object surface thermal management, photovoltaic cell cooling and other fields. At present, radiation cooling is divided into daytime radiation cooling and nighttime radiation cooling. Compared with nighttime radiation cooling, daytime radiation cooling also needs to consider the absorption of solar radiation energy, so it is more difficult to achieve. Daytime radiation cooling technology requires not only that the object has high emissivity in the atmospheric window band of 8 to 13 μm, but also that it has high reflectivity in the sunlight band of 0.3 to 4 μm to reduce the absorption of solar radiation energy and ensure the cooling effect. However, due to the performance requirements of high reflectivity in the sunlight band, almost all daytime radiation cooling structures are currently white or silver in color, and the monotony of the color greatly limits its application space. In the field of micro-nano photonic devices, some scholars have used a multilayer film structure combining a metal-dielectric-metal (MIM) structure and a one-dimensional radiation refrigerator to simultaneously achieve radiation cooling and structural color presentation. However, due to the limitations of the single absorption peak characteristics of the MIM structure, the colors that can be presented are still very limited, and the additive three primary colors of red-green-blue (RGB) structural colors cannot be presented. Other scholars have used metasurface radiation cooling photonic devices to simultaneously achieve radiation cooling and present structural colors, but this structure has the problem of high processing difficulty. Summary of the invention

[0003] In view of the defects in the prior art, an object of the present invention is to provide a radiant cooling multilayer film structure with structural color.

[0004] According to the present invention, a radiative cooling multilayer film structure with structural color includes a one-dimensional multilayer film structure, wherein the one-dimensional multilayer film structure includes a top radiative cooler structure and a bottom color former structure, and the color former structure includes a MIM structure stacked from bottom to top and a two-period one-dimensional quasi-photonic crystal structure.

[0005] Preferably, the total thickness of the one-dimensional multilayer film structure is 1.657 μm to 1.87 μm.

[0006] Preferably, the metal layer material of the MIM structure is one of Ag, Au or Al, and the dielectric layer material is one of SiO2, Al2O3, TiO2, HfO2, Si3N4.

[0007] Preferably, the two-period one-dimensional quasi-photonic crystal structure is composed of two dielectric films with different refractive indices stacked alternately, wherein the low refractive index material is one of SiO2, MgF2, and CaF2, and the high refractive index material is one of TiO2, HfO2, and SiC.

[0008] Preferably, the two-period one-dimensional quasi-photonic crystal structure cooperates with the top metal layer of the MIM structure.

[0009] Preferably, the radiation cooler structure is composed of one or more materials selected from SiO2, Si3N4, and Al2O3.

[0010] Preferably, Ag is used as the metal layer material of the MIM structure, and SiO2 is used as the dielectric layer material of the MIM structure;

[0011] The thickness of the bottom Ag layer ranges from 40 to 100 nm, the thickness of the top Ag layer ranges from 10 to 80 nm, and the thickness of the SiO2 layer ranges from 90 to 170 nm;

[0012] SiO2 and TiO2 are used as materials for the two-period one-dimensional quasi-photonic crystal, the thickness of the SiO2 layer is in the range of 50 to 100 nm, and the thickness of the TiO2 layer is in the range of 20 to 60 nm;

[0013] SiO2 and Si3N4 are used as the materials of the radiation cooler. The thickness of the Si3N4 layer is set to 900nm, and the thickness of the SiO2 layer is 325nm-425nm.

[0014] Preferably, the one-dimensional multilayer film structure presents structural colors of subtractive three primary colors and additive three primary colors, which are light purple, light cyan and light yellow; light red, light green and light blue;

[0015] The color coordinates (x, y, Y) of the one-dimensional multilayer film structure in the CIE 1931 chromaticity diagram are light purple (0.31, 0.30, 85.30), light cyan (0.30, 0.33, 95.93) and light yellow (0.33, 0.36, 97.15); light red (0.35, 0.35, 84.24), light green (0.33, 0.37, 94.12) and light blue (0.29, 0.32, 84.02).

[0016] Preferably, the theoretical net radiative cooling power of the radiative cooling multilayer film presenting subtractive three primary color structural colors is 75.46 W / m 2 ~84.56W / m 2 , achieving a 10.9℃~12℃ reduction compared to the ambient temperature of 30℃;

[0017] The theoretical net radiative cooling power of the radiative cooling composite coating with additive three-primary color structural color is 19.39W / m 2 ~43.56W / m 2 , achieving a 2.6℃~6℃ reduction compared to the ambient temperature of 30℃.

[0018] Preferably, the one-dimensional multilayer film structure uses quartz glass or silicon as a base material.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] 1. The radiative cooling multilayer film structure with structural colors described in the present invention realizes that the structure presents structural colors through spectral absorption peaks while ensuring the radiative cooling effect through the narrow-band reflection valley presented by the color former structure in a specific band of visible light and the broadband high reflection characteristics in other bands of sunlight and the high emission characteristics of the radiative cooler in the atmospheric window band.

[0021] 2. Compared with the current conventional radiation cooling structure, the radiation cooling multilayer film described in the present invention can present a variety of colors, which solves the problem of limited application space due to the single color of the existing conventional radiation cooling structure, and at the same time solves the problem that the existing structural color radiation cooling micro-nano photonic devices are limited in color or difficult to process.

[0022] 3. Compared with the pigment coloring radiation cooling structure, the radiation cooling multilayer film is colored by structural color, and has the great advantages of high coloring stability, strong corrosion resistance, and never fading in various environments.

[0023] 4. Compared with the existing structural color radiation cooling photonic devices, the radiation cooling multilayer film has the great advantages of presenting a wide range of colors, simple processing and low cost.

[0024] 5. Compared with the existing one-dimensional radiation cooling multilayer film structure that can present structural colors, the present invention has the advantage of being able to present RGB additive three-primary color structural colors. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Other features, objects and advantages of the present invention will become more apparent from the detailed description of non-limiting embodiments made with reference to the following drawings:

[0026] Figure 1It is a schematic diagram of the structure of the radiative cooling multilayer film with structural color according to the present invention.

[0027] Figure 2 It is the emissivity curve diagram of the preferred radiation cooling multilayer film structure presenting subtractive three primary colors in the full band (0.3-24 μm).

[0028] Figure 3 It is the emissivity curve diagram of the preferred radiation cooling multilayer film structure presenting additive three primary colors in the full band (0.3-24 μm).

[0029] Figure 4 It is a color coordinate diagram of the subtractive three-primary color structural colors presented by the preferred radiative cooling multilayer film and the corresponding structural colors in the CIE 1931 chromaticity space.

[0030] Figure 5 It is a color coordinate diagram of the additive three primary colors structural colors presented by the preferred radiative cooling multilayer film and the corresponding structural colors in the CIE 1931 chromaticity space.

[0031] Figure 6 It is a theoretical daytime radiation cooling power curve diagram of the preferred radiation cooling multilayer film presenting subtractive three primary colors.

[0032] Figure 7 It is a theoretical daytime radiation cooling power curve diagram of the preferred radiation cooling multilayer film presenting additive three primary colors.

[0033] Figure 8 It is a diagram of various colors that the radiative cooling multilayer film can present and the corresponding net radiative cooling power. DETAILED DESCRIPTION

[0034] The present invention is described in detail below in conjunction with specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, for those of ordinary skill in the art, several changes and improvements can also be made without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

[0035] like Figures 1 to 8 As shown, a radiative cooling multilayer film structure with structural color provided by the present invention is composed of a color former with a total thickness of 1.657 μm to 1.87 μm and a radiative cooling structure. The bottom color former is composed of a MIM structure and a two-period one-dimensional quasi-photonic crystal structure stacked together, with the two-period one-dimensional quasi-photonic crystal structure on top and the MIM structure on the bottom.

[0036] The metal layer material of the MIM structure is one of Ag, Au or Al, and the dielectric layer material is one of SiO2, Al2O3, TiO2, HfO2, and Si3N4. The nanoscale MIM structure can excite a resonance mode in a specific band of visible light, thereby generating a narrow-band absorption peak. The band of the resonant narrow-band absorption generated by the MIM structure can be directly controlled by changing the thickness of the middle SiO2 layer.

[0037] The two-period one-dimensional quasi-photonic crystal structure is composed of two dielectric materials with high and low refractive indices, where the low refractive index material is one of SiO2, MgF2, and CaF2, and the high refractive index material is one of TiO2, HfO2, and SiC. In the color former, the two-period one-dimensional quasi-photonic crystal structure can cooperate with the top metal in the MIM structure to excite the resonance mode in the dielectric layer above the metal, thereby generating a reflection valley. Furthermore, the wavelength band of the resonance mode can be directly controlled by changing the thickness of each layer of the two-period one-dimensional quasi-photonic crystal.

[0038] The bottom color former can excite resonance modes in the dielectric materials on both sides of the middle metal layer in the visible light band, thereby forming a reflection valley to present structural colors. Furthermore, the band, peak size and number of the reflection valley can be adjusted by changing the thickness of the dielectric layer in the MIM structure, the thickness of each layer of the two-period one-dimensional quasi-photonic crystal or the thickness of the middle metal layer, thereby presenting a variety of structural colors.

[0039] Furthermore, Ag, a metal material with good reflection ability for sunlight (0.3-4 μm), is selected as the metal layer material of the MIM structure, and SiO2, which has high emission characteristics in the atmospheric window, is selected as the dielectric layer material of the MIM structure. The thickness of the bottom Ag layer ranges from 40 to 100 nm, and the thickness of the top Ag layer ranges from 10 to 80 nm. The thickness of the SiO2 layer ranges from 90 to 170 nm. SiO2 and TiO2, which have emission characteristics in the atmospheric window, are selected as the materials of the two-period one-dimensional quasi-photonic crystal. The thickness of the SiO2 layer ranges from 50 to 100 nm, and the thickness of the TiO2 layer ranges from 20 to 60 nm.

[0040] Ag, SiO2 and TiO2 are selected as materials for the color former structure, and one or more of SiO2, Si3N4 and Al2O3 are selected as materials for the radiation cooler. The thickness of each layer of the film is optimized based on the electromagnetic wave theory design according to the specific color former structure size, and the optimal layer thickness parameters with the highest average emissivity in the 8-13μm atmospheric window band are calculated and designed using electromagnetic wave theory. SiO2 and Si3N4 materials are preferably selected as radiation cooler materials, with the SiO2 layer on the top and the Si3N4 layer on the bottom. The thickness of the Si3N4 layer is set to 900nm, and for the multilayer film that presents additive (RGB) / subtractive (CMY) primary color structural colors, the optimized SiO2 layer thickness is 325nm~425nm. The preferred radiation cooling multilayer film structure has an overall reflectivity of 89.38% to 95.46% in the sunlight band (0.3 to 4 μm), and a reflectivity of more than 0.9 in most sunlight bands. The average emissivity in the atmospheric window band (8 to 13 μm) can reach 0.82 to 0.84, and the emissivity in most bands within the atmospheric window reaches more than 0.9.

[0041] The theoretical net radiative cooling power of the radiative cooling multilayer film structure that can present subtractive three primary color structural colors is 75.46W / m 2 ~84.56W / m 2 The temperature can be reduced by 10.9℃ to 12℃ compared to the ambient temperature of 30℃. The theoretical net radiative cooling power of the radiative cooling multilayer film structure that can present additive three primary color structural colors is 19.39W / m 2 ~43.56W / m 2 It can reduce the ambient temperature by 2.6℃ to 6℃ compared to 30℃.

[0042] In the preferred multilayer film structure that can present the three primary colors of subtraction: quartz glass (SiO2) or polished silicon wafer (Si) is used as the base material. For the three structures presenting light cyan (Cyan), light magenta (Magenta) and light yellow (Yellow): the thickness of Si3N4 in the radiation refrigerator is 900nm, and the thickness of SiO2 is 330-425nm respectively; the thickness of SiO2 in the two-period one-dimensional quasi-photonic crystal in the color former is 50-90nm, the thickness of TiO2 is 30-60nm, the thickness of SiO2 in the MIM structure is 90-170nm, the thickness of the top layer Ag is 70-80nm, and the thickness of the bottom layer Ag is 100nm.

[0043] In the preferred multilayer film structure that can present the additive three primary colors: quartz glass (SiO2) or polished silicon wafer (Si) is used as the base material. For the three structures presenting light red (Red), light green (Green) and light blue (Blue): the thickness of Si3N4 in the radiation refrigerator is 900nm, and the thickness of SiO2 is 325-425nm respectively; the thickness of SiO2 in the two-period one-dimensional quasi-photonic crystal in the color former is 50-90nm, the thickness of TiO2 is 30-60nm, the thickness of SiO2 in the MIM structure is 90-140nm, the thickness of the top layer Ag is 15-30nm, and the thickness of the bottom layer Ag is 45-100nm.

[0044] The preferred radiative cooling multilayer film with structural color described in the present invention has a reflectivity of 89.38% to 95.46% in the sunlight band (0.3 to 4 μm), and a reflectivity of up to 90% in most sunlight bands. The average emissivity in the atmospheric window band (8 to 13 μm) can reach 0.82 to 0.84, and the emissivity in most bands within the atmospheric window reaches above 0.9. At the same time, the preferred radiation cooling multilayer film can adjust the position of the resonance mode in the visible light band by changing the structural size, thereby controlling the position, number and size of the reflection valley to present the subtractive / additive three-primary color structural colors: light purple (0.31, 0.30, 85.30), light cyan (0.30, 0.33, 95.93) and light yellow (0.33, 0.36, 97.15); light red (0.35, 0.35, 84.24), light green (0.33, 0.37, 94.12) and light blue (0.29, 0.32, 84.02). On the basis of presenting the above structural colors, the multilayer film structure can also maintain good radiation cooling performance. When the structure is the same as the ambient temperature of 30°C, the net radiation cooling power of the preferred radiation cooling multilayer film is 19.39W / m 2 ~84.56W / m 2 . When the net cooling power is 0, the three radiation cooling multilayer films can achieve a temperature reduction of 2.6°C to 12°C compared to the ambient temperature of 30°C. On the basis of ensuring the radiation cooling capacity, more structural colors can be presented by adjusting the thickness of the dielectric layer in the MIM structure, the thickness of each layer of the two-period one-dimensional quasi-photonic crystal, or the thickness of the intermediate metal layer. And the multilayer film structure described in the present invention is easy to process. The present invention is further described below in conjunction with the accompanying drawings.

[0045] Figure 1 It is a schematic structural diagram of the radiation-generated multilayer film with structural color described in the present invention.

[0046] Figure 2This is the full-band (0.3-24 μm) emissivity curve of the preferred radiation cooling multilayer film presenting subtractive three primary colors. The absorptivity A of 0.3-24 μm is calculated using the transfer matrix method (TMM) to obtain the reflectivity R and transmittance T of the multilayer film structure. According to the law of energy conservation, the absorptivity of the structure can be: A=1-TR. Finally, according to Kirchhoff's law, the absorptivity is equal to the emissivity ratio ε=A, and the emissivity curve of the radiation cooling multilayer film in the 0.3-24 μm band can be obtained.

[0047] Among them, the calculation results show that the three preferred subtractive three-primary color radiation cooling multilayer films of the present invention have high emissivity in the atmospheric window band, and most bands can be maintained above 0.9. In the 0.3-2.5μm sunlight band, the emissivity of the three preferred radiation cooling multilayer films is below 0.1 in all bands except the band generated by the resonance mode. And the absorption peak generated by the resonance mode is extremely narrow. This narrow-band absorption characteristic greatly reduces the weakening effect of structural coloration on the sunlight reflection ability.

[0048] Among them, the overall reflection capacity of the sunlight band According to the formula:

[0049]

[0050] Calculated, where I AM1.5 (λ) is the direct sunlight irradiance, A(λ,θ Sun ) is the absorption rate of sunlight by the radiation cooling multilayer film at normal incidence. The calculation results show that the overall sunlight reflection capacity of the three preferred subtractive three-primary color radiation cooling multilayer films designed by the present invention is It can reach 95.24% to 95.46%.

[0051] Figure 3 It is the full-band (0.3-24 μm) emissivity curve of the preferred radiative cooling multilayer film presenting additive three primary colors. The emissivity curve is also obtained by the transfer matrix method (TMM).

[0052] The calculation results show that the three preferred additive three-primary color radiation cooling multilayer films of the present invention also have high emissivity in the atmospheric window band, and most bands can be maintained above 0.9. In the 0.3-2.5μm sunlight band, the emissivity of the three preferred radiation cooling multilayer films is below 0.1 except for the two bands generated in the resonance mode. The overall reflectivity in the sunlight band In terms of the overall sunlight reflection capacity of the three preferred additive three-primary color radiation cooling multilayer films designed by the present invention, It can reach 89.38% to 91.88%.

[0053] Figure 4 It is the subtractive three primary color structural color presented by the preferred radiative cooling multilayer film and the color coordinates of the corresponding structural color in the CIE 1931 color space. Among them, the color coordinates (x, y) and color brightness Y in the CIE 1931 color space can be calculated according to the formula:

[0054]

[0055]

[0056]

[0057]

[0058]

[0059] Y=Y

[0060] Calculated, where R(λ) is the reflectivity of the radiative cooling multilayer film in the 0.36-0.83 μm band, D65(λ) is the spectral energy distribution of the D65 artificial daylight source, and Represents the color matching function of the CIE 1931 color space, where k is the normalization coefficient.

[0061] Among them, the calculation results show that the multilayer film can present light purple (Magenta), light cyan (Cyan) and light yellow (Yellow), that is, the subtractive three-primary color structural colors, and the color coordinates (x, y, Y) in the CIE 1931 chromaticity diagram are Magenta (0.31, 0.30, 85.30), Cyan (0.30, 0.33, 95.93) and Yellow (0.33, 0.36, 97.15), respectively.

[0062] Figure 5 It is the additive three-primary color structural color presented by the preferred radiative cooling multilayer film and the color coordinates of the corresponding structural color in the CIE 1931 color space.

[0063] Among them, the calculation results show that the multilayer film can present light red (Red), light green (Green) and light blue (Blue), that is, the subtractive three-primary color structural colors, and the color coordinates (x, y, Y) in the CIE 1931 chromaticity diagram are Red (0.35, 0.35, 84.24), Green (0.33, 0.37, 94.12) and Blue (0.29, 0.32, 84.02), respectively.

[0064] Figure 6The theoretical daytime radiative cooling power curve of the preferred radiative cooling multilayer film presenting subtractive three primary colors. The net radiative cooling power P of the radiative cooling multilayer film net According to the formula:

[0065] P net =P rad -P atm -P sun -P conv

[0066]

[0067]

[0068]

[0069] P conv =h c (T atm -T S )

[0070] Calculated, where P rad is the radiation energy emitted outward by the radiation cooling multilayer film, P atm is the atmospheric radiation energy absorbed by the radiative cooling multilayer film, P sun is the solar energy absorption of the radiative cooling multilayer film, P conv It is the additional energy absorption caused by the heat transfer processes such as heat conduction and convection of the radiative cooling multilayer film. atm is the ambient temperature, set to 30℃(303K), T S is the surface temperature of the radiative cooling multilayer film, ε atm (λ, θ) is the atmospheric emissivity, ε(λ, θ) is the emissivity of the radiative cooling multilayer film, I bb (T S , λ) is the blackbody spectral radiation intensity of the radiative cooling multilayer film, I bb (T atm ,λ) is the blackbody spectral radiation intensity in the atmospheric environment. c is the heat transfer coefficient of the additional convection heat conduction process, considering the natural air convection condition, h c Set to 4W / (m 2 ·K).

[0071] The calculation results show that the theoretical net radiative cooling power of the structural color radiative cooling multilayer film is 77.91 W / m 2 (Magenta), 84.56W / m 2 (Cyan) and 75.46W / m 2(Yellow). It can achieve a temperature reduction of 11.1℃ (Magenta), 12℃ (Cyan) and 10.9℃ (Yellow) compared to an ambient temperature of 30℃.

[0072] Figure 7 It is the theoretical daytime radiative cooling power curve of the preferred radiative cooling multilayer film presenting additive three primary colors.

[0073] The calculation results show that the theoretical net radiative cooling power of the structural color radiative cooling multilayer film is 19.39W / m 2 (Red), 41.19W / m 2 (Green) and 43.35W / m 2 (Blue). It can achieve a temperature reduction of 2.6°C (Red), 5.6°C (Green) and 6°C (Blue) compared to an ambient temperature of 30°C.

[0074] Figure 8 The multiple colors that the radiation cooling multilayer film can present and the corresponding net radiation cooling power. By changing the thickness of the dielectric layer in the MIM structure, the thickness of each layer of the two-period one-dimensional quasi-photonic crystal or the thickness of the intermediate metal layer, the band, peak size and number of peaks of the reflection valley can be adjusted, thereby presenting a variety of structural colors.

[0075] The radiative cooling multilayer film structure with structural color described in the present invention realizes that the structure presents structural color through spectral absorption peaks while ensuring the radiative cooling effect through the narrow-band reflection valley presented by the color former structure in a specific band of visible light and the broadband high reflection characteristics in other bands of sunlight, as well as the high emission characteristics of the radiative cooler in the atmospheric window band. Compared with the conventional radiative cooling structure at present, the radiative cooling multilayer film described in the present invention can present a variety of colors, which solves the problem of limited application space caused by the single color of the existing conventional radiative cooling structure, and solves the problem that the existing structural color radiative cooling micro-nano photonic devices present limited colors or are difficult to process. Compared with the pigment coloring radiative cooling structure, the radiative cooling multilayer film has the great advantages of high coloring stability, strong corrosion resistance, and never fading in various environments through structural color coloring. Compared with the existing structural color radiative cooling photonic devices, the radiative cooling multilayer film has the great advantages of presenting a wide range of colors, simple processing, and low cost.

[0076] In the description of the present application, it should be understood that the terms "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0077] The above describes the specific embodiments of the present invention. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art can make various changes or modifications within the scope of the claims, which does not affect the essence of the present invention. In the absence of conflict, the embodiments of the present application and the features in the embodiments can be combined with each other arbitrarily.

Claims

1. A radiative cooling multilayer film structure with structural color, characterized in that: It includes a one-dimensional multilayer film structure, wherein the one-dimensional multilayer film structure includes a top radiation cooler structure and a bottom color former structure, wherein the color former structure includes a MIM structure and a two-period one-dimensional quasi-photonic crystal structure stacked from bottom to top; The two-periodic one-dimensional quasi-photonic crystal structure is composed of two dielectric films with different refractive indices stacked alternately, wherein the low-refractive index material is one of SiO2, MgF2, and CaF2, and the high-refractive index material is one of TiO2, HfO2, and SiC; the two-periodic one-dimensional quasi-photonic crystal structure cooperates with the top metal layer of the MIM structure; The radiation cooler structure is composed of one or more materials of SiO2, Si3N4, and Al2O3; Ag is used as the metal layer material of the MIM structure, and SiO2 is used as the dielectric layer material of the MIM structure; The thickness of the bottom Ag layer ranges from 40 to 100 nm, the thickness of the top Ag layer ranges from 10 to 80 nm, and the thickness of the SiO2 layer ranges from 90 to 170 nm; SiO2 and TiO2 are used as materials for the two-period one-dimensional quasi-photonic crystal, the thickness of the SiO2 layer is in the range of 50 to 100 nm, and the thickness of the TiO2 layer is in the range of 20 to 60 nm; SiO2 and Si3N4 are used as the materials of the radiation cooler, the thickness of the Si3N4 layer is set to 900nm, and the thickness of the SiO2 layer is 325nm~425nm; The one-dimensional multilayer film structure presents structural colors of subtractive three primary colors and additive three primary colors, which are light purple, light cyan and light yellow; light red, light green and light blue; The color coordinates (x, y, Y) of the one-dimensional multilayer film structure in the CIE 1931 chromaticity diagram are light purple (0.31, 0.30, 85.30), light cyan (0.30, 0.33, 95.93) and light yellow (0.33, 0.36, 97.15); light red (0.35, 0.35, 84.24), light green (0.33, 0.37, 94.12) and light blue (0.29, 0.32, 84.02).

2. The radiative cooling multilayer film structure with structural color according to claim 1, characterized in that: The total thickness of the one-dimensional multilayer film structure is 1.657 μm to 1.87 μm.

3. The radiative cooling multilayer film structure with structural color according to claim 1, characterized in that: The metal layer material of the MIM structure is one of Ag, Au or Al, and the dielectric layer material is one of SiO2, Al2O3, TiO2, HfO2, Si3N4.

4. The radiative cooling multilayer film structure with structural color according to claim 1, characterized in that: The theoretical net radiative cooling power of the radiative cooling multilayer film showing subtractive three-primary color structural color is 75.46W / m 2 ~84.56W / m 2 , achieving a 10.9℃~12℃ reduction compared to the ambient temperature of 30℃; The theoretical net radiative cooling power of the radiative cooling composite coating with additive three-primary color structural color is 19.39W / m 2 ~43.56W / m 2 , achieving a 2.6℃~6℃ reduction compared to the ambient temperature of 30℃.

5. The radiative cooling multilayer film structure with structural color according to claim 1, characterized in that: One-dimensional multilayer film structures use quartz glass or silicon as substrate materials.

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