Solar energy absorbing structure and solar energy absorbing device
By using the structure of a metal substrate, a dielectric layer and a microstructure array in the solar energy absorber, the surface plasmon resonance effect is stimulated, and the problem that the prior art is difficult to achieve high absorption in the entire band is solved, and efficient solar energy absorption is achieved.
Patent Information
- Application Number
- CN202421780369.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-25
- Publication Date
- 2025-05-06
- Estimated Expiration
- 2034-07-25
AI Technical Summary
It is difficult for existing solar absorbers to achieve high absorption in the entire band, especially in the main concentrated band of solar radiation energy (300nm~2500nm).
A solar energy absorption structure is adopted, including a metal substrate, a dielectric layer and a microstructure array. The microstructure array consists of interconnected tubes and spheres connected to the dielectric layer. The spheres are located in the cavity and come into contact with the dielectric layer, forming an inner cavity for limiting electrons, stimulating the surface plasmon resonance effect and enhancing the absorption efficiency.
The high absorption effect of the main concentrated band of solar radiation energy has been achieved, with an average absorption rate of 93.8%, and the highest absorption rate of a single absorption peak can reach 99.9%.
Smart Images
Figure CN222838200U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of solar energy absorption equipment, in particular to a solar energy absorption structure and a solar energy absorption device. Background Art
[0002] Perfect broadband absorption of light waves is a necessary condition for the efficient conversion of incident electromagnetic radiation energy into other forms of energy. However, among the various devices that can meet this optical goal, broadband absorbers perform very well. It is well known that metal nanoparticle array structures are important elements for achieving perfect absorption, but broadband absorption is affected by structure, period, size and shape. Its excellent performance has made ultra-broadband perfect absorbers widely concerned in solar absorbers.
[0003] Currently, the basic structure of most solar absorbers is composed of a bottom metal, a dielectric layer arranged on the bottom metal, and metal nano-units arranged on the dielectric layer. This structural composition is called a metal-dielectric-metal MIM structure. However, it is difficult for this MIM structure to meet the full-band high absorption requirements of the band where solar radiation energy is mainly concentrated (300nm~2500nm). Utility Model Content
[0004] In view of this, the utility model provides a solar energy absorption structure with high solar radiation energy absorption efficiency.
[0005] A solar energy absorption structure comprises a metal substrate, a dielectric layer and a microstructure array, wherein the dielectric layer is arranged on the metal substrate, the microstructure array is arranged on the dielectric layer, the microstructure array comprises a plurality of microstructure units, each microstructure unit comprises a tube body and a sphere connected to each other, and the tube body is connected to the dielectric layer.
[0006] In an embodiment of the utility model, the tube body is provided with a cavity running through both ends thereof, the diameter of the sphere is equal to the inner diameter of the cavity, the surface of the sphere is tangent to the cavity wall of the cavity, half of the sphere is located outside the cavity, and the other half of the sphere is located in the cavity.
[0007] In an embodiment of the present invention, the sphere is located at the bottom of the cavity and contacts the dielectric layer.
[0008] In an embodiment of the present invention, an inner cavity for confining electrons is formed between the cavity wall of the cavity and the dielectric layer.
[0009] In an embodiment of the present invention, the cavity comprises a first section and at least one second section, the inner diameter of the first section is different from the inner diameter of the second section, and the surface of the sphere is tangent to the cavity wall of the first section.
[0010] In an embodiment of the present invention, the plurality of microstructure units are arranged in a matrix, and the center distance between two adjacent microstructure units is 500 nm to 600 nm.
[0011] In an embodiment of the present invention, the metal substrate and the tube body are both made of titanium.
[0012] In an embodiment of the present invention, the dielectric layer and the spheres are both made of silicon dioxide.
[0013] In an embodiment of the present invention, the thickness of the metal substrate is 200 nm to 300 nm.
[0014] In an embodiment of the present invention, the thickness of the dielectric layer is 40 nm to 60 nm.
[0015] In an embodiment of the present invention, the outer diameter of the tube is 350 nm to 400 nm.
[0016] In an embodiment of the present invention, the diameter of the sphere is 150nm-200nm.
[0017] In an embodiment of the utility model, the above-mentioned metal substrate includes a plurality of interconnected substrate units, the dielectric layer includes a plurality of interconnected dielectric units, each of the microstructure units is arranged in one-to-one correspondence with each of the substrate units and each of the dielectric units, and the center lines of each of the microstructure units, each of the substrate units, and each of the dielectric units coincide.
[0018] The present application also relates to a solar energy absorption device, comprising the above-mentioned solar energy absorption structure.
[0019] The microstructure units of the solar energy absorption structure of the utility model can stimulate the surface plasmon resonance effect, thereby improving the absorption in the short wavelength range. In addition, there is a coupling effect between the microstructure units and the dielectric layer, which can further enhance the surface plasmon resonance effect and improve the absorption efficiency in the high-wavelength band. Therefore, the solar energy absorption structure of the present application can obtain a high absorption effect in the band where the solar radiation energy is mainly concentrated. BRIEF DESCRIPTION OF THE DRAWINGS
[0020] Figure 1 It is a schematic diagram of the partial structure of the solar energy absorption structure of the first embodiment of the present application.
[0021] Figure 2 yes Figure 1 Schematic diagram of the top view of the solar energy absorption structure shown.
[0022] Figure 3 It is a schematic diagram of a partial cross-sectional structure of the solar energy absorption structure of the first embodiment of the present application.
[0023] Figure 4 This is an absorption spectrum diagram obtained by the present application based on numerical simulation.
[0024] Figure 5 This is the absorption spectrum that this application intends to obtain to verify the sensitivity of polarization.
[0025] Figure 6 It is a schematic diagram of a partial cross-sectional structure of a solar energy absorption structure of the second embodiment of the present application. DETAILED DESCRIPTION
[0026] The following is an explanation of the implementation of the present application by means of specific embodiments. People familiar with the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification.
[0027] In the following description, reference is made to the accompanying drawings, which describe several embodiments of the present application. It should be understood that other embodiments may be used and that mechanical, structural, electrical, and operational changes may be made without departing from the spirit and scope of the present application. The following detailed description should not be considered limiting, and the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the present application.
[0028] Although the terms first, second, etc. are used herein to describe various elements in some instances, these elements should not be limited by these terms. These terms are only used to distinguish one element from another element.
[0029] Furthermore, as used in this article, the singular forms "one", "an" and "the" are intended to include plural forms as well, unless there is an indication to the contrary in the context. It should be further understood that the terms "comprise", "include" indicate the presence of features, steps, operations, elements, components, projects, kinds, and / or groups, but do not exclude the presence, occurrence or addition of one or more other features, steps, operations, elements, components, projects, kinds, and / or groups. The terms "or" and "and / or" used herein are interpreted as inclusive, or mean any one or any combination. Therefore, "A, B or C" or "A, B and / or C" means "any of the following: A; B; C; A and B; A and C; B and C; A, B and C". Only when the combination of elements, functions, steps or operations is inherently mutually exclusive in some way, will there be an exception to this definition.
[0030] First embodiment
[0031] Figure 1 is a partial structural schematic diagram of the solar energy absorption structure of the first embodiment of the present application, Figure 2 yes Figure 1 The schematic diagram of the top view of the solar energy absorption structure shown in FIG. Figure 3is a partial cross-sectional structural schematic diagram of the solar energy absorption structure of the first embodiment of the present application, such as Figure 1 , Figure 2 and Figure 3 As shown, the solar energy absorption structure includes a metal substrate 12, a dielectric layer 13 and a microstructure array 14, wherein the dielectric layer 13 is disposed on the metal substrate 12, the microstructure array 14 is disposed on the dielectric layer 13, and the microstructure array 14 includes a plurality of microstructure units 141, each microstructure unit 141 includes a tube body 1411 and a sphere 1412 connected to each other, and the tube body 1411 is connected to the dielectric layer 13. In this embodiment, the metal substrate 12 is used to prevent light from being transmitted therefrom.
[0032] The microstructure unit 141 of the solar energy absorption structure of the present application can excite the surface plasmon resonance effect, thereby improving the absorption in the short wavelength range, and there is a coupling effect between the microstructure unit 141 and the dielectric layer 13, which can further enhance the surface plasmon resonance effect and improve the absorption efficiency in the high-wavelength band. Therefore, the solar energy absorption structure of the present application can obtain a high absorption effect in the band where the solar radiation energy is mainly concentrated. For example, the solar energy absorption structure can achieve an average absorption rate of 93.8% at a bandwidth of 2200nm in the band where the solar radiation spectrum energy is mainly concentrated (300-2500nm), and the maximum absorption rate of a single absorption peak can reach up to 99.9%.
[0033] Alternatively, if Figure 3 As shown, the tube body 1411 is provided with a cavity 101 passing through both ends thereof, the diameter of the sphere 1412 is equal to the inner diameter of the cavity 101, the surface of the sphere 1412 is tangent to the cavity wall of the cavity 101, half of the sphere 1412 is located outside the cavity 101, and the other half of the sphere 1412 is located in the cavity 101.
[0034] Optionally, the sphere 1412 is located at the bottom of the cavity 101 and contacts the dielectric layer 13 .
[0035] Optionally, an inner cavity 102 for confining electrons is formed between the sphere 1412, the cavity wall of the cavity 101, and the dielectric layer 13. In this embodiment, the inner cavity 102 is used to confine free electrons generated by the microstructure unit 141 due to the surface plasmon resonance effect, and there is a coupling effect between the dielectric layer 13 and the tube body 1411 and the sphere 1412, which can further enhance the surface plasmon resonance effect.
[0036] Optionally, the plurality of microstructure units 141 are arranged in a matrix, and the center distance between two adjacent microstructure units 141 is 500nm-600nm, that is, the period L of the microstructure units 141 is 500nm-600nm, for example, 520nm, 540nm, 560nm, 580nm.
[0037] Optionally, the metal substrate 12 and the tube body 1411 are made of titanium or the same type of metal. In this embodiment, the metal substrate 12 and the tube body 1411 are made of non-precious metals, which can achieve high solar energy absorption rate and large-scale production and utilization.
[0038] Optionally, the materials of the dielectric layer 13 and the spheres 1412 are both silicon dioxide (SiO 2 ) or the same type of oxide.
[0039] Optionally, the thickness h1 of the metal substrate 12 is 200 nm to 300 nm, for example, 220 nm, 240 nm, 260 nm, or 280 nm.
[0040] Optionally, the thickness h2 of the dielectric layer 13 is 40 nm to 60 nm, for example, 42 nm, 44 nm, 46 nm, or 48 nm.
[0041] Optionally, the outer diameter d2 of the tube body 1411 is 350 nm to 400 nm, for example, 360 nm, 370 nm, 380 nm, or 390 nm.
[0042] Optionally, the height h3 of the tube body 1411 is 75 nm to 100 nm, for example, 80 nm, 85 nm, 90 nm, or 95 nm.
[0043] Optionally, the diameter d1 of the sphere 1412 is 150 nm to 200 nm, for example, 160 nm, 170 nm, 180 nm, or 190 nm.
[0044] Alternatively, if Figure 2 and Figure 3 As shown, the metal substrate 12 includes a plurality of interconnected substrate units 121, the dielectric layer 13 includes a plurality of interconnected dielectric units 131, each microstructure unit 141 is arranged in one-to-one correspondence with each substrate unit 121 and each dielectric unit 131, and the center lines of each microstructure unit 141, each substrate unit 121, and each dielectric unit 131 coincide with each other.
[0045] Optionally, the surface where the metal substrate 12 contacts the dielectric layer 13 is a first plane, and the surface where the dielectric layer 13 contacts the metal substrate 12 is a second plane, and the first plane and the second plane are bonded to each other.
[0046] The steps for making the solar energy absorption structure of the present application are as follows:
[0047] First, a metal substrate 12 is prepared by using PECVD deposition technology;
[0048] Then, a dielectric layer 13 is prepared on the metal substrate 12 by using PECVD deposition technology;
[0049] Next, the tube body 1411 and the sphere 1412 are manufactured by using photolithography and etching techniques, and the tube body 1411 and the sphere 1412 are connected together to form a microstructure unit 141;
[0050] Finally, a plurality of microstructure units 141 are fixed on the dielectric layer 13 to form a solar energy absorption structure.
[0051] The present application adopts the time-domain finite-difference method (FDTD) to simulate the minimum periodic structure of the solar energy absorption structure (a structure composed of the microstructure unit 141, the substrate unit 121, and the dielectric unit 131), sets corresponding boundary conditions for simulation, measures corresponding simulation results, and proves the beneficial effects of the solar energy absorption structure through the simulation data.
[0052] Specifically, a first direction X, a second direction Y and a third direction Z perpendicular to each other are defined, the surface of the metal substrate 12 is parallel to the first direction X and the second direction Y, and the third direction Z is the thickness direction of the metal substrate 12; the incident light source is a TM polarized plane wave, which is perpendicularly incident on the surface of the solar energy absorption structure. The first direction X and the second direction Y adopt the periodic boundary condition (PBC); the third direction Z adopts the perfect matching layer (PML) boundary condition. The period of the microstructure unit 141 is L = 500nm (the center distance between two adjacent microstructure units 141 is 500nm), the thickness of the dielectric layer 13 is h2 is 60nm; the height of the tube 1411 is h3 = 100nm, the outer diameter d2 of the tube 1411 is 380nm, the diameter d1 of the sphere 1412 is 200nm; the thickness h1 of the metal substrate 12 is 300nm. The material of the sphere 1412 and the dielectric layer 13 is silicon dioxide (SiO2), and the material of the metal substrate 12 and the tube 1411 is titanium (Ti). The dielectric constants of titanium and silicon dioxide were determined using the model in Palik (Handbook of Optical Constants of Solids I-III).
[0053] Figure 4 is the absorption spectrum obtained by numerical simulation in this application, such as Figure 4 As shown, the ordinate is the absorption value (absorption), and the abscissa is the wavelength (wavelength); at 730nm, the absorption peak with an absorption rate of more than 99% is obtained, at 580nm, the absorption peak with an absorption rate of more than 97% is obtained, and at 1172nm, the absorption peak with an absorption rate of more than 96% is obtained. It can be calculated that the average absorption rate in the range of 300nm to 2500nm is 93.80%.
[0054] Figure 5 This is the absorption spectrum that this application intends to obtain to verify the sensitivity of polarization, such as Figure 5As shown, in order to verify the polarization insensitivity of the solar energy absorption structure, the incident light source is set again as a plane wave with TE polarization. According to the absorption spectrum obtained by numerical simulation and the absorption rate comparison diagram of TE and TM light source modes, it can be seen that the absorption rate is not affected under TE and TM polarizations and the absorption curves are consistent, which also confirms the excellence of the designed symmetrical structure.
[0055] Second embodiment
[0056] Figure 6 FIG. 1 is a partial cross-sectional structural diagram of a solar energy absorption structure according to a second embodiment of the present application. Figure 6 As shown, the solar energy absorption structure of this embodiment is substantially the same as the solar energy absorption structure of the first embodiment, except that the local structure of the tube body 1411 is different. In this embodiment, the cavity 101 includes a first section 1011 and at least one second section 1012, the inner diameter of the first section 1011 is different from the inner diameter of the second section 1012, and the surface of the sphere 1412 is tangent to the cavity wall of the first section 1011. In this embodiment, the inner diameter of the second section 1012 is greater than the inner diameter of the first section 1011.
[0057] In other embodiments, the cavity 101 includes a first section 1011 and a plurality of second sections 1012 .
[0058] Third embodiment
[0059] The present application also relates to a solar energy absorption device, comprising the above-mentioned solar energy absorption structure.
[0060] The above embodiments are merely illustrative of the principles and effects of the present application and are not intended to limit the present application. Anyone familiar with the technology may modify or change the above embodiments without violating the spirit and scope of the present application. Therefore, all equivalent modifications or changes made by a person of ordinary skill in the art without departing from the spirit and technical ideas disclosed in the present application shall still be covered by the claims of the present application.
Claims
1. A solar energy absorption structure, characterized in that: It includes a metal substrate, a dielectric layer and a microstructure array, wherein the dielectric layer is arranged on the metal substrate, the microstructure array is arranged on the dielectric layer, the microstructure array includes a plurality of microstructure units, each of the microstructure units includes a tube body and a sphere connected to each other, and the tube body is connected to the dielectric layer.
2. The solar energy absorption structure according to claim 1, characterized in that: The tube body is provided with a cavity running through both ends thereof, the diameter of the sphere is equal to the inner diameter of the cavity, the surface of the sphere is tangent to the cavity wall of the cavity, half of the sphere is located outside the cavity, and the other half of the sphere is located in the cavity.
3. The solar energy absorption structure according to claim 2, characterized in that: The bottom of the sphere located in the cavity contacts the dielectric layer.
4. The solar energy absorption structure according to claim 3, characterized in that: An inner cavity for confining electrons is formed between the sphere, the cavity wall of the cavity channel and the dielectric layer.
5. The solar energy absorption structure according to claim 3, characterized in that: The cavity includes a first section and at least one second section, the inner diameter of the first section is different from the inner diameter of the second section, and the surface of the sphere is tangent to the cavity wall of the first section.
6. The solar energy absorption structure according to claim 1, characterized in that: The plurality of microstructure units are arranged in a matrix, and the center distance between two adjacent microstructure units is 500nm to 600nm.
7. The solar energy absorption structure according to any one of claims 1 to 6, characterized in that: Include at least one of the following: The metal substrate and the tube body are made of titanium; The dielectric layer and the spheres are both made of silicon dioxide.
8. The solar energy absorption structure according to any one of claims 1 to 6, characterized in that: Include at least one of the following: The thickness of the metal substrate is 200nm to 300nm; The thickness of the dielectric layer is 40nm to 60nm; The outer diameter of the tube is 350nm to 400nm; The diameter of the sphere is 150nm-200nm.
9. The solar energy absorption structure according to any one of claims 1 to 6, characterized in that: The metal substrate includes a plurality of interconnected substrate units, the dielectric layer includes a plurality of interconnected dielectric units, each of the microstructure units is arranged in one-to-one correspondence with each of the substrate units and each of the dielectric units, and the center lines of each of the microstructure units, each of the substrate units, and each of the dielectric units coincide.
10. A solar energy absorption device, characterized in that: A solar energy absorption structure comprising the solar energy absorption structure according to any one of claims 1 to 9.