A reflective panel and a method for preparing the same

Abstract

The present application discloses a reflective panel and a method for manufacturing the same, wherein the reflective panel comprises: a substrate; and a plurality of optoelectronic structure units located on the substrate, each of the plurality of optoelectronic structure units being capable of generating a photoelectric effect for light of a specific frequency; wherein when light of a specific frequency irradiates the reflective panel, the photoelectric effect generated by the plurality of optoelectronic structure units causes the electromagnetic properties of the reflective panel to change.

Description

Technical Field

[0001] The present application relates to the field of metamaterial technology, and in particular to a smart reflective panel based on light-controlled response and a preparation method thereof. Background Art

[0002] A metasurface is a surface structure with extraordinary physical properties, which are reflected in electromagnetic properties. The electromagnetic properties of a metasurface can be regulated, and a metasurface that can regulate electromagnetic properties is also called a smart reflective surface.

[0003] At present, the electromagnetic properties of metasurfaces are regulated by electrical control, and such metasurfaces are also called electrically controlled intelligent reflective surfaces. Specifically, the metasurface has adjustable components (such as variable capacitors, switching diodes, etc.), and the adjustable components on the metasurface are regulated by electrical control (such as changing the size of the capacitor, controlling the on and off of the diode, etc.), thereby achieving regulation of the electromagnetic properties of the metasurface. However, there is a need for power feeding to regulate the adjustable components on the metasurface by electrical control. In actual applications, the installation point of the metasurface may not necessarily meet its demand for power feeding, and a new control mechanism is needed to achieve regulation of the electromagnetic properties of the metasurface. Summary of the invention

[0004] In order to solve the above technical problems, an embodiment of the present application provides a reflective panel and a method for preparing the same.

[0005] The reflective panel provided in the embodiment of the present application includes:

[0006] substrate; and,

[0007] A plurality of optoelectronic structural units located on the substrate, each of the plurality of optoelectronic structural units being capable of generating a photoelectric effect for light of a specific frequency;

[0008] When light of a specific frequency illuminates the reflective panel, the photoelectric effect generated by the multiple photoelectric structural units causes the electromagnetic properties of the reflective panel to change.

[0009] In some optional embodiments of the present application, the substrate has a plurality of groove structures, and the plurality of groove structures correspond one-to-one to the plurality of optoelectronic structure units, wherein one optoelectronic structure unit is located in one groove structure.

[0010] In some optional embodiments of the present application, the optoelectronic structure unit includes:

[0011] a semiconductor layer, the semiconductor layer covering the substrate; and

[0012] A metal layer covers the semiconductor layer.

[0013] In some optional embodiments of the present application, the semiconductor layer is a doped zinc oxide thin film.

[0014] In some optional embodiments of the present application, the metal layer is a silver nanowire film.

[0015] In some optional embodiments of the present application, the metal layer is a transparent metal layer.

[0016] In some optional embodiments of the present application, the substrate is a transparent substrate.

[0017] In some optional embodiments of the present application, the plurality of optoelectronic structure units are periodically distributed on the substrate.

[0018] The method for preparing a reflective panel provided in an embodiment of the present application includes:

[0019] Obtaining a substrate;

[0020] Carving a plurality of groove structures on the substrate;

[0021] Manufacturing a plurality of optoelectronic structure units in the plurality of groove structures to obtain a reflective panel;

[0022] Each of the plurality of optoelectronic structure units can generate a photoelectric effect for light of a specific frequency.

[0023] In some optional embodiments of the present application, before engraving a plurality of groove structures on the substrate, the method further comprises: covering the substrate with a mask;

[0024] The step of carving a plurality of groove structures on the substrate comprises: carving a plurality of groove structures on a substrate covered with a mask.

[0025] In some optional embodiments of the present application, after engraving a plurality of groove structures on the substrate covered with the mask, the method further includes:

[0026] The substrate with the plurality of groove structures is placed in an acid solution and cleaned by ultrasound.

[0027] In some optional embodiments of the present application, the manufacturing of multiple optoelectronic structure units in the multiple groove structures includes:

[0028] Preparation of semiconductor dispersions and metal dispersions;

[0029] Spraying the semiconductor dispersion liquid and the metal dispersion liquid sequentially on the substrate with the plurality of groove structures;

[0030] Among them, the semiconductor dispersion forms a semiconductor layer after being air-dried, and the metal dispersion forms a metal layer after being air-dried, the semiconductor layer is covered on the substrate, and the metal layer is covered on the semiconductor layer; the semiconductor layer and the metal layer in each of the multiple groove structures form a photoelectric structure unit, and multiple photoelectric structure units are formed in the multiple groove structures.

[0031] In some optional embodiments of the present application, the semiconductor layer is a doped zinc oxide film, and the preparation of the semiconductor dispersion comprises:

[0032] Pour the doping material of zinc salt and metal salt into an aqueous solution, add a coupling agent, and stir and mix to obtain a precursor;

[0033] The precursor is prepared into doped zinc oxide powder by a solvothermal method;

[0034] The doped zinc oxide powder is dispersed in an aqueous solution to obtain a doped zinc oxide dispersion.

[0035] In some optional embodiments of the present application, the metal layer is a silver nanowire film, and the metal dispersion is prepared, comprising:

[0036] The silver nanowires are dispersed in an aqueous solution to obtain a silver nanowire dispersion.

[0037] In some optional embodiments of the present application, after a plurality of optoelectronic structure units are manufactured in the plurality of groove structures, the method further comprises:

[0038] The substrate with the plurality of optoelectronic structure units is subjected to annealing treatment, so that the mask on the surface of the substrate is decomposed.

[0039] In some optional embodiments of the present application, the substrate is a transparent substrate.

[0040] In the technical solution of the embodiment of the present application, a reflective panel based on a new regulation mechanism is proposed, namely, an intelligent reflective panel based on light control response (hereinafter referred to as a light control intelligent reflective panel). The reflective panel includes a substrate and a plurality of photoelectric structural units located on the substrate. When light of a specific frequency irradiates the reflective panel, the plurality of photoelectric structural units can produce a photoelectric effect, causing the electromagnetic performance of the reflective panel to change. Since the electromagnetic performance of the reflective panel is regulated by light control, there is no need for feeding, and no feeding line is required on the reflective panel. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 It is a physical picture of an electrically controlled intelligent reflective surface;

[0042] Figure 2 is a schematic diagram of a structural unit in an electrically controlled intelligent reflective surface;

[0043] Figure 3 It is a production flow chart of the electrically controlled intelligent reflective surface;

[0044] Figure 4 This is a schematic diagram of the structure of the reflective panel provided in the embodiment of the present application. Figure 1 ;

[0045] Figure 5 It is a side view of the optoelectronic structure unit provided in the embodiment of the present application embedded in the substrate;

[0046] Figure 6 It is a schematic diagram of the composition of the optoelectronic structure unit provided in the embodiment of the present application;

[0047] Figure 7 This is a schematic diagram of the lighting scene of the optoelectronic structure unit provided in the embodiment of the present application. Figure 1 ;

[0048] Figure 8 This is a schematic diagram of the lighting scene of the optoelectronic structure unit provided in the embodiment of the present application. Figure 2 ;

[0049] Fig. 9 This is a schematic diagram of the lighting scene of the optoelectronic structure unit provided in the embodiment of the present application. Figure 3 ;

[0050] Fig.10 This is a schematic diagram of the structure of the reflective panel provided in the embodiment of the present application. Figure 2 ;

[0051] Fig.11 The process diagram of the method for preparing the reflective panel provided in the embodiment of the present application is as follows Figure 1 ;

[0052] Fig.12 The process diagram of the method for preparing the reflective panel provided in the embodiment of the present application is as follows Figure 2 . DETAILED DESCRIPTION

[0053] The exemplary embodiments disclosed in the present application will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present application are shown in the accompanying drawings, it should be understood that the present application can be implemented in various forms and should not be limited by the specific embodiments described herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present application and to fully convey the scope disclosed in the present application to those skilled in the art.

[0054] In the following description, a large number of specific details are given to provide a more thorough understanding of the present application. However, it is obvious to those skilled in the art that the present application can be implemented without one or more of these details. In other examples, in order to avoid confusion with the present application, some technical features known in the art are not described; that is, all features of the actual embodiments are not described here, and well-known functions and structures are not described in detail.

[0055] In the drawings, the sizes of layers, regions, elements and their relative sizes may be exaggerated for clarity. Like reference numerals denote like elements throughout.

[0056] It should be understood that when an element or layer is referred to as "on ...", "adjacent to ...", "connected to" or "coupled to" other elements or layers, it can be directly on, adjacent to, connected to or coupled to other elements or layers, or there can be intervening elements or layers. On the contrary, when an element is referred to as "directly on ...", "directly adjacent to ...", "directly connected to" or "directly coupled to" other elements or layers, there is no intervening element or layer. It should be understood that although the terms first, second, third, etc. can be used to describe various elements, components, regions, layers and / or parts, these elements, components, regions, layers and / or parts should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or part from another element, component, region, layer or part. Therefore, without departing from the teachings of the present application, the first element, component, region, layer or part discussed below can be represented as the second element, component, region, layer or part. And when the second element, component, region, layer or part is discussed, it does not indicate that the present application necessarily has the first element, component, region, layer or part.

[0057] Spatially relative terms such as "under", "beneath", "below", "under", "above", "above", etc., may be used here for convenience of description to describe the relationship between an element or feature shown in the figure and other elements or features. It should be understood that in addition to the orientation shown in the figure, the spatial relationship terms are intended to also include different orientations of the device in use and operation. For example, if the device in the accompanying drawings is turned over, then the elements or features described as "under other elements" or "under it" or "under it" will be oriented as "on" other elements or features. Therefore, the exemplary terms "under" and "under" may include both upper and lower orientations. The device can be oriented otherwise (rotated 90 degrees or other orientations) and the spatial descriptors used herein are interpreted accordingly.

[0058] The purpose of the terms used herein is only to describe specific embodiments and is not intended to be limiting of the present application. When used herein, the singular forms "one", "an" and "said / the" are also intended to include plural forms, unless the context clearly indicates otherwise. It should also be understood that the terms "consisting of" and / or "comprising", when used in this specification, determine the presence of the features, integers, steps, operations, elements and / or parts, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, parts and / or groups. When used herein, the term "and / or" includes any and all combinations of the relevant listed items.

[0059] To facilitate understanding of the technical solutions of the embodiments of the present application, the relevant technologies of the embodiments of the present application are first described below.

[0060] Being able to control electromagnetic waves at will has always been a dream that people have been pursuing. The emergence of Maxwell's equations has enabled humans to rapidly increase their ability to control electromagnetic waves. However, in current wireless networks, wireless signals will be absorbed by objects in the transmission environment and naturally diffuse in the space when they are transmitted from the transmitter to the receiver, resulting in a certain degree of attenuation and scattering of the wireless signals, which increases the computational complexity of signal recovery at the receiver and reduces performance. Therefore, due to the limitation of the uncontrollability of the wireless channel environment, in the research and design of various traditional mobile communication systems, various wireless channel environments can only be passively measured and modeled, and then transmitters and receivers are carefully designed on this basis to offset the adverse effects of the wireless channel or use its characteristics to optimize the design of wireless communication systems. However, such solutions are time-consuming and labor-intensive. For example, in the 5G network and the future 6G mobile network, which have achieved a significant increase in network capacity and real-time connection of multiple devices, in order to achieve efficient and stable transmission of wireless signals, ultra-dense network key technologies are indispensable, but the accompanying high hardware cost, high complexity, high energy consumption and other problems are also unavoidable. In actual scenarios, for example, for users in the blind spots of macro base station coverage and users at the edge of the cell, it is usually necessary to set up repeaters and relays in areas where the direct link between the user and the service base station is severely blocked by obstacles, in order to increase coverage, fill blind spots and other functions.

[0061] Until the emergence of metasurfaces, it became possible to change and control the wireless channel environment. By constructing a periodically arranged metal or dielectric array and designing its structure in an orderly manner at key physical scales, a surface structure with extraordinary physical properties, namely a metasurface, can be prepared. The electromagnetic parameters of the metasurface determine its electromagnetic properties. The electromagnetic parameters depend on the resonant characteristics of the basic constituent units of the metasurface (called structural units), and can achieve negative dielectric constants ε and magnetic permeability μ. However, once the structure of the metasurface is designed and manufactured, its electromagnetic properties are fixed. With the development of metasurface technology, it is proposed that the structural units of the metasurface can be equivalent to RLC circuits, and then adjustable components (such as variable capacitors, switching diodes, etc.) can be added to the equivalent circuit. By adjusting the performance of the adjustable components, the electromagnetic properties of each structural unit can be changed. The metasurface with added adjustable components is also called an intelligent reflective surface based on electrically controlled response (abbreviated as electrically controlled intelligent reflective surface), such as Figure 1 and Figure 2 As shown, Figure 1 This is a physical picture of an electrically controlled intelligent reflective surface. Figure 2 It is a schematic diagram of the structural unit in the electrically controlled intelligent reflecting surface.

[0062] Metasurfaces with adjustable components can present unconventional physical phenomena, such as negative refraction, wave absorption, focusing, unconventional reflection, etc. This kind of metasurface that realizes real-time manipulation of electromagnetic waves has attracted widespread attention from academia and industry because it can overcome the negative impact of the natural wireless propagation environment by actively controlling the electromagnetic properties of electromagnetic waves, thereby greatly improving the channel environment, and then achieving the goal of improving communication performance and realizing the special potential of intelligent electromagnetic environment.

[0063] For the electrically controlled intelligent reflective surface, its production flow chart is as follows: Figure 3 As shown, it generally includes the following steps:

[0064] Step 301: On a copper-clad laminate of paper, glass cloth or synthetic fiber, a printed circuit board (PCB) having a metasurface structure is prepared by performing a series of operations such as exposure and demolding on a photopolymerized or photodecomposed dry film, i.e., a circuit film, which is covered with metasurface structure units.

[0065] Step 302: Using surface mount technology (SMT), adjustable components such as PIN diodes, varactor diodes, and variable capacitors are mounted on the PCB according to design requirements.

[0066] Step 303: Connect to the feeding network to complete the production of the electrically controlled intelligent reflective surface.

[0067] The reason why the electrically controlled intelligent reflective surface can realize real-time control of electromagnetic waves is due to the adjustable electromagnetic characteristics of each structural unit on its panel. In the electrically controlled intelligent reflective surface, the changes in the electromagnetic characteristics of each structural unit are due to the regulation of adjustable components, such as changing the size of the capacitor, controlling the on and off of the diode, etc. Obviously, the electrically controlled intelligent reflective surface has a feeding demand. However, in actual application, the installation point of the electrically controlled intelligent reflective surface may not be able to meet its feeding needs, so a new control mechanism is needed to realize the regulation of the electromagnetic characteristics of the metasurface; in addition, in certain specific scenarios, such as installing an intelligent reflective surface on the glass wall of a high-rise building or on the glass of a car, there are higher requirements for the transparency of the panel. If the intelligent reflective surface has transparent characteristics, it is easier to be accepted by customers. Obviously, it is difficult for existing intelligent reflective surfaces to meet such application requirements.

[0068] To this end, the following technical solutions of the embodiments of the present application are proposed. It should be noted that the "reflective panel" described in the embodiments of the present application can also be understood as a "reflective surface" or a "reflective surface panel", that is, the description of the "reflective panel" can be replaced by a "reflective surface" or a "reflective surface panel".

[0069] The technical solution of the embodiment of the present application proposes an intelligent reflective panel based on a new control mechanism - an intelligent reflective panel based on light-controlled response (referred to as light-controlled intelligent reflective panel), the theoretical basis of which is the photoelectric effect. The photoelectric effect is explained below.

[0070] According to the theory proposed by Hertz and Einstein, when a photon irradiates a light-sensitive material (called a photoelectric material), the incident light energy can be absorbed by the valence band electrons in the material. The electrons that absorb the photon energy will then convert the energy into kinetic energy. If the absorbed energy is sufficient to support the electrons to overcome the attraction of the nucleus to them, the electrons can be excited to the conduction band. At this time, a hole will be left in the valence band, forming a pair of electrons that can conduct electricity, i.e., a hole pair. After further absorbing enough photon energy, they can escape from the surface in a very short time (one billionth of a second) and become photoelectrons, realizing the photoelectric effect of directly converting light energy into electrical energy. The occurrence of the photoelectric effect will increase the carrier concentration in the material, causing changes in conductivity and dielectric properties. This photoelectric effect, in which the physical properties of the material are changed by light, provides a theoretical basis for light-controlled smart reflective surfaces.

[0071] The technical solution of the embodiment of the present application starts with the photoelectric effect of the photoelectric material, and replaces the existing substrate by selecting a substrate, and then deposits a photoelectric structural unit (i.e., a structural unit realized by the photoelectric material) on the substrate with an ordered periodic structural pattern in combination with magnetron sputtering technology. It is then irradiated with light of a specific frequency to induce the photoelectric effect. The free electrons excited by the photoelectric effect produce directional movement, forming a current, causing the electronic polarization to be enhanced, and the dielectric properties of the reflective panel to change. According to the impedance calculation formula, the change in dielectric properties is bound to lead to a change in input impedance. According to the reflection loss calculation formula, the difference between the characteristic impedance and the free space impedance will inevitably cause reflection loss, that is, cause a change in reflectivity.

[0072] Figure 4 This is a schematic diagram of the structure of the reflective panel provided in the embodiment of the present application. Figure 1 ,like Figure 4 As shown, the reflective panel includes:

[0073] a substrate 41; and

[0074] A plurality of photoelectric structure units 42 located on the substrate 41, each of the plurality of photoelectric structure units 42 being capable of generating a photoelectric effect for light of a specific frequency;

[0075] When light of a specific frequency illuminates the reflective panel, the photoelectric effect generated by the plurality of photoelectric structure units 42 causes the electromagnetic performance of the reflective panel to change.

[0076] In the embodiment of the present application, the plurality of optoelectronic structure units 42 are periodically distributed on the substrate 41. In some optional embodiments, the plurality of optoelectronic structure units are periodically distributed along a specific direction on the substrate. In some optional embodiments, the plurality of optoelectronic structure units are periodically distributed along multiple specific directions on the substrate. For example, the plurality of optoelectronic structure units are periodically distributed along two perpendicular directions on the substrate.

[0077] In the embodiment of the present application, the distribution pattern of the multiple optoelectronic structures on the substrate can be flexibly set according to the application scenario. As a feature of the distribution pattern, the intervals between the optoelectronic structures can be flexibly set.

[0078] In the embodiment of the present application, multiple optoelectronic structure units are embedded in the substrate. Specifically, the substrate 41 has multiple groove structures, and the multiple groove structures correspond one-to-one to the multiple optoelectronic structure units 42, wherein one optoelectronic structure unit 42 is located in one groove structure.

[0079] As an example, Figure 5 A side view of a photovoltaic structure unit embedded in a substrate is given. It should be noted that Figure 5 The surface of the optoelectronic structure unit is flat relative to the surface of the substrate, but it is not limited to this. The surface of the optoelectronic structure unit may be convex or concave relative to the surface of the substrate.

[0080] In the embodiment of the present application, the optoelectronic structure unit can produce a photoelectric effect for light of a specific frequency. The structure of the optoelectronic structure unit is described below.

[0081] In some optional embodiments, reference Figure 6 , the optoelectronic structure unit 42 includes:

[0082] a semiconductor layer 421, wherein the semiconductor layer 421 covers the substrate 41; and

[0083] The metal layer 422 covers the semiconductor layer 421 .

[0084] In the embodiment of the present application, the semiconductor layer undergoes a photoelectric effect under the irradiation of light, causing the electrons in the semiconductor layer to be excited to become free electrons. Due to the formation of a Schottky barrier between the semiconductor layer and the metal layer, the free electrons in the semiconductor layer will gather in the metal layer, leaving free holes in the semiconductor layer.

[0085] As an example, see Figure 7 , the holes in the semiconductor layer form positive charges, and the electrons in the metal layer form negative charges. It should be noted that the semiconductor layer is an n-type semiconductor layer, and a Schottky barrier is formed between the n-type semiconductor layer and the metal layer, which is equivalent to a Schottky diode model.

[0086] It should be noted that with the increase of positive charge in the semiconductor layer and the increase of negative charge in the metal layer, the electronic polarization effect will be enhanced, and the dielectric properties of the optoelectronic structure unit will change (reflected in the change of dielectric constant). According to the impedance calculation formula and the reflection loss calculation formula, it can be seen that the change of dielectric properties will lead to the change of reflectivity.

[0087] The impedance calculation formula is:

[0088] Among them, Z in represents the input impedance, Z0 represents the free space impedance, ε r represents the complex dielectric constant, μ r represents complex magnetic permeability, c represents the speed of light, f represents the frequency of electromagnetic waves, and t represents the thickness of the material.

[0089] According to the above impedance calculation formula, ε r The change will inevitably lead to Z in changes.

[0090] Reflection loss calculation formula:

[0091] Where RL represents the reflection loss.

[0092] According to the above reflection loss calculation formula, Z in The difference from Z0 will inevitably cause reflection loss, Z in The change of will inevitably cause the change of reflectivity.

[0093] In the embodiment of the present application, since the semiconductor layer in the optoelectronic structure unit needs to be irradiated by light to excite free electrons, the metal layer and substrate in contact with the semiconductor layer need to be transparent. Specifically, the substrate is a transparent substrate (also referred to as a transparent medium substrate), and the metal layer in the optical structure unit is a transparent metal layer. In addition, since the metal layer and the substrate are both transparent, the reflective panel is transparent as a whole, and free electrons can be excited regardless of whether the light is incident from the front or back of the reflective panel.

[0094] In some optional embodiments, such as Figure 7 As shown, light can be irradiated onto the reflective panel from the front side, and the light can be irradiated onto the semiconductor layer through the transparent metal layer, thereby exciting free electrons.

[0095] In some optional embodiments, such as Figure 8 As shown, light can be irradiated onto the reflective panel from the back, and the light can be irradiated onto the semiconductor layer through the transparent substrate, thereby exciting free electrons.

[0096] In some optional embodiments, such as Fig. 9 As shown, light can be irradiated onto the reflective panel from both the front and back sides simultaneously. The light from the front side irradiates the semiconductor layer through the transparent metal layer, and the light from the back side irradiates the semiconductor layer through the transparent substrate, thereby exciting free electrons.

[0097] As an optional implementation, the semiconductor layer in the photovoltaic structure unit can be a doped zinc oxide film. The metal layer in the photovoltaic structure unit can be a silver nanowire film. It can be understood that the photovoltaic structure unit is a composite film composed of a doped zinc oxide film and a silver nanowire film.

[0098] However, it is not limited thereto. The semiconductor layer in the optoelectronic structure unit may also be made of other types of materials with optoelectronic properties, and the metal layer in the optoelectronic structure unit may also be made of other types of materials with conductive properties.

[0099] As an optional implementation, the substrate can be made of quartz glass or a high molecular polymer. Further, the high molecular polymer can be, for example, polystyrene, or polycarbonate, or epoxy resin, or styrene acrylonitrile copolymer, etc.

[0100] Fig.10 Schematic diagram of a reflective panel, the substrate of the reflective panel is a transparent substrate, and the optoelectronic structural unit in the reflective panel is a composite film composed of a doped zinc oxide film and a silver nanowire film. Fig.10 For example, the shape of the optoelectronic structure unit is composed of two C-shaped structures, one large and one small, nested together. However, it is not limited to this, and the shape of the optoelectronic structure unit can also be other shapes, such as Z-shaped, I-shaped, etc. The technical solution of the embodiment of the present application does not limit the shape of the optoelectronic structure unit.

[0101] The reflective panel provided by the above-mentioned technical solution of the embodiment of the present application realizes the regulation of electromagnetic performance based on the photoelectric effect. Compared with the electrically-controlled intelligent reflective surface, the electronic components are replaced by the photoelectric structural unit that has light response to a specific frequency, thereby realizing the use of light control instead of electric control, eliminating the feeding line on the reflective panel.

[0102] The reflective panel provided by the above technical solution of the embodiment of the present application can adjust the electromagnetic properties of the reflective panel by illumination of a specific frequency, thereby achieving effective control of electromagnetic waves and improving the wireless channel environment. In addition, the substrate of the reflective panel can be a transparent substrate, and the metal layer in the optoelectronic structure unit can be a transparent metal layer, so that the light will not be strongly weakened before passing through the transparent substrate or the metal layer to reach the semiconductor layer, thereby achieving that the light source can meet the requirements regardless of whether it is incident from the front or the back. Furthermore, when the material of the reflective panel is all or mostly transparent, the entire reflective panel can be applied to specific scenarios, such as installing such a transparent reflective panel on the glass wall of a high-rise building or on the glass of a car.

[0103] In the actual process, all areas on the reflective panel can be illuminated with light of the same frequency and intensity, so that the optoelectronic structural units in all areas can present the same electromagnetic characteristics, thereby presenting the same reflectivity. Alternatively, different areas on the reflective panel can be illuminated with light of different frequencies and intensities, so that the optoelectronic structural units in different areas can present different electromagnetic characteristics, thereby presenting different reflectivities. In particular, when the size of the area with adjustable reflectivity is smaller than the electromagnetic wave frequency band, a series of complex manipulations including directional reflection and beamforming can be achieved on the electromagnetic wave. Through the transparent intelligent reflective panel based on light control response, not only does it not require a complex feeding network, it reduces the difficulty of designing the reflective panel, and the transparent optical properties also make it easier to apply to a variety of environments. The light source will not be attenuated regardless of front or back illumination, affecting the regulation function; in addition, by selecting optoelectronic materials with different limit frequencies to prepare the reflective panel, the reflective panel can only respond to light sources of specific frequencies, thereby avoiding the influence of natural light and other light sources on the regulation of the reflective arc panel.

[0104] Fig.11The process diagram of the method for preparing the reflective panel provided in the embodiment of the present application is as follows Figure 1 ,like Fig.11 As shown, the method for preparing the reflective panel includes the following steps:

[0105] Step 1101: Obtain a substrate.

[0106] In the embodiment of the present application,

[0107] In some optional embodiments of the present application, the substrate is a transparent substrate.

[0108] As an example, the substrate can be made of quartz glass or a polymer. Further, the polymer can be, for example, polystyrene, or polycarbonate, or a styrene acrylonitrile copolymer. It should be noted that the subsequent preparation process involves annealing of the substrate, so for a substrate made of a polymer, the polymer needs to be able to withstand the annealing temperature (for example, an annealing temperature of 350° C.) to ensure that it will not decompose or deform during the annealing process.

[0109] Step 1102: Carve a plurality of groove structures on the substrate.

[0110] In some optional embodiments of the present application, before engraving the plurality of groove structures on the substrate, a mask is covered on the substrate; then, the plurality of groove structures are engraved on the substrate covered with the mask. Here, the mask may be an organic coating.

[0111] For example: a layer of organic coating is applied to the surface of a transparent substrate, and then, based on the pattern of the optoelectronic structural unit (also called a metamaterial structural unit) obtained by simulation software, a groove structure corresponding to the optoelectronic structural unit is engraved on the substrate using precision machining.

[0112] In some optional embodiments of the present application, after the plurality of groove structures are engraved on the substrate covered with the mask, the substrate with the plurality of groove structures is placed in an acidic solution and cleaned by ultrasound.

[0113] Here, since excess residue will be left on the substrate when processing the groove structure, the substrate needs to be cleaned; in addition, since some thin films need to be sprayed in the grooves later to form optoelectronic structural units, in order to enhance the ability of the groove surface to adhere to the thin film, the groove surface needs to be modified.

[0114] For example, a transparent substrate with a groove structure is placed in an acidic solution and cleaned using ultrasound for a period of time, such as 5-30 minutes, to complete the surface modification and cleaning process.

[0115] Step 1103: manufacturing a plurality of photoelectric structure units in the plurality of groove structures to obtain a reflective panel; wherein each of the plurality of photoelectric structure units can generate a photoelectric effect for light of a specific frequency.

[0116] In the embodiment of the present application, the optoelectronic structure unit includes a semiconductor layer and a metal layer, and the optoelectronic structure unit can be manufactured in the following manner.

[0117] 1) Prepare semiconductor dispersion and metal dispersion.

[0118] In some optional embodiments of the present application, the semiconductor layer is a doped zinc oxide film, and a doped zinc oxide dispersion for realizing the doped zinc oxide film is prepared by the following method: I) pouring doping substances of zinc salt and metal salt into an aqueous solution, adding a coupling agent and stirring and mixing to obtain a precursor; II) preparing the precursor into a doped zinc oxide powder by a solvothermal method; III) dispersing the doped zinc oxide powder in an aqueous solution to obtain a doped zinc oxide dispersion.

[0119] For example: Pour the doping materials of zinc salt and metal salt into an aqueous solution, add appropriate amounts of coupling agents in succession and stir and mix under stirring conditions in a water bath to obtain a precursor, put the precursor into a high-pressure reactor, use a solvothermal method to react to prepare doped zinc oxide powder, and configure it into an aqueous phase mixed liquid (i.e., doped zinc oxide dispersion) for standby use.

[0120] In some optional embodiments of the present application, the metal layer is a silver nanowire film, and a silver nanowire dispersion for realizing the silver nanowire film is prepared by the following method: dispersing the silver nanowires in an aqueous solution to obtain a silver nanowire dispersion.

[0121] 2) spraying the semiconductor dispersion and the metal dispersion in sequence on the substrate with the multiple groove structures; wherein the semiconductor dispersion forms a semiconductor layer after air-drying, and the metal dispersion forms a metal layer after air-drying, the semiconductor layer covers the substrate, and the metal layer covers the semiconductor layer; the semiconductor layer and the metal layer in each of the multiple groove structures form a photoelectric structure unit, and multiple photoelectric structure units are formed in the multiple groove structures.

[0122] In some optional embodiments of the present application, the semiconductor layer is a doped zinc oxide film, which is prepared by a doped zinc oxide dispersion, and the metal layer is a silver nanowire film, which is prepared by a silver nanowire dispersion.

[0123] For example: the doped zinc oxide dispersion is evenly sprayed onto a transparent substrate with a groove structure, and naturally air-dried to form a doped zinc oxide film. This process can be repeated multiple times depending on the thickness requirements of the doped zinc oxide film; then, on this basis, the silver nanowire dispersion is continued to be evenly sprayed and naturally air-dried to form a silver nanowire film.

[0124] Since a composite film (ie, a photoelectric structural unit) composed of a doped zinc oxide film and a silver nanowire film is formed in each groove structure, a plurality of photoelectric structural units are formed in the plurality of groove structures.

[0125] In addition, in the process of manufacturing the above-mentioned photovoltaic structure unit, in addition to forming a thin film in the groove structure of the substrate, an excess thin film is also formed in other areas outside the groove structure of the substrate. In order to remove the excess thin film, after the photovoltaic structure unit is manufactured, the substrate is annealed to decompose the mask on the surface of the substrate, thereby achieving the purpose of removing the excess thin film. Specifically, the sprayed substrate can be placed in a muffle furnace for annealing to thermally decompose the organic coating on the surface of the substrate.

[0126] The reflective panel prepared by the above technical solution of the embodiment of the present application is an intelligent reflective panel based on light-controlled response. Compared with the electrically controlled reflective panel, since the adjustable electronic device is replaced by the optoelectronic structural unit, there is no need for power feeding. In addition, the material of the reflective panel can be made of a material with high light transmittance, so that on the basis of ensuring the high light transmittance of the reflective panel, the reflective performance of the reflective panel can be intelligently controlled by combining the optoelectronic effect of the optoelectronic structural unit.

[0127] Fig.12 The process diagram of the method for preparing the reflective panel provided in the embodiment of the present application is as follows Figure 2 ,like Fig.12 As shown, the method for preparing the reflective panel includes the following steps:

[0128] Step 1201: Covering a layer of organic coating on the surface of the transparent substrate.

[0129] In an application example, quartz glass can be selected as the transparent substrate, and E51 epoxy resin and W93 curing agent are evenly mixed in a mass ratio of 10:1. Then, the spray gun pressure is set to 0.5MPa, the distance is 10cm, and the moving speed is 1cm / s to spray onto the quartz glass surface. Then, it is dried in an oven at 60°C for 12 hours for curing to achieve coverage with the organic coating.

[0130] Step 1202: According to the pattern of the optoelectronic structure unit obtained by the simulation software, a groove structure is engraved based on the pattern by precision machining.

[0131] Here, the pattern of the optoelectronic structural unit can be designed using simulation software, and then the pattern data can be transmitted to a fine processing machine tool, which processes a groove structure on the surface of a transparent substrate covered with an organic coating according to the pattern data.

[0132] Step 1203: Perform surface modification and cleaning treatment on the transparent substrate.

[0133] Specifically, the transparent substrate is placed in an acidic solution and cleaned using ultrasound for a period of time, such as 5-30 minutes.

[0134] In an application example, taking quartz glass as a transparent substrate, the quartz glass is ultrasonically cleaned in a hydrogen peroxide / sulfuric acid mixture configured in a volume ratio of 2:1 for 5 minutes to complete the surface modification of the etched glass grooves to achieve the transformation from lipophilicity to hydrophilicity. It is then placed in an acetone solution, ultrasonically cleaned for 15 minutes, and then taken out and dried in a vacuum drying oven at 40°C.

[0135] Step 1204: spray coating using the doped zinc oxide dispersion and the silver nanowire dispersion.

[0136] Specifically, 1) the doping substances of zinc salt and metal salt are poured into an aqueous solution, and under the condition of stirring in a water bath, an appropriate amount of coupling agent is added successively for stirring and mixing to obtain a precursor, and the precursor is placed in a high-pressure reactor, and a doped zinc oxide powder is prepared by a solvent thermal method, and an aqueous phase mixed liquid (i.e., a doped zinc oxide dispersion) is configured for standby use. 2) The doped zinc oxide dispersion is evenly sprayed onto the transparent substrate obtained in the above steps by spraying, and naturally dried to form a doped zinc oxide film. This process can be repeated multiple times according to the requirements of the thickness of the doped zinc oxide film; 3) Silver nanowires are dispersed in an aqueous solution to form a silver nanowire dispersion, and the silver nanowire dispersion is continuously sprayed on the doped zinc oxide film by a spray gun, and naturally dried to form a silver nanowire film.

[0137] In an application example, 1) 0.2 g of aluminum nitrate nonahydrate and 1.28 g of zinc acetate dihydrate powder are weighed and poured into 80 ml of methanol solution, and then placed in a water bath at 70° C. for magnetic stirring, and then sodium hydroxide is added to adjust the pH value of the mixed solution to 9, and then 0.35 g of a coupling agent is added and continued to be stirred for 3 hours, and the uniformly stirred mixed solution is placed in a 100 ml high-pressure reactor, and after being kept warm at 150° C. for 6 hours by a solvothermal method, a precipitate (i.e., aluminum-doped zinc oxide powder) is obtained by reaction combined with high-speed centrifugation, and redispersed in water to prepare a dispersion with a concentration of 1 g / ml for standby use. 2) The aluminum-doped zinc oxide dispersion prepared in the above process is loaded into a spray gun, and the spray gun pressure is set to 0.8 MPa, the distance is 12 cm, and the moving speed is 0.5 cm / s for spraying, and then it is naturally air-dried until a thin film is formed. Here, the operation can be repeated multiple times according to the actual thickness requirements of the aluminum-doped zinc oxide; 3) Silver nanowires with a diameter of less than 20 nanometers and an aspect ratio of greater than 500 are dispersed in a methanol solution at a concentration of 0.5 g / ml, and then put into a spray gun, and the spray gun pressure is set to 0.5 MPa, the distance is 10 cm, and the moving speed is 0.5 cm / s for spraying, and then it is naturally air-dried until a thin film is formed.

[0138] Step 1205: placing the coated transparent substrate in a muffle furnace for annealing treatment to thermally decompose the organic coating on the surface of the transparent substrate to obtain a light-controlled transparent intelligent reflective panel.

[0139] In an application example, the transparent substrate that has been coated obtained by the above process is placed in a muffle furnace, heated to 350°C, and kept warm for 4 hours to ensure that the organic coating on the substrate (i.e., organic matter with a thermal decomposition temperature below 350°C, such as epoxy resin) can be decomposed by heat, thereby obtaining a transparent reflective panel that responds to light.

[0140] In the above technical solution of the embodiment of the present application, in an application example, the doped zinc oxide film can be an aluminum-doped zinc oxide film, and a transparent aluminum-doped zinc oxide photoelectric film and a silver nanowire film are used to construct a Schottky contact. Under illumination conditions, the aluminum-doped zinc oxide film will generate free electrons due to the photoelectric effect. Under the action of the Schottky barrier, directional movement occurs, and the electron polarization moves frequently, and the dielectric properties change accordingly, further affecting the reflection performance. In other words, under the action of the photoelectric effect induced by light, the reflective panel can achieve a change in reflective performance. Since the limit frequency of the aluminum-doped zinc oxide film is in the ultraviolet light band, it has a photoelectric response to light waves with frequencies in the ultraviolet light band and above. The polarization loss is increased by the directional movement of free electrons, so that the reflectivity of the illuminated reflective plate can be changed. By irradiating different areas of the reflective panel with light waves of different light intensities and frequencies, the reflective performance of the reflective panel can be intelligently controlled.

[0141] The smart reflective panel provided in the embodiment of the present application has the characteristics of high light transmittance and light control, and thus has broad application prospects in future communication development and improvement of wireless channel environment.

[0142] It should be understood that the "in an embodiment of the present application" or "in some embodiments" mentioned throughout the specification means that specific features, structures or characteristics related to the embodiment are included in at least one embodiment of the present application. Therefore, "in an embodiment of the present application" or "in some embodiments" appearing throughout the specification may not necessarily refer to the same embodiment. In addition, these specific features, structures or characteristics can be combined in one or more embodiments in any suitable manner. It should be understood that in various embodiments of the present application, the size of the sequence number of the above-mentioned processes does not mean the order of execution, and the execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiment of the present application. The above-mentioned sequence numbers of the embodiments of the present application are for description only and do not represent the advantages and disadvantages of the embodiments.

[0143] The methods disclosed in several method embodiments provided in this application can be arbitrarily combined without conflict to obtain new method embodiments.

[0144] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A reflective panel, characterized in that: The reflective panel comprises: substrate; and, A plurality of optoelectronic structural units located on the substrate, each of the plurality of optoelectronic structural units being capable of generating a photoelectric effect for light of a specific frequency; When light of a specific frequency irradiates the reflective panel, the photoelectric effect generated by the plurality of photoelectric structural units causes the electromagnetic properties of the reflective panel to change; The photovoltaic structure unit comprises: a semiconductor layer, the semiconductor layer covering the substrate; and A metal layer covers the semiconductor layer.

2. The reflective panel according to claim 1, characterized in that: The substrate has a plurality of groove structures, and the plurality of groove structures correspond to the plurality of optoelectronic structure units one by one, wherein one optoelectronic structure unit is located in one groove structure.

3. The reflective panel according to claim 1, characterized in that: The semiconductor layer is a doped zinc oxide film.

4. The reflective panel according to claim 1, characterized in that: The metal layer is a silver nanowire film.

5. The reflective panel according to any one of claims 1 to 4, characterized in that: The metal layer is a transparent metal layer.

6. The reflective panel according to any one of claims 1 to 4, characterized in that: The substrate is a transparent substrate.

7. The reflective panel according to any one of claims 1 to 4, characterized in that: The plurality of optoelectronic structure units are periodically distributed on the substrate.

8. A method for preparing a reflective panel, characterized in that: The method comprises: Obtaining a substrate; Carving a plurality of groove structures on the substrate; Manufacturing a plurality of optoelectronic structure units in the plurality of groove structures to obtain a reflective panel; Wherein, each of the plurality of optoelectronic structural units can produce a photoelectric effect for light of a specific frequency; Wherein, the optoelectronic structure unit comprises: a semiconductor layer, the semiconductor layer covering the substrate; and A metal layer covers the semiconductor layer.

9. The method according to claim 8, characterized in that Before carving a plurality of groove structures on the substrate, the method further comprises: covering the substrate with a mask; The step of carving a plurality of groove structures on the substrate comprises: carving a plurality of groove structures on a substrate covered with a mask.

10. The method according to claim 9, characterized in that After engraving a plurality of groove structures on the substrate covered with the mask, the method further comprises: The substrate with the plurality of groove structures is placed in an acid solution and cleaned by ultrasound.

11. The method according to claim 9, characterized in that The method of manufacturing a plurality of optoelectronic structure units in the plurality of groove structures comprises: Preparation of semiconductor dispersions and metal dispersions; Spraying the semiconductor dispersion liquid and the metal dispersion liquid sequentially on the substrate with the plurality of groove structures; Among them, the semiconductor dispersion forms a semiconductor layer after being air-dried, and the metal dispersion forms a metal layer after being air-dried, the semiconductor layer is covered on the substrate, and the metal layer is covered on the semiconductor layer; the semiconductor layer and the metal layer in each of the multiple groove structures form a photoelectric structure unit, and multiple photoelectric structure units are formed in the multiple groove structures.

12. The method according to claim 11, characterized in that The semiconductor layer is a doped zinc oxide film, and the preparation of the semiconductor dispersion comprises: Pour the doping material of zinc salt and metal salt into an aqueous solution, add a coupling agent, and stir and mix to obtain a precursor; The precursor is prepared into doped zinc oxide powder by a solvothermal method; The doped zinc oxide powder is dispersed in an aqueous solution to obtain a doped zinc oxide dispersion.

13. The method according to claim 11, characterized in that The metal layer is a silver nanowire film, and the metal dispersion is prepared, comprising: The silver nanowires are dispersed in an aqueous solution to obtain a silver nanowire dispersion.

14. The method according to any one of claims 9 to 13, characterized in that After a plurality of optoelectronic structure units are fabricated in the plurality of groove structures, the method further comprises: The substrate with the plurality of optoelectronic structure units is subjected to an annealing treatment so that the mask on the surface of the substrate is decomposed.

15. The method according to any one of claims 8 to 13, characterized in that The substrate is a transparent substrate.

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