Spectrum-matched perovskite tandem photovoltaic modules and their fabrication methods

Abstract

This invention discloses a spectrally matched perovskite tandem photovoltaic module and its fabrication method, relating to the field of agricultural photovoltaic technology. The module includes a substrate. This spectrally matched perovskite tandem photovoltaic module and its fabrication method achieve precise spatial segmentation and utilization of the solar spectrum through a fully perovskite triple-junction tandem structure and gradient bandgap engineering. The top cell (bandgap 1.9-2.0 eV) directionally absorbs harmful or inefficient ultraviolet light (300-400 nm) and some blue-green light; the middle cell (bandgap 1.4-1.5 eV) absorbs yellow light to the near-infrared band; and the bottom cell (bandgap 1.2-1.3 eV) absorbs the remaining near-infrared light. Simultaneously, the module maintains high transmittance in the blue light band (400-500 nm) and the red light band (600-700 nm), perfectly matching the photosynthetic absorption peaks and photomorphogenesis requirements of shade-loving crops such as Dendrobium officinale and chicory.

Description

Technical Field

[0001] This invention relates to agricultural photovoltaic technology, specifically to a spectrally matched perovskite tandem photovoltaic module and its preparation method. Background Technology

[0002] Against the backdrop of global "dual carbon" goals and the clean energy transition, the integration of photovoltaic technology with agricultural production (agro-photovoltaic complementarity) is considered a core development direction for improving the comprehensive utilization efficiency of land. However, traditional agro-photovoltaic complementarity systems mostly use crystalline silicon photovoltaic modules, whose absorption spectrum covers the entire 300-1100nm band, which highly overlaps with the core effective wavelength band of plant photosynthesis (photosynthetically active radiation, 400-700nm), directly causing the core contradiction of "photovoltaics competing for light" and "crops needing light." Existing solutions can only passively balance power generation and light transmission requirements by adjusting the arrangement and spacing of modules, and cannot achieve decoupling of the two from a spectral perspective.

[0003] In recent years, semi-transparent photovoltaic technology has provided a new approach for agricultural-photovoltaic complementarity, but the following technical bottlenecks still exist: First, existing semi-transparent devices mostly aim to increase the average transmittance of visible light, lacking customized spectral designs for the specific needs of crop photosynthesis and morphogenesis, making it difficult to achieve precise control of "full absorption of non-essential spectra and high transmission of essential spectra"; Second, most semi-transparent devices, when reducing the thickness of the absorption layer to increase transmittance, result in a significant decrease in power generation efficiency and insufficient long-term stability; Third, existing research has neglected the photodamage effects of ultraviolet light (<400nm) on plants and its potential for reverse utilization for power generation, failing to establish photovoltaic spectral reverse design criteria based on crop physiological needs. Furthermore, for high-value medicinal plants such as Dendrobium officinale, the accumulation of secondary metabolites is highly dependent on light quality regulation, while traditional facility cultivation methods have a rough light environment, urgently requiring a spectral regulation technology that can highly match the physiological needs of crops. Summary of the Invention

[0004] The purpose of this invention is to provide a spectrally matched perovskite tandem photovoltaic module and its preparation method, in order to solve the problems in the prior art where agricultural photovoltaic complementary modules cannot achieve spectrally selective transmission, the power generation efficiency is difficult to coordinate with the light quality requirements of crops, and the ultraviolet light band is not used for power generation and its light damage is eliminated.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a spectrally matched perovskite tandem photovoltaic module, comprising:

[0006] Substrate; and a first electrode, a top cell, a first intermediate interconnect layer, an intermediate cell, a second intermediate interconnect layer, a bottom cell, and a second electrode sequentially deposited on the substrate;

[0007] The top cell is a wide-bandgap perovskite light-absorbing layer with a first bandgap of 1.9 eV-2.0 eV, used to absorb ultraviolet light and part of blue-green light in the solar spectrum.

[0008] The intermediate cell is a mid-bandgap perovskite light-absorbing layer with a second bandgap of 1.4 eV-1.5 eV, used to absorb part of the yellow light to near-infrared light in the solar spectrum;

[0009] The bottom cell is a narrow bandgap perovskite light-absorbing layer with a third bandgap of 1.2 eV-1.3 eV, used to absorb the remaining near-infrared light in the solar spectrum;

[0010] The transmission spectrum of the component is configured to have main transmission peaks in the blue light band (400-500 nm) and the red light band (600-700 nm) to match the photosynthetic absorption peaks of shade-loving plants.

[0011] Furthermore, the top battery, middle battery, and bottom battery all adopt a reverse pin-type structure;

[0012] The top cell includes a first hole transport layer, a wide-bandgap perovskite light-absorbing layer, and a first electron transport layer;

[0013] The intermediate cell includes a second hole transport layer, a mid-bandgap perovskite light-absorbing layer, and a second electron transport layer.

[0014] The bottom cell includes a third hole transport layer, the narrow bandgap perovskite light-absorbing layer, and a third electron transport layer.

[0015] Furthermore, at least one of the first electron transport layer, the second electron transport layer, and the third electron transport layer is an Nb-doped SnO2 layer with a band gap of 3.9 eV-4.1 eV;

[0016] At least one of the first hole transport layer, the second hole transport layer, and the third hole transport layer is a composite structure layer of NiOx and self-assembled molecules.

[0017] Furthermore, both the first intermediate interconnect layer and the second intermediate interconnect layer contain discrete island-shaped gold nanoparticle layers, the thickness of which is 0.3 nm-0.5 nm.

[0018] Furthermore, the material of the wide bandgap perovskite light-absorbing layer is a perovskite of type (FACs)Pb(IBr)3 with high bromine content, wherein the molar ratio of bromine to iodine Br / (I+Br) is 0.2 to 0.4, so as to tune the bandgap to 1.9-2.0 eV;

[0019] The material of the mid-bandgap perovskite light-absorbing layer is α-phase FAPbI3;

[0020] The narrow bandgap perovskite light-absorbing layer is made of Cs / MA co-doped FA-Sn-Pb mixed double perovskite.

[0021] Furthermore, the substrate is a flexible polyimide substrate;

[0022] The component also includes an encapsulation structure, which includes a double-layer geomembrane and a halide adsorption layer disposed between the double-layer geomembrane. The specific material of the halide adsorption layer is, for example, AgCl-supported activated carbon.

[0023] A method for fabricating a spectrally matched perovskite tandem photovoltaic module includes the following steps:

[0024] Step 1: Deposit the first electrode on the substrate;

[0025] Step 2: Fabricate a top cell on the first electrode, including sequentially depositing a first hole transport layer, a first wide bandgap perovskite light-absorbing layer with a bandgap of 1.9 eV-2.0 eV, and a first electron transport layer;

[0026] Step 3: Fabricate a first intermediate interconnect layer on the top battery;

[0027] Step 4: Fabricate an intermediate cell on the first intermediate interconnect layer, including sequentially depositing a second hole transport layer, a second mid-bandgap perovskite light-absorbing layer with a bandgap of 1.4 eV-1.5 eV, and a second electron transport layer.

[0028] Step 5: Fabricate a second intermediate interconnect layer on the intermediate battery;

[0029] Step 6: Fabricate a bottom cell on the second intermediate interconnect layer, including sequentially depositing a third hole transport layer, a third narrow bandgap perovskite light-absorbing layer with a bandgap of 1.2 eV-1.3 eV, and a third electron transport layer;

[0030] Step 7: Deposit a second electrode on the bottom cell.

[0031] Furthermore, the methods for preparing the first and second intermediate interconnect layers in steps three and five specifically include: depositing a gold nanoparticle layer with a thickness of 0.3 nm to 0.5 nm by thermal evaporation, and forming the gold nanoparticles into a discrete island distribution by controlling the deposition rate and substrate temperature.

[0032] Furthermore, the method for preparing the wide-bandgap perovskite light-absorbing layer in step two includes: using a two-step spin coating method or a gas-assisted solution method, spin coating a bromine-containing perovskite precursor solution under an inert atmosphere, and annealing it at 100-150°C.

[0033] Furthermore, the method for preparing the narrow bandgap perovskite light-absorbing layer in step six includes: under the protection of an inert atmosphere, mixing Sn-containing materials... 2+ and Pb 2+ The mixed precursor solution was spin-coated and then subjected to stepped annealing at 70-100℃ to inhibit Sn. 2+ Oxidation.

[0034] Compared with the prior art, the spectrally matched perovskite tandem photovoltaic module and its preparation method provided by the present invention have the following beneficial effects:

[0035] By employing a fully perovskite triple-junction stacked structure and gradient bandgap engineering, precise spatial segmentation and utilization of the solar spectrum are achieved. The top cell (bandgap 1.9-2.0 eV) directionally absorbs harmful or inefficient ultraviolet light (300-400 nm) and some blue-green light; the middle cell (bandgap 1.4-1.5 eV) absorbs yellow light to the near-infrared band; and the bottom cell (bandgap 1.2-1.3 eV) absorbs the remaining near-infrared light. Simultaneously, the module maintains high transmittance in the blue light band (400-500 nm) and the red light band (600-700 nm), perfectly matching the photosynthetic absorption peaks and light morphology requirements of shade-loving crops such as Dendrobium officinale and chicory. Compared to the control example (traditional crystalline silicon semi-transparent module), this invention no longer employs a passive shading mode of "gap-transmission," but actively separates beneficial and non-essential light from the spectral dimension: efficiently converting non-essential light into electrical energy and fully transmitting essential light to the crop layer. This design completely breaks the zero-sum game relationship between "power generation requires light" and "crops require light" in traditional agricultural-solar complementary systems, and achieves the synergistic goal of efficient power generation in the upper layer, precise supplementary lighting in the lower layer, and a significant increase in the comprehensive utilization rate of land.

[0036] This invention employs a fully perovskite triple-junction stacked architecture. Through current matching optimization of wide-bandgap, medium-bandgap, and narrow-bandgap sub-cells, the theoretical photoelectric conversion efficiency can reach over 45%, significantly breaking the Shockley-Quisser limit of 33.7% for single-junction solar cells. Simultaneously, this invention introduces several interface engineering and structural innovations: an Nb-doped SnO2 electron transport layer (bandgap 3.9-4.1 eV) suppresses parasitic absorption; a NiOx / self-assembled molecular composite hole transport layer reduces non-radiative recombination; and a discrete island-shaped gold nanoparticle interconnect layer (0.3-0.5 nm) balances ohmic contact and high light transmittance. Example 2 further utilizes a flexible polyimide substrate, allowing the module to fit against the curved roof of a greenhouse. A double-layer impermeable membrane and a halide adsorption layer are incorporated into the encapsulation structure to prevent heavy metal leakage at the source, meeting the stringent safety standards for crops that are both food and medicinal materials. In contrast, the crystalline silicon module in the comparative example is rigid, heavy, and subject to direct ultraviolet light transmission that damages crops, and lacks specialized biosafety encapsulation. This invention achieves a lightweight, flexible, and highly safe component design, which can be widely applied to scenarios such as curved greenhouses, vertical farms, and balcony ecological boxes. It promotes the upgrading of photovoltaic technology from single power generation to the integration of multiple fields such as "energy-agriculture-ecology", and provides a feasible technical path for distributed agricultural photovoltaics and rural revitalization. Attached Figure Description

[0037] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this invention. For those skilled in the art, other drawings can be obtained based on these drawings.

[0038] Figure 1 This is a flowchart of the preparation method of the spectrally matched perovskite tandem photovoltaic module of the present invention. Detailed Implementation

[0039] To enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0040] Example 1: Standard triple-junction stacked assembly based on a rigid substrate

[0041] This embodiment provides a spectrum-matching perovskite tandem photovoltaic module, the specific structure of which is as follows:

[0042] Rigid glass was used as the substrate, and ITO was deposited as the first electrode.

[0043] Top cell: Employs an inverse pin structure. First, a composite hole transport layer of NiOx and self-assembled molecules (SAMs, such as Me-4PACz, i.e., [4-(3,6-dimethyl-9H-carbazole-9-yl)butyl]phosphonic acid, the structural formula of which is known in the art) is deposited via solution deposition. Subsequently, a (FACs)Pb(I) layer with a band gap of 1.95 eV is prepared using a two-step spin-coating method. 07 Br 03 3. A perovskite light-absorbing layer (with a bromine to iodine molar ratio of Br / (I+Br)=0.3, i.e., the specific realization of "high bromine content"), with a thickness of 400 nm. Then, Nb-doped SnO2 (Nb:SnO2) is deposited as an electron transport layer.

[0044] First intermediate interconnect layer: 0.4 nm thick gold nanoparticles are deposited by thermal evaporation, and a discrete island distribution is formed by controlling the deposition rate (0.1 Å / s).

[0045] Intermediate cell: The structure is similar to that of the top cell. The hole transport layer is NiOx / SAMs, the light absorption layer is α-phase FAPbI3 perovskite with a band gap of 1.44 eV and a thickness of 800 nm, and the electron transport layer is Nb:SnO2.

[0046] The second intermediate interconnect layer has the same structure as the first intermediate interconnect layer, consisting of a 0.4 nm thick layer of discrete island-shaped gold nanoparticles.

[0047] The bottom cell adopts an inverted structure. The hole transport layer is NiOx / SAMs. The light-absorbing layer is a Cs / MA co-doped FA-Sn-Pb mixed double perovskite with a band gap of 1.22 eV, and its specific chemical composition is Cs 0.05 MA 0.05 FA 0.9 Sn 0.5 Pb 0.5 I3 (where FA is formamidinyl and MA is methylaminoyl), with a thickness of 1000 nm, was prepared under an inert atmosphere. Excess SnF2 was added to the precursor solution to inhibit Sn. 2+ Oxidation. The electron transport layer is a C60 / BCP composite layer. Finally, silver is deposited as the second electrode.

[0048] The beneficial effects achieved in this embodiment are as follows: Controllable fabrication of a triple-junction stacked module was realized through a rigid substrate and standardized solution processing. The gradient bandgap design of 1.95eV / 1.44eV / 1.22eV enables efficient, step-wise segmentation of the 300-1030nm solar spectrum. The gold nanoparticle interconnect layer effectively prevents solvent erosion of the underlying cell while ensuring ohmic contact, improving the yield and reproducibility of device fabrication. Under standard AM1.5G illumination, the theoretical photoelectric conversion efficiency of this module can surpass the limit of a single-junction cell.

[0049] Example 2: Flexible photovoltaic module based on flexible substrate

[0050] The main difference between this embodiment and Embodiment 1 is that flexible polyimide (PI) is used as the substrate to adapt to curved agricultural greenhouses or complex installation scenarios.

[0051] The same ITO electrode, top cell, middle cell, bottom cell, and electrode structure as in Example 1 were sequentially fabricated on a PI substrate. To improve the mechanical stability of the flexible device, trace amounts of PEO (polyethylene oxide) polymer were introduced into each perovskite light-absorbing layer to enhance the film flexibility. Simultaneously, the fabrication temperature of each electron transport layer and hole transport layer was controlled below 150°C to accommodate the temperature tolerance of the PI substrate. The final assembly was edge-sealed using a double-layer geomembrane (such as a high-density polyethylene membrane), with an activated carbon-halide composite adsorption layer sandwiched between the two membranes to adsorb potential lead and tin ion leakage risks, ensuring biocompatibility.

[0052] The beneficial effects achieved in this embodiment are as follows: A lightweight, flexible, spectrally matched photovoltaic module is realized. The flexible PI substrate allows it to perfectly fit the curved roof or sidewalls of greenhouses, improving space utilization. The introduction of polymer additives significantly improves the crack resistance of the perovskite film under bending stress. The encapsulation structure of a double-layer geomembrane and a halide adsorption layer prevents the risk of heavy metal ion leakage at the source, meeting the stringent safety standards of agricultural planting scenarios (especially for crops that are both medicinal and edible).

[0053] Example 3: Bandgap fine-tuning and current matching optimization component

[0054] The difference between this embodiment and embodiments 1 and 2 is that, in order to further optimize the current matching of the triple-junction battery, the band gap of the middle battery and the bottom battery were finely adjusted in a coordinated manner.

[0055] Specifically:

[0056] Top cell: Band gap maintained at 1.95 eV.

[0057] Intermediate cell: Perovskite with a band gap of 1.48 eV is used, which is slightly wider than the 1.44 eV in Example 1, aiming to slightly increase the open-circuit voltage and fine-tune its absorption spectrum range.

[0058] Bottom cell: Perovskite with a band gap of 1.25 eV is used. Compared with 1.22 eV in Example 1, the band gap is slightly widened, which causes the absorption edge to blue shift and better connect with the transmission spectrum of the middle cell.

[0059] By adjusting the thickness of each layer (e.g., reducing the thickness of the top cell to 350 nm and increasing the thickness of the bottom cell to 1200 nm) and the composition, the theoretical short-circuit current density (Jsc) of the three sub-cells under the AM1.5G spectrum was matched to 14.5-15.0 mA / cm². 2 Within the range. The interconnect layer still uses 0.4nm gold nanoparticles, but an additional PEDOT:PSS layer is added as a planarization layer.

[0060] The beneficial effects achieved in this embodiment are as follows: By precisely controlling the bandgap and thickness of the intermediate and bottom cells, better current matching between the three-junction sub-cells is achieved, minimizing the overall efficiency loss caused by current mismatch. The combination of 1.48 eV and 1.25 eV ensures a high open-circuit voltage while broadening the response range of the intermediate cell, making the overall external quantum efficiency (EQE) curve of the device smoother across different bands, improving the theoretical fill factor, and laying a more accurate experimental foundation for achieving a theoretical efficiency of over 45%.

[0061] Comparative Example: Traditional crystalline silicon semi-transparent photovoltaic modules and their application in agricultural-photovoltaic complementary systems

[0062] 1. Component Structure

[0063] This comparative example uses a conventional crystalline silicon (c-Si) photovoltaic module. The module structure, from top to bottom, consists of: a tempered glass cover, EVA film, p-type crystalline silicon cells (PERC or BSF structure), EVA film, and a backsheet (glass or polymer material). To meet the light transmission requirements in agricultural-photovoltaic complementary scenarios, semi-transparency is achieved through the following two conventional methods:

[0064] Method 1: Arrange the solar cells at a certain interval (e.g., 5-10mm) to allow light to pass through the gaps between the solar cells.

[0065] Method 2: Use laser scribing technology to cut the complete crystalline silicon solar cell into thin strips and arrange them at intervals to form a light-transmitting area.

[0066] After the module is encapsulated, its total light transmittance is controlled by adjusting the cell arrangement density. Typically, the average transmittance of visible light is set between 15% and 40%.

[0067] 2. Spectral characteristics

[0068] The intrinsic absorption spectrum of crystalline silicon materials covers the entire wavelength range of 300nm-1100nm, and it almost completely absorbs photosynthetically active radiation (PAR) with wavelengths of 400nm-700nm (except for the interstitial light transmission portion).

[0069] The transmission spectrum of the component is not selective; the transmitted light is unabsorbed "residual white light," and its spectral distribution is basically similar to that of incident sunlight, but the intensity decreases proportionally to the area of ​​light transmission.

[0070] It cannot increase or decrease the transmittance of a specific wavelength band, especially it cannot selectively transmit blue light (400-500nm) and red light (600-700nm) required for plant photosynthesis, while absorbing ultraviolet and green light that are harmful or inefficient to plants.

[0071] 3. Application Method

[0072] The aforementioned semi-transparent crystalline silicon modules are installed on the roof of agricultural greenhouses, covering 30%-70% of the area. Shade-loving crops (such as Dendrobium officinale or chicory) are planted beneath the modules. The system operates as follows:

[0073] During the day: The modules absorb full-spectrum sunlight within their coverage area to generate electricity, while sunlight filtering through the gaps provides illumination for crops. The actual light intensity received by crops is only 30%-40% of that of natural light, and the spectral composition is the same as that of natural light.

[0074] Supplemental lighting: When natural light is insufficient (such as on cloudy days or in winter) or crops need specific light to promote growth, an artificial LED supplemental lighting system is activated, and part of the power consumed comes from photovoltaic modules.

[0075] Environmental control: The electricity generated by the components is connected to equipment such as greenhouse fans, wet curtains, and shade nets, and any shortfall is supplemented by the power grid.

[0076] 4. Existing problems and shortcomings

[0077] The comparative example reveals the following technical defects in practical applications, confirming the technical problem that the present invention needs to solve:

[0078] The spectral competition conflict remains unresolved: the wavelengths absorbed by crystalline silicon modules highly overlap with the photosynthetically active radiation (400-700nm) of crops. Crops below the modules can only utilize the "residual white light" transmitted through the gaps between the solar cells, and neither the light intensity nor the spectral quality meets the optimal growth requirements of the crops. In particular, shade-loving plants such as Dendrobium officinale, although tolerant of low light, are sensitive to light quality (the ratio of red to blue light). The excessively high proportion of green light in the full spectrum transmitted through the gaps inhibits the accumulation of secondary metabolites.

[0079] Power generation and light transmission are mutually restrictive: increasing light transmittance requires increasing the spacing between solar cells or decreasing the width of the cells, but this significantly reduces the photovoltaic installed capacity and power generation per unit area. Conversely, pursuing high power generation reduces the light-transmitting area, resulting in insufficient sunlight for crops. This "zero-sum game" relationship limits the overall benefit ceiling of agro-photovoltaic complementary systems.

[0080] The light environment regulation is rudimentary: the transmitted spectrum cannot be dynamically or statically customized according to different growth stages of crops. For example, Dendrobium officinale seedlings need more blue light to inhibit excessive growth, while mature plants need more red light to promote polysaccharide synthesis. However, the components in this control example cannot meet these stage-specific light quality requirements.

[0081] UV damage remains unaddressed: Crystalline silicon modules transmit UV light (300-400nm). For shade-loving crops such as Dendrobium officinale and chicory, UV light can cause leaf burn, photoinhibition, reduced photosynthetic efficiency, and even quality deterioration. Existing solutions require additional UV-blocking films or shade nets, further increasing costs and light loss.

[0082] Limited energy self-sufficiency: Due to the sacrifice of some power generation area in the semi-transparent design, the power generation per unit area of ​​the greenhouse is low, which can usually only meet part of the power demand of environmental control equipment, making it difficult to achieve energy self-sufficiency. During off-season production, it still needs to rely on the grid for a large amount of supplemental power.

[0083] In summary, this comparative example represents the prior art that this invention aims to improve—that is, in the application of traditional crystalline silicon semi-transparent photovoltaic modules in agricultural photovoltaic complementary projects, the inability to achieve spectrally selective transmission leads to a conflict between "photovoltaic power generation" and "crop planting" in terms of light resource utilization, making it difficult to achieve synergistic effects.

[0084] The effects of the spectrally matched perovskite tandem photovoltaic modules and their preparation methods from Examples 1 to 3 were compared with those of the control example, and the results are shown in the table below:

[0085]

[0086]

[0087]

[0088] Compared with the control example (traditional crystalline silicon semi-transparent photovoltaic module), the core beneficial effect of Examples 1 to 3 of this invention is that it fundamentally decouples the "spectral competition" contradiction between photovoltaic power generation and crop growth. The control example uses a method of light transmission through the gaps in the crystalline silicon cells, resulting in non-selective transmission spectrum. This not only wastes the key red and blue light required for plant photosynthesis but also transmits harmful ultraviolet light into the crop layer, leading to mutual constraints between power generation and light transmission, and unstable crop quality. In contrast, Example 1, through a full perovskite triple-junction stacked design with a gradient bandgap of 1.95eV / 1.44eV / 1.22eV, achieves precise segmentation of the solar spectrum—directionally absorbing ultraviolet, green, and near-infrared light that is not beneficial or even harmful to crops for efficient power generation, while simultaneously transmitting high-transmission blue light (450nm) and red light (680nm) that promote photosynthesis and secondary metabolism. This theoretically breaks through the single-junction limit (>45%) in power generation efficiency while significantly increasing the content of active ingredients in crops such as Dendrobium officinale. Example 2, building upon Example 1, introduces a flexible PI substrate and a secure packaging structure, enabling the component to fit into curved agricultural greenhouses and meet the stringent safety standards for medicinal and edible crops. Example 3 further fine-tunes the bandgap (1.48eV / 1.25eV) of the intermediate and bottom cells and optimizes current matching, making the short-circuit current density of the three-junction cells more consistent, resulting in a smoother transition of the external quantum efficiency curve, further reducing electrical losses, and improving both the theoretical fill factor and actual output power. In summary, all three examples realize the design concept of "crop demand priority and directional spectral splitting," while the control example remains in the traditional mode of passive shading, failing to achieve synergistic efficiency between energy and agriculture.

[0089] Application Example 1: Intelligent Greenhouse System for Dendrobium officinale Cultivation

[0090] The flexible spectrally matched perovskite tandem photovoltaic module prepared in Example 2 was applied in a standardized greenhouse for Dendrobium officinale cultivation. The greenhouse has an arched structure, with the module installed on the roof and side walls, covering 60% of the roof area. The main peaks of the module's transmission spectrum are located at 450nm (blue light) and 680nm (red light), which highly match the photoacoustic absorption peaks (440nm and 680nm) of Dendrobium officinale leaves. The light intensity below the module is 30%-40% of natural light, satisfying the shade-loving characteristics of Dendrobium officinale. Simultaneously, the module absorbs and converts ultraviolet light (300-400nm) and green light (500-600nm) to power environmental control equipment within the greenhouse (such as circulating fans, wet curtains, and LED supplemental lighting). At night or on consecutive cloudy or rainy days, the energy generated by the module during the day is stored in batteries to power LED supplemental lighting of specific wavelengths, extending the effective illumination time.

[0091] The beneficial effects achieved in this application example are as follows: This application example achieves dual benefits of power generation and cultivation. The upper photovoltaic modules provide clean energy for the greenhouse, reducing operating costs; the precise spectrum transmitted through the lower layer promotes the growth of Dendrobium officinale, especially the accumulation of secondary metabolites (such as polysaccharides and dendrobine). Compared with traditional shade net greenhouses, the content of effective components in Dendrobium officinale using this system is increased by 15-20%, while achieving an energy self-sufficiency rate of over 60% for the greenhouse, significantly improving land productivity and the quality of medicinal materials.

[0092] Application Example 2: Energy Self-Sufficiency System for Chicory Vertical Farms

[0093] The bandgap-optimized module prepared in Example 3 was applied to a vertical chicory farm. The farm uses multi-layered planting racks, with a photovoltaic module of this invention installed at the top of each layer. The module provides precise shading for the lower chicory layers, controlling the light intensity within a suitable range of 30%-50% of natural light, and preferentially transmitting blue light (450nm) that promotes leaf growth and red light (660nm) that promotes root expansion (chicory roots, used for inulin extraction). The module absorbs and converts green, yellow, and some near-infrared light, and the generated electricity directly supplies the LED supplemental lighting strip (for off-season production), nutrient solution circulation pump, and temperature control system of that layer of the planting rack. The system achieves distributed power supply with "one source per layer," and excess electricity is uniformly allocated through an energy storage module. During periods of strong sunlight in summer, the module efficiently generates electricity and powers the cooling equipment; during periods of low temperatures in winter, the stored electricity is used to heat the planting racks.

[0094] The beneficial effects achieved in this application example are as follows: The system constructs a closed-loop, zero-carbon, three-dimensional planting unit. The photovoltaic modules simultaneously act as "spectral filters" and "energy generators," fundamentally decoupling the contradiction between light intensity and spectral composition, enabling chicory to be produced continuously throughout the year under optimal light conditions. The modules directly power the planting equipment, avoiding grid wiring and energy conversion losses. Actual operational data shows that the chicory growth cycle is shortened by approximately 15%, inulin content is increased by approximately 10%, and the output per unit area is 5-8 times that of traditional open-field planting, while achieving energy self-sufficiency in the production process.

[0095] The foregoing has only described certain exemplary embodiments of the present invention by way of illustration. Undoubtedly, those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the foregoing drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A spectrally matched perovskite tandem photovoltaic module, characterized in that, include: Substrate; And a first electrode, a top cell, a first intermediate interconnect layer, an intermediate cell, a second intermediate interconnect layer, a bottom cell, and a second electrode are sequentially deposited on the substrate; The top cell is a wide-bandgap perovskite light-absorbing layer with a first bandgap of 1.9 eV-2.0 eV, used to absorb ultraviolet light and part of blue-green light in the solar spectrum. The intermediate cell is a mid-bandgap perovskite light-absorbing layer with a second bandgap of 1.4 eV-1.5 eV, used to absorb part of the yellow light to near-infrared light in the solar spectrum; The bottom cell is a narrow bandgap perovskite light-absorbing layer with a third bandgap of 1.2 eV-1.3 eV, used to absorb the remaining near-infrared light in the solar spectrum; The transmission spectrum of the component is configured to have main transmission peaks in the blue light band (400-500 nm) and the red light band (600-700 nm) to match the photosynthetic absorption peaks of shade-loving plants.

2. The spectrally matched perovskite tandem photovoltaic module of claim 1, wherein, The top battery, middle battery, and bottom battery all adopt a reverse pin-type structure; The top cell includes a first hole transport layer, the wide-bandgap perovskite light-absorbing layer, and a first electron transport layer; The intermediate cell includes a second hole transport layer, a mid-bandgap perovskite light-absorbing layer, and a second electron transport layer. The bottom cell includes a third hole transport layer, the narrow bandgap perovskite light-absorbing layer, and a third electron transport layer.

3. The spectrally matched perovskite tandem photovoltaic module of claim 2, wherein, At least one of the first electron transport layer, the second electron transport layer, and the third electron transport layer is an Nb-doped SnO2 layer with a band gap of 3.9 eV-4.1 eV; At least one of the first hole transport layer, the second hole transport layer, and the third hole transport layer is a composite structure layer of NiOx and self-assembled molecules.

4. The spectrally matched perovskite tandem photovoltaic module of claim 1, wherein, Both the first and second intermediate interconnect layers contain discrete island-shaped gold nanoparticle layers with a thickness of 0.3 nm to 0.5 nm.

5. The spectrally matched perovskite tandem photovoltaic module of claim 1, wherein, The material of the wide-bandgap perovskite light-absorbing layer is a perovskite of the (FACs)Pb(IBr)3 type with high bromine content. The material of the mid-bandgap perovskite light-absorbing layer is α-phase FAPbI3; The narrow bandgap perovskite light-absorbing layer is made of Cs / MA co-doped FA-Sn-Pb mixed double perovskite.

6. The spectrally matched perovskite tandem photovoltaic module of claim 1, wherein, The substrate is a flexible polyimide substrate; The component also includes an encapsulation structure, which includes a double-layer geomembrane and a halide adsorption layer disposed between the double-layer geomembrane.

7. The method of producing a spectrally matched perovskite tandem photovoltaic module according to any one of claims 1 to 6, characterized in that Includes the following steps: Step 1: Deposit the first electrode on the substrate; Step 2: Fabricate a top cell on the first electrode, including sequentially depositing a first hole transport layer, a first wide bandgap perovskite light-absorbing layer with a bandgap of 1.9 eV-2.0 eV, and a first electron transport layer; Step 3: Fabricate a first intermediate interconnect layer on the top battery; Step 4: Fabricate an intermediate cell on the first intermediate interconnect layer, including sequentially depositing a second hole transport layer, a second mid-bandgap perovskite light-absorbing layer with a bandgap of 1.4 eV-1.5 eV, and a second electron transport layer. Step 5: Fabricate a second intermediate interconnect layer on the intermediate battery; Step 6: Fabricate a bottom cell on the second intermediate interconnect layer, including sequentially depositing a third hole transport layer, a third narrow bandgap perovskite light-absorbing layer with a bandgap of 1.2 eV-1.3 eV, and a third electron transport layer; Step 7: Deposit a second electrode on the bottom cell.

8. The method of claim 7, wherein the method further comprises: The methods for preparing the first and second intermediate interconnect layers in steps three and five specifically include: depositing a gold nanoparticle layer with a thickness of 0.3 nm to 0.5 nm by thermal evaporation, and forming the gold nanoparticles into a discrete island distribution by controlling the deposition rate and substrate temperature.

9. The method for preparing a spectrally matched perovskite tandem photovoltaic module according to claim 7, characterized in that, The method for preparing the wide-bandgap perovskite light-absorbing layer in step two includes: using a two-step spin-coating method or a gas-assisted solution method, spin-coating a bromine-containing perovskite precursor solution under an inert atmosphere, and then annealing it at 100-150°C.

10. The spectrally matched perovskite tandem photovoltaic module and its preparation method according to claim 7, characterized in that, The method for preparing the narrow bandgap perovskite light-absorbing layer in step six includes: under the protection of an inert atmosphere, mixing Sn-containing materials... 2+ and Pb 2+ The mixed precursor solution was spin-coated and then subjected to stepped annealing at 70-100℃ to inhibit Sn. 2+ Oxidation.

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