A thin-film photovoltaic module with dimming function and its preparation method

Abstract

A thin-film photovoltaic module with dimming function and its preparation method, belonging to the field of photovoltaic power generation, includes transparent conductive glass, an electron transport layer, a semi-transparent perovskite light-absorbing layer, a hole transport layer, an electrode layer, a dimming film layer and a metal oxide conductive layer stacked in sequence on the transparent conductive glass; the dimming film layer adopts a liquid crystal layer and / or a tungsten trioxide layer; this solution integrates two dimming function layers, the liquid crystal layer and the tungsten trioxide layer, and can control the transparency of the two dimming layers separately or jointly by adjusting the temperature of the liquid crystal layer or applying an external electric field to it, and applying an external electric field to the tungsten trioxide layer, thereby achieving more precise light transmittance adjustment.

Description

Technical Field

[0001] The present invention belongs to the field of photovoltaic power generation, and in particular relates to a thin-film photovoltaic component combined with a dimming function and a preparation method thereof. Background Art

[0002] In recent years, with the development of building energy conservation and the new energy vehicle industry, photovoltaic modules with dimming functions have become a key demand in building-integrated photovoltaics (BIPV) and automotive photovoltaics. Although traditional photovoltaic modules have the ability to generate electricity, they cannot meet the needs of building shading and light regulation. Perovskite materials have become a research hotspot for new photovoltaic materials due to their high photoelectric conversion efficiency, adjustable band gap, and solution processing properties. However, existing perovskite photovoltaic modules still have the following technical bottlenecks:

[0003] 1. A single perovskite component cannot achieve dimming and power generation functions simultaneously;

[0004] 2. Insufficient optimization of the dimming film layer components affects the adjustability of light transmittance and photoelectric conversion efficiency;

[0005] 3. The problem of charge recombination at the interface between the dimming layer and the photovoltaic layer needs to be solved urgently.

[0006] Chinese patent publication number CN109962163A discloses a photovoltaic film and its preparation method. The photovoltaic film includes transparent conductive glass, an electron transport layer, a translucent perovskite light-absorbing layer, a hole transport layer, an electrode layer, and a dimming film layer, which are sequentially stacked on the transparent conductive glass. The dimming function is achieved through a composite film (a polymer network in which polymers and liquid crystals coexist) by adjusting its temperature or applying an external electric field to it, thereby controlling the transparency of the dimming film layer. However, this solution has the problem of insufficient balance between the film's transmittance and photoelectric efficiency. Further optimization of the components and ratio of the dimming film layer is needed to improve the film's photoelectric conversion efficiency and light transmittance.

[0007] Chinese patent publication number CN109962163A discloses a solar cell comprising a stacked first transparent electrode, a second transparent electrode, and a perovskite layer disposed between the first and second transparent electrodes. The perovskite layer comprises a perovskite material that, upon absorbing sunlight, converts sunlight energy into electrical energy for power generation. When power is applied to the solar cell, the perovskite material acts as a luminescent material, converting electrical energy into light energy for emission. However, this solution's material stability and conversion efficiency remain to be improved, requiring further optimization of the perovskite material's performance to enhance the solar cell's photoelectric conversion efficiency and stability. Summary of the Invention

[0008] In view of the above-mentioned deficiencies in the prior art, an object of the present invention is to provide a thin-film photovoltaic module combined with a dimming function.

[0009] Another object of the present invention is to provide a method for preparing a thin-film photovoltaic module combined with a dimming function.

[0010] In order to achieve the above-mentioned purpose, the present invention adopts the following technical solutions.

[0011] A thin-film photovoltaic module with dimming function includes transparent conductive glass, an electron transport layer, a semi-transparent perovskite light-absorbing layer, a hole transport layer, an electrode layer, a dimming film layer, and a metal oxide conductive layer sequentially stacked on the transparent conductive glass; the dimming film layer adopts a liquid crystal layer and / or a tungsten trioxide layer; wherein:

[0012] Liquid crystal layer: composed of nematic liquid crystal and conductive polymer, the transmittance is dynamically adjusted by electric field regulation;

[0013] Tungsten trioxide layer: prepared by sol-gel method, and realizes electrochromic dimming through lithium ion insertion / extraction;

[0014] Metal oxide conductive layer: contains metal oxide.

[0015] The electron transport layer is prepared by spin coating a 5-15 wt% tin dioxide aqueous solution on a transparent conductive glass substrate at a spin coating speed of 2000-5000 rpm for 15-60 seconds, and then annealing in an air atmosphere for 15-120 minutes at an annealing temperature of 150° C. to obtain the electron transport layer.

[0016] The semi-transparent perovskite light-absorbing layer is a lead iodide-based perovskite film in a DMF / DMSO mixed solvent system. The preparation method is as follows: using lead iodide, N,N-dimethylformamide and dimethyl sulfoxide, dissolving the lead iodide in a mixed solution of N,N-dimethylformamide and dimethyl sulfoxide, with a lead iodide concentration of 0.8 to 1.5 mol / L and a volume ratio of N,N-dimethylformamide to dimethyl sulfoxide of 4 to 19, and spin-coating the film on a transparent conductive glass with an electron transport layer grown thereon at a spin-coating speed of 1500 to 5000 rpm. The method comprises the following steps: spin coating at a speed of 1300 to 5000 rpm for 20 to 60 seconds, annealing at 70 to 150 degrees Celsius for 0 to 60 minutes after spin coating to obtain a lead iodide thin film; after the lead iodide thin film is cooled, spin coating is performed on an isopropanol solution of iodomethane with a concentration of 50 to 100 mg / ml, and adding chloromethylamine and bromomethylamine at a concentration of 0 to 15 mg / ml to the isopropanol solution of iodomethane, at a speed of 1300 to 5000 rpm for 20 to 60 seconds, and annealing at 150°C for 15 to 60 minutes after spin coating to achieve phase transition and obtain a semi-transparent perovskite light-absorbing layer.

[0017] The hole transport layer is made of 2,2',7,7'-tetrakis[N,N-di(4-methoxyphenyl)amino]-9,9'-spirobifluorene (Spiro-OMeTAD) or poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA) with a thickness of 50-300 nanometers.

[0018] The liquid crystal layer is composed of the following components: a host liquid crystal: 4-cyanobiphenyl; a chiral dopant: R5011 at a concentration of 0.5-1.5 wt% or S5011 at a concentration of 0.5-1.5 wt%; a photoinitiator: chlorothioxanthone at an addition amount of 0.1-0.3 wt%; and a polymerizable monomer that is a mixture of a liquid crystal UV polymerizable monomer and a non-liquid crystal UV polymerizable monomer, with the mixing molar ratio of liquid crystal and non-liquid crystal monomers being 3:1.

[0019] Its preparation method:

[0020] Step 1, mixing system: mixing a host liquid crystal, a chiral dopant, a photoinitiator and a polymerizable monomer to obtain a mixed system;

[0021] Step 2, solution preparation: add the mixed system into chlorobenzene and dissolve it. The concentration of the mixed system is 15wt% and the dissolution temperature is 60°C.

[0022] Step 3, spin coating process: spin coating speed 3000 rpm / 30s, spin coating time 30s, precursor film thickness 50±2nm;

[0023] Step 4, UV curing: use a light intensity of 50mW / cm 2 The film was exposed to 365 nm ultraviolet light for 30 seconds, and then thermally annealed at 80° C. for 5 minutes to obtain a liquid crystal layer.

[0024] The tungsten trioxide layer is formed by a sol-gel process:

[0025] Step 1, precursor solution: hydrolyze tungsten n-butoxide, adjust the pH to 2.5 with dilute hydrochloric acid, and hydrolyze for 4 hours to obtain a sol generated by the hydrolysis of tungsten n-butoxide;

[0026] Step 2, film forming process: adopt dip coating method, use a sizing machine to apply sol coating, pull speed is 5cm / min, immersion time is 30s;

[0027] Step 3, annealing process: heating rate of 10°C, preheating at 100°C for 1 hour, then heating rate of 10°C, main annealing at 350°C for 1 hour to obtain a tungsten trioxide layer.

[0028] The preparation method of the metal oxide conductive layer is as follows:

[0029] Step 1: Laying silver nanowires on a substrate:

[0030] A 20mg / mL silver nanowire solution was passed through a funnel covered with filter paper to remove the alcohol and evenly disperse the silver nanowires on the filter paper surface. A substrate was placed on the funnel and vacuum was initiated. The negative pressure within the funnel pressed the silver nanowires against the substrate. The funnel and filter paper were then removed, leaving the silver nanowires on the substrate, completing the silver nanowire grid layout.

[0031] Step 2: Using an atmospheric pressure plasma jet system, plasma and thin film deposition is performed on the surface of the silver nanowires:

[0032] The atmospheric pressure plasma jet system includes: a gas supply module consisting of a main gas, a carrier gas and a precursor solution, a plasma excitation module consisting of a DC pulse power supply and a nozzle, an ultrasonic generator, and a deposition module consisting of a substrate and an XY moving stage;

[0033] Step 201: Using nitrogen as the main gas, a high-voltage pulse current is passed through the nozzle to decompose the main gas and generate plasma;

[0034] In step 202, a mixture of argon and hydrogen is used as a carrier gas, with the volume ratio of argon to hydrogen being 93:7. An ultrasonic generator is used to atomize the precursor solution into micron-sized droplets to form an atomized precursor.

[0035] In step 203, when the atomized precursor enters the nozzle along with the carrier gas, the high-energy ion particles evaporate the outer layer of water, forming dry solid / gaseous reactant particles. The high-energy ion particles continuously bombard the reactant particles, causing them to decompose and react with oxygen in the atmosphere to generate oxidized particles, which are then deposited on the substrate heated to 180°C to form a thin film.

[0036] The precursor solution was prepared by dissolving zinc nitrate hexahydrate and gallium nitrate in deionized water. At this time, the zinc nitrate hexahydrate was 164.3g / L and the gallium nitrate was 20g / L. The pulse duty cycle of the plasma excitation module was set to 22.2%, the total cycle length was 36μs, the on and off time ratio was 8:28, and the pulse frequency was 27.78kHz. The raster scanning speed was 6mm / s.

[0037] A method for preparing a thin-film photovoltaic module with a dimming function comprises the following steps:

[0038] Step S1, sequentially preparing an electron transport layer, a semi-transparent perovskite light absorbing layer, a hole transport layer and an electrode layer on a transparent conductive glass to obtain a perovskite solar device;

[0039] Step S2, preparing a dimming film layer of a liquid crystal layer and / or a tungsten trioxide layer, and attaching it to the perovskite solar device;

[0040] Step S3: preparing a metal oxide conductive layer and attaching it to the dimming film layer to obtain the thin film photovoltaic module of the present invention.

[0041] Compared with the prior art, the present invention has the following beneficial effects:

[0042] 1. Innovation in functional layer structure: A liquid crystal layer and / or a tungsten trioxide layer and a metal oxide conductive layer are sequentially arranged above the perovskite cell electrode layer to achieve the integration of dimming and power generation functions; this meets the needs of buildings and vehicles for sunshade, dimming and other functions, overcoming the shortcomings of existing perovskite photovoltaic modules that cannot achieve dimming and power generation simultaneously; and, the components and ratio of the dimming film layer are optimized to improve light transmittance.

[0043] 2. Material system optimization: Use a specific ratio of perovskite light-absorbing layer materials (lead iodide / DMF / DMSO mixed solution) and carrier transport layers (SnO2 electron transport layer, Spiro-OMeTAD hole transport layer) to improve photoelectric performance.

[0044] 3. Interface regulation technology: The metal oxide conductive layer is used to reduce the interface charge recombination between the dimming film layer and the photovoltaic layer, thereby improving the photoelectric conversion efficiency of the device.

[0045] 4. This technical solution is simple to operate and low-cost, providing a new type of composite photovoltaic module solution for the BIPV and automotive photovoltaic fields. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 It is a schematic diagram of the structure of the atmospheric pressure plasma jet system;

[0047] Figure 2 It is a schematic diagram of the raster scanning of the nozzle;

[0048] Figure 3 The top views of the metal oxide conductive layer at different scanning speeds under low magnification SEM, where Figure a represents fast scanning, Figure b represents standard scanning, and Figure c represents slow scanning;

[0049] Figure 4 is an SEM image of the metal oxide conductive layer; among them, Figure a is an untreated nanosilver wire, Figure b is a nanosilver wire treated with pure plasma, and Figure c is a nanosilver wire treated with plasma and thin film deposition. DETAILED DESCRIPTION

[0050] The present invention will be described in further detail below with reference to the accompanying drawings.

[0051] A thin-film photovoltaic module with dimming function includes transparent conductive glass, an electron transport layer (thickness 30-50nm), a semi-transparent perovskite light absorption layer (thickness 300-500nm), a hole transport layer (thickness 50-300nm), an electrode layer (thickness 70-90nm), a dimming film layer (thickness 1-5μm) and a metal oxide conductive layer (thickness 260-410nm) stacked in sequence on the transparent conductive glass.

[0052] Transparent conductive glass: FTO or ITO conductive glass is used.

[0053] Electron transport layer: A 5-15 wt% tin dioxide aqueous solution is spin-coated on a transparent conductive glass substrate at a speed of 2000-5000 rpm for 15-60 seconds, followed by annealing in air at 150°C for 15-120 minutes to obtain an electron transport layer.

[0054] Semi-transparent perovskite light-absorbing layer: It is a lead iodide-based perovskite film in a DMF / DMSO mixed solvent system. It captures and absorbs the photons of light irradiating the film to generate electron-hole pairs. The electrons and holes are respectively transferred to the two electrodes through the electron transport layer and the hole transport layer to output electrical energy and complete the photoelectric conversion. Its preparation method is as follows: using lead iodide, N,N-dimethylformamide (DMF) and dimethyl sulfoxide (DMSO), dissolving lead iodide in a mixed solution of N,N-dimethylformamide and dimethyl sulfoxide, with a lead iodide concentration of 0.8-1.5 mol / L and a volume ratio of N,N-dimethylformamide to dimethyl sulfoxide of 4-19, and spin coating on the transparent conductive glass with the electron transport layer grown on it, with a spin coating speed of 1500-5000 rpm and a time of 20- The method comprises the following steps: spin coating the lead iodide film and annealing the film at 70 to 150 degrees Celsius for 0 to 60 minutes after spin coating to obtain a lead iodide film; after the lead iodide film is cooled, spin coating an isopropanol solution of iodomethane with a concentration of 50 to 100 mg / ml, and adding chloromethylamine and bromomethylamine with a concentration of 0 to 15 mg / ml to the isopropanol solution of iodomethane, with a spin coating speed of 1300 to 5000 rpm for 20 to 60 seconds, and annealing the film at 150°C for 15 to 60 minutes to achieve phase transition.

[0055] Hole transport layer: 2,2',7,7'-tetrakis[N,N-di(4-methoxyphenyl)amino]-9,9'-spirobifluorene (Spiro-OMeTAD) or poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA), with a thickness of 50~300nm.

[0056] Electrode layer: Made of Au or Ag. Preferably, made of gold with a thickness of 70-90 nm.

[0057] The dimming film layer utilizes a liquid crystal layer (SmA-N* nematic liquid crystal) and / or a tungsten trioxide layer (prepared by the sol-gel method). The transparency of this layer can be controlled by adjusting its temperature or applying an external electric field, thereby adjusting light transmittance. The liquid crystal layer utilizes a SmA-N* nematic liquid crystal material doped with the chiral compound R5011 or S5011. The photoinitiator is chlorothioxanthone. The liquid crystal material is nematic liquid crystal 4-cyanobiphenyl. The polymerizable monomer is a mixture of a liquid crystal UV-polymerizable monomer (e.g., C6M, 6-cyano-1-(4-methoxyphenyl)hexane) and a non-liquid crystal UV-polymerizable monomer (e.g., CB15, 4-methoxybiphenylcarboxylic acid).

[0058] Liquid crystal layer: Based on a liquid crystal material system of nematic liquid crystal (SmA-N* phase transition, phase transition temperature T = 85~95°C), the liquid crystal molecular orientation is regulated by a temperature gradient ΔT = 5~10°C or an external electric field of V = 0~15V and f = 1~kHz to achieve dynamic adjustment of light transmittance.

[0059] The liquid crystal layer is composed of the following components: a host liquid crystal: 4-cyanobiphenyl (5CB); a chiral dopant: R5011 (S-5-cyano-2,3,5,6-tetrafluorobiphenyl, concentration 0.5-1.5 wt%) or S5011 (R-configuration homologue, concentration 0.5-1.5 wt%); a photoinitiator: chlorothioxanthone (addition amount 0.1-0.3 wt%); and a polymerizable monomer: a mixture of a liquid crystalline UV-polymerizable monomer (e.g., C6M, 6-cyano-1-(4-methoxyphenyl)hexane) and a non-liquid crystalline UV-polymerizable monomer (e.g., CB15, 4-methoxybibenzoic acid), with the molar ratio of liquid crystalline to non-liquid crystalline monomers being 3:1.

[0060] Liquid crystal layer, preparation method:

[0061] Step 1, mixing system: mixing a host liquid crystal, a chiral dopant, a photoinitiator and a polymerizable monomer to obtain a mixed system;

[0062] Step 2, solution preparation: add the mixed system into chlorobenzene and dissolve it. The concentration of the mixed system is 15wt% and the dissolution temperature is 60°C.

[0063] Step 3, spin coating process: spin coating speed 3000 rpm / 30s, spin coating time 30s, precursor film thickness 50±2nm;

[0064] Step 4, UV curing: use a light intensity of 50mW / cm 2 The film was exposed to 365 nm ultraviolet light for 30 seconds and then cured by thermal annealing at 80°C for 5 minutes to obtain a liquid crystal layer.

[0065] Tungsten trioxide layer, using sol-gel process:

[0066] Step 1, precursor solution: hydrolyze tungsten n-butoxide, adjust the pH to 2.5 with dilute hydrochloric acid, and hydrolyze for 4 hours to obtain a sol generated by the hydrolysis of tungsten n-butoxide;

[0067] Step 2, film forming process: adopt dip coating method, use a sizing machine to apply sol coating, pull speed is 5cm / min, immersion time is 30s;

[0068] Step 3, annealing process: heating rate of 10°C, preheating at 100°C for 1 hour, then heating rate of 10°C, main annealing at 350°C for 1 hour to obtain a tungsten trioxide layer.

[0069] Metal oxide conductive layer: used to reduce the interfacial charge recombination between the dimming layer and the photovoltaic layer and improve the photoelectric conversion efficiency of the device.

[0070] The metal oxide conductive layer, as a transparent conductive film for the front electrode, requires not only high conductivity and high light transmittance, but also a high haze, which helps to increase the optical path length and the probability of light sealing when light passes through the semi-transparent perovskite light-absorbing layer.

[0071] In silicon-based solar cells, increasing the haze of the metal oxide conductive layer is beneficial to improving the photoelectric conversion efficiency. However, in perovskite photovoltaic modules, increasing the haze of the metal oxide conductive layer can lead to poor photoelectric conversion efficiency.

[0072] Therefore, this solution requires reducing the haze of the metal oxide conductive layer in the perovskite photovoltaic module.

[0073] The preparation method of the metal oxide conductive layer is as follows:

[0074] Step 1: Lay silver nanowires on a substrate.

[0075] Silver nanowires are commercially available with the following specifications: diameter: 90±10 nm; average length: 20 μm.

[0076] The silver nanowires were evenly dispersed in 95% alcohol to obtain a 20 mg / mL (w / v) silver nanowire solution. The silver nanowire solution was then filtered through a funnel with filter paper to remove the alcohol and evenly disperse the silver nanowires on the surface of the filter paper. The substrate was attached to the funnel and vacuuming began. The negative pressure in the funnel pressed the silver nanowires against the substrate. After one hour, the funnel and filter paper were removed, leaving the silver nanowires on the substrate, completing the grid laying of the silver nanowires.

[0077] Step 2: Using an atmospheric pressure plasma jet system, plasma and thin film deposition is performed on the surface of the nano silver wire.

[0078] Atmospheric pressure plasma jet system, such as Figure 1 As shown, the system comprises a gas supply module consisting of a primary gas, carrier gas, and precursor solution; a plasma excitation module consisting of a DC pulse power supply and nozzle; an ultrasonic generator; and a deposition module consisting of a substrate and an XY motion stage. These components work together to achieve the complete process of "plasma generation → precursor activation → thin film deposition."

[0079] In step 201, nitrogen is used as the main gas, and a high-voltage pulse current is passed through the main gas to decompose the main gas and generate plasma in the nozzle. The plasma forms a directional jet at the nozzle, providing energy carriers for subsequent reactions.

[0080] In step 202, a mixture of argon and hydrogen is used as a carrier gas, with a volume ratio of 93:7. An ultrasonic generator is used to atomize the precursor solution into micron-sized droplets, forming an atomized precursor. The carrier gas stabilizes the flow field and protects the precursor from oxidation.

[0081] The precursor solution is prepared by dissolving zinc nitrate hexahydrate (Zinc Nitrate, 6-Hydrate Crystal) and gallium (III) nitrate hydrate) in deionized water. At this time, the zinc nitrate hexahydrate is 164.3g / L and the gallium nitrate is 20g / L (calculated as anhydrous Ga(NO3)3). The pulse duty cycle of the plasma excitation module is set to 22.2%, the total cycle length is 36μs, the on-off time ratio is 8:28, and the pulse frequency is 27.78kHz.

[0082] In step 203, when the atomized precursor enters the nozzle along with the carrier gas, high-energy ion particles evaporate the outer layer of water, forming dry solid / gaseous reactant particles. In addition, high-energy ion particles (such as high-speed electrons and ions) continuously bombard the reactant particles, causing them to decompose and react with oxygen in the atmosphere to generate oxidized particles, which are deposited on the substrate heated to 180°C to form a thin film.

[0083] The substrate is pre-coated with silver nanowires and heated to 180°C to increase the migration rate of the reactant particles and promote their uniform adsorption on the substrate surface. During the deposition process, the reactive oxide species diffuse and collide on the substrate surface, forming a solid film through chemical bond recombination.

[0084] The XY moving stage controls the position of the substrate to ensure uniform coverage of the deposition area. In order to achieve uniform film deposition, the XY moving stage is used to move the substrate so that the nozzle is within a range of 5×5 cm. 2The nozzle is then raster-scanned on the substrate, with the distance between the nozzle and the substrate fixed at 2 mm. The raster scanning interval is 2 mm, and the film thickness is kept consistent from side to side. The raster scanning is used to evenly sweep the nozzle across the substrate with the silver nanowires, achieving the goal of simultaneously coating the film and soldering the silver wires. Figure 2 is a schematic diagram of the raster scanning of the nozzle; Figure 2 shown.

[0085] Set the raster scanning speed to:

[0086] Fast scan (14 mm / s): Film thickness 299 nm, haze 2.77%, sheet resistance 19.04 Ω / sq (surface roughness increased). The film surface is rough and has high haze.

[0087] Standard scan (10 mm / s): film thickness 300 nm, haze 2.56%, sheet resistance 18.67 Ω / sq.

[0088] Slow scan (6 mm / s): Film thickness 305 nm, haze 1.87%, sheet resistance 18.13 Ω / sq (smoother surface). The film surface is smoother and has lower haze.

[0089] Figure 3 This is a top view of the metal oxide conductive layer at different scanning speeds under low magnification SEM; Figure 3 In the figure, Figure a represents a fast scan, Figure b represents a standard scan, and Figure c represents a slow scan. It can be seen that the protrusions on the film surface at high scan speeds are indeed more densely distributed.

[0090] Figure 4 It is an SEM image of the metal oxide conductive layer; among them, Figure a is an untreated silver nanowire. It can be seen that the silver nanowires transferred to the substrate using the vacuum pumping method are simply placed on the upper substrate and only overlap with each other; Figure b is a pure plasma-treated silver nanowire. It can be seen that the silver nanowires are melted on the substrate and are obviously welded together; Figure c is a silver nanowire after plasma and thin film deposition treatment. It can be seen that when the precursor liquid inlet switch is turned on, the welding work can still be completed when the film is simultaneously coated in the plasma, and an additional layer of thin film is plated on the surface of the silver nanowire.

[0091] The metal oxide conductive layer of this solution adjusts the scanning speed during coating and reduces flow field changes, making the grain growth stage of the film surface smoother, thereby reducing the uneven parts of the film surface and improving the performance of photoelectric conversion efficiency.

[0092] The metal oxide conductive layer of this solution simultaneously completes the surface pretreatment of the nano silver wires and the film laying to produce the composite material during the coating process, significantly reducing the cost and energy consumption required for the multi-step process.

[0093] The metal oxide conductive layer in this solution is produced using an atmospheric pressure plasma jet system, which improves the metal oxide conductive layer's penetration and reduces its roughness. To mitigate the reduced conductivity caused by the atmospheric pressure plasma jet system, a composite material with nanosilver wires is used.

[0094] The metal oxide conductive layer of this solution has a controllable surface roughness, which is beneficial to reducing the interface charge recombination between the dimming thin film layer and the photovoltaic layer, and improving the photoelectric conversion efficiency of the device.

[0095] A method for preparing a thin-film photovoltaic module with a dimming function comprises the following steps:

[0096] Step S1, sequentially preparing an electron transport layer, a semi-transparent perovskite light-absorbing layer, a hole transport layer and an electrode layer on a transparent conductive glass to obtain a perovskite solar device.

[0097] Step S2: preparing a dimming film layer of a liquid crystal layer and / or a tungsten trioxide layer, and attaching it to the perovskite solar device.

[0098] Step S3: preparing a metal oxide conductive layer and attaching it to the dimming film layer to obtain the thin film photovoltaic module of the present invention.

[0099] A thin-film photovoltaic module with dimming function, the working principle is as follows:

[0100] The semi-transparent perovskite light-absorbing layer captures photons and generates electron-hole pairs. The electrons and holes are transferred to the electrodes through the electron transport layer and the hole transport layer respectively, completing the photoelectric conversion.

[0101] The liquid crystal layer of the dimming film layer is a polymer network in which polymers and liquid crystals coexist. By adjusting the temperature or applying an external electric field, the transparency of the liquid crystal layer is controlled to achieve light transmittance adjustment.

[0102] The metal oxide conductive layer reduces the interface charge recombination between the dimming film layer and the photovoltaic layer, thereby improving the photoelectric conversion efficiency.

[0103] Example 1 (liquid crystal dimming type).

[0104] A thin-film photovoltaic module with dimming function includes transparent conductive glass, an electron transport layer, a semi-transparent perovskite light-absorbing layer, a hole transport layer, an electrode layer, a dimming film layer and a metal oxide conductive layer sequentially stacked on the transparent conductive glass.

[0105] The dimming film layer is a liquid crystal layer.

[0106] A method for preparing a thin-film photovoltaic module with a dimming function comprises the following steps:

[0107] Step S1, sequentially preparing an electron transport layer, a semi-transparent perovskite light-absorbing layer, a hole transport layer and an electrode layer on a transparent conductive glass to obtain a perovskite solar device.

[0108] Step S2: preparing a dimming film layer of the liquid crystal layer and attaching it to the perovskite solar device.

[0109] Step S3: preparing a metal oxide conductive layer and attaching it to the dimming film layer to obtain the thin film photovoltaic module of the present invention.

[0110] Dimming mechanism: By changing the liquid crystal arrangement state through temperature control (20-80℃) or applying voltage (0-10V), the transmittance can be continuously adjusted from 50% to 90%.

[0111] Example 2 (electrochromic type).

[0112] A thin-film photovoltaic module with dimming function includes transparent conductive glass, an electron transport layer, a semi-transparent perovskite light-absorbing layer, a hole transport layer, an electrode layer, a dimming film layer and a metal oxide conductive layer sequentially stacked on the transparent conductive glass.

[0113] The dimming film layer is a tungsten trioxide layer.

[0114] A method for preparing a thin-film photovoltaic module with a dimming function comprises the following steps:

[0115] Step S1, sequentially preparing an electron transport layer, a semi-transparent perovskite light-absorbing layer, a hole transport layer and an electrode layer on a transparent conductive glass to obtain a perovskite solar device.

[0116] Step S2: preparing a dimming film layer of tungsten trioxide layer and attaching it on the perovskite solar device.

[0117] Step S3: preparing a metal oxide conductive layer and attaching it to the dimming film layer to obtain the thin film photovoltaic module of the present invention.

[0118] Dimming mechanism: Under an external electric field, WO3 generates lithium ions (Li + ) embedding / de-embedding, triggering valence changes, resulting in color changes and adjusting the intensity of transmitted light. Performance characteristics: response time <1s, visible light transmittance adjustment range of 40%-80%.

[0119] Example 3 (composite dimming type).

[0120] A thin-film photovoltaic module with dimming function includes transparent conductive glass, an electron transport layer, a semi-transparent perovskite light-absorbing layer, a hole transport layer, an electrode layer, a dimming film layer and a metal oxide conductive layer sequentially stacked on the transparent conductive glass.

[0121] The dimming film layer is a liquid crystal layer and a tungsten trioxide layer.

[0122] The liquid crystal layer is formed by spin coating on the tungsten trioxide layer. + Insertion / ejection enables color depth adjustment; the liquid crystal layer achieves rapid transmittance changes through polarization control. Synergistic Working Mechanism: In low-voltage mode (0-3V), only the liquid crystal layer is activated, achieving a transmittance of 40-60% through polarization adjustment, with a response time of <100ms (the liquid crystal layer dominates). In high-voltage mode (3-5V), both the electrochromic layer and the liquid crystal layer are activated simultaneously, extending the transmittance adjustment range to 40-80%, with a response time of <500ms (the tungsten trioxide layer dominates).

[0123] The superimposed structure of the liquid crystal layer and the tungsten trioxide layer takes into account the transmittance adjustment range and response time through the coordinated regulation of temperature control and electric field.

[0124] A method for preparing a thin-film photovoltaic module with a dimming function comprises the following steps:

[0125] Step S1, sequentially preparing an electron transport layer, a semi-transparent perovskite light-absorbing layer, a hole transport layer and an electrode layer on a transparent conductive glass to obtain a perovskite solar device.

[0126] Step S2: preparing a dimming thin film layer and attaching it to the perovskite solar device.

[0127] Step S3: preparing a metal oxide conductive layer and attaching it to the dimming film layer to obtain the thin film photovoltaic module of the present invention.

[0128] This solution integrates two dimming functional layers: a liquid crystal layer and a tungsten trioxide layer. The transparency of the two dimming layers can be controlled separately or jointly by adjusting the temperature of the liquid crystal layer or applying an external electric field to it, and applying an external electric field to the tungsten trioxide layer, thereby achieving more precise transmittance adjustment.

[0129] The metal oxide conductive layer is arranged on the dimming film layer to reduce the interface charge recombination between the dimming film layer and the photovoltaic layer and improve the photoelectric conversion efficiency of the device.

[0130] It is understandable that those skilled in the art can make equivalent substitutions or changes based on the technical solution and inventive concept of the present invention, and all these changes or substitutions should fall within the scope of protection of the claims attached to the present invention.

Claims

1. A thin-film photovoltaic module with a dimming function, characterized in that: The device comprises a transparent conductive glass, an electron transport layer, a semi-transparent perovskite light-absorbing layer, a hole transport layer, an electrode layer, a dimming film layer and a metal oxide conductive layer stacked sequentially on the transparent conductive glass; the dimming film layer adopts a liquid crystal layer and / or a tungsten trioxide layer; wherein: Liquid crystal layer: composed of nematic liquid crystal and conductive polymer, the transmittance is dynamically adjusted by electric field regulation; Tungsten trioxide layer: prepared by sol-gel method, and realizes electrochromic dimming by lithium ion insertion or extraction; The metal oxide conductive layer is a composite material prepared by plasma and thin film deposition on the surface of the nano silver wire using an atmospheric pressure plasma jet system.

2. The thin-film photovoltaic module with dimming function according to claim 1, characterized in that: The electron transport layer is prepared by spin coating a 5-15 wt% tin dioxide aqueous solution on a transparent conductive glass substrate at a spin coating speed of 2000-5000 rpm for 15-60 seconds, and then annealing in an air atmosphere for 15-120 minutes at an annealing temperature of 150° C. to obtain the electron transport layer.

3. The thin-film photovoltaic module with dimming function according to claim 1, characterized in that: The semi-transparent perovskite light-absorbing layer is a lead iodide-based perovskite film in a mixed solvent system of DMF and DMSO. The preparation method is as follows: using lead iodide, N,N-dimethylformamide and dimethyl sulfoxide, dissolving the lead iodide in a mixed solution of N,N-dimethylformamide and dimethyl sulfoxide, with a lead iodide concentration of 0.8 to 1.5 mol / L and a volume ratio of N,N-dimethylformamide to dimethyl sulfoxide of 4 to 19, and spin-coating the film on a transparent conductive glass with an electron transport layer grown thereon at a spin-coating speed of 1500 to 5000 rpm. The method comprises the following steps: spin coating at a speed of 1300 to 5000 rpm for 20 to 60 seconds, annealing at 70 to 150 degrees Celsius for 0 to 60 minutes after spin coating to obtain a lead iodide thin film; after the lead iodide thin film is cooled, spin coating is performed on an isopropanol solution of iodomethane with a concentration of 50 to 100 mg / ml, and adding chloromethylamine and bromomethylamine at a concentration of 0 to 15 mg / ml to the isopropanol solution of iodomethane, at a speed of 1300 to 5000 rpm for 20 to 60 seconds, and annealing at 150°C for 15 to 60 minutes after spin coating to achieve phase transition and obtain a semi-transparent perovskite light-absorbing layer.

4. The thin-film photovoltaic module with dimming function according to claim 1, characterized in that: The hole transport layer is made of 2,2',7,7'-tetrakis[N,N-di(4-methoxyphenyl)amino]-9,9'-spirobifluorene or poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine], and has a thickness of 50-300 nm.

5. The thin-film photovoltaic module with dimming function according to claim 1, characterized in that: The liquid crystal layer is composed of the following components: a main liquid crystal of 4-cyanobiphenyl; a chiral dopant of 0.5-1.5 wt% R5011 or 0.5-1.5 wt% S5011; a photoinitiator of 0.1-0.3 wt% chlorothioxanthone; and a polymerizable monomer of a mixture of a liquid crystal ultraviolet polymerizable monomer and a non-liquid crystal ultraviolet polymerizable monomer, wherein the molar ratio of the liquid crystal and non-liquid crystal monomers is 3:

1. The preparation method of the liquid crystal layer is as follows: Step 1, mixing system: mixing a host liquid crystal, a chiral dopant, a photoinitiator and a polymerizable monomer to obtain a mixed system; Step 2, solution preparation: add the mixed system into chlorobenzene and dissolve it. The concentration of the mixed system is 15wt% and the dissolution temperature is 60°C. Step 3, spin coating process: spin coating speed 3000 rpm / 30s, spin coating time 30s, precursor film thickness 50±2nm; Step 4, UV curing: use a light intensity of 50mW / cm 2 The film was exposed to 365 nm ultraviolet light for 30 seconds, and then thermally annealed at 80° C. for 5 minutes to obtain a liquid crystal layer.

6. A thin-film photovoltaic module with dimming function according to claim 1 or 5, characterized in that: The tungsten trioxide layer is formed by a sol-gel process: Step 1, precursor solution: hydrolyze tungsten n-butoxide, adjust the pH to 2.5 with dilute hydrochloric acid, and hydrolyze for 4 hours to obtain a sol generated by the hydrolysis of tungsten n-butoxide; Step 2, film forming process: adopt dip coating method, use a sizing machine to apply sol coating, pull speed is 5cm / min, immersion time is 30s; Step 3, annealing process: heating rate of 10°C, preheating at 100°C for 1 hour, then heating rate of 10°C, main annealing at 350°C for 1 hour to obtain a tungsten trioxide layer.

7. The thin-film photovoltaic module with dimming function according to claim 6, characterized in that: The preparation method of the metal oxide conductive layer is as follows: Step 1: Laying silver nanowires on a substrate: A 20mg / mL silver nanowire solution was passed through a funnel covered with filter paper to remove the alcohol and evenly disperse the silver nanowires on the filter paper surface. A substrate was placed on the funnel and vacuum was initiated. The negative pressure within the funnel pressed the silver nanowires against the substrate. The funnel and filter paper were then removed, leaving the silver nanowires on the substrate, completing the silver nanowire grid layout. Step 2: Using an atmospheric pressure plasma jet system, plasma and thin film deposition is performed on the surface of the silver nanowires: The atmospheric pressure plasma jet system includes: a gas supply module consisting of a main gas, a carrier gas and a precursor solution, a plasma excitation module consisting of a DC pulse power supply and a nozzle, an ultrasonic generator, and a deposition module consisting of a substrate and an XY moving stage; Step 201: Using nitrogen as the main gas, a high-voltage pulse current is passed through the nozzle to decompose the main gas and generate plasma; In step 202, a mixture of argon and hydrogen is used as a carrier gas, with the volume ratio of argon to hydrogen being 93:

7. An ultrasonic generator is used to atomize the precursor solution into micron-sized droplets to form an atomized precursor. In step 203, when the atomized precursor enters the nozzle along with the carrier gas, the high-energy ion particles evaporate the outer layer of the precursor to form dry reactant particles. The high-energy ion particles continuously bombard the reactant particles, causing them to decompose and react with oxygen in the atmosphere to generate oxidized particles that are deposited on the substrate heated to 180°C to form a thin film.

8. The thin-film photovoltaic module combined with dimming function according to claim 7, characterized in that: The precursor solution was prepared by dissolving zinc nitrate hexahydrate and gallium nitrate in deionized water. At this time, the zinc nitrate hexahydrate was 164.3g / L and the gallium nitrate was 20g / L. The pulse duty cycle of the plasma excitation module was set to 22.2%, the total cycle length was 36μs, the on and off time ratio was 8:28, and the pulse frequency was 27.78kHz. The raster scanning speed was 6mm / s.

9. A method for preparing a thin-film photovoltaic module with dimming function according to any one of claims 1 to 8, characterized in that: The following steps are involved: Step S1, sequentially preparing an electron transport layer, a semi-transparent perovskite light absorbing layer, a hole transport layer and an electrode layer on a transparent conductive glass to obtain a perovskite solar device; Step S2, preparing a dimming film layer of a liquid crystal layer and / or a tungsten trioxide layer, and attaching it to the perovskite solar device; Step S3: preparing a metal oxide conductive layer and attaching it to the dimming film layer to obtain the thin film photovoltaic module of the present invention.

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