Perovskite battery and preparation method thereof, photovoltaic module

Abstract

The application provides a perovskite cell and a preparation method and a photovoltaic module thereof. The perovskite cell comprises a substrate, a transparent conductive layer, a hole transport layer, a perovskite light absorption layer and an electron transport layer which are stacked on the substrate, wherein the hole transport layer comprises a self-assembled monolayer and nano-sized Lewis acid-base catalytic particles dispersed in the self-assembled monolayer. The perovskite cell of the application realizes highly uniform coverage of the self-assembled monolayer material on the transparent conductive layer by arranging the nano-sized Lewis acid-base catalytic particles in the hole transport layer, thereby improving the overall performance of the perovskite solar cell and the stability of the device.

Description

Technical Field

[0001] This application relates to the field of perovskite battery technology, and in particular to a perovskite battery and its preparation method, as well as a photovoltaic module. Background Technology

[0002] Perovskite solar cells, as a representative of third-generation photovoltaic technology, possess advantages such as high conversion efficiency, low-light power generation capability, and relatively low manufacturing cost. The basic structure of a typical perovskite solar cell includes an electron transport layer, a perovskite light-absorbing layer, a hole transport layer, and a metal electrode. A transparent conductive layer (TCO layer) is disposed on the side of the hole transport layer (HTL layer) facing away from the perovskite light-absorbing layer. The placement of the hole transport layer over the transparent conductive layer facilitates efficient hole extraction, contributing to improved cell efficiency.

[0003] Self-assembled monomolecule materials are a commonly used hole transport layer material. They are generally composed of anchoring groups, alkyl bridges, and terminal groups. The anchoring groups are used to firmly bind the transparent conductive layer, while the terminal groups regulate the interface energy level and wettability to achieve efficient carrier transport, passivate interface defects, and improve the efficiency and stability of perovskite solar cells. The alkyl bridges are the "skeleton" connecting the anchoring groups and the terminal groups, and are usually composed of saturated carbon chains.

[0004] The terminal groups of self-assembled monomolecules exist in the form of conjugated structures such as carbazole groups, dibenzocarbazole groups, acridine groups, phenothiazine groups, or phenyl groups. In the process of preparing self-assembled monolayers as hole transport layers using self-assembled monomolecules as raw materials through wet coating processes, due to the π-π stacking effect, van der Waals forces, and hydrophobic alkyl chain interactions between molecules, the molecules of self-assembled monomolecules tend to adsorb and aggregate together rather than preferentially bind to the transparent conductive layer. This results in some areas of the transparent conductive layer surface being exposed due to gaps in the hole transport layer coverage, leading to pinholes in the hole transport layer. This reduces the photoelectric conversion efficiency of perovskite solar cells. Summary of the Invention

[0005] This application provides a perovskite solar cell and its preparation method, as well as a photovoltaic module. By introducing nano-sized Lewis acid-base catalytic particles at the interface between the hole transport layer and the transparent conductive layer, the self-assembled monomolecular material used to form the hole transport layer can be more uniformly and firmly filmed on the surface of the transparent conductive layer, thereby improving the photoelectric performance and device stability of the perovskite solar cell.

[0006] The first aspect of this application provides a perovskite solar cell, including a substrate and a transparent conductive layer, a hole transport layer, a perovskite light-absorbing layer and an electron transport layer stacked on the substrate, wherein the hole transport layer includes a self-assembled monolayer and nano-sized Lewis acid-base catalytic particles dispersed in the self-assembled monolayer.

[0007] In some optional embodiments of the first aspect of this application, the particle size of the Lewis acid-base catalytic particles is 5 nm to 20 nm.

[0008] In some optional embodiments of the first aspect of this application, the Lewis acid-base catalytic particles include at least one of alumina, aluminum chloride, silicon oxide, aluminum sulfate, ferric chloride, magnesium oxide, and calcium oxide.

[0009] In some optional embodiments of the first aspect of this application, the mass ratio of the self-assembled monolayer to the Lewis acid-base catalytic particles is 1:(0.005~0.01).

[0010] In some optional embodiments of the first aspect of this application, the materials for self-assembled monolayers include [2-(9H-carbazole-9-yl)ethyl]phosphonic acid (2PACz, CAS No. 20999-38-6), [2-(3,6-dimethyl-9H-carbazole-9-yl)ethyl]phosphonic acid (Me-2PACz, CAS No. 2996161-30-7), (2-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl)phosphonic acid (MeO-2PACz, CAS No. 2377770-18-6), [2-(3,6-diphenyl-9H-carbazole-9-yl)ethyl]phosphonic acid (Ph-2PACz, CAS No. 3085827-62-6), [2-(3,6-dimethyl-9H-carbazole-9-yl)ethyl]phosphonic acid (Ph-2PACz, CAS No. 3085827-62-6), [2-(3,6-dimethyl-9H-carbazole-9-yl)ethyl]phosphonic acid (MeO ...20999-38-6), [2-(3,6-dimethyl-9H-carbazole-9-yl)ethyl]phosphonic acid (MeO-2PACz, CAS No. 20999-38-6), [2-(3,6-dimethyl-9H-carbazole-9-yl)ethyl]phosphonic acid (MeO-2PACz, CAS No. 20999-38-6), [2-(3,6-dimethyl- Iodo-9H-carbazole-9-yl)ethyl]phosphonic acid (I-2PACz, CAS No. 3026275-69-1), 2-(3,6-dibromo-9H-carbazole-9-yl)ethyl]phosphonic acid (Br-2PACz, CAS No. 2762888-11-7), 2-(3,6-dichloro-9H-carbazole-9-yl)ethyl]phosphonic acid (Cl-2PACz, CAS No. 3036926-72-1), 2-(3,6-difluoro-9H-carbazole-9-yl)ethyl]phosphonic acid (F-2PACz, CAS No. 3036926-69-6), [2-(7H-dibenzocarbazole-7-yl)ethyl]phosphonic acid (2PADCB, CAS No. 2882156-61-6) [4-(9H-carbazole-9-yl)ethyl]phosphoric acid (4PACz, CAS No. 20999-36-4), [4-(3,6-dimethyl-9H-carbazole-9-yl)butyl]phosphonic acid (Me-4PACz, CAS No. 2747959-96-0), [4-(3,6-dimethoxy-9H-carbazole-9-yl)butyl]phosphonic acid (MeO-4PACz, CAS No. 2377770-18-6), [4-(3,6-diphenyl-9H-carbazole-9-yl)butyl]phosphoric acid (Ph-4PACz, CAS No. 2814500-04-2), [4-(3,6-diiodo-9H-carbazole-9-yl)butyl]phosphonic acid (Br-4PACz, CAS No. 20999-36-4 ...O-4PACz, CAS No. 20999-36-4), [4-(3,6-diiodo-9H-carbazole-9-yl)butyl]phosphonic acid (BrO-4PACz (CAS No. 3026275-67-9), [4-(3,6-dibromo-9H-carbazole-9-yl)butyl]phosphonic acid (Br-4PACz, CAS No. 2996161-28-3), (4-(3,6-dichloro-9H-carbazole-9-yl)butyl)phosphonic acid (Cl-4PACz, CAS No. 3026275-66-8), (4-(3,6-difluoro-9H-carbazole-9-yl)butyl)phosphonic acid (F-4PACz, CAS No. 3026275-65-7), [4-[3-bromo-6-(4-methoxyphenyl)-9H-carbazole-9-yl]butyl]phosphonic acid (BrMeOPh-4PACz, CAS No. 3053380-37-0), (4-(3,6-dibromo-9H-carbazole-9-yl)butyl]phosphonic acid (BrMeOPh-4PACz, CAS No. 3053380-37-0), (4-(3,6-dichloro ...6-Di-tert-butyl-9H-carbazole-9-yl)butyl)phosphonic acid (tBu-4PACz, CAS No. 3023627-39-3), [4-(7H-dibenzocarbazole-7-yl)butyl]phosphonic acid (4PADCB, CAS No. 2882156-63-8), [4-(2,7-dibromo-9,9-dimethylacridin-10(9-hydro)-yl)butyl]phosphonic acid (2Br-4DMAcPA / At least one of DMAcPA (CAS No. 2971088-37-4), 2-(3,7-dibromo-10H-phenthiazin-10-yl)ethyl]phosphonic acid (Br-2EPT, CAS No. 2826271-17-2), and (2-(4-(bis(4-methoxyphenyl)amino)phenyl)-1-cyanovinyl)phosphonic acid (MPA-CPA, CAS No. 2212003-31-9).

[0011] In some optional embodiments of the first aspect of this application, the material of the transparent conductive layer includes, but is not limited to, indium tin oxide (ITO), indium zinc oxide (IZO), tungsten-doped indium oxide (IWO), zirconium-doped indium oxide (IZrO), fluorine-doped tin oxide (FTO), aluminum-doped zinc oxide (AZO), antimony-doped tin oxide (ATO), and gallium-doped zinc oxide (GZO). The preparation method includes, but is not limited to, magnetron sputtering (PVD) and reactive plasma deposition (RPD). The thickness of the transparent conductive layer is 20 nm to 100 nm.

[0012] A second aspect of this application provides a method for preparing a perovskite solar cell, comprising: A substrate is provided, on which a transparent conductive layer is disposed; A hole transport layer was obtained by using a wet coating process to prepare a self-assembled monolayer and nano-sized Lewis acid-base catalytic particles dispersed in the self-assembled monolayer on the side of the transparent conductive layer away from the substrate. A perovskite light-absorbing layer and an electron transport layer are sequentially fabricated on the hole transport layer.

[0013] In some optional embodiments of the second aspect of this application, a wet coating process is used to prepare a self-assembled monolayer and nano-sized Lewis acid-base catalytic particles dispersed in the self-assembled monolayer on the surface of the transparent conductive layer away from the substrate, including: Lewis acid-base catalysts are dispersed or dissolved in a solvent to obtain a dispersion system; A first annealing treatment is then performed to obtain dispersed nano-sized Lewis acid-base catalytic particles; A self-assembled monolayer is obtained by coating a transparent conductive layer with nano-sized Lewis acid-base catalytic particles, followed by a second annealing treatment. The nano-sized Lewis acid-base catalytic particles are dispersed in the self-assembled monolayer.

[0014] The solvent for the dispersion system is selected from at least one of ethanol, isopropanol, and methanol. The Lewis acid-base catalyst includes at least one of alumina, aluminum chloride, silica, aluminum sulfate, ferric chloride, magnesium oxide, and calcium oxide. Alumina, silica, aluminum sulfate, magnesium oxide, and calcium oxide are poorly soluble in solvents such as ethanol, isopropanol, and methanol, and are therefore dispersed in the solvent of the dispersion system. Aluminum chloride and ferric chloride exist in both anhydrous and hydrated forms. Anhydrous aluminum chloride and anhydrous ferric chloride have high solubility in solvents such as ethanol, isopropanol, and methanol, and are therefore dissolved in the solvent of the dispersion system. Hydrated aluminum chloride and hydrated ferric chloride contain water of crystallization and have low solubility in solvents such as ethanol, isopropanol, and methanol, and are therefore mostly dispersed in the solvent of the dispersion system.

[0015] In some optional embodiments of the second aspect of this application, a wet coating process is used to prepare a self-assembled monolayer and nano-sized Lewis acid-base catalytic particles dispersed in the self-assembled monolayer on the surface of the transparent conductive layer away from the substrate, including: A self-assembled monomolecular solution containing Lewis acid-base catalysts is coated on the side of the transparent conductive layer away from the substrate, followed by a third annealing treatment to obtain a self-assembled monolayer and nano-sized Lewis acid-base catalyst particles dispersed in the self-assembled monolayer.

[0016] In some optional embodiments of the second aspect of this application, the mass ratio of the self-assembled monomolecular material to the Lewis acid-base catalyst in the self-assembled monomolecular solution is 1:(0.005~0.01). Exemplarily, the mass ratio of the self-assembled monomolecular material to the Lewis acid-base catalyst in the self-assembled monomolecular solution is 1:0.005, 1:0.008, or 1:0.01. In some optional embodiments of the second aspect of this application, the concentration of the self-assembled monomolecular material in the self-assembled monomolecular solution is 0.5~3 mg / mL. Exemplarily, the concentration of the self-assembled monomolecular material in the self-assembled monomolecular solution is 0.5 mg / mL, 0.75 mg / mL, 1 mg / mL, 1.25 mg / mL, 1.5 mg / mL, 1.75 mg / mL, 2 mg / mL, 2.25 mg / mL, 2.5 mg / mL, 2.75 mg / mL, or 3 mg / mL.

[0017] In some optional embodiments of the second aspect of this application, the annealing conditions in the perovskite solar cell fabrication method are annealing on a hot plate at 70°C to 150°C for 2 to 30 minutes, and the annealing process includes a first annealing process, a second annealing process, and a third annealing process. Exemplarily, the annealing temperature can be 70°C, 80°C, 90°C, 100°C, 110°C, 120°C, 130°C, 140°C, or 150°C, and the annealing time can be 2 min, 5 min, 10 min, 15 min, 20 min, 25 min, or 30 min.

[0018] A third aspect of this application provides a photovoltaic module comprising: at least one cell string, the cell string comprising at least two perovskite cells as described in the first aspect, or at least two perovskite cells prepared by the method described in the second aspect.

[0019] Beneficial effects: The perovskite solar cell and its preparation method, as well as the photovoltaic module provided in this application, introduce dispersed nano-sized Lewis acid-base catalytic particles into the self-assembled monolayer of the hole transport layer. These Lewis acid-base catalytic particles possess high specific surface area and a high density of Lewis acid and / or Lewis base catalytic active sites, and play the following roles: 1. Activating anchoring groups: Lewis acid sites on the surface of nanoparticles can combine with anchoring groups of self-assembled monomolecules (such as oxygen atoms in phosphate groups), causing their electron clouds to shift, bond lengths to lengthen, and making them easier to break or recombine. 2. Activating the substrate surface: Lewis base sites on the surface of nanoparticles can capture protons from hydroxyl groups on the TCO surface, generating more nucleophilic surface oxygen anions, which greatly improves the reactivity of anchoring groups with hydroxyl groups on the transparent conductive layer surface.

[0020] In summary, the technical solution provided in this application, by introducing dispersed nano-sized Lewis acid-base catalytic particles into the self-assembled monolayer, can catalyze and promote the dehydration reaction between the anchoring groups in the self-assembled monolayer and the hydroxyl groups on the surface of the transparent conductive layer, thereby reducing the activation energy of the interfacial bonding reaction, thus improving the coverage of the self-assembled monolayer on the transparent conductive layer and enhancing the photoelectric performance and stability of the perovskite solar cell.

[0021] The perovskite solar cell fabrication method provided in the second aspect of this application utilizes nano-sized Lewis acid-base catalytic particles during the wet coating process to form a self-assembled monolayer. These particles can capture the laterally spread self-assembled monomolecules on the transparent conductive layer surface at multiple points, increasing their nucleation rate across the substrate surface and making the nucleation sites more dense. This guides the self-assembled monomolecules to preferentially spread densely along the substrate surface, forming a dense monolayer structure. This effectively inhibits the aggregation, multilayer stacking, or localized aggregation of the self-assembled monomolecules. Therefore, by introducing nano-sized Lewis acid-base catalytic particles into the wet coating process, the self-assembled monomolecules can be more uniformly and firmly covered on the transparent conductive layer surface, significantly reducing pinhole defects and exposure of the transparent conductive layer. This improves the uniformity and integrity of the self-assembled monolayer coverage on the transparent conductive layer, thereby enhancing the photoelectric conversion efficiency and long-term stability of the perovskite solar cell. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a schematic diagram showing the coverage of self-assembled monomolecular materials in the present application technology and existing wet coating technology; Figure 2 The images are SEM scans of the battery cell precursors containing hole transport layers in Comparative Example 2 and Examples 5, 6, and 8 of this application, taken from a top-down view. Figure 3 This is a SEM scan of the battery cell precursor containing the hole transport layer in Embodiment 5 of this application, viewed from the side. Detailed Implementation

[0024] The technical solutions of this application will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0025] In the description of this application, it should be noted that the terms "first", "second", and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0026] Furthermore, the technical features involved in the different embodiments of this application described below can be combined with each other as long as they do not conflict with each other.

[0027] Self-Assembled Monolayers (SAMs) serve as the hole transport layer in perovskite solar cells. Their formation is based on the chemical bonding between the self-assembled monolayer material and the hydroxyl groups on the surface of the transparent conductive layer, as well as intermolecular interactions. The SAM material typically consists of anchoring groups, alkyl bridges, and terminal groups. Anchoring groups exist in the form of active functional groups such as phosphonic acid groups (-PO(OH)2), carboxyl groups (-COOH), hydroxyl groups (-OH), and thiol groups (-SH), which can form covalent bonds, coordinate bonds, or hydrogen bonds with the surface of the transparent conductive layer, thus achieving strong anchoring. Terminal groups exist in the form of conjugated structures such as carbazole groups, dibenzocarbazole groups, acridine groups, phenothiazine groups, or phenyl groups. Their π-electron clouds can compensate for the charge of halogen vacancies in the perovskite light-absorbing layer, thereby filling the shallow energy level defects caused by halogen vacancies. Substituents can be further introduced onto the terminal groups. Substituents can regulate the electron cloud density of the terminal groups, enhance their coordination strength with uncoordinated divalent cations, and improve defect passivation efficiency. Alkyl bridges are the "backbone" that connects anchoring groups and terminal groups, and are usually composed of saturated carbon chains.

[0028] During wet coating, the spreading, adsorption, and bonding of self-assembled monomolecules on the surface of the transparent conductive layer all require a certain reaction time and activation energy. During this process, π-π stacking interactions, van der Waals forces, and hydrophobic alkyl chain interactions exist between the molecules of the self-assembled monomolecules. This makes the molecules of the self-assembled monomolecules more inclined to adsorb and aggregate together, rather than preferentially bonding with the hydroxyl groups on the surface of the transparent conductive layer. This results in uneven distribution of the self-assembled monomolecules on the surface of the transparent conductive layer, leading to areas on the surface of the transparent conductive layer being exposed due to gaps in the hole transport layer, resulting in pinholes in the hole transport layer.

[0029] Currently, in order to improve the coverage of self-assembled monomolecules, the transparent conductive layer is usually surface-treated to generate more hydroxyl groups on the surface of the transparent conductive layer. However, this method only increases the bonding sites of the self-assembled monomolecules on the surface of the transparent conductive layer, and cannot completely solve the problem of poor binding between the self-assembled monomolecules and the hydroxyl groups on the surface of the transparent conductive layer due to the aggregation of the self-assembled monomolecules themselves.

[0030] In view of this, this application proposes a perovskite solar cell with enhanced bonding ability between self-assembled single-molecule materials and transparent conductive layers, a method for preparing the same, and a photovoltaic module.

[0031] The first aspect of this application provides a perovskite solar cell, including a substrate and a transparent conductive layer, a hole transport layer, a perovskite light-absorbing layer and an electron transport layer stacked on the substrate, wherein the hole transport layer includes a self-assembled monolayer and nano-sized Lewis acid-base catalytic particles dispersed in the self-assembled monolayer.

[0032] The perovskite solar cells provided in the first aspect of this application include single-junction perovskite solar cells and tandem perovskite solar cells.

[0033] Single-junction perovskite solar cells include rigid single-junction perovskite solar cells and flexible perovskite solar cells. The substrate materials of rigid single-junction perovskite solar cells include, but are not limited to, soda-lime glass and borosilicate glass, with a substrate thickness of 0.5 mm to 5 mm. The substrate materials of flexible single-junction perovskite solar cells include, but are not limited to, polyimide (PI), polyester (PET), or polyethylene naphthalate (PEN).

[0034] The substrate of the tandem perovskite solar cell is the base cell substrate, which is selected from crystalline silicon base cells, CIGS thin film base cells, cadmium telluride thin film base cells, III V thin film base cells, or perovskite base cells.

[0035] When the perovskite solar cell is a tandem perovskite solar cell, the hole transport layer, the perovskite light-absorbing layer, and the electron transport layer disposed on the side of the transparent conductive layer away from the substrate constitute the perovskite top cell. The transparent conductive layer, as a composite layer between the bottom cell and the top cell, can realize the electrical series connection between the top cell and the bottom cell, efficient carrier recombination and transport, energy level matching and optical control, reduce interface loss, and improve the photoelectric conversion efficiency and stability of the tandem solar cell.

[0036] Furthermore, the crystalline silicon solar cell includes an N-type monocrystalline silicon substrate, a P-type amorphous silicon thin film (P-side) deposited on one side of the N-type monocrystalline silicon substrate, a transparent conductive oxide layer, and a back electrode, and an N-type amorphous silicon thin film (N-side) deposited on the other side of the N-type monocrystalline silicon substrate. The transparent conductive layer is disposed on the side of the N-type amorphous silicon thin film away from the N-type monocrystalline silicon substrate. The monocrystalline silicon substrate has a thickness of 80 μm to 220 μm and is mainly used to absorb light and generate charge carriers (holes and electrons). The P-type amorphous silicon thin film has a thickness of 5 nm to 30 nm, and the N-type amorphous silicon thin film has a thickness of 5 nm to 30 nm. The P-type and N-type amorphous silicon thin films form a PN junction, generating a built-in electric field to separate electrons and holes. The transparent conductive oxide layer has a thickness of 15 nm to 60 nm, and the back electrode has a thickness of 2 μm to 30 μm. The transparent conductive oxide layer and the back electrode are mainly used to collect and conduct current.

[0037] like Figure 1As shown, existing wet coating techniques for preparing self-assembled monomolecular hole transport layers on transparent conductive layers (TCOs) generally suffer from problems such as insufficient molecular density of the self-assembled monomolecular materials, missing coverage in local areas, and low overall surface coverage. This application's technology introduces Lewis acid-base catalytic particles during the preparation of the self-assembled monomolecular hole transport layer on the TCO surface, significantly improving the coverage of the self-assembled monomolecular materials on the transparent conductive layer and resulting in a more dense molecular arrangement, demonstrating a clear advantage over conventional techniques.

[0038]

Example 1

[0039] Alumina nanoparticles with an average particle size of 10 nm were dispersed in isopropanol to obtain a dispersion system with a concentration of 0.01 mg / mL. The dispersion system was then spin-coated onto an indium tin oxide (ITO) transparent conductive layer. The spin-coated battery precursor structure was then annealed on a hot plate at 100 °C for 10 minutes to form dispersed nano-sized alumina nanoparticles on the indium tin oxide (ITO) transparent conductive layer. 1.2 Preparation of Self-Assembled Monolayer: 4-PADCB (4-(7H-dibenzocarbazole-7-yl)butylphosphonic acid, CAS No. 2882156-63-8) was prepared into a 1 mg / mL self-assembled monolayer solution using ethanol. The self-assembled monolayer solution was spin-coated at 3000 rpm onto the indium tin oxide (ITO) transparent conductive layer containing alumina nanoparticles formed in step 1.1. The spin-coating was continued for 30 s, and the resulting battery precursor structure was immediately placed on a hot plate at 100 ℃ for 10 minutes of annealing to form a 1 nm thick self-assembled monolayer. Nano-sized alumina particles were dispersed within the self-assembled monolayer, constituting the hole transport layer. By controlling the volume of the dispersion system spin-coated onto the transparent conductive layer to be the same as the volume of the self-assembled monolayer solution, the mass ratio of the self-assembled monolayer to alumina particles in the hole transport layer was controlled to be approximately 1:0.01.

[0040] 2. Preparation of perovskite light-absorbing layer: First, prepare a 1.7M perovskite precursor solution. Spin-coat the perovskite precursor solution onto the hole transport layer at 2500 rpm and 5500 rpm for 25 s and 12 s respectively. At 25 s, slowly drop 300 μL of the antisolvent chlorobenzene. Then place it on a hot stage at 100℃ and heat for annealing for 30 min to form a perovskite light-absorbing layer. 3. Preparation of passivation layer: The passivation material PDAI2 (1,3-diaminopropane dihydroiodate, CAS No.: 120675-53-8) was mixed with isopropanol to obtain a passivation solution. The concentration of PDAI2 was 0.3 mg / mL. The passivation solution was coated on the surface of the perovskite light-absorbing layer and annealed at 100°C for 8 minutes to obtain the passivation layer. 4. Preparation of electron transport layer: A 12 nm thick C60 layer is deposited on the surface of the passivation layer using a thermal evaporation process at a deposition rate of 1 Å / s to form an electron transport layer; 5. Preparation of tin oxide buffer layer: A 20 nm thick tin oxide buffer layer is deposited on the surface of the electron transport layer on the side facing away from the passivation layer using atomic layer deposition technology; 6. Preparation of silver electrode: A 120 nm thick silver electrode gate line is deposited on the surface of the tin oxide buffer layer on the side opposite to the electron transport layer using a thermal evaporation process.

[0041]

Example 2

[0042]

Example 3

[0043]

Example 4

[0044]

Example 5

[0045] The fabrication method of the perovskite tandem solar cell provided in this embodiment is as follows: 1. Preparation of hole transport layer: Using a spin coater, ethanol was spin-coated onto the indium tin oxide (ITO) transparent conductive layer on the N side of the crystalline silicon bottom cell at a speed of 3000 rpm for 30 s, and repeated twice. Then, the layer was heat-treated at 200℃ for 10 min to complete the cleaning.

[0046] Silica nanoparticles with an average particle size of 15 nm were dispersed in a self-assembled monomolecular solution. The self-assembled monomolecular solution was obtained by mixing 4PACz ([4-(9H-carbazole-9-yl)ethyl]phosphoric acid, CAS No.: 2747959-96-0) and isopropanol, with a concentration of 1 mg / mL of 4PACz and a mass ratio of 4PACz to silica nanoparticles of 1:0.01. A self-assembled monomolecular solution containing dispersed silicon oxide nanoparticles was spin-coated onto an indium tin oxide (ITO) transparent conductive layer at a rotation speed of 3000 rpm for 30 seconds. The resulting battery precursor structure was then immediately placed on a hot stage at 100 °C for 10 minutes of annealing to form a self-assembled monomolecular layer with a thickness of 1 nm. The silicon oxide nanoparticles were dispersed in the self-assembled monomolecular layer, forming a hole transport layer. Other operations were the same as in Example 1.

[0047] 2. Preparation of perovskite light-absorbing layer: First, prepare a 1.7M perovskite precursor solution. Spin-coat the perovskite precursor solution onto the hole transport layer at 2500 rpm and 5500 rpm for 25 s and 12 s respectively. At 25 s, slowly drop 300 μL of the antisolvent chlorobenzene. Then place it on a hot stage at 100℃ and heat for annealing for 30 min to form a perovskite light-absorbing layer. 3. Preparation of passivation layer: The passivation material PDAI2 (1,3-diaminopropane dihydroiodate, CAS No.: 120675-53-8) was mixed with isopropanol to obtain a passivation solution. The concentration of PDAI2 was 0.3 mg / mL. The passivation solution was coated on the surface of the perovskite light-absorbing layer and annealed at 100°C for 8 minutes to obtain the passivation layer. 4. Preparation of electron transport layer: A 12 nm thick C60 layer is deposited on the surface of the passivation layer using a thermal evaporation process at a deposition rate of 1 Å / s to form an electron transport layer; 5. Preparation of tin oxide buffer layer: A 20 nm thick tin oxide buffer layer is deposited on the surface of the electron transport layer on the side facing away from the passivation layer using atomic layer deposition technology; 6. Preparation of silver electrode: A 120 nm thick silver electrode gate line is deposited on the surface of the tin oxide buffer layer on the side opposite to the electron transport layer using a thermal evaporation process.

[0048]

Example 6

[0049]

Example 7

[0050]

Example 8

[0051] Comparative Example 1 Compared to Example 1, the hole transport layer of the single-junction perovskite solar cell provided in Comparative Example 1 comprises a self-assembled monolayer, and steps 1.1 and 1.2 of preparing the hole transport layer in Example 1 are replaced by the following operations: Using a spin coater, a 1×1cm... 2 The substrate was ultrasonically cleaned sequentially by immersion in ethanol, detergent, ultrapure water, isopropanol, and ethanol. The substrate was then dried with nitrogen gas. The volume of solvent used for ultrasonic cleaning was 500 mL, and the ultrasonic cleaning time was 15 minutes each time.

[0052] The self-assembled monomolecular material 4-PADCB (4-(7H-dibenzocarbazole-7-yl)butyl)phosphonic acid, CAS No. 2882156-63-8) was prepared into a self-assembled monomolecular solution with a concentration of 1 mg / mL using ethanol solvent. The self-assembled monomolecular solution was spin-coated onto an indium tin oxide (ITO) transparent conductive layer at a speed of 3000 rpm for 30 s. The resulting battery precursor structure was then immediately placed on a hot plate at 100 °C for 10 minutes of annealing to form a 1 nm thick self-assembled monomolecular layer as a hole transport layer; other operations were the same as in Example 1.

[0053] Comparative Example 2 Compared to Example 5, the hole transport layer of the perovskite tandem solar cell provided in Comparative Example 2 comprises a self-assembled monolayer, and the following operation replaces the steps for preparing the hole transport layer in Example 5: Using a spin coater, ethanol was spin-coated onto the indium tin oxide (ITO) transparent conductive layer on the N-side of the crystalline silicon bottom cell at a speed of 3000 rpm for 30 seconds, repeated twice, and then heat-treated at 200℃ for 10 minutes to complete the cleaning.

[0054] A self-assembled monomolecular material, 4PACz ([4-(9H-carbazole-9-yl)ethyl]phosphate, CAS No.: 2747959-96-0), was mixed with isopropanol to obtain a self-assembled monomolecular solution with a concentration of 1 mg / mL. The self-assembled monomolecular solution was spin-coated onto an indium tin oxide (ITO) transparent conductive layer at 3000 rpm for 30 s. The resulting battery precursor structure was then immediately placed on a hot plate at 100 °C for 10 minutes of annealing to form a 1 nm thick self-assembled monomolecular layer as a hole transport layer; other operations were the same as in Example 5.

[0055] The efficiency of the perovskite solar cells prepared in Examples 1 to 8 and Comparative Examples 1 and 2 was tested, and the test results are shown in Table 1 below.

[0056] Table 1

[0057] The comparison results between Examples 1 to 4 and Comparative Example 1, and between Examples 5 to 8 and Comparative Example 2, show that in perovskite solar cells, using a self-assembled monolayer with dispersed nano-sized Lewis acid-base catalytic particles as a hole transport layer can significantly improve the open-circuit voltage and fill factor, increase the short-circuit current density, and thus improve the photoelectric conversion efficiency of the perovskite solar cell. This demonstrates that when preparing the self-assembled monolayer using a wet process, introducing nano-sized Lewis acid-base catalytic particles can reduce the activation energy of the interfacial bonding reaction between the self-assembled monolayer and the transparent conductive layer, which is beneficial for the lateral uniform and dense spreading of the self-assembled monolayer material on the surface of the transparent conductive layer, inhibiting agglomeration and other issues, effectively improving the coverage of the self-assembled monolayer material on the transparent conductive layer, thereby enhancing the performance of the perovskite solar cell.

[0058] The hole transport layers of Comparative Example 2, Examples 5, 6, and 8 were characterized by SEM (Scanning Electron Microscope) scanning using a Thermo Fisher Scientific microscope.

[0059] from Figure 2 As can be seen from SEM scan image a (Comparative Example 2), since self-assembled monomolecules are composed of individual molecules, the thickness of the self-assembled monolayer is typically less than 5 nanometers. Under SEM, almost no obvious undulations, particles, or pores are visible. Figure 2 b、 Figure 2 c. Figure 2 As shown in d (SEM scans of Examples 5, 6, and 8), after introducing catalysts such as silica and ferric chloride during the wet preparation of self-assembled monolayers, dispersed catalytic particles can be clearly observed under SEM. (Comparison) Figure 2 b、 Figure 2 c and Figure 2 As can be seen from d, whether insoluble catalytic particles (silicon oxide) or soluble catalytic particles (ferric chloride) are used, nano-sized catalytic particles dispersed in a self-assembled monolayer can be formed.

[0060] Figure 3 Example 5 shows the dispersion of Lewis acid-base catalytic particles in a self-assembled monolayer from a side view. Figure 3 It can be seen that the silicon substrate of the concentrated solar cell precursor has a textured structure. Similarly, the SAM layer structure cannot be observed in SEM scanning due to the thin thickness of the self-assembled monolayer. Figure 3 The distribution of Lewis acid-base catalytic particles can be clearly seen in the image.

[0061] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A perovskite solar cell, characterized in that, The invention includes a substrate and a transparent conductive layer, a hole transport layer, a perovskite light-absorbing layer, and an electron transport layer stacked on the substrate. The hole transport layer comprises a self-assembled monolayer and nano-sized Lewis acid-base catalytic particles dispersed in the self-assembled monolayer.

2. The perovskite solar cell according to claim 1, characterized in that, The Lewis acid-base catalytic particles have a particle size of 5 nm to 20 nm; And / or, the Lewis acid-base catalytic particles include at least one of alumina, aluminum chloride, silicon dioxide, aluminum sulfate, ferric chloride, magnesium oxide, and calcium oxide.

3. The perovskite solar cell according to claim 1, characterized in that, The mass ratio of the self-assembled monolayer to the Lewis acid-base catalytic particles is 1:(0.005~0.01).

4. The perovskite solar cell according to claim 1, characterized in that, The materials of the self-assembled monolayer include [2-(9H-carbazole-9-yl)ethyl]phosphonic acid, [2-(3,6-dimethyl-9H-carbazole-9-yl)ethyl]phosphonic acid, (2-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl)phosphonic acid, [2-(3,6-diphenyl-9H-carbazole-9-yl)ethyl]phosphonic acid, [2-(3,6-diiodo-9H-carbazole-9-yl)ethyl]phosphonic acid, and 2-(3,6-dibromo-9H-carbazole-9-yl)ethyl]phosphonic acid. [3,6-dichloro-9H-carbazole-9-yl)ethyl]phosphonic acid, 2-(3,6-difluoro-9H-carbazole-9-yl)ethyl]phosphonic acid, [2-(7H-dibenzocarbazole-7-yl)ethyl]phosphonic acid, [4-(9H-carbazole-9-yl)ethyl]phosphonic acid, [4-(3,6-dimethyl-9H-carbazole-9-yl)butyl]phosphonic acid, [4-(3,6-dimethoxy ... [3,6-Diphenyl-9H-carbazole-9-yl)butyl]phosphonic acid, [4-(3,6-diiodo-9H-carbazole-9-yl)butyl]phosphonic acid, [4-(3,6-dibromo-9H-carbazole-9-yl)butyl]phosphonic acid, (4-(3,6-dichloro-9H-carbazole-9-yl)butyl)phosphonic acid, (4-(3,6-difluoro-9H-carbazole-9-yl)butyl)phosphonic acid, [4-[3-bromo-6-(4-methoxyphenyl)-9H-carbazole-9-yl]butyl]phosphonic acid [4-(3,6-di-tert-butyl-9H-carbazole-9-yl)butyl]phosphonic acid, [4-(7H-dibenzocarbazole-7-yl)butyl]phosphonic acid, [4-(2,7-dibromo-9,9-dimethylacridin-10(9-hydro)-yl)butyl]phosphonic acid, 2-(3,7-dibromo-10H-phenthiazin-10-yl)ethyl]phosphonic acid, and at least one of (2-(4-(bis(4-methoxyphenyl)amino)phenyl)-1-cyanovinyl)phosphonic acid; And / or, the material of the transparent conductive layer includes, but is not limited to, indium tin oxide, indium zinc oxide, tungsten-doped indium oxide, zirconium-doped indium oxide, fluorine-doped tin oxide, aluminum-doped zinc oxide, antimony-doped tin oxide, and gallium-doped zinc oxide.

5. A method for preparing a perovskite solar cell, characterized in that, include: A substrate is provided, on which a transparent conductive layer is disposed; A hole transport layer is obtained by using a wet coating process to prepare a self-assembled monolayer and nano-sized Lewis acid-base catalytic particles dispersed in the self-assembled monolayer on the surface of the transparent conductive layer away from the substrate. A perovskite light-absorbing layer and an electron transport layer are sequentially fabricated on the hole transport layer.

6. The method for preparing a perovskite solar cell according to claim 5, characterized in that, The process employs a wet coating technique to prepare a self-assembled monolayer and nano-sized Lewis acid-base catalytic particles dispersed within the self-assembled monolayer on the surface of the transparent conductive layer away from the substrate, comprising: Lewis acid-base catalysts are dispersed or dissolved in a solvent to obtain a dispersion system; The dispersion system is coated on the side of the transparent conductive layer away from the substrate, and then subjected to a first annealing treatment to obtain dispersed nano-sized Lewis acid-base catalytic particles. A self-assembled monomolecular solution is coated on the surface of the nano-sized Lewis acid-base catalytic particles distributed in the transparent conductive layer, followed by a second annealing treatment to obtain a self-assembled monomolecular layer, in which the nano-sized Lewis acid-base catalytic particles are dispersed.

7. The method for preparing a perovskite solar cell according to claim 5, characterized in that, The process employs a wet coating technique to prepare a self-assembled monolayer and nano-sized Lewis acid-base catalytic particles dispersed within the self-assembled monolayer on the surface of the transparent conductive layer away from the substrate, comprising: A self-assembled monomolecular solution containing a Lewis acid-base catalyst is coated on the surface of the transparent conductive layer away from the substrate, followed by a third annealing treatment to obtain a self-assembled monomolecular layer and nano-sized Lewis acid-base catalyst particles dispersed in the self-assembled monomolecular layer.

8. The method for preparing a perovskite solar cell according to claim 7, characterized in that, In the self-assembled monomolecular solution, the mass ratio of the self-assembled monomolecular material to the Lewis acid-base catalyst is 1:(0.005~0.01). And / or, the Lewis acid-base catalyst includes alumina, aluminum chloride, silicon dioxide, aluminum sulfate, ferric chloride, magnesium oxide, and calcium oxide.

9. The method for preparing a perovskite solar cell according to any one of claims 6 to 8, characterized in that, The annealing process in the preparation method of perovskite solar cells is performed by annealing on a hot plate at 70°C to 150°C for 2 to 30 minutes. The annealing process includes the first annealing process, the second annealing process, and the third annealing process.

10. A photovoltaic module, characterized in that, include: At least one battery string, the battery string comprising at least two perovskite batteries as described in any one of claims 1 to 4, or at least two perovskite batteries prepared by the method as described in any one of claims 5 to 9.

Images