Perovskite cell and preparation method thereof, laminated cell and photovoltaic module

Abstract

The invention relates to the technical field of perovskite cells, provides a perovskite cell and a preparation method thereof, a laminated cell and a photovoltaic module, and at least facilitates the improvement of the efficiency of the perovskite cell and the reduction of the cost of HTMs. The perovskite cell comprises a transparent conductive substrate, a hole transport layer, a perovskite absorption layer, an electron transport layer and an electrode, the hole transport layer comprises a hole transport material, the chemical formula of the hole transport material is # imgabs0 #, and X is independently selected from O or S.

Description

Technical Field

[0001] This application relates to the technical field of perovskite solar cells, and particularly to a perovskite solar cell, a preparation method thereof, a tandem solar cell, and a photovoltaic module. Background Art

[0002] Perovskite solar cells (PSCs) are devices that use perovskite-type organometallic halide semiconductors as light-absorbing materials to directly convert light energy into electrical energy through the photovoltaic effect. The structure of perovskite solar cells mainly includes components such as a conductive substrate, an electron transport layer (ETL), a perovskite layer, a hole transport layer (HTL), and a metal electrode.

[0003] The hole transport layer plays a crucial role in hole extraction and transport, suppressing carrier recombination, and improving the crystallization and film formation of perovskite materials. Therefore, continuously developing hole transport materials (HTMs) with excellent film-forming properties, solvent resistance, thermal stability, hole mobility, and energy levels matching those of perovskite materials is a key factor in fabricating efficient and stable perovskite solar cells.

[0004] Currently, how to develop high-efficiency and low-cost HTMs has become an important research topic. Summary of the Invention

[0005] Embodiments of this application provide a perovskite solar cell, a preparation method thereof, a tandem solar cell, and a photovoltaic module, which are at least beneficial to improving the efficiency of perovskite solar cells while reducing the cost of HTMs.

[0006] According to some embodiments of this application, on the one hand, embodiments of this application provide a perovskite solar cell, which includes a transparent conductive substrate, a hole transport layer, a perovskite absorption layer, an electron transport layer, and an electrode. Among them, the hole transport layer includes a hole transport material, and the chemical formula of the hole transport material is as follows:

[0007]

[0008] Wherein, each X is independently selected from O or S.

[0009] According to some embodiments of the present application, on the other hand, an embodiment of the present application further provides a method for preparing a perovskite battery, including: sequentially forming a hole transport layer, a perovskite absorption layer, an electron transport layer, and an electrode on a transparent conductive substrate, wherein the preparation steps of the hole transport layer include: configuring the hole transport material as described in the above embodiments into a solution and then coating it on the transparent conductive substrate. The preparation steps of the hole transport material are as follows: adding a first compound, a second compound, tetrakis(triphenylphosphine)palladium, and potassium carbonate to a solvent, the solvent being toluene, ethanol, and water, and the volume ratio of toluene, ethanol, and water being 2:1:1, reacting at 80°C to 90°C for 6h to 12h, cooling to room temperature, extracting the organic phase with DCM, drying the organic phase with anhydrous Mg2SO4, filtering, and performing vacuum distillation to obtain a third compound; the chemical formula of the first compound is:

[0010] Each X is independently selected from O or S;

[0011] The chemical formula of the second compound is:

[0012]

[0013] Dissolve the third compound in 1,4-dioxane at 25°C, add trimethylsilyl bromide dropwise, and stir for 10h to 16h. After removing the solvent by vacuum distillation, the obtained solid powder is dissolved in methanol at room temperature, and deionized water is added dropwise until the mixture becomes opaque. Continue to stir for 10h to 16h. The filtered and washed crude product is dissolved in tetrahydrofuran and precipitated in acetone to obtain the hole transport material.

[0014] In some embodiments, the molar ratio of the first compound, the second compound, tetrakis(triphenylphosphine)palladium, and potassium carbonate is 1:(2.2 - 2.5):(0.03 - 0.1):(5 - 7).

[0015] In some embodiments, the molar ratio of the third compound to trimethylsilyl bromide is 1:(8 - 15).

[0016] In some embodiments, the preparation steps of the first compound include: preparing a first product, dissolving raw material I, 2-thiopheneboronic acid, tetrakis(triphenylphosphine), and potassium carbonate in a solvent, reacting at 85°C to 95°C for 8h to 12h, cooling to room temperature, extracting the organic phase with dichloromethane, drying the organic phase with anhydrous Mg2SO4, filtering, and performing vacuum distillation to obtain the first product;

[0017] The chemical formula of raw material I is:

[0018]

[0019] Dissolve the first product in tetrahydrofuran, stir at -70°C to -80°C for 10 min to 20 min, dropwise add n-butyllithium and react at -70°C to -80°C for 1 h to 2 h. Then add bis(pinacolato)diboron and continue to react at -70°C to -80°C for 1 h to 2 h. Subsequently, react at room temperature for 10 h to 16 h. Extract the organic phase with dichloromethane, dry the organic phase with anhydrous Mg2SO4, filter, and perform vacuum distillation to obtain the first compound.

[0020] In some embodiments, the molar ratio of raw material I, 2-thiopheneboronic acid, tetrakis(triphenylphosphine), and potassium carbonate is 1:(1.1 - 1.5):(0.05 - 0.1):(2.5 - 4); the molar ratio of the first product, n-butyllithium, and bis(pinacolato)diboron is 1:(1.1 - 1.3):(1.2 - 1.5).

[0021] In some embodiments, the preparation steps of the second compound include: preparing the second product by dissolving raw material II, tetrabutylammonium bromide, and potassium hydroxide in 1,4-dibromobutane for a substitution reaction, reacting at 65°C to 70°C for 12 h to 24 h, quenching with water after the reaction, extracting the organic phase with dichloromethane, drying the organic phase with anhydrous Mg2SO4, filtering, and performing vacuum distillation to obtain the second product;

[0022] The chemical formula of raw material II is:

[0023] Each X is independently selected from O or S;

[0024] React the second product with triethyl phosphite at 140°C to 150°C for 12 h to 16 h, and perform vacuum distillation to obtain the second compound.

[0025] In some embodiments, the molar ratio of raw material II, tetrabutylammonium bromide, potassium hydroxide, and 1,4-dibromobutane is 1:(0.1 - 0.2):(5 - 10):(50 - 150); the molar ratio of the second product to triethyl phosphite is 1:(25 - 50).

[0026] According to some embodiments of the present application, on the other hand, an embodiment of the present application provides a tandem cell, including: a top cell, which is the perovskite cell in the above embodiments; a crystalline silicon bottom cell, which is located on the side of the transparent conductive substrate of the perovskite cell away from the electrode.

[0027] According to some embodiments of the present application, on yet another aspect, an embodiment of the present application provides a photovoltaic module, including: a plurality of tandem cells as in the above embodiments; a connecting member for connecting adjacent tandem cells; a glue film covering the surface of the tandem cells; and a cover plate located on the surface of the glue film away from the tandem cells.

[0028] The technical solution provided by the embodiment of the present application has at least the following advantages:

[0029] The perovskite battery provided by the embodiment of the present application includes a transparent conductive substrate, a hole transport layer, a perovskite absorption layer, an electron transport layer, and an electrode. Among them, the hole transport layer includes a hole transport material 4PA-POZ or 4PA-PTZ. 4PA-POZ or 4PA-PTZ has phenothiazine (PTZ) or phenoxazine (POZ) as the core and triphenylamine as the end group. The group containing a sulfur atom in the molecule endows the HTMs with appropriate energy levels to increase intra- and / or intermolecular interactions, as well as enhanced buried interface interactions with quasi-two-dimensional layered perovskites, making the mobility of the hole transport material better, which is beneficial to the extraction and transport of holes. Moreover, the hole transport material has a HOMO energy level that matches the perovskite and is relatively deep, with a high decomposition temperature and good thermal stability. 4PA-POZ or 4PA-PTZ has good solubility in organic solvents, good film-forming properties, good wettability with the perovskite precursor solvent, which helps the crystallization and film formation of perovskite. It can be used in inverted quasi-two-dimensional perovskite solar cells without doping any additives and has good application prospects. Description of the Drawings

[0030] One or more embodiments are illustrated by way of example with reference to the pictures in the corresponding drawings. These exemplary illustrations do not limit the embodiments unless otherwise stated. The figures in the drawings do not constitute a scale limitation; in order to more clearly illustrate the technical solutions in the embodiments of the present application or in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0031] Figure 1 Schematic diagram of a perovskite battery structure provided by the embodiment of the present application;

[0032] Figure 2 1H NMR spectrum corresponding to 4PA-POZ;

[0033] Figure 3 1H NMR spectrum corresponding to 4PA-PTZ. Detailed Description of the Embodiments

[0034] As can be seen from the background art, how to develop high-efficiency and low-cost HTMs has become an important research topic.

[0035] The perovskite materials in PSCs are very sensitive to moisture and heat. During the operation of perovskite solar cells, the decomposition of the perovskite absorption layer will occur, and the stability of perovskite solar cells will be damaged. For inverted PSCs, the HTL is deposited on the surface of the conductive substrate prior to the perovskite absorption layer and can be used to regulate the growth of perovskite crystals and interfacial properties. Therefore, it plays a crucial role in the preparation of high-efficiency devices.

[0036] Currently, HTMs in perovskite solar cells are mainly divided into three categories: inorganic hole transport materials, organic small molecule hole transport materials, and organic polymer hole transport materials. Small molecule HTMs have a definite structure and molecular weight. According to the spatial structure, they can be roughly divided into three categories: linear structure, spiro structure, and star structure. They can also be divided into dithienopyrrole type, triphenylamine type, carbazole type, bifluorene type, thiophene type, etc. according to the different groups contained in the molecular structure. Small molecule HTMs have become the most common type of HTMs in perovskite solar cells due to their advantages such as a variety of synthetic varieties, adjustable properties, high purity, and easy solution processing. However, due to their rigid structure, they have low tolerance to perovskite precursor solutions. The films produced by small molecule HTMs always have morphological defects such as pinholes, and are morphologically unstable under external stimuli. Moreover, many small molecule HTMs require the addition of dopants, and these factors also pose obstacles to the large-scale commercialization of PSCs.

[0037] Introducing sulfur-containing functional groups into HTMs can improve the planarity and conductivity of molecules. Sulfur can also coordinate with Pb 2+ atoms and passivate defects at the surface and grain boundaries. The two commonly used sulfur functional groups are thiophene and methylthio groups. Phenothiazine (PTZ) and phenoxazine (POZ) are molecules with a nearly planar ternary heterocyclic structure, and the dihedral angles are approximately 169° and 153° respectively. They are common functional materials in PSCs. However, there are still few reports on their application fields in small molecule HTMs.

[0038] The embodiments of the present application provide a perovskite solar cell, its preparation method, a tandem solar cell, and a photovoltaic module. The hole transport layer in the perovskite solar cell includes hole transport materials 4PA-POZ and 4PA-PTZ. 4PA-POZ and 4PA-PTZ are centered on POZ or PTZ. Under the guidance of reaction mechanisms such as Suzuki-Miyaura type C-C coupling, small molecule HTMs centered on phenothiazine (PTZ) or phenoxazine (POZ) and with thiophene triphenylamine as the end group are constructed, which is at least beneficial to improving the efficiency of perovskite solar cells while reducing the cost of HTMs.

[0039] In the description of the embodiments of the present application, technical terms such as "first" and "second" are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity, specific order, or primary-secondary relationship of the indicated technical features.

[0040] In the description of the embodiments of the present application, the meaning of "a plurality of" is more than two, unless otherwise specifically defined.

[0041] Referring to "embodiments" herein means that the specific features, structures, or characteristics described in connection with the embodiments may be included in at least one embodiment of the present application. The phrase appears in various places in the specification and does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art will explicitly and implicitly understand that the embodiments described herein may be combined with other embodiments.

[0042] In the description of the embodiments of the present application, when a component "comprises" another component, unless otherwise specified, other components are not excluded, and other components may further be included.

[0043] The terms used in the description of the various embodiments herein are only for the purpose of describing specific embodiments and are not intended to be limiting. As used in the description of the various embodiments and the appended claims, "component" is also intended to include the plural form, unless the context clearly indicates otherwise.

[0044] The embodiments of the present application will be described in detail below with reference to the accompanying drawings. However, those of ordinary skill in the art can understand that in the embodiments of the present application, many technical details are provided for the reader to better understand the present application. However, even without these technical details and various changes and modifications based on the following embodiments, the technical solutions claimed in the present application can still be implemented.

[0045] Figure 1 Schematic diagram of a perovskite battery structure provided for the embodiments of the present application.

[0046] According to some embodiments of the present application, on the one hand, the embodiments of the present application provide a perovskite battery. Referring to Figure 1 , the perovskite battery includes a transparent conductive substrate, a hole transport layer, a perovskite absorption layer, an electron transport layer, and an electrode. Among them, the hole transport layer includes a hole transport material, and the chemical formula of the hole transport material is as follows:

[0047]

[0048] Among them, each X is independently selected from O or S.

[0049] For example, the hole transport material is 4PA-POZ, and the chemical formula of 4PA-POZ is as follows:

[0050]

[0051] Alternatively, the hole transport material is 4PA-PTZ, and the chemical formula of 4PA-PTZ is as follows:

[0052]

[0053] Figure 2 is the 1H NMR spectrum corresponding to 4PA-POZ; Figure 3 is the 1H NMR spectrum corresponding to 4PA-PTZ.

[0054] The perovskite solar cell provided by the embodiment of the present application includes a transparent conductive substrate, a hole transport layer, a perovskite absorption layer, an electron transport layer, and an electrode. Among them, the hole transport layer includes a hole transport material 4PA-POZ or 4PA-PTZ. 4PA-POZ or 4PA-PTZ takes phenothiazine (PTZ) or phenoxazine (POZ) as the core and thiophene trianiline as the end group. The group containing a sulfur atom in the molecule endows the HTMs with appropriate energy levels to increase intra- and / or intermolecular interactions, as well as enhanced buried interface interactions with quasi-two-dimensional layered perovskites, resulting in good mobility of the hole transport material, which is beneficial to the extraction and transport of holes. Moreover, the hole transport material has a HOMO energy level that matches the perovskite and is relatively deep, with a high decomposition temperature and good thermal stability. 4PA-POZ or 4PA-PTZ has good solubility in organic solvents, good film-forming properties, good wettability with the perovskite precursor solvent, and is helpful for the crystallization and film formation of perovskites. It can be used in inverted quasi-two-dimensional perovskite solar cells without doping any additives and has good application prospects.

[0055] The material of the transparent conductive substrate includes ITO glass, which is processed by depositing a layer of indium tin oxide (commonly known as ITO) film on the basis of soda-lime or borosilicate substrate glass by means of magnetron sputtering.

[0056] The material of the perovskite absorption layer can be a compound composed of A, B, and X3. Among them, A can be one or more of FA (HC(NH2)2), MA (CH3NH3), Cs, and Rb, B can be one or more of Pb, Sn, and Sr, and X can be one or more of Br, I, and Cl.

[0057] The materials of the electron transport layer include materials such as tin oxide, titanium dioxide, C60, fullerenes, and their derivatives.

[0058] The materials of the electrode include at least one of chromium (Cr) and gold (Au).

[0059] Correspondingly, on the other hand, an embodiment of the present application further provides a method for preparing a perovskite battery, which can be used to manufacture the perovskite battery provided in the above embodiment. The following will detail the method for preparing the perovskite battery provided in another embodiment of the present application. For the same or corresponding parts as those in the previous embodiment, reference can be made to the corresponding description in the previous embodiment, and details will not be repeated below.

[0060] The method for preparing a perovskite battery includes: sequentially forming a hole transport layer, a perovskite absorption layer, an electron transport layer, and an electrode on a transparent conductive substrate.

[0061] The specific steps are as follows:

[0062] S11. Cleaning step: Ultrasonically clean the transparent conductive substrate with deionized water, acetone, and ethanol in sequence for 15 - 20 minutes. After drying the transparent conductive substrate, perform oxygen plasma treatment for 10 - 15 minutes, and then transfer the transparent conductive substrate into a nitrogen glove box;

[0063] S12. Preparing the hole transport layer: Weigh 3 - 15 mg of hole transport material DCz - OME or DCz - SME, dissolve it in 1 mL of chlorobenzene solution. Take an appropriate amount of the mixed solution and drop it onto the transparent conductive substrate. Spin - coat it at a speed of 4000 - 5000 rpm for 20 - 30 s, and then anneal it at 90 - 100 °C for 10 min;

[0064] S13. Preparing the perovskite absorption layer: Cool the transparent conductive substrate with the hole transport layer to room temperature, pre - heat it at 130 - 140 °C for 3 - 5 min. Take 50 μL of perovskite solution and spread it evenly on the surface of the hole transport layer. Spin - coat it at a speed of 3000 - 5000 rpm for 20 - 30 s, and then anneal it at 90 - 100 °C for 10 min. Among them, the solute of the perovskite solution is 3 - bromo - benzylammonium iodide or 3 - chloro - benzylammonium iodide, methylammonium chloride, and lead iodide, and the solvent is N,N - dimethylformamide and dimethyl sulfoxide;

[0065] S14. Preparing the electron transport layer: Cool the transparent conductive substrate with the perovskite absorption layer to room temperature. Take 40 μL of a solution of (6,6) - phenyl - C61 - butyric acid methyl ester with a concentration of 15 mg / mL, spread the (6,6) - phenyl - C61 - butyric acid methyl ester solution on the perovskite absorption layer. Spin - coat it at a speed of 1000 - 2000 rpm for 30 - 50 s, and then anneal it at 70 - 80 °C for 10 min;

[0066] S15. Preparing the electrode: Place the transparent conductive substrate with the electron transport layer in a vacuum evaporation chamber, and evaporate at least one of metal chromium or gold on the electron transport layer.

[0067] The preparation steps of the hole transport material 4PA - POZ or 4PA - PTZ are as follows:

[0068] S21. Add the first compound, the second compound, tetrakis(triphenylphosphine)palladium, and potassium carbonate to a solvent. The solvent is toluene, ethanol, and water, and the volume ratio of toluene, ethanol, and water is 2:1:1. React at 80 °C to 90 °C for 6 h to 12 h. After cooling to room temperature, extract the organic phase with DCM. Dry the organic phase with anhydrous Mg2SO4, filter, and perform vacuum distillation to obtain the third compound. The chemical formula of the first compound is:

[0069] X is independently selected from O or S;

[0070] The chemical formula of the second compound is:

[0071]

[0072] The reaction formula for preparing the third compound is:

[0073]

[0074] In some embodiments, the molar ratio of the first compound, the second compound, tetrakis(triphenylphosphine)palladium, and potassium carbonate is 1:(2.2 - 2.5):(0.03 - 0.1):(5 - 7).

[0075] In some embodiments, after obtaining the third compound, it further includes subjecting the third compound to column chromatography purification. The eluent for column chromatography is petroleum ether and dichloromethane with a volume ratio of 4:1.

[0076] S22. Dissolve the third compound in 1,4 - dioxane at 25 °C, add trimethylbromosilane dropwise, and stir for 10 h to 16 h. After removing the solvent by vacuum distillation, obtain a solid powder. Dissolve the solid powder in methanol at room temperature, and gradually add deionized water dropwise until the mixture becomes opaque. Continue to stir for 10 h to 16 h. Dissolve the filtered and washed crude product in tetrahydrofuran and precipitate it in acetone to obtain the hole - transporting material 4PA - POZ or 4PA - PTZ.

[0077] The reaction formula for preparing the hole - transporting material 4PA - POZ or 4PA - PTZ is as follows:

[0078]

[0079] In some embodiments, the molar ratio of the third compound to trimethylbromosilane is 1:(8 - 15).

[0080] The preparation steps of the first compound include:

[0081] S31. Prepare the first product. Dissolve raw material I, 2-thiopheneboronic acid, tetrakis(triphenylphosphine), and potassium carbonate in a solvent, react at 85°C to 95°C for 8 h to 12 h, cool to room temperature, extract the organic phase with dichloromethane, dry the organic phase with anhydrous Mg2SO4, filter, and obtain the first product after vacuum distillation.

[0082] The chemical formula of raw material I is:

[0083]

[0084] The reaction formula for preparing the first product is:

[0085]

[0086] In some embodiments, the molar ratio of raw material I, 2-thiopheneboronic acid, tetrakis(triphenylphosphine), and potassium carbonate is 1:(1.1 - 1.5):(0.05 - 0.1):(2.5 - 4).

[0087] In some embodiments, after obtaining the first product, it further includes subjecting the first product to column chromatography purification. The eluent for column chromatography is petroleum ether and dichloromethane with a volume ratio of 12:1.

[0088] S32. Dissolve the first product in tetrahydrofuran, stir at -70°C to -80°C for 10 min to 20 min, dropwise add n-butyllithium, react at -70°C to -80°C for 1 h to 2 h, then add bis(pinacolato)diboron, continue to react at -70°C to -80°C for 1 h to 2 h, subsequently react at room temperature for 10 h to 16 h, extract the organic phase with dichloromethane, dry the organic phase with anhydrous Mg2SO4, filter, and obtain the first compound after vacuum distillation.

[0089] The reaction formula for preparing the first compound is:

[0090]

[0091] In some embodiments, the molar ratio of the first product, n-butyllithium, and bis(pinacolato)diboron is 1:(1.1 - 1.3):(1.2 - 1.5).

[0092] In some embodiments, after obtaining the first compound, it further includes subjecting the first compound to column chromatography purification. The eluent for column chromatography is petroleum ether and dichloromethane with a volume ratio of 15:1.

[0093] The preparation steps of the second compound include:

[0094] S41. Prepare the second product. Dissolve raw material II, tetrabutylammonium bromide, and potassium hydroxide in 1,4-dibromobutane for a substitution reaction. React at 65 °C to 70 °C for 12 h to 24 h. After the reaction is completed, quench with water, extract the organic phase with dichloromethane, dry the organic phase with anhydrous Mg2SO4, filter, and distill under reduced pressure to obtain the second product.

[0095] The chemical formula of raw material II is:

[0096] Each X independently selected from O or S.

[0097] The reaction formula for preparing the second product is:

[0098]

[0099] In some embodiments, the molar ratio of raw material II, tetrabutylammonium bromide, potassium hydroxide, and 1,4-dibromobutane is 1:(0.1 - 0.2):(5 - 10):(50 - 150).

[0100] In some embodiments, after obtaining the second product, it further includes subjecting the second product to column chromatography purification. The eluent for column chromatography is petroleum ether and dichloromethane with a volume ratio of 10:1.

[0101] S42. React the second product with triethyl phosphite at 140 °C to 150 °C for 12 h to 16 h, and distill under reduced pressure to obtain the second compound.

[0102] The reaction formula for preparing the second compound is:

[0103]

[0104] In some embodiments, the molar ratio of the second product to triethyl phosphite is 1:(25 - 50).

[0105] The preparation method of the hole transport materials 4PA-POZ or 4PA-PTZ provided by the embodiments of the present application has low raw material cost, simple preparation process, and is suitable for industrial production.

[0106] According to some embodiments of the present application, on the other hand, the present application provides a tandem battery, including: a top cell, which is the perovskite battery in the above embodiments; a crystalline silicon bottom cell, which is located on the side of the transparent conductive substrate of the perovskite battery away from the electrode.

[0107] The crystalline silicon bottom cell includes any one of PERC cells (Passivated Emitter and Rear Cell), PERT cells (Passivated Emitter and Rear Totally-diffused cell), TOPCon cells (Tunnel Oxide Passivated Contact), HIT / HJT cells (Heterojunction Technology), or BC cells (BackContact).

[0108] The crystalline silicon bottom cell also includes monocrystalline silicon solar cells, polycrystalline silicon solar cells, amorphous silicon solar cells, or compound solar cells. The compound solar cells may specifically be cadmium sulfide solar cells, gallium arsenide solar cells, copper indium selenide solar cells, or perovskite solar cells.

[0109] According to some embodiments of the present application, on the other hand, the present application provides a photovoltaic module, including: a plurality of stacked cells as described in the above embodiments; a connecting member for connecting adjacent stacked cells; a glue film covering the surface of the stacked cells; and a cover plate located on the surface of the glue film away from the stacked cells.

[0110] The connecting member includes an interconnecting solder tape and a busbar solder tape. The interconnecting solder tape is a tinned solder tape for connecting the stacked cells, collecting, and transmitting the current of the stacked cells. The busbar solder tape is a tinned solder tape for connecting the stacked cell strings and the junction box and transmitting the current of the stacked cell strings.

[0111] The glue film may be an organic encapsulation glue film such as ethylene-vinyl acetate copolymer (EVA) glue film, polyolefin elastomer (POE) glue film, or polyvinyl butyral (PVB) glue film.

[0112] The cover plate may be a cover plate with a light-transmitting function such as a glass cover plate or a plastic cover plate. In some embodiments, the surface of the cover plate facing the encapsulation layer may be a concave-convex surface to increase the utilization rate of incident light.

[0113] The following are specific embodiments of the present application:

[0114] Example 1

[0115] Prepare 4PA-POZ:

[0116] Prepare the first product. Add 1.15 g of raw material I, 0.45 g of 2-thiopheneboronic acid, 0.092 g of tetrakis(triphenylphosphine), 1.2 g of potassium carbonate, and 40 mL of N,N-dimethylformamide into a 100 mL two-necked flask. React at 85 °C for 8 h. After cooling to room temperature, extract the organic phase with dichloromethane. Dry the organic phase with anhydrous Mg2SO4, filter, and then obtain the first product by distillation under reduced pressure. Purify the first product by column chromatography. The eluent is a mixture of petroleum ether and dichloromethane with a volume ratio of 12:1, and the purified first product is obtained (yield: 71%).

[0117] Prepare the first compound. Add 4.2 g of the first product and 30 mL of tetrahydrofuran into a 500 mL three-necked flask. Stir at -78 °C for 10 min, and then dropwise add 3.75 mL of n-butyllithium (the molar concentration of n-butyllithium in hexane is 1.6 M). React at -78 °C for 1 h, then add 2.75 mL of bis(pinacolato)diboron, and react at -78 °C for 1 h. Then react at room temperature for 12 h. Quench the reaction with 50 mL of deionized water, extract the organic phase with saturated sodium chloride solution and dichloromethane, dry the organic phase with anhydrous Mg2SO4, filter, and then obtain the second product by distillation under reduced pressure. Purify the first compound by column chromatography. The eluent of the column chromatography is a mixture of petroleum ether and dichloromethane with a volume ratio of 15:1, and the purified first compound is obtained (yield: 80%).

[0118] Prepare the second product. Add 0.93 g of raw material II, 0.32 g of tetrabutylammonium bromide, and 15 mL of 1,4-dibromobutane into a 100 mL two-necked flask. Dropwise add 5 mL of a 50% potassium hydroxide aqueous solution. Heat the mixture to 65 °C and stir for 12 h. Quench the reaction with water, extract the organic phase with dichloromethane, dry the organic phase with anhydrous Mg2SO4, filter, and then obtain the second product by distillation under reduced pressure. Purify the second product by column chromatography. The eluent of the column chromatography is a mixture of petroleum ether and dichloromethane with a volume ratio of 10:1, and the purified second product is obtained (yield: 85%).

[0119] Among them, the chemical formula of raw material II is:

[0120]

[0121] Prepare the second compound. Add 1.14 g and 10 mL of triethyl phosphite into a 100 mL two-necked flask. Heat the mixture to 160 °C and react for 12 h. Remove the organic solvent by rotary evaporator to obtain the crude product of the second compound (yield: 92%).

[0122] Prepare the third compound. Add 1.2 g of the first compound, 0.53 g of the second compound, 57 mg of tetrakis(triphenylphosphine)palladium, 0.83 g of potassium carbonate, and a solvent into a 100 mL two-necked flask. The solvent is toluene, ethanol, and water with a volume ratio of 2:1:1. React at 85 °C for 6 h. After cooling to room temperature, extract the organic phase with DCM. Dry the organic phase with anhydrous Mg2SO4, filter, and obtain the third compound after vacuum distillation. Purify the third compound by column chromatography. The eluent for column chromatography is petroleum ether and dichloromethane with a volume ratio of 4:1, and the purified second product (yield 72%) is obtained.

[0123] Prepare 4PA-POZ. Add 2.2 g of the third compound and 10 mL of 1,4-dioxane into a 100 mL two-necked flask. Dropwise add 3.06 g of trimethylbromosilane. After stirring at room temperature for 12 h, remove 1,4-dioxane using a rotary evaporator. Dissolve the obtained solid powder in 10 mL of methanol at room temperature. Dropwise add deionized water until the mixture becomes opaque. Continue stirring for 12 h. Wash the obtained crude product with deionized water. Then dissolve the crude product in 5 mL of tetrahydrofuran and precipitate it in 20 mL of acetone. Filter to obtain 4PA-POZ (yield 70%).

[0124] Use 4PA-POZ as a hole transport material to prepare the corresponding perovskite solar cell 1.

[0125] Example 2

[0126] Prepare 4PA-PTZ:

[0127] Prepare the first product. Add 1.2 g of raw material I, 0.46 g of 2-thiopheneboronic acid, 0.093 g of tetrakis(triphenylphosphine), 1.22 g of potassium carbonate, and 40 mL of N,N-dimethylformamide into a 100 mL two-necked flask. React at 85 °C for 8 h. After cooling to room temperature, extract the organic phase with dichloromethane. Dry the organic phase with anhydrous Mg2SO4, filter, and obtain the first product after vacuum distillation. Purify the first product by column chromatography. The eluent is petroleum ether and dichloromethane with a volume ratio of 12:1, and the purified first product (yield 73%) is obtained.

[0128] Prepare the first compound. Add 4.3 g of the first product and 30 mL of tetrahydrofuran into a 500 mL three-necked flask, stir at -78 °C for 10 min, then dropwise add 3.78 mL of n-butyllithium (the molar concentration of n-butyllithium in hexane is 1.6 M). After reacting at -78 °C for 1 h, add 2.65 mL of bis(pinacolato)diboron, react at -78 °C for 1 h, and then react at room temperature for 12 h. Quench the reaction with 50 mL of deionized water, extract the organic phase with saturated sodium chloride solution and dichloromethane, dry the organic phase with anhydrous Mg2SO4, filter, and obtain the second product after vacuum distillation. Purify the first compound by column chromatography. The eluent for column chromatography is petroleum ether and dichloromethane with a volume ratio of 15:1, and the purified first compound is obtained (yield 76%).

[0129] Prepare the second product. Add 0.95 g of raw material II, 0.35 g of tetrabutylammonium bromide, and 15 mL of 1,4-dibromobutane into a 100 mL two-necked flask, dropwise add 5 mL of a 50% potassium hydroxide aqueous solution by mass, heat the mixture to 65 °C and stir for 12 h. Quench the reaction with water, extract the organic phase with dichloromethane, dry the organic phase with anhydrous Mg2SO4, filter, and obtain the second product after vacuum distillation. Purify the second product by column chromatography. The eluent for column chromatography is petroleum ether and dichloromethane with a volume ratio of 10:1, and the purified second product is obtained (yield 86%).

[0130] Among them, the chemical formula of raw material II is:

[0131]

[0132] Prepare the second compound. Add 1.24 g and 10 mL of triethyl phosphite into a 100 mL two-necked flask, heat the mixture to 160 °C and react for 12 h. Remove the organic solvent by rotary evaporator to obtain the crude product of the second compound (yield 92%).

[0133] Prepare the third compound. Add 1.23 g of the first compound, 0.55 g of the second compound, 57 mg of tetrakis(triphenylphosphine)palladium, 0.84 g of potassium carbonate, and a solvent into a 100 mL two-necked flask. The solvent is toluene, ethanol, and water with a volume ratio of 2:1:1. React at 85 °C for 6 h. After cooling to room temperature, extract the organic phase with DCM, dry the organic phase with anhydrous Mg2SO4, filter, and obtain the third compound after vacuum distillation. Purify the third compound by column chromatography. The eluent for column chromatography is petroleum ether and dichloromethane with a volume ratio of 4:1, and the purified second product is obtained (yield 73%).

[0134] To prepare 4PA-PTZ, 2.23 g of the third compound and 10 mL of 1,4-dioxane were added to a 100 mL two-necked flask. 3.1 g of trimethylsilyl bromide was added dropwise. After stirring at room temperature for 12 h, 1,4-dioxane was removed using a rotary evaporator. The obtained solid powder was dissolved in 10 mL of methanol at room temperature, and deionized water was added dropwise until the mixture became opaque. Stirring was continued for 12 h. The crude product obtained by filtration was washed with deionized water, and then the crude product was dissolved in 5 mL of tetrahydrofuran and precipitated in 20 mL of acetone. After filtration, 4PA-POZ was obtained (yield 72%).

[0135] 4PA-PTZ was used as a hole transporting material to prepare the corresponding perovskite solar cell 2.

[0136] The perovskite solar cell 1 and the perovskite solar cell 2 were tested for their photoelectric conversion efficiency. Under the illumination condition of AM 1.5G, the current density-voltage (J-V) characteristic curves were measured by forward and reverse scans at a speed of 0.02 V s-1. The detailed photovoltaic indexes open circuit voltage (Voc), short circuit current density (Jsc), fill factor (FF), and photoelectric conversion efficiency (PCE) are shown in Table 1.

[0137] The hole mobilities and HOMO energy levels corresponding to the hole transporting material 4PA-POZ prepared in Example 1 and the hole transporting material 4PA-PTZ prepared in Example 2 are shown in Table 2.

[0138] Table 1 Photovoltaic indexes corresponding to Example 1 and Example 2

[0139] Experimental Example PCE / % Voc / V <![CDATA[Jsc / mA·cm -2 > FF / % Example 1 18.82 1.21 19.70 78.7 Example 2 19.46 1.21 19.91 80.5

[0140] Table 2 HOMO energy levels and hole mobilities of 4PA-POZ and 4PA-PTZ

[0141] Example HOMO energy level / eV <![CDATA[Hole mobility / cm 2 ·V -1 ·S -1 <!-- 12 -->]]> 4PA - POZ -5.34 <![CDATA[2.55×10 -4 > 4PA - PTZ -5.36 <![CDATA[3.78×10 -4 >

[0142] As shown in Table 1, the perovskite solar cell 1 and the perovskite solar cell 2 provided in the embodiments of the present application have a high fill factor, open circuit voltage, and short circuit current density, and generally have a high photoelectric conversion efficiency. As shown in Table 2, 4PA-POZ and 4PA-PTZ have a high hole mobility, which is beneficial to the extraction and transport of holes. 4PA-POZ and 4PA-PTZ can match the perovskite and have a relatively deep HOMO energy level.

[0143] Those of ordinary skill in the art can understand that the above-described embodiments are specific examples for implementing the present application. In actual applications, various changes can be made to them in form and details without departing from the spirit and scope of the present application. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present application. Therefore, the protection scope of the present application should be subject to the scope defined by the claims.

Claims

1. A perovskite battery, characterized in that: The perovskite cell comprises a transparent conductive substrate, a hole transport layer, a perovskite absorption layer, an electron transport layer and an electrode, wherein the hole transport layer comprises a hole transport material, and the chemical formula of the hole transport material is as follows: Wherein, X is independently selected from O or S.

2. A method for preparing a perovskite battery, characterized in that: include: A hole transport layer, a perovskite absorption layer, an electron transport layer and an electrode are sequentially formed on a transparent conductive substrate, wherein the step of preparing the hole transport layer comprises: preparing the hole transport material according to claim 1 into a solution and then coating it on the transparent conductive substrate, and the step of preparing the hole transport material is as follows: The first compound, the second compound, tetrakis(triphenylphosphine)palladium and potassium carbonate are added to a solvent, wherein the solvent is toluene, ethanol and water, and the volume ratio of toluene, ethanol and water is 2:1:1, and the reaction is carried out at 80°C to 90°C for 6h to 12h, and after cooling to room temperature, the organic phase is extracted with DCM, and the organic phase is dried with anhydrous Mg2SO4, filtered, and distilled under reduced pressure to obtain a third compound; The chemical formula of the first compound is: X is independently selected from O or S; The chemical formula of the second compound is: The third compound is dissolved in 1,4-dioxane at 25°C, trimethylsilyl bromide is added dropwise and stirred for 10 to 16 hours, and the solid powder obtained by distilling off the solvent under reduced pressure is dissolved in methanol at room temperature, and deionized water is added dropwise until the mixture is opaque, and stirring is continued for 10 to 16 hours. The crude product after filtering and washing is dissolved in tetrahydrofuran and precipitated in acetone to obtain the hole transport material.

3. The method for preparing a perovskite battery according to claim 2, characterized in that: The molar ratio of the first compound, the second compound, tetrakis(triphenylphosphine)palladium and potassium carbonate is 1:(2.2-2.5):(0.03-0.1):(5-7).

4. The method for preparing a perovskite battery according to claim 2, characterized in that: The molar ratio of the third compound to trimethylsilyl bromide is 1:(8-15).

5. The method for preparing a perovskite battery according to claim 2, characterized in that: The preparation steps of the first compound include: To prepare the first product, the raw material I, 2-boric acid thiophene, tetrakis(triphenylphosphine) and potassium carbonate are dissolved in a solvent, reacted at 85° C. to 95° C. for 8 h to 12 h, cooled to room temperature, extracted the organic phase with dichloromethane, dried the organic phase with anhydrous Mg2SO4, filtered, and distilled under reduced pressure to obtain the first product; The chemical formula of the raw material I is: The first product is dissolved in tetrahydrofuran, stirred at -70°C to -80°C for 10 min to 20 min, n-butyl lithium is added dropwise, and the mixture is reacted at -70°C to -80°C for 1 h to 2 h, then biboric acid pinacol ester is added, and the reaction is continued at -70°C to -80°C for 1 h to 2 h, and then the reaction is carried out at room temperature for 10 h to 16 h, the organic phase is extracted with dichloromethane, the organic phase is dried with anhydrous Mg2SO4, filtered, and distilled under reduced pressure to obtain the first compound.

6. The method for preparing a perovskite battery according to claim 5, characterized in that: The molar ratio of the raw materials I, 2-boric acid thiophene, tetrakis(triphenylphosphine) and potassium carbonate is 1:(1.1-1.5):(0.05-0.1):(2.5-4); the molar ratio of the first product, n-butyl lithium and bipyralidone is 1:(1.1-1.3):(1.2-1.5).

7. The method for preparing a perovskite battery according to claim 2, characterized in that: The preparation steps of the second compound include: To prepare the second product, raw material II, tetrabutylammonium bromide and potassium hydroxide are dissolved in 1,4-dibromobutane for substitution reaction, and the reaction is carried out at 65°C to 70°C for 12h to 24h. After the reaction is completed, the reaction is quenched with water, and the organic phase is extracted with dichloromethane. The organic phase is dried with anhydrous Mg2SO4, filtered, and distilled under reduced pressure to obtain the second product; The chemical formula of the raw material II is: X is independently selected from O or S; The second product is reacted with triethyl phosphite at 140° C. to 150° C. for 12 h to 16 h, and the second compound is obtained after reduced pressure distillation.

8. The method for preparing a perovskite battery according to claim 7, characterized in that: The molar ratio of the raw material II, tetrabutylammonium bromide, potassium hydroxide and 1,4-dibromobutane is 1:(0.1-0.2):(5-10):(50-150); the molar ratio of the second product to triethyl phosphite is 1:(25-50).

9. A laminated battery, characterized in that: include: A top cell, wherein the top cell is the perovskite cell according to claim 1; A crystalline silicon bottom cell, wherein the crystalline silicon bottom cell is located on a side of the transparent conductive substrate of the perovskite cell away from the electrode.

10. A photovoltaic module, characterized in that: include: A plurality of stacked batteries as claimed in claim 9; A connecting component, the connecting component is used to connect adjacent stacked batteries; An adhesive film, the adhesive film covers the surface of the laminated battery; A cover plate is located on a surface of the adhesive film away from the laminated battery.

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