Solar cell and method of manufacturing the same, photovoltaic module

Abstract

The application relates to the technical field of photovoltaic cells, in particular to a solar cell, a preparation method thereof and a photovoltaic module. The solar cell comprises a perovskite active layer, the material of the perovskite active layer comprises ABX3, and X ions at least comprise halogen ions; and an ion blocking layer, the ion blocking layer is arranged on at least one side surface of the perovskite active layer along the thickness direction, and the ion blocking layer comprises a metal organic framework material with amino groups. The solar cell provided by the application is provided with the ion blocking layer on at least one side surface of the perovskite active layer, the ion blocking layer comprises a metal organic framework material (namely MOF-NH2 material) with amino functional groups, halogen ions migrated to the surface interface of the perovskite active layer are effectively adsorbed and fixed, the migration of the halogen ions in the perovskite solar cell is inhibited, an effective blocking and insulating effect is formed, the stability of the device is improved, and the photoelectric conversion performance and service life of the solar cell are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of photovoltaic cells, in particular to a solar cell, a preparation method thereof and a photovoltaic module. BACKGROUND

[0002] Perovskite solar cells have attracted extensive attention due to their long carrier diffusion length, high light absorption coefficient, adjustable band gap, compatibility with various preparation methods, and simple preparation method.

[0003] However, halogen ion migration easily occurs in perovskite solar cells, which destroys the structure of the perovskite active layer and further leads to a decrease in the performance of the battery. In addition, halogen ion migration also leads to decomposition of the perovskite device and corrosion of the electrode, affecting the stability and service life of the perovskite solar cell. SUMMARY

[0004] Therefore, it is necessary to provide a solar cell, a preparation method thereof and a photovoltaic module to inhibit halogen ion migration in perovskite solar cells and improve the photoelectric conversion performance, stability and service life of the solar cell.

[0005] In a first aspect, the present application provides a solar cell, which comprises: a perovskite active layer, the material of the perovskite active layer comprising ABX3, and X site ions comprising halogen ions; and an ion blocking layer, the ion blocking layer being arranged on at least one side surface of the perovskite active layer along the thickness direction, and the ion blocking layer comprising a metal organic framework material having an amino group.

[0006] In some embodiments, the ion blocking layer is arranged on both side surfaces of the perovskite active layer along the thickness direction.

[0007] In some embodiments, the specific surface area of the metal organic framework material having an amino group is 500 m 2 / g~2000m 2 / g.

[0008] In some embodiments, the thickness of the ion blocking layer is 1 nm~30 nm.

[0009] In some embodiments, the number of amino functional groups of the organic ligand of the metal organic framework material having an amino group is greater than or equal to 2.

[0010] In some embodiments, the organic ligand of the metal organic framework material having an amino group has the following general structure formula: HOOC-L(NH2)2-COOH, L comprises an aromatic hydrocarbon or a carboxyl-substituted aromatic hydrocarbon. 20 C 20 .

[0011] In some embodiments, the organic ligand of the metal-organic framework material having an amino group comprises at least one of 2,5-diaminoterephthalic acid, 3,3-diamino-4,4-dicarboxybiphenyl, a compound represented by formula (1), a compound represented by formula (2), and 2',5'-diamino-[1,1':4',1'']-terphenyl-3,3'',5,5''-tetracarboxylic acid.

[0012] formula (1); formula (2).

[0013] In some embodiments, the organic ligand of the metal-organic framework material having an amino group comprises a compound represented by formula (3).

[0014]

[0015] formula (3).

[0016] In a second aspect of the present application, a method for preparing a solar cell is provided, the method comprising the following steps: forming an ion blocking layer on at least one side surface of a perovskite active layer in a thickness direction; wherein the material of the perovskite active layer comprises ABX3, the X site ion comprises a halogen ion, and the ion blocking layer comprises a metal-organic framework material having an amino group.

[0017] In a third aspect of the present application, a photovoltaic module is provided, the photovoltaic module comprising the solar cell provided in the first aspect above, or the solar cell prepared by the method for preparing a solar cell provided in the second aspect above.

[0018] Compared with the conventional technology, the solar cell provided in the present application has at least the following beneficial effects: the solar cell provided in the present application is provided with an ion blocking layer on at least one side surface of a perovskite active layer, the ion blocking layer comprises a metal-organic framework material (i.e. MOF-NH2 material) having an amino functional group, the MOF-NH2 material has an adjustable porous structure, can adsorb halogen ions on the basis of ensuring charge transport, at the same time, the uncoordinated amino groups in the MOF-NH2 material have a passivation effect on the surface of the perovskite active layer, and can form a hydrogen bond interaction with the halogen ions, effectively adsorbing and fixing free halogen ions migrated to the surface interface of the perovskite active layer, inhibiting the migration of halogen ions (especially iodine ions) in the perovskite solar cell, forming an effective blocking and insulating effect, thereby improving the stability of the device, and further improving the photoelectric conversion performance and service life of the solar cell. BRIEF DESCRIPTION OF DRAWINGS

[0019] For a better description and illustration of the embodiments or examples provided herein, reference can be made to one or more of the accompanying drawings. Additional details or examples used to describe the drawings should not be considered as limiting the scope of the disclosed application, the presently described embodiments or examples, and any of the best modes of these applications presently understood. Moreover, in all the drawings, like reference numerals refer to like parts throughout the several views.

[0020] Figure 1 A schematic diagram of a structure of a solar cell in an embodiment of the present application.

[0021] Reference numerals: 1, solar cell; 10, substrate; 20, first charge transport layer; 30, ion blocking layer; 31, first ion blocking layer; 32, second ion blocking layer; 40, perovskite active layer; 50, second charge transport layer; 60, buffer layer; 70, transparent conductive oxide layer; 80, metal electrode layer. DETAILED DESCRIPTION

[0022] Reference will now be made in detail to embodiments of the present application, one or more examples of which are described hereinbelow. Each example is provided as an explanation and not as a limitation of the application. Indeed, it will be apparent to one of ordinary skill in the art that numerous modifications and variations of the present application are possible in light of the above teachings. For example, features described or illustrated as part of one embodiment can be used with another embodiment to yield a still further embodiment.

[0023] It is therefore intended that the present application cover all such modifications and variations of this application as come within the scope of the appended claims and their equivalents. Other objects, features, and aspects of the present application are disclosed in or are apparent from the following detailed description of the application. It will be understood by those of ordinary skill in the art that the discussion of any such example is intended to be illustrative only and not limiting of the broader aspects of the application.

[0024] In the present application, the technical features described in an open way include both the closed technical solution consisting of the listed features and the open technical solution containing the listed features.

[0025] In the present application, when referring to a numerical interval, unless otherwise specified, the numerical interval is considered to be continuous and includes the minimum and maximum values of the range and every value between the minimum and maximum values. Further, when the range refers to integers, every integer between the minimum and maximum values of the range is included. In addition, when multiple ranges are provided to describe a feature or a characteristic, the ranges can be combined. In other words, unless otherwise indicated, all ranges disclosed herein are to be understood as including any and all sub-ranges subsumed therein.

[0026] If nothing else is specifically stated, all embodiments and optional embodiments of the present application can be combined with each other to form new technical solutions.

[0027] If nothing else is specifically stated, all technical features and optional technical features of the present application can be combined with each other to form new technical solutions.

[0028] If nothing else is specifically stated, all steps of the present application can be performed in sequence or randomly, and preferably in sequence. For example, the method comprises steps (a) and (b), which means that the method can comprise steps (a) and (b) performed in sequence, or steps (b) and (a) performed in sequence. For example, it is mentioned that the method can further comprise step (c), which means that step (c) can be added to the method in any order, for example, the method can comprise steps (a), (b) and (c), or steps (a), (c) and (b), or steps (c), (a) and (b), etc.

[0029] If nothing else is specifically stated, the "comprise" and "include" mentioned in the present application means open or closed. For example, the "comprise" and "include" can mean that other components not listed can also be included or contained, or only the listed components can be included or contained.

[0030] Herein, "aromatic hydrocarbon" refers to an aromatic hydrocarbon group derived from removing two hydrogen atoms from an aromatic ring compound, which can be a monocyclic aryl group, or a fused ring aryl group, or a polycyclic aryl group, and for the polycyclic ring, at least one is an aromatic ring system. For example, "C6-C20aromatic hydrocarbon" means that the number of carbon atoms in the aromatic ring is 6-20. 20 "Aryl" refers to an aryl group containing 6-20 carbon atoms, which can be C6 aryl, C 10 aryl, C 14 aryl, C 18 aryl or C 20 aryl. Suitable examples include, but are not limited to: benzene, biphenyl, naphthalene, chrysene, pyrene, p-terphenyl and derivatives thereof.

[0031] The first aspect of the present application, as shown in the Figure 1 The first aspect of the present application, as shown in the

[0032] The solar cell 1 provided in the present application is provided with an ion blocking layer 30 on at least one side surface of the perovskite active layer 40 in the thickness direction, and the ion blocking layer 30 comprises a metal organic framework material with amino functional groups (i.e. MOF-NH2 material). The MOF-NH2 material has an adjustable porous structure, can adsorb halogen ions on the basis of ensuring charge transport, at the same time, the uncoordinated amino groups in the MOF-NH2 material have a passivation effect on the surface of the perovskite active layer 40, and can form hydrogen bond interaction with halogen ions, effectively adsorb and fix halogen ions migrated to the surface interface of the perovskite active layer 40, inhibit the migration of halogen ions (especially iodine ions) in the perovskite solar cell 1, form an effective blocking and isolation effect, thereby improving the stability of the device, and further improving the photoelectric conversion performance and service life of the solar cell 1.

[0033] In some embodiments, the ion blocking layer 30 is provided on both side surfaces of the perovskite active layer 40. During the operation of the solar cell 1, halogen ions generally migrate to the upper and lower sides in a disorderly manner. Therefore, by providing the ion blocking layer 30 on both side surfaces of the perovskite active layer 40, the double-layer interface of the perovskite active layer 40 can be protected, and the blocking migration effect can be improved.

[0034] In some embodiments, the specific surface area of the metal organic framework material with amino groups is 500 m 2 / g~2000 m 2 / g. For example, the specific surface area of the metal organic framework material with amino groups can be, but is not limited to, 500 m 2 / g, 600 m 2 / g, 700 m 2 / g, 800 m 2 / g, 900 m 2 / g, 1000 m 2 / g, 1100 m 2 / g, 1200 m 2 / g, 1300 m 2 / g, 1400 m 2 / g, 1500 m 2 / g, 1600 m 2 / g, 1700 m 2 / g, 1800 m 2 / g, 1900 m 2 / g, 2000 m 2 / g. The specific surface area of the MOF-NH2 material can reflect the loading and distribution of the amino functional groups on the side, and then affect the accessibility of the pore and the adsorption efficiency of the halogen ions. Therefore, controlling the specific surface area of the metal organic framework material with amino groups in the above range is helpful to improve the migration blocking effect of the MOF-NH2 material on the halogen ions and improve the interface stability of the device. Further, the specific surface area of the metal organic framework material with amino groups is 500 m 2 / g~1000 m 2 / g.

[0035] In some embodiments, the thickness of the ion blocking layer 30 is 1 nm~30 nm. Illustratively, the thickness of the ion blocking layer 30 can be, but is not limited to, 1 nm, 5 nm, 10 nm, 15 nm, 20 nm, 25 nm, 30 nm. Further, the thickness of the ion blocking layer 30 is 5 nm~10 nm.

[0036] In some embodiments, the number of amino functional groups of the organic ligand of the metal organic framework material with amino groups is greater than or equal to 2. In this way, the MOF-NH2 material has a multi-amino structure, and forms a more stable coordination structure with the halogen ions through multi-point hydrogen bonding, which not only enhances the adsorption strength, but also helps to improve the adsorption capacity and the effect of blocking migration.

[0037] In some embodiments, the organic ligand of the metal organic framework material with amino groups has the following general structure formula: HOOC-L(NH2)2-COOH, L includes C6~C 20 aromatic hydrocarbon or carboxyl-substituted C6~C 20 aromatic hydrocarbon.

[0038] In this way, the above-mentioned organic ligand has at least two carboxyl groups and two side-chain amino groups. The carboxyl groups at the end help to enhance the coordination ability of the organic ligand with the central metal ions, promote the stable construction of the metal organic framework, thereby improving the rigidity and film uniformity of the material and enhancing its interface adhesion capacity. The side-chain amino groups do not directly participate in the coordination of the central metal ions, but form a more stable coordination structure with the halogen ions through multi-point hydrogen bonding, which not only enhances the adsorption strength, but also helps to improve the adsorption capacity and the effect of blocking migration.

[0039] In some embodiments, the organic ligand of the metal organic framework material with amino groups includes at least one of 2,5-diamino terephthalic acid, 3,3-diamino-4,4-dicarboxy biphenyl, a compound shown in formula (1), a compound shown in formula (2), and 2',5'-diamino-[1,1':4',1'']-terphenyl-3,3'',5,5''-tetracarboxylic acid.

[0040] Formula (1); Formula (2).

[0041] In some embodiments, L comprises a C6-C20 aromatic hydrocarbon substituted with a carboxyl group. 20 Thus, in addition to the carboxyl group at the end of the organic ligand that participates in coordination with the central ion, the organic ligand also has a side chain carboxyl group. There is a synergistic effect between the side chain amino group and the side chain carboxyl group, and the side chain carboxyl group and the side chain amino group in the organic ligand can interact through an intermolecular hydrogen bond network. For example, when the N-H bond of the amino group acts as a hydrogen bond donor to form a hydrogen bond with the oxygen atom of the carboxyl group (N-H···O), the polarity of the N-H bond is enhanced due to the redistribution of the electron cloud, thereby causing the hydrogen atom in the N-H bond to have a more significant partial positive charge, so that it can form stronger electrostatic attraction and more stable hydrogen bonds with the halide ion.

[0042] Exemplarily, the organic ligand of the metal-organic framework material with an amino group comprises a compound represented by Formula (3).

[0043]

[0044] Formula (3).

[0045] In some embodiments, the central metal ion of the metal-organic framework material with an amino group is any one of Zr 4+ , Ti 4+ , Cr 3+ , Fe 3+ , or Zn 2+ .

[0046] In some exemplary embodiments, the solar cell 1 comprises, in sequence, a substrate 10, a first charge transport layer 20, a first ion blocking layer 31, a perovskite active layer 40, a second ion blocking layer 32, a second charge transport layer 50, a buffer layer 60, a transparent conductive oxide layer 70, and a metal electrode layer 80.

[0047] In some embodiments, the substrate 10 is a crystalline silicon cell, and the solar cell 1 further comprises a tunnel recombination layer, which is stacked between the crystalline silicon cell and the first charge transport layer 20.

[0048] The crystalline silicon cell is selected from any one of a passivated emitter and rear cell (PERC), a tunnel oxide passivated contact solar cell (TOPCon), a heterojunction cell (HJT), a cross- finger back contact cell (IBC), a heterojunction back contact cell (HBC), and a full back contact cell (TBC). When the crystalline silicon cell is used as the substrate 10, the solar cell 1 is a stacked cell, and the crystalline silicon cell is used as a bottom cell of the stacked cell to absorb long-wavelength sunlight.

[0049] The material of the tunneling recombination layer includes at least one of indium tin oxide (ITO), indium zinc oxide (IZO), tungsten-doped indium oxide (IWO), and indium zirconium oxide (IZrO); the tunneling recombination layer functions to recombine the electrons and holes from the bottom cell and the hole transport layer.

[0050] In some embodiments, the substrate 10 is a conductive glass. Exemplarily, the conductive glass can be FTO conductive glass or ITO conductive glass.

[0051] According to some embodiments of the application, the first charge transport layer 20 can be a hole transport layer, and thus the subsequently formed second charge transport layer 50 is an electron transport layer; according to some embodiments of the application, the first charge transport layer 20 is an electron transport layer, and thus the subsequently formed second charge transport layer 50 is a hole transport layer.

[0052] The material of the hole transport layer includes at least one of [2-(9H-carbazol-9-yl)ethyl]phosphonic acid (2PACz), (2-(3,6-dimethyl-9H-carbazol-9-yl)ethyl)phosphonic acid (Me-2PACz), [2-(3,6-dimethoxy-9H-carbazol-9-yl)ethyl]phosphonic acid (MeO-2PACz), [4-(3,6-dimethyl-9H-carbazol-9-yl)butyl]phosphonic acid (4PACz), [4-(3,6-dimethyl-9H-carbazol-9-yl)butyl]phosphonic acid (Me-4PACz), [4-(3,6-dimethoxy-9H-carbazol-9-yl)butyl]phosphonic acid (MeO-4PACz), 2,2',7,7'-tetrakis[N,N-bis(4-methoxyphenyl)amino]-9,9'-spirobifluorene (spiro-OMeTAD), poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA), poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) (PEDOT:PSS), 2,2',7,7'-tetrakis(di-p-tolylamino)spiro-9,9'-bifluorene (spiro-TTB), and nickel oxide (NiO x The hole transport layer functions to collect holes from the perovskite active layer 40 and to block the transport of electrons.

[0053] The material of the electron transport layer includes at least one of C 60 and a fullerene derivative, specifically [6,6]-phenyl-C61-butyric acid methyl ester and [6,6]-phenyl-C71-butyric acid methyl ester (PCBM); the electron transport layer functions to collect electrons from the perovskite active layer 40 and to block the transport of holes.

[0054] The material of the perovskite active layer 40 includes ABX3, A is a monovalent cation, B is a divalent metal cation, and X is an ion that can include iodine ions; optionally, A includes at least one of cesium ions, methylamine ions, ethylamine ions, formamidine ions, benzylamine ions, and phenethylamine ions; B includes at least one of lead ions, tin ions, and copper ions; and X can also include bromine ions or chlorine ions. The perovskite active layer 40 functions to absorb short-wavelength sunlight and generate photo-generated electron-hole pairs.

[0055] The material of the transparent conductive oxide layer 70 includes at least one of indium tin oxide (ITO), indium zinc oxide (IZO), fluorine-doped tin oxide (FTO), aluminum-doped zinc oxide (AZO), tungsten-doped indium oxide (IWO), and indium zirconium oxide (IZrO), and is prepared by a magnetron sputtering method. The transparent conductive oxide layer 70 functions to collect charges that are transported laterally to the metal electrode layer 80.

[0056] The material of the buffer layer 60 includes at least one of tin oxide (SnO x ) and bathocuproin (BCP). The buffer layer 60 functions to improve the contact between the second charge transport layer 50 and the transparent conductive oxide layer 70 and to avoid damage to the second charge transport layer 50 during preparation of the transparent conductive oxide layer 70.

[0057] The material of the metal electrode layer 80 includes at least one of Ag, Cu, Al, and Au. The metal electrode layer 80 functions to transport charges to an external circuit.

[0058] In a second aspect, the present application provides a method for preparing a solar cell, the method including the step of: forming an ion blocking layer on at least one side surface of a perovskite active layer in a thickness direction.

[0059] In some embodiments, the material of the perovskite active layer includes ABX3, and X includes halogen ions. The ion blocking layer includes a metal-organic framework material having an amino group.

[0060] In some embodiments, the ion blocking layer is formed by depositing a precursor solution containing a metal-organic framework material having an amino group, and the concentration of the precursor solution is 0.1 mg / mL to 5 mg / mL. For example, the concentration of the precursor solution can be, but is not limited to, 0.1 mg / mL, 0.5 mg / mL, 1 mg / mL, 2 mg / mL, 3 mg / mL, 4 mg / mL, or 5 mg / mL.

[0061] In some embodiments, the deposition is at least one of spraying or coating.

[0062] In some embodiments, before forming the ion blocking layer on at least one side surface of the perovskite active layer, the method further comprises the step of: preparing the metal-organic framework material with amino groups. The metal-organic framework material with amino groups can be prepared by a solvothermal method. Specifically, the organic ligand and the metal source can be mixed with a solvent and then placed in a reaction kettle for a coordination reaction to form the metal-organic framework material with amino groups. The specific preparation steps and preparation parameters can be appropriately adjusted according to the types of the selected organic ligand and metal ion and the reaction conditions (temperature, time, solvent, etc.) to obtain the MOF-NH2 material with the target structure and performance for building the ion blocking layer.

[0063] In a third aspect, the present application provides a photovoltaic module, which comprises the solar cell provided in the first aspect or prepared by the method provided in the second aspect.

[0064] The solar cells can be arranged in multiple pieces, and the solar cells can be electrically connected to form multiple cell strings in the form of a whole piece or multiple pieces. The multiple cell strings can be electrically connected in series and / or parallel. The photovoltaic module can further comprise an encapsulation layer and a cover plate. The encapsulation layer is used to cover the surface of the cell string, and the cover plate is used to cover the surface of the encapsulation layer away from the cell string. Specifically, in some embodiments, the multiple cell strings can be electrically connected through a conductive band. The encapsulation layer covers the surface of the solar cell. Exemplarily, the encapsulation layer can be an organic encapsulation adhesive film such as an ethylene-vinyl acetate copolymer adhesive film, a polyethylene octene elastomer adhesive film, or a polyethylene terephthalate adhesive film. The cover plate can be a glass cover plate, a plastic cover plate, or a cover plate with a light-transmitting function.

[0065] Based on the same inventive concept, the embodiments of the present application provide a photovoltaic system comprising the photovoltaic module in any of the above embodiments.

[0066] It can be understood that the photovoltaic system can be applied in a photovoltaic power station, such as a ground power station, a roof power station, a water surface power station, etc., and can also be applied in a device or apparatus that utilizes solar energy for power generation, such as a user solar power source, a solar street lamp, a solar car, a solar building, etc. Of course, it can be understood that the application scenarios of the photovoltaic system are not limited to this, that is, the photovoltaic system can be applied in all fields that need to utilize solar energy for power generation. Taking a photovoltaic power generation system network as an example, the photovoltaic system can comprise a photovoltaic array, a combiner box, and an inverter. The photovoltaic array can be an array combination of multiple photovoltaic modules. For example, multiple photovoltaic modules can form multiple photovoltaic arrays. The photovoltaic array is connected to the combiner box. The combiner box can combine the currents generated by the photovoltaic array. The combined current flows through the inverter to convert into alternating current required by the power grid, and then is connected to the power grid to realize solar power supply.

[0067] The application will be further described below in connection with specific examples and comparative examples.

[0068] Unless otherwise specified, the techniques or conditions in the examples are in accordance with those described in the literature or in accordance with the product manual. Unless otherwise specified, the reagents or instruments used are conventional products that can be obtained commercially.

[0069] Synthesis Example 1: This synthesis example provides a method for synthesizing the compound shown in formula (2).

[0070]

[0071] A single-mouth bottle was added with compound a1 (1 eq), 1,3-dibromo-5,5-dimethylhydantoin (DBH, 2 eq), concentrated sulfuric acid (10 v), and stirred at 90°C overnight, cooled to room temperature, poured into ice water, and suction filtered to obtain a yellow solid 2, which was compound a2; a single-mouth bottle was added with compound a2 (1 eq), phthalimide (2 eq), and ethanol (10 v), and stirred at 80°C overnight, cooled to room temperature, adjusted to neutral pH, poured into water, and suction filtered to obtain a solid, which was the compound shown in formula (2).

[0072] In the formula, compound a1 is 2,7-pyrene dicarboxylic acid (CAS#: 214622-81-8).

[0073] Synthesis Example 2: This synthesis example provides a method for synthesizing the compound shown in formula (1).

[0074]

[0075] A single-mouth bottle was added with compound b1 (1 eq), DBH (2 eq), and concentrated sulfuric acid (10 v), and stirred at 90°C overnight, cooled to room temperature, poured into ice water, and suction filtered to obtain a yellow solid, which was compound b2; a single-mouth bottle was added with compound b2 (1 eq), phthalimide (2 eq), and ethanol (10 v), and stirred at 80°C overnight, cooled to room temperature, adjusted to neutral pH, poured into water, and suction filtered to obtain a solid, which was compound b3; a single-mouth bottle was added with compound b3 (1 eq), Boc anhydride (2.5 eq), and tetrahydrofuran (10 v), and stirred at room temperature overnight, and recrystallized with ethanol to obtain a solid, which was compound b4; a single-mouth bottle was added with compound b4 (1 eq), sodium borohydride (2.5 eq), and dichloromethane (10 v), and stirred at room temperature overnight, and recrystallized with ethanol to obtain a solid, which was compound b5; a single-mouth bottle was added with compound b5 (1 eq) and trifluoroacetic acid (10 v), and stirred at room temperature overnight, and recrystallized with ethanol to obtain a solid, which was the compound shown in formula (1).

[0076] In the formula, compound a2 is 2,7-pyrene dicarboxylic acid (CAS#: 214622-81-8).

[0077] Synthesis Example 3: This synthesis example provides a method for synthesizing a compound represented by Formula (3).

[0078]

[0079] Into a two-necked flask, c1 (1 eq) and bis(pinacolato)diboron (Bpin, 2.5 eq) and [1,1'-bis(diphenylphosphino)ferrocene]dichloropalladium (0.1 eq, Pd(dppf)Cl2) were added, potassium acetate and toluene were added, and the mixture was heated under reflux for 12 hours under a nitrogen atmosphere. TLC showed that the starting material was completely reacted. The mixture was cooled to room temperature, concentrated, and purified by column chromatography to obtain a yellow solid c2.

[0080] Into a two-necked flask, c2 (1 eq) and c3 (2.5 eq) were dissolved in toluene, tris(dibenzylideneacetone)dipalladium (Pd2(dba)3) and tri(o-tolyl)phosphine and potassium carbonate solution (2.5 eq) (1M) were added, and finally tetra-n-butylammonium bromide (TBAB) was added. The mixture was heated under reflux for 12 hours under a nitrogen atmosphere. TLC showed that the starting material was completely reacted. The mixture was cooled to room temperature, filtered, extracted with dichloromethane and water, washed with water, dried, concentrated, and recrystallized from acetone to obtain a white solid c4.

[0081] Into a single-necked flask, c4 (1 eq) was added, iron powder (10 eq) and ammonium chloride (3 eq) were added, water was added, and the mixture was stirred at room temperature for 3 hours. TLC showed that there was no starting material left. The mixture was filtered, extracted with dichloromethane and water, washed with water, dried, concentrated, and recrystallized from acetone to obtain a solid, which was the compound represented by Formula (3).

[0082] wherein, compound c1 is 1,4-dibromo-2,5-dinitrobenzene (CAS#: 18908-08-2); and compound c3 is 5-bromobenzene-1,2,4-tricarboxylic acid (CAS#: 13124-84-0).

[0083] Example 1: This example provides a solar cell and a method for preparing the same.

[0084] (1) Cleaning ITO conductive glass: The ITO conductive glass was sequentially placed in deionized water, anhydrous ethanol and acetone, and ultrasonically cleaned for 15 min, and then dried with N2 for standby.

[0085] (2) Preparation of a hole transport layer: 2PACz was dissolved in isopropyl alcohol to prepare a 2PACz solution with a concentration of 0.5 mg / mL; the 2PACz solution was spin-coated onto the surface of the ITO conductive glass to obtain a hole transport layer with a thickness of 1-5 nm.

[0086] (3) Preparation of UiO-66-NH2 material: 0.3 mmol of ZrCl4 and 0.3 mmol of organic ligand 2-amino terephthalic acid (H2BDC-NH2) were weighed and dissolved in 30 mL of dimethylformamide (DMF); the mixed solution was transferred to a reaction kettle and reacted at 120°C for 24 h; the product was washed with DMF and methanol alternately for 3 times each, and dried in a vacuum drying box at 60°C for 12 h to obtain UiO-66-NH2.

[0087] BET test shows that the specific surface area of UiO-66-NH2 is 580 m 2 / g.

[0088] (4) Preparation of the first ion blocking layer: the UiO-66-NH2 powder was dispersed in isopropanol and ultrasonically treated to form a uniform dispersion liquid with a concentration of 1 mg / mL, and the ion blocking layer was deposited on the surface of the hole transport layer by spraying; after drying, the first ion blocking layer with a thickness of 10 nm was formed.

[0089] (5) Preparation of the perovskite active layer: according to the chemical formula FA 0.9 Cs 0.1 PbI3, FAI, CsI and PbI2 were weighed and dissolved in 1 mL of a mixed solvent of dimethylformamide and dimethyl sulfoxide (volume ratio 4:1) to obtain a mixed solution with a concentration of 1.6M; the mixed solution was spin-coated onto the surface of the first blocking layer to obtain a perovskite light-absorbing layer with a thickness of 800 nm.

[0090] (6) Preparation of the second ion blocking layer: the UiO-66-NH2 powder was dispersed in isopropanol and ultrasonically treated to form a uniform dispersion liquid with a concentration of 1 mg / mL, and the ion blocking layer was deposited on the surface of the perovskite active layer by spraying; after drying, the second ion blocking layer with a thickness of 10 nm was formed.

[0091] (7) Preparation of C 60 electronic transport layer: a C 60 thin film was deposited on the surface of the second ion blocking layer by vacuum thermal evaporation, with a deposition thickness of 15 nm.

[0092] (8) Preparation of SnO x buffer layer: a SnO x buffer layer with a thickness of 10 nm was deposited on the electronic transport layer by atomic layer deposition.

[0093] (9) Preparation of transparent conductive oxide layer: an ITO layer was deposited on the SnO x buffer layer by magnetron sputtering, with a thickness of about 70 nm.

[0094] (10) Preparation of Ag electrode: Ag electrode was deposited on the edge area of the device by thermal evaporation process with a thickness of 110 m to form a solar cell.

[0095] Example 2: The solar cell and the preparation method thereof provided in the example are basically the same as those in Example 1, except that in step (3), the reaction temperature is 130℃, and the time is 20 min, and thus the specific surface area of the UiO-66-NH2 prepared is 850 m 2 / g.

[0096] Example 3: The solar cell and the preparation method thereof provided in the example are basically the same as those in Example 1, except that in step (3), the reaction temperature is 200℃, and the time is 30 min, and thus the specific surface area of the UiO-66-NH2 prepared is 1180 m 2 / g.

[0097] Example 4: The solar cell and the preparation method thereof provided in the example are basically the same as those in Example 1, except that in step (3), the organic ligand is replaced by 2', 5'-diamino-[1, 1': 4', 1''-terphenyl-3, 3'', 5, 5''-tetracarboxylic acid], and thus the specific surface area of the MOF-NH2 material prepared is 1600 m 2 / g.

[0098] Example 5: The solar cell and the preparation method thereof provided in the example are basically the same as those in Example 1, except that in step (3), the organic ligand is replaced by the compound shown in formula (1), and thus the specific surface area of the MOF-NH2 material prepared is 2800 m 2 / g.

[0099]

[0100] Formula (1).

[0101] Example 6: The solar cell and the preparation method thereof provided in the example are basically the same as those in Example 1, except that step (4) is omitted, and step (5) is directly prepared on the hole transport layer. The perovskite active layer, and thus the solar cell prepared has only the second ion blocking layer on the surface of the perovskite active layer close to the electron transport layer.

[0102] Example 7: The solar cell and the preparation method thereof provided in the example are basically the same as those in Example 1, except that in step (3), the organic ligand is replaced by the compound shown in formula (3), and thus the specific surface area of the MOF-COOH-NH2 material prepared is 3500 m 2 / g.

[0103]

[0104] Formula (3).

[0105] Comparative Example 1: This comparative example provides a solar cell and a method for preparing the same.

[0106] (1) Cleaning ITO conductive glass: The ITO conductive glass was sequentially placed in deionized water, anhydrous ethanol and acetone, and ultrasonically cleaned for 15 min, respectively, and then dried with N2 for standby.

[0107] (2) Preparation of a hole transport layer: 2PACz was dissolved in isopropanol to prepare a 2PACz solution with a concentration of 0.5 mg / mL; the 2PACz solution was spin-coated onto the surface of the ITO conductive glass to obtain a hole transport layer with a thickness of 2 nm.

[0108] (3) Preparation of a perovskite active layer: according to the chemical formula of the perovskite precursor FA 0.9 Cs 0.1 PbI3, FAI, CsI and PbI2 were weighed and dissolved in 1 mL of a mixed solvent of dimethylformamide and dimethyl sulfoxide (volume ratio of 4:1) to obtain a mixed solution with a concentration of 1.6 M; the mixed solution was spin-coated onto the surface of the hole transport layer to obtain a perovskite light-absorbing layer with a thickness of 800 nm.

[0109] (4) Preparation of a C 60 electronic transport layer: a C 60 film was deposited on the surface of the perovskite active layer by vacuum thermal evaporation, with a deposition thickness of 12 nm.

[0110] (5) Preparation of a SnO x buffer layer: a SnO x buffer layer with a thickness of 10 m was deposited on the electronic transport layer by atomic layer deposition.

[0111] (6) Preparation of a transparent conductive oxide layer: an ITO layer was deposited on the SnO x buffer layer by magnetron sputtering, with a thickness of about 70 nm.

[0112] (7) Preparation of an Ag electrode: an Ag electrode was deposited on the edge area of the device by thermal evaporation, with a thickness of 110 nm, to form a solar cell.

[0113] Comparative Example 2: This comparative example provides a solar cell and a method for preparing the same.

[0114] (1) Cleaning ITO conductive glass: The ITO conductive glass was sequentially placed in deionized water, anhydrous ethanol and acetone, and ultrasonically cleaned for 15 min, respectively, and then dried with N2 for standby.

[0115] (2) Preparation of hole transport layer: 2PACz is dissolved in isopropanol to prepare a 2PACz solution with a concentration of 0.5 mg / mL; the 2PACz solution is spin-coated onto the surface of ITO conductive glass to obtain a hole transport layer with a thickness of 2 nm.

[0116] (3) Preparation of UiO-66 material: 0.3 mmol of ZrCl4 and 0.3 mmol of organic ligand terephthalic acid (BDC) are dissolved in 30 mL of dimethylformamide (DMF); the mixed solution is transferred to a reaction kettle and reacted at 120°C for 24 h; the product is washed with DMF and methanol alternately for 3 times each, and dried in a vacuum drying box at 60°C for 12 h to obtain UiO-66.

[0117] BET test shows that the specific surface area of UiO-66 is 150 m 2 / g.

[0118] (4) Preparation of the first ion blocking layer: UiO-66 powder is dispersed in isopropanol and ultrasonically treated to form a uniform dispersion liquid with a concentration of 1 mg / mL; the ion blocking layer is deposited on the surface of the hole transport layer by spraying; after drying, the first ion blocking layer with a thickness of 10 nm is formed.

[0119] (5) Preparation of perovskite active layer: according to the chemical formula FA 0.9 Cs 0.1 PbI3, FAI, CsI and PbI2 are weighed and dissolved in 1 mL of a mixed solvent of dimethylformamide and dimethyl sulfoxide (volume ratio of 4:1) to obtain a mixed solution with a concentration of 1.6M; the mixed solution is spin-coated onto the surface of the first blocking layer to obtain a perovskite light-absorbing layer with a thickness of 800 nm.

[0120] (6) Preparation of the second ion blocking layer: UiO-66 powder is dispersed in isopropanol and ultrasonically treated to form a uniform dispersion liquid with a concentration of 1 mg / mL; the ion blocking layer is deposited on the surface of the perovskite active layer by spraying; after drying, the second ion blocking layer with a thickness of 10 nm is formed.

[0121] (7) Preparation of C 60 electronic transport layer: C 60 thin film is deposited on the surface of the second ion blocking layer by vacuum thermal evaporation, with a deposition thickness of 12 nm.

[0122] (8) Preparation of SnO x buffer layer: SnO x buffer layer with a thickness of 10 nm is deposited on the electronic transport layer by atomic layer deposition.

[0123] (9) Preparation of transparent conductive oxide layer: SnOx The ITO layer was deposited on the buffer layer by magnetron sputtering, and the thickness was about 70 nm.

[0124] (10) Preparation of Ag electrode: an Ag electrode was deposited on the edge region of the device by a thermal evaporation process, and the thickness was 110 nm, thereby forming a solar cell.

[0125] Performance test: the solar cells prepared in the above examples and comparative examples were placed in a solar simulator (manufacturer: Wavelabs), and under the irradiation of one solar intensity, a test source table was used to apply a bias voltage (Vp, the bias voltage range was -0.1-1.3 V) to the device and test the output current of the device, thereby obtaining a bias voltage-current density curve.

[0126] Open-circuit voltage (Voc): the terminal voltage of the cell piece when no load is connected, that is, the bias voltage value when the current density is 0 mA·cm -2 in the bias voltage-current density curve.

[0127] Short-circuit current density (Jsc): the output current per unit area of the cell piece when short-circuited, that is, the current density when the bias voltage is 0 V in the bias voltage-current density curve.

[0128] Fill factor (FF): FF = max (Vp x Jsc), wherein Vp is the bias voltage and Jsc is the short-circuit current density.

[0129] Photovoltaic cell efficiency (PCE): PCE = Voc x Jsc x FF.

[0130] The initial test results and the test results after 1000 h of the above performances are shown in Table 1.

[0131] Table 1: photovoltaic performance test results of examples and comparative examples.

[0132] Initial Voc (V) Voc after 1000 h (V) Initial Jsc (mA-cm -2 )]> Jsc (mA-cm-2) after 1000 h -2 ​ Initial FF (%) FF after 1000 h (%) Initial PCE (%) PCE after 1000 h (%) Example 1 1.93 1.91 18.25 18.22 0.82 0.79 28.88 27.49 Example 2 1.94 1.93 18.25 18.23 0.82 0.81 29.03 28.50 Example 3 1.94 1.93 18.25 18.24 0.83 0.81 29.39 28.51 Example 4 1.96 1.95 18.25 18.24 0.83 0.82 29.69 29.17 Example 5 1.97 1.97 18.25 18.24 0.83 0.82 29.84 29.46 Example 6 1.94 1.91 18.25 18.24 0.82 0.79 29.03 27.52 Example 7 1.98 1.97 18.25 18.25 0.83 0.82 29.99 29.51 Comparative Example 1 1.93 1.83 18.25 17.12 0.81 0.66 28.54 20.67 Comparative Example 2 1.94 1.89 18.25 18.13 0.81 0.76 28.68 26.04

[0133] As shown in Table 1, comparative examples 1-7 and comparative examples 1-2, the solar cell provided by the present application effectively suppresses the migration of halogen ions in the perovskite solar cell, and improves the photoelectric conversion performance and long-term stability of the solar cell.

[0134] The difference between Example 1 and Comparative Example 2 is whether the MOF material used for the ion barrier contains an amino functional group. As shown in Table 1, although both schemes can improve the photoelectric conversion performance and long-term stability of the device, the MOF material UiO-66 in Comparative Example 2 only forms a physical barrier through its porous structure, although it can play a certain role in ion blocking, but its open-circuit voltage Voc still shows a significant decay of 0.05V after 1000 hours, indicating that simple physical packaging and adsorption cannot solve the problem of non-radiative recombination caused by interface defects and ion migration. In this application, by introducing an amino functional group into the MOF material, the amino group can effectively passivate the defects on the perovskite surface, and at the same time anchor halide ions through hydrogen bonding. Through the synergistic effect of physical blocking and chemical passivation and anchoring, the long-term stability of the perovskite solar cell is improved. Specifically: the Voc of Example 1 only decays by 0.02V after 1000h, and the stability is much higher than that of Comparative Example 2; the PCE retention rate of Example 1 reaches 95.19% after 1000h, which is much higher than the 90.79% of Comparative Example 2, greatly reducing the decay of photoelectric performance.

[0135] The difference between Example 1 and Example 7 is the type of organic ligand. Although both use MOF-NH2 material, the organic ligand used in Example 7 contains both a side chain carboxyl group and a side chain amino group, which can form hydrogen bonds, affecting the electron cloud distribution of the amino group, thereby improving the electrostatic adsorption and bonding of the amino group to halide ions. The carboxyl group in the organic ligand used in Example 1 only coordinates with the central metal ion and does not have the above-mentioned effect. Therefore, as shown in Table 1, the open-circuit voltage, short-circuit current density, fill factor and photoelectric conversion efficiency of Example 7 are all better than those of Example 1, and the decay rate is slower, proving the synergistic effect of the side chain amino group and the side chain carboxyl group.

[0136] The technical features of the above-described embodiments can be combined in any manner. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described, but as long as the combinations of the technical features do not contradict, they should be considered within the scope of the present disclosure.

[0137] The above-described embodiments only express several implementation manners of the present application, and the description is more specific and detailed, but it should not be construed as limiting the scope of the patent of the present application. It should be noted that for ordinary skilled persons in the art, without departing from the technical concept of the present application, a number of modifications and improvements can be made, which are all within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the appended claims.

Claims

1. A solar cell, characterized by, Comprising: a perovskite active layer, a material of the perovskite active layer comprising ABX3, X site ions comprising halogen ions; and an ion blocking layer provided on at least one side surface of the perovskite active layer in a thickness direction, the ion blocking layer comprising a metal organic framework material having an amino group; the organic ligand of the metal organic framework material having an amino group comprising at least one of the following compounds: 2,5-diamino terephthalic acid, 3,3-diamino-4,4-dicarboxy biphenyl, a compound represented by formula (1), a compound represented by formula (2), 2',5'-diamino-[1,1':4',1'']-terphenyl-3,3'',5,5''-tetracarboxylic acid, a compound represented by formula (3); formula (1); formula (2); formula (3).

2. The solar cell according to claim 1, characterized in that, The ion blocking layer is provided on both side surfaces of the perovskite active layer in a thickness direction.

3. The solar cell of claim 1, wherein The specific surface area of the metal organic framework material having an amino group is 500 m 2 / g~2000 m 2 / g.

4. The solar cell of claim 1, wherein The thickness of the ion blocking layer is 1 nm to 30 nm.

5. A method for producing a solar cell, characterized by, Comprising the following steps: forming an ion blocking layer on at least one side surface of a perovskite active layer in a thickness direction; wherein a material of the perovskite active layer comprises ABX3, X site ions comprising at least halogen ions, and the ion blocking layer comprises a metal organic framework material having an amino group; the organic ligand of the metal organic framework material having an amino group comprising at least one of the following compounds: 2,5-diamino terephthalic acid, 3,3-diamino-4,4-dicarboxy biphenyl, a compound represented by formula (1), a compound represented by formula (2), 2',5'-diamino-[1,1':4',1'']-terphenyl-3,3'',5,5''-tetracarboxylic acid, a compound represented by formula (3); formula (1); formula (2); formula (3).

6. A photovoltaic module, characterized by, A solar cell comprising any one of claims 1 to 4, or a solar cell prepared by the method of claim 5.

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