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

Abstract

The invention provides a perovskite solar cell, a laminated solar cell, a preparation method and a photovoltaic module. The perovskite solar cell comprises a perovskite layer, a first passivation layer and a second passivation layer, the first passivation layer and the second passivation layer are sequentially stacked on the perovskite layer, the material of the first passivation layer comprises diamino cation organic ammonium salt, the material of the second passivation layer comprises monoamino cation organic ammonium salt, and the material of the monoamino cation organic ammonium salt comprises diamino cation organic ammonium salt. And the number of carbon atoms in the diamino cation organic ammonium salt is less than that in the monoamino cation organic ammonium salt. Wherein the interface problem of the perovskite layer can be effectively improved, and the photoelectric conversion efficiency of the perovskite solar cell is also effectively improved.

Description

Technical Field

[0001] The present invention relates to the field of photovoltaic technology, and in particular to a perovskite solar cell, a stacked solar cell, a preparation method and a photovoltaic module. Background Art

[0002] The core component of perovskite solar cells is a semiconductor material layer with a perovskite structure, also known as a perovskite layer. The perovskite layer has the advantages of high carrier mobility and good light absorption performance, which makes perovskite solar cells have relatively excellent photoelectric performance. Perovskite solar cells are considered to be the next generation of photovoltaic technology with broad application prospects.

[0003] There is poor interface contact between the perovskite layer and the carrier transport layer. Specifically, there are problems such as energy level mismatch and energy level pinning effect at the interface between the perovskite layer and the carrier transport layer, which leads to a more serious non-radiative recombination problem at the interface. Moreover, in the actual preparation process, due to the film-forming characteristics of the perovskite material, there are many defects on the surface of the formed perovskite layer, which further aggravates the problem of non-radiative recombination. This has become an important factor restricting the further improvement of device efficiency. Summary of the invention

[0004] Based on this, it is necessary to provide a perovskite solar cell that can improve the interface problem of the perovskite layer in order to improve the photoelectric conversion efficiency of the perovskite solar cell in order to solve the problems in the above-mentioned background technology.

[0005] In a first aspect, according to some embodiments of the present disclosure, a perovskite solar cell is provided, which includes a perovskite layer, a first passivation layer and a second passivation layer, wherein the first passivation layer and the second passivation layer are sequentially stacked on the perovskite layer, the material of the first passivation layer includes a diamino cationic organic ammonium salt, the material of the second passivation layer includes a monoamino cationic organic ammonium salt, and the number of carbon atoms in the diamino cationic organic ammonium salt is less than the number of carbon atoms in the monoamino cationic organic ammonium salt.

[0006] In some embodiments of the present disclosure, the number of carbon atoms on the main carbon chain of the diamino cationic organic ammonium salt is 2 to 4; and / or,

[0007] The molecular size of the diamino cationic organic ammonium salt is 6Å~13Å.

[0008] In some embodiments of the present disclosure, the diamino cationic organic ammonium salt is selected from one or more of ethylenediamine hydrohalide salts, ethylenediamine hydrohalide salt derivatives, propylenediamine hydrohalide salts, propylenediamine hydrohalide salt derivatives, butylene diamine hydrohalide salts and butylene diamine hydrohalide salt derivatives.

[0009] In some embodiments of the present disclosure, the thickness of the first passivation layer is 0.5 nm to 50 nm.

[0010] In some embodiments of the present disclosure, the number of carbon atoms in the monoamino cationic organic ammonium salt is 4 to 20.

[0011] In some embodiments of the present disclosure, the monoamino cationic organic ammonium salt is selected from one or more of butylamine hydrohalide salts, butylamine hydrohalide salt derivatives, phenethylamine hydrohalide salts, phenethylamine hydrohalide salt derivatives, octylamine hydrohalide salts, octylamine hydrohalide salt derivatives, oleylamine hydrohalide salts and oleylamine hydrohalide salt derivatives.

[0012] In some embodiments of the present disclosure, the thickness of the second passivation layer is 0.5 nm to 50 nm.

[0013] In some embodiments of the present disclosure, the perovskite solar cell further includes an electron transport layer and a hole transport layer, the electron transport layer is disposed on a side of the second passivation layer away from the perovskite layer, and the hole transport layer is disposed on a side of the perovskite layer away from the second passivation layer.

[0014] In some embodiments of the present disclosure, the material of the perovskite layer is selected from formamidine-based perovskite materials.

[0015] In some embodiments of the present disclosure, the thickness of the perovskite layer is 500nm~2000nm.

[0016] In a second aspect, the present disclosure further provides a method for preparing a perovskite solar cell as described in any of the above embodiments, comprising the following steps:

[0017] preparing a perovskite layer;

[0018] coating a first passivating agent containing a diamino cationic organic ammonium salt on the perovskite layer to form a first passivation layer; and,

[0019] A second passivator containing a monoamino cationic organic ammonium salt is coated on the perovskite layer to form a second passivation layer, wherein the number of carbon atoms in the diamino cationic organic ammonium salt is less than the number of carbon atoms in the monoamino cationic organic ammonium salt.

[0020] In some embodiments of the present disclosure, the concentration of the monoamino cationic organic ammonium salt in the second passivator is greater than the concentration of the diamino cationic organic ammonium salt in the first passivator.

[0021] In some embodiments of the present disclosure, the concentration of the diamino cationic organic ammonium salt in the first passivator is 0.02 mg / mL to 3 mg / mL; and / or,

[0022] The concentration of the monoamino cationic organic ammonium salt in the second passivating agent is 0.04 mg / mL to 4 mg / mL.

[0023] In some embodiments of the present disclosure, after applying the first passivating agent, a first annealing step is further included; and / or,

[0024] After coating the second passivating agent, the method further includes performing a second annealing treatment.

[0025] In some embodiments of the present disclosure, during the first annealing process, the annealing temperature is controlled to be 20° C. to 150° C., and the annealing time is controlled to be ≤30 min;

[0026] During the second annealing treatment, the annealing temperature is controlled to be 20° C. to 150° C., and the annealing time is controlled to be ≤30 min.

[0027] In a third aspect, the present disclosure further provides a stacked solar cell, which includes a silicon base cell and a perovskite solar cell as described in any of the above embodiments, wherein the perovskite solar cell is stacked on the silicon base cell, and the first passivation layer and the second passivation layer are stacked on a side of the perovskite layer away from the silicon base cell.

[0028] In a fourth aspect, the present disclosure further provides a method for preparing a tandem solar cell as described in any of the above embodiments, comprising the following steps:

[0029] Providing the silicon substrate cell;

[0030] The perovskite solar cell is formed on the silicon substrate cell by using the method for preparing the perovskite solar cell as described in any of the above embodiments.

[0031] Furthermore, the present disclosure also provides a photovoltaic module, which includes a plurality of solar cells, wherein the solar cells are the perovskite solar cells as described in any of the above embodiments, or the solar cells are prepared by the preparation method as described in any of the above embodiments, or the solar cells are the stacked solar cells as described in any of the above embodiments.

[0032] The present disclosure adopts a diamino cation organic ammonium salt with a shorter carbon chain as the material of the first passivation layer, and adopts a monoamino cation organic ammonium salt with a longer carbon chain as the material of the second passivation layer. In the first passivation layer, the two amino cations in the diamino cation organic ammonium salt can be anchored in the perovskite layer at the same time, play a role of chemical passivation, and there is a stronger dipole moment between the two amino cations to form N-type doping, and can also play a role of field passivation at the same time. In the second passivation layer, an amino cation in the monoamino cation organic ammonium salt can also be further anchored in the perovskite layer to make up for the chemical passivation of the first passivation layer. Chemical passivation can reduce the defects on the surface of the perovskite layer, and field passivation can improve the interface energy level matching between the perovskite layer and the carrier transport layer, and reduce non-radiative recombination. On this basis, the carbon chain of the diamino cation organic ammonium salt is shorter, so the two amino cations are closer, and the combination with the perovskite material is more stable and sufficient, thereby achieving a more sufficient passivation effect. The carbon chain of the monoamino cationic organic ammonium salt is relatively long, and it can be laid on the first passivation layer and play the role of isolating water and oxygen and improving the stability of the first passivation layer. Therefore, the short-chain diamino cationic organic ammonium salt is first used, and then the long-chain monoamino cationic organic ammonium salt is used, which can improve the interface defects more fully, obtain better energy level matching, and have better stability, which is more conducive to the transport of carriers. Experiments have shown that the arrangement of the first passivation layer and the second passivation layer has a synergistic effect in improving conversion efficiency. The improvement brought by arranging two passivation layers in the above order is significantly greater than the sum of the improvement brought by the single first passivation layer and the single second passivation layer.

[0033] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention and implement it according to the contents of the specification, the following is a detailed description of the preferred embodiments of the present invention in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present disclosure. For ordinary technicians in this field, drawings of other embodiments can be obtained based on these drawings without creative work.

[0035] Figure 1 A schematic diagram of the structure of a perovskite solar cell;

[0036] Figure 2 A schematic diagram of the structure of a tandem solar cell;

[0037] Figure 3The X-ray diffraction test spectra of the materials of Example 1, Comparative Example 1 and Comparative Example 2;

[0038] Figure 4 This is the current-voltage curve of Example 1.

[0039] The reference numerals and their meanings are as follows:

[0040] 100, perovskite solar cell; 110, perovskite layer; 121, first passivation layer; 122, second passivation layer; 130, electron transport layer; 140, hole transport layer; 150, buffer layer; 160, first transparent conductive layer; 170, anti-reflection layer; 180, first electrode; 200, silicon substrate cell; 210, silicon wafer; 220, first intrinsic silicon layer; 230, first doped silicon layer; 240, second intrinsic silicon layer; 250, second doped silicon layer; 260, second transparent conductive layer; 270, second electrode; 300, composite layer. DETAILED DESCRIPTION

[0041] To facilitate understanding of the present invention, a more comprehensive description of the present invention is provided below. The preferred embodiments of the present invention are given herein. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the content of the present invention more thorough and comprehensive.

[0042] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this document pertains. The terms used herein in the specification of this document are only for describing specific embodiments and are not intended to limit this document.

[0043] It should be understood that when an element or layer is referred to as being "on, "adjacent to, "connected to, or "coupled to" another element or layer, it may be directly on, adjacent to, connected to, or coupled to the other element or layer, or there may be intervening elements or layers. In contrast, when an element is referred to as being "directly on, "directly adjacent to, "directly connected to, or "directly coupled to" another element or layer, there may be no intervening elements or layers. It should be understood that although the terms first, second, third, etc. may be used to describe various elements, components, regions, layers, and / or portions, these elements, components, regions, layers, and / or portions should not be limited by these terms. These terms are merely used to distinguish one element, component, region, layer, or portion from another element, component, region, layer, or portion.

[0044] Spatially relative terms such as "under," "beneath," "below," "under," "above," "above," and the like may be used herein for ease of description to describe the relationship of one element or feature to other elements or features. It should be understood that the spatially relative terms are intended to also include different orientations of the device in use and operation. For example, if the device in the accompanying drawings is flipped, then the elements or features described as "under other elements" or "under" or "under" will be oriented as "over" the other elements or features. Thus, the exemplary terms "under" and "under" may include both upper and lower orientations. The device may be otherwise oriented (e.g., rotated 90 degrees or other orientations) and the spatial descriptors used may be interpreted accordingly.

[0045] The purpose of the terms used herein is only to describe specific embodiments and is not intended to be a limitation of the present disclosure. When used herein, the singular forms "a", "an" and "the" are also intended to include plural forms, unless the context clearly indicates otherwise. It should also be understood that the terms "consisting of" and / or "comprising", when used in this specification, determine the presence of features, integers, steps, operations, elements and / or parts, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, parts and / or groups. When used herein, the term "and / or" includes any and all combinations of the relevant listed items.

[0046] In order to improve the interface non-radiative recombination problem in perovskite solar cells, some traditional technologies propose to use certain passivation materials, such as organic compounds containing specific functional groups, to passivate the surface defects of perovskite materials. However, the passivation effect of this passivation method still needs to be further improved.

[0047] The present disclosure provides a perovskite solar cell, which includes a perovskite layer, a first passivation layer and a second passivation layer, wherein the first passivation layer and the second passivation layer are sequentially stacked on the perovskite layer, the material of the first passivation layer includes a diamino cationic organic ammonium salt, the material of the second passivation layer includes a monoamino cationic organic ammonium salt, and the number of carbon atoms in the diamino cationic organic ammonium salt is less than the number of carbon atoms in the monoamino cationic organic ammonium salt.

[0048] It is understood that the structural formula of the amino cation can be written as "-NH 3 +", is an ion formed by further combining an amino group with a proton. In the perovskite solar cell disclosed in the present invention, a diamino cation organic ammonium salt refers to an organic ionic compound that can be ionized to produce two amino cations, wherein the two amino cations are connected to the same carbon chain. A diamino cation organic ammonium salt can generally be considered to be an organic ionic compound formed by the reaction of an organic compound containing two amino groups with a hydrohalic acid or the like. A monoamino cation organic ammonium salt refers to an organic compound that can be ionized to produce one amino cation, wherein the amino cation is connected to a carbon chain. A monoamino cation organic ammonium salt can generally be considered to be an organic ionic compound formed by the reaction of an organic compound containing one amino group with a hydrohalic acid or the like.

[0049] In the perovskite solar cell disclosed in the present invention, the number of carbon atoms in the diamino cation organic ammonium salt is relatively small, so the carbon chain in the diamino cation organic ammonium salt is relatively short, and the number of carbon atoms in the monoamino cation organic ammonium salt is relatively large, so the carbon chain in the monoamino cation organic ammonium salt is relatively long.

[0050] The present disclosure adopts a diamino cation organic ammonium salt with a shorter carbon chain as the material of the first passivation layer, and adopts a monoamino cation organic ammonium salt with a longer carbon chain as the material of the second passivation layer. In the first passivation layer, the two amino cations in the diamino cation organic ammonium salt can be anchored in the perovskite layer at the same time, play a role of chemical passivation, and there is a stronger dipole moment between the two amino cations to form N-type doping, and can also play a role of field passivation at the same time. In the second passivation layer, an amino cation in the monoamino cation organic ammonium salt can also be further anchored in the perovskite layer to make up for the chemical passivation of the first passivation layer. Chemical passivation can reduce the defects on the surface of the perovskite layer, and field passivation can improve the interface energy level matching between the perovskite layer and the carrier transport layer, and reduce non-radiative recombination. On this basis, the carbon chain of the diamino cation organic ammonium salt is shorter, so the two amino cations are closer, and the combination with the perovskite material is more stable and sufficient, thereby achieving a more sufficient passivation effect. The carbon chain of the monoamino cationic organic ammonium salt is relatively long, and it can be laid on the first passivation layer and play the role of isolating water and oxygen and improving the stability of the first passivation layer. Therefore, the short-chain diamino cationic organic ammonium salt is first used, and then the long-chain monoamino cationic organic ammonium salt is used, which can improve the interface defects more fully, obtain better energy level matching, and have better stability, which is more conducive to the transport of carriers. Experiments have shown that the arrangement of the first passivation layer and the second passivation layer has a synergistic effect in improving conversion efficiency. The improvement brought by arranging two passivation layers in the above order is significantly greater than the sum of the improvement brought by the single first passivation layer and the single second passivation layer.

[0051] Figure 1Schematic diagram of the structure of a perovskite solar cell 100 in the present disclosure. Figure 1 As shown, the perovskite solar cell 100 includes a perovskite layer 110, a first passivation layer 121 and a second passivation layer 122, wherein the first passivation layer 121 and the second passivation layer 122 are sequentially stacked on the perovskite layer 110. The material of the first passivation layer 121 includes a diamino cationic organic ammonium salt, and the material of the second passivation layer 122 includes a monoamino cationic organic ammonium salt, and the number of carbon atoms in the diamino cationic organic ammonium salt is less than the number of carbon atoms in the monoamino cationic organic ammonium salt.

[0052] As some examples of this embodiment, the diamino cationic organic ammonium salt in the first passivation layer 121 directly contacts the perovskite layer 110 , and the monoamino cationic organic ammonium salt in the second passivation layer 122 directly contacts the first passivation layer 121 .

[0053] Furthermore, in this example, the first passivation layer 121 may have pores exposing the perovskite layer 110, the second passivation layer 122 may extend to cover the exposed perovskite layer 110, and the monoamino cationic organic ammonium salt in the second passivation layer 122 may also directly contact the exposed perovskite layer 110, which enables the amino cations in the monoamino cationic organic ammonium salt in the second passivation layer 122 to be anchored in the perovskite layer 110, which can not only further compensate for the chemical passivation effect of the first passivation layer 121, but also improve the structural stability of the first passivation layer 121 and the second passivation layer 122.

[0054] As some examples of this embodiment, the number of carbon atoms on the main carbon chain in the diamino cationic organic ammonium salt is 2 to 4. The distance between adjacent transition metal sites (such as lead sites) in the perovskite layer 110 is about 6.3Å, and the length of the carbon chain formed by 2 to 4 carbon atoms is relatively matched with the above distance, which is conducive to achieving a more comprehensive passivation effect.

[0055] As some examples of this embodiment, the molecular size of the diamino cationic organic ammonium salt can be 6Å~13Å. For example, the molecular size of the diamino cationic organic ammonium salt can be 6Å, 6.3Å, 7Å, 8Å, 9Å, 10Å, 11Å, 12Å, 12.6Å, 13Å, or the molecular size of the diamino cationic organic ammonium salt can also be between any two of the above sizes. More preferably, the molecular size of the diamino cationic organic ammonium salt can be around 6.3Å or around 12.6Å.

[0056] As some examples of this embodiment, the diamino cationic organic ammonium salt may be a hydrohalide salt of a diamine compound. For example, the diamino cationic organic ammonium salt is selected from one or more of ethylenediamine hydrohalide salts, ethylenediamine hydrohalide salt derivatives, propylenediamine hydrohalide salts, propylenediamine hydrohalide salt derivatives, butylene diamine hydrohalide salts and butylene diamine hydrohalide salt derivatives. Among them, ethylenediamine hydrohalide salts, propylenediamine hydrohalide salts and butylene diamine hydrohalide salts have similar properties and sizes, and can achieve good chemical passivation and field passivation effects.

[0057] Further, in this example, the ethylenediamine hydrohalide salt may include but is not limited to ethylenediamine hydroiodide (EDAI 2 ), ethylenediamine hydrochloride (EDACl 2 ) and ethylenediamine hydrobromide (EDABr 2 ) or more. The ethylenediamine hydrohalide derivative may be a product in which one or more hydrogen atoms in the ethylenediamine hydrohalide are further replaced by a functional group, wherein the substituent may be selected from, but not limited to, a halogen atom, "-S-", "-S=", "-S=O", "-N-", "-N=", "-P=" and "-P=O". For example, the ethylenediamine hydrohalide derivative may be fluoroethylenediamine hydroiodide (F-EDAI 2 ). It can be understood that the propylene diamine hydrohalide derivatives and the butyl diamine hydrohalide derivatives can also be understood similarly.

[0058] Further, in this example, the propylene diamine hydrohalide salt may include but is not limited to propylene diamine hydroiodide (PDAI 2 ), propylenediamine hydrochloride (PDACl 2 ) and propylenediamine hydrobromide (PDABr 2 ) or more. The propylene diamine hydrohalide derivative may be fluoropropylene diamine hydroiodide (F-PDAI 2 ).

[0059] Further, in this example, the diamine hydrohalide salt may include but is not limited to diamine hydroiodide (BDAI 2 ), butanediamine hydrochloride (BDACl 2 ) and dibutylamine hydrobromide (BDABr 2 ) or more. The diaminobenzene hydrohalide derivative may be fluorodiaminobenzene hydroiodide (F-BDAI 2 ).

[0060] As some examples of this embodiment, the thickness of the first passivation layer 121 may be 0.5 nm to 50 nm. For example, the thickness of the first passivation layer 121 may be 0.5 nm, 1 nm, 2 nm, 5 nm, 10 nm, 20 nm, 40 nm, or 50 nm. Setting the thickness of the first passivation layer 121 within the above thickness range helps to obtain a better passivation effect while taking into account the transmission of carriers.

[0061] As some examples of this embodiment, the number of carbon atoms in the monoamino cationic ammonium salt is 4 to 20. It is understood that the monoamino cationic ammonium salt can be selected according to the diamino cationic ammonium salt. For example, when the number of carbon atoms in the diamino cationic ammonium salt is 2 or 3, the number of carbon atoms in the monoamino cationic ammonium salt can be 4 or more than 4. When the number of carbon atoms in the diamino cationic ammonium salt is 4, the number of carbon atoms in the monoamino cationic ammonium salt can be more than 4.

[0062] As some examples of this embodiment, the monoamino cationic organic ammonium salt is selected from one or more of butylamine hydrohalide, butylamine hydrohalide derivatives, phenethylamine hydrohalide, phenethylamine hydrohalide derivatives, octylamine hydrohalide, octylamine hydrohalide derivatives, oleylamine hydrohalide and oleylamine hydrohalide derivatives.

[0063] Further, in this example, the butylamine hydrohalide salt may include, but is not limited to, one or more of butylammonium iodide (BAI) and butylammonium chloride (BACl).

[0064] Further, in this example, the phenethylamine hydrohalide salt may include but is not limited to one or more of phenethylammonium iodide (PEAI) and phenethylammonium chloride (PEACl). The phenethylamine hydrohalide salt derivative may include but is not limited to fluorophenethylammonium iodide (F-PEAI), trifluoromethylphenethylammonium chloride (CF 3 -PEACl), one or more of fluorophenethylammonium chloride (F-PEACl) and fluorophenethylammonium bromide (F-PEABr).

[0065] Further, in this example, the octylamine hydrohalide salt may include but is not limited to one or more of octyl ammonium iodide (OAI), octyl ammonium bromide (OABr) and octyl ammonium chloride (OACl). The octylamine hydrohalide salt derivative may include but is not limited to fluorooctyl ammonium iodide (F-OAI).

[0066] Further, in this example, the oleylamine hydrohalide salt may include, but is not limited to, one or more of oleylammonium iodide (OLAI), oleylammonium chloride (OLACl), and oleylammonium bromide (OLABr). The oleylamine hydrohalide salt derivative may include, but is not limited to, fluorooleylammonium iodide (F-OLAI).

[0067] As some examples of this embodiment, the thickness of the second passivation layer 122 may be 0.5 nm to 50 nm. For example, the thickness of the second passivation layer 122 may be 0.5 nm, 1 nm, 2 nm, 5 nm, 10 nm, 20 nm, 40 nm, or 50 nm. Setting the thickness of the first passivation layer 121 within the above thickness range helps to assist in improving the passivation effect and the barrier effect while taking into account the transmission of carriers.

[0068] Reference Figure 1 As shown in some examples of this embodiment, the material of the perovskite layer 110 is selected from a formamidite-based perovskite material. Further, the chemical formula of the formamidite-based perovskite material can be expressed as ABX 3 , wherein A comprises at least the formamidinium cation (FA + ), A may also include cesium ions (Cs + ), methylamine cation (MA + ) and rubidium ions (Rb + ), B can be selected from lead ions (Pb 2+ ) and tin ions (Sn 2+ ), X can be selected from one or more of chloride ion, bromide ion and iodide ion. It is understood that the chemical formula of the formamidinium cation is CH(NH 2 ) 2 + , the chemical formula of the methylamine cation is CH 3 NH 3 + When X is selected from a plurality of halogen anions, the material of the perovskite layer 110 is a mixed halogen perovskite material.

[0069] In this example, the material of the perovskite layer 110 may be FAPbX 3 The raw materials for its preparation may include lead halide (PbX 2 ) and formamidinium halide (FAX). Among them, the lead halide can be PbI 2 The formamidine halide may be one or more of FAI and FABr.

[0070] Reference Figure 1As shown, as some examples of this embodiment, the thickness of the perovskite layer 110 is 500nm~2000nm. As some examples of this embodiment, the thickness of the perovskite layer 110 can be 500nm, 600nm, 800nm, 1000nm, 1200nm, 1500nm, 1700nm, 2000nm, or the thickness of the perovskite layer 110 can also be between any two of the above thicknesses.

[0071] Reference Figure 1 As shown, as some examples of this embodiment, the perovskite solar cell 100 further includes an electron transport layer 130 and a hole transport layer 140, wherein the electron transport layer 130 is disposed on the side of the second passivation layer 122 away from the perovskite layer 110, and the hole transport layer 140 is disposed on the side of the perovskite layer 110 away from the second passivation layer 122. Among them, the hole transport layer 140 is used to extract the holes generated in the perovskite layer 110 and transmit them to the external circuit, and the electron transport layer 130 is used to extract the electrons generated in the perovskite layer 110 and transmit them to the external circuit. In this embodiment, the diamino cationic organic ammonium salt in the first passivation layer 121 has a stronger dipole moment and forms N-type doping, so the first passivation layer 121 is more suitable for improving the interface energy level matching between the perovskite layer 110 and the electron transport layer 130, has a hole blocking effect and can further reduce non-radiative recombination.

[0072] In this example, the material of the electron transport layer 130 may be selected from C 60 , 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP) and tin oxide (SnO x )

[0073] In this example, the thickness of the electron transport layer 130 may be 5 nm to 30 nm. For example, the thickness of the electron transport layer 130 may be 5 nm, 10 nm, 15 nm, 20 nm, 25 nm, or 30 nm, or the thickness of the electron transport layer 130 may be between any two of the above thicknesses.

[0074] In this example, the material of the hole transport layer 140 may be nickel oxide (NiO x ).

[0075] In this example, the thickness of the hole transport layer 140 may be 5 nm to 30 nm. For example, the thickness of the hole transport layer 140 may be 5 nm, 10 nm, 15 nm, 20 nm, 25 nm, or 30 nm, or the thickness of the hole transport layer 140 may be between any two of the above thicknesses.

[0076] Reference Figure 1As shown, as some examples of this embodiment, the perovskite solar cell 100 may further include a first transparent conductive layer 160 and a first electrode 180. The first transparent conductive layer 160 is stacked on a side of the perovskite layer 110 away from the silicon substrate cell 200, and the first electrode 180 is electrically connected to the first transparent conductive layer 160.

[0077] In this example, the material of the first transparent conductive layer 160 may be selected from conductive metal oxides. For example, the material of the first transparent conductive layer 160 may be selected from one or more of indium tin oxide (ITO), indium zinc oxide (IZO), tungsten-doped indium oxide (IWO), aluminum-doped zinc oxide (AZO), and fluorine-doped tin oxide (FTO).

[0078] In this example, the thickness of the first transparent conductive layer 160 may be 30 nm to 150 nm. For example, the thickness of the first transparent conductive layer 160 may be 30 nm, 50 nm, 70 nm, 90 nm, 100 nm, 120 nm, or 150 nm, or the thickness of the first transparent conductive layer 160 may be between any two of the above thicknesses.

[0079] In this example, the material of the first electrode 180 may include a metal material, for example, the material of the first electrode 180 includes one or more of gold, silver, copper, and aluminum.

[0080] In this example, the thickness of the first electrode 180 may be 50 nm to 400 nm. For example, the thickness of the first electrode 180 may be 50 nm, 100 nm, 150 nm, 200 nm, 250 nm, 300 nm, 350 nm, or 400 nm, or the thickness of the first electrode 180 may be between any two of the above thicknesses.

[0081] Reference Figure 1 As shown, as some examples of this embodiment, the perovskite solar cell 100 may further include an anti-reflection layer 170 , and the anti-reflection layer 170 is stacked on a side of the first transparent conductive layer 160 away from the perovskite layer 110 .

[0082] In this example, the thickness of the anti-reflection layer 170 may be 80 nm to 150 nm. For example, the thickness of the anti-reflection layer 170 may be 80 nm, 90 nm, 100 nm, 110 nm, 120 nm, 130 nm, or 150 nm, or the thickness of the anti-reflection layer 170 may be between any two of the above thicknesses.

[0083] Reference Figure 1As shown, as some examples of this embodiment, the perovskite solar cell 100 may further include a buffer layer 150. The buffer layer 150 is stacked on the side of the electron transport layer 130 away from the perovskite layer 110, and the buffer layer 150 is disposed between the electron transport layer 130 and the first transparent conductive layer 160. The buffer layer 150 is used to buffer the interface difference between the electron transport layer 130 and the first transparent conductive layer 160, and improve the quality of the first transparent conductive layer 160.

[0084] In this example, the thickness of the buffer layer 150 may be 5 nm to 30 nm. For example, the thickness of the buffer layer 150 may be 5 nm, 10 nm, 15 nm, 20 nm, 25 nm, or 30 nm, or the thickness of the buffer layer 150 may be between any two of the above thicknesses.

[0085] Reference Figure 1 As shown, as some examples of this embodiment, the perovskite solar cell 100 may further include a counter electrode, which is disposed on a side of the perovskite layer 110 away from the first electrode 180. The counter electrode is used to conduct carriers in the perovskite layer 110, and the polarity of the counter electrode is opposite to that of the first electrode 180.

[0086] The present disclosure also provides a method for preparing Figure 1 The method of the perovskite solar cell 100 shown includes steps S1.1 to S1.3, which are specifically as follows.

[0087] Step S1.1, preparing a perovskite layer 110.

[0088] Combination Figure 1 From the content shown, it can be understood that before preparing the perovskite layer 110, a substrate containing a counter electrode and a hole transport layer 140 can be provided, and the perovskite layer 110 can be prepared on the hole transport layer 140 of the substrate.

[0089] As some examples of this embodiment, the step of preparing the perovskite layer 110 includes: preparing a first precursor material and a second precursor material in sequence, and annealing the first precursor material and the second precursor material to react to form the perovskite layer 110. It can be understood that the first precursor material and the second precursor material should be selected from two raw materials that can combine to affect the perovskite material.

[0090] In this example, the first precursor material may be selected from lead iodide (PbI 2 ) and lead bromide (PbBr 2 )

[0091] In this example, the first precursor material may be prepared by physical vapor deposition, such as evaporation.

[0092] In this example, the second precursor material may be selected from one or more of formamidine iodide (FAI), cesium bromide (CsBr), cesium chloride (CsCl), formamidine bromide (FABr), and methylamine chloride (MACl).

[0093] In this example, the second precursor material may be prepared by a solution method, such as spray coating, spin coating, blade coating, etc.

[0094] Step S1.2, coating a first passivating agent containing the diamino cationic organic ammonium salt on the perovskite layer 110 to form the first passivation layer 121 .

[0095] As some examples of this embodiment, the method of coating the first passivating agent may be selected from spin coating, scraper coating, spray coating, evaporation and the like.

[0096] It can be understood that the first passivator may include a diamino cationic organic ammonium salt and a first solvent, and the diamino cationic organic ammonium salt may be dispersed in the first solvent. The first passivation layer 121 can be formed by removing the first solvent.

[0097] As some examples of this embodiment, the first solvent in the first passivator may be an organic solvent, such as an alcohol organic solvent. In this example, the first solvent may be selected from one or more of ethanol or isopropanol.

[0098] As some examples of this embodiment, the concentration of the diamino cationic organic ammonium salt in the first passivator is 0.02mg / mL~3mg / mL. For example, the concentration of the diamino cationic organic ammonium salt can be 0.02mg / mL, 0.05mg / mL, 0.1mg / mL, 0.2mg / mL, 0.5mg / mL, 0.8mg / mL, 1mg / mL, 1.5mg / mL, 2mg / mL, 3mg / mL, or the concentration of the diamino cationic organic ammonium salt can also be between any two of the above concentrations. The use of the diamino cationic organic ammonium salt of the above concentration is conducive to the presence of a small amount of pores in the formed first passivation layer 121 that expose the perovskite layer 110. The exposed perovskite layer 110 can be used as an anchor point, so that the second passivation layer 122 formed subsequently can have local contact with the perovskite layer 110.

[0099] As some examples of this embodiment, after applying the first passivator, a first annealing step is further included. The first annealing is used to evaporate the first solvent in the first passivator and allow the diamino cationic organic ammonium salt to bond to the surface of the perovskite layer 110, thereby obtaining a better chemical passivation effect and field passivation effect.

[0100] In this example, during the first annealing treatment, the annealing temperature is controlled to be 20°C~150°C. For example, the annealing temperature can be controlled to be 20°C, 40°C, 60°C, 80°C, 100°C, 120°C, 140°C, or 150°C, or the annealing temperature can be between any two of the above temperatures.

[0101] In this example, during the first annealing process, the annealing time is controlled to be ≤30 min. For example, the annealing time can be controlled to be 0.5 min, 1 min, 2 min, 4 min, 8 min, 10 min, 20 min, 30 min, or the annealing time can be controlled to be between any two of the above times.

[0102] Step S1.3, coating a second passivating agent containing the monoamino cationic organic ammonium salt on the perovskite layer 110 to form the second passivation layer 122 .

[0103] It can be understood that the step of forming the second passivation layer 122 is performed after the step of forming the first passivation layer 121, and the second passivation layer 122 covers the surface of the first passivation layer 121 away from the perovskite layer 110. In addition, when there are pores in the first passivation layer 121, the second passivation layer 122 also extends to contact and cover the exposed surface of the perovskite layer 110.

[0104] As some examples of this embodiment, the method of coating the second passivating agent may be selected from spin coating, scraper coating, spray coating, evaporation and the like.

[0105] It can be understood that the second passivating agent may include a monoamino cationic organic ammonium salt and a second solvent, and the monoamino cationic organic ammonium salt may be dispersed in the second solvent. The second passivation layer 122 can be formed by removing the second solvent.

[0106] As some examples of this embodiment, the second solvent in the second passivator may be an organic solvent, such as an alcohol organic solvent. In this example, the second solvent may be selected from one or more of ethanol or isopropanol.

[0107] As some examples of this embodiment, the concentration of the monoamino cationic organic ammonium salt in the second passivator is greater than the concentration of the diamino cationic organic ammonium salt in the first passivator. Among them, the selection of the diamino cationic organic ammonium salt with a lower concentration is helpful to form a relatively loose first passivation layer 121, exposing part of the perovskite layer 110 as an anchor point for the monoamino cationic organic ammonium salt. The selection of the monoamino cationic organic ammonium salt with a higher concentration is helpful to form a more compact second passivation layer 122. This can fully compensate for the chemical passivation effect of the first passivation layer 121 and has a more effective water and oxygen isolation effect.

[0108] As some examples of this embodiment, the concentration of the monoamino cationic organic ammonium salt in the second passivator is 0.04mg / mL~4mg / mL. For example, the concentration of the monoamino cationic organic ammonium salt can be 0.04mg / mL, 0.08mg / mL, 0.2mg / mL, 0.5mg / mL, 1mg / mL, 1.5mg / mL, 2mg / mL, 3mg / mL, 4mg / mL, or the concentration of the monoamino cationic organic ammonium salt can also be between any two of the above concentrations. The use of the monoamino cationic organic ammonium salt of the above concentration is conducive to making the formed second passivation layer 122 more dense and more uniform in thickness.

[0109] As some examples of this embodiment, after coating the second passivating agent, a second annealing step is further included to evaporate the second solvent in the second passivating agent and make the monoamino cationic organic ammonium salt molecules more densely combined.

[0110] In this example, during the second annealing treatment, the annealing temperature is controlled to be 20°C~150°C. For example, the annealing temperature can be controlled to be 20°C, 40°C, 60°C, 80°C, 100°C, 120°C, 140°C, or 150°C, or the annealing temperature can be between any two of the above temperatures.

[0111] In this example, during the second annealing process, the annealing time is controlled to be ≤30 min. For example, the annealing time can be controlled to be 0.5 min, 1 min, 2 min, 4 min, 8 min, 10 min, 20 min, 30 min, or the annealing time can be controlled to be between any two of the above times.

[0112] Combination Figure 1 As shown, after forming the second passivation layer 122 , the step of preparing the electron transport layer 130 , the first transparent conductive layer 160 and the first electrode 180 on the surface of the second passivation layer 122 away from the perovskite layer 110 may also be included.

[0113] Furthermore, after preparing the electron transport layer 130 and before preparing the first transparent conductive layer 160 , a step of preparing the buffer layer 150 may be further included. After preparing the first transparent conductive layer 160 , a step of preparing the anti-reflection layer 170 may be further included.

[0114] It can be understood that after the above steps S1.1 to S1.3, the following Figure 1 The perovskite solar cell 100 is shown.

[0115] Furthermore, the present disclosure also provides a tandem solar cell. Figure 2 Schematic diagram of the structure of the tandem solar cell. Figure 2 As shown, the tandem solar cell includes a silicon substrate cell 200 and a perovskite solar cell 100 in the present disclosure. The perovskite solar cell 100 is stacked on the silicon substrate cell 200, and the first passivation layer 121 and the second passivation layer 122 are stacked and arranged on a side of the perovskite layer 110 away from the silicon substrate cell 200.

[0116] Among them, the perovskite solar cell 100 is arranged on the silicon substrate cell 200 to form a stacked solar cell, which can maintain the advantage of fully capturing sunlight, thereby generating a higher photocurrent.

[0117] Reference Figure 2 As shown in some examples of this embodiment, the tandem solar cell further includes a composite layer 300. The composite layer 300 is disposed between the silicon substrate cell 200 and the perovskite solar cell 100, and is electrically connected to the silicon substrate cell 200 and the perovskite solar cell 100. The composite layer 300 is used to promote the transmission of carriers between the silicon substrate cell 200 and the perovskite solar cell 100.

[0118] In this example, the material of the composite layer 300 may be a transparent conductive material such as a conductive metal oxide, etc. For example, the material of the composite layer 300 may be selected from one or more of indium tin oxide, indium zinc oxide, tungsten-doped indium oxide, aluminum-doped zinc oxide, and fluorine-doped tin oxide.

[0119] In this example, the thickness of the composite layer 300 may be 2 nm to 30 nm. For example, the thickness of the composite layer 300 may be 2 nm, 5 nm, 10 nm, 15 nm, 20 nm, 25 nm, 30 nm, or the thickness of the composite layer 300 may be between any two of the above thicknesses.

[0120] Reference Figure 2 As shown in some examples of this embodiment, the perovskite solar cell 100 includes a hole transport layer 140 and an electron transport layer 130. The arrangement of the hole transport layer 140 and the electron transport layer 130 can refer to Figure 1 The perovskite solar cell 100 is arranged in the manner shown.

[0121] In this example, the hole transport layer 140, the perovskite layer 110 and the electron transport layer 130 are sequentially disposed on a side of the composite layer 300 away from the silicon substrate cell 200. Further, the hole transport layer 140 may directly contact the composite layer 300.

[0122] Reference Figure 2As shown in some examples of this embodiment, the perovskite solar cell 100 includes a first electrode 180 and a first transparent conductive layer 160. The arrangement of the first electrode 180 and the first transparent conductive layer 160 can refer to Figure 1 The perovskite solar cell 100 is arranged in the manner shown.

[0123] Reference Figure 2 As shown, as some examples of this embodiment, the perovskite solar cell 100 may further include a buffer layer 150. The buffer layer 150 is stacked and disposed on a side of the electron transport layer 130 away from the perovskite layer 110.

[0124] Reference Figure 2 As shown, as some examples of this embodiment, the perovskite solar cell 100 may further include an anti-reflection layer 170 , and the anti-reflection layer 170 is stacked on a side of the first transparent conductive layer 160 away from the perovskite layer 110 .

[0125] Further, refer to Figure 2 As shown in some examples of this embodiment, the silicon substrate cell 200 includes a silicon wafer 210, a second electrode 270, and a second transparent conductive layer 260. The second transparent conductive layer 260 is stacked and arranged on a side of the silicon wafer 210 away from the perovskite solar cell 100, and the second electrode 270 is electrically connected to the second transparent conductive layer 260. It can be understood that the first transparent conductive layer 160 and the second transparent conductive layer 260 are used to conduct electrons and holes to the first electrode 180 and the second electrode 270, respectively.

[0126] In this example, the material of the second transparent conductive layer 260 may be selected from conductive metal oxides. For example, the material of the second transparent conductive layer 260 may be selected from one or more of indium tin oxide, indium zinc oxide, tungsten-doped indium oxide, aluminum-doped zinc oxide, and fluorine-doped tin oxide.

[0127] In this example, the thickness of the second transparent conductive layer 260 may be 30 nm to 150 nm. For example, the thickness of the second transparent conductive layer 260 may be 30 nm, 50 nm, 70 nm, 90 nm, 100 nm, 120 nm, or 150 nm, or the thickness of the second transparent conductive layer 260 may be between any two of the above thicknesses.

[0128] In this example, the material of the second electrode 270 may include a metal material, for example, the material of the second electrode 270 includes one or more of gold, silver, copper, and aluminum.

[0129] In this example, the thickness of the second electrode 270 may be 50 nm to 400 nm. For example, the thickness of the second electrode 270 may be 50 nm, 100 nm, 150 nm, 200 nm, 250 nm, 300 nm, 350 nm, or 400 nm, or the thickness of the second electrode 270 may be between any two of the above thicknesses.

[0130] Reference Figure 2 As shown, as some examples of this embodiment, in this tandem solar cell, the silicon base cell 200 may include a silicon wafer 210, a first intrinsic silicon layer 220, a second intrinsic silicon layer 240, a first doped silicon layer 230 and a second doped silicon layer 250. Among them, the doping type of the first doped silicon layer 230 is N-type, and the doping type of the second doped silicon layer 250 is P-type. The first intrinsic silicon layer 220 and the first doped silicon layer 230 are sequentially stacked and arranged on one side surface of the silicon wafer 210, and the second intrinsic silicon layer 240 and the second doped silicon layer 250 are sequentially stacked and arranged on the other side surface of the silicon wafer 210. In this embodiment, the first intrinsic silicon layer 220 and the first doped silicon layer 230 are arranged on the side surface of the silicon wafer 210 close to the perovskite solar cell 100. The second intrinsic silicon layer 240 and the second doped silicon layer 250 are arranged on the side surface of the silicon wafer 210 away from the perovskite solar cell 100.

[0131] The materials of the first intrinsic silicon layer 220 , the first doped silicon layer 230 , the second intrinsic silicon layer 240 , and the second doped silicon layer 250 may be independently selected from amorphous silicon or microcrystalline silicon.

[0132] Reference Figure 2 As shown, in this embodiment, the first intrinsic silicon layer 220 and the first doped silicon layer 230 may be stacked between the silicon wafer 210 and the composite layer 300 .

[0133] The present disclosure also provides a method for preparing Figure 2 The method for producing a stacked solar cell includes steps S2.1 to S2.2, which are specifically as follows.

[0134] Step S2.1, providing a silicon substrate cell 200.

[0135] In this embodiment, the structure of the silicon substrate battery 200 can refer to Figure 2 Specifically, the silicon substrate cell 200 includes a silicon wafer 210, a first intrinsic silicon layer 220, a second intrinsic silicon layer 240, a first doped silicon layer 230, and a second doped silicon layer 250. The first intrinsic silicon layer 220 and the first doped silicon layer 230 are sequentially stacked on one side of the silicon wafer 210, and the second intrinsic silicon layer 240 and the second doped silicon layer 250 are sequentially stacked on the other side of the silicon wafer 210.

[0136] As some examples of this embodiment, the first intrinsic silicon layer 220 and the first doped silicon layer 230 are sequentially stacked on the silicon wafer 210. The silicon substrate battery 200 further includes a second electrode 270 and a second transparent conductive layer 260. The second transparent conductive layer 260 is stacked on a surface of the second doped silicon layer 250 away from the silicon wafer 210, and the second electrode 270 is disposed on a side of the second transparent conductive layer 260 away from the silicon wafer 210.

[0137] As some examples of this embodiment, the doping type of the first doped silicon layer 230 is N-type, and the doping type of the second doped silicon layer 250 is P-type.

[0138] As some examples of this embodiment, the silicon substrate battery 200 can be provided by purchasing it from the market or by preparing it based on the silicon wafer 210. The specific preparation process can be designed accordingly according to the structure, and will not be described in detail here.

[0139] As some examples of this embodiment, the preparation method may further include a step of preparing a composite layer 300 on the silicon substrate cell 200 .

[0140] In this example, the composite layer 300 may be prepared by physical vapor deposition, such as sputtering.

[0141] Step S2.2, forming the perovskite solar cell 100 on the silicon substrate cell 200.

[0142] In this embodiment, the formation of the perovskite solar cell 100 may be performed by referring to the method for preparing the perovskite solar cell 100 shown in steps S1.1 to S1.3.

[0143] As some examples of this embodiment, forming a perovskite solar cell 100 includes the following steps: preparing a hole transport layer 140 on a silicon substrate cell 200, preparing a perovskite layer 110 on the hole transport layer 140, sequentially preparing a first passivation layer 121 and a second passivation layer 122 on the perovskite layer 110, preparing an electron transport layer 130 on the second passivation layer 122, preparing a buffer layer 150 on the electron transport layer 130, preparing a first transparent conductive layer 160 on the buffer layer 150, preparing an anti-reflection layer on the first transparent conductive layer 160, and preparing a first electrode 180 on the anti-reflection layer.

[0144] In this example, the hole transport layer 140 may be prepared by physical vapor deposition, such as sputtering.

[0145] In this example, the method for preparing the perovskite layer 110 can refer to the content shown in step S1.1, the method for preparing the first passivation layer 121 can refer to the content shown in step S1.2, and the method for preparing the second passivation layer 122 can refer to the content shown in step S1.3.

[0146] In this example, the electron transport layer 130 may be prepared by a solution method or a physical vapor deposition method, and the specific preparation method may be selected according to the material of the electron transport layer 130. The physical vapor deposition method may be an evaporation method.

[0147] In this example, the first transparent conductive layer 160 may be prepared by physical vapor deposition, such as sputtering.

[0148] In this example, the anti-reflection layer 170 may be prepared by chemical vapor deposition.

[0149] In this example, the first electrode 180 may be prepared by screen printing a conductive paste and then sintering it.

[0150] After steps S2.1 to S2.2, the following can be formed: Figure 2 The stacked solar cell shown.

[0151] The present disclosure also provides a photovoltaic module, which includes a plurality of solar cells, wherein the solar cells are the perovskite solar cells as described in any of the above embodiments, or the solar cells are prepared by the preparation method as described in any of the above embodiments, or the solar cells are the stacked solar cells as described in any of the above embodiments.

[0152] As an example of this embodiment, the photovoltaic assembly may further include a packaging structure, which may include a first packaging board and a second packaging board that are arranged opposite to each other, and the solar cell is arranged between the first packaging board and the second packaging board.

[0153] Furthermore, the present disclosure also provides the following more specific embodiments and comparative examples and corresponding performance results. The beneficial effects of the present disclosure will also be more easily understood through the following contents.

[0154] The silicon-based battery used in the following embodiments and comparative examples has the same structure. The silicon-based battery is based on an N-type silicon wafer, and both sides of the N-type silicon wafer are sequentially deposited with an intrinsic amorphous silicon layer and a doped amorphous silicon layer, the doped amorphous silicon layer above the N-type silicon wafer is an N-type doped amorphous silicon layer, and the doped amorphous silicon layer below the N-type silicon wafer is a P-type doped amorphous silicon layer. An ITO transparent conductive layer is stacked below the P-type doped amorphous silicon layer, and the bottom of the ITO transparent conductive layer is in contact with the silver electrode.

[0155] Example 1

[0156] A silicon-based battery is provided: an N-type single crystal silicon wafer with a thickness of 150 μm is used as a silicon substrate, a hydrogenated intrinsic amorphous silicon layer with a thickness of 7 nm and a phosphorus-doped amorphous silicon layer with a thickness of 20 nm are sequentially deposited on the front side of the silicon substrate, and a hydrogenated intrinsic amorphous silicon layer with a thickness of 9 nm, a boron-doped amorphous silicon layer with a thickness of 20 nm and a transparent indium tin oxide conductive layer with a thickness of 70 nm are sequentially deposited on the back side of the silicon substrate.

[0157] ITO was sputter-deposited as a composite layer on the silicon-based cell with a thickness of 10 nm.

[0158] Sputtering NiO on the composite layer x As the hole transport layer, the thickness of the hole transport layer was 15 nm.

[0159] Evaporation of PbI on the hole transport layer 2 , then coated with FAI and annealed at 150°C for 15 min to form a perovskite layer with a thickness of 1000 nm.

[0160] The first passivation agent is spin-coated on the perovskite layer. The solvent of the first passivation agent is isopropanol and the solute is propylene diamine hydroiodide (PDAI 2 ), PDAI 2 The concentration of the coating was 0.5 mg / mL. After spin coating, the coating was annealed at 100°C for 5 min to form the first passivation layer.

[0161] The second passivation agent is spin-coated on the perovskite layer, the solvent of the second passivation agent is isopropanol, the solute is butylammonium iodide (BAI), and the concentration of BAI is 1 mg / mL. After spin coating, annealing is performed at 100° C. for 5 minutes to form a second passivation layer.

[0162] Evaporate C on the second passivation layer 60 As the electron transport layer, the thickness of the electron transport layer was 15 nm.

[0163] Sputtering SnO on the electron transport layer x As a buffer layer, the buffer layer thickness is 15 nm.

[0164] ITO material is sputtered on the buffer layer as a transparent conductive layer, and MgF x As an anti-reflection layer. Conductive silver paste is screen-printed on the transparent conductive layer as an electrode.

[0165] Example 2

[0166] Example 2 is basically the same as Example 1, except that Example 2 uses fluoroethylenediamine hydroiodide (F-EDAI 2 ) as the solute of the first passivating agent.

[0167] Example 3

[0168] Example 3 is substantially the same as Example 1, with the main difference being that Example 3 uses phenethylammonium iodide (PEAI) as the solute of the second passivating agent.

[0169] Example 4

[0170] Example 4 is substantially the same as Example 1, with the main difference being that Example 4 uses oil-based ammonium iodide (OLAI) as the solute of the second passivating agent.

[0171] Example 5

[0172] Example 5 is substantially the same as Example 1, with the main difference being that Example 5 uses fluorooctyl ammonium iodide (F-OAI) as the solute of the second passivating agent.

[0173] Example 6

[0174] Example 6 is basically the same as Example 1, except that: Example 6 uses dibutyl diamine hydroiodide (BDAI 2 ) is used as the solute of the first passivating agent, and oily ammonium iodide (OLAI) is used as the solute of the second passivating agent.

[0175] Comparative Example 1

[0176] Comparative Example 1 is substantially the same as Example 1, with the main difference being that in Comparative Example 1, neither the first passivation layer nor the second passivation layer is formed.

[0177] Comparative Example 2

[0178] Comparative Example 2 is substantially the same as Example 1, with the main difference being that in Comparative Example 2, only the first passivation layer is formed, and the second passivation layer is not formed.

[0179] Comparative Example 3

[0180] Comparative Example 3 is substantially the same as Example 1, with the main difference being that in Comparative Example 3, only the second passivation layer is formed, and the first passivation layer is not formed.

[0181] Comparative Example 4

[0182] Comparative Example 4 is basically the same as Example 1, except that: Comparative Example 4 uses dibutyl diamine hydroiodide (BDAI 2 ) is used as the solute of the first passivating agent, and ethylammonium iodide (EAI) is used as the solute of the second passivating agent.

[0183] Comparative Example 5

[0184] Comparative Example 5 is basically the same as Example 1, except that: Comparative Example 5 uses dibutyl diamine hydroiodide (BDAI 2) is used as the solute of the first passivating agent, and butylammonium iodide (BAI) is used as the solute of the second passivating agent.

[0185] Comparative Example 6

[0186] Comparative Example 6 is substantially the same as Example 1, with the main difference being that in Comparative Example 6, the second passivating agent is first used to form the second passivation layer, and then the first passivating agent is used to form the first passivation layer.

[0187] Experiment 1: X-ray diffraction tests were performed on the materials of Example 1, Comparative Example 1 and Comparative Example 2, and the test spectra are shown in Figure 3 .

[0188] Reference Figure 3 As shown, Example 1, Comparative Example 1 and Comparative Example 2 all have diffraction peaks near 12.7°, and the diffraction peaks correspond to the crystal structure of the perovskite layer. Among them, Comparative Example 1 does not prepare the first passivation layer and the second passivation layer, and its diffraction peak is sharper and has a higher intensity. This is mainly because the surface of the perovskite layer in Comparative Example 1 is not passivated, so more perovskite lattices can be detected. Comparative Example 2 only prepares the first passivation layer, and its diffraction peak is lower than that of Comparative Example 1, indicating that the perovskite layer of Comparative Example 2 has been passivated to a certain extent. The diffraction peak intensity of Example 1 is lower, indicating that the perovskite layer of Example 1 has been more effectively passivated on the basis of Comparative Example 2.

[0189] Test 2: Testing the open circuit voltage V of the above embodiments and comparative examples OC , short circuit current J SC , fill factor FF and conversion efficiency PCE, the results can be seen in Table 1. Among them, the current-voltage curve of Example 1 is shown in Figure 4 .

[0190] Table 1

[0191]

[0192] As shown in Table 1, after preparing the perovskite layer, Example 1 also forms a first passivation layer and a second passivation layer, and its filling factor reaches 81.64% and the conversion efficiency reaches 32.23%. In contrast, Comparative Example 1 does not prepare the first passivation layer and the second passivation layer, and its conversion efficiency is only 30.23%. This shows that the structural design of the first passivation layer and the second passivation layer can effectively improve the conversion efficiency of the solar cell. Further, Comparative Example 2 only prepares the first passivation layer, and its conversion efficiency is increased by 1.13% compared with Comparative Example 1, and Comparative Example 3 only prepares the second passivation layer, and its conversion efficiency is increased by 0.50% compared with Comparative Example 1. The conversion efficiency of Example 1 is increased by 2% compared with Comparative Example 1, and the increase is significantly higher than the sum of the increases of Comparative Examples 2 and Comparative Examples 3, indicating that the simultaneous provision of the first passivation layer and the second passivation layer has the effect of promoting each other and synergizing.

[0193] In Examples 2 to 6, other types of monoamino cationic organic ammonium salts are used as the first passivating agent and / or other types of diamino cationic organic ammonium salts are used as the second passivating agent, respectively, and their conversion efficiency is also significantly higher than that of Comparative Examples 1 to 3, indicating that other monoamino cationic organic ammonium salts and diamino cationic organic ammonium salts can also play a similar passivation effect. The conversion efficiency performance of Examples 2 to 6 is slightly lower than that of Example 1, which is mainly because the passivation effect of other types of organic ammonium salts used in Examples 2 to 6 is relatively poor.

[0194] In addition, Comparative Example 4 uses a monoamino organic cation organic ammonium salt with a shorter carbon chain as the second passivator, and Comparative Example 5 uses a monoamino organic cation organic ammonium salt with an equal number of carbon atoms as the second passivator, and their conversion efficiencies are lower than those of Comparative Example 2, which shows that when the carbon chain of the organic ammonium salt located in the upper layer is shorter or the same, it not only cannot make up for the chemical passivation effect of the first passivation layer, but also acts as an impurity material and has a negative impact on the conversion efficiency of the battery. Comparative Example 6 reverses the formation order of the first passivation layer and the second passivation layer, and its conversion efficiency is similar to that of Comparative Example 3, indicating that the second passivation layer located at the bottom of the solar cell only exerts its original passivation effect, and the first passivation layer located at the top basically has no passivation effect.

[0195] Please note that the above embodiments are for illustrative purposes only and are not meant to be limiting of this document.

[0196] It should be understood that, unless otherwise specified herein, there is no strict order restriction for the execution of the steps, and the steps may be executed in other orders. Moreover, at least a portion of the steps in the preparation process may include multiple sub-steps or multiple stages, and these sub-steps or stages are not necessarily executed at the same time, but may be executed at different times, and the execution order of these sub-steps or stages is not necessarily sequential, but may be executed in turn or alternately with other steps or at least a portion of the sub-steps or stages of other steps.

[0197] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0198] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

Claims

1. A perovskite solar cell, characterized in that: The invention comprises a perovskite layer, a first passivation layer and a second passivation layer, wherein the first passivation layer and the second passivation layer are sequentially stacked on the perovskite layer, the material of the first passivation layer comprises a diamino cationic organic ammonium salt, the material of the second passivation layer comprises a monoamino cationic organic ammonium salt, and the number of carbon atoms in the diamino cationic organic ammonium salt is less than the number of carbon atoms in the monoamino cationic organic ammonium salt.

2. The perovskite solar cell according to claim 1, characterized in that: The number of carbon atoms on the main carbon chain of the diamino cationic organic ammonium salt is 2 to 4; and / or, The molecular size of the diamino cationic organic ammonium salt is 6Å~13Å.

3. The perovskite solar cell according to claim 2, characterized in that: The diamino cationic organic ammonium salt is selected from one or more of ethylenediamine hydrohalide salts, ethylenediamine hydrohalide salt derivatives, propylenediamine hydrohalide salts, propylenediamine hydrohalide salt derivatives, butylenediamine hydrohalide salts and butylenediamine hydrohalide salt derivatives.

4. The perovskite solar cell according to claim 1, characterized in that: The thickness of the first passivation layer is 0.5 nm to 50 nm.

5. The perovskite solar cell according to any one of claims 1 to 4, characterized in that: The number of carbon atoms in the monoamino cationic organic ammonium salt is 4 to 20.

6. The perovskite solar cell according to claim 5, characterized in that: The monoamino cationic organic ammonium salt is selected from one or more of butylamine hydrohalide, butylamine hydrohalide derivatives, phenethylamine hydrohalide, phenethylamine hydrohalide derivatives, octylamine hydrohalide, octylamine hydrohalide derivatives, oleylamine hydrohalide and oleylamine hydrohalide derivatives.

7. The perovskite solar cell according to any one of claims 1 to 4 and 6, characterized in that: The thickness of the second passivation layer is 0.5 nm to 50 nm.

8. The perovskite solar cell according to any one of claims 1 to 4 and 6, characterized in that: The perovskite solar cell further includes an electron transport layer and a hole transport layer. The electron transport layer is arranged on a side of the second passivation layer away from the perovskite layer, and the hole transport layer is arranged on a side of the perovskite layer away from the second passivation layer.

9. The perovskite solar cell according to any one of claims 1 to 4 and 6, characterized in that: The material of the perovskite layer is selected from formamidine-based perovskite materials.

10. The perovskite solar cell according to any one of claims 1 to 4 and 6, characterized in that: The thickness of the perovskite layer is 500nm~2000nm.

11. A method for preparing a perovskite solar cell, characterized in that: The steps include: preparing a perovskite layer; coating a first passivating agent containing a diamino cationic organic ammonium salt on the perovskite layer to form a first passivation layer; and, A second passivator containing a monoamino cationic organic ammonium salt is coated on the perovskite layer to form a second passivation layer, wherein the number of carbon atoms in the diamino cationic organic ammonium salt is less than the number of carbon atoms in the monoamino cationic organic ammonium salt.

12. The method for preparing a perovskite solar cell according to claim 11, characterized in that: The concentration of the monoamino cationic organic ammonium salt in the second passivator is greater than the concentration of the diamino cationic organic ammonium salt in the first passivator.

13. The method for preparing a perovskite solar cell according to claim 12, characterized in that: The concentration of the diamino cationic organic ammonium salt in the first passivator is 0.02 mg / mL to 3 mg / mL; and / or, The concentration of the monoamino cationic organic ammonium salt in the second passivating agent is 0.04 mg / mL to 4 mg / mL.

14. The method for preparing a perovskite solar cell according to any one of claims 11 to 13, characterized in that: After coating the first passivating agent, the method further comprises performing a first annealing step; and / or, After coating the second passivating agent, the method further includes performing a second annealing step.

15. The method for preparing a perovskite solar cell according to claim 14, characterized in that: During the first annealing treatment, the annealing temperature is controlled to be 20°C to 150°C, and the annealing time is controlled to be ≤30min; During the second annealing treatment, the annealing temperature is controlled to be 20° C. to 150° C., and the annealing time is controlled to be ≤30 min.

16. A tandem solar cell, characterized in that: It comprises a silicon-based cell and a perovskite solar cell as claimed in any one of claims 1 to 10, wherein the perovskite solar cell is stacked on the silicon-based cell, and the first passivation layer and the second passivation layer are stacked on a side of the perovskite layer away from the silicon-based cell.

17. The method for preparing a tandem solar cell according to claim 16, characterized in that: The steps include: Providing the silicon substrate cell; The perovskite solar cell is formed on the silicon substrate cell by using the method for preparing the perovskite solar cell according to any one of claims 11 to 15.

18. A photovoltaic module, characterized in that: The invention comprises a plurality of solar cells, wherein the solar cells are the perovskite solar cells as described in any one of claims 1 to 10, or the solar cells are prepared by the preparation method as described in any one of claims 11 to 15, or the solar cells are the stacked solar cells as described in claim 16.

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