Perovskite solar cell, preparation method thereof and power utilization device

Abstract

The invention provides a perovskite solar cell, a preparation method thereof and a power utilization device. The perovskite solar cell comprises a perovskite layer and a passivation layer, ethylenediamine tetraacetic acid and / or ethylenediamine tetraacetic acid salt are / is dispersed in the perovskite layer, the passivation layer is located on the surface of at least one side of the perovskite layer, and the passivation layer comprises at least one of phthalocyanine, porphyrin, crown ether, phthalocyanine derivatives, porphyrin derivatives and crown ether derivatives. In the perovskite solar cell, the ethylenediamine tetraacetic acid salt can passivate the internal crystal boundary of the bulk phase of the perovskite layer, and the passivation layer can passivate the surface defects of the perovskite layer, stabilize the perovskite lattice structure on the surface of the perovskite layer and inhibit water from entering the perovskite layer, so that the improved photoelectric property and stability can be obtained at the same time.

Description

Technical Field

[0001] The present application relates to the technical field of solar cells, and in particular to perovskite solar cells, preparation methods thereof, and electrical devices thereof. Background Art

[0002] Perovskite solar cells have attracted extensive attention due to their excellent optoelectronic properties, such as adjustable band gap, high light absorption coefficient, long carrier lifetime and diffusion length, high defect tolerance, and low-cost low-temperature liquid phase preparation method. In just over a decade, the efficiency of perovskite solar cells has increased from 3.8% to more than 25%, showing great potential. Improving the optoelectronic performance and stability of perovskite solar cells is the key to achieving the commercialization of perovskite solar cells. Summary of the invention

[0003] In view of the technical problems existing in the background technology, the present application provides a perovskite solar cell, aiming to improve the photoelectric performance and stability of the perovskite solar cell.

[0004] The first aspect of the present application provides a perovskite solar cell, comprising: a perovskite layer, in which ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetate are dispersed; a passivation layer, which is located on at least one side surface of the perovskite layer, and the passivation layer includes at least one of phthalocyanine, porphyrin, crown ether, phthalocyanine derivatives, porphyrin derivatives, and crown ether derivatives.

[0005] The perovskite solar cell of the first aspect of the present application has the following beneficial effects: the ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt in the perovskite layer can passivate the internal grain boundaries of the bulk phase of the perovskite layer and reduce the defect state density in the bulk phase of the perovskite layer; the phthalocyanine, porphyrin, crown ether, phthalocyanine derivatives, porphyrin derivatives or crown ether derivatives in the passivation layer can not only passivate the surface defects of the perovskite layer and reduce the defect state density on the surface of the perovskite layer, but also combine with the metal cations on the surface of the perovskite layer through chelation to stabilize the perovskite lattice structure on the surface of the perovskite layer, and at the same time make the passivation layer hydrophobic, which can inhibit water from entering the perovskite layer, so that the perovskite solar cell has both good photoelectric performance and stability.

[0006] In some embodiments of the present application, the ratio of the total molar amount of ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt in the perovskite layer to the molar amount of perovskite in the perovskite layer is less than or equal to 1.2%. This configuration is beneficial for passivating the grain boundary defects in the bulk phase of the perovskite layer while reducing the probability of a significant increase in the series resistance of the perovskite solar cell, thereby improving the photoelectric performance of the perovskite solar cell.

[0007] In some embodiments of the present application, the thickness of the passivation layer is 10 nm to 80 nm. Thus, while the surface defects of the perovskite layer are passivated, water can be inhibited from entering the perovskite layer, and the probability of a significant increase in the series resistance of the perovskite solar cell can be reduced, and water can be inhibited from entering the perovskite layer.

[0008] In some embodiments of the present application, the perovskite solar cell further comprises a substrate, the perovskite layer is located on one side of the substrate, and the passivation layer is provided on the surface of the perovskite layer facing away from the substrate. This configuration is conducive to further passivating the surface defects of the perovskite layer and improving the photoelectric performance and stability of the perovskite solar cell.

[0009] In some embodiments of the present application, the perovskite solar cell further comprises a metal electrode layer, and the passivation layer is provided on the surface of the perovskite layer close to the metal electrode layer. This arrangement is advantageous in inhibiting the migration of metal ions that may be generated by corrosion of the metal electrode layer into the perovskite layer, delaying the degradation of the perovskite layer, and improving the stability of the perovskite solar cell.

[0010] In some embodiments of the present application, ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt are dispersed in the passivation layer, and the ratio of the total molar amount of ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt in the perovskite layer and the passivation layer to the molar amount of perovskite in the perovskite layer is less than or equal to 2%. This configuration is not only conducive to passivating the grain boundary defects in the bulk phase of the perovskite layer while further passivating its surface defects, but also reduces the probability of a significant increase in the series resistance of the perovskite solar cell, thereby further improving the photoelectric performance and stability of the perovskite solar cell.

[0011] In some embodiments of the present application, the number of oxygen in the ring-forming elements of the crown ether and the crown ether derivative is independently 4 to 10. The crown ether and crown ether derivative that meet the given conditions have good hydrophobicity, which is conducive to further inhibiting water from entering the perovskite layer.

[0012] In some embodiments of the present application, the crown ether derivatives include R1, R2, R3, R4, R5, and R6 independently include any one of hydrogen, halogen, alkyl, phenyl, naphthyl, alkoxy, phenoxy, amino, hydroxyl, carboxyl, sulfonic acid, pyridyl, and thienyl. Crown ether derivatives that meet the given conditions have good hydrophobicity, which is beneficial to further inhibit water from entering the perovskite layer.

[0013] In some embodiments of the present application, the porphyrin derivatives include M1 is a metal element, R7 includes any one of hydrogen, halogen, alkyl, phenyl, naphthyl, alkoxy, phenoxy, amino, hydroxyl, carboxyl, sulfonic acid, pyridyl, and thienyl, R8, R9, R 10 , R 11 Each independently includes any one of hydrogen, halogen, alkyl, alkenyl, alkyl, and alkoxy. The porphyrin derivatives satisfying the given conditions have good hydrophobicity and conductivity, which is beneficial to further inhibit water from entering the perovskite layer.

[0014] In some embodiments of the present application, the phthalocyanine derivatives include M2 is a metal element, R 12 , R 13 , R 14 , R 15 Each independently includes any one of hydrogen, halogen, alkyl, phenyl, naphthyl, alkoxy, phenoxy, amino, hydroxyl, carboxyl, sulfonic acid, and pyridyl. The phthalocyanine derivatives satisfying the given conditions have good hydrophobicity and conductivity, which is beneficial to further inhibit water from entering the perovskite layer.

[0015] In some embodiments of the present application, M1 and M2 each independently include at least one of Na, Cu, Fe, Co, Ni, Ca, and Mg.

[0016] In some embodiments of the present application, the ethylenediaminetetraacetate salt includes at least one of sodium ethylenediaminetetraacetate, copper ethylenediaminetetraacetate, iron ethylenediaminetetraacetate, calcium ethylenediaminetetraacetate, magnesium ethylenediaminetetraacetate, cobalt ethylenediaminetetraacetate, and nickel ethylenediaminetetraacetate. Introducing the given range of ethylenediaminetetraacetate salt into the perovskite layer can passivate the grain boundary defects of the perovskite.

[0017] The second aspect of the present application provides a method for preparing the perovskite solar cell of the first aspect of the present application, comprising: forming a perovskite layer, dispersing ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt in the perovskite layer; forming a passivation layer, so that the passivation layer is located on at least one side of the perovskite layer, and the passivation layer includes at least one of phthalocyanine, porphyrin, crown ether, phthalocyanine derivatives, porphyrin derivatives, and crown ether derivatives. The method for preparing a perovskite solar cell of the second aspect of the present application is conducive to improving the photoelectric performance and stability of the perovskite solar cell.

[0018] In some embodiments of the present application, the perovskite layer is formed using a perovskite solution, and the passivation layer is formed using a passivation solution, and at least one of the perovskite solution and the passivation solution contains ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetate.

[0019] In some embodiments of the present application, in the passivation solution, the sum of the concentrations of the phthalocyanine, the porphyrin, the crown ether, the phthalocyanine derivative, the porphyrin derivative, and the crown ether derivative is 0.1 mg / mL-8 mg / mL. Controlling the passivation solution to meet the given conditions is conducive to regulating the thickness of the passivation layer and further improving the photoelectric performance and stability of the perovskite solar cell.

[0020] In some embodiments of the present application, the ratio of the total molar concentration of ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt in the perovskite solution to the molar concentration of perovskite in the perovskite solution is 0.02%-1.2%. Controlling the perovskite solution to meet the given conditions is conducive to passivating the grain boundary defects in the bulk phase of the perovskite layer while reducing the probability of a significant increase in the series resistance of the perovskite solar cell.

[0021] In some embodiments of the present application, the ratio of the total molar concentration of the ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt in the passivation solution to the molar concentration of the perovskite in the perovskite solution is 0.02%-2%. Thus, while effectively passivating the defects of the perovskite layer, it is beneficial to reduce the probability of a significant increase in the series resistance of the perovskite solar cell, thereby improving the photoelectric performance of the perovskite solar cell.

[0022] In a third aspect, the present application provides an electrical device, comprising: the perovskite solar cell described in the first aspect, or a perovskite solar cell manufactured by the method described in the second aspect.

[0023] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the specific implementation methods of the present application or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0025] Figure 1 A schematic diagram of the structure of a perovskite layer and a passivation layer in a perovskite solar cell according to an embodiment of the present application;

[0026] Figure 2 A schematic diagram of the structure of a perovskite solar cell according to an embodiment of the present application;

[0027] Figure 3 A schematic structural diagram of a perovskite solar cell according to another embodiment of the present application;

[0028] Figure 4 XPS spectra of the perovskite layers formed in Comparative Examples 1 and 3 of the present application;

[0029] Description of reference numerals:

[0030] 1-perovskite layer; 2-passivation layer; 3-first carrier transport layer; 4-second carrier transport layer; 5-substrate; 6-first electrode layer; 7-second electrode layer. DETAILED DESCRIPTION

[0031] The following is a detailed description of the embodiments of the technical solution of the present application. The following embodiments are only used to more clearly illustrate the technical solution of the present application, and are therefore only used as examples, and cannot be used to limit the scope of protection of the present application.

[0032] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0033] For simplicity, only some numerical ranges are specifically disclosed herein. However, any lower limit can be combined with any upper limit to form an unspecified range; and any lower limit can be combined with other lower limits to form an unspecified range, and any upper limit can be combined with any other upper limit to form an unspecified range. In addition, each separately disclosed point or single value can itself be combined as a lower limit or upper limit with any other point or single value or with other lower limits or upper limits to form an unspecified range.

[0034] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned figure descriptions and any variations thereof are intended to cover non-exclusive inclusions.

[0035] As the global ecological environment and energy shortage problems become increasingly severe, solar photovoltaic power generation has received widespread attention. As the third-generation new solar cell, perovskite cells have become a rising star in the field of solar cells with their advantages of low cost, simple preparation process, and high efficiency. As the light absorption layer of perovskite solar cells, the quality of the perovskite layer directly affects the photoelectric performance and stability of perovskite solar cells. The perovskite layer is composed of a number of closely arranged perovskite grains, and the grain boundaries are between adjacent perovskite grains. However, there are many defects on the surface of the perovskite layer and at the grain boundaries of the perovskite grains. The presence of the above defects causes the loss of photoelectric conversion efficiency and reduces the photoelectric conversion efficiency of perovskite solar cells. At the same time, the perovskite layer is sensitive to water vapor. When the perovskite solar cell is exposed to a water vapor environment, the perovskite layer is prone to decomposition, which sharply reduces the photoelectric performance and stability of the perovskite solar cell. This is not conducive to the commercialization of perovskite solar cells.

[0036] In view of the above problems, in the present application, ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt are dispersed in the perovskite layer, and a passivation layer is arranged on at least one side of the surface of the perovskite layer, so that the passivation layer includes at least one of phthalocyanine, porphyrin, crown ether, phthalocyanine derivatives, porphyrin derivatives, and crown ether derivatives, so that the two can play a synergistic role. On the one hand, ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt can be used to passivate the internal grain boundaries of the bulk phase of the perovskite layer to reduce the defect state density in the bulk phase of the perovskite layer; on the other hand, the material included in the passivation layer can be used to passivate the surface defects of the perovskite layer to reduce the defect state density on the surface of the perovskite layer, while stabilizing the perovskite lattice structure on the surface of the perovskite layer, and making the passivation layer hydrophobic, thereby simultaneously improving the photoelectric performance and stability of the perovskite solar cell.

[0037] The perovskite solar cell disclosed in the present application belongs to a photovoltaic cell, and the perovskite solar cell disclosed in the embodiment of the present application can be used as a power source for electrical devices, or can be assembled into a photovoltaic power generation system and store electrical energy in an energy storage system composed of energy storage batteries. Electrical devices may include street lamps, signal indicator lights, insect killer lamps, electric fans, electric toys, electric tools, battery cars, electric cars, ships, spacecraft, etc., wherein electric toys may include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc., and spacecraft may include airplanes, rockets, space shuttles, and spacecraft, etc.; photovoltaic power generation systems may include large-scale ground photovoltaic power generation systems, distributed photovoltaic power generation and building-integrated photovoltaic power generation systems, etc.

[0038] The first aspect of the present application provides a perovskite solar cell, comprising: a perovskite layer, in which ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetate are dispersed; a passivation layer, which is located on at least one side surface of the perovskite layer, and the passivation layer includes at least one of phthalocyanine, porphyrin, crown ether, phthalocyanine derivatives, porphyrin derivatives, and crown ether derivatives.

[0039] refer to Figure 1 It is understood that in the perovskite solar cell disclosed in the present application, ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt are dispersed in the perovskite layer 1, and the passivation layer 2 includes at least one of phthalocyanine, porphyrin, crown ether, phthalocyanine derivatives, porphyrin derivatives, and crown ether derivatives. Figure 2 or Figure 3 It is understood that the perovskite solar cell generally also includes a first carrier transport layer 3 and a second carrier transport layer 4, and the perovskite layer 1 is arranged between the first carrier transport layer 3 and the second carrier transport layer 4, wherein the passivation layer 2 is provided on at least one of the side of the perovskite layer 1 close to the first carrier transport layer 3 and the side close to the second carrier transport layer 4.

[0040] In the present application, conventional technical means can be used to analyze the components in the perovskite layer and the passivation layer. For example, the analysis method used may include liquid chromatography-mass spectrometry (HPLC-MS), nuclear magnetic resonance (NMR), EDS energy spectrum analysis, etc. As a specific example, liquid chromatography-mass spectrometry (HPLC-MS) combined with nuclear magnetic resonance (NMR) can be used to analyze the materials of the passivation layer and the perovskite layer. The specific operation may include: after disassembling the perovskite solar cell, removing the carrier transport layer and other structures by using tape, solvent, etc. to expose at least one of the perovskite layer and the passivation layer, and then using the perovskite layer and the passivation layer to analyze the passivation layer and the passivation layer respectively. A good solvent is used to dissolve the two-layer structure respectively to obtain two liquid samples to be tested. For example, the anti-solvent of the perovskite layer, such as chlorobenzene, can be used to dissolve the passivation layer to obtain the passivation layer liquid sample to be tested, and then the good solvent of the perovskite layer, such as N,N-dimethylformamide (DMF), can be used to dissolve the perovskite layer to obtain the perovskite layer liquid sample to be tested. Alternatively, the anti-solvent of the passivation layer can be used to dissolve the perovskite layer to obtain the perovskite layer liquid sample to be tested, and then the good solvent of the passivation layer can be used to dissolve the passivation layer to obtain the passivation layer liquid sample to be tested. The two liquid samples to be tested are respectively subjected to HPLC-MS and NMR test analysis to determine whether the perovskite layer and the passivation layer contain the material within the given range.

[0041] The ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt in the perovskite layer can passivate the internal grain boundaries of the bulk phase of the perovskite layer and reduce the defect state density in the bulk phase of the perovskite layer; the phthalocyanine, porphyrin, crown ether, phthalocyanine derivatives, porphyrin derivatives or crown ether derivatives located on the surface of the perovskite layer can passivate the surface defects of the perovskite layer and reduce the defect state density on the surface of the perovskite layer. The reduction of the defect state density in the bulk phase and the surface of the perovskite layer is conducive to reducing the degree of carrier recombination and improving the performance of the perovskite layer. The photoelectric performance of high perovskite solar cells; further, the phthalocyanine, porphyrin, crown ether, phthalocyanine derivatives, porphyrin derivatives or crown ether derivatives located on the surface of the perovskite layer can not only combine with the metal cations in the perovskite material located on the surface of the perovskite layer through chelation, thereby stabilizing the perovskite lattice structure on the surface of the perovskite layer and improving the stability of the perovskite layer (taking ABX3 type perovskite material as an example, A is usually a monovalent cation, such as methylamine, guanidine, Cs + , Rb + etc., B is usually a divalent metal cation, such as Pb 2+ Sn 2+ etc., X is usually a halogen anion, such as Cl - 、Br - 、Iodide ion I - The above components in the passivation layer can be combined with the B-site cations in the perovskite material located on the surface of the perovskite layer through chelation, stabilize the inorganic octahedral framework of BX, and improve the stability of the perovskite layer). At the same time, the passivation layer can also be made hydrophobic, which can inhibit water from entering the perovskite layer, and further improve the stability of the perovskite layer. Compared with the introduction of ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt into the perovskite layer alone, and the passivation layer is set separately, the combination of the two can play a better synergistic effect, improve the improvement effect on the photoelectric performance and stability of the perovskite solar cell, and make the perovskite solar cell have both good photoelectric performance and stability.

[0042] The perovskite solar cell of the first aspect of the present application has the following beneficial effects: it is not only conducive to reducing the defect state density of the bulk and surface of the perovskite layer, reducing the degree of carrier recombination, and improving the photoelectric performance of the perovskite solar cell, but also can stabilize the perovskite lattice structure on the surface of the perovskite layer, and make the passivation layer hydrophobic, which can inhibit moisture from entering the perovskite layer, improve the stability of the perovskite layer and the perovskite solar cell, so that the perovskite solar cell has good photoelectric performance and stability.

[0043] In some embodiments of the present application, the ratio of the total molar amount of ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt in the perovskite layer 1 to the molar amount of perovskite in the perovskite layer 1 may be less than or equal to 1.2%.

[0044] For example, the ratio of the total molar amount of EDTA and / or EDTA salt in the perovskite layer to the molar amount of perovskite in the perovskite layer can be 0.01%, 0.02%, 0.05%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.1%, 1.2%, etc., or can be a range consisting of any of the above values. The total molar amount of ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt in the perovskite layer can be determined by combining one or more analytical methods such as liquid chromatography-mass spectrometry (HPLC-MS), nuclear magnetic resonance (NMR), EDS energy spectrum analysis, inductively coupled plasma emission spectrometry (ICP), etc. For example, HPLC-MS and NMR can be combined to analyze the types of perovskite materials, ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt in the perovskite layer, and then EDS energy spectrum analysis or ICP test can be used to obtain the ratio of the total molar amount of ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt in the perovskite layer to the molar amount of perovskite in the perovskite layer according to the molar ratio of unique elements (such as O) in ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt to the unique elements (such as Pb) in the perovskite material. In the actual preparation process, ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt in the perovskite layer can be introduced through the perovskite solution or through the passivation solution. The molecules of ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt are relatively small and contain a large number of coordinated atoms, which can enter the perovskite layer to increase the vacancy formation energy and passivate most of the defects in the bulk phase of the perovskite layer. It can be understood that ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt can be uniformly dispersed in the perovskite layer, or can present different dispersion concentrations in the thickness direction of the perovskite layer. For example, when the passivation layer is formed only on one of the two sides of the perovskite layer that are oppositely disposed, the total concentration of ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt in the perovskite layer can gradually decrease in the direction away from the passivation layer. The relative molar amount of ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt to perovskite in the perovskite layer is controlled to meet the given range requirements. On the one hand, the passivation effect on the grain boundary defects in the bulk phase of the perovskite layer can be improved by increasing the content of ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt in the perovskite layer. On the other hand, it is also beneficial to avoid excessive accumulation of ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt at the perovskite grain boundaries and interfaces to increase the series resistance of the perovskite solar cell and thus affect the battery performance.

[0045] In the present application, the relative molar amounts of ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt and perovskite in the perovskite layer are controlled to meet the given range requirements, which is beneficial to passivating the grain boundary defects in the bulk phase of the perovskite layer while reducing the probability of a significant increase in the series resistance of the perovskite solar cell, thereby further improving the photoelectric performance of the perovskite solar cell.

[0046] In some embodiments of the present application, the thickness of the passivation layer 2 may be 10 nm-80 nm.

[0047] For example, the thickness of the passivation layer can be 10nm, 15nm, 20nm, 25nm, 30nm, 35nm, 40nm, 45nm, 50nm, 55nm, 60nm, 65nm, 70nm, 75nm, 80nm, etc., or can be the range composed of any of the above numerical values. The thickness of the passivation layer can be measured by a scanning electron microscope (SEM) or an ellipsometer. In the present application, increasing the thickness of the passivation layer is conducive to improving the coverage effect of the passivation layer on the surface of the perovskite layer, improving the passivation effect on the surface defects of the perovskite layer, and further suppressing the entry of moisture into the perovskite layer. By controlling the thickness of the passivation layer to meet the given range, not only can the passivation effect on the surface defects of the perovskite layer be further improved, and further suppressing the entry of moisture into the perovskite layer, it is also conducive to avoiding the problem that the series resistance is significantly increased due to the excessive thickness of the passivation layer, thereby seriously reducing the filling factor of the perovskite solar cell.

[0048] In the present application, by controlling the thickness of the passivation layer to meet the given range, the surface defects of the perovskite layer can be further passivated while reducing the probability of a significant increase in the series resistance of the perovskite solar cell, reducing the series resistance of the perovskite solar cell, and inhibiting the entry of moisture into the perovskite layer, thereby improving the photoelectric performance and stability of the perovskite solar cell.

[0049] In some embodiments of the present application, the perovskite solar cell may further include a substrate, the perovskite layer 1 is located on one side of the substrate, and a passivation layer 2 may be provided on a surface of the perovskite layer 1 facing away from the substrate.

[0050] refer to Figure 2 or Figure 3 As shown, under normal circumstances, a perovskite solar cell may include a substrate 5, a first electrode layer 6, a first carrier transport layer 3, a perovskite layer 1, a second carrier transport layer 4, and a second electrode layer 7 which are arranged in sequence. The side of the perovskite layer 1 facing away from the substrate 5 is usually called the upper surface. In practical applications, the interface defects of the perovskite layer 1 are mainly distributed on its upper surface, and water vapor also mostly enters the perovskite layer 1 from the upper surface of the perovskite layer 1. By providing a passivation layer 2 on the surface of the perovskite layer 1 facing away from the substrate 5, that is, providing a passivation layer 2 between the perovskite layer 1 and the first carrier transport layer 3, it is beneficial to further passivate the surface defects of the perovskite layer 1 and improve the photoelectric performance and stability of the perovskite solar cell.

[0051] For some specific examples, see Figure 2As shown, the passivation layer 2 can be provided only on the surface of the perovskite layer 1 facing away from the substrate 5, and no passivation layer is provided on the side of the perovskite layer 1 close to the substrate 5. Compared with providing the passivation layer on the surface of the perovskite layer facing the substrate, it is more effective to improve the photoelectric performance and stability of the perovskite solar cell; compared with providing the passivation layer on both sides of the perovskite layer, providing the passivation layer only on the surface of the perovskite layer facing away from the substrate is not only conducive to the perovskite solar cell to obtain better photoelectric performance and stability, but also can simplify the preparation process.

[0052] In some embodiments of the present application, the perovskite solar cell may further include a metal electrode layer, and the passivation layer may be provided on a surface of the perovskite layer 1 facing the metal electrode layer.

[0053] refer to Figure 2 or Figure 3 , at least one of the first electrode layer 6 and the second electrode layer 7 in the perovskite solar cell may be a metal electrode layer. Generally, the electrode layer material of the perovskite solar cell may include an organic conductive material or an inorganic conductive material or an organic-inorganic mixed conductive material. For example, organic conductive materials include but are not limited to PEDOT (polymer of 3,4-ethylenedioxythiophene), polythiophene, polyacetylene, etc.; inorganic conductive materials include but are not limited to FTO (fluorine-doped SnO2 conductive glass), ITO (indium tin oxide), AZO (aluminum-doped zinc oxide transparent conductive glass), metals, carbon derivatives, etc. As a specific example, when a metal electrode layer is present, such as when the second electrode layer 6 is a metal electrode layer, the metal electrode layer may generate metal ions due to corrosion or other reasons during long-term use. When the metal ions migrate through the carrier transport layer to the perovskite layer, the perovskite layer is easily degraded, which is not conducive to the structural stability of the perovskite solar cell. By providing a passivation layer on the surface of the perovskite layer facing the metal electrode layer, phthalocyanine, porphyrin, crown ether, phthalocyanine derivatives, porphyrin derivatives or crown ether derivatives can be combined with the metal ions of the metal electrode layer through chelation, thereby inhibiting the migration of metal ions into the perovskite layer and improving the long-term stability of the perovskite layer.

[0054] By providing a passivation layer on the surface of the perovskite layer facing the metal electrode layer, it is helpful to inhibit metal ions generated by corrosion of the metal electrode layer from entering the perovskite layer, delay the degradation of the perovskite layer, and further improve the stability of the perovskite solar cell.

[0055] In some embodiments of the present application, the structural formula of the perovskite material in the perovskite layer 1 may be ABX3 and / or A2CDX6, wherein A is a positive monovalent cation, which may include a methylamine group (CH3NH3 + , referred to as MA + ), carboxamidyl (HC(NH2)2+ , referred to as FA + ), cesium ion (Cs + ), rubidium (Rb + ) at least one of; B is a positive divalent metal cation, which may include Pb 2+ Sn 2+ At least one of; C is a positive monovalent metal cation, which may include Ag + ; D is a positive trivalent metal cation, which may include Bi 3+ ; X can be a halogen ion Cl - Br - ,I - Optionally, the A-position cation may be at least one of a methylamine group and a guanidine group, and the phthalocyanine, porphyrin, crown ether, phthalocyanine derivative, porphyrin derivative or crown ether derivative in the passivation layer can form a hydrogen bond with the methylamine group or guanidine group in the perovskite layer, thereby inhibiting its migration, improving the structural stability of the perovskite layer, and improving the stability of the perovskite solar cell.

[0056] In some embodiments of the present application, the band gap of the perovskite layer 1 can be 1.20 eV-2.30 eV. The band gap of the perovskite layer can be measured by an ultraviolet visible absorption test (UV-vis) method. The band gap of the perovskite layer meets the given range and can absorb most of the light in the solar spectrum, from ultraviolet to infrared, and can be effectively converted into electrical energy.

[0057] In some embodiments of the present application, the thickness of the perovskite layer 1 can be 200nm-1000nm. For example, the thickness of the perovskite layer can be 200nm, 300nm, 400nm, 500nm, 600nm, 700nm, 800nm, 900nm, 1000nm, etc., or can be a range composed of any of the above numerical values. The thickness of the perovskite layer can be measured by a scanning electron microscope (SEM). Increasing the thickness of the perovskite layer is conducive to improving its light absorption efficiency, and controlling the thickness of the perovskite layer to meet the given range is conducive to obtaining a higher light absorption efficiency, and is also conducive to avoiding the risk of increased internal defects due to the increase in the thickness of the perovskite layer, thereby further improving the photoelectric conversion efficiency of the perovskite solar cell.

[0058] In some embodiments of the present application, ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt may be dispersed in the passivation layer 2, and the ratio of the total molar amount of ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt in the perovskite layer 1 and the passivation layer 2 to the molar amount of perovskite in the perovskite layer 1 may be less than or equal to 2%.

[0059] For example, the ratio of the total molar amount of ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt in the perovskite layer and the passivation layer to the molar amount of perovskite in the perovskite layer can be 0.01%, 0.02%, 0.05%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%, 1.6%, 1.7%, 1.8%, 1.9%, 2%. The total molar amount of ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt in the perovskite layer and the passivation layer can also be determined by combining one or more analytical methods such as liquid chromatography-mass spectrometry (HPLC-MS), nuclear magnetic resonance (NMR), EDS energy spectrum analysis, inductively coupled plasma emission spectrometry (ICP), etc. The ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt in the passivation layer can passivate the surface defects of the perovskite layer. Increasing the total content of ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt in the perovskite layer and the passivation layer is beneficial to improving the passivation effect on grain boundary defects and surface defects in the perovskite layer.

[0060] Controlling the total molar amount of ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt in the perovskite layer and the passivation layer to meet the given range is beneficial for further passivating the surface defects while passivating the grain boundary defects in the bulk phase of the perovskite layer, and can also reduce the probability of a significant increase in the series resistance of the perovskite solar cell due to the introduction of ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt, thereby facilitating further improvement of the photoelectric performance and stability of the perovskite solar cell.

[0061] It can be understood that the ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt in the perovskite layer can be introduced when the perovskite layer is formed, such as dispersing ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt in the perovskite solution to prepare the perovskite layer; it can also be introduced when the passivation layer is formed, in which case ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt can be introduced into the passivation layer solution, and at the same time, at least one of phthalocyanine, porphyrin, crown ether, phthalocyanine derivatives, porphyrin derivatives, and crown ether derivatives can be introduced, and after the passivation solution is coated on the surface of the perovskite layer, annealing is performed. During the annealing process, since the ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt molecules are relatively small and contain a large number of coordinating atoms, most of the ethylenediaminetetraacetic acid in the passivation solution Amine tetraacetic acid and / or ethylenediamine tetraacetate can migrate into the perovskite layer, increase the vacancy formation energy, and passivate most of the defects in the bulk phase of the perovskite layer. Only a small amount of ethylenediamine tetraacetic acid and / or ethylenediamine tetraacetate remains in the passivation layer, while the molecules of phthalocyanine / porphyrin / crown ether and their derivatives are relatively large and can only exist on the surface of the perovskite layer. The ethylenediamine tetraacetic acid and / or ethylenediamine tetraacetate and phthalocyanine / porphyrin / crown ether and their derivatives remaining in the passivation layer can passivate the surface defects of the perovskite layer while stabilizing the perovskite lattice structure on the surface of the perovskite layer, and inhibit the entry of water and metal ions generated by corrosion of the metal electrode layer into the perovskite layer, thereby significantly improving the stability of the perovskite layer and perovskite solar cells.

[0062] In some embodiments of the present application, the number of oxygen in the ring-forming elements of the crown ether and the crown ether derivatives is independently 4-10. The crown ethers and crown ether derivatives that meet the given conditions have good hydrophobicity, which is beneficial to further inhibit the entry of water into the perovskite layer. For example, the number of oxygen in the ring-forming elements of the crown ether can be 4, 5, 6, 7, 8, 9, 10, and the number of oxygen in the ring-forming elements of the crown ether derivatives can be 4, 5, 6, 7, 8, 9, 10; illustratively, the crown ether can include but is not limited to 12-crown-4 (CAS: 294-93-9), 15-crown-5 (CAS: 33100-27-5), 18-crown-6 (CAS: 17455-13-9), 21-crown-7 (CAS: 33089-36-0), etc. At least one of the crown ether derivatives may include but are not limited to benzo-15-crown-5 (CAS: 14098-44-3), benzo-18-crown-6 (CAS: 14098-24-9), dibenzo-18-crown-6 (CAS: 14187-32-7), dibenzo-21-crown-7 (CAS: 14098-41-0), dibenzo-24-crown-8 (CAS: 14174-09-5), dibenzo-30-crown-10 (CAS: 17455-25-3), etc.

[0063] In some embodiments of the present application, the crown ether derivatives may include R1, R2, R3, R4, R5, and R6 can independently include any one of hydrogen, halogen, alkyl, phenyl, naphthyl, alkoxy, phenoxy, amino, hydroxyl, carboxyl, sulfonic acid, pyridyl, and thienyl, and the ring-forming elements in the above crown ether derivatives contain 6 oxygen elements. It is understood that the alkyl, phenyl, naphthyl, alkoxy, phenoxy, amino, sulfonic acid, pyridyl, and thienyl that R1, R2, R3, R4, R5, and R6 can be independently substituted or unsubstituted groups, and the groups represented by R1, R2, R3, R4, R5, and R6 can be the same, partially the same, or different.

[0064] In some embodiments of the present application, porphyrin derivatives may include M1 may be a metal element; R7 may include any one of hydrogen, halogen, alkyl, phenyl, naphthyl, alkoxy, phenoxy, amino, hydroxyl, carboxyl, sulfonic acid, pyridyl, and thienyl. It is understood that the alkyl, phenyl, naphthyl, alkoxy, phenoxy, amino, sulfonic acid, pyridyl, and thienyl selected from R7 may be independently substituted or unsubstituted groups; R8, R9, and R 10 , R 11 can independently include any one of hydrogen, halogen, alkyl, alkenyl, alkyl, and alkoxy. It is understood that R8, R9, R 10 , R 11 The optional alkyl, alkenyl, phenyl and alkoxy groups may be independently substituted or unsubstituted groups, and R8, R9, R 10 , R 11 The groups represented may be the same, partially the same or different; alternatively, M1 may include at least one of Na, Cu, Fe, Co, Ni, Ca, and Mg. Exemplarily, porphyrin derivatives may include, but are not limited to, at least one of 5,10,15,20-tetraphenylporphyrin copper (CAS: 14172-91-9), tetrakis (4-aminophenyl) porphyrin copper (CAS: 67595-97-5), tetrakis (4-pyridyl) porphyrin copper (CAS: 14518-23-1), tetrakis (4-methoxyphenyl) porphyrin copper (CAS: 24249-30-7), tetrakis (4-carboxylphenyl) porphyrin copper (CAS: 41699-93-8), and the like.

[0065] In some embodiments of the present application, phthalocyanine derivatives may include M2 can be a metal element; R 12 , R 13 , R 14, R 15 can independently include any one of hydrogen, halogen, alkyl, phenyl, naphthyl, alkoxy, phenoxy, amino, hydroxyl, carboxyl, sulfonic acid, and pyridyl. It is understood that R 12 , R 13 , R 14 , R 15 The optional alkyl, phenyl, naphthyl, alkoxy, phenoxy, amino, sulfonic acid, pyridyl, thienyl may be independently substituted or unsubstituted, R 12 , R 13 , R 14 , R 15 The groups represented may be the same, partially the same or different; alternatively, M2 may include at least one of Na, Cu, Fe, Co, Ni, Ca, Mg, and Zn. Exemplary, phthalocyanine derivatives may include, but are not limited to, at least one of 2,9,16,23-tetraphenoxy copper phthalocyanine (CAS: 91083-47-5), tetracarboxylic copper phthalocyanine (CAS: 16337-64-7), perfluoro copper phthalocyanine (CAS: 14916-87-1), octahydroxy copper phthalocyanine (CAS: 123934-46-3), tetra-tert-butyl magnesium phthalocyanine (CAS: 39001-64-4), tetra-tert-butyl-2,3-naphthalocyanine zinc (CAS: 39049-43-9), and tetraamino copper phthalocyanine (CAS: 28632-30-6).

[0066] The porphyrin derivatives and phthalocyanine derivatives within the given range of the present application have excellent hydrophobicity and good conductivity. Introducing at least one of the porphyrin derivatives and phthalocyanine derivatives within the given range into the passivation layer is beneficial to further passivate the surface defects of the perovskite layer, inhibit the entry of moisture into the perovskite layer, and improve the stability of the perovskite layer.

[0067] In some embodiments of the present application, ethylenediaminetetraacetate may include at least one of sodium ethylenediaminetetraacetate (CAS: 6381-92-6), copper ethylenediaminetetraacetate (CAS: 14025-15-1), iron ethylenediaminetetraacetate (CAS: 15708-41-5), calcium ethylenediaminetetraacetate (CAS: 23411-34-9), magnesium ethylenediaminetetraacetate (CAS: 14402-88-1), cobalt ethylenediaminetetraacetate (CAS: 15137-09-4), and nickel ethylenediaminetetraacetate (CAS: 11079-07-5). Introducing ethylenediaminetetraacetate in the given range into the perovskite layer can effectively passivate the grain boundary defects of the perovskite.

[0068] In some embodiments of the present application, the perovskite solar cell may be either a formal perovskite solar cell or an inverted perovskite solar cell.

[0069] Exemplary, reference Figure 2 or Figure 3 It is understood that when the perovskite solar cell is a formal perovskite solar cell, the first carrier transport layer 3 is an electron transport layer, the second carrier transport layer 4 is a hole transport layer, the electron transport layer material may include at least one of SnO2, TiO2, ZnO, and Al2O3, and the hole transport layer material may include at least one of 2,2',7,7'-tetrakis[N,N-di(4-methoxyphenyl)amino]-9,9'-spirobifluorene (Spiro-OMeTAD), 3,4-ethylenedioxythiophene-methoxytriphenylamine (EDOT-OMeTPA), and N-(4-phenylamino)carbazole-spirobifluorene (CzPAF-SBF).

[0070] Exemplary, reference Figure 2 or Figure 3 It is understood that when the perovskite solar cell can be an inverted perovskite solar cell, the first carrier transport layer 3 is a hole transport layer, the second carrier transport layer 4 is an electron transport layer, and the hole transport layer material can include poly [bis (4-phenyl) (2,4,6-trimethylphenyl) amine] (PTAA), poly (3,4-ethylenedioxythiophene): polystyrene sulfonic acid (PEDOT:PSS), poly-3 hexylthiophene (P3HT), nickel oxide (NiO x ), cuprous iodide (CuI), cuprous oxide (CuO), the electron transport layer material may include [6,6]-phenyl C 61 Methyl butyrate (PC 61 BM), [6,6]-phenyl C 71 Methyl butyrate (PC 71 BM), fullerene and its derivatives.

[0071] In some embodiments of the present application, reference Figure 2 or Figure 3 It is understood that the substrate 5 of the perovskite solar cell may include glass and a flexible substrate, and the flexible substrate may include polyethylene naphthalate (PEN) and polyethylene terephthalate (PET). When one of the first electrode layer 6 and the second electrode layer 7 is a metal electrode layer, the other may be a transparent conductive layer, and the transparent conductive layer may include fluorine-doped tin oxide (FTO), indium tin oxide (ITO), aluminum-doped zinc oxide (AZO), boron-doped zinc oxide (BZO), and indium zinc oxide (IZO).

[0072] The second aspect of the present application provides a method for preparing a perovskite solar cell, which includes: forming a perovskite layer, so that ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt are dispersed in the perovskite layer; forming a passivation layer, so that the passivation layer is located on at least one side of the surface of the perovskite layer, and the passivation layer includes at least one of phthalocyanine, porphyrin, crown ether, phthalocyanine derivatives, porphyrin derivatives, and crown ether derivatives. Phthalocyanine, porphyrin, crown ether, phthalocyanine derivatives, porphyrin derivatives, and crown ether derivatives are used to passivate the surface defects of the perovskite layer and belong to surface passivation materials. It should be noted that the characteristics and effects described for the perovskite solar cell are also applicable to the preparation method of the perovskite solar cell, and will not be repeated here. In general, the method for preparing a perovskite solar cell in the second aspect of the present application is conducive to improving the photoelectric performance and stability of the perovskite solar cell.

[0073] In some embodiments of the present application, a perovskite layer may be formed first, and then a passivation layer may be formed on the surface of the perovskite layer.

[0074] In some other embodiments of the present application, a passivation layer may be formed first, and then a perovskite layer may be formed on the surface of the passivation layer.

[0075] In some other embodiments of the present application, a first passivation layer may be formed first, and then a perovskite layer may be formed on the surface of the first passivation layer, and then a second passivation layer may be formed on the surface of the perovskite layer facing away from the first passivation layer, wherein the materials of the first passivation layer and the second passivation layer may be the same or different, and the thicknesses of the first passivation layer and the second passivation layer may be the same or different.

[0076] In some embodiments of the present application, the perovskite layer may be formed using a perovskite solution, and the passivation layer may be formed using a passivation solution. At least one of the perovskite solution and the passivation solution may contain ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetate.

[0077] For example, as some specific examples, when the perovskite solution contains ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt, the passivation solution may contain ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt, or may not contain ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt; as some other specific examples, ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt may be dispersed only in the passivation solution, as described above, after the passivation solution is coated on the surface of the perovskite layer, annealing is performed, and during the annealing process, most of the ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt in the passivation solution can migrate to the perovskite layer. The perovskite solar cell prepared by the above method can achieve the effect of ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt dispersed in the perovskite layer.

[0078] Specifically, the step of forming the perovskite layer using the perovskite solution may include coating the perovskite solution and first annealing; the step of forming the passivation layer using the passivation solution may include coating the passivation solution and second annealing. In addition, when the passivation layer is formed on the surface of the perovskite layer, if the passivation solution contains ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt, the perovskite layer can be prepared by a solution method or by other methods, such as chemical vapor deposition.

[0079] In some embodiments of the present application, in the passivation solution, the sum of the concentrations of phthalocyanine, porphyrin, crown ether, phthalocyanine derivatives, porphyrin derivatives, and crown ether derivatives may be 0.1 mg / mL-8 mg / mL.

[0080] For example, in the passivation solution, the concentration sum of phthalocyanine, porphyrin, crown ether, phthalocyanine derivatives, porphyrin derivatives, and crown ether derivatives used as surface passivation materials can be 0.1 mg / mL, 0.5 mg / mL, 1 mg / mL, 2 mg / mL, 3 mg / mL, 4 mg / mL, 5 mg / mL, 6 mg / mL, 7 mg / mL or 8 mg / mL, etc., or can be the range composed of any of the above numerical values. The concentration of the surface passivation material in the passivation solution directly affects the thickness of the passivation layer. Increasing the concentration of the surface passivation material in the passivation solution is conducive to improving the coverage effect of the passivation layer on the surface of the perovskite layer, and improving the passivation effect on the surface defects of the perovskite layer.

[0081] Controlling the concentrations of phthalocyanine, porphyrin, crown ether, phthalocyanine derivatives, porphyrin derivatives, and crown ether derivatives in the passivation solution to meet the given range requirements is beneficial to regulating the thickness of the passivation layer so that the passivation layer has an appropriate thickness, which is beneficial for effectively passivating the surface defects of the perovskite layer and inhibiting the entry of moisture into the perovskite layer, and is also beneficial for reducing the probability of a significant increase in the series resistance of the perovskite solar cell, thereby further improving the photoelectric performance and stability of the perovskite solar cell.

[0082] In some embodiments of the present application, the ratio of the total molar concentration of ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt in the perovskite solution to the molar concentration of perovskite in the perovskite solution may be 0.02%-1.2%.

[0083] When the perovskite layer is prepared by a solution method, ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt can be introduced into the perovskite solution. At this time, the ratio of the total molar concentration of ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt in the perovskite solution to the molar concentration of perovskite in the perovskite solution can be 0.02%, 0.05%, 0.10%, 0.20%, 0.40%, 0.60%, 0.80%, 1.00%, 1.20%, etc., or can be a range composed of any of the above values, which can be selected as 0.4%-1%. As a specific example, when the molar concentration of perovskite in the perovskite solution is 1.5 mol / L, the total molar concentration of ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt in the perovskite solution can be 0.0003 mol / L-0.018 mol / L.

[0084] Controlling the total molar concentration of ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt in the perovskite solution to meet the given range is beneficial to passivating the grain boundary defects in the bulk phase of the perovskite layer while reducing the probability of a significant increase in the series resistance of the perovskite solar cell, thereby improving the photoelectric performance of the perovskite solar cell.

[0085] In some embodiments of the present application, the ratio of the total molar concentration of EDTA and / or EDTA salt in the passivation solution to the molar concentration of perovskite in the perovskite solution may be 0.02%-2%.

[0086] For example, the ratio of the total molar concentration of ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt in the passivation solution to the molar concentration of perovskite in the perovskite solution can be 0.02%, 0.05%, 0.10%, 0.40%, 0.80%, 1.20%, 1.60%, 1.80%, 2%, etc., or can be a range composed of any of the above values, which can be selected as 0.60%-1.5%. As a specific example, when the molar concentration of perovskite in the perovskite solution is 1.5 mol / L, the total molar concentration of ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt in the passivation solution can be 0.0003 mol / L-0.03 mol / L. When a passivation solution is coated on the perovskite layer to form a passivation layer, ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt in the passivation solution can migrate to the perovskite layer during the annealing process, and only a small amount remains in the passivation layer. In the actual operation process, the concentration of ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt in the passivation solution can be flexibly adjusted according to whether the perovskite solution contains ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt, and the concentration of ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt in the perovskite solution. In addition, as a specific example, when a first passivation layer is formed in advance, a perovskite layer is then formed on the surface of the first passivation layer, and then a second passivation layer is formed on the surface of the perovskite layer away from the first passivation layer. The total molar concentration of ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt in the passivation solution (i.e., the passivation solution used to form the second passivation layer) can be controlled to meet the given range requirements.

[0087] Controlling the total molar concentration of ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt in the passivation solution to meet the given range is beneficial to effectively passivating the defects of the perovskite layer while reducing the probability of a significant increase in the series resistance of the perovskite solar cell, thereby improving the photoelectric performance of the perovskite solar cell.

[0088] In some embodiments of the present application, the method for preparing a perovskite solar cell may further include the following steps: forming a first electrode layer on one side of the substrate; forming a first carrier transport layer on the side of the first electrode layer facing away from the substrate, so that a perovskite layer or a passivation layer is formed on the side of the first carrier transport layer facing away from the first electrode layer; forming a second carrier transport layer on the side of the passivation layer or the perovskite facing away from the first electrode layer, and forming a second electrode layer on the side of the second carrier transport layer facing away from the first electrode layer. Among them, the process conditions controlled when preparing each layer structure of the perovskite solar cell can be conventionally selected in the art.

[0089] The third aspect of the present application provides an electrical device, which includes: the perovskite solar cell of the first aspect, or the perovskite solar cell prepared by the method of the second aspect. The electrical device may include lighting elements, display elements, mobile devices, etc., and may specifically include street lights, signal indicators, insect killers, electric fans, electric toys, electric tools, battery vehicles, electric vehicles, ships, spacecraft, etc., wherein the electric toys may include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc., and the spacecraft may include airplanes, rockets, space shuttles, and spacecrafts, etc.; the photovoltaic power generation system may include a large-scale ground photovoltaic power generation system, a distributed photovoltaic power generation and building integrated photovoltaic power generation system, etc.

[0090] In order to make the technical problems, technical solutions and beneficial effects solved by the embodiments of the present application clearer, the following will be further described in detail with reference to the embodiments. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means any limitation to the present application and its application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians of the art without paying creative work are within the scope of protection of the present application. If the specific technology or conditions are not indicated in the embodiments, the technology or conditions described in the literature in this area or the product specification are carried out. The reagents or instruments used that do not indicate the manufacturer are all conventional products that can be obtained by commercial purchase.

[0091] Example 1

[0092] This embodiment provides a method for preparing a perovskite solar cell, comprising the following steps:

[0093] Provide FTO conductive glass with a size of 2.0 cm × 2.0 cm;

[0094] The FTO conductive glass was pretreated: the FTO conductive glass was ultrasonically cleaned with deionized water, acetone and isopropanol in sequence, and the ultrasonic cleaning time of each solution was 10 minutes; the FTO conductive glass was blown dry with nitrogen; and then the FTO conductive glass was treated with UV-ozone for 15 minutes.

[0095] Preparation of electron transport layer: dilute a 20wt% SnO2 aqueous colloidal solution with deionized water to obtain a 2.5%wt SnO2 solution, ultrasonically vibrate the solution for 30 minutes and then filter it for later use; drop the solution on the surface of the FTO layer of the FTO conductive glass, rotate at 4000rpm for 20s to obtain a SnO2 liquid film; anneal the SnO2 liquid film at 150°C for 10 minutes to obtain a 30nm thick SnO2 layer.

[0096] Preparation of perovskite layer: 705.34 mg PbI2, 240.8 mg FAI and 33.78 mg MACl were added to a mixed solvent prepared by 100 μL DMSO and 900 μL DMF, and stirred at room temperature for 8 hours to obtain a perovskite solution, in which the molar concentration of perovskite was 1.5 mol / L; the perovskite solution was spin-coated on the electron transport layer at a speed of 5000 rpm for 15 seconds, and 600 uL anisole was added to the rotating sample at the 10th second of the spin coating; after the spin coating, the sample was transferred to a hot stage and annealed at 100°C for 60 minutes to obtain a perovskite layer with a thickness of 550 nm;

[0097] Preparation of a passivation layer: preparing a passivation solution, wherein the passivation solution contains 4 mg / mL of tetrakis(4-methoxyphenyl)porphyrin copper and 0.0003 mol / L of sodium ethylenediaminetetraacetate, and the solvent is an isopropanol solution; spin coating the passivation solution on the perovskite layer at a speed of 5000 rpm for 15 seconds; after the spin coating, transferring the sample to a hot stage and annealing at a temperature of 100° C. for 10 minutes; during the annealing process, a large amount of sodium ethylenediaminetetraacetate in the passivation solution diffuses into the grain boundaries of the bulk phase of the perovskite layer, and the main component of the passivation layer is tetrakis(4-methoxyphenyl)porphyrin copper;

[0098] Preparation of hole transport layer: 72.3 mg spiro-OMeTAD was dissolved in 1 mL chlorobenzene and stirred to completely dissolve; 520 mg / mL lithium bis(trifluoromethanesulfonyl)imide (Li-TFSI) acetonitrile solution was prepared; 18 μL Li-TFSI solution and 29 μL 4-tert-butylpyridine (tBP) were added to the above spiro-OMeTAD solution and stirred to obtain a mixed solution; 100 uL of the mixed solution was taken and spin-coated on the surface of the passivation layer at a speed of 4000 rpm. After the spin coating, a hole transport layer with a thickness of 100 nm was obtained, and the sample was placed in a desiccator for oxidation for 24 hours;

[0099] Preparation of metal electrode layer: The sample was transferred to a vacuum evaporation device at a temperature below 5×10 -4 Pa vacuum conditions, the evaporation rate was 80nm thick Au layer.

[0100] Examples 2 to 32 - Comparative Examples 1 to 7

[0101] The differences between Examples 2 to 32-Comparative Examples 1-7 and Example 1 are detailed in Table 1.

[0102] Among them, the difference between Examples 1-4 is that the concentration of ethylenediaminetetraacetate in the passivation solution is different, see Table 1 for details; the difference between Example 5 and Example 1 is that the type of ethylenediaminetetraacetate is different; the difference between Examples 6-7 and Example 1 is that the concentration of the surface passivation material (the surface passivation material is selected from phthalocyanine, porphyrin, crown ether, phthalocyanine derivatives, porphyrin derivatives, crown ether derivatives) is different; the difference between Examples 8-16 and Example 1 is that the surface passivation material is different; the difference between Examples 17-20 is that the concentration of ethylenediaminetetraacetate in the perovskite solution is different; the difference between Example 21 and Example 17 is that the type of ethylenediaminetetraacetate is different; the difference between Examples 22-23 and Example 17 is that the concentration of the surface passivation material is different; The difference between Examples 24-32 and Example 17 is that the surface passivation materials are different; the difference between Comparative Example 1 and Examples 1-32 is that the perovskite layer does not contain ethylenediaminetetraacetate, and no passivation layer is provided on the surface of the perovskite; the difference between Comparative Example 2 and Example 1 and Examples 6-16, the difference between Comparative Example 3 and Example 17 and Examples 22-32, and the difference between Comparative Example 4 and Examples 1-5 and Examples 17-21 are that only ethylenediaminetetraacetate is contained, and no surface passivation material is contained; the difference between Comparative Example 5 and Example 9 and Example 25, the difference between Comparative Example 6 and Example 11 and Example 27, and the difference between Comparative Example 7 and Example 16 and Example 32 are that no ethylenediaminetetraacetate is contained, and only surface passivation material is contained.

[0103] Performance Test:

[0104] (1) X-ray photoelectron spectroscopy test

[0105] After the perovskite layer is prepared, the sample with the perovskite layer is subjected to an XPS (X-ray photoelectron spectroscopy) test; after the passivation layer is prepared, the sample with the passivation layer is subjected to an XPS (X-ray photoelectron spectroscopy) test.

[0106] (2) Photoelectric conversion efficiency test:

[0107] Using AM 1.5G solar simulator to provide 100mW / cm 2 The volt-ampere characteristic curve of the perovskite solar cell prepared under illumination was measured by a four-channel digital source meter (Keithley 2440) to obtain the open circuit voltage Voc, short circuit current density Jsc, fill factor FF and photoelectric conversion efficiency PCE of the perovskite solar cell, record the photoelectric conversion efficiency PCE of the perovskite solar cell, and take the photoelectric conversion efficiency PCE of the perovskite solar cell in Comparative Example 1 as a benchmark to calculate the growth rate of the photoelectric conversion efficiency PCE in each embodiment and the comparative example, wherein:

[0108] PCE growth rate = (PCE n-PCE0) / PCE0×100%,PCE n PCE0 is the photoelectric conversion efficiency of the perovskite solar cell in the embodiment or comparative example, and PCE0 is the photoelectric conversion efficiency of the perovskite solar cell in comparative example 1.

[0109] (3) Stability test:

[0110] The prepared perovskite solar cell was placed in an environment of 25°C and 45±5% RH, and its photoelectric conversion efficiency was tracked over time to obtain the time T required for its photoelectric conversion efficiency to decay to 80% of the initial efficiency. 80 The initial efficiency is the photoelectric conversion efficiency of the perovskite solar cell before being placed in an environment of 25°C and 45±5%RH.

[0111] The samples prepared in Examples 1-32 and Comparative Examples 1-7 were tested respectively, and the test results are shown in Figure 4 And Table 1.

[0112]

[0113]

[0114]

[0115] Results and Conclusions:

[0116] Comprehensively comparing the XPS test spectra of the perovskite layer samples and passivation layer samples prepared in Examples 1 to 32 and Comparative Examples 1 to 7, combined with the shift of the lead element peak in the spectra, it can be seen that dispersing ethylenediaminetetraacetate in the perovskite layer, or forming a passivation layer including phthalocyanine, porphyrin, crown ether, phthalocyanine derivatives, porphyrin derivatives or crown ether derivatives, are all beneficial to passivating the defects of the perovskite layer. Among them, Figure 4 The XPS spectra of the perovskite layer samples prepared in Comparative Examples 1 and 3 of the present application are as follows: Figure 4 It can be seen that, relative to the perovskite layer sample prepared in Comparative Example 1, the peak of the lead element in the perovskite layer sample prepared in Comparative Example 3 shifted, which indicates that the ethylenediaminetetraacetic acid salt in the perovskite layer reacted with the lead element in the perovskite layer to passivate the lead defects.

[0117] It can be seen from Examples 1 to 32, Comparative Examples 1 to 7 and Table 1 that in the embodiments of the present application, by introducing ethylenediaminetetraacetate into the perovskite layer and forming a passivation layer on the surface of the perovskite layer, the photoelectric conversion efficiency and stability of the perovskite solar cell can be improved at the same time, and compared with only introducing ethylenediaminetetraacetate into the perovskite layer or only forming a passivation layer, the combination of the two schemes in the present application has a better effect on improving the photoelectric conversion efficiency and stability of the perovskite solar cell, which is greater than the sum of the effects of using the two schemes alone. The main reason for the analysis is that the introduction of ethylenediaminetetraacetate into the perovskite layer and the formation of a passivation layer on the surface of the perovskite layer can not only effectively reduce the overall defect state density in the perovskite solar cell, but also produce a synergistic effect; further, under the same conditions, in the perovskite solution or the passivation layer, the photoelectric conversion efficiency and stability of the perovskite solar cell can be improved. Introducing ethylenediaminetetraacetate into the passivation solution can produce good effects, and, at the same ethylenediaminetetraacetate dosage, the effect of introducing ethylenediaminetetraacetate into the perovskite solution is better than that of introducing it into the passivation solution. The main reason for this is that during the annealing process of the passivation layer, most of the ethylenediaminetetraacetate in the passivation solution can migrate to the perovskite layer, and a small amount of ethylenediaminetetraacetate remains in the passivation layer, which weakens the passivation effect on the bulk defects of the perovskite layer to a certain extent; optionally, the ratio of the molar amount of ethylenediaminetetraacetate in the perovskite layer to the molar amount of perovskite in the perovskite layer can be made less than or equal to 1.2%, and further optionally, the ratio of the total molar amount of ethylenediaminetetraacetate in the perovskite layer and the passivation layer to the molar amount of perovskite in the perovskite layer can be made less than or equal to 2%.

[0118] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should all be included in the scope of the claims and specification of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. A perovskite solar cell, characterized in that: include: a perovskite layer, wherein ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt is dispersed in the perovskite layer; A passivation layer, wherein the passivation layer is located on at least one side of the surface of the perovskite layer, and the passivation layer includes at least one of phthalocyanine, porphyrin, crown ether, phthalocyanine derivatives, porphyrin derivatives, and crown ether derivatives.

2. The perovskite solar cell according to claim 1, characterized in that The ratio of the total molar amount of ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt in the perovskite layer to the molar amount of perovskite in the perovskite layer is less than or equal to 1.2%.

3. The perovskite solar cell according to claim 1 or 2, characterized in that: The thickness of the passivation layer is 10nm-80nm.

4. The perovskite solar cell according to any one of claims 1 to 3, characterized in that It also includes a substrate, the perovskite layer is located on one side of the substrate, and the passivation layer is provided on a surface of the perovskite layer that is away from the substrate.

5. The perovskite solar cell according to any one of claims 1 to 4, characterized in that It also includes a metal electrode layer, and the passivation layer is provided on the surface of the perovskite layer on one side close to the metal electrode layer.

6. The perovskite solar cell according to any one of claims 1 to 5, characterized in that Ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt are dispersed in the passivation layer, and the ratio of the total molar amount of ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt in the perovskite layer and the passivation layer to the molar amount of perovskite in the perovskite layer is less than or equal to 2%.

7. The perovskite solar cell according to any one of claims 1 to 6, characterized in that The number of oxygen atoms in the ring-forming elements of the crown ether and the crown ether derivatives is independently 4 to 10.

8. The perovskite solar cell according to any one of claims 1 to 7, characterized in that The crown ether derivatives include R1, R2, R3, R4, R5, and R6 independently include any one of hydrogen, halogen, alkyl, phenyl, naphthyl, alkoxy, phenoxy, amino, hydroxyl, carboxyl, sulfonic acid, pyridyl, and thienyl.

9. The perovskite solar cell according to any one of claims 1 to 8, characterized in that At least one of the following conditions is met: The porphyrin derivatives include and / or M1 is a metal element, R7 includes any one of hydrogen, halogen, alkyl, phenyl, naphthyl, alkoxy, phenoxy, amino, hydroxyl, carboxyl, sulfonic acid, pyridyl, and thienyl, R8, R9, R 10 , R 11 Each independently includes any one of hydrogen, halogen, alkyl, alkenyl, alkyl, and alkoxy; The phthalocyanine derivatives include and / or M2 is a metal element, R 12 , R 13 , R 14 , R 15 Each independently includes any one of hydrogen, halogen, alkyl, phenyl, naphthyl, alkoxy, phenoxy, amino, hydroxyl, carboxyl, sulfonic acid, and pyridyl.

10. The perovskite solar cell according to claim 9, characterized in that: M1 and M2 each independently include at least one of Na, Cu, Fe, Co, Ni, Ca, and Mg.

11. The perovskite solar cell according to claim 10, characterized in that: The ethylenediaminetetraacetate salt includes at least one of sodium ethylenediaminetetraacetate, copper ethylenediaminetetraacetate, iron ethylenediaminetetraacetate, calcium ethylenediaminetetraacetate, magnesium ethylenediaminetetraacetate, cobalt ethylenediaminetetraacetate, and nickel ethylenediaminetetraacetate.

12. A method for preparing a perovskite solar cell according to any one of claims 1 to 11, characterized in that: include: forming a perovskite layer, wherein ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt is dispersed in the perovskite layer; A passivation layer is formed so that the passivation layer is located on at least one side of the surface of the perovskite layer, and the passivation layer includes at least one of phthalocyanine, porphyrin, crown ether, phthalocyanine derivatives, porphyrin derivatives, and crown ether derivatives.

13. The method according to claim 12, characterized in that The perovskite layer is formed by using a perovskite solution, and the passivation layer is formed by using a passivation solution. At least one of the perovskite solution and the passivation solution contains ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt.

14. The method according to claim 13, characterized in that In the passivation solution, the sum of the concentrations of the phthalocyanine, the porphyrin, the crown ether, the phthalocyanine derivatives, the porphyrin derivatives, and the crown ether derivatives is 0.1 mg / mL-8 mg / mL.

15. The method according to claim 13 or 14, characterized in that The ratio of the total molar concentration of the ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt in the perovskite solution to the molar concentration of the perovskite in the perovskite solution is 0.02%-1.2%.

16. The method according to any one of claims 13 to 15, characterized in that The ratio of the total molar concentration of the ethylenediaminetetraacetic acid and / or ethylenediaminetetraacetic acid salt in the passivation solution to the molar concentration of the perovskite in the perovskite solution is 0.02%-2%.

17. An electrical device, characterized in that: include: A perovskite solar cell according to any one of claims 1 to 11, or a perovskite solar cell made by the method according to any one of claims 12 to 16.

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