MOF and manufacturing method thereof, solar cell and manufacturing method thereof, power generation device and power utilization device

Abstract

The invention provides a metal organic framework compound and a preparation method thereof, a perovskite solar cell and a preparation method thereof, a power generation device and a power utilization device. The repeating unit of the metal organic framework compound is represented by the following formula (I). M represents a metal center and comprises at least one of Pb, Sn, Ni, Mn, Co, Cu, Zn and Cr; x comprises halogen; l represents an organic ligand comprising at least one of deprotonated compounds represented by formula (II) or formula (III). In the formula (II) and the formula (III), R1 and R2 respectively and independently comprise at least one of substituted or unsubstituted six-membered to fourteen-membered arylene and substituted or unsubstituted C1-C5 alkylene; r comprises at least one of H and C1-C6 alkyl groups. [(M2X3) (L) 2]. [(R) 2NH2] 3 (I) HOOC-R1-COOH (II) # imgabs0 #

Description

Technical Field

[0001] The present application relates to the field of solar cells, and particularly to a metal-organic framework compound, a preparation method thereof, a perovskite solar cell, a preparation method thereof, a power generation device, and an electric device. Background Art

[0002] With the development of modern industry, the problems of global energy shortage and environmental pollution have become increasingly prominent. As an ideal renewable energy source, solar energy has received more and more attention. A solar cell, also known as a photovoltaic cell, is a device that directly converts light energy into electrical energy through the photovoltaic effect or the photochemical effect. A perovskite solar cell is a solar cell that uses a perovskite-type organometallic halide semiconductor as a light-absorbing material. Perovskite solar cells have attracted much attention due to their advantages such as simple manufacturing process, low production cost, and material cost.

[0003] However, in related technologies, perovskite solar cells have poor stability and low optoelectronic performance, which hinder their practical application and industrial development. Therefore, how to improve the stability and optoelectronic performance of perovskite solar cells remains a technical problem to be solved urgently. Summary of the Invention

[0004] The present application is made in view of the above problems, and its purpose is to provide a metal-organic framework (MOF) compound, a preparation method thereof, a perovskite solar cell, a preparation method thereof, a power generation device, and an electric device. The metal-organic framework compound can absorb ultraviolet light bands that cause perovskite self-degradation, and at the same time emit visible light bands or even near-infrared light bands that can increase the current upper limit after perovskite absorption, thereby improving the stability of perovskite while enhancing the optoelectronic performance of perovskite solar cells.

[0005] To achieve the above purpose, a first aspect of the present application provides a metal-organic framework compound, and the repeating unit of the metal-organic framework compound is represented by the following formula (I):

[0006] [(M2X3)(L)2]·[(R)2NH2]3(I)

[0007] Wherein, M represents a metal center, including at least one of Pb, Sn, Ni, Mn, Co, Cu, Zn, and Cr;

[0008] X includes halogens;

[0009] L represents an organic ligand, including at least one of the compounds represented by deprotonated formula (II) or formula (III):

[0010]

[0011] In the formula (II) and the formula (III), each of R1 and R2 independently includes at least one of a substituted or unsubstituted six- to fourteen-membered arylene group and a substituted or unsubstituted C1-C5 alkylene group;

[0012] R includes at least one of H and C1-C6 alkyl groups.

[0013] The above metal-organic framework compound can absorb the ultraviolet light band that causes perovskite self-degradation, and simultaneously emit visible light bands or even near-infrared light bands that can increase the upper limit of the current after perovskite absorption. Therefore, applying the above MOF compound to a perovskite solar cell can improve the perovskite stability and enhance the optoelectronic performance of the perovskite solar cell at the same time.

[0014] In some embodiments, when the six- to fourteen-membered arylene group or C1-C5 alkylene group is substituted, the substituent includes at least one of a hydroxyl group, a carboxyl group, an amide group, an amino group, an aldehyde group, and a mercapto group.

[0015] By including the above hydrophilic groups such as hydroxyl group, carboxyl group, amide group, amino group, aldehyde group or mercapto group in the MOF compound, setting the MOF compound of the embodiment of the present application between the hole transport layer containing metal oxide and the perovskite layer interface can effectively alleviate the degradation reaction that is prone to occur between the metal oxide and the perovskite layer interface.

[0016] In some embodiments, in the formula (II) and the formula (III), each of R1 and R2 independently includes at least one of an unsubstituted six- to fourteen-membered arylene group and an unsubstituted C1-C5 alkylene group.

[0017] By selecting the above groups, the perovskite stability can be further improved, and the optoelectronic performance of the perovskite solar cell can be enhanced at the same time.

[0018] In some embodiments, the organic ligand includes a deprotonated compound of the formula (II).

[0019] In some embodiments, the organic ligand includes a deprotonated compound of the formula (II), and R1 in the formula (II) includes a phenylene group.

[0020] Therefore, the perovskite stability can be further improved, and the optoelectronic performance of the perovskite solar cell can be enhanced at the same time.

[0021] In some embodiments, M includes at least one of Pb, Sn, and Ni. Therefore, the perovskite stability can be further improved, and the optoelectronic performance of the perovskite solar cell can be enhanced at the same time.

[0022] In some embodiments, the halogen includes at least one of F, Cl, Br, and I. Thereby, the perovskite stability can be further improved while enhancing the optoelectronic performance of the perovskite solar cell.

[0023] In some embodiments, R includes at least one of H and C1-C3 alkyl. Thereby, the perovskite stability can be further improved while enhancing the optoelectronic performance of the perovskite solar cell.

[0024] In some embodiments, the repeating unit is represented as [(Pb2Cl3)(TA)2]·[(CH3)2NH2]3, [(Pb2Br3)(TA)2]·[(CH3)2NH2]3, or [(Pb2I3)(TA)2]·[(CH3)2NH2]3, where TA represents deprotonated terephthalic acid. Thereby, the perovskite stability can be further improved while enhancing the optoelectronic performance of the perovskite solar cell.

[0025] In some embodiments, the metal-organic framework compound has an ultraviolet absorption band in the range of 200 nm to 400 nm and a fluorescence emission band in the range of 400 nm to 1000 nm. Thus, the above metal-organic framework compound can absorb the ultraviolet light band that causes perovskite self-degradation while emitting a visible light band or even a near-infrared light band that can increase the current upper limit after being absorbed by the perovskite. Thereby, applying the above MOF compound to a perovskite solar cell can improve the perovskite stability while enhancing the optoelectronic performance of the perovskite solar cell.

[0026] The second aspect of the present application provides a perovskite solar cell, and the perovskite solar cell includes the metal-organic framework compound of the first aspect of the present application.

[0027] By including the metal-organic framework compound of the first aspect of the present application, the perovskite solar cell according to the embodiments of the present application has an increased current upper limit and enhanced optoelectronic performance.

[0028] In some embodiments, the perovskite solar cell includes a functional layer, and the functional layer includes the metal-organic framework compound. Through this functional layer, the current upper limit and optoelectronic performance of the perovskite solar cell can be increased.

[0029] In some embodiments, the thickness of the functional layer is 1 nm to 80 nm. Controlling the thickness of the functional layer within the above range is beneficial for the functional layer to improve the optoelectronic performance of the perovskite solar cell without having an adverse effect on other properties.

[0030] In some embodiments, the perovskite solar cell further includes a perovskite layer, wherein the functional layer is disposed on the light-incident side of the perovskite layer. Thus, before the incident light reaches the perovskite layer, the ultraviolet light band in the incident light that causes self-degradation of the perovskite has been absorbed by the functional layer, and these lights are converted into visible light or even near-infrared light bands that can increase the upper limit of the current after being absorbed by the perovskite, thereby improving the stability of the perovskite layer and enhancing the optoelectronic performance of the perovskite solar cell.

[0031] In some embodiments, a first charge transport layer and a first electrode are sequentially disposed on the light-incident side of the perovskite layer from near to far, and a second charge transport layer and a second electrode are sequentially disposed on the light-emitting side of the perovskite layer from near to far; the functional layer is disposed at at least one of the following positions: between the perovskite layer and the first charge transport layer, between the first charge transport layer and the first electrode, or on a side of the first electrode facing away from the first charge transport layer. Thus, before the incident light reaches the perovskite layer, the ultraviolet light band in the incident light that causes self-degradation of the perovskite has been absorbed by the functional layer, and these lights are converted into visible light or even near-infrared light bands that can increase the upper limit of the current after being absorbed by the perovskite, thereby improving the stability of the perovskite layer and enhancing the optoelectronic performance of the perovskite solar cell.

[0032] In some embodiments, the perovskite solar cell has one or more of the following characteristics:

[0033] The first electrode is a transparent electrode;

[0034] The second electrode is a back electrode;

[0035] The first charge transport layer is an electron transport layer or a hole transport layer; or

[0036] The second charge transport layer is an electron transport layer or a hole transport layer, but is different from the first charge transport layer.

[0037] The third aspect of the present application provides a method for preparing the metal-organic framework compound of the first aspect of the present application, the method comprising:

[0038] Mixing at least one of the compounds represented by the formula (II) or the formula (III) with a halide of M in a solvent to obtain a precursor solution, the solvent including the compound represented by the formula (IV), wherein R and R4 each independently include at least one of H and C1-C6 alkyl;

[0039]

[0040] Heating the precursor solution in a sealed container; and

[0041] Cool the heated precursor solution to obtain the metal-organic framework compound.

[0042] The metal-organic framework compound obtained thereby can absorb the ultraviolet light band that causes perovskite self-degradation, and at the same time emit visible light bands or even near-infrared light bands that can increase the current limit after perovskite absorption. Thus, applying the above MOF compound to a perovskite solar cell can improve the perovskite stability and enhance the optoelectronic performance of the perovskite solar cell.

[0043] In some embodiments, in formula (IV), R and R4 each independently include at least one of H and C1-C3 alkyl.

[0044] In some embodiments, the molar ratio between at least one of the compounds represented by formula (II) or formula (III) and the halide of M is 1:4 to 4:1.

[0045] In some embodiments, the halide of M includes at least one of fluoride, chloride, bromide, and iodide of M.

[0046] In some embodiments, the method includes: mixing the compound represented by formula (II) and the halide of Pb in a solvent including N,N-dimethylacetamide to obtain a precursor solution.

[0047] The metal-organic framework compound obtained thereby can further improve the perovskite stability and enhance the optoelectronic performance of the perovskite solar cell.

[0048] The fourth aspect of the present application provides a method for preparing a perovskite solar cell, the method including:

[0049] Providing a first electrode; and

[0050] Successively forming a first charge transport layer, a perovskite layer, a second charge transport layer, and a second electrode on the first electrode,

[0051] Wherein, the step of successively forming a first charge transport layer, a perovskite layer, a second charge transport layer, and a second electrode on the first electrode includes:

[0052] Forming a functional layer on the light-incident side of the perovskite layer, the functional layer including the metal-organic framework compound of the first aspect of the present application.

[0053] By forming a functional layer containing a metal-organic framework compound, the perovskite solar cell in the embodiments of the present application has an increased current limit and enhanced optoelectronic performance.

[0054] In some embodiments, the first electrode is a transparent electrode and the second electrode is a back electrode. The steps of sequentially forming a first charge transport layer, a perovskite layer, a second charge transport layer, and a second electrode on the first electrode include:

[0055] Form a functional layer at at least one of the following positions: on a side of the first electrode facing away from the first charge transport layer, between the first electrode and the first charge transport layer, and between the first charge transport layer and the perovskite layer.

[0056] The fifth aspect of the present application provides a power generation device, which includes the perovskite solar cell of the second aspect of the present application or the perovskite solar cell prepared by the method of the fourth aspect of the present application.

[0057] The sixth aspect of the present application provides an electrical device, which includes the perovskite solar cell of the second aspect of the present application or the perovskite solar cell prepared by the method of the fourth aspect of the present application.

[0058] The present application provides a metal-organic framework compound and a preparation method thereof. The metal-organic framework compound can absorb ultraviolet light bands that cause self-degradation of perovskite, and at the same time emit visible light bands or even near-infrared light bands that can increase the current upper limit after perovskite absorption, thereby enhancing the photoelectric performance of perovskite solar cells while improving the stability of perovskite.

[0059] The present application also provides a perovskite solar cell including the metal-organic framework compound and a preparation method thereof, as well as a power generation device or an electrical device including the perovskite solar cell. The perovskite solar cell, power generation device or electrical device has corresponding technical advantages brought by the metal-organic framework compound. Description of the Drawings

[0060] Figure 1 Shows a schematic structural diagram of a perovskite solar cell module according to an embodiment of the present application.

[0061] Figure 2 Shows powder X-ray diffraction patterns of MOF compounds PX1, PX2, and PX3 prepared in Preparation Examples 1 to 3 of the present application.

[0062] Figure 3 Shows the ultraviolet absorption and fluorescence emission spectra of the MOF compound PX1 prepared in Preparation Example 1 of the present application and the CIE chromaticity coordinate diagram of the fluorescence emission.

[0063] Figure 4 Shows the ultraviolet absorption and fluorescence emission spectra of the MOF compound PX2 prepared in Preparation Example 2 of the present application and the CIE chromaticity coordinate diagram of the fluorescence emission.

[0064] Figure 5 Shows the UV absorption and fluorescence emission spectra of the MOF compound PX3 prepared in Preparation Example 3 of the present application, as well as the CIE chromaticity coordinate diagram of the fluorescence emission.

[0065] Figure 6 Shows the schematic structural diagrams of the MOF compounds PX1, PX2, and PX3 prepared in Preparation Examples 1 to 3 of the present application.

[0066] Explanation of reference numerals:

[0067] 1: transparent electrode; 2: first charge transport layer; 3: functional layer; 4: perovskite layer; 5: second charge transport layer; 6: back electrode. Detailed implementation manners

[0068] Hereinafter, embodiments of the metal-organic framework compound, its preparation method, perovskite solar cell, its preparation method, power generation device, and power consumption device of the present application are specifically disclosed with appropriate reference to the drawings. However, there may be cases where unnecessary detailed descriptions are omitted. For example, there may be cases where detailed descriptions of well-known matters and repeated descriptions of actually identical structures are omitted. This is to avoid the following description from becoming unnecessarily lengthy and to facilitate the understanding of those skilled in the art. In addition, the drawings and the following description are provided for those skilled in the art to fully understand the present application and are not intended to limit the subject matter recited in the claims.

[0069] The "range" disclosed in the present application is defined in the form of a lower limit and an upper limit. A given range is defined by selecting a lower limit and an upper limit, and the selected lower limit and upper limit define the boundary of a particular range. The ranges defined in this way can include or exclude the end values and can be combined arbitrarily, that is, any lower limit can be combined with any upper limit to form a range. For example, if ranges of 60 - 120 and 80 - 110 are listed for a specific parameter, ranges of 60 - 110 and 80 - 120 are also contemplated. In addition, if the minimum range values 1 and 2 are listed, and if the maximum range values 3, 4, and 5 are listed, then the following ranges are all contemplated: 1 - 3, 1 - 4, 1 - 5, 2 - 3, 2 - 4, and 2 - 5. In the present application, unless otherwise stated, the numerical range "a - b" represents an abbreviated representation of any real number combination between a and b, where a and b are both real numbers. For example, the numerical range "0 - 5" represents that all real numbers between "0 - 5" have been fully listed herein, and "0 - 5" is only an abbreviated representation of these numerical combinations. Additionally, when stating that a certain parameter is an integer ≥2, it is equivalent to disclosing that the parameter is, for example, the integer 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0070] Unless otherwise specified, all embodiments and optional embodiments of the present application can be combined with each other to form new technical solutions.

[0071] Unless otherwise specified, all technical features and optional technical features of the present application can be combined with each other to form new technical solutions.

[0072] Unless otherwise specified, all steps of the present application can be carried out in sequence or randomly, preferably in sequence. For example, the method includes steps (a) and (b), which means that the method may include steps (a) and (b) carried out in sequence, or may also include steps (b) and (a) carried out in sequence. For example, it is mentioned that the method may further include step (c), which means that step (c) can be added to the method in any order. For example, the method may include steps (a), (b) and (c), or may also include steps (a), (c) and (b), or may also include steps (c), (a) and (b), etc.

[0073] Unless otherwise specified, when an element or layer is described as "between... and...", "on...", "adjacent to...", "connected to...", "coupled to..." other elements or layers, it can be between other elements or layers, on other elements or layers, adjacent to other elements or layers, connected or coupled to other elements or layers in a directly contacting manner, or can be in a non-directly contacting manner, that is, there are intermediate elements or layers. On the contrary, when an element or layer is described as "directly between... and...", "directly on...", "directly adjacent to...", "directly connected to..." or "directly coupled to..." other elements or layers, there are no intermediate elements or layers.

[0074] Unless otherwise specified, the terms used in the present application have the well-known meanings commonly understood by those skilled in the art.

[0075] Unless otherwise specified, the numerical values of the various parameters mentioned in the present application can be determined by various common testing methods in the art. For example, they can be determined according to the testing methods given in the present application.

[0076] Definition

[0077] The term "arylene" refers to a group formed by an aromatic hydrocarbon losing two hydrogen atoms. In this article, typical arylene groups contain 6 to 14 (such as 6, 7, 8, 9, 10, 11, 12, 13, 14) carbon atoms on the aromatic ring. For example, it can include phenylene, naphthylene, anthrylene or biphenylene, etc., but is not limited thereto.

[0078] The term "phenylene" can include, for example, 1,2-phenylene, 1,3-phenylene or 1,4-phenylene, etc., but is not limited thereto.

[0079] The term "naphthylene" may include, for example, 1,3-naphthylene, 1,4-naphthylene, 1,5-naphthylene, 1,6-naphthylene, 1,7-naphthylene, 1,8-naphthylene, 2,3-naphthylene, 2,4-naphthylene, 2,5-naphthylene, 2,6-naphthylene, 2,7-naphthylene or 2,8-naphthylene, etc., but is not limited thereto.

[0080] The term "anthrylene" may include, for example, 1,8-anthrylene, 2,3-anthrylene or 9,10-anthrylene, etc., but is not limited thereto.

[0081] The term "biphenylene" may include, for example, 2,2'-biphenylene, 3,3'-biphenylene, 4,4'-biphenylene or 1,1'-biphenyl-2,5-ylidene, etc., but is not limited thereto.

[0082] The term "alkyl" refers to a hydrocarbon group formed by removing one hydrogen atom from an alkane molecule, which can be straight-chain or branched-chain and is connected to other parts of the molecule by a single bond. The alkyl group used herein usually contains 1 to 20 (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20) carbon atoms, optionally containing 1 to 6 carbon atoms (i.e., C1-C6 alkyl). Optional C1-C6 alkyl includes C1-C5 alkyl, C1-C4 alkyl, C1-C3 alkyl, C1-C2 alkyl or C1 alkyl. Examples of C1-C6 alkyl include, but are not limited to, methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, n-pentyl, sec-pentyl, hexyl.

[0083] The term "alkylene" refers to a hydrocarbon group formed by removing two hydrogen atoms from an alkane molecule (divalent alkyl), which can be straight-chain or branched-chain and is connected to other parts of the molecule by a single bond. Typically, the alkylene group herein contains 1 to 10 (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, 10) carbon atoms, optionally containing 1 to 5 carbon atoms (i.e., C1-C5 alkylene). Examples of alkylene may include methylene, ethylene, n-propylene, isopropylene, n-butylene, isobutylene, tert-butylene, sec-butylene, n-pentylene, 1-methylbutylene, 2-methylbutylene, 3-methylbutylene, isopentylene, 1-ethylpropylene, neopentylene, etc.

[0084] A solar cell, also known as a photovoltaic cell, is a device that directly converts light energy into electrical energy through the photovoltaic effect or the photochemical effect. A perovskite solar cell is a solar cell that uses a perovskite-type organometallic halide semiconductor as a light-absorbing material. Perovskite solar cells have attracted much attention due to advantages such as simple manufacturing processes, low production costs, and material costs.

[0085] However, on the one hand, perovskite is prone to absorb ultraviolet light and cause self-degradation, which has an adverse effect on the stability of perovskite solar cells, resulting in poor stability and shortened lifespan of perovskite solar cells. On the other hand, when incident light passes through the transparent conducting oxide (TCO) glass / charge transport layer, affected by the transmittance, not all of it can be incident on the perovskite layer, which limits the current upper limit and the photoelectric conversion efficiency of perovskite solar cells.

[0086] Based on this, the present application proposes a metal-organic framework compound and its preparation method, a perovskite solar cell and its preparation method, a power generation device, and an electrical device.

[0087] Metal-organic framework compound

[0088] In the first aspect of the present application, a metal-organic framework compound is provided. The repeating unit of the metal-organic framework compound is represented by the following formula (I):

[0089] [(M2X3)(L)2]·[(R)2NH2]3 (I)

[0090] Wherein, M represents a metal center, including at least one of Pb, Sn, Ni, Mn, Co, Cu, Zn, and Cr.

[0091] X includes halogens.

[0092] L represents an organic ligand, including at least one of the compounds represented by deprotonated formula (II) or formula (III):

[0093]

[0094] In formula (II) and formula (III), R1 independently includes at least one of a substituted or unsubstituted six- to fourteen-membered arylene group and a substituted or unsubstituted C1-C5 alkylene group.

[0095] R includes at least one of H and C1-C6 alkyl groups.

[0096] The metal-organic framework compound is a periodic complex repeatedly composed of the repeating unit [(M2X3)(L)2]·[(R)2NH2]3.

[0097] Taking the compound of formula (II) with deprotonated organic ligand L as an example, the structure of the asymmetric repeating unit can be schematically represented by the following chemical formula (V):

[0098]

[0099] In chemical formula (V), L represents an organic ligand, R3 represents [(R)2NH2], O represents an oxygen atom, M represents a metal center, and X represents a halogen.

[0100] The solid line of M-O: represents the coordination of a metal atom and an oxygen atom within an asymmetric repeating unit.

[0101] The solid line of M-X: represents the coordination of a metal atom and a halogen atom within an asymmetric repeating unit.

[0102] The dashed line of R3-O: represents the formation of a hydrogen bond between an amine cation and an oxygen atom.

[0103] The dashed line of M-O: represents the coordination of a metal atom of one asymmetric repeating unit and an oxygen atom of another asymmetric repeating unit.

[0104] Although the mechanism is not yet clear, the metal-organic framework compound has a three-dimensional network structure of cation-anion counterbalance, which can be divided into an anion part [(M2X3)(L)2] and a cation part [(R)2NH2]. The anion part is the main part of the compound, mainly composed of a three-dimensional anion framework formed by the coordination of metal halides and organic ligands. With metal atoms as network nodes and halogen atoms and oxygen atoms of organic ligands as bridges, a negatively charged three-dimensional network anion framework structure with nanoscale size is formed. The cation part [(R)2NH2] is a small organic amine molecule with a positive charge, such as a dimethylamine cation ( + ).

[0105] Due to the special coordination structure as described above, the metal-organic framework compound has the tuning function of absorbing light in the ultraviolet light band and emitting light in the visible light band or even in the near-infrared light band.

[0106] The perovskite in a perovskite solar cell is prone to absorb ultraviolet light and cause self-degradation, resulting in poor stability and shortened battery life of the perovskite solar cell. Before the incident light irradiates the perovskite layer of the perovskite solar cell, the incident light is first irradiated through a functional layer including the above metal-organic framework compound. The MOF compound can absorb the ultraviolet light in the incident light that causes self-degradation of the perovskite layer. At the same time, the above MOF compound has no obvious absorption of visible light, which is beneficial to the visible light in the incident light irradiating on the perovskite layer and being absorbed by it, thereby increasing the upper limit of the current.

[0107] In related technologies, after the incident light irradiated on a perovskite solar cell passes through a TCO (Transparent Conducting Oxide) glass / charge transport layer, affected by the transmittance, not all of it can be incident on the perovskite layer, which limits the upper limit of the current of the perovskite solar cell. To address this issue, the MOF compound in this paper can emit fluorescence in the visible light band or even the near-infrared light band after absorbing ultraviolet light. In this way, the incident light on the perovskite layer in the perovskite solar cell and the fluorescence emitted by the MOF compound are superimposed and absorbed by the perovskite layer, increasing the light absorption amount of the perovskite layer, thereby increasing the upper limit of the current of the perovskite solar cell and enhancing its optoelectronic performance.

[0108] Therefore, the organic framework compound of the embodiment of the present application can absorb the ultraviolet light band that causes self-degradation of the perovskite layer and convert this light into visible light or even near-infrared light that can increase the upper limit of the current after being absorbed by the perovskite. Thereby, the upper limit of the current of the perovskite solar cell can be increased, and its optoelectronic performance can be enhanced.

[0109] In some embodiments, when the six- to fourteen-membered arylene or C1-C5 alkylene group is substituted, the substituents include at least one of a hydroxyl group (-OH), a carboxyl group (-COOH), an amide group (-C(O)NH2), an amino group (-NH2), an aldehyde group (-CHO), and a mercapto group (-SH).

[0110] In a common inverted perovskite solar cell, a metal oxide, such as NiOx, is usually used as the hole transport layer. However, a metal oxide, such as NiOx, is prone to degradation reaction with the perovskite layer interface. Setting the MOF compound of the embodiment of the present application between the metal oxide and the perovskite layer interface can effectively alleviate this degradation reaction. The carboxyl group (-COOH) and / or phosphoric acid group (-P(O)(OH)2) in the MOF compound have a passivation function on the metal oxide in the hole transport layer, preventing the metal oxide from degrading the perovskite interface. For the MOF compound in which the organic ligand further contains hydrophilic groups such as hydroxyl, carboxyl, amide, amino, aldehyde, or mercapto groups, these hydrophilic groups help to form an organic hydrophilic layer and promote perovskite crystallization.

[0111] Thus, in an inverted perovskite solar cell with a metal oxide, such as NiOx, as the hole transport layer, the above-mentioned organic framework compound can prevent the metal oxide from degrading the perovskite interface and / or promote perovskite crystallization.

[0112] In some embodiments, in Formula (II) and Formula (III), each of R1 and R2 independently includes at least one of an unsubstituted six-membered to fourteen-membered arylene or an unsubstituted C1-C5 alkylene; optionally, each of R1 and R2 independently includes at least one of phenylene, naphthylene, anthrylene, biphenylene, methylene, ethylene, propylene, butylene or pentylene.

[0113] "Phenylene" can include, for example, 1,2-phenylene, 1,3-phenylene or 1,4-phenylene.

[0114] "Naphthylene" can include, for example, 1,3-naphthylene, 1,4-naphthylene, 1,5-naphthylene, 1,6-naphthylene, 1,7-naphthylene, 1,8-naphthylene, 2,3-naphthylene, 2,4-naphthylene, 2,5-naphthylene, 2,6-naphthylene, 2,7-naphthylene or 2,8-naphthylene, etc., but is not limited thereto.

[0115] "Anthrylene" can include, for example, 1,8-anthrylene, 2,3-anthrylene or 9,10-anthrylene, etc., but is not limited thereto.

[0116] "Biphenylene" can include, for example, 2,2'-biphenylene, 3,3'-biphenylene, 4,4'-biphenylene or 1,1'-biphenyl-2,5-ylidene, etc., but is not limited thereto.

[0117] The "C1-C5 alkylene" can be straight-chain or branched. The C1-C5 alkylene can include, for example, at least one of methylene, ethylene, propylene, butylene or pentylene; optionally, it can include at least one of methylene, ethylene, n-propylene, isopropyl, n-butyl, isobutyl, tert-butyl, sec-butyl, n-pentyl, 1-methylbutylene, 2-methylbutylene, 3-methylbutylene, isopentylene, 1-ethylpropylene, neopentylene.

[0118] By selecting the above groups, the upper limit of the current of the perovskite solar cell can be further increased, and its optoelectronic performance can be enhanced.

[0119] In some embodiments, the organic ligand includes a deprotonated compound of Formula (II). In some embodiments, R1 in Formula (II) includes phenylene.

[0120] As described above, phenylene can include 1,2-phenylene, 1,3-phenylene or 1,4-phenylene. Optionally, phenylene can include 1,4-phenylene.

[0121] In some embodiments, M can include at least one of Pb, Sn, Ni. In some embodiments, M can include Pb.

[0122] In some embodiments, the halogen includes at least one of F, Cl, Br, and I. In some embodiments, the halogen includes at least one of Cl, Br, and I.

[0123] In some embodiments, R may include at least one of H, C1-C3 alkyl. In some embodiments, R may include at least one of H, methyl, or ethyl. In some embodiments, R may include at least one of H, methyl. In some embodiments, R may include methyl.

[0124] In some embodiments, the repeating unit can be represented as [(Pb2Cl3)(TA)2]·[(CH3)2NH2]3, [(Pb2Br3)(TA)2]·[(CH3)2NH2]3, or [(Pb2I3)(TA)2]·[(CH3)2NH2]3. Wherein, TA represents deprotonated terephthalic acid.

[0125] In some embodiments, the metal-organic framework compound has an ultraviolet absorption band in the range of 200 nm to 400 nm and a fluorescence emission band in the range of 400 nm to 1000 nm. In some embodiments, the metal-organic framework compound has an ultraviolet absorption band in the range of 200 nm to 400 nm and a fluorescence emission band in the range of 400 nm to 700 nm.

[0126] In the spectral energy, the short-wavelength light energy is greater than the long-wavelength light energy. Usually, a luminescent compound emits long-wavelength light after absorbing short-wavelength light. The MOF compounds herein are a class of compounds that can absorb light with wavelengths in the range of 200 nm to 400 nm and emit light with wavelengths in the range of 400 nm to 1000 nm. Through this property, this type of compound can absorb the ultraviolet light band that causes perovskite self-degradation, and at the same time emit visible light bands or even near-infrared light bands that can increase the current limit after perovskite absorption. Thereby, the self-degradation of perovskite caused by absorbing ultraviolet light is inhibited, and the light absorption amount of perovskite for visible light is increased, so that the current limit of the solar cell can be increased and its optoelectronic performance can be enhanced.

[0127] Perovskite solar cell

[0128] The second aspect of the present application provides a perovskite solar cell. The perovskite solar cell includes the metal-organic framework compound of the first aspect of the present application.

[0129] As described above, the metal-organic framework compound of the first aspect of the present application can absorb the ultraviolet light band that causes perovskite self-degradation, and at the same time emit visible light bands and even near-infrared light bands that can be absorbed by perovskite. This compound can convert the ultraviolet light band that causes perovskite self-degradation into fluorescence in the visible light and even near-infrared light bands that can increase the current limit after being absorbed by perovskite. In this way, the incident light on the perovskite layer in the perovskite solar cell and the fluorescence emitted by the MOF compound are superimposed and absorbed by the perovskite layer, increasing the light absorption amount of the perovskite layer, thereby increasing the current limit of the perovskite solar cell and enhancing its optoelectronic performance.

[0130] Therefore, by including the metal-organic framework compound of the first aspect of the present application, the perovskite solar cell of the embodiment of the present application has an increased current limit and enhanced optoelectronic performance.

[0131] In some embodiments, the perovskite solar cell includes a functional layer, and the functional layer includes the metal-organic framework compound. The functional layer is at least used to enhance the optoelectronic performance of the perovskite solar cell.

[0132] The functional layer refers to a functional layer disposed in the perovskite solar cell that can at least increase at least one of the open-circuit voltage Voc, short-circuit current density Jsc, fill factor FF, photoelectric conversion efficiency, and perovskite layer stability of the perovskite solar cell. Herein, the metal-organic framework compound can be disposed in the perovskite solar cell in the form of a functional layer, for example. Thus, the metal-organic framework compound can be conveniently disposed in the perovskite solar cell by means of spin coating, slot coating, roll coating, blade coating, screen printing, etc.

[0133] In some embodiments, the thickness of the functional layer can be 1 nm to 80 nm. In some embodiments, the thickness of the functional layer can be 2 nm to 30 nm. In some embodiments, the thickness of the functional layer can be 2 nm to 20 nm. For example, the thickness of the functional layer can be 1 nm, 2 nm, 3 nm, 5 nm, 10 nm, 15 nm, 20 nm, 25 nm, 30 nm, 35 nm, 40 nm, 45 nm, 50 nm, 55 nm, 60 nm, 65 nm, 70 nm, 75 nm or 80 nm, but not limited thereto.

[0134] The thickness of the functional layer refers to the dimension of the functional layer in the thickness direction of the perovskite solar cell. The thickness direction of the perovskite solar cell refers to the direction in which the layers are stacked in sequence. The thickness of the layer can be easily measured, for example, by observing with a microscope, such as observing the cross-section of the layer with an electron microscope, or by surface profilometry using, for example, a stylus profilometer.

[0135] Controlling the thickness of the functional layer within the above range is beneficial for the functional layer to enhance the photoelectric performance of the perovskite solar cell without adversely affecting other performances.

[0136] In some embodiments, the perovskite solar cell further includes a perovskite layer, wherein the functional layer is disposed on a light incident side of the perovskite layer.

[0137] The light incident side of the perovskite layer refers to the side from which the incident light enters the perovskite layer. By arranging the functional layer on the light incident side of the perovskite layer, before the incident light reaches the perovskite layer, the ultraviolet light band in the incident light that causes the self-degradation of the perovskite has been absorbed by the functional layer, and these lights are converted into visible light or even near-infrared light bands that can increase the upper limit of the current after absorption by the perovskite. Here, the functional layer can be arranged to be in direct contact with the perovskite layer or not. That is to say, other functional layers can be arranged between the functional layer and the perovskite layer or no other functional layers can be arranged.

[0138] In some embodiments, a first charge transport layer and a first electrode are sequentially arranged on the light-incident side of the perovskite layer from near to far, and a second charge transport layer and a second electrode are sequentially arranged on the backlight side of the perovskite layer from near to far. The functional layer is arranged at at least one of the following positions: between the perovskite layer and the first charge transport layer, between the first charge transport layer and the first electrode, or on the side of the first electrode facing away from the first charge transport layer.

[0139] The backlight side of the perovskite layer refers to the side opposite to the light-entering side of the perovskite layer. The near and far in the expression "from near to far" refer to the distance relative to the perovskite layer. Then, a first charge transport layer and a first electrode are sequentially arranged from near to far on the light-entering side of the perovskite layer, which means that the arrangement order along the incident direction of the incident light on the light-entering side of the perovskite layer is the first electrode, the first charge transport layer and the perovskite layer. Other functional layers may or may not be arranged between the perovskite layer and the first charge transport layer or between the first charge transport layer and the first electrode. Similarly, a second charge transport layer and a second electrode are sequentially arranged from near to far on the backlight side of the perovskite layer, which means that the arrangement order along the incident direction of the incident light on the backlight side of the perovskite layer is the perovskite layer, the second charge transport layer and the second electrode. Other functional layers may or may not be arranged between the perovskite layer and the second charge transport layer or between the second charge transport layer and the second electrode.

[0140] The functional layer is disposed at at least one of the following positions: between the perovskite layer and the first charge transport layer, between the first charge transport layer and the first electrode, or on a side of the first electrode facing away from the first charge transport layer. By disposing the functional layer at at least one of the above positions, before the incident light irradiates the perovskite layer of the perovskite solar cell, the incident light first irradiates and passes through the functional layer including the metal-organic framework compound, and then irradiates onto the perovskite layer. When the incident light irradiates and passes through the functional layer, the metal-organic framework compound in the functional layer absorbs the ultraviolet light that causes self-degradation of the perovskite, and simultaneously emits visible light that can be absorbed by the perovskite, thereby increasing the light absorption amount of the perovskite layer, and further increasing the upper limit of the current of the solar cell and enhancing its optoelectronic performance.

[0141] In some embodiments, the first electrode is a transparent electrode and the second electrode is a back electrode. Figure 1 The structural schematic diagram of a perovskite solar cell module according to an embodiment of the present application is shown. As Figure 1 shown, the perovskite solar cell has a layered structure, which sequentially includes a transparent electrode 1, a first charge transport layer 2, a functional layer 3, a perovskite layer 4, a second charge transport layer 5, and a back electrode 6. The first charge transport layer 2 may be an electron transport layer, and the second charge transport layer 5 may be a hole transport layer; or, the first charge transport layer 2 may be a hole transport layer, and the second charge transport layer 5 may be an electron transport layer. In this embodiment, the functional layer 3 is schematically disposed between the first charge transport layer 2 and the perovskite layer 4. In some embodiments, the functional layer 3 may be disposed between the first charge transport layer 2 and the transparent electrode 1. In some embodiments, the functional layer 3 may be disposed on a side of the transparent electrode 1 facing away from the first charge transport layer. By disposing the functional layer 3 in these ways, the functional layer 3 can absorb the ultraviolet wavelength band in the incident light that causes self-degradation of the perovskite, and emit the visible wavelength band or even the near-infrared wavelength band that can increase the upper limit of the current after being absorbed by the perovskite. Thus, on the one hand, the stability of the perovskite layer is improved, and on the other hand, the light absorption amount of the perovskite layer is increased, and further the optoelectronic performance of the perovskite solar cell is enhanced.

[0142] In some embodiments, the first charge transport layer is an electron transport layer or a hole transport layer; or the second charge transport layer is an electron transport layer or a hole transport layer, but is different from the first charge transport layer.

[0143] In some embodiments, one of the first charge transport layer and the second charge transport layer is a hole transport layer. The hole transport layer is responsible for transporting holes and blocking electrons. The hole transport layer may include one or more of the following materials and their derivatives, but is not limited thereto: 2,2’,7,7’-tetrakis(N,N-di-p-methoxyaniline)-9,9’-spirobifluorene (Spiro-OMeTAD), methoxytriphenylamine-fluoromethylformamidine (OMeTPA-FA), poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA), 3,4-ethylenedioxythiophene-methoxytriphenylamine (EDOT-OMeTPA), N-(4-aniline)carbazole-spirobifluorene (CzPAF-SBF), polypyrrole (p-PY), bipyridine (PPY2), (4-(3,6-dimethyl-9H-carbazol-9-yl)butyl)phosphonic acid (Me-4PACz), [2-(3,6-dimethoxy-9H-carbazol-9-yl)ethyl]phosphonic acid (MeO-2PACz), poly(3,4-ethylenedioxythiophene):polystyrenesulfonic acid (PEDOT:PSS), poly(3-hexylthiophene) (P3HT), imide compounds, quinone compounds, WO3, thiophene, phthalocyanine, porphyrin, molybdenum oxide, vanadium oxide, tungsten oxide, nickel oxide, copper oxide, tin oxide, molybdenum sulfide, tungsten sulfide, copper sulfide, tin sulfide, cuprous thiocyanate, copper iodide, fluorine-containing phosphonic acid, carbonyl-containing phosphonic acid, carbon nanotubes and graphene.

[0144] In some embodiments, one of the first charge transport layer and the second charge transport layer is an electron transport layer. The electron transport layer is responsible for extracting electrons and blocking holes. The electron transport layer may include one or more of the following materials and their derivatives, but is not limited thereto: fullerenes and their derivatives (such as [6,6]-phenyl-C 61 -isobutyl methanoate (PC 61 BM), [6,6]-phenyl-C 71 -methyl butyrate (PC 71 BM), fullerene C 60 、fullerene C 70 、cyano-containing polyphenylacetylene, boron-containing polymers, bathocuproine, bathophenanthroline, tris(8-hydroxyquinoline)aluminum, oxadiazole compounds, benzimidazole compounds, naphthalenetetracarboxylic acid compounds, perylene derivatives, phosphine oxide compounds, phosphine sulfide compounds, fluorine-containing phthalocyanine, titanium oxide, zinc oxide, indium oxide, tin oxide, gallium oxide, tin sulfide, indium sulfide, lithium fluoride, sodium fluoride, magnesium fluoride, calcium fluoride and zinc sulfide.

[0145] In some embodiments, the second electrode may include at least one of a metal conductive material or a conductive oxide, but is not limited thereto. The metal conductive material may include, for example, at least one of Au, Ag, Cu, Al, Ni, Cr, Bi, Pt, Mg, but is not limited thereto. The conductive oxide may include, for example, at least one of fluorine-doped tin oxide (FTO), indium tin oxide (ITO), indium oxide doped with tungsten (IWO), aluminum-doped zinc oxide (AZO), MoO3, but is not limited thereto.

[0146] In some embodiments, the first electrode is similar to the second electrode, except that the first electrode is a transparent electrode for light incidence.

[0147] In some embodiments, the first electrode has a substrate. The substrate may include one or more of glass, PET (polyethylene terephthalate), PI (polyimide), but is not limited thereto.

[0148] In some embodiments, the perovskite layer may include a compound of the general formula ABX3 or A2CDX6, but is not limited thereto. Wherein, A includes inorganic or organic or organo-inorganic hybrid cations, B includes metal cations, and X includes halogens. Exemplarily, A includes organic amine cations, Cs + , K + , Rb + , Li + and at least one of them. Exemplarily, the organic amine cation includes (NR5R6R7R8) + , (R5R6N=CR7R8) + , (R5R6N-C(R9)=NR7R8) + or (R5R6N-C(NR9R 10 )=R7R8) + , wherein, R5, R6, R7, R8, R9 and R 10 each independently include H, substituted or unsubstituted C1-20 alkyl or substituted or unsubstituted aryl. Exemplarily, the organic amine cation includes CH3NH3 + (abbreviated as MA + ), H2N-CH=NH2 + (abbreviated as FA + ), Li + , Na + , K + , Rb + and Cs + and at least one of them. Exemplarily, B includes at least one of lead, tin, zinc, titanium, antimony, bismuth, nickel, iron, cobalt, silver, copper, gallium, germanium, magnesium, calcium, indium, manganese, chromium, molybdenum and europium. C includes inorganic or organic or organo-inorganic hybrid cations. Exemplarily, C includes Ag+ . D includes inorganic or organic or organic-inorganic hybrid cations. Exemplarily, D may include aluminum cation Al 3+ , bismuth cation Bi 3+ , antimony cation Sb 3+ and indium cation In 3+ among others. Exemplarily, X includes F - , Cl - , Br - and I - among others.

[0149] In some embodiments, the perovskite layer may include FA 0.95 Cs 0.05 PbI3, CsPbI3, FA 0.95 Cs 0.05 SnI3, FA 0.95 Cs 0.05 Pb(I 0.9 Br 0.1 )3 among others.

[0150] In some embodiments, the bandgap of the perovskite layer may be 1.20 - 3.10 eV. The bandgap measurement method may include, for example: obtaining an ultraviolet absorption curve through ultraviolet absorption spectroscopy test, and then calculating the perovskite bandgap through the Tauc equation.

[0151] In some embodiments, the thickness of the perovskite layer may be 150 - 1000 nm, such as but not limited to: any value among 150 nm, 200 nm, 300 nm, 400 nm, 500 nm, 600 nm, 700 nm, 800 nm, 900 nm and 1000 nm or the range value between any two of them. The thickness of the perovskite layer refers to the dimension of the perovskite layer in the thickness direction of the perovskite solar cell. The thickness direction of the perovskite solar cell refers to the direction in which each functional layer is stacked in sequence.

[0152] In some embodiments, a passivation layer may be provided between the perovskite layer and the first charge transport layer to passivate the defects at their interface.

[0153] In some embodiments, a passivation layer may be provided between the perovskite layer and the second charge transport layer to passivate the defects at their interface.

[0154] In some embodiments, the perovskite solar cell is a reverse perovskite solar cell. The perovskite solar cell includes a first electrode, and a first charge transport layer, a functional layer, a perovskite layer, a second charge transport layer, and a second electrode sequentially disposed on the first electrode. Among them, the first electrode is a transparent electrode, the second electrode is a back electrode, the first charge transport layer is a hole transport layer, and the hole transport layer includes a metal oxide. The metal oxide includes at least one of nickel oxide, molybdenum oxide, vanadium oxide, tungsten oxide, copper oxide, and tin oxide. The functional layer is directly disposed between the hole transport layer and the perovskite layer.

[0155] In common reverse perovskite solar cells, a metal oxide, such as nickel oxide NiOx, is usually used as the hole transport layer. However, metal oxides, such as NiOx, are prone to degradation reactions with the perovskite interface. According to some embodiments of the present application, a functional layer is disposed between the hole transport layer and the perovskite layer. The functional layer includes the MOF compound of the first aspect of the present application. The carboxyl group and / or phosphate group in the compound has a passivation function on the metal oxide in the hole transport layer, preventing the degradation of the perovskite interface by the metal oxide. For MOF compounds in which the organic ligand further contains hydrophilic groups such as hydroxyl, carboxyl, amide, amino, aldehyde, or mercapto groups, these hydrophilic groups help to form an organic hydrophilic layer and promote perovskite crystallization.

[0156] Method for preparing metal-organic framework compound

[0157] The third aspect of the present application provides a method for preparing the metal-organic framework compound of the first aspect of the present application. The method includes: mixing at least one of the compounds represented by the formula (II) or formula (III) and a halide of M in a solvent to obtain a precursor solution, where the solvent includes the compound represented by the formula (IV), wherein R and R4 each independently include at least one of H and C1-C6 alkyl;

[0158]

[0159] Heating the precursor solution in a closed container; and

[0160] Cooling the heated precursor solution to obtain the metal-organic framework compound.

[0161] The compound of the formula (II) or formula (III) is as follows:

[0162]

[0163] Among them, R1 and R2 are defined as above.

[0164] In the above method, the compound of formula (II) or formula (III) will be used as an organic ligand in the MOF compound. M in the halide of M will be used as a metal center in the MOF compound. The options for M are as described above. The halogen in the halide of M will be used as a halogen in the MOF compound. The N(R)2 moiety in formula (IV) is used to form the [(R)2NH2] moiety in the MOF compound.

[0165] By the above method, the MOF compound of the first aspect of the present application is obtained. The MOF compound can absorb the ultraviolet light band that causes perovskite self-degradation, and at the same time emit visible light bands or even near-infrared light bands that can increase the current upper limit after being absorbed by the perovskite. Thus, while improving the stability of the perovskite, the optoelectronic performance of the perovskite solar cell is enhanced.

[0166] In some embodiments, the molar ratio between the compound of formula (II) or formula (III) and the halide of M can be 1:4 to 4:1, optionally 1:2 to 2:1, but not limited thereto. For example, the molar ratio can be 1:4, 1:3, 1:2, 1:1, 2:1, 3:1 or 4:1, but not limited thereto.

[0167] In some embodiments, the halide of M includes at least one of fluoride, chloride, bromide, and iodide of M; optionally, the halide of M includes at least one of chloride, bromide, and iodide of M.

[0168] In some embodiments, in formula (IV), R and R4 each independently include at least one of H and C1-C3 alkyl; optionally, R and R4 each independently include at least one of H, methyl or ethyl. Optionally, the solvent represented by formula (IV) includes at least one of N,N-dimethylformamide, N,N-dimethylacetamide, formamide or acetamide.

[0169] In some embodiments, in addition to the solvent represented by formula (IV), the solvent may further include other solvents. Other solvents may include, for example, at least one of acetonitrile, N-methylpyrrolidone (NMP), propylenediamine, and pyridine, but not limited thereto. The volume ratio of the solvent represented by formula (IV) to other solvents is not particularly limited, for example, it can be 3:1.

[0170] In some embodiments, relative to 1 mmol of the halide of M, the usage amount of the solvent can be 3 ml to 20 ml, optionally 4 ml to 15 ml, but not limited thereto.

[0171] In some embodiments, the compound of formula (II) and a halide of Pb are mixed in a solvent including N,N-dimethylacetamide to obtain a precursor solution. In some embodiments, R1 in formula (II) includes a phenylene group. In some embodiments, R1 in formula (II) includes a 1,4-phenylene group. In some embodiments, the halide of Pb includes at least one of lead chloride, lead bromide, and lead iodide.

[0172] In some embodiments, terephthalic acid and a halide of Pb are mixed in a solvent including N,N-dimethylacetamide to obtain a precursor solution.

[0173] In some embodiments, the temperature for heating the precursor solution can be 80°C to 200°C, optionally 100°C to 170°C, but not limited thereto. For example, the temperature for heating the precursor solution can be 80°C, 90°C, 100°C, 120°C, 140°C, 160°C, 180°C, or 200°C, but not limited thereto.

[0174] In some embodiments, the duration for heating the precursor solution can be 4 h to 96 h, optionally 6 h to 72 h, but not limited thereto. For example, the duration for heating the precursor solution can be 4 h, 5 h, 7 h, 10 h, 15 h, 20 h, 25 h, 30 h, 35 h, 40 h, 45 h, 48 h, 50 h, 55 h, 60 h, 65 h, 70 h, 75 h, 80 h, 85 h, 90 h, 93 h, or 96 h, but not limited thereto.

[0175] In some embodiments, the obtained metal-organic framework compound can be filtered. Optionally, the obtained metal-organic framework compound can be washed with a washing solvent. The washing solvent can include solvents commonly used in the art, such as methanol, ethanol, acetone, diethyl ether, etc., but not limited thereto. Those skilled in the art can select these post-reaction treatment operations as needed.

[0176] Method for preparing a perovskite solar cell

[0177] The fourth aspect of the present application provides a method for preparing a perovskite solar cell. The method includes:

[0178] providing a first electrode; and

[0179] successively forming a first charge transport layer, a perovskite layer, a second charge transport layer, and a second electrode on the first electrode,

[0180] wherein the step of successively forming a first charge transport layer, a perovskite layer, a second charge transport layer, and a second electrode on the first electrode includes:

[0181] A functional layer is formed on the light-incident side of the perovskite layer, and the functional layer includes the metal-organic framework compound of the first aspect of the present application.

[0182] In some embodiments, the first electrode is a transparent electrode, and the second electrode is a back electrode. The steps of sequentially forming a first charge transport layer, a perovskite layer, a second charge transport layer, and a second electrode on the first electrode include:

[0183] The functional layer is formed at at least one of the following positions: on the side of the first electrode facing away from the first charge transport layer, between the first electrode and the first charge transport layer, and between the first charge transport layer and the perovskite layer.

[0184] In some embodiments, forming the functional layer may include: dissolving the metal-organic framework compound in a solvent to obtain a solution, and coating the solution by spin coating, slot coating, roll coating, blade coating, screen printing, or the like. Here, the solvent is not particularly limited as long as it can dissolve the metal-organic framework compound. For example, the solvent may be acetonitrile, but is not limited thereto.

[0185] The above method can obtain the perovskite solar cell with enhanced optoelectronic performance of the present application simply by adding the operation of applying the functional layer.

[0186] The present application also provides the use of the MOF compound of the first aspect of the present application in a perovskite solar cell for improving the stability of the perovskite layer and / or enhancing the optoelectronic performance of the perovskite solar cell.

[0187] The present application also provides an electrical device, which includes the perovskite solar cell provided by the present application or the perovskite solar cell prepared by the method for preparing the perovskite solar cell according to the present application. The perovskite solar cell can be used as the power source of the electrical device or as the energy storage unit of the electrical device. The electrical device may include: (1) User solar power supply: small power supplies ranging from 10 to 100 W, used for civilian and military living electricity in remote areas without electricity such as plateaus, islands, pastoral areas, border defense posts, etc., such as lighting, televisions, tape recorders, etc., 3 - 5 KW household rooftop grid-connected power generation systems, and photovoltaic pumps: to solve the drinking and irrigation of deep wells in areas without electricity; (2) Transportation field: such as beacon lights, traffic / railway signal lights, traffic warning / sign lights, street lights, high-altitude obstacle lights, highway / railway wireless phone booths, power supply for unmanned shift stations, etc.; (3) Communication / telecommunication field: solar-powered unmanned microwave relay stations, optical cable maintenance stations, radio / communication / paging power supply systems; rural carrier telephone photovoltaic systems, small communication machines, soldier GPS power supply, etc.; (4) Oil, ocean, meteorological fields: solar power supply systems for cathodic protection of oil pipelines and reservoir gates, living and emergency power supplies for oil drilling platforms, ocean detection equipment, meteorological / hydrological observation equipment, etc.; (5) Household lamp power supply: such as garden lights, street lights, hand-held lights, camping lights, mountaineering lights, fishing lights, black lights, rubber tapping lights, energy-saving lamps, etc.; (6) Photovoltaic power stations: 10 KW - 50 MW independent photovoltaic power stations, wind-solar (diesel) hybrid power stations, various large parking lot charging stations, etc.; (7) Solar buildings: combining solar power generation with building materials to enable future large buildings to achieve self-power supply, etc., but not limited thereto.

[0188] In addition, the present application also provides a power generation device, which includes the perovskite solar cell provided by the present application or the perovskite solar cell prepared by the method for preparing the perovskite solar cell according to the present application.

[0189] Examples

[0190] Hereinafter, examples of the present application will be described. The examples described below are exemplary and are only used to explain the present application and should not be construed as a limitation of the present application. For those technologies or conditions not specified in the examples, they shall be carried out according to the technologies or conditions described in the literature in this field or according to the product specifications. For the reagents or instruments not specified by the manufacturer, they are all conventional products that can be obtained through commercial purchase.

[0191] I. Preparation of Metal-Organic Frameworks

[0192] Preparation Example 1: Preparation of Compound PX1

[0193] The metal-organic framework compound was synthesized by the mixed solvent thermal method.

[0194] Lead chloride and terephthalic acid were mixed in a molar ratio of 1:2 and added to a polytetrafluoroethylene inner liner. A mixed solvent was added according to the ratio of lead chloride:solvent = 1 mmol:5.33 mL. The mixed solvent was N,N-dimethylacetamide (DMAC):acetonitrile mixed in a volume ratio of 3:1. Stir at 800 rpm at 25 °C for 30 min to obtain a homogeneous mixed precursor solution. The polytetrafluoroethylene inner liner containing the mixed precursor solution was sealed in a stainless steel container and heated at 120 °C for 48 h, and then cooled to 25 °C at a uniform speed within 72 h. After standing for 120 h, a colorless rod-shaped compound PX1 was obtained. PX1 was filtered, washed several times with absolute ethanol, and dried at 50 °C for 1 h to obtain the MOF compound PX1 with the repeating unit represented by [(Pb2Cl3)(TA)2]·[(CH3)2NH2]3 for standby.

[0195] Preparation Example 2: Preparation of Compound PX2

[0196] Compound PX2 was prepared in the same manner as in Preparation Example 1, except that lead bromide was used instead of lead chloride in Preparation Example 1, to obtain the MOF compound PX2 with the repeating unit represented by [(Pb2Br3)(TA)2]·[(CH3)2NH2]3.

[0197] Preparation Example 3: Preparation of Compound PX3

[0198] Compound PX3 was prepared in the same manner as in Preparation Example 1, except that lead iodide was used instead of lead chloride in Preparation Example 1, to obtain the MOF compound PX3 with the repeating unit represented by [(Pb2I3)(TA)2]·[(CH3)2NH2]3.

[0199] In [(Pb2Cl3)(TA)2]·[(CH3)2NH2]3, [(Pb2Br3)(TA)2]·[(CH3)2NH2]3 or [(Pb2I3)(TA)2]·[(CH3)2NH2]3, TA represents deprotonated terephthalic acid.

[0200] II. Identification of Metal-Organic Framework Compounds

[0201] 1. Test Method for Powder X-Ray Diffraction Pattern

[0202] The X-ray diffraction pattern of the prepared compound was tested using a Bruker X-ray diffractometer. The X-Ray source was a copper target, with wavelengths of Kα1 = 1.54056*10 -10 m and Kα2 = 1.54439*10 -10 m.

[0203] Under room temperature conditions (the instrument room is maintained at 18 °C all year round with dehumidification), Cu target Kα radiation, the operating voltage is 40 kV / mA, the scanning rate is set to 5 sec / step, the scanning step size is 0.02°, and the 2θ angle range of the scanning angle is 5 - 50°.

[0204] 2. Test method for ultraviolet absorption spectrogram

[0205] The ultraviolet absorption spectrogram of the prepared compound was tested using a UV-2600 ultraviolet spectrophotometer from Shimadzu Corporation, Japan.

[0206] Instrument parameters: integrating sphere method, using high-purity BaSO4 as a reference during the test, the scanning wavelength range is set to 200 - 800 nm, and the scanning step size is 1 nm / sec.

[0207] 3. Test method for fluorescence emission spectrogram

[0208] The fluorescence emission spectrogram of the prepared compound was tested using an FLS980 steady-state / transient fluorescence spectrometer from Edinburgh Instruments, UK.

[0209] Instrument parameters: the scanning wavelength is 290 - 800 nm, the scanning step size is 1 nm, the response time is 0.1 - 0.3 seconds, the number of scans is 1 - 3 times, and the instrument slit adapts according to the intensity of the sample emission light.

[0210] According to the fluorescence emission spectrum obtained from the test, the CIE chromaticity coordinate diagram was converted.

[0211] In Figure 2 the powder X-ray diffraction spectrograms of the compounds PX1, PX2, and PX3 prepared in Preparation Examples 1 to 3 of the present application are shown. As Figure 2 shown, the peak shapes and peak positions of the actually synthesized compounds PX1, PX2, and PX3 respectively coincide with the peak shapes and peak positions of the corresponding structure simulations, indicating that the compounds PX1, PX2, and PX3 were prepared in Preparation Examples 1 to 3.

[0212] In Figures 3 to 5 the ultraviolet absorption and fluorescence emission spectrograms of the compounds PX1, PX2, and PX3 prepared in Preparation Examples 1 to 3 of the present application and the CIE chromaticity coordinate diagram of the fluorescence emission are respectively shown.

[0213] As Figure 3 shown, the absorption band of the compound PX1 in Preparation Example 1 is in the range of 200 nm - 400 nm and has no absorption in the visible light band range greater than 400 nm. Its fluorescence emission band is in the range of 400 nm - 700 nm. As Figure 4As shown in the figure, the absorption band of the compound PX2 of Preparation Example 2 is mainly in the range of 200 nm to 400 nm, and there is basically no absorption in the visible light band greater than 400 nm. Its fluorescence emission band is in the range of 400 nm to 800 nm. As Figure 5 As shown in the figure, the absorption band of the compound PX3 of Preparation Example 3 is mainly in the range of 200 nm to 400 nm, and there is basically no absorption in the visible light band greater than 400 nm. Its fluorescence emission band is in the range of 400 nm to 700 nm. These results indicate that the compounds PX1, PX2, and PX3 can absorb the ultraviolet light band that causes perovskite self-degradation, and at the same time emit visible light bands or even near-infrared light bands that can increase the upper limit of the current after perovskite absorption. Thereby, the self-degradation of perovskite can be reduced, the light absorption amount of perovskite can be increased, and then the optoelectronic performance of perovskite solar cells can be enhanced.

[0214] In Figure 6 The structural schematic diagrams of the MOF compounds PX1, PX2, and PX3 prepared in Preparation Examples 1 to 3 of the present application are shown. As Figure 6 As shown in the figure, each asymmetric repeating unit of this type of compound contains two M ions, three halogens X, and two TA ligands, and two dimethylamine cations for balancing charges are contained in the pore cavity. It is composed of a one-dimensional M2X3 + The MO4X3 polyhedral chain composed of the oxygen of the chain-connected ligand L extends in a zigzag chain form along the c-axis in a tetragonal arrangement in a four-sided double-layer network of the tetragonal crystal system.

[0215] III. Preparation of Perovskite Solar Cells

[0216] The perovskite solar cells prepared in Examples 1 to 10 and Comparative Example 1 adopt a 30 cm * 30 cm module structure.

[0217] Example 1

[0218] 1) A set of FTO conductive glass with specifications of 30 cm * 30 cm (fluorine-doped SnO2 conductive glass (SnO2:F), abbreviated as FTO) is used. Infrared laser etching is used to scribe P1, and the width of the scribe P1 is about 30 um. The whole piece of glass is divided into 44 sub-cells in sequence along the long side direction. The series resistance of different sub-cells is greater than 10 MΩ, and the upper and lower 10 mm are used as the areas for module welding; the surface of the etched conductive glass is cleaned twice with acetone and isopropanol in sequence, immersed in deionized water for ultrasonic treatment for 10 min, and then dried in a blast drying oven and placed in a drying room (humidity below 2%), and it is used as the first electrode.

[0219] 2) The cleaned conductive glass is placed in a magnetron sputtering device to deposit a hole transport layer of nickel oxide, and the thickness of the nickel oxide layer film is about 15 nm.

[0220] 3) Dissolve the compound PX1 prepared in Preparation Example 1 above in acetonitrile to prepare a solution with a concentration of 0.05 mg / mL. Coat it on the nickel oxide film layer above by slit coating, then transfer it to a vacuum pumping device and pump it for 60 s under a vacuum degree of 15 Pa, and anneal it for 5 min to obtain a dry film layer of compound PX1 with a thickness of about 2 nm.

[0221] 4) Coat a layer of FA 0.95 Cs 0.05 PbI3 perovskite layer by slit coating, then transfer it to a vacuum pumping device and pump it for 60 s under a vacuum degree of 15 Pa, and anneal it at 150 °C for 10 min using a non-contact closed-space annealing process. The thickness of the perovskite dry film is about 500 nm.

[0222] 5) Put the device prepared above into a vacuum thermal evaporation device, pump it to 4×10 -4 Pa, deposit 30 nm of C60 and 8 nm of BCP (2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline) as the electron transport layer of the device.

[0223] 6) After depositing the electron transport layer in the vacuum thermal evaporation device, continue to deposit 10 nm of Ag on its surface, then break the vacuum and take it out. Laser etch and scribe P2, the width of the P2 scribe line is 150 μm, and etch it to the surface of the FTO layer. The interval between P2 and P1 is 20 μm; then put the substrate into the evaporation device again and pump it to 4×10 -4 Pa, and then continue to deposit a layer of Ag with a thickness of about 80 nm.

[0224] 7) After cooling, break the vacuum and take it out. Use a P-second green laser to etch and scribe P3. The width of the P3 scribe line is 15 μm, and etch it to the surface of the FTO layer. The interval between P3 and P2 is 20 μm (the positions of the scribed lines are P1 / P2 / P3 in sequence).

[0225] 8) Then use infrared edge cleaning on both sides of the component, that is, etch 10 mm on each side of the component.

[0226] 9) Test the energy conversion efficiency of the component under a solar simulator of 1000 W / m 2 .

[0227] Examples 2 to 5

[0228] The preparation processes of Examples 2 to 5 are the same as those of Example 1, except that the dry film thickness of the compound PX1 is different from that of Example 1. The dry film thicknesses of Examples 2 to 5 are 10 nm, 20 nm, 30 nm, and 80 nm respectively. The detailed parameters and results are shown in Table 1.

[0229] Examples 6 and 7

[0230] The preparation processes of Examples 6 and 7 are the same as that of Example 1, except that the MOF compounds are different from those in Example 1. The MOF compounds used in Examples 6 and 7 are compounds PX2 and PX3 prepared in Preparation Example 2 and Preparation Example 3 respectively. The detailed parameters and results are shown in Table 1.

[0231] Examples 8 to 10

[0232] The preparation processes of Examples 8 to 10 are the same as that of Example 1, except that the perovskite materials used are different from those in Example 1. The perovskite materials used in Examples 8 to 10 are CsPbI3, FA 0.95 Cs 0.05 SnI3, FA 0.95 Cs 0.05 Pb(I 0.9 Br 0.1 )3. The detailed parameters and results are shown in Table 1.

[0233] Comparative Example 1

[0234] The preparation process of Comparative Example 1 is the same as that of Example 1, except that no MOF compound is used to set the functional layer.

[0235] IV. Performance Test of Perovskite Solar Cells

[0236] Performance tests were carried out on the perovskite solar cell modules of Examples 1 to 10 and Comparative Example 1.

[0237] Under normal temperature and pressure, using a standard light source of AM1.5G for sunlight simulation, the test was carried out in accordance with the national standard IEC61215. The intensity of the light was calibrated with a crystalline silicon solar cell to reach the intensity of one sun. A four-channel digital source meter (Keithley 2440) was used to measure the volt-ampere characteristic curve of the solar cell under light irradiation, and the open-circuit voltage Voc, short-circuit current density Jsc, fill factor FF (Fill Factor), and energy conversion efficiency Eff (Efficiency) of the solar cell were obtained. The test results are shown in Table 1.

[0238] Table 1: Product parameters and performance test results of perovskite solar cells of Examples 1 to 10 and Comparative Example 1.

[0239]

[0240] According to the above results, the comprehensive optoelectronic performance of the perovskite solar cells of Examples 1 to 10 provided with a functional layer is superior to that of Comparative Example 1 in terms of open-circuit voltage Voc, short-circuit current density Jsc, fill factor FF, energy conversion efficiency Eff, etc. This indicates that, compared with Comparative Example 1, in Examples 1 to 10, the property that the MOF compound in the functional layer absorbs light in the ultraviolet light band and emits light in the visible light band or even in the near-infrared light band has advantageously enhanced the optoelectronic performance of the perovskite solar cells.

[0241] It should be noted that this application is not limited to the above embodiments. The above embodiments are only examples, and embodiments having the same composition and the same effect as the technical idea within the scope of the technical solution of this application are included in the technical scope of this application. In addition, within the scope of not departing from the gist of this application, various modifications that can be conceived by those skilled in the art to the embodiments and other ways constructed by combining some of the constituent elements of the embodiments are also included in the scope of this application.

Claims

1. A metal-organic framework compound, characterized in that, The repeating unit of the metal-organic framework compound is represented by the following formula (I): [(M2X3)(L)2]·[(R)2NH2]3(I) Wherein, M represents a metal center, including at least one of Pb, Sn, Ni, Mn, Co, Cu, Zn, Cr; X includes a halogen; L represents an organic ligand, including at least one of the deprotonated compounds represented by formula (II) or formula (III): In the formula (II) and the formula (III), R1 and R2 each independently include at least one of a substituted or unsubstituted six- to fourteen-membered arylene group, a substituted or unsubstituted C1-C5 alkylene group; R includes at least one of H, C1-C6 alkyl groups.

2. The metal-organic framework compound according to claim 1, wherein When the six- to fourteen-membered arylene group or the C1-C5 alkylene group is substituted, the substituent includes at least one of a hydroxyl group, a carboxyl group, an amide group, an amino group, an aldehyde group, a mercapto group.

3. The metal-organic framework compound according to claim 1 or 2, wherein In the formula (II) and the formula (III), R1 and R2 each independently include at least one of an unsubstituted six- to fourteen-membered arylene group or an unsubstituted C1-C5 alkylene group.

4. The metal-organic framework compound according to any one of claims 1 to 3, characterized in that The organic ligand includes the deprotonated compound of the formula (II).

5. The metal-organic framework compound according to any one of claims 1 to 4, characterized in that, The organic ligand includes the deprotonated compound of the formula (II), and R1 in the formula (II) includes a phenylene group.

6. The metal-organic framework compound according to any one of claims 1 to 5, characterized in that, The M includes at least one of Pb, Sn, Ni.

7. The metal-organic framework compound according to any one of claims 1 to 6, characterized in that, The halogen includes at least one of F, Cl, Br, I.

8. The metal-organic framework compound according to any one of claims 1 to 7, characterized in that, R includes at least one of H, C1-C3 alkyl groups.

9. The metal-organic framework compound according to any one of claims 1 to 8, characterized in that, The repeating unit is represented as [(Pb2Cl3)(TA)2]·[(CH3)2NH2]3, [(Pb2Br3)(TA)2]·[(CH3)2NH2]3 or [(Pb2I3)(TA)2]·[(CH3)2NH2]3, wherein TA represents deprotonated terephthalic acid.

10. The metal-organic framework compound according to any one of claims 1 to 9, wherein the metal-organic framework compound has an ultraviolet absorption band in the range of 200 nm to 400 nm and a fluorescence emission band in the range of 400 nm to 1000 nm.

11. A perovskite solar cell, characterized in that, The perovskite solar cell includes the metal-organic framework compound according to any one of claims 1 to 10.

12. The perovskite solar cell according to claim 11, characterized in that, The perovskite solar cell includes a functional layer, and the functional layer includes the metal-organic framework compound.

13. The perovskite solar cell according to claim 12, wherein, The thickness of the functional layer is 1 nm to 80 nm.

14. The perovskite solar cell according to claim 12 or 13, characterized in that, The perovskite solar cell further includes a perovskite layer, wherein the functional layer is disposed on the light-incident side of the perovskite layer.

15. The perovskite solar cell according to claim 14, characterized in that, A first charge transport layer and a first electrode are sequentially disposed on the light-incident side of the perovskite layer from near to far, and a second charge transport layer and a second electrode are sequentially disposed on the light-emitting side of the perovskite layer from near to far; The functional layer is disposed at at least one of the following positions: between the perovskite layer and the first charge transport layer, between the first charge transport layer and the first electrode, or on the side of the first electrode away from the first charge transport layer.

16. The perovskite solar cell according to claim 15, wherein The perovskite solar cell has one or more of the following characteristics: The first electrode is a transparent electrode; The second electrode is a back electrode; The first charge transport layer is an electron transport layer or a hole transport layer; or The second charge transport layer is an electron transport layer or a hole transport layer, but is different from the first charge transport layer.

17. A method for preparing the metal-organic framework compound according to any one of claims 1 to 10, characterized in that, The method comprises: Mixing at least one of the compounds represented by formula (II) or (III) and a halide of M in a solvent to obtain a precursor solution, wherein the solvent includes a compound represented by formula (IV), wherein R and R4 each independently include at least one of H and a C1-C6 alkyl group; heating the precursor solution in a sealed container; and The heated precursor solution is cooled to obtain the metal organic framework compound.

18. The method according to claim 17, wherein In the formula (IV), R and R4 each independently include at least one of H and C1-C3 alkyl.

19. The method according to claim 17 or 18, characterized in that, The molar ratio between at least one of the compounds represented by the formula (II) or the formula (III) and the halide of M is 1:4 to 4:

1.

20. The method according to any one of claims 17 to 19, characterized in that, The halide of M includes at least one of fluoride, chloride, bromide and iodide of M.

21. The method according to any one of claims 17 to 20, characterized in that The method comprises: mixing the compound represented by the formula (II) and a halide of Pb in a solvent comprising N,N-dimethylacetamide to obtain a precursor solution.

22. A method for preparing a perovskite solar cell, characterized in that, The method comprises: providing a first electrode; and forming a first charge transport layer, a perovskite layer, a second charge transport layer and a second electrode in sequence on the first electrode, The step of sequentially forming a first charge transport layer, a perovskite layer, a second charge transport layer and a second electrode on the first electrode comprises: A functional layer is formed on the light incident side of the perovskite layer, wherein the functional layer comprises the metal organic framework compound according to any one of claims 1 to 10.

23. The method according to claim 22, wherein The first electrode is a transparent electrode, the second electrode is a back electrode, and the steps of sequentially forming a first charge transport layer, a perovskite layer, a second charge transport layer, and a second electrode on the first electrode include: The functional layer is formed at least one of the following positions: on a side of the first electrode facing away from the first charge transport layer, between the first electrode and the first charge transport layer, and between the first charge transport layer and the perovskite layer.

24. A power generation device, characterized in that, The power generation device comprises a perovskite solar cell according to any one of claims 11 to 16 or a perovskite solar cell prepared by the method according to claim 22 or 23.

25. An electrical device, characterized in that, The electrical device comprises a perovskite solar cell according to any one of claims 11 to 16 or a perovskite solar cell prepared by the method according to claim 22 or 23.

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