Solar cell, power utilization device and power generation device

Abstract

The invention provides a solar cell, a power utilization device and a power generation device. The solar cell comprises an active layer, the active layer comprises a first carrier transport layer, a passivation layer and a light absorption layer which are sequentially stacked from top to bottom, and the passivation layer comprises a passivating agent shown in the formula I. The solar cell has excellent photoelectric conversion efficiency and stability.

Description

Technical Field

[0001] This application relates to the field of solar cell device technology, specifically to a solar cell, an electrical device, and a power generation device. Background Technology

[0002] With the large-scale development and utilization of non-renewable energy sources such as coal and oil, their reserves can no longer meet the needs of various industries, including agriculture and manufacturing. Therefore, renewable energy is gradually becoming one of the alternative energy sources to non-renewable energy sources to promote social and industrial development. Among these, solar cell devices are widely used due to their green and environmentally friendly characteristics, as well as their ability to output electricity when exposed to sunlight.

[0003] However, in related technologies, the perovskite material in the light-absorbing layer of solar cells has a large number of vacancy defects on its surface or inside, which is detrimental to carrier transport and degrades the photoelectric conversion efficiency of the solar cell. Using passivating agents to improve the defects of the perovskite material can enhance the photoelectric conversion efficiency of the solar cell. However, commonly used passivating agents in existing technologies are unstable and cause degradation of the perovskite material, worsening the stability and photoelectric conversion efficiency of the solar cell. Therefore, there is an urgent need to provide a stable passivating agent to improve the photoelectric conversion efficiency and stability of solar cells. Summary of the Invention

[0004] This application is made in view of the above-mentioned issues, and its purpose is to provide a solar cell with a passivation layer, which has excellent photoelectric conversion efficiency and stability.

[0005] The first aspect of this application provides a solar cell, which includes an active layer, comprising a first carrier transport layer, a passivation layer and a light-absorbing layer stacked sequentially from top to bottom, and the passivation layer comprising a passivating agent as shown in Formula I.

[0006]

[0007] R2 is selected from substituted or unsubstituted 5- to 12-membered unsaturated rings containing conjugated structures;

[0008] R1 is selected from amino cations, amidine cations, or guanidinium cations;

[0009] L1 is a linker selected from substituted or unsubstituted C1-C3 alkylene, -O-(C1-C3 alkylene)- or -S-(C1-C3 alkylene)-;

[0010] X - It is a negative monovalent halide ion or a pseudohalogen ion;

[0011] q is 0 or 1;

[0012] n is 1 or 2;

[0013] It indicates whether a chemical bond exists or not.

[0014] The amino cations, amido cations, or guanido cations in the passivating agent are linked to the R2 group with a conjugated structure through the linking group L1. This is beneficial for passivating surface defects of perovskite materials and reducing charge recombination at the interface, thereby improving the photoelectric conversion efficiency and stability of solar cells.

[0015] In any embodiment, the aryl group is selected from...

[0016] The heteroaryl group is selected from any one of the following:

[0017] Q and W are heteroatoms, each independently selected from S and N; and Q and W are different. Indicates a single bond or a double bond.

[0018] In any implementation, Q is S and W is N.

[0019] In any embodiment, the aryl group is selected from...

[0020] The heteroaryl group is selected from any one of the following:

[0021]

[0022] Groups with conjugated structures are beneficial for passivating surface defects in perovskite materials, improving the photoelectric conversion efficiency of solar cells, reducing the deprotonation reaction of R1 groups, and improving the stability of passivating agents and solar cells.

[0023] In any embodiment, the electron-withdrawing group includes one or more of halogens, nitro groups, cyano groups, thiocyano groups, and methyl groups substituted with one, two, three, or four halogens.

[0024] In any embodiment, the electron-withdrawing group includes a nitro or a thiocyanate group.

[0025] Replacing the R2 group with a conjugated structure in the passivating agent with an electron-withdrawing group can further reduce the deprotonation reaction of the R1 group, improve the stability of the passivating agent, and thus improve the stability of the solar cell.

[0026] In any embodiment, R1 is selected from amino cations.

[0027] The R1 group in the passivating agent can form coordination bonds, passivate defects in perovskite materials, and thus improve the photoelectric conversion efficiency of solar cells.

[0028] In any implementation, L1 includes one or more of -CH2-, -(CH2)2-, -(CH2)3-, -O-(CH2)2-, and -S-(CH2)2-.

[0029] The linking group L1 in the passivator helps to enhance the interaction between the passivator and the light-absorbing layer, thereby maximizing the passivator's function and improving the photoelectric conversion efficiency and stability of the solar cell.

[0030] In any embodiment, the passivating agent comprises a cation with any of the following structures:

[0031]

[0032] In any embodiment, the monovalent halide ion includes F - Cl - ,Br - I - One or more of the following;

[0033] The monovalent pseudohalogen ions include SCN. - BF4 - PF6 - CN - N3 - OCN - CH3COO - One or more of them.

[0034] In any embodiment, the passivating agent is selected from any one of the following compounds:

[0035]

[0036]

[0037] In any embodiment, the thickness of the passivation layer is 0.1 nm to 50 nm.

[0038] An appropriate passivation layer thickness can effectively reduce nonradiative recombination of charge carriers on the surface, improve charge carrier transport efficiency, and enhance the stability and photoelectric conversion efficiency of the battery.

[0039] In any embodiment, the light-absorbing layer comprises a perovskite compound, the perovskite compound comprising a perovskite material satisfying at least one of ABX3 and / or A2MDX6; wherein A, B, M, and D are all inorganic, organic, or mixed organic-inorganic cations, and A is a monovalent cation including Cs. + K + 、Rb + CH3NH 3+ (methylamine ion), HC(NH2)2+ NH2CH=NH 2+ At least one of (formamidinium ion); B is a divalent cation, including Pb. 2+ Sn 2+ Fe 2+ Mn 2+ Ni 2+ 、Ge 2+ Co 2+ and Sb 2+ At least one of them, Pb 2+ or Sn 2+ M can be Ag + D can be Bi 3+ Sb 3+ In 3+ At least one of the following; X is an inorganic, organic, or mixed organic-inorganic anion, X including Cl - ,Br - I - At least one of them, C1, can be selected. - ,Br - I - .

[0040] The perovskite compound has an adjustable band gap, high carrier mobility, and high light absorption coefficient, which enables the solar cell to have good photoelectric conversion efficiency.

[0041] In any embodiment, the molar ratio of the passivating agent to lead atoms in the perovskite compound is (1-8):100.

[0042] When the molar ratio of passivating agent to lead atoms in perovskite compound is within a suitable range, it is beneficial to form a more uniform and dense passivation film, reduce porosity and defects in the passivation layer, thereby improving the passivation effect of the passivation layer and the stability of solar cells.

[0043] In any implementation, the first carrier in the first carrier transport layer is a free electron or a hole.

[0044] In any embodiment, the solar cell further includes a second carrier transport layer disposed on the side of the light-absorbing layer opposite to the first carrier transport layer; the second carriers in the second carrier transport layer are different from the first carrier transport layer.

[0045] The passivating agent is suitable for both conventional and inverted solar cells. It passivates vacancy defects on the surface or inside the perovskite material in the light-absorbing layer of conventional and inverted solar cells, promotes carrier transport, and improves the photoelectric conversion efficiency of conventional and inverted solar cells.

[0046] A second aspect of this application also provides an electrical device that includes the solar cell of the first aspect of this application.

[0047] A third aspect of this application also provides a power generation device comprising the solar cell of the first aspect of this application.

[0048] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0049] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the embodiments of this application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on the drawings without creative effort.

[0050] Figure 1 This is a schematic diagram of the structure of a solar cell according to one embodiment of this application.

[0051] Explanation of reference numerals in the attached figures:

[0052] 1: Solar cell; 11: Active layer; 10: First electrode layer; 111: First carrier transport layer; 112: Passivation layer; 113: Light-absorbing layer; 114: Second carrier transport layer; 12: Second electrode layer. Detailed Implementation

[0053] Hereinafter, embodiments of the solar cell, power-consuming device, and power-generating device of this application will be described in detail with appropriate reference to the accompanying drawings. However, unnecessary detailed descriptions may be omitted. For example, detailed descriptions of well-known matters and repetitive descriptions of practically identical structures may be omitted. This is to avoid unnecessarily lengthy descriptions and to facilitate understanding by those skilled in the art. Furthermore, the accompanying drawings and the following description are provided for those skilled in the art to fully understand this application and are not intended to limit the subject matter of the claims.

[0054] The "range" disclosed in this application is defined by a lower limit and an upper limit. A given range is defined by selecting a lower limit and an upper limit, which define the boundaries of a particular range. Ranges defined in this way can include or exclude endpoints and can be arbitrarily combined; 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, it is expected that ranges of 60-110 and 80-120 are also included. Furthermore, if minimum range values ​​of 1 and 2 are listed, and if maximum range values ​​of 3, 4, and 5 are listed, then the following ranges are all expected: 1-3, 1-4, 1-5, 2-3, 2-4, and 2-5. In this application, unless otherwise stated, the numerical range "ab" represents a shortened representation of any combination of real numbers between a and b, where a and b are real numbers. For example, the numerical range "0-5" indicates that all real numbers between "0-5" have been listed in this article; "0-5" is simply a shortened representation of these numerical combinations. Furthermore, when a parameter is stated as an integer ≥2, it is equivalent to disclosing that the parameter is, for example, an integer such as 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0055] Unless otherwise specified, all embodiments and optional embodiments of this application can be combined to form new technical solutions.

[0056] Unless otherwise specified, all technical features and optional technical features of this application may be combined to form new technical solutions.

[0057] Unless otherwise specified, all steps in this application may be performed sequentially or randomly, optionally sequentially. For example, the method includes steps (a) and (b), indicating that the method may include steps (a) and (b) performed sequentially, or it may include steps (b) and (a) performed sequentially. For example, the method may also include step (c), indicating that step (c) may be added to the method in any order. For example, the method may include steps (a), (b), and (c), or it may include steps (a), (c), and (b), or it may include steps (c), (a), and (b), etc.

[0058] Unless otherwise specified, the terms "comprising" and "including" as used in this application can be open-ended or closed-ended. For example, "comprising" and "including" can mean that other components not listed may also be included, or that only the listed components may be included.

[0059] Unless otherwise specified, the term "or" is inclusive in this application. For example, the phrase "A or B" means "A, B, or both A and B". More specifically, the condition "A or B" is satisfied by any of the following conditions: A is true (or exists) and B is false (or does not exist); A is false (or does not exist) and B is true (or exists); or both A and B are true (or exist).

[0060] Perovskite solar cells have attracted widespread attention due to their excellent photoelectric properties, such as tunable bandgap, high light absorption coefficient, long carrier lifetime and diffusion length, high defect tolerance, and low-cost low-temperature liquid-phase preparation method. However, the efficiency and stability of perovskite solar cells remain important issues for commercial applications.

[0061] In perovskite solar cells, cations in the perovskite material readily migrate, resulting in numerous vacancy defects on or within the perovskite material. This hinders carrier transport and degrades the photoelectric conversion efficiency of the solar cell. While passivating agents can improve the photoelectric conversion efficiency by mitigating these defects, commonly used ammonium ion-containing passivating agents are prone to deprotonation reactions, leading to perovskite material degradation, deteriorating solar cell stability, and impeding the industrialization of perovskite solar cells.

[0062] [Perovskite Solar Cells]

[0063] Based on this, such as Figure 1 As shown, the first aspect of this application provides a perovskite solar cell 1, including an active layer 11. The active layer 11 includes a first carrier transport layer 111, a passivation layer 112, and a light-absorbing layer 113 stacked sequentially from top to bottom. The passivation layer includes a passivating agent as shown in Formula I.

[0064]

[0065] R2 is selected from 6- to 10-membered monocyclic or fused-ring arylene and 5- to 12-membered monocyclic or fused-ring heteroarylene, wherein each of the arylene and heteroarylene is independently substituted by 0, 1 or 2 electron-withdrawing groups, and the heteroarylene includes 1 to 3 heteroatoms, wherein the heteroatoms include one or more of S and N;

[0066] R1 is selected from amino cations, amidine cations, or guanidinium cations;

[0067] L1 is a linker selected from substituted or unsubstituted C1-C3 alkylene, -O-(C1-C3 alkylene)- or -S-(C1-C3 alkylene)-;

[0068] X - It is a negative monovalent halide ion or a pseudohalogen anion;

[0069] q is 0 or 1;

[0070] n is 1 or 2;

[0071] It indicates whether a chemical bond exists or not.

[0072] In this article, When the chemical bond is absent, the R1 group in Formula I is absent.

[0073] In this paper, the term "6 to 10-membered monocyclic or fused-ring aryl group" refers to the group formed by removing two hydrogen atoms from an aromatic hydrocarbon consisting of 6 to 10 atoms, which can be a single ring or a fused ring.

[0074] In this document, the term "5 to 12-membered monocyclic or fused-ring heteroaryl" refers to a group formed by removing two hydrogen atoms from an aromatic hydrocarbon consisting of 5 to 12 atoms, which may be a single ring or a fused ring, and which contains at least one heteroatom.

[0075] In this paper, the term "electron-withdrawing group" refers to a group that can attract electrons and increase the electron cloud density.

[0076] In this paper, the term "amino cation" refers to a positively charged cation formed by protonation of a molecule containing the NH2R, NHR2, or NR3 structure, where R is a hydrogen atom, methyl, or ethyl.

[0077] In this paper, the term "amidinium cation" refers to a positively charged cation formed by protonation of a molecule containing the HN=C(NH)-R' structure, where R' is a hydrogen atom or a methyl group.

[0078] In this paper, the term "guanidinium cation" refers to a positively charged cation formed by protonation of a molecule containing the H2N-C=NH-NH2 structure.

[0079] In this paper, the term "C1-C3 alkylene" refers to a straight-chain or branched saturated hydrocarbon group containing 1 to 3 carbon atoms.

[0080] In some embodiments, the amino cation includes NH4. + CH3NH3 + CH3CH2NH3 + (CH3)2NH2 + .

[0081] In some embodiments, the amidine cation includes NH2. + =CHNH2.

[0082] In some embodiments, the guanidino cation includes NH2-C(NH2)=NH2 + .

[0083] In some embodiments, the C1-C3 alkylene groups include one or more of methylene (-CH2), ethylene (-CH2-CH2-), and propylene (-CH2-CH2-CH2).

[0084] In some embodiments, the 6- to 10-membered monocyclic or fused-ring arylene and the 5- to 12-membered monocyclic or fused-ring heteroarylene have conjugated structures.

[0085] In this paper, the term "conjugated structure" refers to a group that exhibits a conjugation effect, also known as a delocalization effect. This effect refers to an electronic effect in a conjugated system where the distribution of π electrons (or p electrons) changes due to the interaction between atoms.

[0086] In passivating agents, the R1 group can utilize the lone pair electrons on the nitrogen atom to form coordination bonds with metal ions in the perovskite lattice, reducing active sites and defects in the perovskite material. However, due to the high electron cloud density near the R1 group, deprotonation reactions are prone to occur, leading to degradation of the perovskite material and affecting the stability of the solar cell. The R2 group in the passivating agent has a conjugated structure, which can form chemical bonds with unpaired electrons on the surface of the perovskite material or at grain boundaries, passivating perovskite defects and improving the photoelectric conversion efficiency of the solar cell. Furthermore, the conjugation effect of the conjugated structure expands electron delocalization, reduces the electron cloud density near the R1 group in the passivating agent, enhances the passivating agent's ability to bind protonated hydrogen, and improves the stability of the passivating agent. The linking group L1 in the passivator facilitates the generation of a field effect at the upper interface of the light-absorbing layer, enhancing the interaction between the passivator and the light-absorbing layer, promoting carrier transport, and improving the photoelectric conversion efficiency of the solar cell. Furthermore, the linking group L1 may also improve the stability of the solar cell by increasing the hydrophobicity of the passivator, reducing the impact of air, moisture, and other factors on the light-absorbing layer. Providing a passivation layer containing the aforementioned passivator between the light-absorbing layer and the first carrier transport layer is beneficial for improving the photoelectric conversion efficiency and stability of the solar cell.

[0087] In some embodiments, the arylene group is selected from...

[0088] In some embodiments, the arylene group is selected from...

[0089] In some embodiments, the heteroaryl group is selected from any one of the following:

[0090] Q and W are heteroatoms, each independently selected from S and N; and Q and W are different. Indicates a single bond or a double bond.

[0091] In this application, for any compound or chemical group, the following are connected: The atoms should conform to the rules of chemical bond connection.

[0092] In some embodiments, the heteroaryl group is selected from any one of the following:

[0093] The R2 group in the passivating agent includes the aforementioned groups with conjugated structures. It can not only form chemical bonds with unpaired electrons on the surface of perovskite materials or at grain boundaries, passivating the defects of perovskite materials and improving the photoelectric conversion efficiency of solar cells, but also reduce the electron cloud density near the R1 group in the passivating agent, making the R1 group less prone to deprotonation reactions that could cause degradation of perovskite materials and improve the stability of solar cells.

[0094] In some embodiments, the electron-withdrawing group includes one or more of halogens, nitro groups, cyano groups, thiocyano groups, and methyl groups substituted with one, two, three, or four halogens.

[0095] In this article, the term "halogen" refers to the elements of Group VIIA of the periodic table, including fluorine (F), chlorine (Cl), bromine (Br), and iodine (I).

[0096] In this article, the term "nitro" refers to the -NO2 group.

[0097] In this article, the term "thiocyanate" refers to the -SCN group.

[0098] In some embodiments, the electron-withdrawing group includes a nitro or a thiocyanate group.

[0099] Replacing the R2 group with a conjugated structure in the passivator with an electron-withdrawing group helps to further reduce the electron cloud density near the R1 group in the passivator, making the R1 group less prone to deprotonation and degradation of the perovskite material. Furthermore, when the electron-withdrawing group is attached to the defect site of the perovskite material, it may also stabilize the defect state, reduce the energy of the defect level, reduce non-radiative recombination centers, and promote the transition of charge carriers from the defect state to the conduction band, so that the solar cell can achieve both excellent stability and photoelectric conversion efficiency.

[0100] In some embodiments, when the chemical bond is present, R1 is selected from an amino cation. In some embodiments, when the chemical bond is not present, R1 is selected from an amino cation.

[0101] The R1 group in the passivating agent can form coordination bonds with metal ions in the perovskite lattice using the lone pair electrons on the nitrogen atom, reducing active sites, passivating defects in the perovskite material, and improving the photoelectric conversion efficiency of the solar cell.

[0102] In some embodiments, L1 includes one or more of -CH2-, -(CH2)2-, -(CH2)3-, -O-(CH2)2-, and -S-(CH2)2-.

[0103] The passivator contains a linking group L1, which is beneficial for the passivator to generate a field effect on the upper interface of the light-absorbing layer, enhance the interaction between the passivator and the light-absorbing layer, promote the transport of charge carriers, and improve the photoelectric conversion efficiency of the solar cell. Furthermore, the linking group L1 may also improve the stability of the solar cell by increasing the hydrophobicity of the passivator and reducing the influence of air, moisture and other factors on the light-absorbing layer.

[0104] In some embodiments, q is 0. When q is 0, it represents the case where the R1 group is directly connected to the R2 group and the R3 group. In some embodiments, q is 1.

[0105] When the value of q is within a suitable range, the passivating agent can be prevented from folding and twisting due to excessively long L1 chain length, thereby promoting electron transport and improving the photoelectric conversion efficiency of solar cells.

[0106] In some implementations, n is 1. In some implementations, n is 2.

[0107] In some embodiments, the passivating agent comprises a cation with any of the following structures:

[0108]

[0109]

[0110] In this paper, the term "pseudohalogen" refers to a group of atoms composed of two or more nonmetallic elements that have properties similar to halogens in their free state.

[0111] In some embodiments, the monovalent halide ion includes F - Cl - ,Br - I - One or more of them.

[0112] In some embodiments, the negative monovalent pseudohalogen includes SCN. - BF4 - PF6 - CN - N3 -OCN - CH3COO - One or more of them.

[0113] In some embodiments, the passivating agent is selected from any one of the following compounds:

[0114]

[0115]

[0116] The amino, amidine, or guanidinium cations in the aforementioned passivating agents can form coordination bonds with metal ions in the perovskite lattice using the lone pair electrons on the nitrogen atom, reducing active sites and passivating defects in the perovskite material. The conjugated groups in the passivating agents can not only form chemical bonds with unpaired electrons on the surface of the perovskite material or at grain boundaries, passivating defects and improving the photoelectric conversion efficiency of the solar cell, but also utilize the conjugation effect of the conjugated structure to expand electron delocalization, reduce the electron cloud density of the amino, amidine, or guanidinium cations, improve the ability of the passivating molecules to bind protonated hydrogen, and enhance the stability of the passivating agent and the solar cell. By placing a passivation layer including the aforementioned passivating agents between the light-absorbing layer and the first carrier transport layer, the solar cell achieves both excellent photoelectric conversion efficiency and stability.

[0117] In some embodiments, the passivation layer 112 has a thickness of 0.1 nm to 50 nm. In some embodiments, the passivation layer 112 has a thickness of 1 nm to 15 nm.

[0118] In some embodiments, the thickness of the passivation layer 112 can be selected as 0.1nm-50nm, 1nm-50nm, 5nm-50nm, 10nm-50nm, 15nm-50nm, 20nm-50nm, 25nm-50nm, 30nm-50nm, 35nm-50nm, 40nm-50nm, or 45nm-50nm. In some embodiments, the thickness of the passivation layer 112 is 1nm, 2nm, 5nm, 10nm, 15nm, 20nm, 25nm, 30nm, 35nm, 40nm, 45nm, or 50nm, or a range between any two of these values.

[0119] Excessive passivation layer thickness increases the transport path length of charge carriers from the active region to the electrode, leading to increased series resistance and hindering carrier transport, causing surface recombination and negatively impacting the cell's photoelectric conversion efficiency. Insufficient passivation layer thickness fails to completely passivate defects, making it easier for R1 groups to undergo deprotonation reactions, resulting in degradation of the light-absorbing perovskite material. Appropriate passivation layer thickness effectively prevents non-radiative recombination of charge carriers on the surface, improving carrier transport efficiency and enhancing the stability and photoelectric conversion efficiency of the solar cell.

[0120] In some embodiments, the light-absorbing layer 113 comprises a perovskite compound, and the solar cell is a perovskite cell.

[0121] In some embodiments, the perovskite compound crystal structure satisfies at least one of ABX3 and / or A2MDX6; wherein A, B, M, and D are all inorganic, organic, or mixed organic-inorganic cations, and A is a monovalent cation, including Cs. + K + 、Rb + CH3NH 3+ (Methylamine, MA+), HC(NH2) 2+ NH2CH=NH 2+ (Formamidine, for FA) + At least one of the following: B is a divalent cation, including Pb. 2+ Sn 2+ Fe 2+ Mn 2+ Ni 2+ 、Ge 2+ Co 2+ and Sb 2+ At least one of them, Pb 2+ or Sn 2+ M can be Ag + D can be Bi 3+ Sb 3+ In 3+ At least one of the following; X is an inorganic, organic, or mixed organic-inorganic anion, X including Cl - ,Br - I - At least one of them, C1, can be selected. - ,Br - I - .

[0122] The perovskite compound has an adjustable band gap, high carrier mobility, and high light absorption coefficient, which enables the solar cell to have good photoelectric conversion efficiency.

[0123] In some embodiments, the thickness of the light-absorbing layer 113 is 200nm-1000nm.

[0124] In some embodiments, the thickness of the light-absorbing layer 113 can be selected as 300nm-1000nm, 400nm-1000nm, 500nm-1000nm, 600nm-1000nm, 700nm-1000nm, 800nm-1000nm, or 900nm-1000nm. In some embodiments, the thickness of the light-absorbing layer 113 is 200nm, 300nm, 400nm, 500nm, 600nm, 700nm, 800nm, 900nm, or 1000nm, or within any two values. In some embodiments, the thickness of the light-absorbing layer is 500nm-900nm.

[0125] When the thickness of the perovskite light-absorbing layer is within a suitable range, the solar cell can not only absorb a wide range of solar spectra, but also has excellent charge transport performance.

[0126] In some embodiments, the band gap of the perovskite compound is 1.20 eV to 2.30 eV.

[0127] In some embodiments, the band gap of the perovskite compound may be selected as 1.50 eV–2.30 eV, 1.70 eV–2.30 eV, 1.90 eV–2.30 eV, 2.0 eV–2.30 eV, or 2.20 eV–2.30 eV. In some embodiments, the band gap of the perovskite compound is 1.20 eV, 1.30 eV, 1.40 eV, 1.50 eV, 1.60 eV, 1.70 eV, 1.80 eV, 1.90 eV, 2.00 eV, 2.10 eV, 2.20 eV, or 2.30 eV, or a range between any two of these values.

[0128] If the band gap of the perovskite light-absorbing layer is within the above range, the solar cell can absorb more photons in the spectral range, thereby improving the photoelectric conversion efficiency of the solar cell.

[0129] In some embodiments, the molar ratio of the passivating agent molecules to lead atoms in the perovskite compound is (1-8):100. In some embodiments, the molar ratio of the passivating agent molecules to lead atoms in the perovskite compound is 1:100, 2:100, 3:100, 4:100, 5:100, 6:100, 7:100, 8:100, or a range between any two of these values.

[0130] When the molar ratio of passivating agent to lead atoms in perovskite compound is within a suitable range, it is beneficial to form a more uniform and dense passivation film, reduce porosity and defects in the passivation layer, and improve the passivation capability of the passivation layer and the stability of solar cells.

[0131] In some implementations, the first carrier in the first carrier transport layer 111 is a free electron or a hole.

[0132] In some embodiments, the first carrier transport layer 111 is an electron transport layer, which includes [6,6]-phenyl C 61 Methyl butyrate (PC) 61 BM), [6,6]-phenyl C 71 Methyl butyrate (PC) 71 BM), Fullerene C 60 (C 60 ), fullerene C 70 (C 70 One or more of the following: tin dioxide (SnO2), zinc oxide (ZnO), perylene imide (PDI) materials, and naphthalene imide (NDI) materials.

[0133] In some embodiments, the thickness of the electron transport layer is 5nm-100nm.

[0134] In some embodiments, the thickness of the electron transport layer is 10nm-100nm, 20nm-100nm, 30nm-100nm, 40nm-100nm, 50nm-100nm, 60nm-100nm, 70nm-100nm, 80nm-100nm, or 90nm-100nm. In some embodiments, the thickness of the electron transport layer is 5nm, 10nm, 15nm, 20nm, 25nm, 30nm, 35nm, 40nm, 45nm, 50nm, 55nm, 60nm, 65nm, 70nm, 75nm, 80nm, 85nm, 90nm, 95nm, or 100nm, or a range between any two of these values.

[0135] In some embodiments, the first carrier transport layer 111 is a hole transport layer, which includes a metal oxide, including at least one of nickel oxide, molybdenum oxide, and tungsten oxide.

[0136] In some embodiments, the thickness of the hole transport layer is 10nm-100nm.

[0137] In some embodiments, the thickness of the hole transport layer can be selected as 20nm-100nm, 30nm-100nm, 40nm-100nm, 50nm-100nm, 60nm-100nm, 70nm-100nm, 80nm-100nm, or 90nm-100nm. In some embodiments, the thickness of the electron transport layer is 10nm, 15nm, 20nm, 25nm, 30nm, 35nm, 40nm, 45nm, 50nm, 55nm, 60nm, 65nm, 70nm, 75nm, 80nm, 85nm, 90nm, 95nm, or 100nm, or a range between any two of these values.

[0138] In some implementations, for example Figure 1 The active layer 11 also includes a second carrier transport layer 114 disposed on the side of the light-absorbing layer 113 away from the first carrier transport layer 111. The second carriers of the second carrier transport layer 114 are different from the first carriers in the first carrier transport layer 113.

[0139] In some embodiments, the first carrier transport layer is an electron transport layer, and the second carrier transport layer is a hole transport layer.

[0140] In some implementations, for example Figure 1 The solar cell 1 also includes a first electrode and a second electrode respectively disposed on both sides of the surface of the active layer 11.

[0141] In some embodiments, the first electrode includes a transparent electrode, which includes at least one of fluorine-doped tin oxide, indium tin oxide, zinc aluminum oxide, zinc indium oxide, and zinc gallium oxide.

[0142] In some embodiments, the thickness of the first electrode is 10 nm to 1000 nm.

[0143] In some embodiments, the thickness of the first electrode is 50nm-1000nm, 100nm-1000nm, 150nm-1000nm, 200nm-1000nm, 400nm-1000nm, 600nm-1000nm, 800nm-1000nm, or 900nm-1000nm. In some embodiments, the thickness of the first electrode is 50nm, 100nm, 150nm, 200nm, 250nm, 300nm, 350nm, 400nm, 450nm, 500nm, 550nm, 600nm, 650nm, 700nm, 750nm, 800nm, 850nm, 900nm, 950nm, or 1000nm, or a range between any two of these values.

[0144] In some embodiments, the second electrode comprises an organic, inorganic, or mixed organic-inorganic conductive material, said conductive material comprising at least one of the following: fluorine-doped tin oxide, indium tin oxide, aluminum-doped zinc oxide, gallium zinc oxide, indium zinc oxide, gold, silver, copper, aluminum, nickel, chromium, bismuth, platinum, magnesium, molybdenum, tungsten, or alloys thereof, carbon, graphene, and carbon nanotubes.

[0145] In some embodiments, the thickness of the second electrode layer 12 is 20 nm to 200 nm.

[0146] In some embodiments, the thickness of the second electrode layer 12 is 30nm-200nm, 40nm-200nm, 60nm-200nm, 80nm-200nm, 100nm-200nm, 120nm-200nm, 140nm-200nm, 160nm-200nm, or 180nm-200nm. In some embodiments, the thickness of the second electrode layer 12 can be 20nm, 40nm, 60nm, 80nm, 100nm, 120nm, 140nm, 160nm, 180nm, 200nm, or within any range of the above values.

[0147] In some embodiments, the solar cell 1 is an inverted pin perovskite cell, comprising a first electrode, a second carrier transport layer, a light-absorbing layer, a passivation layer, the first carrier transport layer, and the second electrode stacked sequentially, wherein the second carrier transport layer is a hole transport layer and the first carrier transport layer is an electron transport layer.

[0148] In some embodiments, solar cell 1 is a formal nip perovskite cell, comprising a first electrode, a second carrier transport layer, a light-absorbing layer, a passivation layer, the first carrier transport layer, and a second electrode stacked sequentially, wherein the second carrier transport layer is an electron transport layer and the first carrier transport layer is a hole transport layer.

[0149] In some embodiments, a barrier layer is further present between the electron transport layer and the electrode layer. The barrier layer includes, but is not limited to, the following materials: 2,9-dimethyl-4,7-biphenyl-1,10-o-phenanthroline, SnO2, and ZnO.

[0150] In some embodiments, the thickness of the barrier layer is 0.5 nm to 20 nm. In some embodiments, the thickness of the barrier layer is 1 nm to 20 nm, 2 nm to 20 nm, 4 nm to 20 nm, 8 nm to 20 nm, 12 nm to 20 nm, 16 nm to 20 nm, or 18 nm to 20 nm. In some embodiments, the thickness of the barrier layer is 0.5 nm, 1 nm, 2 nm, 4 nm, 6 nm, 8 nm, 10 nm, 12 nm, 14 nm, 16 nm, 18 nm, 20 nm, or within any range of the above values.

[0151] The solar cell can be obtained by the following methods:

[0152] A first electrode layer is provided; a first carrier transport layer is provided on one side of the first electrode layer; a light-absorbing layer is provided on one side of the first carrier transport layer; a passivation layer is provided on the light-absorbing layer, the passivation layer comprising a passivating agent represented by Formula I; a second carrier transport layer is provided on the passivation layer; and a second electrode layer is provided on the side of the second carrier transport layer away from the passivation layer.

[0153] The solar cell can be obtained by the following methods:

[0154] A first electrode layer is provided; a second carrier transport layer is provided on one side of the first electrode layer, and a light-absorbing layer is provided on one side of the second carrier transport layer; a passivation layer is provided on the light-absorbing layer, the passivation layer comprising a passivating agent represented by Formula I, and a first carrier transport layer is provided on the passivation layer; a second electrode layer is provided on the side of the first carrier transport layer away from the passivation layer.

[0155] In some implementations, the light-absorbing layer and the passivation layer are prepared by stepwise deposition.

[0156] In some embodiments, the light-absorbing layer and the passivation layer are prepared in a one-step process.

[0157] In this paper, the term "one-step method" refers to the formation of the light-absorbing layer and the passivation layer in one step, that is, the light-absorbing layer and the passivation layer are not prepared by step deposition.

[0158] Using the above preparation method, solar cells with high photoelectric conversion efficiency and stability can be prepared.

[0159] A second aspect of this application provides an electrical device, including a solar cell according to an embodiment of this application or a solar cell prepared by a preparation method according to an embodiment of this application.

[0160] A third aspect of this application provides a power generation device, including a solar cell according to an embodiment of this application or a solar cell prepared by a preparation method according to an embodiment of this application.

[0161] In some embodiments, solar cells can be used as power generation devices for electrical devices. The type of power generation device may include, but is not limited to, integrated power generation. The electrical device may include, but is not limited to, mobile devices (e.g., mobile phones, tablets, laptops, calculators, watches, etc.), electric vehicles (e.g., pure electric vehicles, hybrid electric vehicles, plug-in hybrid electric vehicles, electric bicycles, electric scooters, electric golf carts, electric trucks, etc.), automobiles, electric trains, ships and satellites, power generation systems, etc. The location of the power generation device may include, but is not limited to, the roof or back panel of a vehicle.

[0162] Example

[0163] The following embodiments describe the disclosure of this application in more detail. These embodiments are merely illustrative, as various modifications and variations will be apparent to those skilled in the art within the scope of the disclosure of this application. Unless otherwise stated, all parts, percentages, and ratios reported in the following embodiments are based on weight, and all reagents used in the embodiments are commercially available or synthesized by conventional methods and can be used directly without further processing, and the instruments used in the embodiments are commercially available.

[0164] I. Preparation of passivating agent

[0165] Preparation Example 1: 10 mmol of p-trifluoromethylaniline and 20 mL of anhydrous ethanol were added to a clean, dry reaction vessel. The mixture was stirred in an ice-water bath until fully dispersed. Then, 12 mmol of an aqueous solution of hydroiodic acid was added dropwise. After the addition was complete, stirring continued in the ice-water bath for 6 hours. The mixture was then removed and allowed to stand at room temperature. Excess solvent was removed by rotary evaporation, followed by repeated washing with diethyl ether until the product turned white. The product was recrystallized in ethanol to obtain white crystals, which were then dried under vacuum for 12 hours to obtain the passivating agent. (Formula III-1).

[0166] Preparation Examples 2-24: The preparation methods of Preparation Examples 2-24 are basically the same as those of Preparation Example 1. The specific differences in parameters are shown in Table 1.

[0167] Table 1: Passivating agent preparation parameters

[0168]

[0169]

[0170]

[0171]

[0172] II. Fabrication of Solar Cells

[0173] Example 1

[0174] Fabrication of the first electrode: Dimensions: 2.0 × 2.0 cm 2 Fluorine-doped tin oxide transparent conductive glass (FTO conductive glass) was used. 0.35 cm of FTO conductive glass was removed from both ends by laser etching to expose the glass substrate. The etched FTO conductive glass was then ultrasonically cleaned several times with water, acetone, and isopropanol in sequence, and then dried with nitrogen gas for later use as the first electrode.

[0175] Preparation of hole transport layer: FTO conductive glass was treated with ultraviolet ozone, and nickel oxide nanoparticles of 10 mg / mL (water as solvent) were spin-coated at a speed of 4000 rpm. The glass was then annealed on a hot plate at 100℃ for 30 minutes to obtain hole transport layer.

[0176] Preparation of the perovskite light-absorbing layer: 1.7 mmol lead iodide, 1.52 mmol formamidine iodide, and 0.08 mmol cesium iodide were weighed and dissolved in 1 mL of a mixed solution of DMF (dimethylformamide) and DMSO (dimethyl sulfoxide) in a volume ratio of 4:1. The mixture was stirred for 2 h and filtered through a 0.22 μm organic filter membrane to obtain a perovskite precursor solution. The perovskite precursor solution was spin-coated at 5000 rpm for 30 s, and 150 μL of anisole was added dropwise to the center of the substrate in the last 5 s. The substrate was annealed at 100 °C for 40 min and cooled to room temperature to obtain a perovskite light-absorbing layer with a thickness of 500 nm.

[0177] Preparation of passivation layer: A passivating agent with a molar ratio of lead iodide in the perovskite precursor raw material of 5:100 was dissolved in isopropanol, wherein the passivating agent was the passivating agent prepared in Preparation Example 1; the passivating material was spin-coated on the perovskite light-absorbing layer at 3000 rpm and annealed at 100°C for 10 minutes to obtain a passivation layer with a thickness of about 5 nm.

[0178] Preparation of electron transport layer: The electron transport layer [6,6]-phenyl-C61-butyrate methyl ester (PCBM) was spin-coated onto the passivation layer at 1500 rpm and annealed at 100 °C for 10 min. Immediately afterwards, its passivation layer 2,9-dimethyl-4,7-biphenyl-1,10-o-diazaphenanthroline (BCP) was spin-coated at 5000 rpm.

[0179] Preparation of the second electrode: The thin film with the electron transport layer is placed in an evaporation apparatus, and the evaporation vacuum degree is adjusted to 5 × 10⁻⁶.-4 A solar cell 1 was prepared by evaporating an 80 nm metal back electrode Ag at a rate of 0.1 A / s below Pa as the second electrode layer.

[0180] Example 2-23

[0181] The preparation methods of Examples 2-23 are basically the same as those of Example 1, except that the type of passivating agent is adjusted to the passivating agent prepared in Examples 2-23. The specific parameters are shown in Table 2.

[0182] Examples 24-26

[0183] The preparation methods of Examples 24-26 are basically the same as those of Example 13, except that the molar ratio of the passivating agent to lead iodide in the perovskite compound is adjusted. The specific parameters are shown in Table 2.

[0184] Comparative Examples 1-2

[0185] The preparation method of Comparative Example 1 is basically the same as that of Example 1, except that no passivation layer is provided between the perovskite light-absorbing layer and the electron transport layer in Comparative Example 1.

[0186] The preparation method of Comparative Example 2 is basically the same as that of Example 1, except that the passivating agent is the passivating agent prepared in Preparation Example 24.

[0187] III. Testing Methods

[0188] 1. Photoelectric conversion efficiency and stability test

[0189] The perovskite solar cell testing (IV test) used a solar simulator from Guangyan, conforming to the national standard IEC61215. A crystalline silicon solar cell was used to correct the light intensity to achieve a solar intensity of AM1.5. The cell was connected to a digital source meter, and its photoelectric conversion efficiency was measured under illumination. The test voltage range was -0.2V to 1.2V, and the scan rate was 50mV / s. The maximum photoelectric conversion efficiency is the highest efficiency of the device after 1-10 days of natural aging. The maximum photoelectric conversion efficiency on day 30 is the device efficiency after 30 days of storage in a nitrogen atmosphere in the dark. Stability, i.e., the retention rate of the maximum photoelectric conversion efficiency, is represented by the ratio of the maximum photoelectric conversion efficiency on day 30 to the maximum photoelectric conversion efficiency.

[0190] IV. Test Results

[0191] The performance test results of Examples 1-26 and Comparative Examples 1-2 are shown in Table 2.

[0192] Table 2: Performance test results of Examples 1-26 and Comparative Examples 1-2

[0193]

[0194]

[0195] As can be seen from the comparison between Examples 1-26 and Comparative Example 1, the solar cell includes an active layer, which comprises, from bottom to top, a light-absorbing layer, a passivation layer, and a first carrier transport layer. The passivation layer includes the passivating agent shown in Formula I, which can improve the retention rate of the maximum photoelectric conversion efficiency of the solar cell. Among them, the passivating agent in Examples 1-25 can improve the maximum photoelectric conversion efficiency and the retention rate of the maximum photoelectric conversion efficiency of the solar cell.

[0196] As can be seen from the comparison between Examples 1-25 and Comparative Example 2, compared with the straight-chain alkylammonium salt passivators shown in Formula III-24, the passivator provided in this application has a conjugated structure, which can effectively passivate defects in perovskite materials. While improving the maximum photoelectric conversion efficiency, the stability of the solar cell is further improved.

[0197] A comparison of Examples 13, 24-25 and Example 26 shows that when the molar ratio of passivating agent to lead halide is (1-8):100, the maximum photoelectric conversion efficiency and stability of solar cells can be improved.

[0198] As can be seen from the comparison between Examples 4-6, 22-23 and Example 3, when the arylene or heteroarylene groups in the passivating agent are replaced by electron-withdrawing groups, the maximum photoelectric conversion efficiency and stability of the solar cell are further improved.

[0199] As can be seen from Examples 12-16, when the anion in the passivator is a monovalent halide ion or a monovalent pseudohalogen ion, the solar cell has both excellent maximum photoelectric conversion efficiency and stability.

[0200] As can be seen from Examples 17-21, when the linking group L1 in the passivating agent is selected from CH2-, -(CH2)2-, -(CH2)3-, -O-(CH2)2-, or -S-(CH2)2-, the solar cell exhibits both excellent maximum photoelectric conversion efficiency and stability. This may be because the passivating agent with the linker generates a field effect at the upper interface of the light-absorbing layer, enhancing the interaction between the passivating agent and the light-absorbing layer and promoting the transport of charge carriers.

[0201] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and they should all be covered within the scope of the claims and specification of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A solar cell, characterized in that, The solar cell includes an active layer, which comprises a first carrier transport layer, a passivation layer, and a light-absorbing layer stacked sequentially from top to bottom. The passivation layer includes a passivating agent as shown in Formula I. R2 is selected from 6- to 10-membered monocyclic or fused-ring arylene and 5- to 12-membered monocyclic or fused-ring heteroarylene, wherein each of the arylene and heteroarylene is independently substituted by 0, 1 or 2 electron-withdrawing groups, and the heteroarylene includes 1 to 3 heteroatoms, wherein the heteroatoms include one or more of S and N; R1 is selected from amino cations, amidine cations, or guanidinium cations; L1 is a linker selected from substituted or unsubstituted C1-C3 alkylene, -O-(C1-C3 alkylene)- or -S-(C1-C3 alkylene)-; X - It is a negative monovalent halide ion or a pseudohalogen ion; q is 0 or 1; n is 1 or 2; It indicates whether a chemical bond exists or not.

2. The solar cell according to claim 1, characterized in that, The aryl group is selected from The heteroaryl group is selected from any one of the following: Q and W are heteroatoms, each independently selected from S and N; and Q and W are different. Indicates a single bond or a double bond.

3. The solar cell according to claim 1 or 2, characterized in that, Q represents S, and W represents N.

4. The solar cell according to any one of claims 1 to 3, characterized in that, The aryl group is selected from The heteroaryl group is selected from any one of the following:

5. The solar cell according to any one of claims 1 to 4, characterized in that, The electron-withdrawing group includes one or more of halogens, nitro, cyano, thiocyano, and methyl groups substituted with one, two, three, or four halogens.

6. The solar cell according to any one of claims 1 to 5, characterized in that, The electron-withdrawing groups include nitro or thiocyanate.

7. The solar cell according to any one of claims 1 to 6, characterized in that, R1 is selected from amino cations.

8. The solar cell according to any one of claims 1 to 7, characterized in that, L1 includes one or more of -CH2-, -(CH2)2-, -(CH2)3-, -O-(CH2)2-, and -S-(CH2)2-.

9. The solar cell according to any one of claims 1 to 8, characterized in that, The passivating agent includes cations with any of the following structures.

10. The solar cell according to any one of claims 1 to 9, characterized in that, The monovalent halide ions include F - Cl - ,Br - I - One or more of the following; The negative monovalent pseudohalogens include SCN. - BF4 - PF6 - CN - N3 - OCN - CH3COO - One or more of them.

11. The solar cell according to claims 1 to 10, characterized in that, The passivating agent is selected from any one of the following compounds:

12. The solar cell according to any one of claims 1 to 11, characterized in that, The thickness of the passivation layer is 0.1 nm to 50 nm.

13. The solar cell according to any one of claims 1 to 12, characterized in that, The light-absorbing layer comprises a perovskite compound, which includes a perovskite material satisfying at least one of ABX3 and / or A2MDX6; wherein A, B, M, and D are all inorganic, organic, or mixed organic-inorganic cations, and A is a monovalent cation including Cs. + K + 、Rb + CH3NH 3+ HC(NH2) 2+ NH2CH=NH 2+ At least one of them; B is a divalent cation, including Pb 2+ Sn 2+ Fe 2+ Mn 2+ Ni 2+ 、Ge 2+ Co 2+ and Sb 2+ At least one of them, Pb 2+ or Sn 2+ M can be Ag + D can be Bi 3+ Sb 3+ In 3+ At least one of the following; X is an inorganic, organic, or mixed organic-inorganic anion, X including Cl - ,Br - I - At least one of them, C1, can be selected. - ,Br - I - .

14. The solar cell according to claim 13, characterized in that, The molar ratio of the passivating agent to lead atoms in the perovskite compound is (1-8):

100.

15. The solar cell according to any one of claims 1 to 14, characterized in that, The first carrier in the first carrier transport layer is a free electron or a hole.

16. The solar cell according to any one of claims 1 to 15, characterized in that, The solar cell further includes a second carrier transport layer disposed on the side of the light-absorbing layer opposite to the first carrier transport layer; the second carriers in the second carrier transport layer are different from the first carriers in the first carrier transport layer.

17. An electrical device, characterized in that, The solar cell includes any one of claims 1 to 16.

18. A power generation device, characterized in that, The solar cell includes any one of claims 1 to 16.

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