阅读说明：本技术 一种用于钙钛矿太阳能电池的可交联有机配体及其制备方法和应用 (Cross-linkable organic ligand for perovskite solar cell and preparation method and application thereof ) 是由 谭占鳌 马宗文 于 2021-08-26 设计创作，主要内容包括：本发明提供了一种用于钙钛矿太阳能电池的可交联有机配体及其制备方法和应用；该可交联有机配体具有式(I)所示结构；式(I)中,X为烷基取代或未取代的亚甲基,Y为氮或磷,Z为硫、氧或仲氨基,Ar为苯、萘、菲、噻吩、呋喃或杂芳基或烷基取代或未取代的亚甲基,R-(1)为可交联基团；n为0～10的整数。与现有技术相比,本发明提供的可交联有机配体为具有交联和配位双功能的有机小分子,其包括两部分,即配体主体和可交联基团；该可交联有机配体可以在加热或紫外光照条件下进行交联形成不溶的聚合物网络结构,具有抗溶剂和提高钙钛矿太阳能电池稳定性的作用,应用本发明提供的可交联有机配体的钙钛矿太阳能电池性能优异且稳定性高。(The invention provides a crosslinkable organic ligand for a perovskite solar cell, a preparation method and application thereof; the cross-linkable organic ligand has a structure shown in a formula (I); in the formula (I), X is alkyl substituted or unsubstituted methylene, Y is nitrogen or phosphorus, Z is sulfur, oxygen or secondary amino, Ar is benzene, naphthalene, phenanthrene, thiophene, furan or heteroaryl or alkyl substituted or unsubstituted methylene, R is 1 Is a crosslinkable group; n is an integer of 0 to 10. Compared with the prior art, the cross-linkable organic ligand provided by the invention is an organic small ligand with cross-linking and coordination dual functionsA molecule comprising two parts, namely a ligand host and a crosslinkable group; the cross-linkable organic ligand can be cross-linked under the condition of heating or ultraviolet illumination to form an insoluble polymer network structure, has the effects of resisting solvents and improving the stability of the perovskite solar cell, and the perovskite solar cell using the cross-linkable organic ligand provided by the invention has excellent performance and high stability.)

1. A crosslinkable organic ligand for perovskite solar cells having the structure of formula (I):

in the formula (I), X is alkyl substituted or unsubstituted methylene, Y is nitrogen or phosphorus, Z is sulfur, oxygen or secondary amino, Ar is benzene, naphthalene, phenanthrene, thiophene, furan or heteroaryl or alkyl substituted or unsubstituted methylene, R is₁Is a crosslinkable group; n is an integer of 0 to 10.

2. The crosslinkable organic ligand for perovskite solar cell according to claim 1, wherein X is methylene; z is sulfur or oxygen; the R is₁Is vinyl, epoxy, azido or bromo; and n is 1, 2, 3, 4, 5, 6 or 7.

3. The crosslinkable organic ligand for perovskite solar cell according to claim 1, having a structure represented by formula (I-1) or (I-2):

4. a method of preparing a crosslinkable organic ligand for perovskite solar cell as defined in any one of claims 1 to 3, comprising the steps of:

a) mixing a compound with a structure shown in a formula (II), a catalyst and an organic solvent, and adding a compound with a structure shown in a formula (III) for reaction; dripping the obtained reaction product into saline water, and filtering to obtain a crude precipitate;

wherein R is₂Hydroxyl, carboxyl, amino, cyano, sulfydryl, aldehyde group, nitro, sulfonic group, vinyl or halogen; r₃Hydroxyl, carboxyl, amino, cyano, sulfydryl, aldehyde group, nitro, sulfonic group, vinyl or halogen;

b) dissolving the crude precipitate obtained in the step a) and then washing with brine; drying the obtained organic phases with anhydrous sodium sulfate, combining, carrying out rotary evaporation, passing through a silica gel chromatographic column, and obtaining the cross-linkable organic ligand with the structure shown in the formula (I) under a mixed eluent of methanol and dichloromethane.

5. The method according to claim 4, wherein the mixing in step a) is performed under nitrogen atmosphere at room temperature for 0.5-1.5 h;

the reaction temperature is 60-120 ℃, and the reaction time is 12-48 h.

6. A perovskite solar cell, which comprises a substrate, a cathode layer, a cathode transmission layer, a cathode modification layer, a perovskite layer, an anode transmission layer and an anode layer which are contacted in sequence, and is characterized in that the cathode modification layer and/or the perovskite layer are/is prepared from the components of the crosslinkable organic ligand for the perovskite solar cell as claimed in any one of claims 1 to 3.

7. The perovskite solar cell according to claim 6, wherein the cathode modification layer is formed by coating and annealing a solution of cross-linkable organic ligand with a concentration of 0.1-5 mol/L;

the thickness of the cathode modification layer is 1 nm-20 nm.

8. The perovskite solar cell of claim 6, wherein the perovskite layer is prepared from a perovskite dope comprising a perovskite light absorbing layer material and a cross-linkable organic ligand; the concentration of the cross-linkable organic ligand in the perovskite stock solution is 0.05 mg/ml-10 mg/ml.

9. The perovskite solar cell of claim 8, wherein the perovskite light absorption layer material is ABX₃(ii) a Wherein A is CH₃NH₃ ⁺、HC(NH₂)₂ ⁺、CH₃(CH₂)_n·NH₃ ⁺、C₆H₅(CH₂)_n·NH₃ ⁺、Cs⁺B is Pb²⁺、Sn²⁺、Cu²⁺Is one or more of, X is I^-、Br^-、Cl^-One or more of (a).

10. The perovskite solar cell according to any one of claims 6 to 9, wherein the cross-linkable organic ligand undergoes a cross-linking reaction under heating or ultraviolet light.

Technical Field

The invention relates to the technical field of solar cells, in particular to a crosslinkable organic ligand for a perovskite solar cell, and a preparation method and application thereof.

Background

Organic-inorganic halogenated Perovskite Solar Cells (PSCs), a green energy power generation technology, have attracted considerable attention due to their excellent photoelectric properties. In recent years, the power conversion efficiency of single-junction PSCs has exceeded 25%, greatly accelerating the large-scale commercialization of PSCs. However, there are still many limitations in stability, and the requirement of long life cannot be satisfied. Therefore, greater attention should be paid to improving both efficiency and long-term stability.

Surface defects at the junction of the transport layer and the perovskite layer and grain boundary defects of the perovskite film are important factors affecting the efficiency and stability of the PSC device. Firstly, defects existing on the surface of the transmission layer are unfavorable for the performance of the device; therefore, it is necessary to modify the surface thereof or add additives to reduce defects and improve electrical conductivity. In addition, the upper and lower surfaces of the perovskite, which are in contact with the transmission layer, and the grain boundary are also concentration regions of defects; these defects cause non-radiative recombination and severely affect efficiency. In addition, the defects are attack points of external factors such as water, oxygen and the like, and are easy to cause the decomposition of the perovskite; therefore, chemical passivation treatment of perovskite surface defects by using various functional molecules has become a hot spot of current research.

The efficiency and stability of the device are seriously affected by the uncoordinated Pb ions on the surface of the perovskite and at the grain boundary; therefore, the organic molecules capable of coordinating with metal cations are selected to passivate defect sites on the surface and the grain boundary through coordination bonds, and a research method is provided for solving the technical problems. In addition, the organic molecules not only passivate the perovskite defects, but also, due to their generally hydrophobic structure, can form an effective water protective layer to improve the stability of the device.

Crosslinkable organic semiconductors are considered as a promising class of effective materials with great potential in achieving solvent resistance and improving long-term stability. In view of its excellent properties and potential, the design and synthesis of organic molecules with dual functions of cross-linking and coordination may be an effective strategy to passivate defects and improve stability.

Disclosure of Invention

In view of the above, the present invention provides a crosslinkable organic ligand for a perovskite solar cell, and a preparation method and an application thereof, and the perovskite solar cell using the crosslinkable organic ligand provided by the present invention has excellent performance and high stability.

The invention provides a crosslinkable organic ligand for a perovskite solar cell, which has a structure shown as a formula (I):

in the formula (I), X is alkyl substituted or unsubstituted methylene, Y is nitrogen or phosphorus, Z is sulfur, oxygen or secondary amino, Ar is benzene, naphthalene, phenanthrene, thiophene, furan or heteroaryl or alkyl substituted or unsubstituted methylene, R is₁Is a crosslinkable group; n is an integer of 0 to 10.

Preferably, X is methylene; z is sulfur or oxygen; the R is₁Is vinyl, epoxy, azido or bromo; and n is 1, 2, 3, 4, 5, 6 or 7.

Preferably, the compound has a structure represented by the formula (I-1) or (I-2):

the invention also provides a preparation method of the crosslinkable organic ligand for the perovskite solar cell, which comprises the following steps:

a) mixing a compound with a structure shown in a formula (II), a catalyst and an organic solvent, and adding a compound with a structure shown in a formula (III) for reaction; dripping the obtained reaction product into saline water, and filtering to obtain a crude precipitate;

wherein R is₂Hydroxyl, carboxyl, amino, cyano, sulfydryl, aldehyde group, nitro, sulfonic group, vinyl or halogen; r₃Is hydroxyl, carboxyl, amino, cyano, sulfydryl, aldehyde group, nitro, sulfonic group,Vinyl or halogen;

b) dissolving the crude precipitate obtained in the step a) and then washing with brine; drying the obtained organic phases with anhydrous sodium sulfate, combining, carrying out rotary evaporation, passing through a silica gel chromatographic column, and obtaining the cross-linkable organic ligand with the structure shown in the formula (I) under a mixed eluent of methanol and dichloromethane.

Preferably, the mixing process in the step a) is carried out for 0.5 to 1.5 hours under the nitrogen atmosphere at room temperature;

the reaction temperature is 60-120 ℃, and the reaction time is 12-48 h.

The invention also provides a perovskite solar cell, which comprises a substrate, a cathode layer, a cathode transmission layer, a cathode modification layer, a perovskite layer, an anode transmission layer and an anode layer which are sequentially contacted, wherein the cathode modification layer and/or the perovskite layer are/is prepared from the components of the crosslinkable organic ligand for the perovskite solar cell.

Preferably, the cathode modification layer is formed by coating and annealing a crosslinkable organic ligand solution with the concentration of 0.1-5 mol/L;

the thickness of the cathode modification layer is 1 nm-20 nm.

Preferably, the perovskite layer is prepared from a perovskite stock solution comprising a perovskite light-absorbing layer material and a crosslinkable organic ligand; the concentration of the cross-linkable organic ligand in the perovskite stock solution is 0.05 mg/ml-10 mg/ml.

Preferably, the perovskite light absorption layer material is ABX₃(ii) a Wherein A is CH₃NH₃ ⁺、HC(NH₂)₂ ⁺、CH₃(CH₂)_n·NH₃ ⁺、C₆H₅(CH₂)_n·NH₃ ⁺、Cs⁺B is Pb²⁺、Sn²⁺、Cu²⁺Is one or more of, X is I^-、Br^-、Cl^-One or more of (a).

Preferably, the cross-linkable organic ligand undergoes a cross-linking reaction under heat or ultraviolet light.

The invention provides a crosslinkable organic ligand for a perovskite solar cell, a preparation method and application thereof; the cross-linkable organic ligand has a structure shown in a formula (I); in the formula (I), X is alkyl substituted or unsubstituted methylene, Y is nitrogen or phosphorus, Z is sulfur, oxygen or secondary amino, Ar is benzene, naphthalene, phenanthrene, thiophene, furan or heteroaryl or alkyl substituted or unsubstituted methylene, R is₁Is a crosslinkable group; n is an integer of 0 to 10. Compared with the prior art, the cross-linkable organic ligand provided by the invention is an organic micromolecule with cross-linking and coordination dual functions, and comprises two parts, namely a ligand main body (such as phenanthroline ligand) and a cross-linkable group (such as styryl); the cross-linkable organic ligand can be cross-linked under the condition of heating or ultraviolet illumination to form an insoluble polymer network structure, has the effects of resisting solvents and improving the stability of the perovskite solar cell, and the perovskite solar cell using the cross-linkable organic ligand provided by the invention has excellent performance and high stability. The experimental result shows that the defects of the lower surfaces of the tin dioxide and perovskite layers can be passivated simultaneously by selecting the cross-linkable phenanthroline derivative as the material for preparing the cathode modification layer, so that the conductivity of the tin dioxide is improved, and the defects of perovskite are reduced; meanwhile, when the polymer is added into a perovskite layer, the defect of the perovskite layer at the grain boundary can be passivated, a hydrophobic polymer network is formed, and the stability of the device is improved.

In addition, the preparation method provided by the invention has the advantages of simple process, mild and easily-controlled conditions, high yield and wide application prospect.

Drawings

Fig. 1 is a schematic device structure diagram of a perovskite solar cell provided in an embodiment of the invention;

FIG. 2 is a current density versus voltage (J-V) plot of comparative example 1 under illumination with an intensity of 100 milliwatts per square centimeter;

FIG. 3 is a current density versus voltage (J-V) curve for comparative example 2 under illumination with an intensity of 100 milliwatts per square centimeter;

FIG. 4 is a current density versus voltage (J-V) curve for comparative example 3 under illumination with an intensity of 100 milliwatts per square centimeter;

FIG. 5 is a current density versus voltage (J-V) curve for example 1 under illumination with an intensity of 100 milliwatts per square centimeter;

FIG. 6 is a graph of current density versus voltage (J-V) for example 2 under illumination with an intensity of 100 milliwatts per square centimeter;

FIG. 7 is a current density versus voltage (J-V) curve for example 3 under illumination with an intensity of 100 milliwatts per square centimeter;

FIG. 8 is a current density versus voltage (J-V) curve for example 4 under illumination with an intensity of 100 milliwatts per square centimeter;

FIG. 9 is a current density versus voltage (J-V) curve for example 5 under illumination with an intensity of 100 milliwatts per square centimeter;

FIG. 10 is a graph of current density versus voltage (J-V) for example 6 under illumination with an intensity of 100 milliwatts per square centimeter;

FIG. 11 is a graph of current density versus voltage (J-V) for example 7 under illumination with an intensity of 100 milliwatts per square centimeter;

FIG. 12 is a current density versus voltage (J-V) curve for example 8 under illumination with an intensity of 100 milliwatts per square centimeter;

FIG. 13 is a current density versus voltage (J-V) curve for example 9 under illumination with an intensity of 100 milliwatts per square centimeter;

FIG. 14 is a current density versus voltage (J-V) curve for example 10 under illumination with an intensity of 100 milliwatts per square centimeter;

FIG. 15 is a current density versus voltage (J-V) curve for example 11 under illumination with an intensity of 100 milliwatts per square centimeter;

FIG. 16 is a current density versus voltage (J-V) curve for example 12 under illumination with an intensity of 100 milliwatts per square centimeter;

fig. 17 is a graph showing the change in efficiency of the perovskite solar cell prepared under the conditions of comparative example 1 and example 3 under water and heat conditions.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to the following embodiments of the present invention, and it should be understood that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The invention provides a crosslinkable organic ligand for a perovskite solar cell, which has a structure shown as a formula (I):

in the formula (I), X is alkyl substituted or unsubstituted methylene, Y is nitrogen or phosphorus, Z is sulfur, oxygen or secondary amino, Ar is benzene, naphthalene, phenanthrene, thiophene, furan or heteroaryl or alkyl substituted or unsubstituted methylene, R is₁Is a crosslinkable group; n is an integer of 0 to 10.

In the present invention, X is an alkyl substituted or unsubstituted methylene group, preferably a methylene group (unsubstituted methylene group); y is nitrogen or phosphorus, preferably N; z is sulfur, oxygen or a secondary amino group, preferably sulfur or oxygen; ar is benzene, naphthalene, phenanthrene, thiophene, furan, or heteroaryl or an alkyl substituted or unsubstituted methylene (heteroaryl substituted methylene, alkyl substituted methylene or unsubstituted methylene), preferably benzene or methylene; the R is₁Is a crosslinkable group, preferably a vinyl, epoxy, azide or bromide group, more preferably a vinyl group; n is an integer of 0-10, preferably 1, 2, 3, 4, 5, 6 or 7.

In a preferred embodiment of the present invention, the crosslinkable organic ligand has a structure represented by formula (I-1) or (I-2):

the cross-linkable organic ligand provided by the invention is an organic micromolecule with cross-linking and coordination dual functions, and comprises two parts, namely a ligand main body (such as phenanthroline ligand) and a cross-linkable group (such as styryl); the cross-linkable organic ligand can be cross-linked under the condition of heating or ultraviolet illumination to form an insoluble polymer network structure, and has the effects of resisting a solvent and improving the stability of the perovskite solar cell; the perovskite solar cell applying the cross-linkable organic ligand provided by the invention has excellent performance and high stability, namely, the photoelectric conversion efficiency is greatly improved by introducing the organic micromolecules with double functions, and the stability of the device is enhanced.

The invention also provides a preparation method of the crosslinkable organic ligand for the perovskite solar cell, which comprises the following steps:

a) mixing a compound with a structure shown in a formula (II), a catalyst and an organic solvent, and adding a compound with a structure shown in a formula (III) for reaction; dripping the obtained reaction product into saline water, and filtering to obtain a crude precipitate;

wherein R is₂Hydroxyl, carboxyl, amino, cyano, sulfydryl, aldehyde group, nitro, sulfonic group, vinyl or halogen; r₃Hydroxyl, carboxyl, amino, cyano, sulfydryl, aldehyde group, nitro, sulfonic group, vinyl or halogen;

b) dissolving the crude precipitate obtained in the step a) and then washing with brine; drying the obtained organic phases with anhydrous sodium sulfate, combining, carrying out rotary evaporation, passing through a silica gel chromatographic column, and obtaining the cross-linkable organic ligand with the structure shown in the formula (I) under a mixed eluent of methanol and dichloromethane.

Firstly, mixing a compound with a structure shown in a formula (II), a catalyst and an organic solvent, and then adding a compound with a structure shown in a formula (III) for reaction; the obtained reaction product is dropped into brine and filtered to obtain a crude precipitate. The present invention can cause the reaction in the above step to proceed in the compound having the structure represented by the formula (II)R₂And R in the compound with the structure shown as the formula (III)₃Reacting to obtain a reaction product of a crosslinkable organic ligand comprising the structure of formula (I); the specific types of the catalyst and the organic solvent used therein, and the amounts of the raw materials may be selected by those skilled in the art according to the reaction between the compound having the structure represented by formula (II) and the compound having the structure represented by formula (III).

In the present invention, the mixing is preferably performed for 0.5 to 1.5 hours under a nitrogen atmosphere at room temperature, and more preferably for 1 hour under a nitrogen atmosphere at room temperature.

In the invention, the reaction temperature is preferably 60-120 ℃, and more preferably 60-100 ℃; the reaction time is preferably 12 to 48 hours, and more preferably 24 to 36 hours.

After the crude precipitation product is obtained, the crude precipitation product is dissolved and then is washed by brine; drying the obtained organic phases with anhydrous sodium sulfate, combining, carrying out rotary evaporation, passing through a silica gel chromatographic column, and obtaining the cross-linkable organic ligand with the structure shown in the formula (I) under a mixed eluent of methanol and dichloromethane. By adopting the steps, the crosslinkable organic ligand in the crude precipitate product can be separated and purified, and the crosslinkable organic ligand with the structure shown in the formula (I) is obtained.

In the present invention, the dissolution is preferably performed using methylene chloride; the present invention is not particularly limited in its origin, and commercially available products known to those skilled in the art may be used.

The preparation method provided by the invention has the advantages of simple process, mild condition, easy control, high yield and wide application prospect.

The invention also provides a perovskite solar cell, which comprises a substrate, a cathode layer, a cathode transmission layer, a cathode modification layer, a perovskite layer, an anode transmission layer and an anode layer which are sequentially contacted, wherein the cathode modification layer and/or the perovskite layer are/is prepared from the components of the crosslinkable organic ligand for the perovskite solar cell.

In the invention, the cathode modification layer and the perovskite layer can adopt the crosslinkable organic ligand for the perovskite solar cell described in the technical scheme as the additive, so that the photoelectric conversion efficiency is greatly improved by introducing the additive, and the stability of the device is enhanced.

In the present invention, the cross-linkable organic ligand preferably undergoes a cross-linking reaction under heat or ultraviolet light irradiation; the crosslinking reaction can be carried out under the condition of heating or ultraviolet irradiation; wherein the heating temperature is preferably 150-200 ℃, more preferably 180 ℃, and the crosslinking reaction is carried out under the condition of heating for 20-40 min (preferably 30 min); in addition, crosslinking reactions can occur at lower temperatures and in shorter times by introducing small molecules containing polythiol groups (such as PETMP).

The perovskite solar cell provided by the invention has a cell structure as shown in figure 1; fig. 1 is a schematic device structure diagram of a perovskite solar cell provided in an embodiment of the invention; wherein 1 is a substrate; 2 is a transparent conductive metal oxide cathode layer; 3 is a cathode transmission layer; 4 is a cathode modification layer; 5 is a perovskite (additive) layer; 6 is an anode transmission layer; 7 is a metal electrode, and 8 is a metal lead; 9 is a load or test device; 10 is incident light.

The invention has no special requirement on the source of the substrate, and any substrate which is known to those skilled in the art and can be used for solar cells can be adopted, such as glass or polyester film.

The composition of the cathode layer material is not particularly required in the present invention, and any material known to those skilled in the art to be used for a solar cell cathode layer may be used, such as transparent conductive metal oxide Indium Tin Oxide (ITO) or fluorine-doped tin oxide (FTO).

The material of the cathode transmission layer is not particularly required by the invention, and any material which is known to those skilled in the art and can be used for the cathode transmission layer of the solar cell can be adopted, such as tin dioxide or titanium dioxide.

In the invention, the cathode modification layer is preferably formed by coating and annealing a crosslinkable organic ligand solution with the concentration of 0.1-5 mol/L, and more preferably formed by coating and annealing a crosslinkable organic ligand solution with the concentration of 0.1-1 mol/L.

In the present invention, the thickness of the cathode modification layer is preferably 1nm to 20nm, and more preferably 1nm to 10 nm.

In the present invention, the perovskite layer is preferably prepared from a perovskite dope comprising a perovskite light absorbing layer material and a cross-linkable organic ligand; the concentration of the cross-linkable organic ligand in the perovskite stock solution is preferably 0.05mg/ml to 10mg/ml, more preferably 0.05mg/ml to 2 mg/ml.

In the present invention, the perovskite light absorption layer material is preferably ABX₃(ii) a Wherein A is CH₃NH₃ ⁺、HC(NH₂)₂ ⁺、CH₃(CH₂)_n·NH₃ ⁺(n＝1～7)、C₆H₅(CH₂)_n·NH₃ ⁺(n＝1～4)、Cs⁺B is Pb²⁺、Sn²⁺、Cu²⁺Is one or more of, X is I^-、Br^-、Cl^-One or more of (a).

The material of the anode transfer layer is not particularly required by the invention, and any material which is known to those skilled in the art and can be used for the anode transfer layer of the solar cell can be adopted, such as Sprio-OMeTAD or PTAA.

In the present invention, the material of the anode layer is preferably silver or gold, and the thickness of the anode layer is preferably 80nm to 120nm, more preferably 100nm to 110 nm.

In the perovskite solar cell, a metal lead is deposited at one end of a transparent conductive metal oxide cathode layer, the metal lead is connected with the other end of a load or a testing device, the cathode layer is connected with the other end of the load or the testing device, incident light is emitted from the direction of a substrate, and a cathode transmission layer is mainly used for transmitting electrons and blocking holes; the active layer mainly functions to absorb photons and convert them into excitons, causing the excitons to separate into electrons and holes at the donor-acceptor interface; the anode transport layer is used for transporting holes and blocking electrons; the metal electrode functions to collect carriers.

In the present invention, the method for manufacturing a perovskite solar cell preferably includes the steps of:

sequentially coating a cathode layer, a cathode transmission layer, a cathode modification layer, a perovskite (additive) layer and an anode transmission layer on a substrate, and finally evaporating an anode layer to obtain the perovskite solar cell; the material of the cathode modification layer is the crosslinkable organic ligand for the perovskite solar cell in the technical scheme, and the additive material used by the perovskite layer is the crosslinkable organic ligand for the perovskite solar cell in the technical scheme.

Coating a cathode layer, a cathode transmission layer, a cathode modification layer, a perovskite (additive) layer and an anode transmission layer on a substrate in sequence, and finally evaporating an anode layer to obtain the perovskite solar cell; the method for coating each layer is not particularly required, and a person skilled in the art can select a suitable coating mode according to the properties of the material.

In the invention, when the cathode modification layer is coated, the crosslinkable organic ligand is preferably dissolved in the solvent to obtain a crosslinkable organic ligand solution, and then the cathode modification layer is obtained by spin coating; wherein the solvent in the cross-linkable organic ligand solution is preferably an organic solvent, and the organic solvent is preferably one or more of tetrahydrofuran, 1, 4-dioxane, chloroform and N', N-dimethylformamide.

In the present invention, the concentration of the crosslinkable organic ligand solution is preferably 0.1mol/L to 5mol/L, more preferably 0.1mol/L to 2mol/L, more preferably 0.1mol/L to 1.5mol/L, and most preferably 0.1mol/L to 1.2 mol/L. In a preferred embodiment of the present invention, when the crosslinkable organic ligand has a structure represented by formula (I-1), the concentration of the crosslinkable organic ligand solution is preferably 0.1mol/L to 5mol/L, more preferably 0.2mol/L to 2mol/L, more preferably 0.2mol/L to 1mol/L, more preferably 0.3mol/L to 0.5mol/L, and most preferably 0.5 mol/L.

In the present invention, the concentration of the crosslinkable organic ligand in the perovskite dope is preferably 0.05mg/ml to 10mg/ml, more preferably 0.05mg/ml to 2mg/ml, more preferably 0.1mg/ml to 1mg/ml, most preferably 0.2mg/ml, dissolved in the perovskite dope when the perovskite (additive) layer is coated.

In the present invention, the mechanism of action of the crosslinkable organic ligand is: the cross-linkable organic ligand can perform coordination with metal ions in the metal oxide of the cathode transmission layer or metal elements (such as lead ions) of the perovskite, is anchored on the surface of the cathode transmission layer or the perovskite and at the perovskite grain boundary, and then performs cross-linking reaction through heat induction, so that the defects on the surface of the metal oxide and the defects on the surface and the grain boundary of the perovskite are passivated, and the stability and the efficiency are improved.

The invention provides several perovskite solar cells and a preparation method thereof, wherein each perovskite solar cell comprises a substrate, a cathode layer, a cathode transmission layer, a cathode modification layer, an active layer, an anode transmission layer and an anode layer which are contacted in sequence; according to the invention, through selecting the cross-linkable phenanthroline derivative as a material for preparing the cathode modification layer, experimental results show that the defects of the lower surfaces of the tin dioxide and perovskite layers can be passivated simultaneously, the conductivity of the tin dioxide is improved, and the defects of perovskite are reduced; then, when the perovskite nano-material is added into a perovskite layer, the defects at the grain boundary of the perovskite layer can be passivated, a hydrophobic polymer network is formed, and the stability of a device is improved.

The invention provides a crosslinkable organic ligand for a perovskite solar cell, a preparation method and application thereof; the cross-linkable organic ligand has a structure shown in a formula (I); in the formula (I), X is alkyl substituted or unsubstituted methylene, Y is nitrogen or phosphorus, Z is sulfur, oxygen or secondary amino, Ar is benzene, naphthalene, phenanthrene, thiophene, furan or heteroaryl or alkyl substituted or unsubstituted methylene, R is₁Is a crosslinkable group; n is an integer of 0 to 10. Compared with the prior art, the cross-linkable organic ligand provided by the invention is an organic micromolecule with cross-linking and coordination dual functions, and comprises two parts, namely a ligand main body (such as phenanthroline ligand) and a cross-linkable group (such as styryl); the cross-linkable organic ligand can be cross-linked under the condition of heating or ultraviolet illumination to form an insoluble polymer network structure, has the functions of resisting solvents and improving perovskite solar energy electricityThe perovskite solar cell using the crosslinkable organic ligand provided by the invention has excellent performance and high stability. The experimental result shows that the defects of the lower surfaces of the tin dioxide and perovskite layers can be passivated simultaneously by selecting the cross-linkable phenanthroline derivative as the material for preparing the cathode modification layer, so that the conductivity of the tin dioxide is improved, and the defects of perovskite are reduced; meanwhile, when the polymer is added into a perovskite layer, the defect of the perovskite layer at the grain boundary can be passivated, a hydrophobic polymer network is formed, and the stability of the device is improved.

In addition, the preparation method provided by the invention has the advantages of simple process, mild and easily-controlled conditions, high yield and wide application prospect.

To further illustrate the present invention, the following examples are provided for illustration. C1 used in the following examples of the present invention is a crosslinkable organic ligand having a structure represented by formula (I-1), and is specifically prepared as follows:

4, 7-dihydroxy-1, 10-phenanthroline (148mg, 0.69mmol), sodium hydride (57mg, 2.23mmol) and 5ml of DMSO are added into a two-neck flask; stirring the mixed solution for 1h at room temperature under the nitrogen atmosphere; then 4-vinylbenzyl chloride (0.3ml, 1.83mmol) was added and heated at 60 ℃ for 24 h; then dropping the product into brine, filtering to obtain a crude precipitate, dissolving the crude precipitate with dichloromethane, and washing with brine; drying the organic phase with anhydrous sodium sulfate, combining the organic phases, performing rotary evaporation, passing through a silica gel chromatographic column, and obtaining a final product under a mixed eluent of methanol and dichloromethane, wherein the product is a yellow solid, and the yield is 40%; the specific reaction formula is as follows:

c2 is a crosslinkable organic ligand with a structure shown in a formula (I-2), and the preparation method comprises the following steps:

4, 7-dihydroxy-1, 10-phenanthroline (148mg, 0.69mmol), sodium hydride (114mg, 4.46mmol) and 5ml of DMSO are added into a two-neck flask; stirring the mixed solution for 1h at room temperature under the nitrogen atmosphere; then 4-bromo-1-butene (0.25g, 1.83mmol) was added and heated at 100 ℃ for 36 h; then dropping the product into brine, filtering to obtain a crude precipitate, dissolving the crude precipitate with dichloromethane, and then washing with brine; drying the organic phase with anhydrous sodium sulfate, combining the organic phases, performing rotary evaporation, passing through a silica gel chromatographic column, and obtaining a final product under a mixed eluent of methanol and dichloromethane, wherein the product is a yellow solid, and the yield is 36%; the specific reaction formula is as follows:

comparative example 1

1. And cleaning the ITO glass substrate. The substrate cleaning sequence was by ultrasonic cleaning in detergent, water, deionized water, acetone and isopropanol for 15 minutes. The ITO substrate was then dried in an oven at 150 ℃ for 5 minutes and then treated with ultraviolet ozone (UVO) for 15 minutes.

2. And preparing a cathode transmission layer on the ITO transparent conductive layer. SnO₂The diluted solution (diluted with deionized water at a concentration of 2.5%) was spin-coated on an ITO substrate at a speed of 3000rpm, and then it was annealed in an oven at 150 ℃ for 30 minutes to prepare a cathode transfer layer.

3. The perovskite thin film is then deposited on the substrate by a two-step deposition process. First, 50. mu.L of precursor PbI₂Solution (600mg PbI)₂And 92.3 μ L DMSO in 1ml dmf) was coated on the substrate at a speed of 4200rpm, followed by annealing at 70 ℃ for 1 minute. In addition, 50. mu.L of a solution of FAI and MACl (68mg of FAI and 10mg of MACl dissolved in 1ml IPA) was spin-coated onto PbI₂On the film. Subsequently, the perovskite was annealed at 150 ℃ for 20 minutes to obtain a perovskite thin film.

4. An anode transport layer is deposited on the perovskite layer. An anode transport layer was prepared by spin coating a solution of spiro-OMeTAD in chlorobenzene (72.3 mg of spiro-OMeTAD, 28.8. mu.L of TBP and 17.5. mu.L of Li-TFSI solution (520 mg of Li-TFSI in 1ml of acetonitrile)) onto the prepared perovskite thin film to a film thickness of about 200 nm.

5. And finally, preparing an Ag electrode with the thickness of 100nm by adopting a thermal evaporation method to obtain the perovskite solar cell.

Comparative example 2

1. And cleaning the ITO glass substrate. The substrate cleaning sequence was by ultrasonic cleaning in detergent, water, deionized water, acetone and isopropanol for 15 minutes. The ITO substrate was then dried in an oven at 150 ℃ for 5 minutes and then treated with ultraviolet ozone (UVO) for 15 minutes.

2. And preparing a cathode transmission layer on the ITO transparent conductive layer. SnO₂The diluted solution (diluted with deionized water at a concentration of 2.5%) was spin-coated on an ITO substrate at a speed of 3000rpm, and then it was annealed in an oven at 150 ℃ for 30 minutes to prepare a cathode transfer layer.

3. The perovskite thin film is then deposited on the substrate by a two-step deposition process. First, 50. mu.L of precursor PbI₂Solution (461mg PbI)₂Dissolved in 1ml DMF) was coated on the substrate at a speed of 3000 rpm. When the spinning time reached 10 seconds, 50. mu.L of a solution of MAI (50mg of MAI dissolved in 1ml of IPA) was added dropwise to PbI₂On the film. Subsequently, the perovskite was annealed at 150 ℃ for 10 minutes to obtain a perovskite thin film.

4. An anode transport layer is deposited on the perovskite layer. An anode transport layer was prepared by spin coating a solution of spiro-OMeTAD in chlorobenzene (72.3 mg of spiro-OMeTAD, 28.8. mu.L of TBP and 17.5. mu.L of Li-TFSI solution (520 mg of Li-TFSI in 1ml of acetonitrile)) onto the prepared perovskite thin film to a film thickness of about 200 nm.

5. And finally, preparing an Ag electrode with the thickness of 100nm by adopting a thermal evaporation method to obtain the perovskite solar cell.

Comparative example 3

1. And cleaning the ITO glass substrate. The substrate cleaning sequence was by ultrasonic cleaning in detergent, water, deionized water, acetone and isopropanol for 15 minutes. The ITO substrate was then dried in an oven at 150 ℃ for 5 minutes and then treated with ultraviolet ozone (UVO) for 15 minutes.

2. And preparing a cathode transmission layer on the ITO transparent conductive layer. SnO₂A diluent (used at a concentration of 2.5%, diluted with deionized water) toThe cathode transport layer was prepared by spin coating an ITO substrate at 3000rpm and then annealing it in an oven at 150 ℃ for 30 minutes.

3. And then depositing the perovskite thin film on the substrate by a one-step deposition method. First, 50. mu.L of a precursor solution (277mg of PbI)₂312mg CsI, 220mg PbBr and 35mg Pb (Ac)₂Dissolved in 1ml DMSO) were coated onto the substrate at 500rpm and 2500rpm in sequence. Subsequently, the perovskite was annealed at 42 ℃ for 2min, and then subsequently annealed at 160 ℃ for 10 min, to obtain a perovskite thin film.

4. An anode transport layer is deposited on the perovskite layer. Spin coating PM6 chlorobenzene solution (10 mg/ml) on the prepared perovskite thin film, and then thermally evaporating 10nm MoO₃And preparing an anode transmission layer.

5. And finally, preparing an Ag electrode with the thickness of 100nm by adopting a thermal evaporation method to obtain the perovskite solar cell.

Example 1

1. And cleaning the ITO glass substrate. The substrate cleaning sequence was by ultrasonic cleaning in detergent, water, deionized water, acetone and isopropanol for 15 minutes. The ITO substrate was then dried in an oven at 150 ℃ for 5 minutes and then treated with ultraviolet ozone (UVO) for 15 minutes.

2. And preparing a cathode transmission layer on the ITO transparent conductive layer. SnO₂The diluted solution (diluted with deionized water at a concentration of 2.5%) was spin-coated on an ITO substrate at a speed of 3000rpm, and then it was annealed in an oven at 150 ℃ for 30 minutes to prepare a cathode transfer layer. C1 was dissolved in 0.5mg/mL 1, 4-dioxane and spin coated on SnO at 3000rpm₂And annealing the substrate at 180 ℃ for 30min to obtain the cathode modification layer.

3. The perovskite thin film is then deposited on the substrate by a two-step deposition process. First, 50. mu.L of precursor PbI₂The solution (600mg of PbI2 and 92.3. mu.L of DMSO dissolved in 1ml of DMF) was coated on the substrate at a speed of 4200rpm, followed by annealing at 70 ℃ for 1 minute. In addition, 50. mu.L of a solution of FAI and MACl (68mg of FAI and 10mg of MACl dissolved in 1ml of IPA) was spin-coated on PbI₂On the film. Subsequently, the perovskite is annealed at 150 DEG CAnd firing for 20 minutes to obtain the perovskite thin film.

4. An anode transport layer is deposited on the perovskite layer. An anode transport layer was prepared by spin coating a solution of spiro-OMeTAD in chlorobenzene (72.3 mg of spiro-OMeTAD, 28.8. mu.L of TBP and 17.5. mu.L of Li-TFSI solution (520 mg of Li-TFSI in 1ml of acetonitrile)) onto the prepared perovskite thin film to a film thickness of about 200 nm.

5. And finally, preparing an Ag electrode with the thickness of 100nm by adopting a thermal evaporation method to obtain the perovskite solar cell.

Example 2

1. And cleaning the ITO glass substrate. The substrate cleaning sequence was by ultrasonic cleaning in detergent, water, deionized water, acetone and isopropanol for 15 minutes. The ITO substrate was then dried in an oven at 150 ℃ for 5 minutes and then treated with ultraviolet ozone (UVO) for 15 minutes.

2. And preparing a cathode transmission layer on the ITO transparent conductive layer. SnO₂The diluted solution (diluted with deionized water at a concentration of 2.5%) was spin-coated on an ITO substrate at a speed of 3000rpm, and then it was annealed in an oven at 150 ℃ for 30 minutes to prepare a cathode transfer layer.

3. The perovskite thin film is then deposited on the substrate by a two-step deposition process. First, 50. mu.L of precursor PbI₂Solution (600mg PbI)₂And 92.3. mu.L of DMSO was dissolved in 1ml of DMF. Wherein 0.02mg/ml of C1 and PETMP (molar ratio of 2: 1) is added with PbI₂Precursor solution) was coated on the substrate at 4200rpm, followed by annealing at 70 ℃ for 1 minute. In addition, 50. mu.L of a solution of FAI and MACl (68mg of FAI and 10mg of MACl dissolved in 1ml IPA) was spin-coated onto PbI₂On the film. Subsequently, the perovskite was annealed at 150 ℃ for 20 minutes to obtain a perovskite thin film.

4. An anode transport layer is deposited on the perovskite layer. An anode transport layer was prepared by spin coating a solution of spiro-OMeTAD in chlorobenzene (72.3 mg of spiro-OMeTAD, 28.8. mu.L of TBP and 17.5. mu.L of Li-TFSI solution (520 mg of Li-TFSI in 1ml of acetonitrile)) onto the prepared perovskite thin film to a film thickness of about 200 nm.

5. And finally, preparing an Ag electrode with the thickness of 100nm by adopting a thermal evaporation method to obtain the perovskite solar cell.

Example 3

1. And cleaning the ITO glass substrate. The substrate cleaning sequence was by ultrasonic cleaning in detergent, water, deionized water, acetone and isopropanol for 15 minutes. The ITO substrate was then dried in an oven at 150 ℃ for 5 minutes and then treated with ultraviolet ozone (UVO) for 15 minutes.

2. And preparing a cathode transmission layer on the ITO transparent conductive layer. SnO₂The diluted solution (diluted with deionized water at a concentration of 2.5%) was spin-coated on an ITO substrate at a speed of 3000rpm, and then it was annealed in an oven at 150 ℃ for 30 minutes to prepare a cathode transfer layer. C1 was dissolved in 0.5mg/mL 1, 4-dioxane and spin coated on SnO at 3000rpm₂And annealing the substrate at 180 ℃ for 30min to obtain the cathode modification layer.

3. The perovskite thin film is then deposited on the substrate by a two-step deposition process. First, 50. mu.L of precursor PbI₂Solution (600mg PbI)₂And 92.3. mu.L of DMSO was dissolved in 1ml of DMF. Wherein 0.02mg/ml of C1 and PETMP (molar ratio of 2: 1) is added with PbI₂Precursor solution) was coated on the substrate at a speed of 4200rpm, followed by annealing at 70 ℃ for 1 minute. In addition, 50. mu.L of a solution of FAI and MACl (68mg of FAI and 10mg of MACl dissolved in 1ml IPA) was spin-coated onto PbI₂On the film. Subsequently, the perovskite was annealed at 150 ℃ for 20 minutes to obtain a perovskite thin film.

4. An anode transport layer is deposited on the perovskite layer. An anode transport layer was prepared by spin coating a solution of spiro-OMeTAD in chlorobenzene (72.3 mg of spiro-OMeTAD, 28.8. mu.L of TBP and 17.5. mu.L of Li-TFSI solution (520 mg of Li-TFSI in 1ml of acetonitrile)) onto the prepared perovskite thin film to a film thickness of about 200 nm.

5. And finally, preparing an Ag electrode with the thickness of 100nm by adopting a thermal evaporation method to obtain the perovskite solar cell.

Example 4

1. And cleaning the ITO glass substrate. The substrate cleaning sequence was by ultrasonic cleaning in detergent, water, deionized water, acetone and isopropanol for 15 minutes. The ITO substrate was then dried in an oven at 150 ℃ for 5 minutes and then treated with ultraviolet ozone (UVO) for 15 minutes.

2. And preparing a cathode transmission layer on the ITO transparent conductive layer. SnO₂The diluted solution (diluted with deionized water at a concentration of 2.5%) was spin-coated on an ITO substrate at a speed of 3000rpm, and then it was annealed in an oven at 150 ℃ for 30 minutes to prepare a cathode transfer layer. C1 was dissolved in 0.5mg/mL 1, 4-dioxane and spin coated on SnO at 3000rpm₂And annealing the substrate at 180 ℃ for 30min to obtain the cathode modification layer.

3. The perovskite thin film is then deposited on the substrate by a two-step deposition process. First, 50. mu.L of precursor PbI₂Solution (461mg PbI)₂Dissolved in 1ml DMF) was coated on the substrate at a speed of 3000 rpm. When the spinning time reached 10 seconds, 50. mu.L of a solution of MAI (50mg of MAI dissolved in 1ml of IPA) was added dropwise to PbI₂On the film. Subsequently, the perovskite was annealed at 150 ℃ for 10 minutes to obtain a perovskite thin film.

4. An anode transport layer is deposited on the perovskite layer. An anode transport layer was prepared by spin coating a solution of spiro-OMeTAD in chlorobenzene (72.3 mg of spiro-OMeTAD, 28.8. mu.L of TBP and 17.5. mu.L of Li-TFSI solution (520 mg of Li-TFSI in 1ml of acetonitrile)) onto the prepared perovskite thin film to a film thickness of about 200 nm.

5. And finally, preparing an Ag electrode with the thickness of 100nm by adopting a thermal evaporation method to obtain the perovskite solar cell.

Example 5

1. And cleaning the ITO glass substrate. The substrate cleaning sequence was by ultrasonic cleaning in detergent, water, deionized water, acetone and isopropanol for 15 minutes. The ITO substrate was then dried in an oven at 150 ℃ for 5 minutes and then treated with ultraviolet ozone (UVO) for 15 minutes.

2. And preparing a cathode transmission layer on the ITO transparent conductive layer. SnO₂A diluted solution (diluted with deionized water at a concentration of 2.5%) was spin-coated on an ITO substrate at a speed of 3000rpm, and then it was annealed in an oven at 150 ℃ for 30 minutes to prepare a negative electrodeA polar transport layer.

3. The perovskite thin film is then deposited on the substrate by a two-step deposition process. First, 50. mu.L of precursor PbI₂Solution (461mg PbI)₂Dissolved in 1ml DMF. Wherein 0.02mg/ml of C1 and PETMP (molar ratio of 2: 1) is added with PbI₂Precursor solution) was coated on the substrate at a speed of 3000 rpm. When the spinning time reached 10 seconds, 50. mu.L of a solution of MAI (50mg of MAI dissolved in 1ml of IPA) was added dropwise to PbI₂On the film. Subsequently, the perovskite was annealed at 150 ℃ for 10 minutes to obtain a perovskite thin film.

4. An anode transport layer is deposited on the perovskite layer. An anode transport layer was prepared by spin coating a solution of spiro-OMeTAD in chlorobenzene (72.3 mg of spiro-OMeTAD, 28.8. mu.L of TBP and 17.5. mu.L of Li-TFSI solution (520 mg of Li-TFSI in 1ml of acetonitrile)) onto the prepared perovskite thin film to a film thickness of about 200 nm.

5. And finally, preparing an Ag electrode with the thickness of 100nm by adopting a thermal evaporation method to obtain the perovskite solar cell.

Example 6

1. And cleaning the ITO glass substrate. The substrate cleaning sequence was by ultrasonic cleaning in detergent, water, deionized water, acetone and isopropanol for 15 minutes. The ITO substrate was then dried in an oven at 150 ℃ for 5 minutes and then treated with ultraviolet ozone (UVO) for 15 minutes.

2. And preparing a cathode transmission layer on the ITO transparent conductive layer. SnO₂The diluted solution (diluted with deionized water at a concentration of 2.5%) was spin-coated on an ITO substrate at a speed of 3000rpm, and then it was annealed in an oven at 150 ℃ for 30 minutes to prepare a cathode transfer layer. C1 was dissolved in 0.5mg/mL 1, 4-dioxane and spin coated on SnO at 3000rpm₂And annealing the substrate at 180 ℃ for 30min to obtain the cathode modification layer.

3. The perovskite thin film is then deposited on the substrate by a two-step deposition process. First, 50. mu.L of precursor PbI₂Solution (461mg PbI)₂Dissolved in 1ml DMF. Wherein 0.02mg/ml of C1 and PETMP (molar ratio of 2: 1) is added with PbI₂Precursor solution) at 3000rpmCoated on a substrate at speed. When the spinning time reached 10 seconds, 50. mu.L of a solution of MAI (50mg of MAI dissolved in 1ml of IPA) was added dropwise to PbI₂On the film. Subsequently, the perovskite was annealed at 150 ℃ for 10 minutes to obtain a perovskite thin film.

4. An anode transport layer is deposited on the perovskite layer. An anode transport layer was prepared by spin coating a solution of spiro-OMeTAD in chlorobenzene (72.3 mg of spiro-OMeTAD, 28.8. mu.L of TBP and 17.5. mu.L of Li-TFSI solution (520 mg of Li-TFSI in 1ml of acetonitrile)) onto the prepared perovskite thin film to a film thickness of about 200 nm.

5. And finally, preparing an Ag electrode with the thickness of 100nm by adopting a thermal evaporation method to obtain the perovskite solar cell.

Example 7

1. And cleaning the ITO glass substrate. The substrate cleaning sequence was by ultrasonic cleaning in detergent, water, deionized water, acetone and isopropanol for 15 minutes. The ITO substrate was then dried in an oven at 150 ℃ for 5 minutes and then treated with ultraviolet ozone (UVO) for 15 minutes.

2. And preparing a cathode transmission layer on the ITO transparent conductive layer. SnO₂The diluted solution (diluted with deionized water at a concentration of 2.5%) was spin-coated on an ITO substrate at a speed of 3000rpm, and then it was annealed in an oven at 150 ℃ for 30 minutes to prepare a cathode transfer layer. C1 was dissolved in 0.5mg/mL 1, 4-dioxane and spin coated on SnO at 3000rpm₂And annealing the substrate at 180 ℃ for 30min to obtain the cathode modification layer.

3. And then depositing the perovskite thin film on the substrate by a one-step deposition method. First, 50. mu.L of a precursor solution (277mg of PbI)₂312mg CsI, 220mg PbBr and 35mg Pb (Ac)₂Dissolved in 1ml DMSO) were coated onto the substrate at 500rpm and 2500rpm in sequence. Subsequently, the perovskite was annealed at 42 ℃ for 2min, and then subsequently annealed at 160 ℃ for 10 min, to obtain a perovskite thin film.

4. An anode transport layer is deposited on the perovskite layer. Spin coating PM6 chlorobenzene solution (10 mg/ml) on the prepared perovskite thin film, and then thermally evaporating 10nm MoO₃Preparation of anode transportAnd (3) a layer.

5. And finally, preparing an Ag electrode with the thickness of 100nm by adopting a thermal evaporation method to obtain the perovskite solar cell.

Example 8

1. And cleaning the ITO glass substrate. The substrate cleaning sequence was by ultrasonic cleaning in detergent, water, deionized water, acetone and isopropanol for 15 minutes. The ITO substrate was then dried in an oven at 150 ℃ for 5 minutes and then treated with ultraviolet ozone (UVO) for 15 minutes.

2. And preparing a cathode transmission layer on the ITO transparent conductive layer. SnO₂The diluted solution (diluted with deionized water at a concentration of 2.5%) was spin-coated on an ITO substrate at a speed of 3000rpm, and then it was annealed in an oven at 150 ℃ for 30 minutes to prepare a cathode transfer layer.

3. And then depositing the perovskite thin film on the substrate by a one-step deposition method. First, 50. mu.L of a precursor solution (277mg of PbI)₂312mg CsI, 220mg PbBr and 35mg Pb (Ac)₂Dissolved in 1ml DMSO. Wherein, 0.02mg/ml of C1 and PETMP (molar ratio is 2: 1) are added into the precursor solution) and coated on the substrate at the speed of 500rpm and 2500 rpm. Subsequently, the perovskite was annealed at 42 ℃ for 2min, and then subsequently annealed at 160 ℃ for 10 min, to obtain a perovskite thin film.

4. An anode transport layer is deposited on the perovskite layer. Spin coating PM6 chlorobenzene solution (10 mg/ml) on the prepared perovskite thin film, and then thermally evaporating 10nm MoO₃And preparing an anode transmission layer.

5. And finally, preparing an Ag electrode with the thickness of 100nm by adopting a thermal evaporation method to obtain the perovskite solar cell.

Example 9

1. And cleaning the ITO glass substrate. The substrate cleaning sequence was by ultrasonic cleaning in detergent, water, deionized water, acetone and isopropanol for 15 minutes. The ITO substrate was then dried in an oven at 150 ℃ for 5 minutes and then treated with ultraviolet ozone (UVO) for 15 minutes.

2. And preparing a cathode transmission layer on the ITO transparent conductive layer. SnO₂Diluent (2.5% strength by deionized water) at 30The cathode transport layer was prepared by spin coating an ITO substrate at 00rpm and then annealing it in an oven at 150 ℃ for 30 minutes. C1 was dissolved in 0.5mg/mL 1, 4-dioxane and spin coated on SnO at 3000rpm₂And annealing the substrate at 180 ℃ for 30min to obtain the cathode modification layer.

3. And then depositing the perovskite thin film on the substrate by a one-step deposition method. First, 50. mu.L of a precursor solution (277mg of PbI)₂312mg CsI, 220mg PbBr and 35mg Pb (Ac)₂Dissolved in 1ml DMSO. Wherein, 0.02mg/ml of C1 and PETMP (molar ratio is 2: 1) are added into the precursor solution) and coated on the substrate at the speed of 500rpm and 2500 rpm. Subsequently, the perovskite was annealed at 42 ℃ for 2min, and then subsequently annealed at 160 ℃ for 10 min, to obtain a perovskite thin film.

4. An anode transport layer is deposited on the perovskite layer. Spin coating PM6 chlorobenzene solution (10 mg/ml) on the prepared perovskite thin film, and then thermally evaporating 10nm MoO₃And preparing an anode transmission layer.

5. And finally, preparing an Ag electrode with the thickness of 100nm by adopting a thermal evaporation method to obtain the perovskite solar cell.

Example 10

1. And cleaning the ITO glass substrate. The substrate cleaning sequence was by ultrasonic cleaning in detergent, water, deionized water, acetone and isopropanol for 15 minutes. The ITO substrate was then dried in an oven at 150 ℃ for 5 minutes and then treated with ultraviolet ozone (UVO) for 15 minutes.

2. And preparing a cathode transmission layer on the ITO transparent conductive layer. SnO₂The diluted solution (diluted with deionized water at a concentration of 2.5%) was spin-coated on an ITO substrate at a speed of 3000rpm, and then it was annealed in an oven at 150 ℃ for 30 minutes to prepare a cathode transfer layer. C2 was dissolved in 0.5mg/mL 1, 4-dioxane and spin coated on SnO at 3000rpm₂And annealing the substrate at 180 ℃ for 30min to obtain the cathode modification layer.

3. The perovskite thin film is then deposited on the substrate by a two-step deposition process. First, 50. mu.L of precursor PbI₂Solution (600mg PbI)₂And 92.3 μ L DMSO dissolved in 1ml DMF) was coated on the substrate at a speed of 4200rpm, followed by annealing at 70 ℃ for 1 minute. In addition, 50. mu.L of a solution of FAI and MACl (68mg of FAI and 10mg of MACl dissolved in 1ml of IPA) was spin-coated on PbI₂On the film. Subsequently, the perovskite was annealed at 150 ℃ for 20 minutes to obtain a perovskite thin film.

4. An anode transport layer is deposited on the perovskite layer. An anode transport layer was prepared by spin coating a solution of spiro-OMeTAD in chlorobenzene (72.3 mg of spiro-OMeTAD, 28.8. mu.L of TBP and 17.5. mu.L of Li-TFSI solution (520 mg of Li-TFSI in 1ml of acetonitrile)) onto the prepared perovskite thin film to a film thickness of about 200 nm.

5. And finally, preparing an Ag electrode with the thickness of 100nm by adopting a thermal evaporation method to obtain the perovskite solar cell.

Example 11

1. And cleaning the ITO glass substrate. The substrate cleaning sequence was by ultrasonic cleaning in detergent, water, deionized water, acetone and isopropanol for 15 minutes. The ITO substrate was then dried in an oven at 150 ℃ for 5 minutes and then treated with ultraviolet ozone (UVO) for 15 minutes.

2. And preparing a cathode transmission layer on the ITO transparent conductive layer. SnO₂The diluted solution (diluted with deionized water at a concentration of 2.5%) was spin-coated on an ITO substrate at a speed of 3000rpm, and then it was annealed in an oven at 150 ℃ for 30 minutes to prepare a cathode transfer layer.

3. The perovskite thin film is then deposited on the substrate by a two-step deposition process. First, 50. mu.L of precursor PbI₂Solution (600mg PbI)₂And 92.3. mu.L of DMSO was dissolved in 1ml of DMF. Wherein 0.02mg/ml of C2 and PETMP (molar ratio of 2: 1) is added with PbI₂Precursor solution) was coated on the substrate at 4200rpm, followed by annealing at 70 ℃ for 1 minute. In addition, 50. mu.L of a solution of FAI and MACl (68mg of FAI and 10mg of MACl dissolved in 1ml of IPA) was spin-coated on PbI₂On the film. Subsequently, the perovskite was annealed at 150 ℃ for 20 minutes to obtain a perovskite thin film.

4. An anode transport layer is deposited on the perovskite layer. An anode transport layer was prepared by spin coating a solution of spiro-OMeTAD in chlorobenzene (72.3 mg of spiro-OMeTAD, 28.8. mu.L of TBP and 17.5. mu.L of Li-TFSI solution (520 mg of Li-TFSI in 1ml of acetonitrile)) onto the prepared perovskite thin film to a film thickness of about 200 nm.

5. And finally, preparing an Ag electrode with the thickness of 100nm by adopting a thermal evaporation method to obtain the perovskite solar cell.

Example 12

1. And cleaning the ITO glass substrate. The substrate cleaning sequence was by ultrasonic cleaning in detergent, water, deionized water, acetone and isopropanol for 15 minutes. The ITO substrate was then dried in an oven at 150 ℃ for 5 minutes and then treated with ultraviolet ozone (UVO) for 15 minutes.

2. And preparing a cathode transmission layer on the ITO transparent conductive layer. SnO₂The diluted solution (diluted with deionized water at a concentration of 2.5%) was spin-coated on an ITO substrate at a speed of 3000rpm, and then it was annealed in an oven at 150 ℃ for 30 minutes to prepare a cathode transfer layer. C2 was dissolved in 0.5mg/mL 1, 4-dioxane and spin coated on SnO at 3000rpm₂And annealing the substrate at 180 ℃ for 30min to obtain the cathode modification layer.

3. The perovskite thin film is then deposited on the substrate by a two-step deposition process. First, 50. mu.L of precursor PbI₂Solution (600mg PbI)₂And 92.3. mu.L of DMSO was dissolved in 1ml of DMF. Wherein 0.02mg/ml of C2 and PETMP (molar ratio of 2: 1) is added with PbI₂Precursor solution) was coated on the substrate at a speed of 4200rpm, followed by annealing at 70 ℃ for 1 minute. In addition, 50. mu.L of a solution of FAI and MACl (68mg of FAI and 10mg of MACl dissolved in 1ml of IPA) was spin-coated on PbI₂On the film. Subsequently, the perovskite was annealed at 150 ℃ for 20 minutes to obtain a perovskite thin film.

4. An anode transport layer is deposited on the perovskite layer. An anode transport layer was prepared by spin coating a solution of spiro-OMeTAD in chlorobenzene (72.3 mg of spiro-OMeTAD, 28.8. mu.L of TBP and 17.5. mu.L of Li-TFSI solution (520 mg of Li-TFSI in 1ml of acetonitrile)) onto the prepared perovskite thin film to a film thickness of about 200 nm.

5. And finally, preparing an Ag electrode with the thickness of 100nm by adopting a thermal evaporation method to obtain the perovskite solar cell.

Example 13

The performance of the resulting perovskite solar cell was tested and the results are shown in fig. 2-16, fig. 2 being a current density versus voltage (J-V) curve of comparative example 1 under illumination with an intensity of 100 milliwatts per square centimeter; FIG. 3 is a current density versus voltage (J-V) curve for comparative example 2 under illumination with an intensity of 100 milliwatts per square centimeter; FIG. 4 is a graph of current density versus voltage (J-V) for comparative example 3 without illumination and with illumination having an intensity of 100 milliwatts per square centimeter; FIG. 5 is a current density versus voltage (J-V) curve for example 1 under illumination with an intensity of 100 milliwatts per square centimeter; FIG. 6 is a graph of current density versus voltage (J-V) for example 2 under illumination with an intensity of 100 milliwatts per square centimeter; FIG. 7 is a current density versus voltage (J-V) curve for example 3 under illumination with an intensity of 100 milliwatts per square centimeter; FIG. 8 is a current density versus voltage (J-V) curve for example 4 under illumination with an intensity of 100 milliwatts per square centimeter; FIG. 9 is a current density versus voltage (J-V) curve for example 5 under illumination with an intensity of 100 milliwatts per square centimeter; FIG. 10 is a graph of current density versus voltage (J-V) for example 6 under illumination with an intensity of 100 milliwatts per square centimeter; FIG. 11 is a graph of current density versus voltage (J-V) for example 7 under illumination with an intensity of 100 milliwatts per square centimeter; FIG. 12 is a current density versus voltage (J-V) curve for example 8 under illumination with an intensity of 100 milliwatts per square centimeter; FIG. 13 is a current density versus voltage (J-V) curve for example 9 under illumination with an intensity of 100 milliwatts per square centimeter; FIG. 14 is a current density versus voltage (J-V) curve for example 10 under illumination with an intensity of 100 milliwatts per square centimeter; FIG. 15 is a current density versus voltage (J-V) curve for example 11 under illumination with an intensity of 100 milliwatts per square centimeter; FIG. 16 is a current density versus voltage (J-V) curve for example 12 under illumination with an intensity of 100 milliwatts per square centimeter; fig. 17 is a graph showing the change in efficiency under water and hot conditions under the conditions of comparative example 1 and example 3. The results obtained from fig. 2 to 16 are shown in table 1, and table 1 shows detailed parameters of short-circuit current density, open-circuit voltage, fill factor, and energy conversion efficiency of comparative examples 1 to 3 and examples 1 to 12.

TABLE 1 detailed parameters of short-circuit current density, open-circuit voltage, fill factor, and energy conversion efficiency for comparative examples 1-3 and examples 1-12

As can be seen from Table 1, in comparison with comparative example 1, at FAPBI₃In the perovskite system, the cross-linkable organic ligand C1 can be used as a cathode modification layer to improve the device efficiency from 19.10% to 20.37% (example 1); the efficiency was also improved from 19.10% for the comparison to 20.41% when a crosslinkable organic ligand was added as an additive to the perovskite layer (example 2); the cross-linkable organic ligand is simultaneously used as the additive in the cathode modification layer and the perovskite layer, so that the efficiency of the device can be further improved to 21.08% (example 3). This demonstrates that the introduction of a crosslinkable organic ligand can increase FAPBI₃The efficiency of the system device is mainly due to the fact that the ligand can be coordinated with cations on the surface of the uncoordinated cathode transmission layer and metal cations on the surface and grain boundaries of the perovskite, defects are passivated, and performance is improved. To verify generality, it is also in MAPbI₃Systems (comparative example 2, example 4, example 5 and example 6) and CsPbI₂Br systems (comparative example 3, example 7, example 8 and example 9) were also operated as in the above experiment and it was found that the introduction of cross-linkable organic ligands can improve the performance of different perovskite systems with versatility. For another crosslinkable organic ligand C2, at FAPBI as C1₃Similar effects are observed in the systems (example 10, example 11 and example 12). FIG. 17 is a graph showing the change in efficiency of perovskite solar cells fabricated by the methods of comparative example 1 and example 3, respectively, after exposure to humidity and heat, as can be seen from FIG. 17Now, the stability of the perovskite solar cell is greatly improved by introducing the crosslinkable organic ligand. The cross-linkable organic ligand can be anchored at the surface accessible grain boundary of the perovskite through one end of the ligand, and then cross-linked into an interpenetrating hydrophobic polymer network under the conditions of ultraviolet illumination or heating, so that the perovskite phase can be fixed, and the stability is improved. In summary, the present invention provides a method for greatly improving photoelectric conversion efficiency by introducing such bifunctional organic small molecules, and simultaneously enhancing the stability of the device.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.