Perovskite solar cell, preparation method thereof and photoelectric device

Abstract

The invention provides a perovskite solar cell, a preparation method thereof and a photoelectric device. A hole transport layer material of the perovskite solar cell comprises pyrene-containing organic molecules. The pyrene-containing organic molecule has a conjugated core of pyrene and shows excellent electronic properties at an interface, and a polycyclic aromatic hydrocarbon structure contained in the pyrene-containing organic molecule has chemical inertness and conformational rigidity, so that effective charge extraction can be performed at the interface; and passivation groups contained in the perovskite solar cell can further passivate the defects of the perovskite thin film, and the performance of the perovskite solar cell is improved.

Description

Technical Field

[0001] This invention belongs to the field of solar cell technology, and relates to a perovskite solar cell, its preparation method, and optoelectronic devices. Background Technology

[0002] Inverted perovskite solar cells (PSCs) offer superior device durability and tandem structure compatibility compared to conventional cells, demonstrating significant advantages in market integration potential. Molecular materials with hole-selective transport capabilities can significantly improve the power conversion efficiency of solar photovoltaic devices. These materials possess conjugated structures and can typically self-assemble into monolayers or multilayers at the transparent electrode and perovskite interface to ensure effective charge transport.

[0003] Molecular materials with selective hole transport capabilities typically involve heteroatom-substituted π-conjugated hydrocarbon structures. Introducing heteroatoms such as N, S, or O into the conjugated core can effectively increase electron density, ensuring efficient charge transport capabilities. However, the structural integrity of heteroatom-substituted structures is reduced, leading to potential structural instability. Providing more inert conjugated cores for molecular contacts while maintaining high electronic performance is beneficial for improving the long-term stability of PSCs.

[0004] Therefore, there is a need to provide a hole transport layer material with excellent electronic properties, so that perovskite solar cells containing the hole transport layer of this material can have good device performance. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to provide a perovskite solar cell, its fabrication method, and an optoelectronic device. This perovskite solar cell optimizes the electronic properties at the interface and passivates defects in the perovskite thin film by using pyrene-containing organic molecules, thereby improving the performance of the perovskite solar cell.

[0006] To achieve this objective, the present invention adopts the following technical solution:

[0007] In a first aspect, the present invention provides a perovskite solar cell, wherein the hole transport layer material of the perovskite solar cell includes pyrene-containing organic molecules.

[0008] The structural formula of the pyrene-containing organic molecule is:

[0009]

[0010] Wherein, A is a long-chain or short-chain group containing at least one of carboxyl, hydroxyl, amino, aldehyde, halogen atom, or borate group. The long-chain group contains two or more carbon atoms. The functional groups contained in A include at least one of carboxyl, hydroxyl, amino, aldehyde, halogen atom, or borate group. Typical but non-limiting combinations include combinations of carboxyl and hydroxyl, amino and aldehyde, halogen atom and borate group, carboxyl, amino and halogen atom, or carboxyl, hydroxyl, amino, aldehyde, halogen atom, and borate group.

[0011] This invention uses pyrene-containing organic molecules as the hole transport layer material. This material has a conjugated pyrene core and no heteroatom substitutions, exhibiting excellent electronic properties at the interface. Its polycyclic aromatic hydrocarbon structure has chemical inertness and conformational rigidity, enabling effective charge extraction at the interface. Moreover, its passivation groups can further passivate surface defects in the perovskite thin film of perovskite solar cells, thereby improving the performance of perovskite solar cells.

[0012] Preferably, the pyrene-containing organic molecule has at least one of the following formulas (I) to (V):

[0013]

[0014]

[0015] Preferably, the perovskite solar cell comprises a conductive substrate layer, a hole transport layer, a perovskite thin film, an electron transport layer, and an electrode layer stacked sequentially; or, the perovskite solar cell comprises a conductive substrate layer, an electron transport layer, a perovskite thin film, a hole transport layer, and an electrode layer stacked sequentially.

[0016] Preferably, the perovskite layer has the general formula ABX3, where A is CH3NH3. + CH(NH2)2 + Cs + or Rb + B is any combination of one or at least two of the following, where B is Pb. 2+ Sn 2+ Or Ge 2+ Any combination of one or at least two of them, X is Cl - ,Br - Or I - Any one or at least two of them.

[0017] Preferably, the thickness of the perovskite layer is 200 nm to 900 nm.

[0018] Preferably, the material of the electron transport layer includes C. 60The combination of any one or at least two of the following: [6,6]-phenyl-C61-butyrate methyl ester (PCBM), 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP), TiO2, SnO2, ZnO, or ZnO-ZnS.

[0019] Preferably, the material of the electrode layer includes any one or a combination of at least two of Au, Ag, or Al.

[0020] In a second aspect, the present invention provides a method for preparing a perovskite solar cell as described in the first aspect, the method comprising:

[0021] (1) Coating the surface of the conductive substrate with a solution containing pyrene organic molecules and annealing it by heating to self-assemble a hole transport layer.

[0022] (2) Coating the surface of the hole transport layer with a perovskite precursor solution and heat-treating it to generate a perovskite film.

[0023] (3) An electron transport layer is formed on the surface of the perovskite thin film, and then an electrode layer is formed on the surface of the electron transport layer.

[0024] Preferably, the concentration of the pyrene-containing organic molecule solution in step (1) is from 0.2 mg / mL to 1 mg / mL.

[0025] Preferably, the solvent of the pyrene-containing organic molecule solution in step (1) includes any one or a combination of at least two of ethanol, N,N-dimethylformamide (DMF), methanol, isopropanol or diethyl ether.

[0026] Preferably, the coating method in step (1) includes spin coating; the spin coating speed is 2500 rpm to 3500 rpm.

[0027] Thirdly, the present invention provides an optoelectronic device, the optoelectronic device comprising the perovskite solar cell described in the first aspect, or the perovskite solar cell prepared by the preparation method described in the second aspect.

[0028] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0029] This invention uses pyrene-containing organic molecules as the hole transport layer material. This material has a conjugated pyrene core and no heteroatom substitutions, exhibiting excellent electronic properties at the interface. Its polycyclic aromatic hydrocarbon structure has chemical inertness and conformational rigidity, enabling effective charge extraction at the interface. Moreover, its passivation groups can further passivate surface defects in the perovskite thin film of perovskite solar cells, thereby improving the performance of perovskite solar cells. Attached Figure Description

[0030] Figure 1 The fluorescence spectra of the perovskite thin films in the perovskite solar cells obtained in Example 1, Comparative Example 1, and Comparative Example 2 are shown.

[0031] Figure 2 The fluorescence lifetime spectra of the perovskite thin films in the perovskite solar cells obtained in Example 1, Comparative Example 1, and Comparative Example 2 are shown.

[0032] Figure 3 The JV curves of the perovskite thin film in the perovskite solar cells obtained in Example 1, Comparative Example 1, and Comparative Example 2 are shown. Detailed Implementation

[0033] The technical solution of the present invention will be further illustrated below through specific embodiments.

[0034] One embodiment of the present invention provides a perovskite solar cell, wherein the hole transport layer material of the perovskite solar cell includes pyrene-containing organic molecules.

[0035] The structural formula of the pyrene-containing organic molecule is:

[0036]

[0037] Wherein, A is a long-chain or short-chain group containing at least one of carboxyl, hydroxyl, amino, aldehyde, halogen atom, or borate group. The long-chain group contains two or more carbon atoms. The functional groups contained in A include at least one of carboxyl, hydroxyl, amino, aldehyde, halogen atom, or borate group. Typical but non-limiting combinations include combinations of carboxyl and hydroxyl, amino and aldehyde, halogen atom and borate group, carboxyl, amino and halogen atom, or carboxyl, hydroxyl, amino, aldehyde, halogen atom, and borate group.

[0038] This invention uses pyrene-containing organic molecules as the hole transport layer material. This material has a conjugated pyrene core and no heteroatom substitutions, exhibiting excellent electronic properties at the interface. Its polycyclic aromatic hydrocarbon structure has chemical inertness and conformational rigidity, enabling effective charge extraction at the interface. Moreover, its passivation groups can further passivate surface defects in the perovskite thin film of perovskite solar cells, thereby improving the performance of perovskite solar cells.

[0039] For example, the preparation method of the pyrene-containing organic molecule of the present invention includes the following steps:

[0040] (1) In a protective atmosphere, a pyrene-containing organic molecule precursor, aluminum trichloride and dichloromethane are mixed and cooled to below 0°C, and then mixed with bromoacetyl bromide; the resulting mixture is heated to room temperature and reacted under stirring conditions, diluted with dichloromethane and washed with water; the organic layer is collected, dried and then subjected to rotary evaporation under reduced pressure to remove dichloromethane, and then purified by chromatography to obtain the first intermediate product.

[0041] The structural formula of the pyrene-containing organic molecule precursor is:

[0042]

[0043] Wherein, A is a long-chain group or a short-chain group containing at least one of carboxyl, hydroxyl, amino, aldehyde, halogen atom or boric acid group.

[0044] The structural formula of the first intermediate product is as follows:

[0045]

[0046] (2) Under a protective atmosphere, the first intermediate was mixed with trichloroacetic acid, and triethylsilane was added dropwise at a temperature below 0°C. The mixture was then heated to room temperature and stirred overnight. The solution was then diluted with dichloromethane and washed with a saturated sodium bicarbonate aqueous solution. The organic layer was collected, dried, and the dichloromethane was removed by rotary evaporation under reduced pressure. The product was then purified by chromatography to obtain the second intermediate. The structural formula of the second intermediate is:

[0047]

[0048] (3) Under a protective atmosphere, the second intermediate product and triethyl phosphite were mixed and reacted at a raised temperature. The reactants were cooled to room temperature, and the organic solvent was removed by rotary evaporation. The crude product was purified by chromatography to obtain the third intermediate product. The structural formula of the third intermediate product is as follows:

[0049]

[0050] (4) Under a protective atmosphere, the third intermediate product and 1,4-dioxane are mixed and trimethylthiosilane is gradually mixed in. The mixture is heated to room temperature and stirred to react. The dissolved product is removed by rotary evaporation under reduced pressure. The obtained intermediate is dissolved in methanol and distilled water is added dropwise until the solution is clear. The reaction is continued by stirring. The obtained solid is washed to obtain the pyrene-containing organic molecule.

[0051] In this invention, the protective atmosphere used in steps (1) to (4) includes nitrogen and / or an inert gas. The inert gas includes any one or a combination of at least two of helium, neon, or argon.

[0052] In some embodiments, the pyrene-containing organic molecule has at least one of the following formulas (I) to (V):

[0053]

[0054] In some embodiments, the perovskite solar cell includes a conductive substrate layer, a hole transport layer, a perovskite thin film, an electron transport layer, and an electrode layer stacked sequentially.

[0055] In some embodiments, the perovskite solar cell includes a conductive substrate layer, an electron transport layer, a perovskite thin film, a hole transport layer, and an electrode layer stacked sequentially.

[0056] In some embodiments, the conductive substrate layer is made of fluorine-doped tin oxide (FTO) or indium tin oxide (ITO).

[0057] In some embodiments, the thickness of the conductive substrate layer is from 80 nm to 200 nm, for example, it can be 80 nm, 100 nm, 120 nm, 150 nm, 180 nm or 200 nm, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0058] In some embodiments, the perovskite layer is made of the general formula ABX3, where A is CH3NH3. + (MA), CH(NH2)2 + (FA), Cs + or Rb + Any combination of one or at least two of the above, typical but non-limiting combinations include combinations of MA and FA, MA and Cs. + The combination of MA and Rb + The combination of Fa and Cs + With Rb + Combinations, or MA, FA, Cs + With Rb + The combination; B is Pb 2+ Sn 2+ Or Ge 2+ Any one or at least two of the following, typical but non-limiting combinations include Pb 2+ With Sn 2+ The combination of Sn 2+ With Ge 2+ The combination of Pb 2+ With Ge 2+ The combination of, or Pb 2+ Sn 2+ With Ge 2+ Combination of X; X is Cl - ,Br - Or I- Any one or at least two of the above, typical but non-limiting combinations include Cl - With Br - The combination, Br - with I - The combination, Cl - with I - Combinations, or Cl - ,Br - with I - The combination of .

[0059] In some embodiments, the thickness of the perovskite layer is 200 nm to 900 nm, for example, it can be 200 nm, 300 nm, 400 nm, 500 nm, 600 nm, 800 nm or 900 nm, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0060] In some embodiments, the material of the electron transport layer includes C. 60 [6,6]-phenyl-C61-butyrate methyl ester (PCBM), 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP), TiO2, SnO2, ZnO, or ZnO-ZnS, or combinations of at least two of these, with typical but non-limiting combinations including C 60 Combinations with PCBM, PCBM and BCP, BCP, TiO2 and SnO2, TiO2, SnO2 and ZnO, or C 60 Combinations of PCBM, BCP, TiO2, SnO2, ZnO and ZnO-ZnS.

[0061] In some embodiments, the thickness of the electron transport layer is from 10 nm to 30 nm, for example, it can be 10 nm, 15 nm, 20 nm, 25 nm or 30 nm, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0062] In some embodiments, the material of the electrode layer includes any one or a combination of at least two of Au, Ag, or Al. Typical but non-limiting combinations include combinations of Au and Ag, Ag and Al, Au and Al, or Au, Ag, and Al.

[0063] In some embodiments, the thickness of the electrode layer is 100-150 nm, for example, it can be 100 nm, 110 nm, 120 nm, 140 nm or 150 nm, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0064] An embodiment of the present invention provides a method for fabricating a perovskite solar cell according to any embodiment, the method comprising:

[0065] (1) Coating the surface of the conductive substrate with a solution containing pyrene organic molecules and annealing it by heating to self-assemble a hole transport layer.

[0066] (2) Coating the surface of the hole transport layer with a perovskite precursor solution and heat-treating it to generate a perovskite film.

[0067] (3) An electron transport layer is formed on the surface of the perovskite thin film, and then an electrode layer is formed on the surface of the electron transport layer.

[0068] In some embodiments, the concentration of the pyrene-containing organic molecule solution in step (1) is from 0.2 mg / mL to 1 mg / mL, for example, it can be 0.2 mg / mL, 0.3 mg / mL, 0.4 mg / mL, 0.5 mg / mL, 0.6 mg / mL, 0.8 mg / mL or 1 mg / mL, but is not limited to the listed values, and other values ​​not listed in the range are equally applicable.

[0069] In this invention, the concentration of the pyrene-containing organic molecule solution is related to the thickness of the final hole transport layer; the higher the concentration, the thicker the layer. This invention controls the concentration of the pyrene-containing organic molecule solution to be between 0.2 mg / mL and 1 mg / mL to obtain a hole transport layer of suitable thickness.

[0070] In some embodiments, the solvent of the pyrene-containing organic molecule solution in step (1) includes any one or a combination of at least two of ethanol, N,N-dimethylformamide (DMF), methanol, isopropanol, or diethyl ether. Typical but non-limiting combinations include combinations of ethanol and DMF, methanol and isopropanol, methanol and diethyl ether, DMF, methanol, isopropanol, and diethyl ether, or ethanol, DMF, methanol, isopropanol, and diethyl ether.

[0071] In some embodiments, the coating method in step (1) includes spin coating; the spin coating speed is 2500 rpm to 3500 rpm, for example, it can be 2500 rpm, 2800 rpm, 3000 rpm, 3200 rpm or 3500 rpm, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0072] In some embodiments, the solvent in the perovskite precursor solution in step (2) includes any one or a combination of at least two of N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), N-methyl-2-pyrrolidone (NMP), γ-butyrolactone (GBL), 1,3-dimethyl-2-imidazolinone (DMI), dimethylacetamide (DMAC), N,N-dimethylpropenylurea (DMPU), acetonitrile (CAN), or 2-mercaptoethanol (2-ME).

[0073] An embodiment of the present invention provides an optoelectronic device, the optoelectronic device comprising a perovskite solar cell as described in any embodiment, or a perovskite solar cell prepared by any of the preparation methods described in any embodiment.

[0074] Example 1

[0075] This embodiment provides a perovskite solar cell, which includes a conductive substrate layer, a hole transport layer, a perovskite thin film, an electron transport layer, and an electrode layer stacked sequentially.

[0076] The hole transport layer material is a pyrene-containing organic molecule, and its structural formula is:

[0077]

[0078] The method for fabricating perovskite solar cells provided in this embodiment includes the following steps:

[0079] (I) Ultrasonic cleaning of the 2cm×2.5cm conductive substrate (ITO) and drying with nitrogen.

[0080] (II) Dissolve the pyrene-containing organic molecule in ethanol to prepare a pyrene-containing organic molecule solution with a concentration of 0.5 mg / mL. Then spin-coat 100 μL of the pyrene-containing organic molecule solution onto the conductive substrate at a speed of 3000 rpm for 30 s. After spin-coating, anneal at 100 °C for 10 min to self-assemble the hole transport layer.

[0081] (III) A perovskite precursor solution was spin-coated on the surface of the hole transport layer at a speed of 5000 rpm for 50 s. At the 35th s, 200 μL of chlorobenzene was added dropwise, and the film was heat-treated at a temperature of 120 °C for 15 min to generate a perovskite film with a thickness of 450 nm.

[0082] The perovskite precursor solution consisted of a well-mixed mixture of 108.33 mg CsI, 1218.34 mg FAI, 132.5 mg MAI, 4033.76 mg PbI2, 83.27 mg MACl, 4200 μL DMF, and 840 μL DMSO.

[0083] The perovskite thin film is made of Cs. 0.05 MA 0.1 FA 0.85 PbI3.

[0084] (IV) An electron transport layer C with a thickness of 25 nm was deposited on the surface of the perovskite thin film by vacuum evaporation. 60 Vacuum evaporation at a vacuum degree of 5×10 -4 The deposition was carried out under Pa conditions at a deposition rate of [value missing].

[0085] (V) A 5 nm thick electron transport layer BCP is deposited on the surface of the electron transport layer by vacuum evaporation at a vacuum degree of 5 × 10⁻⁶. -4 The deposition was carried out under Pa conditions at a deposition rate of [value missing].

[0086] (VI) An Ag electrode layer with a thickness of 120 nm was formed on the surface of the electron transport layer BCP by thermal evaporation at a temperature of 5 × 10⁻⁶ nm. -4 The experiment was conducted at a rate of Pa.

[0087] Example 2

[0088] This embodiment provides a perovskite solar cell, which is the same as that in Example 1 except that the structure containing pyrene organic molecules is different from that in Example 1.

[0089] The structural formula of the pyrene organic molecule in this embodiment is:

[0090]

[0091] Example 3

[0092] This embodiment provides a perovskite solar cell, which is the same as that in Example 1 except that the structure containing pyrene organic molecules is different from that in Example 1.

[0093] The structural formula of the pyrene organic molecule in this embodiment is:

[0094]

[0095] Example 4

[0096] This embodiment provides a perovskite solar cell, which is the same as that in Example 1 except that the structure containing pyrene organic molecules is different from that in Example 1.

[0097] The structural formula of the pyrene organic molecule in this embodiment is:

[0098]

[0099] Example 5

[0100] This embodiment provides a perovskite solar cell, which is the same as that in Example 1 except that the structure containing pyrene organic molecules is different from that in Example 1.

[0101] The structural formula of the pyrene organic molecule in this embodiment is:

[0102]

[0103] Example 6

[0104] This embodiment provides a perovskite solar cell, which is the same as in Example 1 except that the concentration of the pyrene-containing organic molecule solution used in the preparation of the perovskite solar cell is 0.2 mg / mL.

[0105] Example 7

[0106] This embodiment provides a perovskite solar cell, which is the same as in Example 1 except that the concentration of the pyrene-containing organic molecule solution used in the preparation of the perovskite solar cell is 1 mg / mL.

[0107] Example 8

[0108] This embodiment provides a perovskite solar cell, which is the same as in Example 1 except that the concentration of the pyrene-containing organic molecule solution used in the preparation of the perovskite solar cell is 0.1 mg / mL.

[0109] Example 9

[0110] This embodiment provides a perovskite solar cell, which is the same as in Example 1 except that the concentration of the pyrene-containing organic molecule solution used in the preparation of the perovskite solar cell is 1.2 mg / mL.

[0111] Comparative Example 1

[0112] This comparative example provides a perovskite solar cell, which includes a conductive substrate layer, a hole transport layer, a perovskite thin film, an electron transport layer, and an electrode layer stacked sequentially.

[0113] The fabrication method of the perovskite solar cell provided in this comparative example includes the following steps:

[0114] (I) Ultrasonic cleaning of the 2cm×2.5cm conductive substrate (ITO) and drying with nitrogen.

[0115] (II) Dissolve [2-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl]phosphonic acid in ethanol to prepare an organic molecular solution with a concentration of 0.5 mg / mL. Then spin-coat 100 μL of the organic molecular solution onto the conductive substrate at a speed of 3000 rpm for 30 s. After spin-coating, anneal at 100 °C for 10 min to form a hole transport layer.

[0116] (III) A perovskite precursor solution was spin-coated on the surface of the hole transport layer at a speed of 5000 rpm for 50 s. At the 35th s, 200 μL of chlorobenzene was added dropwise, and the film was heat-treated at a temperature of 120 °C for 15 min to generate a perovskite film with a thickness of 450 nm.

[0117] The perovskite precursor solution consisted of a well-mixed mixture of 108.33 mg CsI, 1218.34 mg FAI, 132.5 mg MAI, 4033.76 mg PbI2, 83.27 mg MACl, 4200 μL DMF, and 840 μL DMSO.

[0118] The perovskite thin film is made of Cs. 0.05 MA 0.1 FA 0.85 PbI3.

[0119] (IV) An electron transport layer C with a thickness of 25 nm was deposited on the surface of the perovskite thin film by vacuum evaporation. 60 Vacuum evaporation at a vacuum degree of 5×10 -4 The deposition was carried out under Pa conditions at a deposition rate of [value missing].

[0120] (V) A 5 nm thick electron transport layer BCP is deposited on the surface of the electron transport layer by vacuum evaporation at a vacuum degree of 5 × 10⁻⁶. -4 The deposition was carried out under Pa conditions at a deposition rate of [value missing].

[0121] (VI) An Ag electrode layer with a thickness of 120 nm was formed on the surface of the electron transport layer BCP by thermal evaporation at a temperature of 5 × 10⁻⁶ nm. -4 The experiment was conducted at a rate of Pa.

[0122] Comparative Example 2

[0123] This comparative example provides a perovskite solar cell, which is identical to Example 1 except for the structural formula containing pyrene organic molecules.

[0124] The structural formula of the pyrene organic molecule in this comparative example is:

[0125]

[0126] Performance Characterization

[0127] In this invention, Figure 1 The fluorescence spectra of the perovskite thin films in the perovskite solar cells obtained in Example 1, Comparative Example 1, and Comparative Example 2 are shown. Figure 1 It is known that when the hole transport layer is a commonly used self-assembled molecular layer, the perovskite film exhibits a high photoluminescence (PL) intensity. The use of pyrene-containing organic molecules significantly enhances the PL quenching at the interface between the perovskite film and the hole transport layer. Quenching is considered to be the transfer of hole charge from the perovskite layer to the conductive substrate, thereby reducing radiative relaxation from the excited state to the ground state. Simultaneously, due to… Figure 2 It can be seen that the lifetime of perovskite films based on pyrene-containing organic molecules is reduced, indicating that the introduction of pyrene-containing organic molecules effectively promotes hole separation at the interface between the perovskite layer and the conductive substrate layer.

[0128] Figure 3 The JV curves of the perovskite thin film in the perovskite solar cells obtained in Example 1, Comparative Example 1, and Comparative Example 2 are shown.

[0129] The open-circuit voltage (Voc), short-circuit current density (Jsc), fill factor (FF), and power conversion efficiency (PCE) of the perovskite solar cells obtained in the above embodiments and comparative examples were tested. The results are shown in Table 1. The test conditions were as follows: a solar energy simulation test device was used, and a 500W xenon lamp solar spectrum simulator was used as the light source, under a solar intensity (AM 1.5G: 100mW / cm²). 2 The test was conducted under the following conditions.

[0130] Table 1

[0131]

[0132]

[0133] As shown in Table 1, the open-circuit voltage, short-circuit current density, fill factor, and photoelectric conversion efficiency of the perovskite solar cell based on pyrene-containing organic molecules are significantly improved. One reason for the improved cell performance is that the anchoring groups in the pyrene-containing organic molecules are anchored to the surface of the conductive substrate layer, forming strong and stable covalent bonds, achieving selective contact to reduce surface defects and promote charge transfer. The large number of charge carriers accumulated at the interface between the conductive substrate layer and the perovskite seeding layer are highly selectively extracted by the hole transport layer, reducing non-radiative recombination at the interface and thus lowering the device efficiency. A comparison between Comparative Example 2 and Example 1 shows that the passivating groups in the pyrene-containing organic molecules can further passivate surface defects in the perovskite thin film, improving the performance of the perovskite solar cell.

[0134] A comparison of Example 8 and Example 1 shows that when the concentration of the pyrene-containing organic molecule solution is low, the risk of direct contact between the perovskite film and the conductive substrate increases, leading to a large number of non-radiative recombinations on the surface of the perovskite film and a decrease in photoelectric conversion efficiency. A comparison of Example 9 and Example 1 shows that a higher concentration of the pyrene-containing organic molecule solution will hinder hole transport to a certain extent and affect battery efficiency. Therefore, as a preferred technical solution, the concentration of the pyrene-containing organic molecule solution needs to be between 0.2 mg / mL and 1 mg / mL.

[0135] In summary, this invention uses pyrene-containing organic molecules as the hole transport layer material. This material has a conjugated pyrene core and no heteroatom substitutions, exhibiting excellent electronic properties at the interface. Its polycyclic aromatic hydrocarbon structure is chemically inert and conformationally rigid, enabling effective charge extraction at the interface. Furthermore, its passivating groups can further passivate surface defects in the perovskite thin film of perovskite solar cells, thereby improving the performance of perovskite solar cells.

[0136] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A perovskite solar cell, characterized in that, The hole transport layer material of the perovskite solar cell includes pyrene-containing organic molecules; The structural formula of the pyrene-containing organic molecule is: Wherein, A is a long-chain group or a short-chain group containing at least one of carboxyl, hydroxyl, amino, aldehyde, halogen atom or boric acid group.

2. The perovskite solar cell according to claim 1, characterized in that, The pyrene-containing organic molecule has at least one of the following structural formulas (I) to (V):

3. The perovskite solar cell according to claim 1 or 2, characterized in that, The perovskite solar cell comprises a conductive substrate layer, a hole transport layer, a perovskite thin film, an electron transport layer, and an electrode layer stacked sequentially. Alternatively, the perovskite solar cell may include a conductive substrate layer, an electron transport layer, a perovskite thin film, a hole transport layer, and an electrode layer stacked sequentially.

4. The perovskite solar cell according to claim 3, characterized in that, The general formula for the perovskite layer is ABX3, where A is CH3NH3. + CH(NH2)2 + Cs + or Rb + B is any combination of one or at least two of the following, where B is Pb. 2+ Sn 2+ Or Ge 2+ Any combination of one or at least two of them, X is Cl - ,Br - or I - Any one or at least two of them; And / or, the thickness of the perovskite layer is 200 nm to 900 nm.

5. The perovskite solar cell according to claim 3, characterized in that, The material of the electron transport layer includes C. 60 The combination of any one or at least two of the following: [6,6]-phenyl-C61-butyrate, 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline, TiO2, SnO2, ZnO, or ZnO-ZnS.

6. The perovskite solar cell according to claim 3, characterized in that, The electrode layer is made of any one or a combination of at least two of Au, Ag, or Al.

7. A method for preparing a perovskite solar cell according to any one of claims 1 to 6, characterized in that, The preparation method includes: (1) Coating the surface of the conductive substrate with a solution containing pyrene organic molecules and annealing it by heating to self-assemble a hole transport layer; (2) Coating the surface of the hole transport layer with a perovskite precursor solution and heat-treating it to generate a perovskite film. (3) An electron transport layer is formed on the surface of the perovskite thin film, and then an electrode layer is formed on the surface of the electron transport layer.

8. The preparation method according to claim 7, characterized in that, The concentration of the pyrene-containing organic molecule solution in step (1) is from 0.2 mg / mL to 1 mg / mL; And / or, the solvent of the pyrene-containing organic molecule solution in step (1) includes any one or a combination of at least two of ethanol, DMF, methanol, isopropanol or diethyl ether.

9. The preparation method according to claim 7, characterized in that, The coating method described in step (1) includes spin coating; The spin coating speed is 2500 rpm to 3500 rpm.

10. An optoelectronic device, characterized in that, The optoelectronic device includes the perovskite solar cell according to any one of claims 1 to 6, or the perovskite solar cell prepared by the preparation method according to any one of claims 7 to 9.

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