Self-assembled monomolecular layer hole transport material of indeno-carbazole derivative and preparation method and application of self-assembled monomolecular layer hole transport material

Abstract

The invention provides a self-assembled monomolecular layer hole transport material of an indenocarbazole derivative and a preparation method and application thereof, the hole transport material has a structure shown in a formula I. The self-assembled monomolecular layer hole transport material is simple in structure, high in hole transport property, strong in interface passivation ability and high in thermal stability, and can be applied to the field of hole transport. Indenocarbazole with a rigid conjugate large plane is used as a parent nucleus, so that molecular accumulation can be improved, and the hole transport performance of the material can be improved. By taking a phosphate group as a tail end, single-molecule self-assembly can be realized, a perovskite interface can be passivated, the energy loss at the interface is reduced, and the battery performance is improved. When the synthesized material is used as a hole transport layer of an inverted perovskite solar cell, gt can be obtained without doping; and meanwhile, the service life of the perovskite solar cell is greatly prolonged, the stability of the perovskite solar cell is greatly improved, and industrialization of the perovskite solar cell is expected to be achieved.

Description

Technical Field

[0001] This invention belongs to the field of solar energy technology, and relates to a self-assembled monolayer hole transport material of indenocarbazole derivative, its preparation method and application. Background Technology

[0002] As a next-generation photovoltaic technology, perovskite solar cells (PSCs) have advantages such as simple fabrication processes, easily modulated materials, and low cost. The latest certified efficiency has reached 26.2% (National Renewable Energy Laboratory, NREL, 2023). Perovskite solar cells have two main structural types: a forward-facing nip structure and a reverse-facing pin structure. Compared to… structure, This structure is better suited for fabricating large-area, tandem solar cells because it can utilize low-temperature processes and a wider variety of carrier extraction layers, giving it greater commercial potential. However, The structure also faces a challenge: how to improve the interface quality and stability between the hole-selective layer and the perovskite. Currently, commonly used hole transport materials (HTMs) for inverting devices include inorganic materials such as nickel oxide (NiOx) and organic polymer materials such as poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA). Among them, nickel oxide has energy level mismatches and defect states with the perovskite, leading to voltage loss and interface degradation; PTAA is expensive, has unstable batch production, and low film wettability, all of which limit further improvement in device performance. Therefore, developing high-performance, novel hole transport materials for inverting devices is crucial to device performance. Self-assembled monolayers (SAMs) as hole transport materials have the characteristics of simple structure and flexible design, and can effectively adjust interface energy levels and reduce defect states based on molecular engineering. At the same time, these materials also exhibit unique advantages such as low parasitic absorption, low material consumption, compatibility with tandem perovskite solar cells, and simplified fabrication of large-area devices, making them a popular choice for fabricating high-efficiency perovskite solar cells.

[0003] Hole transport materials (HTMs) are an important component of power cell batteries (PSCs) and play a crucial role in battery efficiency and stability. Poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA) is currently the most commonly used HTM in high-efficiency inverted PSCs, but several problems with PTAA itself seriously hinder the industrialization of inverted PSCs: First, the price of PTAA is as high as $1980 / g, dozens of times that of gold, preventing its large-scale application; second, PTAA itself has a low hole mobility (~10). 5cm 2 V -1 s -1 ), lithium bis-trifluoromethanesulfonimide (Li-TFSI), 2,3,5,6-tetrafluoro-7,7',8,8'-tetracyanoquinodimethane (F4TCNQ) and other dopants need to be added to improve the hole transport performance, however, these water-absorbing dopants will cause the decomposition of perovskite, greatly affecting the long-term stability of the battery; finally, as a kind of polymer, the molecular weight and photovoltaic performance of PTAA will change with the synthesis batch, which is not conducive to industrial application.

[0004] Therefore, developing a new type of SAM material with simple structure, low cost and excellent performance is a key problem to be solved to promote the industrialization process of PSCs. SUMMARY

[0005] In view of the deficiencies of the prior art, the purpose of the present application is to provide a self-assembled monolayer hole transport material of indenocarbazole derivative and its preparation method and application.

[0006] To achieve the purpose of the present application, the following technical solutions are adopted:

[0007] On the one hand, the present application provides a self-assembled monolayer hole transport material of indenocarbazole derivative, which has the following structure shown in formula I:

[0008] ;

[0009] Wherein R1 is selected from the group of extended conjugated groups, selected from the following groups:

[0010]

[0011] Wherein the asterisk represents the connection site of the group.

[0012] Wherein L is a connecting group, selected from any one of L1~L3:

[0013] ;

[0014] Wherein represents the connection site of the connecting group.

[0015] Wherein the asterisk represents the connection site of the group.

[0016] The self-assembled monolayer hole transport material of the present application has simple structure, high hole transport property, strong interface passivation ability, high thermal stability, and is suitable for large-scale application, and the indenocarbazole with rigid conjugated large plane as the mother nucleus can improve the molecular packing and improve the hole transport performance of the material. The terminal phosphoric acid group can realize single molecule self-assembly and passivation of perovskite interface, reduce the energy loss at the interface, and improve the battery performance. When the synthesized material is used as the hole transport layer of the inverted perovskite solar cell, a photoelectric conversion efficiency of >24% can be obtained without doping, and the service life and stability of the perovskite solar cell are greatly improved, which is expected to help the perovskite solar cell to realize industrialization.

[0017] Preferably, R1 is selected from G1, and L is selected from L1, L2 or L3.

[0018] Preferably, R1 is selected from G2, G3, G4, G5, G6, G7, G8, G9 or G10, and L is selected from L1.

[0019] As a preferred technical scheme of the present application, the self-assembled monolayer hole transport material of the indenocarbazole derivative is selected from any one of the following compounds A1-A12:

[0020] ;

[0021] In another aspect, the present application provides a preparation method of the self-assembled monolayer hole transport material of the indenocarbazole derivative as described above, which comprises the following steps:

[0022] (1) Synthesis of the self-assembled monolayer hole transport material of L1:

[0023] S1-1, the compound of formula II is reacted with the compound of formula III to obtain the compound of formula IV, and the reaction formula is as follows:

[0024] ;

[0025] S1-2, the compound of formula IV is subjected to hydrolysis reaction to obtain the self-assembled monolayer hole transport material of the indenocarbazole derivative of formula I, and the reaction formula is as follows:

[0026] ;

[0027] (2) Synthesis of the self-assembled monolayer hole transport material of L2:

[0028] S2-1, the compound of formula B is reacted with the compound of formula C to obtain the compound of formula D, and the reaction formula is as follows:

[0029]

[0030] S2-2, the compound of formula D is reacted with a compound of formula E to obtain a compound of formula F, as shown in the following reaction formula:

[0031] ;

[0032] S2-3, the compound of formula E is subjected to a hydrogenation reduction reaction to obtain a compound of formula E, as shown in the following reaction formula:

[0033] ;

[0034] S2-4, the compound of formula H is subjected to a hydrolysis reaction to obtain a self-assembled monolayer hole transport material based on indenocarbazole derivative of formula I, as shown in the following reaction formula:

[0035] ;

[0036] (3) Synthesis of the self-assembled monolayer hole transport material of L3 of L:

[0037] S3-1, the compound of formula b is reacted with a compound of formula c to obtain a compound of formula d, as shown in the following reaction formula:

[0038] ;

[0039] S3-2, the compound of formula d is reacted with a compound of formula e to obtain a compound of formula f, as shown in the following reaction formula:

[0040] ;

[0041] S3-3, the compound of formula f is subjected to a hydrolysis reaction to obtain a self-assembled monolayer hole transport material based on indenocarbazole derivative of formula I, as shown in the following reaction formula:

[0042] ;

[0043] wherein R2 and R3 are independently selected from C1-C5 (e.g., C1, C2, C3, C4, or C5) alkyl, and X is selected from halogen.

[0044] In the present application, R2 and R3 are independently selected from methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, n-pentyl, and the like. X is selected from F, Cl, Br, or I, preferably Br.

[0045] Preferably, the molar ratio of the compound of formula II to the compound of formula III in step S1-1 is 1:1-1.5, such as 1:1, 1:1.1, 1:1.2, 1:1.3, 1:1.4, or 1:1.5.

[0046] Preferably, the reaction of step S1-1 is carried out in the presence of a catalyst selected from cuprous iodide.

[0047] Preferably, the reaction of step S1-1 is carried out in the presence of a basic substance selected from potassium carbonate and / or sodium carbonate.

[0048] Preferably, the reaction of step S1-1 is carried out in an organic solvent selected from N,N'-dimethylacetamide.

[0049] Preferably, the reaction of step S1-1 is carried out at a temperature of 160-180 °C, such as 160 °C, 165 °C, 170 °C, 175 °C or 180 °C, for a reaction time of 20-24 h, such as 20 h, 21 h, 22 h, 23 h or 24 h.

[0050] Preferably, the hydrolysis reaction of step S1-2 is carried out in the presence of trimethylsilyl bromide.

[0051] Preferably, the molar ratio of trimethylsilyl bromide to the compound of formula IV is 2:1-4:1, such as 2:1, 2.5:1, 3:1, 3.5:1 or 4:1.

[0052] Preferably, the hydrolysis reaction of step S1-2 is carried out in an organic solvent selected from dichloromethane and / or trichloromethane.

[0053] Preferably, the hydrolysis reaction of step S1-2 is carried out at room temperature (15-30 °C, such as 15 °C, 20 °C, 25 °C or 30 °C) for a reaction time of 12-18 hours (such as 12 hours, 13 hours, 15 hours, 17 hours or 18 hours).

[0054] Preferably, the molar ratio of the compound of formula B to the compound of formula C of step S2-1 is 1:5-1:7, such as 1:5, 1:5.5, 1:6, 1:6.5 or 1:7.

[0055] Preferably, the reaction of step S2-1 is carried out in the presence of a basic substance selected from potassium phosphate or sodium phosphate.

[0056] Preferably, the reaction of step S2-1 is carried out in an organic solvent selected from N-methylpyrrolidone.

[0057] Preferably, the reaction of step S2-1 is carried out at a temperature of 160-180 °C, such as 160 °C, 165 °C, 170 °C, 175 °C or 180 °C, for a reaction time of 40-48 h, such as 40 h, 42 h, 44 h, 46 h or 48 h.

[0058] Preferably, the reaction of step S2-1 is carried out under inert gas protection.

[0059] Preferably, the molar ratio of the compound of formula D to the compound of formula E in step S2-2 is 1:3~1:4 (e.g. 1:3, 1:3.2, 1:3.5, 1:3.7 or 1:4, etc.).

[0060] Preferably, the reaction of step S2-2 is carried out in the presence of a basic substance, which is triethylamine.

[0061] Preferably, the reaction of step S2-2 is carried out in the presence of a ligand, which is selected from tris(o-tolyl)phosphine.

[0062] Preferably, the reaction of step S2-2 is carried out in the presence of a catalyst, which is palladium acetate.

[0063] Preferably, the temperature of the reaction of step S2-2 is 100~120℃ (e.g. 100℃, 105℃, 110℃, 115℃ or 120℃, etc.) and the reaction time is 12~20 h (e.g. 12 h, 14 h, 16 h, 18 h or 20 h, etc.).

[0064] Preferably, the reducing agent of the hydrogenation reduction reaction of step S2-3 is sodium borohydride.

[0065] Preferably, the hydrogenation reduction reaction of step S2-3 is carried out in the presence of a catalyst, which is cobalt chloride.

[0066] Preferably, the hydrogenation reduction reaction of step S2-3 is carried out in an organic solvent, which is methanol.

[0067] Preferably, the hydrogenation reduction reaction of step S2-3 is carried out under nitrogen protection.

[0068] Preferably, the hydrogenation reduction reaction of step S2-3 is carried out at room temperature and the reaction time is 1~2 hours (e.g. 1 hour, 1.2 hours, 1.5 hours, 1.7 hours or 2 hours, etc.).

[0069] Preferably, the hydrolysis reaction of step S2-4 is carried out in the presence of trimethylsilyl bromide.

[0070] Preferably, the molar ratio of the trimethylsilyl bromide to the compound of formula H is 2:1~4:1 (e.g. 2:1, 2.5:1, 3:1, 3.5:1 or 4:1).

[0071] Preferably, the hydrolysis reaction of step S2-4 is carried out in an organic solvent, which is selected from 1,4-dioxane.

[0072] Preferably, the hydrolysis reaction of step S2-4 is carried out at room temperature, and the reaction time is 12-18 hours (for example, 12 hours, 13 hours, 15 hours, 17 hours, or 18 hours).

[0073] Preferably, the molar ratio of the compound of formula b to the compound of formula c in step S3-1 is 1:3.5-1:5 (for example, 1:3.5, 1:3.7, 1:3.9, 1:4.1, 1:4.3, 1:4.5, 1:4.7, 1:4.9, or 1:5, etc.).

[0074] Preferably, the reaction of step S3-1 is carried out in the presence of a basic substance selected from potassium carbonate or sodium carbonate.

[0075] Preferably, the reaction of step S3-1 is carried out in the presence of a catalyst selected from cuprous iodide.

[0076] Preferably, the reaction of step S3-1 is carried out in an organic solvent selected from N,N-dimethylacetamide.

[0077] Preferably, the temperature of the reaction of step S3-1 is 160-200°C (for example, 160°C, 170°C, 180°C, 190°C, or 200°C, etc.), and the reaction time is 20-30 hours (for example, 20 hours, 21 hours, 22 hours, 23 hours, 24 hours, 25 hours, 26 hours, 27 hours, 28 hours, or 30 hours, etc.).

[0078] Preferably, the molar ratio of the compound of formula d to the compound of formula e in step S3-2 is 1:1.5-1:3 (for example, 1:1.5, 1:1.7, 1:1.9, 1:2.1, 1:2.3, 1:2.5, 1:2.7, 1:2.9, or 1:3, etc.).

[0079] Preferably, the reaction of step S3-2 is carried out in the presence of a catalyst which is palladium acetate.

[0080] Preferably, the reaction of step S3-2 is carried out in the presence of a ligand selected from 1,1'-bis(diphenylphosphino)ferrocene.

[0081] Preferably, the reaction of step S3-2 is carried out in the presence of a basic substance which is potassium acetate.

[0082] Preferably, the temperature of the reaction of step S3-2 is 100-120°C (for example, 100°C, 105°C, 110°C, 115°C, or 120°C, etc.), and the reaction time is 20-30 hours (for example, 20 hours, 22 hours, 25 hours, 27 hours, or 30 hours, etc.).

[0083] Preferably, the reaction in step S3-2 is carried out under nitrogen protection.

[0084] Preferably, the hydrolysis reaction in step S3-3 is carried out in the presence of trimethylsilyl bromide.

[0085] Preferably, the molar ratio of trimethylsilyl bromide to the compound of formula f is 2:1 to 4:1, for example 2:1, 2.5:1, 3:1, 3.5:1 or 4:1.

[0086] Preferably, the hydrolysis reaction in step S1-2 is carried out in an organic solvent selected from dichloromethane and / or trichloromethane.

[0087] Preferably, the hydrolysis reaction in step S1-2 is carried out at room temperature, and the reaction time is 12 to 18 hours (for example 12 hours, 13 hours, 15 hours, 17 hours or 18 hours).

[0088] In another aspect, the present application provides a perovskite solar cell comprising a self-assembled monolayer, wherein the self-assembled monolayer comprises the self-assembled monolayer hole transport material based on indenocarbazole derivative as described above.

[0089] Preferably, the perovskite solar cell is a trans perovskite solar cell.

[0090] Preferably, the perovskite solar cell comprises, in sequence, a cathode layer, an electron transport layer, a passivation layer, a perovskite light absorbing layer, a self-assembled monolayer, a hole transport layer, and an anode layer.

[0091] Preferably, the self-assembled monolayer is obtained by coating a solution of the self-assembled monolayer hole transport material based on indenocarbazole derivative as described above onto the surface of the hole transport layer, and performing thermal annealing.

[0092] Preferably, the thermal annealing is performed at a temperature of 80 to 120°C, for example 80°C, 90°C, 100°C, 110°C or 120°C, and for a time of 5 to 20 minutes, for example 5 minutes, 10 minutes, 15 minutes or 20 minutes.

[0093] In the present application, the perovskite light absorbing layer is prepared by coating (for example spin coating) a perovskite solution onto the surface of the self-assembled monolayer.

[0094] In the present application, the coating can be performed by slot coating or spin coating.

[0095] Compared with the prior art, the present application has the following beneficial effects:

[0096] The self-assembled monolayer hole transport material has simple structure, high hole transport property, strong interface passivation ability, high thermal stability, and is suitable for large-scale application, and the indenocarbazole with rigid conjugated large plane as the mother nucleus can improve the molecular accumulation and improve the hole transport performance of the material. The phosphoric acid group as the terminal can realize the self-assembly of single molecule and passivation of perovskite interface, reduce the energy loss at the interface, and improve the battery performance. When the synthesized material is used as the hole transport layer of the inverted perovskite solar cell, the photoelectric conversion efficiency of more than 24% can be obtained without doping, and the service life and stability of the perovskite solar cell are greatly improved, which is expected to help the perovskite solar cell to realize industrialization. BRIEF DESCRIPTION OF DRAWINGS

[0097] Figure 1 The nuclear magnetic hydrogen spectrum of intermediate 1;

[0098] Figure 2 The nuclear magnetic hydrogen spectrum of compound A2;

[0099] Figure 3 The nuclear magnetic hydrogen spectrum of intermediate 2;

[0100] Figure 4 The nuclear magnetic hydrogen spectrum of compound A2;

[0101] Figure 5 The nuclear magnetic hydrogen spectrum of intermediate 3;

[0102] Figure 6 The nuclear magnetic hydrogen spectrum of intermediate 4;

[0103] Figure 7 The nuclear magnetic hydrogen spectrum of intermediate 5;

[0104] Figure 8 The nuclear magnetic hydrogen spectrum of compound A11;

[0105] Figure 9 The nuclear magnetic hydrogen spectrum of intermediate 6;

[0106] Figure 10 The nuclear magnetic hydrogen spectrum of intermediate 7;

[0107] Figure 11 The nuclear magnetic hydrogen spectrum of compound A12;

[0108] Figure 12 The IV curve of the solar cell prepared by using compound A1 as a hole transport material;

[0109] Figure 13 The IV curve of the solar cell prepared by using compound A2 as a hole transport material;

[0110] Figure 14IV curve of a solar cell prepared for compound A11 as hole transport material;

[0111] Figure 15 IV curve of a solar cell prepared for compound A12 as hole transport material;

[0112] Figure 16 Schematic diagram of perovskite solar cell structure;

[0113] Figure 17 Adsorption model and density of states of compound of comparative example 1;

[0114] Figure 18 Adsorption model and density of states of compound of comparative example 2;

[0115] Figure 19 Adsorption model and density of states of compound A1;

[0116] Figure 20 Adsorption model and density of states of compound A2;

[0117] Figure 21 Adsorption model and density of states of compound A3;

[0118] Figure 22 Adsorption model and density of states of compound A4;

[0119] Figure 23 Adsorption model and density of states of compound A5;

[0120] Figure 24 Adsorption model and density of states of compound A6;

[0121] Figure 25 Adsorption model and density of states of compound A7;

[0122] Figure 26 Adsorption model and density of states of compound A8;

[0123] Figure 27 Adsorption model and density of states of compound A9;

[0124] Figure 28 Adsorption model and density of states of compound A10;

[0125] Figure 29 Adsorption model and density of states of compound A11;

[0126] Figure 30 Adsorption model and density of states of compound A12. DETAILED DESCRIPTION

[0127] The technical solutions of the present application are further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments are only used to help understand the present application and should not be regarded as specific limitations on the present application.

[0128] Example 1

[0129] Synthesis of compound A1

[0130]

[0131] Step 1: Synthesis of intermediate 1

[0132] Under nitrogen atmosphere, starting material 1 (1.08 g, 3.0 mmol) and starting material 2 (0.82 g, 3.0 mmol) were dissolved in 25 mL of N,N’-dimethylacetamide, followed by the addition of K2CO3(0.83 g, 6.0 mmol) and cuprous iodide (1.14 g, 6.0 mmol). The reaction mixture was reacted at 180 o C for 24 h. After the reaction was completed, it was cooled to room temperature. Diluted with water, then extracted with dichloromethane. The organic layer was dried over anhydrous magnesium sulfate, filtered and rotary evaporated. The crude product was separated by silica gel column chromatography to obtain a white solid (0.68 g, 67%).

[0133] The nuclear magnetic hydrogen spectrum of intermediate 1 is as shown in Figure 1 1 H NMR (400 MHz, DMSO-d6) δ 8.77-8.45 (m,1H), 7.83 (d, J = 0.7 Hz, 1H), 7.67-7.32 (m, 12H), 4.17 (t, J = 5.1 Hz, 2H),3.99 (dq, J = 8.5, 7.3 Hz, 4H), 1.92 (dtd, J = 11.9, 8.7, 0.6 Hz, 2H), 1.84-1.73 (m, 2H), 1.68-1.57 (m, 2H), 1.57 (s, 6H), 1.30 (td, J = 7.3, 0.7 Hz,6H).

[0134] Step 2: Synthesis of compound A1

[0135] ​In a 50 mL oven dried round bottom flask, intermediate 1 (0.56 g, 1 mmol) was dissolved in 20 mL dichloromethane. Trimethylsilyl bromide (0.612 g, 0.528 mL, 4 mmol) was added drop wise to the well stirred mixture at room temperature. After 12 h, the mixture was carefully transferred to a 100 mL round bottom flask and concentrated under reduced pressure. A magnetic stir bar and 20 ml of methanol were then added sequentially. The mixture was stirred at room temperature for 4 h, the mixture was filtered, rinsed with methanol (3 x 5 mL), and the combined filtrates were concentrated under reduced pressure to give a solid as a crude product. Recrystallization with methanol / dichloromethane / ether gave a white solid (0.3 g, 62%).

[0136] The nuclear magnetic hydrogen spectrum of compound A1 is shown in Figure 2 1 H NMR (400 MHz, DMSO-d6) δ 8.69-8.64 (m, 1H), 8.34 (s, 2H), 7.83 (d, J = 0.7 Hz, 1H), 7.67-7.32 (m, 12H), 4.17 (t, J = 5.1 Hz, 2H), 1.93-1.74 (m, 4H), 1.73-1.60 (m, 2H), 1.57 (s, 6H).

[0137] Example 2

[0138] Synthesis of compound A2

[0139]

[0140] Step 1: Synthesis of intermediate 2

[0141] Under nitrogen atmosphere, starting material 3 (1.58 g, 3.0 mmol) and starting material 2 (0.82 g, 3.0 mmol) were dissolved in 25 mL N,N’-dimethylacetamide followed by addition of K2CO3 (0.83 g, 6.0 mmol) and cuprous iodide (1.14 g, 6.0 mmol). The reaction mixture was reacted at 180 °C for 24 h. After completion of the reaction, it was cooled to room temperature. Diluted with water and extracted with dichloromethane. The organic layer was dried over anhydrous magnesium sulfate, filtered and concentrated. The crude product was purified by silica gel column chromatography to get a white solid (0.96 g, 64%).

[0142] The nuclear magnetic hydrogen spectrum of intermediate 2 is shown in Figure 3 1 ​​H NMR (400 MHz, DMSO-d6) δ 8.69 (d, J =2.4 Hz, 1H), 8.16-8.07 (m, 2H), 7.83 (d, J = 0.7 Hz, 1H), 7.69-7.63 (m, 2H),7.63-7.47 (m, 6H), 7.47-7.28 (m, 9H), 4.17 (t, J = 5.1 Hz, 2H), 3.99 (dq, J =8.6, 7.3 Hz, 4H), 1.92 (dtd, J = 11.9, 8.7, 0.6 Hz, 2H), 1.84-1.73 (m, 2H),1.68-1.56 (m, 8H), 1.30 (td, J = 7.3, 0.7 Hz, 6H)。

[0143] Step 2: Synthesis of compound A2

[0144] In a 50 mL oven dried round bottom flask, intermediate 2 (0.72 g, 1 mmol) was dissolved in 20 mL dichloromethane. Trimethylsilyl bromide (0.612 g, 0.528 mL, 4 mmol) was added dropwise to the well stirred mixture at room temperature. After 12 hours, the mixture was carefully transferred to a 100 mL round bottom flask and concentrated under reduced pressure. A magnetic stir bar and 20 ml of methanol were added in sequence. The mixture was stirred at room temperature for 4 hours, the mixture was filtered, rinsed with methanol (3 x 5 mL), and the combined filtrates were concentrated under reduced pressure to give a solid as a crude product. Recrystallization with methanol / dichloromethane / ether gave a white solid (0.38 g, 60%).

[0145] The nuclear magnetic hydrogen spectrum of compound A2 is as shown in Figure 4 , 1 H NMR (400 MHz, DMSO-d6) δ 8.69 (dd, J =2.3, 0.7 Hz, 1H), 8.34 (s, 2H), 8.16–8.07 (m, 2H), 7.83 (d, J = 0.7 Hz, 1H),7.69–7.63 (m, 2H), 7.63–7.47 (m, 6H), 7.47–7.44 (m, 1H), 7.44–7.28 (m, 8H),4.17 (t, J = 5.1 Hz, 2H), 1.93-1.74 (m, 4H), 1.73–1.60 (m, 2H), 1.57 (s, 6H)。

[0146] The preparation of compounds A3-A10 was carried out in a similar manner and is not described here again.

[0147] Example 3

[0148] Synthesis of compound A11

[0149]

[0150] Step 1 : Synthesis of intermediate 3

[0151] The starting material 1 (1 g, 2.79 mmol), starting material 4 (3.95 g, 16.76 mmol) and potassium phosphate (1.32 g, 6.18 mmol) were dissolved in dry NMP (12 mL) and the reaction was carried out under argon atmosphere. The reaction mixture was stirred at 160 °C for 40 h. After completion of the reaction, the mixture was added to saturated brine (100 mL) and extracted with dichloromethane (3 x 100 mL). The combined extracts were concentrated under reduced pressure and the product was isolated by column chromatography (silica gel: 200-300 mesh; n-hexane: dichloromethane 4:1 (v / v) as eluent) to obtain a white solid (1.09 g, 76%). o

[0152] The nuclear magnetic hydrogen spectrum of intermediate 3 is shown in Figure 5 , 1 H NMR (400 MHz, DMSO-d6) δ 8.48 (d, J =2.3 Hz, 1H), 7.83 (d, J = 0.9 Hz, 1H), 7.78-7.72 (m, 1H), 7.69-7.32 (m, 15H),1.57 (s, 6H).

[0153] Step 2: Synthesis of intermediate 4

[0154] To a solution of intermediate 3 (1 g, 1.94 mmol) in triethylamine (10 mL) were added diethyl vinylphosphonate (0.96 g, 5.82 mmol), tris(o-tolyl)phosphine (0.16 g, 0.52 mmol) and palladium(II) acetate (0.020 g, 0.089 mmol) successively at room temperature under nitrogen protection, and the reaction mixture was stirred at 100 °C under nitrogen protection for 12 h; the reaction solution was cooled to below 15 °C, 1 mol / L HCl solution (100 mL) was added, then diethyl ether (100 mL) was added, and stirred for 10 min; the liquid was separated, the aqueous phase was extracted with diethyl ether (50 mL), the organic layers were combined, dried over anhydrous Na2SO4 and filtered. The crude product was separated by silica gel column chromatography to obtain intermediate 4 (0.823 g, 71%). ​

[0155] The nuclear magnetic hydrogen spectrum of intermediate 4 is shown in Figure 6 1 H NMR (400 MHz, DMSO-d6) δ 8.48 (d, J =2.3 Hz, 1H), 7.83 (d, J = 1.0 Hz, 1H), 7.78-7.72 (m, 1H), 7.69-7.29 (m, 13H),7.28-7.20 (m, 2H), 3.97 (dq, J = 8.5, 7.2 Hz, 4H), 2.83 (d, J = 10.0 Hz, 2H),2.27 (dt, J = 12.0, 9.1 Hz, 2H), 1.57 (s, 6H), 1.30 (td, J = 7.3, 0.7 Hz,6H).

[0156] Step 3: Synthesis of intermediate 5

[0157] Under nitrogen protection, sodium borohydride (1.0 g, 24.1 mmol) was slowly added to a solution of intermediate 4 (0.7 g, 1.17 mmol) and cobalt chloride (0.36 g, 2.8 mmol) in methanol in a 100 mL single-necked round-bottom flask, stirred for 1 hour; the mixture was diluted with diethyl ether (100 ml), washed with H2O and saturated NH4Cl, then dried with anhydrous Na2SO4 and filtered; the solvent was removed under vacuum to obtain the crude product; the crude product was separated by column chromatography with hexane / ethyl acetate as eluent (15: 1, v:v) to obtain intermediate 5 (0.568 g, 81%) as a colorless oily liquid.

[0158] The nuclear magnetic hydrogen spectrum of intermediate 5 is shown in Figure 7 1 H NMR (400 MHz, DMSO-d6) δ 8.48 (d, J =2.3 Hz, 1H), 7.83 (d, J = 1.0 Hz, 1H), 7.78-7.72 (m, 1H), 7.69-7.29 (m, 13H),7.28-7.20 (m, 2H), 3.97 (dq, J = 8.5, 7.2 Hz, 4H), 2.83 (d, J = 10.0 Hz, 2H),2.27 (dt, J = 12.0, 9.1 Hz, 2H), 1.57 (s, 6H), 1.30 (td, J = 7.3, 0.7 Hz,6H).

[0159] Step 4: Synthesis of compound A11

[0160] ​​In a 50 mL oven dried round bottom flask, intermediate 5 (0.5 g, 0.834 mmol) was dissolved in 20 mL of 1,4-dioxane and trimethylsilyl bromide (0.612 g, 4 mmol) was added drop wise at room temperature; after 12 hours, the mixture was transferred to a 100 mL round bottom flask and concentrated under reduced pressure; then a magnetic stir bar and 20 mL of methanol were added successively and stirred at room temperature for 4 hours, filtered, rinsed with methanol (3 x 5 mL) and the combined filtrates were concentrated under reduced pressure to obtain the crude product; recrystallization with methanol / dichloromethane / ether afforded compound A11 as a white solid (0.29 g, 64%).

[0161] The H NMR of compound A11 is shown in Figure 8 1 H NMR (400 MHz, DMSO-d6) δ 9.13 (s, 2H), 8.48 (d, J = 2.3 Hz, 1H), 7.83 (s, 1H), 7.78-7.72 (m, 1H), 7.69-7.29 (m, 13H), 7.24 (dt, J = 7.8, 0.9 Hz, 2H), 2.84 (d, J = 8.8 Hz, 2H), 2.18 (dt, J = 11.9, 9.9 Hz, 2H), 1.57 (s, 6H).

[0162] MS m / z: [M-H] - C 35 H 29 NO3P - Calculated 542.62, found 542.71.

[0163] Example 4

[0164] Synthesis of compound A12

[0165]

[0166] Step 1: Synthesis of intermediate 6

[0167] ​Intermediate 1 (1 g, 2.79 mmol) and starting material 5 (3.19 g, 11.16 mmol) were dissolved in 25 mL of N,N-dimethylacetamide (DMAc) followed by the addition of potassium carbonate (1.60 g, 11.60 mmol) and cuprous iodide (0.40 g, 2.12 mmol). The mixture was stirred at 180 °C for 24 hours. After cooling to room temperature, the resulting mixture was washed with water and extracted with dichloromethane. The organic layers were combined and dried over anhydrous magnesium sulfate. After evaporation of the solvent under reduced pressure, the crude product was purified by column chromatography on silica gel (petroleum ether / dichloromethane = 4: 1 as eluent) to give colorless crystals (1.10 g, 70%).

[0168] The nuclear magnetic hydrogen spectrum of intermediate 6 is shown in Figure 9 1 H NMR (400 MHz, DMSO-d6) δ 8.51-8.46 (m, 1H), 8.01 (td, J = 2.1, 0.6 Hz, 1H), 7.98-7.91 (m, 1H), 7.90-7.73 (m, 5H), 7.71-7.32 (m, 12H), 1.57 (s, 6H).

[0169] Step 2: Synthesis of intermediate 7

[0170] Intermediate 7 (0.62 g, 1 mmol), diethyl phosphite (0.3 mL, 2.13 mmol), Pd(OAc)2(0.016 g, 0.071 mmol), 1,1’-bis(diphenylphosphino)ferrocene (0.08 g, 0.144 mmol) and potassium acetate (0.42 g, 4.26 mmol) were dissolved in 25 mL of dry toluene and the reaction was carried out under nitrogen protection. The mixture was heated to 110 °C for 24 hours. After cooling to room temperature, the solvent was removed under reduced pressure. The resulting mixture was washed with saturated brine and extracted with ethyl acetate. The organic layer was dried over anhydrous magnesium sulfate and the solvent was removed under reduced pressure. The crude product was purified by column chromatography on silica gel (eluent: CH2Cl2:CH3OH = 50: 1) to give a colorless solid (0.49 g, 79%).

[0171] The nuclear magnetic hydrogen spectrum of intermediate 7 is shown in Figure 10 1 ​​H NMR (400 MHz, DMSO-d6) δ 8.51-8.46 (m, 1H), 8.25-8.20 (m, 1H), 8.11-8.00 (m, 2H), 7.95-7.89 (m, 1H), 7.83 (d, J =0.7 Hz, 1H), 7.79-7.32 (m, 14H), 4.13 (dq, J = 8.5, 6.9 Hz, 4H), 1.57 (s,6H), 1.31 (td, J = 6.9, 0.7 Hz, 6H).

[0172] Step 3: Synthesis of compound A12

[0173] Intermediate 7 (0.4 g, 0.64 mmol) was dissolved in 30 mL of dichloromethane. Trimethylsilyl bromide (0.6 mL, 5.30 mmol) was added dropwise slowly. The mixture was stirred at room temperature for 12 hours. After the reaction was completed, the reaction was quenched with 10 mL of methanol and then 20 mL of dichloromethane was added and stirred for 1 hour. The solvent was removed under reduced pressure. After filtration, the solid was washed with deionized water and diethyl ether to obtain a white solid (0.267 g, 74%).

[0174] The nuclear magnetic hydrogen spectrum of compound A12 is shown in Figure 11 , 1 H NMR (400 MHz, DMSO-d6) δ 9.01 (s,2H), 8.51-8.46 (m, 1H), 8.39-8.33 (m, 1H), 8.06 (dd, J = 6.7, 2.2 Hz, 1H),7.96-7.89 (m, 2H), 7.79-7.72 (m, 2H), 7.72-7.66 (m, 1H), 7.66-7.61 (m, 2H),7.61-7.32 (m, 10H), 1.57 (s, 6H).

[0175] MS m / z: [M-H] - C 37 H 27 NO3P - Calculated 564.61, found 564.52.

[0176] Comparative Example 1

[0177] .

[0178] Comparative Example 2

[0179] .

[0180] Energy levels of self-assembled monolayer hole transport material

[0181] The highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) energy levels of the SAM molecules were determined by density functional theory (DFT) calculations and aligned with respect to the vacuum level. The HOMO energy level ranges from -6.0 to -5.0 eV, which is aligned with the valence band maximum of typical perovskites (e.g., the valence band maximum energy level of FAPbI3 is about -6.0 to -5.4 eV), thus achieving good hole transport. The LUMO energy level is between -2.5 and -1.0 eV, which provides a sufficient energy barrier for electron injection (e.g., the conduction band minimum energy level of FAPbI3 is about -4.1 to -3.4 eV), thus reducing charge recombination at the interface. The specific values are shown in Table 1 below.

[0182] Table 1 HOMO and LUMO energy levels of self-assembled monolayer hole transport material

[0183]

[0184] As can be seen from the data in Table 1, the compound of the present application has a suitable HOMO energy level, which matches the valence band maximum of perovskite, thus achieving good hole transport; and the LUMO energy level is greater than the conduction band minimum of perovskite, preventing electron injection of perovskite, so that the photoelectric conversion efficiency of the perovskite photovoltaic device containing the compound of the present application is improved.

[0185] Application Example 1

[0186] The self-assembled monolayer material A1 prepared in Example 1 was used to prepare a perovskite solar cell, as shown in the structure: Glass / FTO / NiOx / SAM / PVSK / C60 / SnO2 / Ag. Figure 16

[0187] The specific device preparation process is as follows:

[0188] ​First, the FTO conductive glass substrate was pretreated. The FTO glass was ultrasonically cleaned sequentially in detergent, deionized water, ethanol, and acetone for 15 minutes each, and then dried in a 75°C oven. Before use, the glass was treated with UV ozone for 10 minutes, and then a NiOx layer was prepared in air via spin coating. A 5 mg / mL NiOx aqueous solution was filtered through a 0.22 μm PTFE membrane and dropped onto the FTO substrate surface. The substrate was spin-coated at 5000 rpm for 30 s, followed by thermal annealing at 120°C for 15 minutes. The substrate with NiOx prepared was transferred to a nitrogen glove box for further preparation of self-assembled monolayers (SAMs). 110 μL of a 0.35 mg / mL Al ethanol solution was dropped onto the center of the substrate, spin-coated at 5000 rpm for 30 s, and then thermally annealed at 100°C for 10 minutes. The perovskite layer was deposited using a two-step spin-coating method, applying 110 μL of perovskite precursor solution (FA). 0.9 MA 0.05 Cs. 0.05 A 1.5M PbI3 (DMF:DMSO = 4:1) solution was dropped onto the center of the substrate. The first spin coating was performed at 2000 rpm for 20 seconds, followed by a second spin coating at 4500 rpm for 35 seconds. Ten seconds before the end of the second spin coating step, 110 μL of anisole was added uniformly to the center of the substrate, followed by thermal annealing at 110°C for 20 minutes. After the perovskite film annealing was complete and the temperature cooled to room temperature, a passivation layer was prepared. 110 μL of PDADI2 (1,3-diaminopropane dihydroiodide dissolved in isopropanol (IPA), concentration 0.5 mg / mL) solution was dropped onto the center of the substrate, and the mixture was spin-coated at 5000 rpm for 30 seconds, followed by thermal annealing at 100°C for 5 minutes. After annealing, the battery is transferred to a vapor deposition system, where a 21 nm thick C60 layer is deposited on the perovskite layer using vacuum thermal evaporation. Subsequently, a 25 nm thick SnO2 layer is deposited at 90°C using atomic layer deposition (ALD). Finally, after scraping off excess film at the common end, a 100 nm thick Ag electrode is deposited by vacuum evaporation under masked conditions.

[0189] Based on the A1 obtained in Example 1, perovskite solar cell devices were fabricated and characterized according to the above procedure. The current-voltage (J-V) characteristic curves of the cell device performance are shown below. Figure 12 The open-circuit voltage Voc is 1.164V, and the short-circuit current density Jsc is 25.50mA / cm². 2 The fill factor FF is 0.856 and the photoelectric conversion efficiency is 25.41%.

[0190] Application Example 2

[0191] The self-assembled monolayer material A2 prepared in Example 2 was used to prepare perovskite solar cells with the cell structure as shown in Figure 16 Figure 1, which is Glass / FTO / NiOx / SAM / PVSK / C60 / SnO2 / Ag. The specific device preparation procedure is as follows: First, the FTO conductive glass substrate was pretreated. The FTO glass was sequentially ultrasonically cleaned in detergent, deionized water, ethanol and acetone for 15 minutes each, and then dried in a 75°C oven. The glass was treated with ultraviolet ozone for 10 minutes before use, and then a NiOx layer was prepared by spin coating in air. A 5 mg / mL aqueous solution of NiOx was filtered through a 0.22 pm PTFE filter membrane and then added dropwise to the surface of the FTO substrate, which was rotated at 5000 rpm for 30 s on a spin coater, and then heat annealed at 120°C for 15 minutes. After the NiOx layer was prepared, the substrate was transferred to a nitrogen glove box for the preparation of the self-assembled monolayer (SAM). 110 pL of a 0.35 mg / mL ethanol solution of A2 was added to the center of the substrate, which was spin coated at 5000 rpm for 30 s and heat annealed at 100°C for 10 minutes. The perovskite layer was deposited by two-step spin coating, 110 pL of perovskite precursor solution (FA 0.9 MA 0.05 Cs. 0.05 PbI31.5M, DMF:DMSO volume ratio = 4:1) was added to the center of the substrate, which was rotated at 2000 rpm for 20 s in the first step and at 4500 rpm for 35 s in the second step. At 10 s before the end of the second spin coating, 110 pL of anisole was added dropwise to the center of the substrate, which was then heat annealed at 110°C for 20 minutes. After waiting for the perovskite film to anneal and cool to room temperature, the passivation layer was prepared. 110 pL of a PDADI2 solution (0.5 mg / mL dissolved in IPA) was added dropwise to the center of the substrate, which was rotated at 5000 rpm for 30 s on a spin coater and annealed at 100°C for 5 minutes on a constant temperature hot plate. After waiting for the annealing to complete, the cell was transferred to an evaporation system, 21 nm of C60 was deposited on the perovskite layer by vacuum thermal evaporation; then, 25 nm of SnO2 was deposited by atomic layer deposition (ALD) at 90°C. Finally, after removing the excess film layer from the common terminal, a 100 nm thick Ag electrode was deposited by vacuum evaporation under a mask.

[0192] Perovskite solar cell devices were prepared and characterized according to the above procedure based on A2 prepared in Example 2. The current-voltage (J-V) characteristic curve of the cell device performance is shown in Figure 13 , where the open-circuit voltage Voc is 1.158 V, the short-circuit current density Jsc is 25.29 mA / cm 2 , the fill factor FF is 0.87, and the photoelectric conversion efficiency is 25.48%.

[0193] Example 3

[0194] Example 3 was used to prepare perovskite solar cells, the cell structure is shown in Figure 16 Figure 1, which is Glass / FTO / NiOx / SAM / PVSK / C60 / SnO2 / Ag. The detailed device fabrication procedure is as follows: Firstly, the FTO conductive glass substrate was pretreated. The FTO glass was sequentially ultrasonically cleaned in detergent, deionized water, ethanol and acetone for 15 minutes, and then dried in a 75 °C oven. The glass was treated with UV-ozone for 10 minutes before use, and then a NiOx layer was prepared by spin coating in air. 5 mg / mL of NiOx aqueous solution was filtered through a 0.22 pm PTFE filter membrane and then added dropwise to the surface of the FTO substrate, which was rotated on a spin coater at 5000 rpm for 30 s, and then annealed at 120 °C for 15 minutes. After the preparation of NiOx on the substrate, the substrate was transferred to a nitrogen glove box for the preparation of self-assembled monolayers (SAMs). 110 pL of A11 ethanol solution with a concentration of 0.35 mg / mL was added to the center of the substrate, which was spin-coated at 5000 rpm for 30 s and annealed at 100 °C for 10 minutes. The perovskite layer was deposited by two-step spin coating, 110 pL of perovskite precursor solution (FA 0.9 MA 0.05 Cs. 0.05 PbI31.5M, DMF:DMSO volume ratio = 4:1) was added to the center of the substrate, the first step was rotated at 2000 rpm for 20 s and the second step was rotated at 4500 rpm for 35 s. At 10 s before the end of the second spin coating, 110 pL of anisole was added to the center of the substrate at a constant speed, and then annealed at 110 °C for 20 minutes. After waiting for the perovskite film to anneal and cool to room temperature, a passivation layer was prepared. 110 pL of PDADI2 (dissolved in IPA, 0.5 mg / mL) solution was added to the center of the substrate, which was rotated on a spin coater at 5000 rpm for 30 s and annealed on a constant temperature hot stage at 100 °C for 5 minutes. After waiting for the annealing to complete, the cell was transferred to an evaporation system, and 21 nm of C60 was deposited on the perovskite layer by vacuum thermal evaporation; then, 25 nm of SnO2 was deposited by atomic layer deposition (ALD) at 90 °C. Finally, after removing the excess film layer on the common terminal, a 100 nm thick Ag electrode was deposited by vacuum evaporation under a mask.

[0195] Perovskite solar cell devices were prepared and characterized according to the procedures described above based on A11 prepared in Example 3. The current-voltage (J-V) characteristic curve of the cell device performance is shown in Figure 14The open-circuit voltage Voc is 1.188V, and the short-circuit current density Jsc is 25.14mA / cm². 2 The fill factor FF is 0.86 and the photoelectric conversion efficiency is 25.69%.

[0196] Application Example 4

[0197] The self-assembled monolayer material Al2 obtained in Example 4 was used to prepare perovskite solar cells, and the cell structure is as follows. Figure 16 As shown, its structure is: Glass / FTO / NiOx / SAM / PVSK / C60 / SnO2 / Ag. The specific device fabrication process is as follows: First, the FTO conductive glass substrate is pretreated. The FTO glass is ultrasonically cleaned in detergent, deionized water, ethanol, and acetone for 15 minutes each, and then dried in a 75°C oven. Before use, the glass is treated with ultraviolet ozone for 10 minutes, and then a NiOx layer is prepared in air by spin coating. A 5 mg / mL NiOx aqueous solution is filtered through a 0.22 μm PTFE membrane and dropped onto the surface of the FTO substrate. It is then rotated at 5000 rpm for 30 s on a spin coater, followed by thermal annealing at 120°C for 15 minutes. The substrate after NiOx preparation is transferred to a nitrogen glove box to continue the preparation of self-assembled monolayers (SAM). 110 μL of a 0.35 mg / mL A12 ethanol solution was dropped onto the center of the substrate, and the mixture was spin-coated at 5000 rpm for 30 s, followed by thermal annealing at 100°C for 10 min. The perovskite layer was deposited using a two-step spin-coating method, with 110 μL of the perovskite precursor solution (FA) added. 0.9 MA 0.05 Cs. 0.05 A 1.5M PbI3 (DMF:DMSO volume ratio = 4:1) solution was dropped onto the center of the substrate. The first spin coating was performed at 2000 rpm for 20 seconds, followed by a second spin coating at 4500 rpm for 35 seconds. Ten seconds before the end of the second spin coating, 110 μL of anisole was added uniformly to the center of the substrate, followed by thermal annealing at 110°C for 20 minutes. After the perovskite film annealing was complete and the temperature cooled to room temperature, a passivation layer was prepared. 110 μL of PDADI2 (dissolved in IPA, 0.5 mg / mL) solution was dropped onto the center of the substrate, and the layer was spin-coated at 5000 rpm for 30 seconds, followed by annealing at 100°C for 5 minutes. After annealing, the cell was transferred to an evaporation system, where a 21 nm layer of C60 was deposited on the perovskite layer using vacuum thermal evaporation. Subsequently, a 25 nm layer of SnO2 was deposited at 90°C using atomic layer deposition (ALD). Finally, after scraping off the excess film layer at the common end, an Ag electrode with a thickness of 100 nm was deposited by vacuum evaporation under masked conditions.

[0198] Perovskite solar cell devices were prepared and characterized according to the procedure described above based on A12 prepared in Example 4. The current-voltage (J-V) characteristic curve of the cell device performance thereof is shown in Figure 15 with an open-circuit voltage Voc of 1.19 V, a short-circuit current density Jsc of 25.48 mA / cm 2 , a fill factor FF of 0.844, and a photoelectric conversion efficiency of 25.59%.

[0199] Comparative Example 1

[0200] The difference from Comparative Example 1 is only that the compound of Comparative Example 2 is used instead of compound A1 in Comparative Example 1 to prepare the perovskite solar cell.

[0201] The open-circuit voltage Voc of the cell prepared thereof is 0.887 V, the short-circuit current density Jsc is 20.12 mA / cm 2 , the fill factor FF is 0.686, and the photoelectric conversion efficiency is 12.24%.

[0202] The present application more accurately describes the transfer behavior of carriers (electrons and holes) at the heterojunction interface of SAM molecules and perovskite by heterojunction transport model calculation. When the highest occupied molecular orbital (HOMO) energy level of the SAM molecule is higher than the valence band maximum (VBM) of the perovskite, the electrons of the SAM molecule will transfer to the perovskite valence band with lower energy, and equivalently, the holes of the perovskite will transfer to the SAM, thereby realizing hole transport.

[0203] The density of states (DOS) of the complex structure formed by each SAM molecule adsorbed on the perovskite interface was simulated and calculated using first-principles DFT to elucidate the electronic structure and interface interaction. The calculation was performed using the Vienna Ab initio Simulation Package (VASP) version 6.4.2, using a hybrid functional method to balance the calculation efficiency and the accuracy of describing the band gap and localized states. The simulation workflow is as follows:

[0204] Model construction: A perovskite surface model FAPbI3 unit cell (3X3X1) was constructed, with its {001} crystal face capped with PbI2, and the SAM molecule was adsorbed through its functional group. DFT-D3 correction was used to introduce van der Waals interactions to explain non-covalent bonding. Periodic boundary conditions were applied, and a vacuum layer of at least 20 Å was set perpendicular to the interface to alleviate pseudo-interactions.

[0205] Geometry optimization: Initial structure relaxation was performed using the generalized gradient approximation (GGA) and the Perdew-Burke-Ernzerhof (PBE) functional. A plane-wave basis set with an energy cutoff of 400 eV was employed, and a 3 x 3 x 1 gamma-centered k-point mesh was used to sample the Brillouin zone. Core electrons were treated using projected augmented wave (PAW) pseudopotentials, with valence configurations including Pb's 5d 10 6s 2 6p 2 , I's 5s 2 5p 5 , and the corresponding settings for organic elements. The electronic self-consistency convergence criterion was set to 10 -5 eV, and the ionic force convergence criterion was set to 0.02 eV / A.

[0206] Electronic structure calculation: After optimization, single-point energy calculations were performed using the hybrid Heyd-Scuseria-Ernzerhof (HSE06) functional, which includes 25% exact Hartree-Fock exchange with a screening parameter of 0.2 A -1 . This hybrid approach corrects the inherent band gap underestimation of pure GGA functionals, providing a more reliable DO spectrum.

[0207] Density of states calculation: Total and projected density of states (PDOS) were calculated using a tetrahedron method with Bloch's correction to eliminate dispersion effects, ensuring high-resolution description of states near the Fermi level. The DOS was calculated in the range of -10 eV to +5 eV relative to the Fermi level with a grid spacing of 0.01 eV. The contributions of SAM molecules, perovskite lattice, and interface atoms to the PDOS were analyzed to identify hybridization effects, such as orbital overlap between the SAM π-conjugated system and perovskite valence band states.

[0208] This computational scheme reveals key interface electronic properties, including mid-gap states resulting from SAM-perovskite interactions and shifts in the effective work function, which are crucial for improving the open-circuit voltage and fill factor of solar cells.

[0209] Density of states from the SAM-perovskite composite structure Figures 17-30It can be known that the compounds A1-A12 have suitable HOMO energy levels, form energy level difference with the valence band top of perovskite, are beneficial to the transmission of holes from the perovskite to the SAM material, make the perovskite photovoltaic device containing the compound produced by the application have improved photoelectric conversion efficiency. The comparative example 2 is adsorbed on the surface of the perovskite crystal, makes the perovskite have serious lattice distortion, influences the stability of the perovskite crystal; and the HOMO energy level is equivalent to the valence band top of the perovskite, does not form energy level difference, is not beneficial to the transmission of holes from the perovskite to the SAM material.

[0210] The applicant declares that the self-assembled monolayer hole transport material of the indenocarbazole derivative of the application and the preparation method and application thereof are illustrated by the above examples, but the application is not limited to the above examples, that is, it does not mean that the application must rely on the above examples to be implemented. It should be understood by those skilled in the art that any improvement of the application, equivalent replacement of the selected raw materials of the application, addition of auxiliary ingredients, selection of specific modes, etc. fall within the protection scope and disclosure scope of the application.

Claims

1. A self-assembled monolayer hole transport material of an indobenzocarbazole derivative, characterized in that, The hole transport material has the structure shown in Formula I: ； Wherein R1 is selected from extended conjugated groups, specifically from the following groups: ； The asterisk represents the bonding site of the functional group; Where L is a linking group, selected from any one of L1 to L3: ； in This represents the connection site with the linking group.

2. The self-assembled monolayer hole transport material based on indobenzocarbazole derivatives according to claim 1, characterized in that, R1 is selected from G1, and L is selected from L1, L2, or L3.

3. The self-assembled monolayer hole transport material based on indobenzocarbazole derivatives according to claim 1, characterized in that, R1 is selected from G2, G3, G4, G5, G6, G7, G8, G9 or G10, and L is selected from L1.

4. The self-assembled monolayer hole transport material of indobenzocarbazole derivative according to claim 1, characterized in that, The self-assembled monolayer hole transport material of the indobenzocarbazole derivative is selected from any one of the following compounds A1-A12: 。 5. A method for preparing a self-assembled monolayer hole transport material of indobenzocarbazole derivatives according to any one of claims 1-4, characterized in that, The preparation method includes the following steps: (1) Synthesis of self-assembled monolayer hole transport materials with L = L1: S1-1. The reaction between compound II and compound III yields compound IV, as shown in the following reaction formula: ； The compounds S1-2 and IV undergo hydrolysis to obtain the self-assembled monolayer hole transport material based on the indencocarbazole derivative shown in Formula I, as shown in the following reaction formula: ； (2) Synthesis of self-assembled monolayer hole transport materials with L = L2: S2-1. The compound shown in formula B reacts with the compound shown in formula C to give the compound shown in formula D. The reaction formula is as follows: ； S2-2. The compound shown in formula D reacts with the compound shown in formula E to give the compound shown in formula F. The reaction formula is as follows: ； S2-3. The compound shown in formula E undergoes a hydrogenation reduction reaction to obtain the compound shown in formula E, as shown in the following reaction formula: ； S2-4 and the compound shown in formula H undergo hydrolysis to obtain the self-assembled monolayer hole transport material based on the indencocarbazole derivative shown in formula I. The reaction formula is as follows: ； (3) Synthesis of self-assembled monolayer hole transport materials with L=L3: S3-1. The reaction between compound b and compound c yields compound d, as shown in the following reaction equation: ； S3-2. The compound shown in formula d reacts with the compound shown in formula e to give the compound shown in formula f. The reaction formula is as follows: ； S3-3. The compound shown in formula f undergoes a hydrolysis reaction to obtain the self-assembled monolayer hole transport material based on indencocarbazole derivatives shown in formula I. The reaction formula is as follows: ； R2 and R3 are independently selected from C1-C5 alkyl groups, and X is selected from halogens.

6. The preparation method according to claim 5, characterized in that, R2 and R3 are independently selected from methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl or n-pentyl, preferably ethyl; X is selected from F, Cl, Br, or I.

7. The preparation method according to claim 5, characterized in that, The molar ratio of the compound of formula II to the compound of formula III in step S1-1 is 1:1-1.5; The reaction described in step S1-1 is carried out in the presence of a catalyst, namely cuprous iodide; The reaction described in step S1-1 is carried out in the presence of an alkaline substance selected from potassium carbonate and / or sodium carbonate; The reaction described in step S1-1 is carried out in an organic solvent, wherein the organic solvent is selected from N,N'-dimethylacetamide; The reaction temperature in step S1-1 is 160~180℃, and the reaction time is 20~24 h; The hydrolysis reaction described in steps S1-2 is carried out in the presence of trimethylbromosilane; The molar ratio of the trimethylbromosilane to the compound shown in Formula IV is 2:1 to 4:1; The hydrolysis reaction described in steps S1-2 is carried out in an organic solvent, wherein the organic solvent is selected from dichloromethane and / or trichloromethane; The hydrolysis reaction described in steps S1-2 is carried out at room temperature for 12-18 hours.

8. The preparation method according to claim 5, characterized in that, The molar ratio of the compound shown in formula B to the compound shown in formula C in step S2-1 is 1:5 to 1:

7. The reaction described in step S2-1 is carried out in the presence of an alkaline substance, which is selected from potassium phosphate or sodium phosphate; The reaction described in step S2-1 is carried out in an organic solvent, wherein the organic solvent is selected from N-methylpyrrolidone; The reaction temperature in step S2-1 is 160~180℃, and the reaction time is 40~48 h; The reaction described in step S2-1 is carried out under the protection of an inert gas; The molar ratio of the compound shown in formula D to the compound shown in formula E in step S2-2 is 1:3 to 1:

4. The reaction described in step S2-2 is carried out in the presence of an alkaline substance, namely triethylamine; The reaction described in step S2-2 is carried out in the presence of a ligand selected from tris(o-tolyl)phosphine; The reaction described in step S2-2 is carried out in the presence of a catalyst, namely palladium acetate; The reaction temperature in step S2-2 is 100~120℃, and the reaction time is 12~20h; The reducing agent in the hydrogenation reduction reaction described in step S2-3 is sodium borohydride; The hydrogenation reduction reaction described in steps S2-3 is carried out in the presence of a catalyst, namely cobalt chloride. The hydrogenation reduction reaction described in steps S2-3 is carried out in an organic solvent, namely methanol; The hydrogenation reduction reaction described in steps S2-3 is carried out under nitrogen protection; The hydrogenation reduction reaction described in steps S2-3 is carried out at room temperature for 1-2 hours. The hydrolysis reaction described in steps S2-4 is carried out in the presence of trimethylbromosilane; The molar ratio of the trimethylbromosilane to the compound represented by formula H is 2:1 to 4:1; The hydrolysis reaction described in steps S2-4 is carried out in an organic solvent, wherein the organic solvent is selected from 1,4-dioxane; The hydrolysis reaction described in steps S2-4 is carried out at room temperature for 12-18 hours.

9. The preparation method according to claim 5, characterized in that, The molar ratio of the compound shown in formula b to the compound shown in formula c in step S3-1 is 1:3.5 to 1:5; The reaction described in step S3-1 is carried out in the presence of an alkaline substance, which is selected from potassium carbonate or sodium carbonate. The reaction described in step S3-1 is carried out in the presence of a catalyst selected from cuprous iodide; The reaction described in step S3-1 is carried out in an organic solvent, wherein the organic solvent is selected from N,N-dimethylacetamide; The reaction temperature in step S3-1 is 160~200℃, and the reaction time is 20~30 h; The molar ratio of the compound shown in formula d to the compound shown in formula e in step S3-2 is 1:1.5 to 1:3; The reaction described in step S3-2 is carried out in the presence of a catalyst, namely palladium acetate; The reaction described in step S3-2 is carried out in the presence of a ligand selected from 1,1'-bis(diphenylphosphine)ferrocene; The reaction described in step S3-2 is carried out in the presence of an alkaline substance, namely potassium acetate; The reaction temperature in step S3-2 is 100~120℃, and the reaction time is 20~30 hours; The reaction described in step S3-2 is carried out under nitrogen protection; The hydrolysis reaction described in step S3-3 is carried out in the presence of trimethylbromosilane; The molar ratio of the trimethylbromosilane to the compound shown in formula f is 2:1 to 4:1; The hydrolysis reaction described in steps S1-2 is carried out in an organic solvent, wherein the organic solvent is selected from dichloromethane and / or trichloromethane; The hydrolysis reaction described in steps S1-2 is carried out at room temperature for 12-18 hours.

10. A perovskite solar cell, characterized in that, The perovskite solar cell comprises a self-assembled monolayer, wherein the self-assembled monolayer comprises a self-assembled monolayer hole transport material of an indocarbazole derivative as described in any one of claims 1-3.

11. The perovskite solar cell according to claim 10, characterized in that, The perovskite solar cell includes a cathode layer, an electron transport layer, a passivation layer, a perovskite light-absorbing layer, a self-assembled monolayer, a hole transport layer, and an anode layer arranged sequentially. And / or, the self-assembled monolayer is obtained by coating a solution of the self-assembled monolayer hole transport material of the indobenzocarbazole derivative as described in any one of claims 1-4 onto the surface of the hole transport layer and then performing thermal annealing. The heat annealing temperature is 80~120℃, and the heat annealing time is 5~20 minutes.

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