Self-assembled material of carbazole-fluorene derivative and preparation method and application thereof

Abstract

The application discloses a kind of carbazole-fluorene derivatives self-assembly material and its preparation method and application.The self-assembly material of the application introduces 9,9-dimethylfluorene bridging structure on the basis of carbazole skeleton, constructs carbazole-fluorene conjugated system, and then connects carbazole unit and phosphonic acid anchoring group through flexible alkyl connecting arm, forms the single-arm or double-arm molecular structure with regular structure;Through the steric hindrance effect of fluorene 9-position methyl substituent group, intermolecular interaction is regulated, and strong π-π stacking is inhibited, so as to be conducive to forming stable, ordered self-assembly monolayer on substrate surface.The material has larger π conjugated system and adjustable molecular energy level, can effectively improve interface hole transport capacity and self-assembly layer stability.The material can be used to prepare hole transport layer or interface modification layer in photovoltaic device such as perovskite solar cell, so as to improve the photoelectric conversion efficiency of device, and be conducive to improving interface stability.

Description

Technical Field

[0001] This invention belongs to the field of organic optoelectronic materials technology, and more specifically, relates to a self-assembled material of carbazole-fluorene derivative, its preparation method and application. Background Technology

[0002] Organic-inorganic hybrid perovskite solar cells have attracted widespread attention due to their high conversion efficiency and solution processing potential. Among them, the inverted (pin) device structure shows great industrialization prospects due to its advantages such as low fabrication temperature, simple process, small hysteresis effect, and good compatibility with tandem cells. In the inverted structure, the hole transport layer, as a key functional layer beneath the perovskite, is not only responsible for the efficient extraction and transport of holes, but its properties also directly affect the perovskite crystal quality and interfacial recombination.

[0003] Currently, the hole transport materials commonly used in inverted devices, such as polymers like PTAA, while widely applied, still suffer from limitations such as poor hydrophobicity and wettability, high cost, and interfacial energy level mismatch. To overcome these challenges, self-assembled monolayers (SAMs) have been considered a highly promising solution in recent years. SAMs can form dense, ordered monolayers on metal oxide substrates through specific anchoring groups (such as phosphonic acids and carboxylic acids), offering advantages such as ultrathinness, low cost, designable energy levels, and interfacial passivation.

[0004] However, most reported SAM materials are carbazole phosphonic acid derivatives, such as the PACz series materials (e.g., 2PACz). These materials typically use a single carbazole structure as the conjugated framework, resulting in a relatively small conjugated system. Furthermore, most are single-anchored structures, leaving room for improvement in interfacial bonding stability. For example, Chinese patent application CN119569778A discloses a self-assembled monomolecule using spirofluorene as a conjugated bridge. While such materials can be used to construct self-assembled layers, further optimization is needed in terms of conjugated framework control, flexible connector design, and interfacial bonding stability. Therefore, there is an urgent need in this field to develop a new type of SAM material that possesses a large conjugated system to promote hole transport, minimize interfacial loss, and enhance anchoring ability to improve interfacial stability. Summary of the Invention

[0005] The purpose of this invention is to overcome the above-mentioned defects and deficiencies in the prior art and to provide a carbazole-fluorene derivative self-assembled material.

[0006] A second objective of this invention is to provide a method for preparing the carbazole-fluorene derivative self-assembled material.

[0007] A third objective of this invention is to provide applications of the carbazole-fluorene derivative self-assembled materials.

[0008] The above-mentioned objective of this invention is achieved through the following technical solution:

[0009] This invention provides a carbazole-fluorene derivative self-assembled material having the structure shown in formula (Ⅰ):

[0010] ;

[0011] R1 is selected from hydrogen, methyl, methoxy, methylthio, or trifluoromethyl;

[0012] The R2 is selected from the following groups: (a) 9,9-dimethylfluorene-2-yl, (b) 9,9-dimethylfluorene-3-yl, (c) 9,9-dimethylfluorene-2,7-diyl, (d) 9,9-dimethylfluorene-3,6-diyl, with specific substitution structures shown below:

[0013] , where * indicates a connection site;

[0014] R3 is selected from hydrogen or group (e), and the specific structural formula of group (e) is as follows:

[0015] , where * indicates a connection site;

[0016] Furthermore, R2 and R3 satisfy the following conditions: when R2 is (a) or (b), R3 is hydrogen, and the molecule has a "branched" single-arm structure, consisting of a 9,9-dimethylfluorene group connected to a phosphonic acid anchoring group via a carbazole unit; when R2 is (c) or (d), R3 is group (e), and the molecule has a symmetrical two-arm structure, consisting of a 9,9-dimethylfluorene group connected to two phosphonic acid anchoring groups via two carbazole units, forming a double-anchored structure; L represents the connecting arm, L = (CH2). n n = 1 to 10, preferably n is 4.

[0017] This invention designs and develops a novel class of carbazole-fluorene derivative self-assembled materials. By introducing a 9,9-dimethylfluorene bridging structure onto the carbazole backbone, a carbazole-fluorene conjugated system is constructed, thereby expanding the molecular π-conjugation system and extending the π-electron delocalization range, which is beneficial for enhancing intramolecular charge transport capabilities. Simultaneously, the introduction of a methyl group at the 9-position of fluorene utilizes steric hindrance to suppress intermolecular π-π stacking, helping to improve the molecular arrangement on the substrate surface and enhance interfacial stability. Furthermore, through structural design, single-anchored or double-anchored structures can be formed, increasing the adsorption strength of molecules on metal oxide substrates. Therefore, the carbazole-fluorene derivative self-assembled materials provided by this invention have significant advantages in molecular structure design, charge transport capabilities, and interfacial bonding capabilities, and can effectively improve the interfacial charge transport characteristics of perovskite solar cells and enhance device performance.

[0018] Furthermore, the structure of the carbazole-fluorene derivative self-assembled material is selected from any of the following:

[0019] .

[0020] This invention also provides a method for preparing the above-described carbazole-fluorene derivative self-assembled material, comprising the following steps:

[0021] (1) Alkylation reaction: Using R1-substituted 3-bromocarbazole as the starting material, N-alkylation reaction is carried out with excess dibromoalkane under phase transfer catalysis to introduce a flexible chain with bromine at the end;

[0022] ;

[0023] Wherein, R1 is selected from hydrogen, methyl, methoxy, methylthio, or trifluoromethyl; L = (CH2) n n = 1~10;

[0024] (2) Suzuki coupling reaction: Compound A is coupled with 9,9-dimethylfluorenylboronic acid ester with a specific substitution site via a palladium-catalyzed coupling reaction to construct a carbazole-fluoren core skeleton, yielding compound B or C;

[0025] ;

[0026] (3) Arbuzov reaction: The bromine group at the end of compound B or C reacts with triethyl phosphite via the Arbuzov reaction to generate diethylphosphonate, yielding compound D or E;

[0027] ;

[0028] (4) Hydrolysis reaction: Compound D or E loses its ethyl group under the action of trimethylbromosilane, and then hydrolyzes in a methanol and water system to obtain the final target product compound F or G, namely the carbazole-fluorene derivative self-assembled material.

[0029] .

[0030] Further, in step (1), the reaction temperature is 40-100 °C and the reaction time is 5-24 h; preferably, the reaction temperature is 60 °C and the reaction time is 6-12 h.

[0031] Further, in step (1), the base is potassium hydroxide and the phase transfer catalyst is tetrabutylammonium bromide.

[0032] Furthermore, in step (1), the dibromoalkane has the structure Br-(CH2). n-Br, where n = 1 to 10; preferably, the dibromoalkane is 1,4-dibromobutane;

[0033] Further, in step (1), the molar ratio of the R1-substituted 3-bromocarbazole, the base, the dibromoalkane and the catalyst is 1:(5-10):(5-10):(0.1-1); preferably 1:5:10:0.1.

[0034] Further, in step (2), the reaction temperature is 60-120 °C and the reaction time is 10-30 h; preferably, the reaction temperature is 90 °C and the reaction time is 12 h.

[0035] Furthermore, in step (2), the palladium catalyst for the reaction is 1,1'-bis(diphenylphosphine)ferrocene palladium dichloride.

[0036] Furthermore, in step (2), the alkali is potassium phosphate.

[0037] Further, in step (2), the solvent is a mixed solvent of deoxygenated 1,4-dioxane and water, and the ratio of the mixed solvent of 1,4-dioxane and water is 4:1.

[0038] Further, in step (2), when the 9,9-dimethylfluorenylboronic acid ester is a monoboronic acid ester, the molar ratio of compound A, monoboronic acid ester and palladium catalyst is 1:(1~2):(0.1~0.2); when the 9,9-dimethylfluorenylboronic acid ester is a diboronic acid ester, the molar ratio of compound A, diboronic acid ester and palladium catalyst is (2~3):1:(0.05~0.2).

[0039] Further, in step (3), the reaction temperature is 140-160 °C, and the reflux reaction is carried out for 5-24 h; preferably, the reaction temperature is 160 °C, and the reaction time is 22-24 h.

[0040] Further, in step (3), the molar ratio of compound B or C to triethyl phosphite is 1:(30-32).

[0041] Further, in step (4), the temperature of reaction 1) is 15-40 ℃ and the reaction time is 12-24 h, the temperature of reaction 2) is 10-35 ℃ and the reaction time is 3-12 h; preferably, the temperature of reaction 1) is 35 ℃ and the reaction time is 12-24 h, and the reaction time of reaction 2) is 3-12 h.

[0042] The present invention also provides the application of the carbazole-fluorene derivative self-assembled material in the preparation of functional layers in optoelectronic devices.

[0043] Furthermore, it is used to prepare hole transport layers or interface modification layers for perovskite solar cells. It is particularly suitable for pin-type perovskite solar cells, where the self-assembled material is deposited on a transparent conductive substrate, located below the perovskite light-absorbing layer, for efficient hole extraction and improvement of perovskite film quality.

[0044] Preferably, the transparent conductive substrate is at least one of ITO conductive glass or FTO conductive glass, but is not limited thereto.

[0045] Preferably, the hole transport layer or interface modification layer is prepared from the self-assembled monomolecular hole transport material described in this invention.

[0046] Preferably, the perovskite light-absorbing layer is composed of Cs. 0.05 (FA 0.92 MA 0.08 ) 0.95 Pb (I 0.92 Br 0.08 )3, with a band gap of 1.56 eV.

[0047] Preferably, a perovskite passivation layer is further contained between the perovskite light-absorbing layer and the electron transport layer; more preferably, the perovskite passivation layer is an EDADI layer.

[0048] Preferably, the material of the electron transport layer includes methyl [6,6]-phenyl C61 butyrate (PC). 61 One or both of BM) or 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP);

[0049] Preferably, the counter electrode is a metal electrode layer; more specifically, the metal electrode layer includes, but is not limited to, a silver electrode layer.

[0050] Preferably, the method for fabricating the inverted perovskite solar cell includes the following steps:

[0051] A solution containing the self-assembled material of the present invention is applied to the surface of the transparent conductive substrate to prepare the hole transport layer or interface modification layer; a perovskite precursor solution is spin-coated onto the surface of the hole transport layer, an anti-solvent is added during the spin-coating process, and then the perovskite layer is prepared by annealing; the electron transport layer and the counter electrode layer are sequentially prepared on the surface of the perovskite layer.

[0052] Preferably, the antisolvent is methyl tert-butyl ether, chlorobenzene, ethyl acetate, or diethyl ether.

[0053] Preferably, the solvent in the perovskite precursor solution is a mixture of a first solvent and a second solvent, wherein the first solvent is N,N-dimethylformamide (DMF), and the second solvent is one or more of dimethyl sulfoxide (DMSO), N-methylpyrrolidone, 2-methoxyethanol, and N,N-dimethylpropenylurea. The volume ratio of the first solvent to the second solvent is 3 to 5:1.

[0054] Preferably, the solutes in the perovskite precursor solution are lead iodide, formamidinium hydroiodate, lead bromide, methylammonium bromide, methylammonium chloride, and cesium iodide.

[0055] Preferably, the annealing temperature is 90–110 °C and the annealing time is 60–65 min.

[0056] Compared with the prior art, the present invention has the following beneficial effects:

[0057] This invention provides a self-assembled material of carbazole-fluorene derivatives. By introducing a 9,9-dimethylfluorene bridging structure, the molecular π-conjugation system is expanded, enhancing intramolecular charge delocalization and thus improving hole transport capability. Introducing a methyl group at the 9-position of fluorene suppresses excessive π-π stacking between molecules through steric hindrance, facilitating the formation of a more stable and ordered self-assembled monolayer structure. Structural design to form single-anchored or double-anchored phosphonic acid structures enhances the bonding strength between the molecule and the metal oxide substrate, improving the stability of the self-assembled layer. Introducing substituents with different electronic properties onto the carbazole unit allows for the modulation of the molecular HOMO energy level, thereby optimizing the energy level matching relationship with the perovskite light-absorbing layer. Inverted perovskite solar cells prepared using this material as the hole transport layer exhibit excellent photoelectric performance, with a photoelectric conversion efficiency exceeding 23%. Attached Figure Description

[0058] Figure 1 Compound b obtained in Example 1 1 H NMR spectrum (Bruker 400 MHz, CDCl3).

[0059] Figure 2 Compound b obtained in Example 1 13 C10 NMR spectrum (Bruker 101 MHz, CDCl3).

[0060] Figure 3 This is a high-resolution mass spectrum (ESI) of compound b obtained in Example 1.

[0061] Figure 4 Compound c obtained in Example 1 1 H NMR spectrum (Bruker 400 MHz, CDCl3).

[0062] Figure 5 Compound c obtained in Example 1 13 C10 NMR spectrum (Bruker 101 MHz, CDCl3).

[0063] Figure 6 Compound c obtained in Example 1 31 P NMR spectrum (Bruker 162 MHz, CDCl3).

[0064] Figure 7 This is the high-resolution mass spectrum (ESI) of compound c obtained in Example 1.

[0065] Figure 8 The self-assembled material SAM-1 prepared in Example 1 1 H NMR spectrum (Bruker 600 MHz, DMSO-d6).

[0066] Figure 9 The self-assembled material SAM-1 prepared in Example 1 13 C NMR spectrum (Bruker 151 MHz, DMSO-d6).

[0067] Figure 10 The self-assembled material SAM-1 prepared in Example 1 31 P NMR spectrum (Bruker 243 MHz, DMSO-d6).

[0068] Figure 11 This is a high-resolution mass spectrum (ESI) of the self-assembled material SAM-1 prepared in Example 1.

[0069] Figure 12 Compound d obtained in Example 2 1 H NMR spectrum (Bruker 400 MHz, CDCl3).

[0070] Figure 13 Compound d obtained in Example 2 13 C10 NMR spectrum (Bruker 101 MHz, CDCl3).

[0071] Figure 14 The image shows the high-resolution mass spectrum (ESI) of compound d obtained in Example 2.

[0072] Figure 15 Compound e obtained in Example 2 1 H NMR spectrum (Bruker 400 MHz, CDCl3).

[0073] Figure 16 Compound e obtained in Example 2 13 C10 NMR spectrum (Bruker 101 MHz, CDCl3).

[0074] Figure 17 Compound e obtained in Example 2 31 P NMR spectrum (Bruker 162 MHz, CDCl3).

[0075] Figure 18 This is the high-resolution mass spectrum (ESI) of compound e obtained in Example 2.

[0076] Figure 19 The self-assembly material SAM-11 prepared in Example 2 1 H NMR spectrum (Bruker 600 MHz, DMSO-d6).

[0077] Figure 20 The self-assembly material SAM-11 prepared in Example 2 13 C NMR spectrum (Bruker 151 MHz, DMSO-d6).

[0078] Figure 21 The self-assembly material SAM-11 prepared in Example 2 31 P NMR spectrum (Bruker 243 MHz, DMSO-d6).

[0079] Figure 22 This is a high-resolution mass spectrum (ESI) of the self-assembled material SAM-11 prepared in Example 2.

[0080] Figure 23 Information related to the DFT calculation of self-assembled materials SAM-1 and SAM-11.

[0081] Figure 24 This is a schematic diagram of the device structure in Example 3. Detailed Implementation

[0082] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but the embodiments do not limit the present invention in any way. Unless otherwise specified, the reagents, methods and equipment used in the present invention are conventional reagents, methods and equipment in this technical field.

[0083] Unless otherwise specified, all reagents and materials used in the following examples are commercially available.

[0084] Example 1: Synthesis of self-assembled material SAM-1

[0085]

[0086] 1. Synthesis of compound a

[0087] 3-Bromocarbazole (1.0 g, 4.1 mmol, 1.0 eq) and tetrabutylammonium bromide (131.4 mg, 0.4 mmol, 0.1 eq) were added to a two-necked flask, followed by the injection of 1,4-dibromobutane (8.7 g, 40.8 mmol, 10.0 eq), then toluene (3 mL) and 50% KOH aqueous solution (3 mL). The reaction was carried out under argon protection at 60 °C for 12 h, and monitored by TLC (DCM / PE = 1 / 3, v / v). After post-treatment and column chromatography (eluent DCM / PE = 1 / 6, v / v), compound a (1.3 g, 84% yield) was obtained.

[0088] 2. Synthesis of compound b

[0089] Under Ar atmosphere, compound a (1.0 g, 2.6 mmol, 1.0 eq), 9,9-dimethylfluorene-2-borate pinaester (1.0 g, 3.2 mmol, 1.2 eq), K3PO4 (1.7 g, 7.9 mmol, 3.0 eq), and Pd(dppf)Cl2 (193.0 mg, 0.3 mmol, 0.1 eq) were added sequentially to a two-necked flask after anhydrous and oxygen-free treatment. The mixture was evacuated and then argon was added three times. A 10 mL mixture of deoxygenated 1,4-dioxane / water (4 / 1) solvent was then injected. The mixture was pre-stirred at room temperature for 10 min, and then placed in a 90 °C oil bath for reaction. The reaction was allowed to proceed for 12 h, and TLC monitoring was performed (DCM / PE = 1 / 10, v / v). After post-treatment and column chromatography (eluent DCM / PE = 1 / 10, v / v), compound b (902.3 mg, 69% yield) was obtained. Compound b 1 H NMR spectrum as shown Figure 1 As shown, 1H NMR (400 MHz, CDCl3) δ 8.37 (s, 1H), 8.18 (d, J = 7.7 Hz, 1H), 7.81 – 7.74 (m, 4H), 7.68 (d, J = 7.8 Hz, 1H), 7.50 – 7.44 (m, 3H), 7.40 (d, J = 8.2 Hz, 1H), 7.37 –7.30 (m,2H), 7.26 (t, J = 7.4 Hz, 1H), 4.36 (t, J = 6.8 Hz, 2H), 3.37 (t, J =6.4 Hz, 2H), 2.11 – 2.04 (m, 2H), 1.95 – 1.88 (m, 2H), 1.57 (s, 6H). Compound b 13 The C NMR spectrum is as follows Figure 2 As shown, 13 C NMR (101 MHz, CDCl3) δ 154.44, 153.96, 141.41,140.88, 139.88, 139.19, 137.80, 133.08, 127.17, 127.13, 126.45, 126.07,125.56, 123.59, 123.20, 122.73, 121.67, 120.71, 120.43, 120.09, 119.26,119.10, 108.92, 108.85, 47.09, 42.42, 33.30, 30.35, 27.82, 27.45. The high-resolution mass spectrum (ESI) of compound b is shown below. Figure 3 As shown, HRMS (ESI) m / z: [M] + Calcd for C 31 H 28 BrN 493.13996; Found 493.14001.

[0090] 3. Synthesis of compound c

[0091] Compound b (1.0 g, 2.0 mmol, 1.0 eq) and triethyl phosphite (10.1 g, 60.8 mmol, 30.0 eq) were added to a two-necked flask after anhydrous and oxygen-free treatment. The mixture was evacuated and then purged with argon three times, and reacted at 160 °C for 24 h. The reaction was monitored by TLC (EA / PE = 1 / 1, v / v). After post-treatment and column chromatography (eluent DCM / MeOH = 100 / 1, v / v), compound c (952.0 mg, 85% yield) was obtained. The composition of compound c...1 H NMR spectrum as shown Figure 4 As shown, 1 ¹H NMR (400 MHz, CDCl₃) δ 8.36 (s, 1H), 8.18 (d, J = 7.7 Hz, 1H), 7.81 – 7.74 (m, 4H), 7.68 (d, J = 7.8 Hz, 1H), 7.50 – 7.24 (m, 7H), 4.35 (t, J = 7.1 Hz, 2H), 4.06 – 3.98 (m, 4H), 2.05– 1.98 (m, 2H), 1.76 – 1.67 (m, 4H), 1.58 (s, 6H), 1.24 (t, J = 7.0 Hz, 6H). Compound c... 13 The C NMR spectrum is as follows Figure 5 As shown, 13 C NMR (101 MHz, CDCl3) δ 154.42, 153.95,141.46, 140.91, 139.92, 139.18, 137.77, 133.01, 127.15, 127.11, 126.41,126.00, 125.49, 123.56, 123.18, 122.70, 121.63, 120.64, 120.40, 120.06,119.18, 119.04, 108.94, 108.87, 61.66 (d, J = 7.0 Hz), 47.07, 42.78, 29.90(d, J = 15.1 Hz), 27.43, 25.58 (d, J = 140.8 Hz), 20.58 (d, J = 5.0 Hz), 16.53 (d, J = 6.0 Hz). 31 p NMR spectrum as shown Figure 6 As shown, 31 P NMR (162 MHz, CDCl3) δ 36.22. The high-resolution mass spectrum (ESI) of compound c is shown below. Figure 7 As shown, HRMS (ESI) m / z: [M] + Calcd for C 35 H 38 NO3P551.25838; Found 551.25861.

[0092] 4. Synthesis of self-assembled material SAM-1

[0093] Compound c (200.0 mg, 0.4 mmol, 1.0 eq) was added to a flask, followed by 1,4-dioxane (5 mL) and trimethylbromosilane (1.2 g, 7.6 mmol, 20.9 eq) under argon protection. The reaction mixture was allowed to react at room temperature for 24 h, and the solution was evaporated to dryness. Then, methanol (5 mL) and deionized water (5 mL) were added, and the reaction was allowed to continue at room temperature for 12 h. The solution was then evaporated to dryness. After washing with deionized water and ethyl acetate, the mixture was dried under vacuum for 24 h to obtain the self-assembled material SAM-1 (133.1 mg, 74% yield). SAM-1... 1 H NMR spectrum as shown Figure 8 As shown, 1 H NMR (600 MHz, DMSO-d6) δ 8.57 (s, 1H), 8.29 (d, J = 7.7 Hz, 1H), 7.99 (s, 1H), 7.90 (d, J = 7.7 Hz, 1H), 7.85 (d, J = 7.4 Hz, 2H), 7.76 (d, J= 7.6 Hz, 1H), 7.70 (d, J = 8.5 Hz, 1H), 7.64 (d, J = 8.2 Hz, 1H), 7.57 (d, J= 7.3 Hz, 1H), 7.47 (t, J = 7.7 Hz, 1H), 7.37 – 7.31 (m, 2H), 7.23 (t, J =7.5 Hz, 1H), 4.44 (t, J = 7.3 Hz, 2H), 1.92 – 1.87 (m, 2H), 1.58 – 1.54 (m, 10H). SAM-1 13 The C NMR spectrum is as follows Figure 9 As shown, 13 C NMR (151 MHz, DMSO-d6) δ 154.12, 153.58,140.49, 140.47, 139.54, 138.44, 136.94, 131.46, 127.14, 127.06, 125.90,125.74, 124.91, 122.76, 122.73, 122.32, 121.10, 120.62, 120.50, 120.05,118.79, 118.47, 109.68, 109.50, 46.60, 42.19, 29.67 (d, J = 15.1 Hz), 27.46 (d, J = 141.8 Hz), 27.46 (d, J = 141.8 Hz), 20.53. SAM-1's31 p NMR spectrum as shown Figure 10 As shown, 31 P NMR (243 MHz, DMSO-d6) δ 26.08. High-resolution mass spectrum (ESI) of SAM-1 is shown below. Figure 11 As shown, HRMS(ESI) m / z: [M + Na] + Calcd for C 31 H 30 NO3PNa 518.18555; Found 518.18585.

[0094] Example 2 Synthesis of self-assembled material SAM-11

[0095]

[0096] 1. Synthesis of compound d

[0097] Compound a (1.0 g, 2.6 mmol, 2.5 eq), 9,9-dimethylfluorene-2,7-diboronic acid dipinalol ester (471.1 mg, 1.1 mmol, 1.0 eq), K3PO4 (729.4 mg, 5.3 mmol, 5.0 eq), and Pd(dppf)Cl2 (77.2 mg, 0.1 mmol, 0.1 eq) were added sequentially to a two-necked flask. The mixture was evacuated and then purged with argon three times. A deoxygenated mixture of 1,4-dioxane / water (4 / 1, 15 mL) was injected under argon protection. The reaction was carried out at 90 °C for 12 h, and monitored by TLC (DCM / PE = 1 / 5, v / v). After post-treatment and column chromatography (eluent DCM / PE = 1 / 5, v / v), compound d (262.7 mg, yield 52%) was obtained. The composition of compound d... 1 H NMR spectrum as shown Figure 12 As shown, 1 H NMR (400 MHz, CDCl3) δ 8.39 (s, 2H), 8.19 (d, J =7.7 Hz, 2H), 7.84 – 7.78 (m, 6H), 7.70 (d, J = 7.9 Hz, 2H), 7.50 – 7.39 (m,6H), 7.26 (t, J = 7.5 Hz, 2H), 4.35 (t, J = 6.9 Hz, 4H), 3.37 (t, J = 6.5 Hz, 4H), 2.11 – 2.03 (m, 4H), 1.95 – 1.88 (m, 4H), 1.66 (s, 6H). Compound d 13The C NMR spectrum is as follows Figure 13 As shown, 13 C10 NMR (101 MHz, CDCl3) δ 154.69, 141.19, 140.85, 139.85, 137.66, 133.06, 126.50, 126.04, 125.55, 123.57, 123.19, 121.62, 120.69, 120.42, 119.25, 119.04, 108.93, 108.84, 47.22, 42.35, 33.29, 30.31, 27.77, 27.62. The high-resolution mass spectrum (ESI) of compound d is shown below. Figure 14 As shown, HRMS (ESI) m / z: [M] + Calcd forC 47 H 42 Br2N2 794.16888; Found 794.16724.

[0098] 2. Synthesis of compound e

[0099] Compound d (500.0 mg, 0.6 mmol, 1.0 eq) and triethyl phosphite (3.1 g, 18.9 mmol, 30.0 eq) were added to a two-necked flask under argon protection and reacted at reflux at 160 °C for 22 h, monitored by TLC (DCM / MeOH = 40 / 1, v / v). After post-treatment and column chromatography (eluent DCM / MeOH = 40 / 1, v / v), compound e (361.2 mg, 63% yield) was obtained. The composition of compound e... 1 H NMR spectrum as shown Figure 15 As shown, 1 ¹H NMR (400 MHz, CDCl₃) δ 8.39 (s, 2H), 8.19 (d, J = 7.7 Hz, 2H), 7.86 – 7.79 (m, 6H), 7.71 (d, J = 7.8 Hz, 2H), 7.51– 7.41 (m, 6H), 7.26 (t, J = 7.4 Hz, 2H), 4.36 (t, J = 7.0 Hz, 4H), 4.07 –3.99 (m, 8H), 2.07 – 1.99 (m, 4H), 1.80 – 1.72 (m, 8H), 1.67 (s, 6H), 1.25 (t, J = 7.0 Hz, 12H). Compound e 13 The C NMR spectrum is as follows Figure 16 As shown,13 C NMR (101 MHz, CDCl3) δ154.68, 141.26, 140.91, 139.91, 137.64, 133.04, 126.48, 125.99, 125.49,123.57, 123.19, 121.63, 120.64, 120.36, 119.17, 119.02, 108.95, 108.87, 61.66(d, J = 7.0 Hz), 47.21, 42.77, 29.88 (d, J = 15.1 Hz), 27.60, 25.56 (d, J =141.8 Hz), 20.56 (d, J = 5.0 Hz), 16.52 (d, J = 6.0 Hz). Compound e 31 p NMR spectrum as shown Figure 17 As shown, 31 P NMR (162 MHz, CDCl3) δ 31.44. High-resolution mass spectrum (ESI) of compound e is shown below. Figure 18 As shown, HRMS (ESI) m / z: [M] + Calcd for C 55 H 62 N2O6P2 908.40776; Found 908.40564.

[0100] 3. Synthesis of self-assembled material SAM-11

[0101] Compound e (500.0 mg, 0.6 mmol, 1.0 eq) was added to a flask, followed by 1,4-dioxane (10 mL) and trimethylbromosilane (3.5 g, 22.7 mmol, 41.3 eq) under argon protection. The reaction mixture was allowed to react at room temperature for 24 h, and the solution was evaporated to dryness. Then, methanol (10 mL) and deionized water (10 mL) were added, and the reaction was allowed to continue at room temperature for 12 h. The solution was then evaporated to dryness. After washing with deionized water and ethyl acetate, the mixture was dried under vacuum for 24 h to obtain the self-assembled material SAM-11 (289.3 mg, 66% yield). SAM-11... 1 HNMR spectrum as follows Figure 19 As shown, 1H NMR (600 MHz, DMSO-d6) δ 8.59 (s, 2H), 8.30 (d, J = 7.7Hz, 2H), 8.01 (s, 2H), 7.94 (d, J = 7.9 Hz, 2H), 7.87 (d, J = 8.5 Hz, 2H), 7.79 (d, J = 7.9 Hz, 2H), 7.73 (d, J = 8.6 Hz, 2H), 7.65 (d, J = 8.3 Hz, 2H), 7.48 (t, J = 7.6 Hz, 2H), 7.24 (t, J = 7.4 Hz, 2H), 4.45 (t, J = 7.0 Hz, 4H),1.93 – 1.88 (m, 4H), 1.65 (s, 6H), 1.60 – 1.54 (m, 8H). SAM-11 13 The C NMR spectrum is as follows Figure 20 As shown, 13 C NMR (151 MHz, DMSO-d6) δ 154.47, 140.51, 140.26, 139.55, 136.85,131.54, 125.91, 125.80, 124.92, 122.76, 122.35, 121.10, 120.63, 120.46,118.82, 118.45, 109.69, 109.50, 46.79, 42.18, 39.10, 29.64 (d, J = 15.1 Hz), 27.36 (d, J = 135.8 Hz), 27.13, 20.48 (d, J = 4.5 Hz). SAM-11 31 p NMR spectrum as shown Figure 21 As shown, 31 P NMR (243 MHz, DMSO-d6) δ 26.48. High-resolution mass spectra (ESI) of SAM-11 are shown below. Figure 22 As shown, HRMS (ESI) m / z: [M + Na] + Calcd for C 47 H 46 N2O6P2Na 819.27233; Found 819.27277.

[0102] Example 3: Application of self-assembled materials of carbazole-fluorene derivatives in inverted perovskite solar cells

[0103] The fabrication method of the PSC device specifically includes the following steps:

[0104] Device structure: ITO glass, hole transport layer, perovskite layer, perovskite passivation layer (EDADI), electron transport layer (PC) 61 The fabrication methods for the BM layer, BCP layer, and metal electrode (Ag electrode) include the following:

[0105] (1) ITO glass

[0106] The etching process involves sequentially diluting a mixture of V-M detergent with deionized water, followed by deionized water, acetone, deionized water, and ethanol, then sonicating for 20 minutes. The resulting solution is then dried in a 60°C oven. A 5 mm wide 3M high-temperature resistant tape is applied to opposite edges of the etched area. Before spin coating, the ITO glass is treated with UVO for 30 minutes.

[0107] (2) Hole transport layer

[0108] Prepare DMF solutions (0.5 mg / mL) of SAM-1 and SAM-11, and spin-coat them statically on an ITO glass plate (80 μL, 4000 rpm, 30 s), then heat at 100 °C for 10 min.

[0109] (3) Perovskite layer Cs 0.05 (FA 0.92 MA 0.08 ) 0.95 Pb (I 0.92 Br 0.08 )3

[0110] Lead iodide (PbI2, 1.29 mmol), formamidinium hydroiodate (FAI, 1.22 mmol), lead bromide (PbBr2, 0.224 mmol), methylammonium bromide (MABr, 0.112 mmol), methylammonium chloride (MACl, 0.074 mmol), and cesium iodide (CsI, 0.0035 mmol) were dissolved in DMF:DMSO (4:1, v / v) solution to obtain a perovskite precursor solution; static spin coating (60 μL, 3000 rpm for 30 s), with chlorobenzene (200 μL) added dropwise to the center of the film in the last 10 s, and heating at 100 °C for 60 min.

[0111] (4) EDADI

[0112] EDADI (1.5 mg, ethylenediamine dihydroiodate) was dissolved in isopropanol (3 mL), stirred at 60 °C, and then spin-coated dynamically (100 μL, 5000 rpm, 30 s). The solution was then heated at 100 °C for 5 min.

[0113] (5) PC61 BM layer

[0114] PC 61 BM (40.0 mg) was dissolved in chlorobenzene (2 mL), stirred until dissolved, filtered through a 0.22 μm filter, and statically spin-coated (70 μL, 3000 rpm, 30 s), and heated at 70 °C for 10 min.

[0115] (6) BCP layer

[0116] BCP (10.0 mg) was dissolved in isopropanol (2 mL), and the mixture was statically spin-coated (70 μL, 5000 rpm, 30 s) and heated at 70 °C for 10 min.

[0117] (7) Ag layer

[0118] After removing the high-temperature resistant tape, a 100 nm thick Ag layer was deposited as an electrode using vacuum evaporation to fabricate an inverted perovskite solar cell device. A schematic diagram of the device is shown below. Figure 24 As shown.

[0119] (8) Performance testing

[0120] Using Chenhua's electrochemical workstation, with an onset voltage of 1.2 V, an end voltage of −0.1 V, and a scan rate of 0.15 V / s, at AM 1.5 G and 100 mW cm⁻¹... -2 JV tests were conducted under simulated sunlight, with the light source calibrated using a standard silicon cell. The experimental results are shown in Table 1.

[0121] Table 1 Performance parameters of the inverted perovskite solar cells prepared in Example 3

[0122]

[0123] As can be seen from Table 1, the open-circuit voltage (V) of the battery in the devices prepared by spin-coating SAM-1 and SAM-11 described in this invention is... oc ), current density (J) sc The fill factor (FF) and power conversion efficiency (PCE) are both superior to those of NiO. x It is a device for the hole transport layer.

Claims

1. A carbazole-fluorene derivative self-assembled material, characterized in that, The carbazole-fluorene derivative self-assembled material has the structure shown in formula (Ⅰ): ； R1 is selected from hydrogen, methyl, methoxy, methylthio, or trifluoromethyl; The R2 is selected from the following groups: (a) 9,9-dimethylfluorene-2-yl, (b) 9,9-dimethylfluorene-3-yl, (c) 9,9-dimethylfluorene-2,7-diyl, (d) 9,9-dimethylfluorene-3,6-diyl, with specific substitution structures as follows: * indicates a connection site; R3 is selected from hydrogen or group (e), and the specific structural formula of group (e) is as follows: * indicates a connection site; Furthermore, R2 and R3 satisfy the following conditions: when R2 is (a) or (b), R3 is hydrogen; when R2 is (c) or (d), R3 is a group (e) and its R1 group is consistent with the R1 group in formula (I); L represents the connecting arm, L = (CH2) n n = 1 to 10; preferably, n is 4.

2. The carbazole-fluorene derivative self-assembled material according to claim 1, characterized in that, The structure of the carbazole-fluorene derivative self-assembled material is selected from any of the following: 。 3. The method for preparing the carbazole-fluorene derivative self-assembled material according to claim 1 or 2, characterized in that, Includes the following steps: (1) Alkylation reaction: In the presence of an inert gas atmosphere, base and phase transfer catalyst, 3-bromocarbazole substituted with R1 is reacted with excess dibromoalkane in a solvent at 40-100 °C for 5-24 h, and compound A is obtained after post-treatment and purification; ； Wherein, R1 is selected from hydrogen, methyl, methoxy, methylthio, or trifluoromethyl; L = (CH2) n n = 1~10; (2) Suzuki coupling reaction: Compound A was reacted with the corresponding 9,9-dimethylfluorenylboronic acid ester in a solvent at 60-120 °C for 10-30 h in an inert gas atmosphere, with palladium catalyst and base. After post-treatment and purification, compound B or C was obtained. ； (3) Arbuzov reaction: Compound B or C is refluxed with triethyl phosphite at 140-160 °C for 5-24 h under an inert gas atmosphere, and then compound D or E is obtained after post-treatment and purification. ； (4) Hydrolysis reaction: Under an inert gas atmosphere, compound D or E is dissolved in an organic solvent, and trimethylbromosilane is added and reacted at 15-40 °C for 12-24 h; then the solvent is removed, and a mixture of methanol and water is added and reacted at 10-35 °C for 3-12 h. After post-treatment, the final product compound F or G is obtained, which is the carbazole-fluorene derivative self-assembled material. 。 4. The preparation method according to claim 3, characterized in that, In step (1), the molar ratio of the R1-substituted 3-bromocarbazole, base, dibromoalkane and phase transfer catalyst is 1:(5-10):(5-10):(0.1-1).

5. The preparation method according to claim 3, characterized in that, In step (2), when the 9,9-dimethylfluorenylboronic acid ester is a monoboronic acid ester, the molar ratio of compound A, monoboronic acid ester and palladium catalyst is 1:(1-2):(0.1-0.2); when the 9,9-dimethylfluorenylboronic acid ester is a diboronic acid ester, the molar ratio of compound A, diboronic acid ester and palladium catalyst is (2-3):1:(0.05-0.2).

6. The preparation method according to claim 3, characterized in that, In step (3), the molar ratio of compound B or C to triethyl phosphite is 1:(30-32).

7. The preparation method according to claim 3, characterized in that, In step (4), the molar ratio of compound D or E to trimethylbromosilane is 1:(20-50).

8. The application of the carbazole-fluorene derivative self-assembled material according to claim 1 or 2 in the fabrication of optoelectronic devices.

9. The application according to claim 8, characterized in that, The optoelectronic device is a perovskite solar cell.

10. A perovskite solar cell, comprising a transparent conductive substrate, a hole transport layer or an interface modification layer, a perovskite light-absorbing layer, an electron transport layer, and a counter electrode stacked sequentially, characterized in that, The hole transport layer or interface modification layer comprises the carbazole-fluorene derivative self-assembled material as described in claim 1 or 2.

Images