Polymer material with side chain modified with phosphate group as well as preparation method and application of polymer material

Abstract

The invention discloses a polymer material with a side chain modified with a phosphate group and a preparation method and application of the polymer material, and belongs to the technical field of perovskite solar cells. The side chain modified phosphate group polymer material provided by the invention is simple in preparation method, has better film-forming property, can be used under an air condition, and is beneficial to large-area preparation of perovskite solar cell devices. The phosphate group is introduced into the side chain of the polymer, so that the dipole moment of the polymer is improved, and the hole transport capacity and the interface extraction capacity are improved. Besides, the polymer material with the side chain modified with the phosphate group has good metal oxide interface anchoring capability, and can effectively passivate a perovskite interface layer and inhibit ion migration when being applied to a perovskite solar cell device, so that the photoelectric conversion efficiency of the perovskite solar cell device is improved, and the photoelectric conversion efficiency of the perovskite solar cell device is improved. The method has important industrial application value.

Description

Technical Field

[0001] The present invention belongs to the technical field of perovskite solar cells, and relates to a polymer material with a side-chain modified phosphoric acid group, a preparation method thereof, and an application thereof. Background Art

[0002] Solar photovoltaics is a key renewable energy technology, and solar photovoltaic products are mainly based on single-crystalline silicon solar cells. Silicon-based solar cells still face huge technical and material challenges in improving power generation efficiency, reducing manufacturing energy consumption, and expanding application scenarios. Finding suitable photovoltaic technologies has become one of the tasks for further exploring the conversion of solar energy. Perovskite solar cells have shown extremely high commercial value in the photovoltaic market due to their advantages such as high photoelectric conversion efficiency, simple device structure, rich raw materials, low manufacturing cost, and flexibility.

[0003] Currently, there are still some key problems in this field, such as improving stability, large-area manufacturing, and efficiency decay. To solve the above problems, self-assembled monolayer (SAMs) materials have become one of the research hotspots in this field. SAMs materials have functions such as passivating the interface layer, inhibiting ion migration, enhancing interface stability, and improving charge transport, which can improve the stability and photoelectric conversion efficiency of devices. Most of the currently studied SAMs materials are single-molecule systems, while the research on polymer SAMs materials is relatively less. Compared with single-molecule SAMs, polymer SAMs have better film-forming properties and can achieve higher interface coverage when preparing devices with large areas.

[0004] The aromatic ring structures of existing polymer SAMs are all on the polymer main chain, and the dipole moment is weak. If some aromatic ring structures are placed on the side chain, theoretically, the molecular dipole moment can be increased, which is beneficial to the transport of interface charges. Based on this concept, the present invention designed and synthesized a series of polymer SAMs materials and applied them to perovskite solar cells, aiming to enrich the types of polymer SAMs materials and further improve device performance. Summary of the Invention

[0005] The present invention aims to solve the problems and defects existing in the above technologies. The present invention provides a polymer material with a side-chain modified phosphoric acid group, a preparation method thereof, and an application thereof. By introducing a phosphoric acid group into the side chain of the polymer, the dipole moment of the polymer is increased, the hole transport ability and interface extraction ability are improved, and it can be applied to perovskite solar cell devices to improve the photoelectric conversion efficiency of perovskite solar cells.

[0006] In the first aspect, the present invention provides a polymer material with a side-chain modified phosphoric acid group, having a structure shown in formula (1),

[0007]

[0008] Among them, R1 and R3 are selected from one of sulfur, oxygen, and isopropyl, or R1 and R3 do not exist, and the two benzene rings are directly connected or there is no connection;

[0009] R2 is selected from one of a benzene ring, furan, and thiophene, or R2 does not exist, and the main-chain nitrogen atom is directly connected to the side-chain benzene ring;

[0010] n represents the number of main-chain polymerization units;

[0011] m represents the length of the alkyl chain.

[0012] Furthermore, in the polymer material with side-chain modified phosphate groups provided by the present invention, the value range of n is 2 to 1,000,000.

[0013] Furthermore, in the polymer material with side-chain modified phosphate groups provided by the present invention, the value range of m is 2 to 10.

[0014] Furthermore, the polymer material with side-chain modified phosphate groups provided by the present invention has the following structure:

[0015]

[0016]

[0017]

[0018]

[0019] In the second aspect, the present invention provides a preparation method of a polymer material with side-chain modified phosphate groups, including Method 1 and Method 2:

[0020] When R2 does not exist and the main-chain nitrogen atom is directly connected to the side-chain benzene ring, Method 1 is adopted;

[0021] When R2 is selected from one of a benzene ring, furan, and thiophene, Method 2 is adopted.

[0022] Furthermore, in the preparation method of the polymer material with side-chain modified phosphate groups provided by the present invention, Method 1 includes:

[0023] S1. Under the action of a base, Reactant 1 reacts with a dibromo straight-chain alkane to generate Intermediate 1,

[0024]

[0025] Among them, X is selected from one of Br and I;

[0026] S2. The intermediate 1 and the reactant 2 are subjected to C-N coupling through the Ullmann or Buchwald-Hartwig reaction to generate intermediate 2.

[0027]

[0028] Wherein, X' is selected from one of Cl and Br.

[0029] S3. The intermediate 2 is heated under reflux under the action of triethyl phosphite to generate intermediate 3 containing a phosphoester functional group.

[0030]

[0031] S4. Intermediate 3 undergoes Yamamoto coupling under the catalysis of a nickel metal catalyst to generate intermediate 4.

[0032]

[0033] S5. Intermediate 4 reacts with a hydrolysis reagent to generate a polymer material with a side chain modified with a phosphate group.

[0034]

[0035] Furthermore, in the method for preparing the polymer material with a side chain modified with a phosphate group provided by the present invention, the base is selected from one of sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, and sodium hydride.

[0036] The nickel metal catalyst is selected from one of NiCl2(bipy), Ni(cod)2, NiBr2(PPh3)2, and NiCl2.

[0037] The hydrolysis reagent is trimethylsilyl bromide.

[0038] Furthermore, in the method for preparing the polymer material with a side chain modified with a phosphate group provided by the present invention, the method two includes:

[0039] S1. The same as S1 described in claim 6.

[0040] S2. Intermediate 1 reacts with bis(pinacolato)diboron under the action of a palladium catalyst to generate intermediate 5.

[0041]

[0042] Wherein, X is selected from one of Br and I.

[0043] S3. Intermediate 5 introduces an R2 aromatic ring with a halogen group through a suzuki coupling reaction to generate intermediate 6.

[0044]

[0045] S4. The same as S2 described in claim 6;

[0046] S5. The same as S3 described in claim 6;

[0047] S6. The same as S4 described in claim 6;

[0048] S7. The same as S5 described in claim 6.

[0049] In a third aspect, the present invention provides an application of a polymer material with a side-chain modified phosphoric acid group in a perovskite solar cell.

[0050] In a fourth aspect, the present invention provides a perovskite solar cell, comprising a conductive glass, a hole transport layer, a polymer self-assembled monolayer, a perovskite layer, an electron transport layer, a buffer layer, and a metal electrode, wherein the polymer self-assembled monolayer contains the polymer material with a side-chain modified phosphoric acid group.

[0051] Compared with the prior art, the technical solution provided by the present invention has at least the following beneficial effects or advantages:

[0052] The preparation method of the polymer material with a side-chain modified phosphoric acid group provided by the present invention is simple, has better film-forming performance, can be used under air conditions, and is beneficial to the large-area preparation of perovskite solar cell devices. By introducing a phosphoric acid group into the side chain of the polymer, the present invention improves the dipole moment of the polymer, enhances the hole transport ability and interface extraction ability. In addition, the polymer material with a side-chain modified phosphoric acid group of the present invention has good metal oxide interface anchoring ability. When applied to a perovskite solar cell device, it can effectively passivate the perovskite interface layer, inhibit ion migration, thereby improving the photoelectric conversion efficiency of the perovskite solar cell device, and has important industrial application value. Description of the Drawings

[0053] Figure 1 It is a schematic structural diagram of a perovskite solar cell device. Among them, 1 is a transparent conductive electrode (ITO); 2 is a hole transport layer (NiO X ); 3 is a polymer self-assembled monolayer; 4 is a perovskite layer (FA 0.85 MA 0.15 PbI3); 5 is an electron transport layer (C60); 6 is a buffer layer (SnO2); 7 is a metal electrode (Ag).

[0054] Figure 2 It is the J-V curve of a perovskite solar cell device with polymer 6 as the polymer self-assembled monolayer.

[0055] Figure 3J-V curve of the perovskite solar cell device with Polymer 12 as the polymer self-assembled monolayer.

[0056] Figure 4 J-V curve of the perovskite solar cell device with Polymer 38 as the polymer self-assembled monolayer.

[0057] Figure 5 J-V curve of the perovskite solar cell device with Polymer 64 as the polymer self-assembled monolayer.

[0058] Figure 6 J-V curve of the perovskite solar cell device with Polymer 100 as the polymer self-assembled monolayer. Detailed implementation manners

[0059] Next, the technical solutions of the present invention will be described in conjunction with the embodiments. However, the present invention is not limited to the following embodiments. The experimental methods and detection methods described in each embodiment are all conventional methods unless otherwise specified; the reagents and materials described are all commercially available unless otherwise specified.

[0060] The polymer with a side-chain modified phosphoric acid group involved in the present invention has a structure shown in formula (1):

[0061]

[0062] Among them, R1 and R3 are selected from bridging atoms such as sulfur and oxygen, or can also be bridging groups such as isopropyl groups, or may not exist, and the two benzene rings are directly connected or there is no connection;

[0063] R2 is selected from aromatic ring structures such as benzene rings, furans, and thiophenes, or may not exist, and the main-chain nitrogen atom is directly connected to the side-chain benzene ring.

[0064] Preparation examples

[0065] This preparation example provides the synthesis methods of some intermediates and compounds. The synthesis methods of the remaining intermediates and compounds are all similar methods and can be easily synthesized. The specific synthesis routes are shown as follows.

[0066] Synthesis of Polymer 6:

[0067] (1) Synthesis of Intermediate 6-1:

[0068]

[0069] Add 50 mL of toluene, 3-iodo-9H-carbazole (5.0 g, 17.1 mmol), tetrabutylammonium bromide (0.05 g, 0.16 mmol), and 1,2-dibromoethane (15.2 g, 80.0 mmol) into a 250 mL three-necked flask. Dropwise add 10 mL of aqueous sodium hydroxide solution (2.54 g, 63.52 mmol). After dropping, heat up to 60 °C and react for 24 h. Extract the reaction solution with ethyl acetate, wash it with water until neutral, and purify it by column chromatography to obtain 5.2 g of white solid of intermediate 6-1.

[0070] Mass spectrum of intermediate 6-1: C 14 H 11 BrIN, theoretical value: 400.06, measured value: 400.03. 1 1H NMR (400 MHz, DMSO-d6) δ 8.19–8.09 (m, 2H), 7.55 (dd, J = 7.7, 2.1 Hz, 1H), 7.51–7.46 (m, 2H), 7.36–7.27 (m, 2H), 4.41 (t, J = 2.4 Hz, 2H), 3.71 (t, J = 2.4 Hz, 2H).

[0071] (2) Synthesis of intermediate 6-2:

[0072]

[0073] Under argon protection, add intermediate 6-1 (5.2 g, 13.0 mmol), 4,4'-dibromodiphenylamine (4.68 g, 14.3 mmol), CuCl (0.38 g, 3.8 mmol), KOH (2.0 g, 35.6 mmol), 1,10-phenanthroline monohydrate (0.75 g, 3.8 mmol), and 100 mL of toluene into a 250 mL three-necked flask. Heat under reflux for 24 h. Extract the reaction solution with ethyl acetate, wash it with water until neutral, and purify it by column chromatography to obtain 6.2 g of white solid of intermediate 6-2.

[0074] Mass spectrum of intermediate 6-2: C 26 H 19 Br3N2, theoretical value: 599.16, measured value: 599.23. 1 1H NMR (400 MHz, DMSO-d6) δ 8.15 (d, J = 7.8 Hz, 1H), 7.62–7.54 (m, 2H), 7.53–7.40 (m, 6H), 7.37–7.27 (m, 1H), 7.22–7.14 (m, 5H), 4.42 (t, J = 2.4 Hz, 2H), 3.71 (t, J = 2.4 Hz, 2H).

[0075] (3) Synthesis of intermediate 6-3

[0076]

[0077] Add intermediate 6-2 (5.0 g, 8.3 mmol) and triethyl phosphite (16.6 g, 100 mmol) to a 100 mL three-necked flask, and heat up to 140 °C for reaction for 5 h. After the reaction is completed, directly distill off the remaining triethyl phosphite under reduced pressure to obtain intermediate 6-3 as a brown viscous liquid (5.2 g, 7.9 mmol).

[0078] Mass spectrum of intermediate 6-3: C 30 H 29 O3Br2N2P, theoretical value: 656.35, measured value: 656.73. 1 1H NMR (400 MHz, DMSO-d6) δ 8.15 (d, J = 7.8 Hz, 1H), 7.62–7.55 (m, 2H), 7.52–7.40 (m, 6H), 7.37–7.27 (m, 1H), 7.22–7.14 (m, 5H), 4.27 (t, J = 7.1 Hz, 2H), 3.88 (dq, J = 8.5, 7.1 Hz, 4H), 2.45–2.34 (m, 2H), 1.34–1.26 (m, 6H).

[0079] (4) Synthesis of intermediate 6-4:

[0080]

[0081] Under argon protection, add intermediate 6-3 (2.0 g, 3.0 mmol) to a 100 mL three-necked flask, add 25 mL of dry DMF to dissolve until clear. After refluxing to remove oxygen for 10 min, cool down to room temperature, add Ni(cod)2 (0.83 g, 3.0 mmol) and 2,2'-bipyridine (0.47 g, 3.0 mmol), and react at 85 °C for 24 h. Naturally cool to room temperature, add 1 mL of dilute hydrochloric acid aqueous solution, extract with dichloromethane for several times, combine the organic phases, concentrate under reduced pressure until the volume of the organic phase is about 10 mL, add about 100 mL of diethyl ether, and filter to obtain 1.2 g of intermediate 6-4 as an off-white solid. Gel permeation chromatography (GPC) test shows that Mw > 3000.

[0082] (5) Synthesis of polymer 6:

[0083]

[0084] At room temperature, add intermediate 6-4 (1.0 g) to a 100 mL three-necked flask, add 10 mL of dichloromethane to dissolve it clearly, add trimethylsilyl bromide (1.5 g, 10 mmol), stir at room temperature overnight, pour the reaction solution into 200 mL of methanol, stir for 30 min, and filter to obtain 0.7 g of off-white solid polymer 6.

[0085] Synthesis of polymer 12:

[0086] (1) Synthesis of intermediate 12-1:

[0087]

[0088] To a 250mL three-necked flask, add 50mL of toluene, 2-bromo-9,9-dimethyl-9,10-dihydroacridine (5.0g, 17.4mmol), tetrabutylammonium bromide (0.05g, 0.16mmol), 1,2-dibromobutane (15.0g, 80.2mmol), and dropwise add 10mL of sodium hydroxide aqueous solution (2.54g, 63.52mmol). After the dropwise addition, heat to 60°C and react for 24h. The reaction solution is extracted with ethyl acetate, washed with water until neutral, and separated and purified by column chromatography to obtain 4.7g of intermediate 12-1 as a white solid.

[0089] Mass spectrum of intermediate 12-1: C 17 H 17 Br2N, theoretical value: 395.14, measured value: 395.23. 1 H NMR (400MHz, DMSO-d6) δ7.36(dd,J=8.2,2.1Hz,1H),7.30(d,J=2.2Hz,1H),7.20(t,J=6.7Hz,2H) ,7.10–7.01(m,1H),6.91–6.83(m,2H),4.07(t,J=4.6Hz,2H),3.70(t,J=4.6Hz,2H),1.57(s,6H).

[0090] (2) Synthesis of intermediate 12-2:

[0091]

[0092] Under argon protection, intermediate 12-1 (4.5 g, 11.4 mmol), 3,6-dibromocarbazole (3.9 g, 12.0 mmol), sodium tert-butoxide (1.2 g, 12.5 mmol), and 100 mL of toluene were added to a 250 mL three-necked flask, and the mixture was heated to reflux and deoxygenated for 30 min. After cooling to room temperature, Pd2(dba)3 (0.11 g, 0.12 mmol) and tri-tert-butylphosphine tetrafluoroborate (35 mg, 0.12 mmol) were added, and the mixture was refluxed for 12 h. The mixture was cooled to room temperature, and the reaction solution was extracted with ethyl acetate, washed with water until neutral, and separated and purified by column chromatography to obtain 4.2 g of intermediate 12-2 as a white solid.

[0093] Mass spectrum of intermediate 12-2: C 29 H 23 Br3N2, theoretical value: 639.23, measured value: 639.18. 1 H NMR (400MHz, DMSO-d6) δ8.41(d,J=2.4Hz,1H),8.25(d,J=2.7Hz,1H),7.78(d,J=8.0Hz,1H),7.73–7.66(m,1H),7.51–7.41(m,3H),7.25–7.16( m,2H),7.12(dd,J=6.5,2.1Hz,1H),7.09–7.01(m,2H),6.93(dd,J=6.3,1.4Hz,1H),4.07(t,J=4.6Hz,2H),3.70(t,J=4.6Hz,2H),1.57(s,6H).

[0094] (3) Synthesis of intermediate 12-3:

[0095]

[0096] The synthesis method is the same as that of intermediate 6-3 to obtain 4.3 g of intermediate 12-3 as an off-white solid.

[0097] Mass spectrum of intermediate 12-3: C 33 H 33 O3Br2N2P, theoretical value: 696.42, measured value: 696.38. 11H NMR (400 MHz, DMSO-d6) δ 8.41 (d, J = 2.4 Hz, 1H), 8.25 (d, J = 2.7 Hz, 1H), 7.78 (d, J = 8.0 Hz, 1H), 7.73–7.66 (m, 1H), 7.51–7.41 (m, 3H), 7.25–7.16 (m, 2H), 7.15–7.01 (m, 3H), 6.93 (dd, J = 6.3, 1.4 Hz, 1H), 4.10 (t, J = 7.6 Hz, 2H), 3.88 (dq, J = 8.5, 7.1 Hz, 4H), 2.43–2.32 (m, 2H), 1.57 (s, 6H), 1.34–1.26 (m, 6H).

[0098] (4) Synthesis of Intermediate 12-4

[0099]

[0100] The synthesis method was the same as that of Intermediate 6-4, and 3.7 g of off-white solid of Intermediate 12-4 was obtained. Gel permeation chromatography (GPC) test showed that Mw > 16000.

[0101] (5) Synthesis of Compound 12:

[0102]

[0103] The synthesis method was the same as that of Polymer 6. The addition amount of Intermediate 12-4 was 3.0 g, and 2.2 g of off-white solid of Polymer 12 was obtained.

[0104] Synthesis of Polymer 38:

[0105] (1) Synthesis of Intermediate 38-1:

[0106]

[0107] Add 50 mL of toluene, 3-bromocarbazole (5.0 g, 20.3 mmol), tetrabutylammonium bromide (0.05 g, 0.16 mmol), and 1,4-dibromobutane (18.0 g, 83.4 mmol) into a 250 mL three-necked flask. Dropwise add 10 mL of sodium hydroxide aqueous solution (2.54 g, 63.52 mmol). After dropping, heat up to 60 °C and react for 24 h. The reaction solution was extracted with ethyl acetate, washed with water until neutral, and purified by column chromatography to obtain 5.8 g of white solid of Intermediate 38-1.

[0108] Mass spectrum of Intermediate 38-1: C 16 H 15 Br2N, theoretical value: 381.11, measured value: 380.87. 11H NMR (400 MHz, DMSO-d6) δ 8.19–8.08 (m, 2H), 7.90 (dd, J = 6.5, 1.3 Hz, 1H), 7.53–7.41 (m, 2H), 7.39–7.28 (m, 2H), 4.19 (t, J = 5.5 Hz, 2H), 3.57 (s, 2H), 1.92 (ttd, J = 6.8, 3.9, 1.1 Hz, 2H), 1.86–1.75 (m, 2H).

[0109] (2) Synthesis of Intermediate 38-2:

[0110]

[0111] Under argon protection, 50 mL of toluene, Intermediate 38-1 (5.0 g, 13.1 mmol), potassium acetate (1.9 g, 19.4 mmol), and bis(pinacolato)diboron (6.6 g, 26.0 mmol) were added to a 250 mL three-necked flask. The mixture was heated under reflux to expel oxygen for 30 min. After cooling to room temperature, Pd(dppf)Cl2 (95 mg, 0.13 mmol) was added, and the mixture was refluxed for 24 h. Then it was cooled to room temperature, extracted with ethyl acetate, washed with water until neutral, and purified by column chromatography to obtain 4.6 g of pale yellow solid of Intermediate 38-2.

[0112] MS of Intermediate 38-2: C 22 H 27 O2BBrN, theoretical value: 428.46, measured value: 428.18. 1 1H NMR (400 MHz, DMSO-d6) δ 8.14 (dd, J = 7.8, 1.2 Hz, 1H), 8.06 (d, J = 2.2 Hz, 1H), 7.90 (dd, J = 6.5, 1.3 Hz, 1H), 7.59 (dd, J = 7.3, 2.2 Hz, 1H), 7.53–7.45 (m, 2H), 7.37–7.28 (m, 1H), 4.19 (t, J = 5.5 Hz, 2H), 3.57 (s, 2H), 1.97–1.86 (m, 2H), 1.86–1.75 (m, 2H), 1.28 (s, 12H).

[0113] (3) Synthesis of Intermediate 38-3

[0114]

[0115] Under argon protection, 50 mL of toluene, intermediate 38-2 (4.0 g, 9.3 mmol), p-diiodobenzene (4.6 g, 14.0 mmol), and potassium carbonate (2.0 g, 14.5 mmol) were added to a 250 mL three-necked flask. After refluxing to remove oxygen for 30 min, the temperature was cooled to room temperature, and Pd(PPh3)4 (0.1 g, 0.09 mmol) was added. The mixture was heated under reflux for 6 h, then cooled to room temperature. It was extracted with ethyl acetate, washed with water until neutral, and purified by column chromatography to obtain 3.7 g of pale yellow solid of intermediate 38-3.

[0116] Mass spectrum of intermediate 38-3: C 22 H 19 BrIN, theoretical value: 504.21, measured value: 504.77. 1 1H NMR (400 MHz, DMSO-d6) δ 8.18–8.09 (m, 2H), 7.90 (dd, J = 6.5, 1.3 Hz, 1H), 7.76–7.69 (m, 3H), 7.56 (d, J = 6.8 Hz, 1H), 7.53–7.48 (m, 1H), 7.48–7.42 (m, 2H), 7.37–7.28 (m, 1H), 4.19 (t, J = 5.5 Hz, 2H), 3.57 (s, 2H), 1.97–1.86 (m, 2H), 1.86–1.75 (m, 2H).

[0117] (4) Synthesis of intermediate 38-4:

[0118]

[0119] Under argon protection, 100 mL of toluene, intermediate 38-3 (3.5 g, 6.9 mmol), 2,7-dibromo-9,9-dimethylacridine (3.8 g, 10.2 mmol), and sodium tert-butoxide (1.0 g, 10.4 mmol) were added to a 250 mL three-necked flask. After refluxing to remove oxygen for 30 min, the temperature was cooled to room temperature, and Pd2(dba)3 (0.11 g, 0.12 mmol) and X-Phos (2-dicyclohexylphosphino-2′,4′,6′-triisopropylbiphenyl, 57 mg, 0.12 mmol) were added. The mixture was heated under reflux for 2 h, then cooled to room temperature. It was extracted with ethyl acetate, washed with water until neutral, and purified by column chromatography to obtain 2.7 g of yellow solid of intermediate 38-4.

[0120] Mass spectrum of intermediate 38-4: C 37 H 31 Br3N2, theoretical value: 743.38, measured value: 743.67. 11H NMR (400 MHz, DMSO-d6) δ 8.15 (dd, J = 7.8, 1.2 Hz, 1H), 8.07 (d, J = 2.4 Hz, 1H), 7.90 (dd, J = 6.5, 1.3 Hz, 1H), 7.61–7.28 (m, 10H), 7.20–7.13 (m, 2H), 6.98 (d, J = 8.0 Hz, 2H), 4.19 (t, J = 5.5 Hz, 2H), 3.57 (s, 2H), 1.97–1.86 (m, 2H), 1.86–1.75 (m, 2H), 1.56 (s, 6H).

[0121] (5) Synthesis of Intermediate 38-5:

[0122]

[0123] The synthesis method is the same as that of Intermediate 6-3. The addition amount of Intermediate 38-4 is 2.2 g, and 1.4 g of yellow solid of Intermediate 38-5 is obtained.

[0124] MS of Intermediate 38-5: C 41 H 41 O3Br2N2P, theoretical value: 800.57, measured value: 799.93. 1 1H NMR (400 MHz, DMSO-d6) δ 8.15 (dd, J = 7.8, 1.2 Hz, 1H), 8.07 (d, J = 2.4 Hz, 1H), 7.90 (dd, J = 6.5, 1.3 Hz, 1H), 7.62–7.28 (m, 10H), 7.19–7.11 (m, 2H), 6.98 (d, J = 8.1 Hz, 2H), 4.14 (t, J = 5.2 Hz, 2H), 3.99 (dq, J = 8.5, 7.2 Hz, 4H), 1.99–1.85 (m, 2H), 1.79 (tt, J = 6.5, 5.0 Hz, 2H), 1.68–1.57 (m, 2H), 1.56 (s, 6H), 1.34–1.26 (m, 6H).

[0125] (6) Synthesis of Intermediate 38-6:

[0126]

[0127] The synthesis method is the same as that of Intermediate 6-4. The addition amount of Intermediate 38-5 is 1.2 g, and 0.8 g of yellow solid of Intermediate 38-6 is obtained. Gel permeation chromatography (GPC) test shows that Mw > 4000.

[0128] (7) Synthesis of Polymer 38:

[0129]

[0130] The synthesis method is the same as that of Polymer 6. 0.5 g of Intermediate 38-6 was used as the feedstock to obtain 0.2 g of pale yellow solid of Polymer 38.

[0131] Synthesis of Polymer 64:

[0132] (1) Synthesis of Intermediate 64-1:

[0133]

[0134] Under argon protection, 100 mL of toluene, Intermediate 38-2 (4.0 g, 9.3 mmol), 2,5-dibromofuran (3.2 g, 14.2 mmol), and potassium carbonate (2.0 g, 14.5 mmol) were added to a 250 mL three-necked flask. After refluxing to remove oxygen for 30 min, the temperature was lowered to room temperature, and then Pd(PPh3)4 (0.1 g, 0.09 mmol) was added. The mixture was heated under reflux for 6 h, cooled to room temperature, extracted with ethyl acetate, washed with water until neutral, and purified by column chromatography to obtain 2.4 g of off-white solid of Intermediate 64-1.

[0135] Mass spectrum of Intermediate 64-1: C 20 H 17 OBr2N, theoretical value: 447.17, measured value: 447.21. 1 1H NMR (400 MHz, DMSO-d6) δ 8.19–8.08 (m, 2H), 7.89 (dt, J = 6.6, 1.8 Hz, 2H), 7.54–7.45 (m, 2H), 7.37–7.28 (m, 1H), 7.05 (d, J = 5.6 Hz, 1H), 6.71 (d, J = 5.4 Hz, 1H), 4.19 (t, J = 5.5 Hz, 2H), 3.57 (s, 2H), 1.97–1.86 (m, 2H), 1.86–1.75 (m, 2H).

[0136] (2) Synthesis of Intermediate 64-2:

[0137]

[0138] Under argon protection, 100 mL of toluene, 2.0 g (4.5 mmol) of intermediate 64-1, 1.7 g (5.0 mmol) of 3,7-dibromophenoxazine, and 0.5 g (5.2 mmol) of sodium tert-butoxide were added into a 250 mL three-necked flask. The mixture was refluxed for 30 min to remove oxygen. After cooling to room temperature, 46 mg (0.05 mmol) of Pd2(dba)3 and 30 mg (0.06 mmol) of X-Phos were added. The reaction mixture was heated under reflux for 2 h, then cooled to room temperature, extracted with ethyl acetate, washed with water until neutral, and purified by column chromatography to obtain 1.1 g of off-white solid of intermediate 64-2.

[0139] Mass spectrum of intermediate 64-2: C 32 H 23 O2Br3N2, theoretical value: 707.26, measured value: 707.63. 1 1H NMR (400 MHz, DMSO-d6) δ 8.19–8.12 (m, 1H), 8.09 (d, J = 2.4 Hz, 1H), 7.93–7.83 (m, 2H), 7.53–7.45 (m, 2H), 7.43–7.28 (m, 5H), 7.01 (d, J = 0.7 Hz, 2H), 6.90 (d, J = 2.2 Hz, 2H), 4.19 (t, J = 5.5 Hz, 2H), 3.57 (s, 2H), 1.97–1.86 (m, 2H), 1.86–1.75 (m, 2H).

[0140] (3) Synthesis of intermediate 64-3:

[0141]

[0142] The synthesis method was the same as that of intermediate 6-3. 1.0 g of intermediate 64-2 was used as the starting material to obtain 0.9 g of off-white solid of intermediate 64-3.

[0143] Mass spectrum of intermediate 64-3: C 36 H 33 O5Br2N2P, theoretical value: 764.45, measured value: 764.50. 11H NMR (400 MHz, DMSO-d6) δ 8.19–8.12 (m, 1H), 8.09 (d, J = 2.4 Hz, 1H), 7.93–7.83 (m, 2H), 7.53–7.45 (m, 2H), 7.43–7.28 (m, 5H), 7.01 (d, J = 0.7 Hz, 2H), 6.90 (d, J = 2.2 Hz, 2H), 4.14 (t, J = 5.2 Hz, 2H), 3.99 (dq, J = 8.5, 7.2 Hz, 4H), 1.98–1.86 (m, 2H), 1.79 (tt, J = 6.5, 5.1 Hz, 2H), 1.68–1.56 (m, 2H), 1.34–1.26 (m, 6H).

[0144] (4) Synthesis of intermediate 64-4:

[0145]

[0146] The synthesis method is the same as that of intermediate 6-4. 0.6 g of intermediate 64-3 was used as starting material to obtain 0.2 g of intermediate 64-4 as a yellow solid. Gel permeation chromatography (GPC) test showed that Mw > 4000.

[0147] (5) Synthesis of polymer 64:

[0148]

[0149] The synthesis method is the same as that of polymer 6. 0.2 g of intermediate 64-4 was used as starting material to obtain 72 mg of polymer 64 as a gray solid.

[0150] Synthesis of polymer 100:

[0151] (1) Synthesis of intermediate 100-1:

[0152]

[0153] The synthesis method is the same as that of intermediate 38-1. 5 g (19.1 mmol) of 3-bromo-10H-phenoxazine was used as starting material to obtain 5.2 g of intermediate 100-1 as a white solid.

[0154] Mass spectrum of intermediate 100-1: C 16 H 15 OBr2N, theoretical value: 397.11, measured value: 397.13. 11H NMR (400 MHz, DMSO-d6) δ 7.33 (dd, J = 8.8, 2.2 Hz, 1H), 7.28–7.07 (m, 4H), 6.90–6.79 (m, 2H), 3.84 (t, J = 5.8 Hz, 2H), 3.55 (s, 2H), 1.97–1.86 (m, 2H), 1.80–1.69 (m, 2H).

[0155] (2) Synthesis of Intermediate 100-2:

[0156]

[0157] The synthesis method was the same as that of Intermediate 38-2. 5 g (12.6 mmol) of Intermediate 100-1 was used as starting material to obtain 4.3 g of white solid Intermediate 100-2.

[0158] Mass spectrum of Intermediate 100-2: C 22 H 27 O3BBrN, theoretical value: 444.18, measured value: 444.13. 1 1H NMR (400 MHz, DMSO-d6) δ 7.39 (dd, J = 7.8, 2.2 Hz, 1H), 7.28–7.19 (m, 2H), 7.19–7.08 (m, 2H), 7.02 (d, J = 7.8 Hz, 1H), 6.83 (dd, J = 8.1, 1.2 Hz, 1H), 3.84 (t, J = 5.8 Hz, 2H), 3.55 (s, 2H), 1.97–1.86 (m, 2H), 1.80–1.69 (m, 2H), 1.28 (s, 12H).

[0159] (3) Synthesis of Intermediate 100-3:

[0160]

[0161] Under argon protection, 100 mL of toluene, 4.0 g (9.0 mmol) of Intermediate 100-2, 3.5 g (14.5 mmol) of 2,5-dibromothiophene, and 2.0 g (14.5 mmol) of potassium carbonate were added to a 250 mL three-necked flask. The mixture was refluxed for 30 min to remove oxygen, cooled to room temperature, then 0.1 g (0.09 mmol) of Pd(PPh3)4 was added, and the mixture was heated under reflux for 6 h. After cooling to room temperature, it was extracted with ethyl acetate, washed with water until neutral, and purified by column chromatography to obtain 2.7 g of yellow solid Intermediate 100-3.

[0162] Mass spectrum of Intermediate 100-3: C 20 H 17 OBr2NS, theoretical value: 479.23, measured value: 479.21.1 1H NMR (400 MHz, DMSO-d6) δ 7.65 (dd, J = 7.2, 1.8 Hz, 1H), 7.28–7.19 (m, 2H), 7.16 (dd, J = 7.1, 1.2 Hz, 1H), 7.14–7.06 (m, 3H), 7.02 (d, J = 6.8 Hz, 1H), 6.84 (dd, J = 8.1, 1.2 Hz, 1H), 3.84 (t, J = 5.8 Hz, 2H), 3.55 (s, 2H), 1.97–1.86 (m, 2H), 1.80–1.69 (m, 2H).

[0163] (4) Synthesis of Intermediate 100-4:

[0164]

[0165] Under argon protection, add 100 mL of toluene, Intermediate 100-3 (2.5 g, 5.2 mmol), 3,7-dibromophenothiazine (2.6 g, 7.3 mmol), and sodium tert-butoxide (0.7 g, 7.3 mmol) into a 250 mL three-necked flask. Reflux for 30 min to remove oxygen, cool to room temperature, then add Pd2(dba)3 (46 mg, 0.05 mmol) and X-Phos (30 mg, 0.06 mmol). Heat under reflux for 2 h, cool to room temperature, extract with ethyl acetate, wash with water until neutral, and purify by column chromatography to obtain 1.6 g of orange solid of Intermediate 100-4.

[0166] Mass spectrum of Intermediate 100-4: C 32 H 23 OBr3N2S2, theoretical value: 755.59, measured value: 755.38. 1 1H NMR (400 MHz, DMSO-d6) δ 7.49–7.42 (m, 4H), 7.33 (dt, J = 8.8, 1.2 Hz, 2H), 7.28–7.19 (m, 3H), 7.15 (td, J = 7.2, 1.2 Hz, 1H), 7.13–7.04 (m, 2H), 6.87–6.81 (m, 2H), 6.35 (d, J = 6.1 Hz, 1H), 3.84 (t, J = 5.8 Hz, 2H), 3.55 (s, 2H), 1.97–1.86 (m, 2H), 1.80–1.69 (m, 2H).

[0167] (5) Synthesis of Intermediate 100-5:

[0168]

[0169] The synthesis method is the same as that of intermediate 6-3. 1.5 g (2.0 mmol) of intermediate 100-4 was used as starting material to obtain 0.7 g of intermediate 100-5 as an orange-red solid.

[0170] MS of intermediate 100-5: C 36 H 33 O4Br2N2PS2, theoretical value: 811.83, measured value: 811.91. 1 1H NMR (400 MHz, DMSO-d6) δ 7.49–7.42 (m, 4H), 7.33 (dt, J = 8.8, 1.2 Hz, 2H), 7.28–7.21 (m, 2H), 7.21–7.13 (m, 2H), 7.13–7.04 (m, 2H), 6.87–6.81 (m, 2H), 6.35 (d, J = 6.1 Hz, 1H), 3.99 (dq, J = 8.5, 7.2 Hz, 4H), 3.86 (t, J = 5.2 Hz, 2H), 1.98–1.86 (m, 2H), 1.75–1.55 (m, 4H), 1.34–1.26 (m, 6H).

[0171] (6) Synthesis of intermediate 100-6:

[0172]

[0173] The synthesis method is the same as that of intermediate 6-4. 0.5 g (0.6 mmol) of intermediate 100-5 was used as starting material to obtain 0.2 g of intermediate 100-6 as a brown solid. Gel permeation chromatography (GPC) test showed Mw > 6000.

[0174] (7) Synthesis of polymer 100:

[0175]

[0176] The synthesis method is the same as that of polymer 6. 0.2 g of intermediate 100-6 was used as starting material to obtain 80 mg of polymer 100 as a brown solid.

[0177] Example 1

[0178] In this example, the polymer with a side-chain modified phosphate group prepared in the preparation example was used as the material for the polymer self-assembled monolayer (SAM layer), and combined with other functional layers of the perovskite solar cell to make a device. As Figure 1 shown, the device includes, from bottom to top: conductive glass (ITO); hole transport layer (NiO x ); polymer self-assembled monolayer; perovskite layer (FA 0.85 MA 0.15(PbI3); Electron transport layer (C60); Buffer layer (SnO2); Metal electrode (Ag). Among them, the effective area of a single device is about 0.25 cm 2 , NiO x The NiO layer is prepared by magnetron sputtering, the polymer self-assembled monolayer is prepared by spin coating, the perovskite layer is prepared by spin coating, C60 is prepared by vacuum evaporation, SnO2 is prepared by magnetron sputtering, and the Ag electrode is prepared by vacuum evaporation.

[0179] Polymers 6, 12, 38, 64, and 100 are used as SAM layer materials, and the performance of perovskite solar cell devices is tested. Under AM1.5G, 100 mW / cm 2 The J-V performance curves of perovskite solar cells are tested under illumination, and the following parameters are obtained: open circuit voltage (Voc), short circuit current density (Jsc), fill factor (FF), and photoelectric conversion efficiency (PCE). The test results are shown in Table 1 below.

[0180] Comparative Example 1

[0181] This comparative example is the same as Example 1, except that the SAM layer material in this comparative example is Poly-4PACz.

[0182] Table 1 Performance test results of perovskite solar cell devices

[0183]

[0184] Figure 2 is the J-V curve of a perovskite solar cell device prepared with Polymer 6 as the SAM layer material; Figure 3 is the J-V curve of a perovskite solar cell device prepared with Polymer 12 as the SAM layer material; Figure 4 is the J-V curve of a perovskite solar cell device prepared with Polymer 38 as the SAM layer material; Figure 5 is the J-V curve of a perovskite solar cell device prepared with Polymer 64 as the SAM layer material; Figure 6The J-V curve of the perovskite solar cell device prepared with Polymer 100 as the SAM layer material. The core measurement standard for the quality of perovskite solar cell performance lies in its photoelectric conversion efficiency (PEC). The photoelectric conversion efficiency is mainly determined by FF (fill factor), Voc (open-circuit voltage), and Jsc (short-circuit current). The Voc of the perovskite cell is mainly determined by the difference between the Fermi energy level of the perovskite light-absorbing layer and the highest occupied molecular orbital (HOMO) of the hole transport layer. However, Voc is not only strictly restricted by the bandgap of the perovskite itself, but also inevitably suffers energy losses during the charge transport process. This requires the perovskite material to have an appropriate bandgap to avoid too low short-circuit current while maintaining a relatively high open-circuit voltage, thereby ensuring the overall performance of the battery. Based on the above principle, in the present invention, a polymer self-assembled monolayer is introduced between the hole transport layer and the perovskite layer, significantly improving the interfacial contact between the perovskite layer and the hole transport layer, effectively reducing the charge recombination phenomenon between the hole transport layer and the electron transport layer, and thus greatly increasing the fill factor. As can be seen from Table 1, when the polymer provided by the present invention is used as the SAM layer of the perovskite solar cell, the fill factor of the solar cell is increased by 1.33% - 5.5%, and the photoelectric conversion efficiency is increased by 0.22% - 3.13%. The improvement effect on the performance of the perovskite solar cell device is obvious, indicating that the polymer self-assembled monolayer material of the present invention has the advantages of modifying the interfacial layer, enhancing the hole transport ability, increasing the open-circuit voltage and fill factor, and improving the photoelectric conversion efficiency. The present invention provides strong technical support for the development of perovskite solar cells and has broad application prospects.

[0185] The above-described embodiments are some, but not all, of the embodiments of the present invention. The detailed description of the embodiments of the present invention is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. All other embodiments obtained by relevant deductions and substitutions made by those of ordinary skill in the art under the premise of not making creative efforts based on the concept of the present invention fall within the scope of protection of the present invention.

Claims

1. A polymer material with a side chain modified with a phosphate group, characterized in that: Having the structure shown in formula (1), wherein R1, R3 are selected from one of sulfur, oxygen, and isopropyl, or R1, R3 do not exist, and the two benzene rings are directly connected or not connected; R2 is selected from a benzene ring, furan, thiophene, or R2 does not exist, and the main chain nitrogen atom is directly connected to the side chain benzene ring; n represents the number of main chain polymerization units; m represents the alkyl chain length.

2. The polymer material with side chain modified phosphate groups according to claim 1, characterized in that: The value range of n is 2 to 1,000,000.

3. The polymer material with side chain modified phosphate groups according to claim 1, characterized in that: The value range of m is 2-10.

4. The polymer material with side chain modified phosphate groups according to claim 1, characterized in that: Has the following structure:

5. The method for preparing a polymer material having a side chain modified with a phosphate group according to any one of claims 1 to 4, characterized in that: Including method one and method two: When R2 does not exist and the main chain nitrogen atom is directly connected to the side chain benzene ring, the method 1 is adopted; When R2 is selected from a benzene ring, furan, and thiophene, the method 2 is adopted.

6. The preparation method according to claim 5, characterized in that: The method 1 comprises: S1. Under the action of a base, reactant 1 reacts with dibromo straight-chain alkane to generate intermediate 1. Wherein, X is selected from one of Br and I; S2. CN coupling of intermediate 1 and reactant 2 is carried out by Ullmann or Buchwald-Hartwig reaction to generate intermediate 2. Wherein, X' is selected from one of Cl and Br; S3. The intermediate 2 is heated to reflux under the action of triethyl phosphite to generate an intermediate 3 containing a phosphorus ester functional group, S4. Intermediate 3 undergoes Yamamoto coupling under the catalysis of nickel metal catalyst to generate intermediate 4. S5. Intermediate 4 reacts with a hydrolysis agent to generate a polymer material with a side chain modified with a phosphate group, 7. The preparation method according to claim 6, characterized in that: The base is selected from one of sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate and sodium hydride; The nickel metal catalyst is selected from one of NiCl2(bipy), Ni(cod)2, NiBr2(PPh3)2, and NiCl2; The hydrolysis agent is trimethylsilyl bromide.

8. The preparation method according to claim 5, characterized in that: The second method comprises: S1. The same as S1 described in claim 6; S2. Intermediate 1 reacts with diboric acid pinacol ester under the action of palladium catalyst to generate intermediate 5. Wherein, X is selected from one of Br and I; S3. Intermediate 5 is subjected to a Suzuki coupling reaction to introduce an aromatic ring R2 with a halogen group to generate intermediate 6. S4. The same as S2 described in claim 6; S5. The same as S3 described in claim 6; S6. The same as S4 described in claim 6; S7. The same as S5 described in claim 6.

9. Use of the polymer material with side chain modified phosphate groups according to any one of claims 1 to 4 in perovskite solar cells.

10. A perovskite solar cell, comprising conductive glass, a hole transport layer, a polymer self-assembled monolayer, a perovskite layer, an electron transport layer, a buffer layer and a metal electrode, characterized in that: The polymer self-assembled monolayer contains the polymer material with side chain modified phosphate groups according to any one of claims 1 to 4.

Images