Benzyl phosphorous acid grafted thiophene polymer material and application thereof

Abstract

The invention discloses a benzyl phosphorous acid grafted thiophene polymer material and application thereof. The benzyl phosphorous acid grafted thiophene polymer material comprises a benzyl phosphorous acid grafted thiophene polymer, the structural formula of the benzyl phosphorous acid substituted thiophene polymer is as shown in the formula (I), the benzyl phosphorous acid grafted thiophene polymer material is used for preparing the perovskite solar cell, and the prepared perovskite solar cell has relatively high cell energy conversion efficiency, can keep relatively high cell conversion efficiency in environments with different humidity, and is high in stability.

Description

Technical Field

[0001] This invention belongs to the field of grafted polymer technology, and particularly relates to a thiophene polymer material grafted with benzyl phosphorous acid and its application. Background Technology

[0002] In recent years, to address the increasingly severe energy and environmental problems, people have turned their attention to the development and utilization of new energy sources. Among various new energy technologies, solar power generation is undoubtedly one of the most promising directions. Among the many new types of solar cells, perovskite solar cells have stood out in the past two years due to their advantages such as low raw material prices, simple production processes, ability to be fabricated on flexible substrates, and the ability to be fabricated on a large area using methods such as coating and printing.

[0003] However, existing perovskite solar cells are prone to decomposition and have poor stability, making it difficult to maintain high cell conversion efficiency under different humidity environments. This affects the application of perovskite solar cells in different regions and limits their development. Summary of the Invention

[0004] To address the shortcomings of the prior art, this invention provides a benzyl phosphorous acid-grafted thiophene polymer material and its application. This invention uses the benzyl phosphorous acid-grafted thiophene polymer material to prepare perovskite solar cells. The prepared perovskite solar cells have high energy conversion efficiency, can maintain high energy conversion efficiency under different humidity environments, and have high stability.

[0005] The purpose of this invention is to provide a benzyl phosphorous acid-grafted thiophene polymer, wherein the structural formula of the benzyl phosphorous acid-substituted thiophene polymer is shown in formula (I):

[0006] Equation (Ⅰ);

[0007] Among them, the number-average molecular weight is 5-51 kDa, and the molecular weight distribution index (PDI) is 3.0-3.5.

[0008] In some embodiments of the present invention, the number-average molecular weight of the thiophene polymer grafted with benzylphosphite is 16.6~19.1 kDa, and the molecular weight distribution index (PDI) is 3.1~3.2.

[0009] Another object of the present invention is to provide a benzyl phosphorous acid-grafted thiophene polymer material, comprising the benzyl phosphorous acid-grafted thiophene polymer, and the preparation method thereof includes the following steps:

[0010] S1. Poly(3-hexylthiophene) reacts with diethyl 4-bromobenzyl phosphite to obtain a thiophene polymer material substituted with diethyl benzyl phosphite;

[0011] S2. Phosphorylate the thiophene polymer material substituted with diethyl benzyl phosphite to obtain the thiophene polymer material grafted with benzyl phosphite.

[0012] In some embodiments of the present invention, in S1, the raw materials for the reaction further include a catalyst and an auxiliary agent.

[0013] In some embodiments of the present invention, the catalyst is selected from palladium chloride.

[0014] In some embodiments of the present invention, the adjuvant includes an organophosphorus ligand, an inorganic base, an organic acid, and a first solvent.

[0015] In some embodiments of the present invention, the organophosphorus ligand comprises triphenylphosphine.

[0016] In some embodiments of the present invention, the inorganic base includes potassium carbonate.

[0017] In some embodiments of the present invention, the organic acid includes tervastatin.

[0018] In some embodiments of the present invention, the first solvent includes toluene.

[0019] In some embodiments of the present invention, in S1, the molar ratio of poly(3-hexylthiophene) to diethyl 4-bromobenzyl phosphite is 1:0.3~1.8.

[0020] In some embodiments of the present invention, the molar ratio of the poly(3-hexylthiophene) to the catalyst is 1:0.008~0.035.

[0021] In some embodiments of the present invention, the molar ratio of the poly(3-hexylthiophene) to the organophosphorus ligand is 1:0.02~0.06.

[0022] In some embodiments of the present invention, the molar ratio of the poly(3-hexylthiophene) to the inorganic base is 1:1.0~2.0.

[0023] In some embodiments of the present invention, the molar ratio of the poly(3-hexylthiophene) to the organic acid is 1:0.15~0.3.

[0024] In some embodiments of the present invention, in S1, the heating temperature is 80~120°C and the heating time is 18~30 hours.

[0025] In some embodiments of the present invention, in step S2, the phosphorylation specifically includes the following steps:

[0026] The benzyl phosphite-substituted thiophene polymer material, activator, and second solvent are mixed, heated, and then hydrolyzed with hydrochloric acid to obtain the benzyl phosphite-grafted thiophene polymer material.

[0027] In some embodiments of the present invention, the activator includes trimethylbromosilane.

[0028] In some embodiments of the present invention, the molar ratio of the benzyl phosphite-substituted thiophene polymer material to the activator is 1:2 to 4.

[0029] In some embodiments of the present invention, the second solvent is selected from toluene.

[0030] In some embodiments of the present invention, the heating temperature is 30~50°C and the heating time is 18~30 hours.

[0031] In some embodiments of the present invention, the grafting rate of benzylphosphite in the thiophene polymer material grafted with benzylphosphite is 1.0~13.5 mol.

[0032] In some embodiments of the present invention, the grafting rate of benzylphosphite in the thiophene polymer material grafted with benzylphosphite is 1.7~5.8 mol.

[0033] Another object of the present invention is to provide the application of the benzyl phosphorous acid-grafted thiophene polymer material in the preparation of hole transport layers.

[0034] Another object of the present invention is to provide the application of the benzyl phosphorous acid-grafted thiophene polymer material in the fabrication of perovskite solar cells.

[0035] Another objective of this invention is to provide a perovskite solar cell, the perovskite solar cell comprising a hole transport layer, wherein the material forming the hole transport layer is the aforementioned benzylphosphite-grafted thiophene polymer material.

[0036] In some embodiments of the present invention, the perovskite solar cell includes a conductive substrate layer, a hole transport layer, a perovskite active layer, an electron transport layer, a cathode modification layer, and an electrode layer stacked sequentially.

[0037] In some embodiments of the present invention, the material forming the conductive substrate layer is an FTO conductive substrate or an ITO conductive substrate.

[0038] In some embodiments of the present invention, the material forming the perovskite active layer includes lead iodide formamidinium.

[0039] In some embodiments of the present invention, the material forming the electron transport layer includes PCBM.

[0040] In some embodiments of the present invention, the material forming the cathode modification layer includes BCP.

[0041] In some embodiments of the present invention, the material forming the electrode layer includes silver or gold.

[0042] In some embodiments of the present invention, the thickness of the hole transport layer is 10~35nm.

[0043] In some embodiments of the present invention, the thickness of the perovskite active layer is 300~500 nm.

[0044] In some embodiments of the present invention, the thickness of the electron transport layer is 10~60 nm.

[0045] In some embodiments of the present invention, the thickness of the cathode modification layer is 1~10 nm.

[0046] In some embodiments of the present invention, the thickness of the electrode layer is 70~120nm.

[0047] Compared with the prior art, the present invention has the following beneficial effects:

[0048] (1) The perovskite solar cells prepared by the benzyl phosphorous acid-grafted thiophene polymer material provided by the present invention have high battery energy conversion efficiency.

[0049] (2) The perovskite solar cells prepared by the benzyl phosphorous acid-grafted thiophene polymer material provided by the present invention can maintain high cell conversion efficiency and high stability under different humidity environments, and are suitable for regions with different humidity. Attached Figure Description

[0050] The accompanying drawings are provided to further illustrate the present application and form part of the specification. Together with the embodiments of the present application, they serve to explain the present application but do not constitute a limitation thereof. In the drawings:

[0051] Figure 1 The 1H NMR spectrum of the benzyl phosphite-substituted thiophene polymer material prepared in Example 1 is shown.

[0052] Figure 2 The 1H NMR spectrum of the benzyl phosphite-substituted thiophene polymer material prepared in Example 2 is shown.

[0053] Figure 3 The image shows the 1H NMR spectrum of the benzyl phosphite-substituted thiophene polymer material prepared in Example 3.

[0054] Figure 4 The image shows the 1H NMR spectrum of the benzyl phosphorous acid-grafted thiophene polymer material prepared in Example 1.

[0055] Figure 5 The image shows the 1H NMR spectrum of the benzyl phosphorous acid-grafted thiophene polymer material prepared in Example 2.

[0056] Figure 6 The image shows the 1H NMR spectrum of the benzyl phosphorous acid-grafted thiophene polymer material prepared in Example 3. Detailed Implementation

[0057] To enable those skilled in the art to better understand the technical solutions of this invention, the technical solutions of this invention will be clearly and completely described below in conjunction with the embodiments of this invention. Obviously, the described embodiments are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this invention.

[0058] All raw materials used in this invention are commercially available.

[0059] The structure of commercially available poly-3-hexylthiophene used in all embodiments and comparative examples of this invention is as follows:

[0060] .

[0061] Example 1

[0062] This embodiment provides a benzyl phosphorous acid-grafted thiophene polymer material, the preparation method of which includes the following steps:

[0063] S1. Under a nitrogen atmosphere, commercially available poly(3-hexylthiophene a) (1.0 mmol), diethyl 4-bromobenzyl phosphite (0.5 mmol), potassium carbonate (1.0 mmol), palladium chloride (0.01 mmol), triphenylphosphine (0.02 mmol), tervaponic acid (0.15 mmol), and toluene (10 mL) were reacted at 100 °C for 24 h. After the reaction was completed, the mixture was cooled to room temperature, the polymer was precipitated with methanol, and the mixture was washed and dried several times to obtain a thiophene polymer material substituted with diethyl benzyl phosphite.

[0064] S2. Under a nitrogen atmosphere, 0.5 mmol of benzyl phosphite-substituted thiophene polymer, 1.5 mmol of trimethylbromosilane, and 5 mL of toluene were reacted at 40 °C for 24 h. After the reaction was completed, the polymer was precipitated with methanol, washed several times, and then dissolved again in toluene. 6 mL of 3M HCl was slowly added dropwise to the solution. The reaction was stirred at 80 °C for 12 h. After cooling to room temperature, the solution was precipitated in methanol and washed repeatedly with ultrapure water to obtain a benzylphosphite-grafted thiophene polymer material with a yield of 72%, a number-average molecular weight (Mn) of 16.6 kDa, a PDI of 3.1, and a benzylphosphite grafted segment accounting for 1.7% of the benzylphosphite-grafted thiophene polymer material, i.e., a grafting rate of 1.7 mol%. The benzylphosphite-grafted thiophene polymer material comprises a benzylphosphite-grafted thiophene polymer and poly-3-hexylthiophene that did not participate in the grafting reaction. The structure of the benzylphosphite-grafted thiophene polymer is shown below:

[0065] .

[0066] Example 2

[0067] This embodiment provides a benzyl phosphorous acid-grafted thiophene polymer material, the preparation method of which includes the following steps:

[0068] S1. Under a nitrogen atmosphere, commercially available poly(3-hexylthiophene a) (1.0 mmol), diethyl 4-bromobenzyl phosphite (1.0 mmol), potassium carbonate (2.0 mmol), palladium chloride (0.03 mmol), triphenylphosphine (0.06 mmol), tervaponic acid (0.3 mmol), and toluene (10 mL) were reacted at 100 °C for 24 h. After the reaction was completed, the mixture was cooled to room temperature, the polymer was precipitated with methanol, and the mixture was washed and dried several times to obtain a thiophene polymer material substituted with diethyl benzyl phosphite.

[0069] S2. Under a nitrogen atmosphere, 0.5 mmol of benzyl phosphite-substituted thiophene polymer, 2.0 mmol of trimethylbromosilane, and 5 mL of toluene were reacted at 40 °C for 24 h. After the reaction was completed, the polymer was precipitated with methanol and washed several times before being dissolved again in toluene. 7 mL of 3M HCl was slowly added dropwise to the solution. The reaction was stirred at 80 °C for 12 h. After cooling to room temperature, the mixture was precipitated in methanol and washed repeatedly with ultrapure water to obtain a benzylphosphite-grafted thiophene polymer material with a yield of 59%, a number-average molecular weight (Mn) of 17.0 kDa, a PDI of 3.1, and a benzylphosphite grafted segment accounting for 4.4% of the molar percentage of the benzylphosphite-grafted thiophene polymer material, i.e., a grafting rate of 4.4 mol%. The benzylphosphite-grafted thiophene polymer material comprises a benzylphosphite-grafted thiophene polymer and poly-3-hexylthiophene that did not participate in the grafting reaction. The structure of the benzylphosphite-grafted thiophene polymer is shown below:

[0070] .

[0071] Example 3

[0072] This embodiment provides a benzyl phosphorous acid-grafted thiophene polymer material, the preparation method of which includes the following steps:

[0073] S1. Under a nitrogen atmosphere, commercially available poly(3-hexylthiophene a) (1.0 mmol), diethyl 4-bromobenzyl phosphite (1.5 mmol), potassium carbonate (2.0 mmol), palladium chloride (0.03 mmol), triphenylphosphine (0.06 mmol), tervaponic acid (0.3 mmol), and toluene (10 mL) were reacted at 100 °C for 24 h. After the reaction was completed, the mixture was cooled to room temperature, the polymer was precipitated with methanol, and the mixture was washed and dried several times to obtain a thiophene polymer material substituted with diethyl benzyl phosphite.

[0074] S2. Under a nitrogen atmosphere, 0.5 mmol of benzyl phosphite-substituted thiophene polymer, 2.0 mmol of trimethylbromosilane, and 5 mL of toluene were reacted at 40 °C for 24 h. After the reaction was completed, the polymer was precipitated with methanol and washed several times before being dissolved again in toluene. 8 mL of 3M HCl was slowly added dropwise to the solution. The reaction was stirred at 80 °C for 12 h. After cooling to room temperature, the solution was precipitated in methanol and washed repeatedly with ultrapure water to obtain a benzylphosphite-grafted thiophene polymer material with a yield of 65%, a number-average molecular weight (Mn) of 19.1 kDa, a PDI of 3.2, and a benzylphosphite grafted segment accounting for 5.8% of the molar percentage of the benzylphosphite-grafted thiophene polymer material, i.e., a grafting rate of 5.8 mol%. The benzylphosphite-grafted thiophene polymer material comprises a benzylphosphite-grafted thiophene polymer and poly-3-hexylthiophene that did not participate in the grafting reaction. The structure of the benzylphosphite-grafted thiophene polymer is shown below:

[0075] .

[0076] Example 4

[0077] This embodiment provides a benzyl phosphorous acid-grafted thiophene polymer material, the preparation method of which includes the following steps:

[0078] S1. Under a nitrogen atmosphere, commercially available poly(3-hexylthiophene b) (1.0 mmol), diethyl 4-bromobenzyl phosphite (0.3 mmol), potassium carbonate (1.0 mmol), palladium chloride (0.008 mmol), triphenylphosphine (0.02 mmol), tervaponic acid (0.15 mmol), and toluene (10 mL) were reacted at 100 °C for 24 h. After the reaction was completed, the mixture was cooled to room temperature, the polymer was precipitated with methanol, and the mixture was washed and dried several times to obtain a thiophene polymer material substituted with diethyl benzyl phosphite.

[0079] S2. Under a nitrogen atmosphere, 0.5 mmol of a thiophene polymer material substituted with diethyl benzyl phosphite, 1.0 mmol of trimethylbromosilane, and 5 mL of toluene were reacted at 40 °C for 24 h. After the reaction was completed, the polymer was precipitated with methanol and washed several times before being redissolved in toluene. 6 mL of 3M HCl was slowly added dropwise to the solution, and the reaction was stirred at 80 °C for 12 h. After cooling to room temperature, the polymer was precipitated in methanol and washed several times with ultrapure water to obtain a thiophene polymer material grafted with benzyl phosphite, with a yield of 63%, a number-average molecular weight (Mn) of 5.0 kDa, a PDI of 3.0, and a benzyl phosphite grafted segment accounting for 1.0% of the total molar percentage of the benzyl phosphite-grafted thiophene polymer material, i.e., a grafting rate of 1.0%. mol% , wherein the benzyl phosphorous acid-grafted thiophene polymer material comprises a benzyl phosphorous acid-grafted thiophene polymer and poly-3-hexylthiophene without unparticipated grafting reaction, and the structure of the benzyl phosphorous acid-grafted thiophene polymer is shown below:

[0080] .

[0081] Example 5

[0082] This embodiment provides a benzyl phosphorous acid-grafted thiophene polymer material, the preparation method of which includes the following steps:

[0083] S1. Under a nitrogen atmosphere, commercially available poly(3-hexylthiophene C) (1.0 mmol), diethyl 4-bromobenzyl phosphite (3.0 mmol), potassium carbonate (2.0 mmol), palladium chloride (0.035 mmol), triphenylphosphine (0.06 mmol), tervaponic acid (0.3 mmol), and toluene (10 mL) were reacted at 100 °C for 24 h. After the reaction was completed, the mixture was cooled to room temperature, the polymer was precipitated with methanol, and the mixture was washed and dried several times to obtain a thiophene polymer material substituted with diethyl benzyl phosphite.

[0084] S2. Under a nitrogen atmosphere, 0.5 mmol of benzyl phosphite-substituted thiophene polymer, 2.0 mmol of trimethylbromosilane, and 5 mL of toluene were reacted at 40 °C for 24 h. After the reaction was completed, the polymer was precipitated with methanol and washed several times before being dissolved again in toluene. 8 mL of 3M HCl was slowly added dropwise to the solution. The reaction was stirred at 80 °C for 12 h. After cooling to room temperature, the mixture was precipitated in methanol and washed repeatedly with ultrapure water to obtain a benzylphosphite-grafted thiophene polymer material with a yield of 65%, a number-average molecular weight (Mn) of 50.9 kDa, a PDI of 3.5, and a benzylphosphite grafted segment accounting for 13.5% of the molar percentage of the benzylphosphite-grafted thiophene polymer material, i.e., a grafting rate of 13.5 mol%. The benzylphosphite-grafted thiophene polymer material comprises a benzylphosphite-grafted thiophene polymer and poly-3-hexylthiophene that did not participate in the grafting reaction. The structure of the benzylphosphite-grafted thiophene polymer is shown below:

[0085] .

[0086] Example 6

[0087] This embodiment provides a perovskite solar cell, specifically a cell structure of ITO / benzylphosphite-grafted thiophene polymer / FAPbI3 / PCBM / BCP / Ag, and its preparation method includes the following steps:

[0088] (1) Cleaning of transparent substrate: First, take out the ITO transparent conductive glass, peel off the surface plastic protective film, first use dish soap to gently wipe and clean the surface oil stains, then ultrasonically clean it for 15 minutes in a 0.2wt% dish soap aqueous solution, deionized water, and isopropanol, respectively, and finally use nitrogen to blow dry the isopropanol on the ITO surface and pack it in a box for later use.

[0089] (2) Deposition of hole transport layer: The benzyl phosphoric acid-grafted thiophene polymer material prepared in Example 1 was prepared as a 0.2 mg / mL precursor solution with chlorobenzene as solvent. The cleaned ITO was first placed in an ultraviolet ozone cleaner for surface hydrophilic treatment. Then, the precursor solution was pipetted out and evenly covered on the ITO surface. The solvent was removed by spin coating (500 rpm / min, 3 s; 3000 rpm / min, 20 s) to obtain a 20 nm hole transport layer.

[0090] (3) Preparation of perovskite active layer: 280 mg PbI2, 84.1 mg FAI, 5.2 mg MACl and 2.6 mg CsI were dissolved in 600 μL chlorobenzene and stirred at room temperature for 2.5 hours to obtain perovskite precursor solution. The substrate with hole transport layer was transferred to a low-temperature vacuum glove box. The perovskite precursor solution was coated on the hole transport layer by a blade coating method at a speed of 5 mm / s. The substrate was annealed at 100 °C for 60 min to obtain a 400 nm perovskite layer, i.e. perovskite active layer.

[0091] (4) Deposition of electron transport layer: 20 mg of PCBM was dissolved in 1 ml of a mixed solvent of o-dichlorobenzene and chlorobenzene, wherein the volume ratio of o-dichlorobenzene to chlorobenzene was 1:9. After stirring for 24 hours, a 20 mg / ml PCBM solution was formed. The PCBM solution was then coated using a blade coater at a coating speed of 20 mm / s to obtain a 30 nm electron transport layer.

[0092] (5) Deposition of cathode modification layer: Under vacuum, BCP is deposited onto the electron transport layer by thermal evaporation to obtain a 5nm cathode modification layer;

[0093] (6) Deposition of metal electrode layer: A 100 nm thick Ag film was thermally evaporated under high vacuum. The evaporation rate was 0.3 Å / s. 20 nm was deposited at this rate, and then deposited on the surface of the cathode modification layer at 1 Å / s. The deposition thickness was 100 nm.

[0094] Example 7

[0095] This embodiment provides a perovskite solar cell, specifically a cell structure of ITO / benzylphosphite-grafted thiophene polymer / FAPbI3 / PCBM / BCP / Ag, and its preparation method includes the following steps:

[0096] (1) Cleaning of transparent substrate: First, take out the ITO transparent conductive glass, peel off the surface plastic protective film, first use dish soap to gently wipe and clean the surface oil stains, then ultrasonically clean it for 15 minutes in a 0.2wt% dish soap aqueous solution, deionized water, and isopropanol, respectively, and finally use nitrogen to blow dry the isopropanol on the ITO surface and pack it in a box for later use.

[0097] (2) Deposition of hole transport layer: The benzyl phosphoric acid-grafted thiophene polymer material prepared in Example 2 was prepared as a 0.2 mg / mL precursor solution with chlorobenzene as solvent. The cleaned ITO was first placed in an ultraviolet ozone cleaner for surface hydrophilic treatment. Then, the precursor solution was pipetted out and evenly covered on the ITO surface. The solvent was removed by spin coating (500 rpm / min, 3 s; 3000 rpm / min, 20 s) to obtain a 20 nm hole transport layer.

[0098] (3) Preparation of perovskite active layer: 280 mg PbI2, 84.1 mg FAI, 5.2 mg MACl and 2.6 mg CsI were dissolved in 600 μL chlorobenzene and stirred at room temperature for 2.5 hours to obtain perovskite precursor solution. The substrate with hole transport layer was transferred to a low-temperature vacuum glove box. The perovskite precursor solution was coated on the hole transport layer by a blade coating method at a speed of 5 mm / s. The substrate was annealed at 100 °C for 60 min to obtain a 400 nm perovskite layer, i.e. perovskite active layer.

[0099] (4) Deposition of electron transport layer: 20 mg of PCBM was dissolved in 1 ml of a mixed solvent of o-dichlorobenzene and chlorobenzene, wherein the volume ratio of o-dichlorobenzene to chlorobenzene was 1:9. After stirring for 24 hours, a 20 mg / ml PCBM solution was formed. The PCBM solution was then coated using a blade coater at a coating speed of 20 mm / s to obtain a 30 nm electron transport layer.

[0100] (5) Deposition of cathode modification layer: Under vacuum, BCP is deposited onto the electron transport layer by thermal evaporation to obtain a 5nm cathode modification layer;

[0101] (6) Deposition of metal electrode layer: A 100 nm thick Ag film was thermally evaporated under high vacuum. The evaporation rate was 0.3 Å / s. 20 nm was deposited at this rate, and then deposited on the surface of the cathode modification layer at 1 Å / s. The deposition thickness was 100 nm.

[0102] Example 8

[0103] This embodiment provides a perovskite solar cell, specifically a cell structure of ITO / benzylphosphite-grafted thiophene polymer / FAPbI3 / PCBM / BCP / Ag, and its preparation method includes the following steps:

[0104] (1) Cleaning of transparent substrate: First, take out the ITO transparent conductive glass, peel off the surface plastic protective film, first use dish soap to gently wipe and clean the surface oil stains, then ultrasonically clean it for 15 minutes in a 0.2wt% dish soap aqueous solution, deionized water, and isopropanol, respectively, and finally use nitrogen to blow dry the isopropanol on the ITO surface and pack it in a box for later use.

[0105] (2) Deposition of hole transport layer: The benzyl phosphoric acid-grafted thiophene polymer material prepared in Example 3 was prepared as a 0.2 mg / mL precursor solution with chlorobenzene as solvent. The cleaned ITO was first placed in an ultraviolet ozone cleaner for surface hydrophilic treatment. Then, the precursor solution was pipetted out and evenly covered on the ITO surface. The solvent was removed by spin coating (500 rpm / min, 3 s; 3000 rpm / min, 20 s) to obtain a 20 nm hole transport layer.

[0106] (3) Preparation of perovskite active layer: 280 mg PbI2, 84.1 mg FAI, 5.2 mg MACl and 2.6 mg CsI were dissolved in 600 μL chlorobenzene and stirred at room temperature for 2.5 hours to obtain perovskite precursor solution. The substrate with hole transport layer was transferred to a low-temperature vacuum glove box. The perovskite precursor solution was coated on the hole transport layer by a blade coating method at a speed of 5 mm / s. The substrate was annealed at 100 °C for 60 min to obtain a 400 nm perovskite layer, i.e. perovskite active layer.

[0107] (4) Deposition of electron transport layer: 20 mg of PCBM was dissolved in 1 ml of a mixed solvent of o-dichlorobenzene and chlorobenzene, wherein the volume ratio of o-dichlorobenzene to chlorobenzene was 1:9. After stirring for 24 hours, a 20 mg / ml PCBM solution was formed. The PCBM solution was then coated using a blade coater at a coating speed of 20 mm / s to obtain a 30 nm electron transport layer.

[0108] (5) Deposition of cathode modification layer: Under vacuum, BCP is deposited onto the electron transport layer by thermal evaporation to obtain a 5nm cathode modification layer;

[0109] (6) Deposition of metal electrode layer: A 100 nm thick Ag film was thermally evaporated under high vacuum. The evaporation rate was 0.3 Å / s. 20 nm was deposited at this rate, and then deposited on the surface of the cathode modification layer at 1 Å / s. The deposition thickness was 100 nm.

[0110] Example 9

[0111] This embodiment provides a perovskite solar cell, specifically a cell structure of ITO / benzylphosphite-grafted thiophene polymer / FAPbI3 / PCBM / BCP / Ag, and its preparation method includes the following steps:

[0112] (1) Cleaning of transparent substrate: First, take out the ITO transparent conductive glass, peel off the surface plastic protective film, first use dish soap to gently wipe and clean the surface oil stains, then ultrasonically clean it for 15 minutes in a 0.2wt% dish soap aqueous solution, deionized water, and isopropanol, respectively, and finally use nitrogen to blow dry the isopropanol on the ITO surface and pack it in a box for later use.

[0113] (2) Deposition of hole transport layer: The benzyl phosphoric acid-grafted thiophene polymer material prepared in Example 4 was prepared as a 0.2 mg / mL precursor solution with chlorobenzene as solvent. The cleaned ITO was first placed in an ultraviolet ozone cleaner for surface hydrophilic treatment. Then, the precursor solution was pipetted out and evenly covered on the ITO surface. The solvent was removed by spin coating (500 rpm / min, 3 s; 3000 rpm / min, 20 s) to obtain a 20 nm hole transport layer.

[0114] (3) Preparation of perovskite active layer: 280 mg PbI2, 84.1 mg FAI, 5.2 mg MACl and 2.6 mg CsI were dissolved in 600 μL chlorobenzene and stirred at room temperature for 2.5 hours to obtain perovskite precursor solution. The substrate with hole transport layer was transferred to a low-temperature vacuum glove box. The perovskite precursor solution was coated on the hole transport layer by a blade coating method at a speed of 5 mm / s. The substrate was annealed at 100 °C for 60 min to obtain a 400 nm perovskite layer, i.e. perovskite active layer.

[0115] (4) Deposition of electron transport layer: 20 mg of PCBM was dissolved in 1 ml of a mixed solvent of o-dichlorobenzene and chlorobenzene, wherein the volume ratio of o-dichlorobenzene to chlorobenzene was 1:9. After stirring for 24 hours, a 20 mg / ml PCBM solution was formed. The PCBM solution was then coated using a blade coater at a coating speed of 20 mm / s to obtain a 30 nm electron transport layer.

[0116] (5) Deposition of cathode modification layer: Under vacuum, BCP is deposited onto the electron transport layer by thermal evaporation to obtain a 5nm cathode modification layer;

[0117] (6) Deposition of metal electrode layer: A 100 nm thick Ag film was thermally evaporated under high vacuum. The evaporation rate was 0.3 Å / s. 20 nm was deposited at this rate, and then deposited on the surface of the cathode modification layer at 1 Å / s. The deposition thickness was 100 nm.

[0118] Example 10

[0119] This embodiment provides a perovskite solar cell, specifically a cell structure of ITO / benzylphosphite-grafted thiophene polymer / FAPbI3 / PCBM / BCP / Ag, and its preparation method includes the following steps:

[0120] (1) Cleaning of transparent substrate: First, take out the ITO transparent conductive glass, peel off the surface plastic protective film, first use dish soap to gently wipe and clean the surface oil stains, then ultrasonically clean it for 15 minutes in a 0.2wt% dish soap aqueous solution, deionized water, and isopropanol, respectively, and finally use nitrogen to blow dry the isopropanol on the ITO surface and pack it in a box for later use.

[0121] (2) Deposition of hole transport layer: The benzyl phosphorous acid-grafted thiophene polymer material prepared in Example 5 was prepared as a 0.2 mg / mL precursor solution with chlorobenzene as solvent. The cleaned ITO was first placed in an ultraviolet ozone cleaner for surface hydrophilic treatment. Then, the precursor solution was pipetted out and evenly covered on the ITO surface. The solvent was removed by spin coating (500 rpm / min, 3 s; 3000 rpm / min, 20 s) to obtain a 20 nm hole transport layer.

[0122] (3) Preparation of perovskite active layer: 280 mg PbI2, 84.1 mg FAI, 5.2 mg MACl and 2.6 mg CsI were dissolved in 600 μL chlorobenzene and stirred at room temperature for 2.5 hours to obtain perovskite precursor solution. The substrate with hole transport layer was transferred to a low-temperature vacuum glove box. The perovskite precursor solution was coated on the hole transport layer by a blade coating method at a speed of 5 mm / s. The substrate was annealed at 100 °C for 60 min to obtain a 400 nm perovskite layer, i.e. perovskite active layer.

[0123] (4) Deposition of electron transport layer: 20 mg of PCBM was dissolved in 1 ml of a mixed solvent of o-dichlorobenzene and chlorobenzene, wherein the volume ratio of o-dichlorobenzene to chlorobenzene was 1:9. After stirring for 24 hours, a 20 mg / ml PCBM solution was formed. The PCBM solution was then coated using a blade coater at a coating speed of 20 mm / s to obtain a 30 nm electron transport layer.

[0124] (5) Deposition of cathode modification layer: Under vacuum, BCP is deposited onto the electron transport layer by thermal evaporation to obtain a 5nm cathode modification layer;

[0125] (6) Deposition of metal electrode layer: A 100 nm thick Ag film was thermally evaporated under high vacuum. The evaporation rate was 0.3 Å / s. 20 nm was deposited at this rate, and then deposited on the surface of the cathode modification layer at 1 Å / s. The deposition thickness was 100 nm.

[0126] Comparative Example 1

[0127] This comparative example provides a perovskite solar cell, specifically a cell structure of ITO / commercially available poly(3-hexylthiophene) / FAPbI3 / PCBM / BCP / Ag, and its preparation method includes the following steps:

[0128] (1) Cleaning of transparent substrate: First, take out the ITO transparent conductive glass, peel off the surface plastic protective film, first use dish soap to gently wipe and clean the surface oil stains, then ultrasonically clean it for 15 minutes in a 0.2wt% dish soap aqueous solution, deionized water, and isopropanol, respectively, and finally use nitrogen to blow dry the isopropanol on the ITO surface and pack it in a box for later use.

[0129] (2) Deposition of hole transport layer: Commercially available poly(3-hexylthiophene) was prepared as a 0.2 mg / mL precursor solution with chlorobenzene as solvent. The cleaned ITO was first placed in an ultraviolet ozone cleaner for surface hydrophilic treatment. Then, the precursor solution was pipetted out and evenly covered on the ITO surface. The solvent was removed by spin coating (500 rpm / min, 3 s; 3000 rpm / min, 20 s) to obtain a 20 nm hole transport layer.

[0130] (3) Preparation of perovskite active layer: 280 mg PbI2, 84.1 mg FAI, 5.2 mg MACl and 2.6 mg CsI were dissolved in 600 μL chlorobenzene and stirred at room temperature for 2.5 hours to obtain perovskite precursor solution. The substrate with hole transport layer was transferred to a low-temperature vacuum glove box. The perovskite precursor solution was coated on the hole transport layer by a blade coating method at a speed of 5 mm / s. The substrate was annealed at 100 °C for 60 min to obtain a 400 nm perovskite layer, i.e. perovskite active layer.

[0131] (4) Deposition of electron transport layer: 20 mg of PCBM was dissolved in 1 ml of a mixed solvent of o-dichlorobenzene and chlorobenzene, wherein the volume ratio of o-dichlorobenzene to chlorobenzene was 1:9. After stirring for 24 hours, a 20 mg / ml PCBM solution was formed. The PCBM solution was then coated using a blade coater at a coating speed of 20 mm / s to obtain a 30 nm electron transport layer.

[0132] (5) Deposition of cathode modification layer: Under vacuum, BCP is deposited onto the electron transport layer by thermal evaporation to obtain a 5nm cathode modification layer;

[0133] (6) Deposition of metal electrode layer: A 100 nm thick Ag film was thermally evaporated under high vacuum. The evaporation rate was 0.3 Å / s. 20 nm was deposited at this rate, and then deposited on the surface of the cathode modification layer at 1 Å / s. The deposition thickness was 100 nm.

[0134] The performance of the perovskite solar cells of Examples 6-10 and Comparative Example 1 was tested. The test methods are shown below, and the results are shown in Table 1.

[0135] (1) Current-voltage characteristic curve (JV): The JV characteristic curve of the device was measured using a Keithley 2440 light source under simulated AM1.5G spectrum.

[0136] The light intensity was calibrated by NREL using a standard silicon solar cell apparatus and a solar simulator (Newport, 91160). The effective measurement area was 0.07 cm². 2Under both reverse and forward bias scanning, the scanning speed is 100mV / s, and the bias range is -0.2V to 1.2V.

[0137] Table 1. Performance of perovskite solar cells in Examples 6-10 and Comparative Example 1.

[0138]

[0139] As shown in Table 1, the benzyl phosphorous acid-grafted thiophene polymer materials prepared in Examples 6-10 of this invention have high energy conversion efficiency when used to prepare perovskite solar cells.

[0140] Unencapsulated pin-type perovskite solar cells from the same batch of Examples 6-10 and Comparative Example 1 were placed in atmospheric environments with humidity levels of 20%, 40%, and 60%, respectively, and their performance was tested after 30 days. The results are shown in Table 2.

[0141] Table 2. Performance of perovskite solar cells in Examples 6-10 and Comparative Example 1.

[0142]

[0143] As shown in Tables 1-2, the benzyl phosphorous acid-grafted thiophene polymer materials prepared in Examples 6-10 of this invention can maintain high cell conversion efficiency and high stability when used to prepare perovskite solar cells under different humidity environments, making them suitable for regions with varying humidity levels.

[0144] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that after reading this application specification, they can still modify or make equivalent substitutions to the specific implementation of the present invention, but these modifications or changes do not depart from the protection scope of the pending claims of the present invention.

Claims

1. A thiophene polymer grafted with benzyl phosphorous acid, characterized in that, The structural formula of the benzylphosphite-substituted thiophene polymer is shown in formula (Ⅰ): Equation (Ⅰ); Among them, the number-average molecular weight is 5-51 kDa, and the molecular weight distribution index (PDI) is 3.0-3.

5.

2. The benzyl phosphorous acid-grafted thiophene polymer according to claim 1, characterized in that, The number-average molecular weight of the thiophene polymer grafted with benzyl phosphorous acid is 16.6~19.1 kDa, and the molecular weight distribution index (PDI) is 3.1~3.

2.

3. A thiophene polymer material grafted with benzyl phosphorous acid, characterized in that, The preparation method of the thiophene polymer grafted with benzyl phosphorous acid according to any one of claims 1 to 2 includes the following steps: S1. Poly(3-hexylthiophene) reacts with diethyl 4-bromobenzyl phosphite to obtain a thiophene polymer material substituted with diethyl benzyl phosphite; S2. Phosphorylate the thiophene polymer material substituted with diethyl benzyl phosphite to obtain the thiophene polymer material grafted with benzyl phosphite.

4. The benzyl phosphorous acid-substituted thiophene polymer material according to claim 3, characterized in that, The grafting rate of benzylphosphite in the thiophene polymer material grafted with benzylphosphite is 1.0~13.5 mol.

5. The benzyl phosphorous acid-grafted thiophene polymer material according to claim 4, characterized in that, The grafting rate of benzylphosphite in the thiophene polymer material grafted with benzylphosphite is 1.7~5.8 mol.

6. The use of the benzyl phosphorous acid-grafted thiophene polymer material according to any one of claims 3 to 5 in the preparation of hole transport layers and / or perovskite solar cells.

7. A perovskite solar cell, characterized in that, The perovskite solar cell includes a hole transport layer, and the material forming the hole transport layer is the benzyl phosphorous acid-grafted thiophene polymer material as described in any one of claims 3 to 5.

8. The perovskite solar cell according to claim 7, characterized in that, The perovskite solar cell comprises a conductive substrate layer, a hole transport layer, a perovskite active layer, an electron transport layer, a cathode modification layer, and an electrode layer stacked sequentially.

9. The perovskite solar cell according to claim 8, characterized in that, The material forming the conductive substrate layer is an FTO conductive substrate or an ITO conductive substrate; And / or, the material forming the perovskite active layer includes lead iodide formamidinium; And / or, the material forming the electron transport layer includes PCBM; And / or, the material forming the cathode modification layer includes BCP; And / or, the material forming the electrode layer includes silver or gold.

10. The perovskite solar cell according to claim 8, characterized in that, The thickness of the hole transport layer is 10~35nm; And / or, the thickness of the perovskite active layer is 300~500 nm; And / or, the thickness of the electron transport layer is 10~60nm; And / or, the thickness of the cathode modification layer is 1~10 nm; And / or, the thickness of the electrode layer is 70~120nm.

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