A hole transport material based on a carbazole derivative containing a benzene sulfonic acid unit, and a preparation method and use thereof

Abstract

The application discloses a hole transport material based on a carbazole derivative containing a benzene sulfonic acid unit and a preparation method and application thereof, relates to the technical field of solar cells, and a structural formula of the hole transport material is shown as formula I: in the formula, R1 is selected from H, C 1‑6 alkyl, C 1‑6 alkoxy or C1-6 alkylthio; R2 is selected from H, C 1‑6 alkyl, C 1‑6 alkoxy or C1-6 alkylthio. The technical scheme of the application takes 4-bromobenzenesulfonyl chloride as an initial raw material, carries out a substitution reaction with neopentyl alcohol to obtain a corresponding benzene sulfonate, carries out a coupling reaction with carbazole to obtain a carbazole sulfonate, finally carries out a reaction with sodium iodide to obtain an intermediate compound B3, and then carries out a reaction with hydrochloric acid in an ethanol solvent to obtain a final compound. The reaction process is simple, is not dangerous, has a short reaction time, has few side reactions, has a high reaction yield, and has the advantages of high purity of a reaction product and the like.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of solar cells, in particular to a hole transport material based on a carbazole derivative containing a benzene sulfonic acid unit and a preparation method and use thereof. BACKGROUND

[0002] Energy is the driving force of technological development and economic growth, and is the basis for human survival. Since the 21st century, due to the continuous consumption of fossil energy and its non-renewable characteristics, fossil energy will eventually be exhausted. As a renewable clean energy, solar energy is a simple and convenient method to store solar energy as electrical energy. Perovskite solar cells are the most expected solar cells due to their easy preparation, low cost and high efficiency.

[0003] Perovskite solar cells are particularly important in the preparation of perovskite solar cells in the future due to their excellent stability, simple preparation, high efficiency and other characteristics, and the hole transport layer, which is an organic molecule using phosphoric acid as an anchoring group, is an important layer in perovskite solar cells. However, for organic molecules using phosphoric acid groups for anchoring, the stability is reduced due to insufficient anchoring on the transparent conductive oxide (TCO). Therefore, the preparation of new anchoring group organic molecules is very important. SUMMARY

[0004] Therefore, it is necessary to provide a hole transport material based on a carbazole derivative containing a benzene sulfonic acid unit and a preparation method and use thereof in view of the above technical problems.

[0005] In a first aspect, the present application provides a hole transport material based on a carbazole derivative containing a benzene sulfonic acid unit, and the structural formula of the hole transport material is shown as formula I:

[0006] Formula I

[0007] In the formula, R1 is selected from H, C 1-6 alkyl, C 1-6 alkoxy or C1-6 alkylthio;

[0008] R2 is selected from H, C 1-6 alkyl, C 1-6 alkoxy or C1-6 alkylthio.

[0009] Further, R1 is selected from methyl, ethyl, propyl, isopropyl, methoxy, ethoxy, methylthio or ethylthio.

[0010] Further, R2 is selected from methyl, ethyl, propyl, isopropyl, methoxy, ethoxy, methylthio or ethylthio.

[0011] In a second aspect, the present application further provides a preparation method of the hole transport material based on the carbazole derivative containing benzene sulfonic acid unit, which comprises the following steps:

[0012] S1, selecting compound A and neopentyl alcohol to prepare intermediate compound B1 through substitution reaction;

[0013] S2, selecting intermediate compound B1 and carbazole or carbazole derivative to be co-dissolved in toluene to prepare intermediate compound B2 through coupling reaction;

[0014] S3, selecting intermediate compound B2 and sodium iodide to be placed in dry acetone solvent, heating to boiling of the acetone solvent, and preparing intermediate compound B3 through cooling and reflux reaction;

[0015] S4, dissolving intermediate compound B3 in ethanol to prepare the hole transport material.

[0016] Further, the reaction equation for preparing intermediate compound B1 through substitution reaction of compound A and neopentyl alcohol is as follows:

[0017]

[0018] In the formula, represents compound A;

[0019] represents neopentyl alcohol;

[0020] represents intermediate compound B1.

[0021] Further, the reaction equation for preparing intermediate compound B2 through coupling reaction of intermediate compound B1 and carbazole or carbazole derivative co-dissolved in toluene is as follows:

[0022]

[0023] In the formula, represents intermediate compound B1;

[0024] represents intermediate compound B2;

[0025] represents carbazole or carbazole derivative.

[0026] Further, the reaction equation for preparing intermediate compound B3 through cooling and reflux reaction of intermediate compound B2 and sodium iodide placed in dry acetone solvent and heated to boiling of the acetone solvent is as follows:

[0027]

[0028] In the formula, represents intermediate compound B2;

[0029] represents intermediate compound B3.

[0030] Further, the intermediate compound B3 is dissolved in ethanol to prepare the hole transport material, including the following steps:

[0031] S41, the intermediate compound B3 is dissolved in ethanol, and hydrochloric acid is continuously added until no precipitate is generated, to obtain a hydrochloric acid mixed solution;

[0032] S42, the hydrochloric acid mixed solution is subjected to rotary evaporation to prepare the hole transport material containing a sulfonic acid group.

[0033] Further, the intermediate compound B3 is dissolved in ethanol to prepare the hole transport material, and the reaction equation is as follows:

[0034]

[0035] In the formula, represents intermediate compound B3;

[0036] represents the hole transport material.

[0037] In a third aspect, the application further provides a use of the hole transport material based on the carbazole derivative containing a benzene sulfonic acid unit.

[0038] The application has the following beneficial effects:

[0039] 1. The technical scheme of the application takes 4-bromobenzenesulfonyl chloride (compound A) as the initial raw material, and a substitution reaction with neopentyl alcohol obtains the corresponding benzene sulfonate (intermediate compound B1), then a coupling reaction with carbazole obtains the carbazole sulfonate (intermediate compound B2), finally, a reaction with sodium iodide obtains the intermediate compound B3, and then a reaction with hydrochloric acid in an ethanol solvent obtains the final compound (hole transport material), the reaction process is simple, safe, short in reaction time, small in side reaction, high in reaction yield, and high in product purity.

[0040] 2, The application adopts a hot evaporation / rotation coating method to prepare a hole transport layer, which can be mass-produced, and the product itself can be used in perovskite single section, crystalline silicon-perovskite laminated (flat, rough, rough surface), multi-section laminated solar cells; since the product itself has sulfonic acid groups and carbazole, it can be anchored on the ITO (indium tin oxide) surface and interact with the perovskite layer to form a monomolecular hole transport layer, which can improve the hole transport capacity and the open-circuit voltage of the solar cell device; and the product can be used for hot evaporation to prepare the above devices, which can solve the problem of destroying the silicon surface pyramid structure in the crystalline silicon-perovskite laminated layer when the hole transport layer is prepared by a solution method.

[0041] 3, From the molecular structure, it can be divided into three parts, the transmission of carbazole, the π bond of the benzene ring and the anchoring of the sulfonic acid group; the application uses a benzene ring as a connecting part, in general, carbazole is connected with an anchoring group of no more than 4 carbon atoms, and the use of a benzene ring just achieves the connecting effect, while also providing a π bond, which can provide a higher hole movement speed. The use of the sulfonic acid group takes advantage of the strong acidity of the sulfonic acid, which can ensure that it can be anchored on the surface of ITO in large quantities, and the excess unanchored sulfonic acid group can interact with Pb 2+ of the perovskite, which has a better passivation and fixation effect than the phosphoric acid group. BRIEF DESCRIPTION OF DRAWINGS

[0042] The drawings described herein are used to provide further understanding of the application, and form a part of the application. The schematic embodiments of the application and their descriptions are used to explain the application, and do not constitute an improper limitation on the application. In the drawings:

[0043] Figure 1 is a flow chart of a preparation method of a hole transport material based on a carbazole derivative containing a benzene sulfonic acid unit according to an embodiment of the application;

[0044] Figure 2 is a nuclear magnetic resonance spectrum of bromobenzene sulfonic acid neopentyl ester according to an embodiment of the application;

[0045] Figure 3 is a nuclear magnetic resonance spectrum of carbazole benzene sulfonic acid neopentyl ester according to an embodiment of the application;

[0046] Figure 4 is a theoretical JV graph (Target is a SAM layer with (i)) according to an embodiment of the application. DETAILED DESCRIPTION

[0047] In order to make the purpose, technical scheme and advantages of the application clearer, the application will be further described in detail below in combination with the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the application, and do not limit the application.

[0048] The present application provides a hole transport material based on a carbazole derivative containing a benzene sulfonic acid unit, the structural formula of the hole transport material is shown as formula I:

[0049] Formula I

[0050] In the formula, R1 is selected from H, C 1-6 alkyl, C 1-6 alkoxy or C1-6 alkylthio;

[0051] R2 is selected from H, C 1-6 alkyl, C 1-6 alkoxy or C1-6 alkylthio.

[0052] In the description of the present application, R1 is selected from methyl, ethyl, propyl, isopropyl, methoxy, ethoxy, methylthio or ethylthio.

[0053] In the description of the present application, R2 is selected from methyl, ethyl, propyl, isopropyl, methoxy, ethoxy, methylthio or ethylthio.

[0054] Please refer to Figure 1 The present application also provides a preparation method of the hole transport material based on the carbazole derivative containing the benzene sulfonic acid unit, the preparation method comprises the following steps:

[0055] S1, selecting compound A and neopentyl alcohol, and preparing intermediate compound B1 through substitution reaction.

[0056] In the description of the present application, the reaction equation for preparing intermediate compound B1 through substitution reaction by selecting compound A and neopentyl alcohol is as follows:

[0057]

[0058] In the formula, compound A is represented;

[0059] neopentyl alcohol is represented;

[0060] intermediate compound B1 is represented.

[0061] S2, selecting intermediate compound B1, and co-dissolving carbazole or carbazole derivative in toluene, and preparing intermediate compound B2 through coupling reaction.

[0062] In the description of the present application, the reaction equation for preparing intermediate compound B2 through coupling reaction by co-dissolving intermediate compound B1 and carbazole or carbazole derivative in toluene is as follows:

[0063]

[0064] In the formula, represents intermediate compound B1;

[0065] represents intermediate compound B2;

[0066] represents carbazole or a carbazole derivative.

[0067] S3, intermediate compound B2 and sodium iodide are placed in dry acetone solvent, heated to boiling acetone solvent, and after cooling reflux reaction, intermediate compound B3 is prepared.

[0068] In the description of the present application, the reaction equation for preparing intermediate compound B3 by placing intermediate compound B2 and sodium iodide in dry acetone solvent, heating to boiling acetone solvent, and after cooling reflux reaction is as follows:

[0069]

[0070] In the formula, represents intermediate compound B2;

[0071] represents intermediate compound B3.

[0072] S4, intermediate compound B3 is dissolved in ethanol to prepare a hole transport material.

[0073] In the description of the present application, dissolving intermediate compound B3 in ethanol to prepare a hole transport material includes the following steps:

[0074] S41, intermediate compound B3 is dissolved in ethanol, and hydrochloric acid is continuously added until no precipitate is formed to obtain a hydrochloric acid mixed solution;

[0075] S42, the hydrochloric acid mixed solution is rotary evaporated to prepare a hole transport material containing a sulfonic acid group.

[0076] In the description of the present application, the reaction equation for preparing a hole transport material by dissolving intermediate compound B3 in ethanol is as follows:

[0077]

[0078] In the formula, represents intermediate compound B3;

[0079] represents a hole transport material.

[0080] In addition, the application further provides a use of a hole transport material based on a carbazole derivative containing a benzene sulfonic acid unit, and the use of the hole transport material in a perovskite solar cell.

[0081] Embodiment

[0082] The specific preparation process is as follows:

[0083] (1) In a 100ml round-bottom flask, compound A (2.52g, 10mmol) and neopentanol (0.9g, 1.2mmol) were added, and dichloromethane (15ml) was added under the condition of ice water bath, and pyridine (1.21ml, 15mmol) was gradually added, and stirring was continuously carried out for 12h. Ethyl ether (50ml) was added to the flask after the reaction was completed, and the organic solvent was removed by rotary evaporation under reduced pressure to obtain a light yellow solid, intermediate compound B1 (2.4g, 70%), and the reaction equation is as follows:

[0084]

[0085] (2) In a round-bottom flask, intermediate compound B1 (0.9g, 3mmol), pyridine (0.54g, 3.2mmol), sodium tert-butoxide (0.72g, 7.5mmol), Pd catalyst (135mg, 0.15mmol), phosphorus fluoroborate (277mg, 0.128mmol), toluene (30ml) were added in sequence, under the protection of nitrogen, the oil bath was heated to 100℃, and the reaction was refluxed for 36h. Petroleum ether was added for extraction, and the organic phase was collected and dried with anhydrous sodium sulfate. After the organic solvent was removed by rotary evaporation under reduced pressure, column chromatography separation (petroleum ether: ethyl acetate = 10:1) was carried out, and intermediate compound B2 (200mg, 20%) in white solid was obtained, and the reaction equation is as follows:

[0086]

[0087] (3) In a round-bottom flask, intermediate compound B2 (0.6g, 1.5mmol), sodium iodide (2.5g, 16mmol), and acetone (15ml) were added in sequence, under the condition of nitrogen, the oil bath was heated to 100℃, and the reaction was refluxed for 12h. White solid intermediate compound B3 was obtained, and the reaction equation is as follows:

[0088]

[0089] (4) The solid obtained in step (3) was placed in a round-bottom flask, hydrochloric acid (1ml, 47%) and ethanol (10ml) were added, stirring was carried out for 4h, the organic phase was taken, and rotary evaporation was carried out to obtain the final product hole transport material, and the reaction equation is as follows:

[0090]

[0091] In addition, such as Figure 2 As shown, it can be seen that 1.0 corresponds to the value on neopentyl bromobenzenesulfonate. 9 The H peak at 3.5-4.0 corresponds to the CH2 peak connected to oxygen on the ester, while the 1:1 peak at 7.5-8.0 corresponds to the H on the benzene ring. This indicates that the compound corresponding to this NMR is neopentyl bromobenzenesulfonate.

[0092] Depend on Figure 3 It can be seen that 1.0 corresponds to the value on neopentyl carbazole benzyl sulfonate. 9 The H peak at 3.5-4.0 corresponds to the CH2 peak connected to oxygen on the ester, while the 1:2 peak at 7.25-7.5 corresponds to the H on the benzene ring of benzenesulfonic acid and the benzene ring of carbazole. The 1:2 peak at 7.75-8.25 also corresponds to the H on the benzene ring of sulfonic acid and the benzene ring of carbazole. Moreover, the H on the benzene ring of benzenesulfonic acid and the benzene ring of carbazole are symmetrical. Therefore, it can be seen that the compound corresponding to this NMR is neopentyl carbazole benzenesulfonic acid ester.

[0093] Depend on Figure 4 As can be seen from the JV, after using carbazole benzenesulfonic acid as the SAM layer, the Voc (open-circuit voltage) and Jsc (short-circuit current) of the perovskite device are both improved, so the use of carbazole benzenesulfonic acid can improve the efficiency of the device.

[0094] In summary, by utilizing the above-mentioned technical solution of the present invention, the following steps are taken: using 4-bromobenzenesulfonyl chloride (compound A) as the initial raw material, a substitution reaction is carried out with neopentyl alcohol to obtain the corresponding benzenesulfonate ester (intermediate compound B1), followed by a coupling reaction with carbazole to obtain carbazole sulfonate ester (intermediate compound B2), and finally reacting with sodium iodide to obtain intermediate compound B3. This intermediate compound B3 is then reacted with hydrochloric acid in an ethanol solvent to obtain the final compound (hole transport material). The reaction process is simple, safe, has a short reaction time, few side reactions, high reaction yield, and high product purity.

[0095] This invention employs a thermal evaporation / spin-coating method to prepare the hole transport layer, enabling mass production. The product itself can be used in perovskite single-segment, crystalline silicon-perovskite tandem (planar, textured, rough surface), and multi-segment tandem solar cells. Because the product contains sulfonic acid groups and carbazole, it can anchor onto the ITO (indium tin oxide) surface and interact with the perovskite layer to form a monomolecular hole transport layer. This monomolecular hole transport layer can improve hole transport capability and increase the open-circuit voltage of the solar cell device. Furthermore, the product can be used for thermal evaporation to prepare the above devices, solving the problem of damaging the textured pyramid structure of the silicon surface in the crystalline silicon-perovskite tandem when preparing the hole transport layer using solution methods.

[0096] From the molecular structure, it can be divided into three parts, the transmission of carbazole, the π bond of benzene ring and the anchoring of sulfonic acid group; the application uses benzene ring as the connecting part, in general, no more than 4 carbon atoms are connected between carbazole and the anchoring group, and the use of benzene ring just achieves the connecting effect, and also provides the π bond, which can provide a higher hole moving speed. The use of the sulfonic acid group is to utilize the strong acidity of the sulfonic acid, which can ensure that it can be anchored on the surface of ITO in a large amount, and the excess unanchored sulfonic acid group can interact with Pb 2+ of the perovskite, compared with the phosphoric acid group, has a better passivation and fixation effect.

[0097] It should be understood that, although each step in the flowchart of the accompanying drawings is shown in sequence according to the direction of the arrow, these steps are not necessarily executed in sequence according to the direction of the arrow. Unless explicitly stated herein, the execution of these steps is not strictly limited in sequence, and they can be executed in other sequences. Moreover, at least part of the steps in the flowchart of the accompanying drawings can include multiple sub-steps or multiple stages, which are not necessarily executed at the same time, but can be executed at different times, and the execution sequence is not necessarily sequential, but can be executed in rotation or alternation with at least part of other steps or sub-steps or stages of other steps.

Claims

1. A hole-transport material based on a carbazole derivative containing a benzene sulfonic acid unit, characterized by The structural formula of the hole transport material is shown as Formula I: Formula I wherein R1is selected from H, C 1-6 alkyl, C 1-6 alkoxy or C1-6alkylthio; R2is selected from H, C 1-6 alkyl, C 1-6 alkoxy or Ci-6alkylthio.

2. The hole transport material based on a carbazole derivative containing a benzene sulfonic acid unit according to claim 1, characterized in that, The R1 is selected from methyl, ethyl, propyl, isopropyl, methoxy, ethoxy, methylthio or ethylthio.

3. The hole transport material based on a carbazole derivative containing a benzene sulfonic acid unit according to claim 1, characterized in that, The R2 is selected from methyl, ethyl, propyl, isopropyl, methoxy, ethoxy, methylthio or ethylthio.

4. A method for producing a hole-transport material based on a carbazole derivative containing a benzenesulfonic acid unit for achieving the production of the hole-transport material based on the carbazole derivative containing a benzenesulfonic acid unit according to any one of claims 1 to 3, characterized by, The preparation method comprises the following steps: S1, selecting compound A and neopentyl alcohol, and preparing intermediate compound B1 through substitution reaction; S2, selecting the intermediate compound B1, and co-dissolving in toluene with carbazole or carbazole derivative, and preparing intermediate compound B2 through coupling reaction; S3, selecting the intermediate compound B2 and sodium iodide, and placing in dry acetone solvent, heating to boiling of the acetone solvent, and preparing intermediate compound B3 through cooling and reflux reaction; S4, dissolving the intermediate compound B3 in ethanol to prepare the hole transport material; The reaction equation of selecting compound A and neopentyl alcohol, and preparing intermediate compound B1 through substitution reaction is as follows: ； wherein represents compound A; represents neopentyl alcohol; This refers to intermediate compound B1; The reaction equation of selecting the intermediate compound B1, and co-dissolving in toluene with carbazole or carbazole derivative, and preparing intermediate compound B2 through coupling reaction is as follows: ； in which represents the intermediate compound B1; This refers to intermediate compound B2; represents carbazole or a carbazole derivative; The reaction equation of selecting the intermediate compound B2 and sodium iodide, and placing in dry acetone solvent, heating to boiling of the acetone solvent, and preparing intermediate compound B3 through cooling and reflux reaction is as follows: ； in which represents the intermediate compound B2; This refers to intermediate compound B3; The reaction equation of selecting the intermediate compound B3 in ethanol to prepare the hole transport material comprises the following steps: S41, dissolving the intermediate compound B3 in ethanol, and continuously adding hydrochloric acid until no precipitate is generated, to obtain a hydrochloric acid mixed solution; S42, performing rotary evaporation on the hydrochloric acid mixed solution to prepare the hole transport material containing sulfonic acid group.

5. The method for preparing a hole transport material based on a carbazole derivative containing a benzenesulfonic acid unit according to claim 4, characterized in that, The reaction equation of selecting the intermediate compound B3 in ethanol to prepare the hole transport material is as follows: ； in which represents the intermediate compound B3; represents a hole-transport material.

6. Use of a hole-transport material based on a carbazole derivative containing a benzenesulfonic acid unit for the implementation of the use of a hole-transport material based on a carbazole derivative containing a benzenesulfonic acid unit according to any of claims 1 to 3, characterized in that The hole transport material is applied to the use of perovskite solar cell.

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