Halo compounds, preparation method and application thereof, and solar cell

Abstract

The application relates to the technical field of organic functional materials, in particular to a heiro compound, a preparation method and application thereof, and a solar cell. The molecular structure of the heiro compound is shown in a general formula I: wherein R1 and R2 are independently selected from any one of a hydrogen atom, C1-C 24 alkyl, C1-C 24 alkoxy, C2-C 24 alkoxyalkyl, C2-C 24 alkylthioalkyl, a phenyl, a phenoxy, a substituted phenyl, and a substituted phenoxy; L1 is selected from a hydrogen atom or a hydroxyl group, and L2 is selected from a hydrogen atom or a hydroxyl group. The heiro compound provided by the application not only has the characteristics of light and heat stability, but also has good hole transport performance, and can be used as a hole transport material in a solar cell, so that the solar cell has good photoelectric conversion efficiency.

Description

Technical Field

[0001] This application belongs to the field of organic functional materials technology, and particularly relates to a horny compound, its preparation method and application, and solar cells. Background Technology

[0002] With the environmental pollution caused by fossil fuels and their increasing depletion, both domestic and international efforts are actively developing clean and renewable alternative energy sources, such as solar, hydro, and wind power. Solar cells are batteries that utilize the photovoltaic effect to generate current and voltage. They absorb sunlight to produce electrons and holes, which in turn generate current in a closed circuit. Because solar cells directly convert solar energy into electrical energy, and sunlight is readily available, clean, pollution-free, and low-cost, this technology is gaining increasing attention.

[0003] Currently, NP-type solar cells based on monocrystalline silicon (Si) have photovoltaic conversion efficiencies exceeding 20% ​​and are already being used in solar power generation. Furthermore, solar cells based on gallium arsenide (GaAs) semiconductors have conversion efficiencies even higher than those based on monocrystalline silicon (Si) NP-type solar cells. However, these inorganic semiconductor-based solar cells require extremely high-purity materials to achieve high efficiency. Purifying raw materials consumes a significant amount of energy, and the processes of manufacturing raw material crystals and thinning the crystals require expensive processing equipment. This makes reducing the manufacturing cost of solar cells very difficult, thus hindering their large-scale application.

[0004] To reduce the manufacturing cost of solar cells, it is necessary to significantly reduce the cost of core materials and simplify the manufacturing process. Among various solar cells that may replace inorganic semiconductors, perovskite solar cells (PSCs) are currently receiving the most attention. Organic-inorganic lead halide perovskite solar cells hold great promise as replacements for inorganic solar cells because their power conversion efficiency (PCE) has increased from 3.8% in the past few years to 25.7% currently. This development is far faster than that of organic photovoltaics (OPV), dye-sensitized solar cells (DSSCs), and other photovoltaic cells because PSCs, in addition to their high efficiency, are easier to manufacture and have lower costs.

[0005] Hole transport layers and electron transport layers play a crucial role in improving the performance of PSC devices. Hole transport materials (HTMs) not only extract and collect photogenerated holes from the perovskite active layer but also act as electron blocking layers to prevent charge recombination. 2,2',7,7'-tetratetra[N,N-di(4-methoxyphenyl)amino]-9,9'-spirodifluorene (Spiro-OMeTAD) and poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) are currently the most widely used hole transport materials for n–i–p type PSCs. However, both materials are unstable in terms of thermal, optical, and chemical properties, and have low mobility and high cost. For example, Spiro-OMeTAD has low conductivity and requires lithium salt doping, which significantly reduces the stability of PSC devices. In addition, the synthesis route of Spiro-OMeTAD involves many steps, the purification process is complex, and the device reproducibility is poor. Summary of the Invention

[0006] The purpose of this application is to provide a horn-like compound, its preparation method and application, and a solar cell, aiming to solve the technical problem of how to provide more hole transport materials.

[0007] To achieve the above-mentioned objectives, the technical solution adopted in this application is as follows:

[0008] In a first aspect, this application provides a horny compound, the general molecular structure of which is shown in Formula I:

[0009]

[0010] Among them, R1 and R2 are independently selected from hydrogen atoms and C1-C atoms, respectively. 24 Alkyl, C1-C 24 Alkoxy, C2-C 24 Alkoxyalkyl, C2-C 24 Any one of alkylthioalkyl, phenyl, phenoxy, substituted phenyl, or substituted phenoxy; L1 is selected from hydrogen atom or hydroxyl group, and L2 is selected from hydrogen atom or hydroxyl group.

[0011] Secondly, this application provides a method for preparing anorexic compounds, comprising the following steps:

[0012] 4-R1-5-R2-phthalonitrile and lithium metal were mixed and subjected to a first reaction to obtain the intermediate shown in Formula II;

[0013] The intermediate shown in Formula II was mixed with phosphorus tribromide to carry out a second reaction, yielding the oxalis compound shown in Formula I.

[0014]

[0015] Thirdly, this application provides the application of the above-mentioned horn-like compounds and / or horn-like compounds prepared by the above-mentioned preparation method as hole transport materials.

[0016] Fourthly, this application provides a solar cell, including a positive electrode and a negative electrode disposed opposite to each other, and a semiconductor layer located between the positive electrode and the negative electrode. A hole transport layer is disposed between the semiconductor layer and the positive electrode. The material of the hole transport layer is the arsenic compound of this application and / or the arsenic compound prepared by the preparation method of this application.

[0017] The horn-like compounds provided in the first aspect of this application have a unique core chemical structure. Through the substitution of various groups R1 and R2, a variety of horn-like compounds can be formed. The molecular structure of the horn-like compounds shown in this application not only possesses optical and thermal stability but also exhibits excellent hole transport performance. Therefore, the horn-like compounds of this application can be used as hole transport materials in solar cells, enabling the solar cells to have excellent photoelectric conversion efficiency, thus showing great application prospects.

[0018] The second aspect of this application provides a method for preparing horn-like compounds, which involves first reacting 4-R1-5-R2-phthalonitrile with lithium metal to obtain an intermediate as shown in Formula II, and then reacting the intermediate with phosphorus tribromide to obtain a horn-like compound as shown in Formula I. This preparation method is simple, and the obtained horn-like compounds not only have optical and thermal stability, but also have excellent hole transport performance, showing broad application prospects.

[0019] The application provided in the third aspect of this application is based on the fact that the molecular structure of the horn-like compounds shown in I not only has the characteristics of optical and thermal stability, but also has excellent hole transport performance. Therefore, such unique horn-like compounds and / or horn-like compounds prepared by the corresponding preparation methods can be used as hole transport materials.

[0020] The solar cell provided in the fourth aspect of this application has a hole transport layer made of a unique horny compound and / or a horny compound prepared by the preparation method of this application. Therefore, the solar cell of this application has a very good photoelectric conversion efficiency. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1This is the electrospray mass spectra of compound POTBC(Eu)4 in Example 1 of this application;

[0023] Figure 2 For compound POTBC(Eu)4 in Example 1 of this application 1 Spectra obtained by H nuclear magnetic resonance spectroscopy;

[0024] Figure 3 For compound POTBC(Eu)4 in Example 1 of this application 31 Spectrum obtained by P nuclear magnetic resonance spectroscopy;

[0025] Figure 4 The UV-Vis absorption spectrum of compound POTBC(Eu)4 in Example 1 of this application;

[0026] Figure 5 This is a SEM image of the perovskite solar cell provided in Embodiment 2 of this application;

[0027] Figure 6 The JV curve is for the perovskite solar cell provided in Example 2 of this application. Detailed Implementation

[0028] To make the technical problems, technical solutions, and beneficial effects of this application clearer, the following detailed description is provided in conjunction with embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0029] In this application, the term "and / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0030] In this application, "at least one" means one or more, and "more than one" means two or more. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of a single item or a plurality of items.

[0031] It should be understood that in the various embodiments of this application, the order of the above processes does not imply the order of execution. Some or all steps may be executed in parallel or sequentially. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0032] The terminology used in the embodiments of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of this application. The singular forms “a,” “the,” and “the” used in the embodiments of this application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise.

[0033] The weights of the relevant components mentioned in the embodiments of this application can refer not only to the specific content of each component, but also to the proportional relationship between the weights of the components. Therefore, any scaling up or down of the content of the relevant components according to the embodiments of this application is within the scope disclosed in the embodiments of this application. Specifically, the mass described in the embodiments of this application can be a mass unit known in the chemical industry, such as μg, mg, g, or kg.

[0034] The terms "first" and "second" are used for descriptive purposes only, to distinguish objects, such as substances, from one another, and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. For example, without departing from the scope of the embodiments of this application, "first XX" may also be referred to as "second XX," and similarly, "second XX" may also be referred to as "first XX." Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of that feature.

[0035] The first aspect of this application provides a horny compound, the general molecular structure of which is shown in Formula I:

[0036]

[0037] Among them, R1 and R2 are independently selected from hydrogen atoms and C1-C atoms, respectively. 24 Alkyl, C1-C 24 Alkoxy, C2-C 24 Alkoxyalkyl, C2-C 24 Any one of alkylthioalkyl, phenyl, phenoxy, substituted phenyl, or substituted phenoxy; L1 is selected from hydrogen atom or hydroxyl group, and L2 is selected from hydrogen atom or hydroxyl group.

[0038] The horn-like compounds provided in this application have a unique core chemical structure. Through the substitution of various groups in R1 and R2, a variety of horn-like compounds can be formed. The molecular structure of the horn-like compounds shown in this application not only possesses optical and thermal stability but also exhibits excellent hole transport performance. Therefore, the horn-like compounds of this application can be used as hole transport materials in solar cells, enabling the solar cells to have excellent photoelectric conversion efficiency, thus showing great application prospects.

[0039] In one embodiment, C1-C 24Alkyl groups (i.e., those with 1 to 24 carbon atoms) can be C1-C2. 20 Alkyl, C1-C 12 Alkyl, C1-C 10 Alkyl, C1-C3 alkyl, etc. In some embodiments, it may be methyl, ethyl, propyl, butyl, isobutyl, pentyl, isopentyl, etc.

[0040] In one embodiment, C1-C 24 Alkoxy groups (i.e., those with 1 to 24 carbon atoms) can be C1-C. 20 Alkoxy, C1-C 12 Alkoxy, C1-C 10 Alkoxy, C1-C3 alkoxy, etc. In some embodiments, it may be methoxy, ethoxy, propoxy, butoxy, pentoxy, etc.

[0041] In one embodiment, C2-C 24 Alkoxyalkyl groups (i.e., those with 2 to 24 carbon atoms) can be C2-C. 20 Alkoxyalkyl, C2-C 12 Alkoxyalkyl, C2-C 10 Alkoxyalkyl, C1-C3 alkoxyalkyl, etc. In some embodiments, it may be methyloxyethyl, ethyloxybutyl, propyloxybutyl, etc.

[0042] In one embodiment, C2-C 24 Alkyl thioalkyl groups (i.e., those with 2 to 24 carbon atoms) can be C2-C 20 Alkyl thioalkyl, C2-C 12 Alkyl thioalkyl, C2-C 10 Alkylthioalkyl, C1-C3 alkylthioalkyl, etc. In some embodiments, it may be methylthioethyl, ethylthiobutyl, propylthiobutyl, etc.

[0043] In one embodiment, the substituents in the substituted phenyl group are selected from halogen atoms, C1-C... 10 Alkyl, C1-C 10 Alkoxy, C3-C 10 cycloalkyl, C2-C 10 At least one of the alkenyl groups. The substituents in the substituted phenoxy group are selected from halogen atoms, C1-C... 10 Alkyl, C1-C 10 Alkoxy, C3-C 10 cycloalkyl, C2-C 10 At least one of the alkenyl groups. The halogen atom can be fluorine, chlorine, bromine, iodine, etc.

[0044] In one embodiment, R1 and R2 may be the same or different. Specifically, at least one of R1 and R2 may be selected as phenyl, phenoxy, substituted phenyl, or substituted phenoxy. Due to the presence of the benzene ring, the hole transport performance of the phenoxy compound shown in I can be further improved.

[0045] In one specific embodiment, R1 is selected from 4-allyl-2-methoxyphenoxy, R2 is selected from hydrogen atoms, and the corresponding arsenic compound is represented by POTBC(Eu)4.

[0046] In one specific embodiment, R1 is selected from butoxy, R2 is selected from butoxy, and the corresponding anthraquinone compound is represented by POTBC(β-OBu)4; or, R1 is selected from butyl, R2 is selected from butyl, and the corresponding anthraquinone compound is represented by POTBC(β-Bu)4.

[0047] The second aspect of this application provides a method for preparing anorexic compounds, comprising the following steps:

[0048] S01: 4-R1-5-R2-phthalonitrile and lithium metal are mixed and subjected to a first reaction to obtain the intermediate shown in Formula II;

[0049] S02: Mix the intermediate shown in Formula II with phosphorus tribromide to carry out a second reaction to obtain the oxalis compound shown in Formula I;

[0050]

[0051] The method for preparing horn-like compounds provided in this application involves first reacting 4-R1-5-R2-phthalonitrile with lithium metal to obtain an intermediate as shown in Formula II, and then reacting the intermediate with phosphorus tribromide to obtain a horn-like compound as shown in Formula I. This preparation method is simple, and the obtained horn-like compounds not only have optical and thermal stability, but also have excellent hole transport performance, showing broad application prospects.

[0052] In step S01: 4-R1-5-R2-phthalonitrile reacts with lithium metal to produce the intermediate shown in formula II.

[0053] In one embodiment, the first reaction is carried out in an alkanolic solvent, such as an alkanolic solvent with 5 to 15 carbon atoms. 4-R1-5-R2-phthalonitrile and lithium metal are dissolved in the alkanolic solvent, and then the first reaction is carried out by heating. Specifically, the temperature of the first reaction is 120–160°C, and the time is 3–5 hours, under which the reaction proceeds well. Further, the molar ratio of 4-R1-5-R2-phthalonitrile to lithium metal is 1:4–6, under which the reaction is more complete.

[0054] In step S02: the intermediate shown in II reacts with phosphorus tribromide to obtain the target compound shown in formula I.

[0055] In one embodiment, the second reaction is carried out in a pyridine solvent. The intermediate shown in II is dissolved in pyridine, and PBr3 is dissolved in pyridine, then the two are mixed and heated to carry out the second reaction. Specifically, the temperature of the second reaction is 90–100 °C, and the time is 0.5–1.5 h, under which the reaction proceeds well. Further, the molar ratio of the intermediate shown in II to phosphorus tribromide is 1:32–38, under which the reaction is more complete.

[0056] Taking an example where the first reaction is carried out in n-pentanol solvent and the second reaction in pyridine solvent, the specific reaction formulas are shown below:

[0057]

[0058] The specific preparation steps are as follows:

[0059] S1: Preparation of phthalocyanine compound H2Pc(R1R2)4 (i.e., the intermediate shown in Formula II):

[0060] Add 5 mL of n-pentanol to a 50 mL three-necked flask and bubble with N2 gas for 10 minutes with stirring; add lithium metal (40 mg, 5 mmol) and raise the temperature to 90 °C; add 1 mmol of 4-R1-5-R2-phthalonitrile and react at 140 °C for 4 hours to obtain a dark blue product; after cooling, add a mixture of methanol / concentrated hydrochloric acid (5 mL 1:1 v / v), precipitate, cool, filter, wash with water and dry; purify the dried product by column chromatography (400 mesh silica, CH2Cl2 as eluent).

[0061] S2: Preparation of POTBC(R1R2)4 (i.e., the oxalis compound shown in Formula I):

[0062] Phthalocyanine precursor H₂Pc(R₁R₂)₄ (1.0 mmol) was added to a 50 mL three-necked round-bottom flask containing pyridine (10 mL), which was equipped with a reflux condenser and an argon inlet. After purging with argon for 10 minutes, pyridine (5 mL) containing PBr₃ (3.2 mL, 35 mmol) was added, and the mixture was heated at 95 °C with stirring under an argon atmosphere for 1 h. After cooling, the mixture was poured into water and filtered, and the solid was thoroughly washed with water. The dried crude product was dissolved in dichloromethane (DCM) and purified by column chromatography on silica gel using DCM / chloroform as the eluent.

[0063] The third aspect of this application also provides an application in which the molecular structure of the horn-like compound shown in Formula I of this application not only has the characteristics of optical and thermal stability, but also has excellent hole transport performance. Therefore, such unique horn-like compounds and / or horn-like compounds prepared by the above preparation method can be used as hole transport materials.

[0064] Specifically, the horn-like compounds shown in Formula I are easy to synthesize and purify, and can be used as materials for undoped hole transport layers in perovskite solar cells. The horn-like compounds shown in Formula I can replace the existing undoped lithium salt SpiroOMeTAD hole transport layer when used as undoped hole transport layers, and the resulting perovskite solar cells have excellent photoelectric conversion efficiency.

[0065] A fourth aspect of this application also provides a solar cell, including a positive electrode and a negative electrode disposed opposite to each other, and a semiconductor layer located between the positive electrode and the negative electrode. A hole transport layer is disposed between the semiconductor layer and the positive electrode. The material of the hole transport layer is a horny compound of this application and / or a horny compound prepared by the preparation method of this application.

[0066] The solar cell provided in this application embodiment has a hole transport layer made of a unique horny compound and / or a horny compound prepared by the preparation method of this application. Therefore, the solar cell in this application embodiment has a very good photoelectric conversion efficiency.

[0067] Specifically, the solar cell in this application embodiment is a perovskite solar cell, that is, the semiconductor layer therein is a perovskite light-absorbing layer, which can be an organic-inorganic lead halide perovskite layer, including a transparent conductive substrate (as the negative electrode), an electron transport layer, a perovskite light-absorbing layer, a hole transport layer and a metal electrode layer (as the positive electrode) arranged sequentially; the material of the hole transport layer is a horn-based compound as shown in Formula I, and the hole transport layer has good water and thermal stability and high hole mobility.

[0068] Specifically, the transparent conductive substrate is preferably a conductive glass substrate (FTO), and the thickness of the transparent conductive substrate is preferably 360–450 nm. The electron transport layer is a titanium dioxide thin film, and the thickness of the electron transport layer is preferably 40–70 nm. The perovskite light-absorbing layer is a perovskite thin film, and the thickness of the perovskite light-absorbing layer is preferably 350–460 nm. The material of the perovskite light-absorbing layer is Cs. x FA y MA zPbI3 hybrid perovskite solar cells (x = 0.01–0.09, y = 0.50–0.90, x+y+z = 1). The hole transport layer has a thickness of 60–130 nm. The metal electrode layer is preferably a gold or silver layer, with a preferred thickness of 30–70 nm. The gold or silver electrode is also composited onto a portion of the surface of the transparent conductive substrate.

[0069] The above-mentioned method for preparing perovskite solar cells includes the following steps: depositing an electron transport layer, depositing a perovskite light absorption layer, spin-coating a hole transport layer, depositing a metal electrode layer, and heat-treating the substrate in sequence to obtain a perovskite solar cell.

[0070] The transparent conductive substrate is sequentially ultrasonically cleaned with water-glass cleaner, anhydrous ethanol, acetone, isopropanol, and anhydrous ethanol, followed by oxygen plasma cleaning to obtain a clean transparent conductive substrate. Ultrasonic cleaning with each cleaning agent lasts for 35–45 minutes, more preferably 40 minutes.

[0071] The electron transport layer is deposited using a spin-coating solution prepared from an electron transport material. The electron transport material solution can be a TiO2 precursor solution, obtained by reacting a mixture of ethanol, tetraisopropyl titanate, and concentrated hydrochloric acid. The TiO2 precursor solution is then spin-coated onto a transparent conductive substrate and calcined to obtain a transparent conductive substrate-electron transport layer composite layer. The spin-coating speed is 1900–2100 rpm, preferably 2000 rpm; the spin-coating time is 35–45 s, preferably 40 s. The calcination temperature is 530–570 °C, preferably 550 °C, and the calcination time is 55–65 min, preferably 60 min.

[0072] The perovskite light-absorbing layer was prepared by spin-coating perovskite material, preferably a mixture of Cs. x FA y MA z PbI3.

[0073] The spin-coated hole transport layer is prepared using a solution of a chlorobenzene compound as shown in Formula I, wherein the solvent is selected from one or more of chlorobenzene, toluene, and dimethyl sulfoxide, more preferably chlorobenzene. A certain mass of the above-mentioned chlorobenzene compound and the solvent are mixed uniformly to obtain a solution of the hole transport layer material, with a solute concentration of 2-15 mg / mL, preferably 8 mg / mL; the spin-coating speed is 2000-6000 rpm, more preferably 3000-4000 rpm; the spin time is 20-60 s, more preferably 30-50 s. After spin-coating the hole transport layer, the solvent needs to be removed. The selected methods are vacuum drying, heating drying under a nitrogen atmosphere, or heating drying in air, preferably vacuum drying and heating drying in air, with a heating temperature of 70-105°C and a heating time of 2-10 minutes.

[0074] The metal electrode layer was prepared by vacuum evaporation; the vacuum evaporation pressure was 5 × 10⁻⁶. -4 Pa. The metal electrode layer is preferably a gold layer, and the size of the gold electrode is specifically controlled by a photomask; the size of the gold electrode is 0.10 cm. 2 .

[0075] After depositing a metal electrode layer, heat treatment is performed to obtain a perovskite-based solar cell. The heat treatment temperature is 80–90°C, preferably 85°C; the heat treatment time is 2–100 h, preferably 3–72 h.

[0076] To further illustrate the technical solution of this application, the hole transport layer material of a solar cell, a perovskite-based solar cell and its preparation method provided in this application are described in detail below with reference to embodiments, but these should not be construed as limiting the scope of protection of this invention.

[0077] Example 1

[0078] The preparation method of the argan compound POTBC(Eu)4:2,9(10),16(17),23(24)-tetra(4-allyl-2-methoxyphenoxy)-triazatetrabenzoargan includes the following steps:

[0079] S11: Synthesis of phthalocyanine precursor H2Pc(Eu)4: 2,9(10),16(17),23(24)-tetra(4-allyl-2-methoxyphenoxy)-phthalocyanine:

[0080] 5 mL of n-pentanol was added to a 50 mL three-necked flask, and N2 gas was bubbled through the flask with stirring for ten minutes. Lithium metal (40 mg, 5 mmol) was added, and the temperature was raised to 90 °C. 0.29 g (1 mmol) of 4-(4-allyl-2-methoxyphenoxy)phthalonitrile was added, and the mixture was reacted at 140 °C for 4 hours to give a deep blue product. After cooling, a mixture of methanol / concentrated hydrochloric acid (5 mL, 1:1 v / v) was added, the precipitate was collected, and the mixture was filtered and washed with water. The dried product was purified by column chromatography (400 mesh silica, CH2Cl2 as eluent). The yield was 0.20 g (67%), and the product was characterized by mass spectrometry and NMR.

[0081] S12: Synthesis of POTBC(Eu)4:

[0082] 10 mL of pyridine containing the phthalocyanine precursor H₂Pc(Eu)₄ (1.16 g, 1.0 mmol) was added to a 50 mL three-necked round-bottom flask equipped with a reflux condenser and an argon inlet. After purging with argon for 10 min, 5 mL of pyridine containing PBr₃ (3.2 mL, 35 mmol) was added, and the mixture was heated at 95 °C with stirring under an argon atmosphere for 1 h. After cooling, the mixture was poured into water to precipitate and filtered. The solid was thoroughly washed with water. The crude product was dissolved in dichloromethane (DCM) and purified by column chromatography on silica gel using DCM / chloroform as the eluent. Yield: 0.69 g (58%), characterized by mass spectrometry and NMR.

[0083] Figure 1 This is a mass spectrum obtained by POTBC(Eu)4 electrospray ionization (ESI HRMS) assay, with CDCl3 as the solvent. Figure 2 It is POTBC(Eu)4 1 H NMR spectrum, solvent d 6 -DMSO. Figure 3 It is POTBC(Eu)4 31 P-NMR spectrum, solvent CDCl3. The results showed that 2,9(10),16(17),23(24)-tetra(4-allyl-2-methoxyphenoxy)-triazatetrabenzoxanor was finally obtained; Figure 4 This is the UV-Vis absorption spectrum of POTBC(Eu)4 in tetrahydrofuran (THF).

[0084] Example 2

[0085] The preparation method of the anthraquinone compound POTBC(β-OBu)8 [2,3,9,10,16,17,23,24-octabutoxytriazatetrabenzoxophosphorus anthraquinone] includes the following steps:

[0086] Synthesis of S21:H2Pc(β-OBu)8[2,3,9,10,16,17,23,24-octabutoxymetal-free phthalocyanine]

[0087] 6 mL of dry n-pentanol was added to a three-necked flask, and argon gas was introduced for protection. The temperature was controlled at approximately 80 °C, and then lithium metal (28 mg, 4 mmol) was added. After the lithium metal was completely dissolved, 4,5-dibutoxyphthalonitrile (1.09 g, 4 mmol) was added, and the mixture was heated to reflux for 4 h. After the reaction was complete, the mixture was cooled to room temperature (25–27 °C), and then 100 mL of methanol and 3–8 drops of concentrated hydrochloric acid were added. The mixture was stirred for 5 min and then filtered. The filter cake was washed with methanol until the filtrate was colorless. The resulting green solid was separated by column chromatography (silica gel 100–160 mesh) using CH₂Cl₂ as the eluent. The green component was collected, and the final amount collected was 0.288 g (yield 26.4%).

[0088] H2Pc(β-OBu)8IR(KBr) / cm -1 :1020,1097,1201,1280(νAr-OC);738,852,1460,1498,1597(νPc ring);1386,2869,2934,2964(νCH2 and CH3);3294(νN-H);UV / vis(DMF)λ max / nm:349,423,604,665,702. MALDI-TOF-MS (m / z) cal.:1091.3 found:1090.3 [MH] + .

[0089] Synthesis of S22: POTBC(b-OBu)8[2,3,9,10,16,17,23,24-octabutoxytriazatetrabenzoxophosphorus]

[0090] H₂Pc(β-OBu)₈ (0.5 g, 0.46 mmol) was dissolved in 5 mL of dry pyridine at room temperature. Under argon protection, 3 mL of dry pyridine containing PBr₃ (1.30 mL, 13.7 mmol) was added. After stirring briefly, the mixture was heated to 90-95 °C and reacted for 8 h. After the reaction was complete, the reactants were cooled to room temperature, then distilled water was added, stirred, and filtered. The filter cake was washed with distilled water until the filtrate was colorless. After drying, the resulting dark green solid was separated by column chromatography (silica gel 100-160 mesh) using CH₂Cl₂ / ethanol = 92:8 as the eluent. The green component was collected. The eluent for column chromatography was CH₂Cl₂ / ethanol = 96:4. The final green component collected was 0.23 g (yield 44.7%).

[0091] POTBC(β-OBu)8IR(KBr) / cm -1 :1020,1073,1109,1205,1257(νAr-OC);713,813,1469,1488,1613(νPc ring);1393,2862,2923,2960(νCH2 and CH3);UV / vis(DMF)λ max / nm:414,441,595,623,652. MALDI-TOF-MS (m / z) cal.:1122.3 found:1121.7 [MH] + .

[0092] Example 3

[0093] A method for preparing the anthraquinone compound POTBC(β-Bu)8 [2,3,9,10,16,17,23,24-octabutyltriazatetrabenzo[anthraquinone]] includes the following steps:

[0094] First, 0.2 mL of PBr3 was added to pyridine (2 mL). Under an argon atmosphere, the resulting solution was added to a pyridine suspension of H2Pc(β-Bu)8[2,3,9,10,16,17,23,24-octabutylmetal-free phthalocyanine] (50 mg, 0.052 mmol). The mixture was heated to 90–100 °C and stirred until the phthalocyanine precursor was completely reacted (1 h, monitored by TLC). The mixture was then cooled to approximately 20 °C and poured into water. The precipitate was filtered, washed with water, and finally washed with methanol (3 × 30 mL) and dried under vacuum. 35 mg (70%) of the product was obtained as a dark green powder. MS, m / z: 993.1 [M] + UV-Vis absorption spectra (solvent pyridine), maximum absorption wavelength nm (relative intensity): 664 (1.0), 636 (0.55), 605 (0.28), 448 (1.8), 417 (0.71).

[0095] Example 4

[0096] A perovskite solar cell includes a transparent conductive substrate (FTO), an electron transport layer (TiO2), and a perovskite light-absorbing layer (Cs) sequentially disposed thereon. 0.05 FA 0.81 MA 0.14 PbI 2.55 Br 0.45 The material comprises a hole transport layer (POTBC(Eu)4 in Example 1) and a metal electrode layer (Ag). Its preparation method includes:

[0097] (1) Fabrication of electron transport layer:

[0098] First, prepare a dense TiO2 layer (cp-TiO2): Prepare a 0.15 mol / L solution of diisopropoxytitanium bis-(acetylacetone) in 1-butanol. -1 The coating was applied to FTO glass by rotating at 2000 rpm for 60 seconds, and then heated at 125°C for 5 minutes. The above spin coating process was repeated to prepare a non-porous dense TiO2 film, and then the substrate was calcined in a box furnace at 450°C for 30 minutes.

[0099] Next, a mesoporous TiO2 layer (mp-TiO2) was prepared by spin coating with a TiO2 ethanol dispersion containing 14.3 wt% TiO2 paste at 4000 rpm for 20 s, depositing a mesoporous TiO2 (mp-TiO2) layer on the cp-TiO2 layer, and then calcining at 500 °C for 0.5 h.

[0100] (2) Preparation of perovskite light-absorbing layer:

[0101] Preparation of perovskite layer precursor solution: 172 mg FAI, 507 mg PbI2, 22.4 mg MABr, and 73.4 mg PbBr2 were dissolved in 1 mL of a mixed solvent of DMF and DMSO (9:1 volume ratio). Then, 1.5 M CsI dimethyl sulfoxide stock solution was added to the mixed perovskite precursor to obtain CsI. 0.05 FA 0.81 MA 0.14 PbI 2.55 Br 0.45 Precursor solution.

[0102] Perovskite films were deposited onto TiO2 substrates using a two-step spin-coating process. The first step involved spin-coating at 1000 rpm for 10 seconds with an acceleration of 500 rpm / s. The second step involved continuing spin-coating at 4000 rpm for 35 seconds with an acceleration of 2000 rpm / s. During this spin-coating process, chlorobenzene (~100 μL) was rapidly dropped onto the substrate 15 seconds before the end of the process. The prepared film was then heated at 100°C for approximately 2 hours until its color turned deep red.

[0103] (3) Preparation of hole transport layer:

[0104] 10 mg of POTBC(Eu)4 from Example 1 was weighed and dissolved in chlorobenzene to obtain a hole transport material solution of 10 mg / mL. The solution was spin-coated at 3000 rpm for 30 s, and then heated to remove the solvent.

[0105] (4) Fabrication of the metal electrode layer:

[0106] In 4×10 -5 Under vacuum, gold (Ag) is thermally evaporated at 0.05 nm / s to form electrodes, thus completing the device fabrication.

[0107] Performance testing

[0108] After the cell fabrication was completed, the cross-section of the obtained perovskite solar cell was analyzed by scanning electron microscopy, and the results are as follows: Figure 5 The image shown is a cross-sectional SEM image of a perovskite solar cell, with a hole transport layer (HTL) film thickness of 110 nm.

[0109] This application uses the commercially available Spiro-OMeTAD as a comparison (except for the hole transport layer, everything else is the same as the perovskite solar cell in Example 2). Figure 6 The JV curves for the perovskite solar cell used in Example 2 are shown in Table 1; Table 1 shows the test data using SpiroOMeTAD as the hole transport layer for comparison.

[0110] Table 1

[0111] SpiroOMeTAD 17.8 0.97 59.0 10.7 <![CDATA[POTBC(Eu)4]]> 21.7 0.89 62.1 12.1

[0112] *Scan rate 0.05V / s, test data is the average value of 9 battery devices obtained using the same method.

[0113] As can be seen from the above, the hole transport layer material of the solar cell in this embodiment of the application possesses good stability, high conductivity, and high hole mobility. Experimental results show that the short-circuit current density of the solar cell in this embodiment of the application is 21.7 mA / cm². 2 The fill factor is 62.1%, and the photoelectric conversion efficiency is 12.1%.

[0114] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A compound of the oxalis class, characterized in that, The general molecular structure of the aforementioned compounds is shown in Formula I: Wherein, R1 is selected from 4-allyl-2-methoxyphenoxy, R2 is selected from hydrogen atom, or R1 is selected from butyl, R2 is selected from butyl; L1 is selected from hydroxyl, L2 is selected from hydroxyl.

2. The method for preparing the oxalis compound as described in claim 1, characterized in that, Includes the following steps: 4-R1-5-R2-phthalonitrile and lithium metal were mixed and subjected to a first reaction to obtain the intermediate shown in Formula II; The intermediate shown in Formula II was mixed with phosphorus tribromide to carry out a second reaction, yielding the oxalis compound shown in Formula I. 。 3. The method for preparing the anthocyanin-like compound as described in claim 2, characterized in that, The molar ratio of the 4-R1-5-R2-phthalonitrile to the lithium metal is 1:4~6; and / or, The molar ratio of the intermediate shown in Formula II to the phosphorus tribromide is 1:32~38.

4. The method for preparing the oxalis compound as described in claim 2, characterized in that, The first reaction is carried out at a temperature of 120-160°C for 3-5 hours; and / or, The temperature of the second reaction is 90~100℃, and the time is 0.5~1.5h.

5. The method for preparing the oxalis compound according to any one of claims 2-4, characterized in that, The first reaction is carried out in an alkanolic solvent; and / or, The second reaction is carried out in a pyridine solvent.

6. The application of the horn-like compounds as described in claim 1 and / or the horn-like compounds prepared by the preparation method according to any one of claims 2-5 as hole transport materials.

7. A solar cell comprising a positive electrode and a negative electrode disposed opposite to each other, and a semiconductor layer located between the positive electrode and the negative electrode, wherein a hole transport layer is disposed between the semiconductor layer and the positive electrode, characterized in that, The material of the hole transport layer is the horro-like compound of claim 1 and / or the horro-like compound prepared by the preparation method of any one of claims 2-5.

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