Organic molecular compound based on alkoxy phosphonic acid as well as synthesis method and application of organic molecular compound

Abstract

The invention belongs to the field of organic photoelectric materials, and particularly relates to an organic molecular compound based on alkoxy phosphonic acid, a synthesis method of the organic molecular compound and application of the organic molecular compound in the field of photoelectric devices such as perovskite solar cells. The molecular structure of the compound is shown in the following formula (I), substituent groups are recorded in the specification, and the self-assembled molecule based on the alkoxy phosphonic acid unit can be used as a hole transport interface material to be applied to preparation of novel photoelectric devices such as perovskite solar cells, organic solar cells, organic photoelectric detectors and organic light-emitting diodes. The interface energy level and interface contact can be effectively regulated and controlled, rapid charge optimization extraction is achieved, and the photoelectric performance and long-term operation stability of a photoelectric device are improved. # imgabs0 #

Description

Technical Field

[0001] The present invention belongs to the field of organic photoelectric materials, and specifically relates to an alkoxyphosphonic acid-based organic molecular compound and a synthesis method thereof, and applications in the field of photoelectric devices such as perovskite solar cells. Background Art

[0002] With the continuous development of society, people's demand for energy is increasing. Due to the limited reserves of traditional fossil energy and the large amount of carbon dioxide emissions generated during its use, causing the global greenhouse effect, countries are competing to develop new renewable energy utilization technologies. Solar cells can convert solar energy into electrical energy and are an important green renewable energy device. In recent years, with the continuous advancement of technology, energy conversion efficiency has been continuously improved. Photoelectric devices using perovskite or organic semiconductors as light-absorbing layers have the advantages of simple preparation methods and low costs. They have developed particularly rapidly and have shown great application prospects in the field of portable and flexible electronic devices.

[0003] For example, inverse perovskite solar cell devices have small hysteresis effect, simple preparation method, good long-term stability of the device, and have better commercialization potential. The hole transport layer in the inverse device plays an important role in the photovoltaic performance of the device. The organic small molecule self-assembled monolayer (SAM) with anchoring groups can be used as an efficient hole transport layer to improve the performance and operation stability of photovoltaic devices. Compared with inorganic materials, it has better batch stability, energy level adjustability and multifunctionality. It can passivate the surface and interface defects of perovskite, adjust the morphology of the active layer, promote charge collection and extraction, and finally obtain efficient and stable battery devices.

[0004] Alkyl-substituted phosphonic acid molecules are currently commonly used self-assembly materials, such as 2PACz, MeO-2PACz, Me-4PACz, etc. The phosphonic acid groups can react with the hydroxyl groups on the surface of conductive oxides (such as indium tin oxide) and anchor on the electrode surface to form a monolayer, which can adjust the energy level between the electrode and the perovskite and improve the charge collection. However, this method of single-molecule modification still has some defects, such as it is difficult to ensure the uniformity of the monolayer, the binding force of the monolayer is not strong enough and it is easy to peel off. Therefore, it is still necessary to develop new interface modification materials to further improve the efficiency and stability of solar cell devices. Summary of the invention

[0005] The present invention provides an alkoxyphosphonic acid-based organic molecule compound and a synthesis method thereof, and applications in the field of optoelectronic devices such as perovskite solar cells.

[0006] An organic molecule compound based on alkoxyphosphonic acid, the molecular structure of the compound is shown in the following formula (I):

[0007]

[0008] Wherein, Ar is selected from C3-C10 cycloalkyl, C5-C60 aromatic ring, C5-C60 heteroaromatic ring which are unsubstituted or substituted by at least one identical or different substituent as follows, wherein the substituent is H, halogen, cyano, nitro, C1-C10 alkyl, C1-C10 alkoxy, C1-C10 haloalkyl, C1-C10 haloalkoxy, diphenylamino, C2-C10 alkenyl or C1-C10 alkylthio; m is selected from natural numbers of 0 to 20; and n is selected from natural numbers of 1-16.

[0009] In the compound formula (I), Ar is selected from the following structural units or structural units substituted by at least one identical or different substituent; the following substituent is H, halogen, cyano, nitro, C1-C10 alkyl, C1-C10 alkoxy, C1-C10 haloalkyl, C1-C10 haloalkoxy, diphenylamino, C2-C10 alkenyl or C1-C10 alkylthio; m is selected from natural numbers of 0 to 20; n is selected from natural numbers of 1 to 16;

[0010]

[0011] The dotted lines in the above structural units represent the connection sites with other units. The other units may be phosphonic acid side chains shown in structural formula (I) or may be substituent groups.

[0012] In the compound formula (I), Ar is selected from the Ar structural unit described in claim 2 or the Ar structural unit described in claim 2 substituted by at least one of the following substituents which are the same or different; the following substituents are H, halogen, C1-C8 alkyl, C1-C8 alkoxy, C1-C8 haloalkyl, C1-C8 haloalkoxy, diphenylamino, C2-C8 alkenyl or C1-C8 alkylthio; m is selected from natural numbers of 0 to 20 (i.e., 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20); n is selected from natural numbers of 1 to 16 (i.e., 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16);

[0013] A method for preparing the alkoxyphosphonic acid-based organic molecule compound is obtained by the following synthesis method:

[0014]

[0015] The alcohol compound represented by formula (A) is used as a raw material, reacted with trichlorophosphine oxide, and hydrolyzed with NaOH to obtain a compound represented by formula (I); the substituents of the raw material compound are the same as those described in claim 1.

[0016] An application of the alkoxyphosphonic acid-based organic molecular compound, and an application of the alkoxyphosphonic acid-based organic molecular compound as a hole transport layer material.

[0017] The compound is used as a self-assembled hole transport layer material in a novel optoelectronic device.

[0018] The novel optoelectronic device is a perovskite solar cell, an organic solar cell, an organic electroluminescent device, an organic field effect transistor or an organic detector.

[0019] A solar cell device comprises an anode, a cathode, an interface modification layer and a photoactive layer, wherein the material of the interface modification layer contains the alkoxyphosphonic acid-based organic molecular compound.

[0020] Compared with the prior art, the characteristics and advantages of the present invention are as follows: the organic compound based on alkoxyphosphonic acid unit provided by the present invention has the advantages of strong binding force, uniform distribution and good stability relative to the organic hole transport material of the existing trans-perovskite battery, and can obtain efficient and stable perovskite battery devices.

[0021] The application of the interface modification material based on alkoxyphosphonic acid molecules in the following optoelectronic devices includes but is not limited to perovskite solar cells, organic solar cells, organic electroluminescent devices, organic field effect transistors, organic detectors and optoelectronic devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 is the H NMR spectrum of compound 4.

[0023] Figure 2 This is the electrochemical cyclic voltammetry curve of compound 4.

[0024] Figure 3 is the UV-visible absorption spectrum of compound 4.

[0025] Figure 4 JV curve of perovskite solar cell with compound 4 as interface material. DETAILED DESCRIPTION

[0026] In order to better illustrate the content of the present invention, the technical scheme of the present invention is further illustrated by specific examples below, including the synthesis and characterization of materials, device preparation and performance research, etc. The examples given do not limit the protection scope of the present invention.

[0027] The self-assembled molecules based on alkoxyphosphonic acid units of the present invention can be used as hole transport interface materials in the preparation of new optoelectronic devices such as perovskite solar cells, organic solar cells, organic photodetectors, and organic light-emitting diodes. They can effectively regulate interface energy levels and interface contacts, achieve rapid charge optimization extraction, and improve the optoelectronic performance and long-term operating stability of optoelectronic devices.

[0028] Embodiment 1:

[0029]

[0030] Compound 1 (1.0 g) was dissolved in 20 mL of acetone, and NaH (352 mg, 60%) was added. The mixture was stirred at room temperature for 30 minutes, and 1,4-dibromobutane (1.14 g) was added. The mixture was heated under reflux for 12 hours, and then water was added. The mixture was extracted with ethyl acetate, dried, concentrated, and purified by column chromatography to obtain compound 2 (0.92 g).

[0031] Compound 2 (600 mg) was dissolved in 10 ml of 10% H 2 The reaction mixture was heated at 120°C for 10 h in O / NMP, extracted with ethyl acetate, dried, concentrated and purified by column chromatography to obtain compound 3 (280 mg). 1 H NMR(600MHz,Chloroform-d)δ8.12(d,J=2.0Hz,2H),7.54(dd,J=8.6,1.9Hz,2H),7.28-7.22 (m,2H),4.28(t,J=7.1Hz,2H),3.62(t,J=6.3Hz,2H),1.96-1.88(m,2H),1.58-1.50(m,2H).

[0032] To a solution of compound 3 (102 mg) in tetrahydrofuran (10 ml) was added trichlorophosphine (80 mg) and triethylamine (53 mg), stirred at room temperature for 2 hours, then 1.6 mL of 2M sodium hydroxide solution was added, and stirred at room temperature for 10 hours. The reaction solution was adjusted to pH = 1 with 2M hydrochloric acid, extracted and concentrated with ethyl acetate, and recrystallized from methanol / water to obtain the target compound 4 (65 mg). 1 H NMR (600 MHz, Methanol-d 4 )δ8.09(d,J=1.9Hz,2H),7.45(dd,J=8.7,2.0Hz,2H),7.36(d,J=8.7Hz,2H),4.27(t,J= 7.3Hz, 2H), 3.86 (q, J=6.3Hz, 2H), 1.84 (ddd, J=9.2, 6.2, 2.2Hz, 2H), 1.62-1.54 (m, 2H).

[0033] Other molecules can be obtained according to similar steps as above, which will not be described in detail here.

[0034] Example 2: Preparation and characterization of perovskite solar cell devices

[0035] The compound 4 obtained in the above example is used as the anode interface material to make a perovskite solar cell device, and the steps are as follows:

[0036] The ITO glass was ultrasonically cleaned with a cleaning agent, ultrapure water, acetone, and isopropanol for 20 minutes, dried with nitrogen, and treated with oxygen plasma for 20 minutes, and then spin-coated with a 10 mg / mL nickel oxide nanoparticle aqueous solution, annealed at 150 degrees for 10 minutes, and transferred to a glove box. An ethanol solution (0.5 mg / mL) of the compound of formula (I) was spin-coated on the nickel oxide film and annealed at 100°C for 10 minutes to prepare a hole transport layer substrate.

[0037] 228.7 mg FAI, 18.2 mg cesium iodide, and 645.4 mg lead iodide were dissolved in a DMF / DMSO (volume 1 ml) mixed solvent to prepare a 1.4 M perovskite precursor solution, and stirred at room temperature for 4 hours. The solution was spin-coated on the above-mentioned hole transport layer substrate, and chlorobenzene was spin-coated 5 seconds before the end of spin coating. The perovskite film was annealed at 100°C for 10 minutes to obtain a perovskite film. Finally, PCBM solution and bath copper (BCP) solution were spin-coated on the perovskite film in sequence, and silver (100 nm) was vacuum evaporated as the cathode electrode to complete the preparation of the perovskite solar cell.

[0038] The perovskite solar cell was placed under simulated sunlight of AM1.5 (100mW / cm 2 ) for performance testing, and its current density-voltage curve is as follows Figure 4 As shown in Figure 2, with compound 4 as the hole transport layer, the open circuit voltage of the battery is 1.13 V and the short circuit current density is 24.71 mA cm -2 The fill factor is 82.0%, the photoelectric conversion efficiency is 22.9%, and the device performance is significantly higher than that of the commercially available hole transport material 2PACz, with an open circuit voltage of 1.10 V and a short circuit current density of 23.88 mA cm -2 , the filling factor is 80.0%, and the photoelectric conversion efficiency is 21.0%, which shows that alkoxyphosphonic acid molecules are a new type of efficient interface material that can effectively improve the performance of optoelectronic devices such as perovskite.

Claims

1. An organic molecule compound based on alkoxyphosphonic acid, characterized in that: The molecular structure of the compound is shown in the following formula (I): Wherein, Ar is selected from C3-C10 cycloalkyl, C5-C60 aromatic ring, C5-C60 heteroaromatic ring which are unsubstituted or substituted by at least one identical or different substituent as follows, wherein the substituent is H, halogen, cyano, nitro, C1-C10 alkyl, C1-C10 alkoxy, C1-C10 haloalkyl, C1-C10 haloalkoxy, diphenylamino, C2-C10 alkenyl or C1-C10 alkylthio; m is selected from natural numbers of 0-20; and n is selected from natural numbers of 1-16.

2. The alkoxyphosphonic acid organic molecule compound according to claim 1, characterized in that: In the compound formula (I), Ar is selected from the following structural units or structural units substituted by at least one identical or different substituent; the following substituent is H, halogen, cyano, nitro, C1-C10 alkyl, C1-C10 alkoxy, C1-C10 haloalkyl, C1-C10 haloalkoxy, diphenylamino, C2-C10 alkenyl or C1-C10 alkylthio; m is selected from natural numbers of 0 to 20; n is selected from natural numbers of 1 to 16; 3. The alkoxyphosphonic acid organic molecule compound according to claim 2, characterized in that: In the compound formula (I), Ar is selected from the Ar structural unit recorded in claim 2 or the Ar structural unit recorded in claim 2 substituted by at least one of the following identical or different substituents; the following substituents are H, halogen, C1-C8 alkyl, C1-C8 alkoxy, C1-C8 haloalkyl, C1-C8 haloalkoxy, diphenylamino, C2-C8 alkenyl or C1-C8 alkylthio.

4. A method for preparing an alkoxyphosphonic acid organic molecule compound according to claim 1, characterized in that: Obtained by the following synthetic method: The alcohol compound represented by formula (A) is used as a raw material, reacted with trichlorophosphine oxide, and hydrolyzed with NaOH to obtain a compound represented by formula (I); the substituents of the raw material compound are the same as those described in claim 1.

5. An application of an alkoxyphosphonic acid organic molecule compound according to claim 1, characterized in that: The invention relates to the use of alkoxyphosphonic acid compounds as hole transport materials.

6. The use of an alkoxyphosphonic acid organic molecule compound according to claim 5, characterized in that: The compound is used as a self-assembled hole transport layer material in a novel optoelectronic device.

7. The use of an alkoxyphosphonic acid organic molecule compound according to claim 6, characterized in that: The novel optoelectronic device is a perovskite solar cell, an organic solar cell, an organic electroluminescent device, an organic field effect transistor or an organic detector.

8. A solar cell device comprising an anode, a cathode, an interface modification layer and a photoactive layer, characterized in that: The material of the interface modification layer contains the alkoxyphosphonic acid-based organic molecule compound according to claim 1.

Images