A multiple resonance type non-fullerene acceptor material, a preparation method and application thereof

Abstract

The application belongs to the field of organic photovoltaic materials, and relates to a multiple resonance type non-fullerene acceptor material, a preparation method and application, the multiple resonance type non-fullerene acceptor material has the structures shown in general formula I and general formula II. The multiple resonance type non-fullerene acceptor material provided by the application has a maximum absorption edge of 812 nm, and a molar absorption coefficient as high as 6.01*10 4 M ‑ 1 cm ‑1 , and simultaneously has a deep LUMO energy level, the lowest being -3.62 eV.

Description

Technical Field

[0001] This invention belongs to the field of organic photovoltaics, specifically relating to a multi-resonance non-fullerene acceptor material, its preparation method, and its applications. Background Technology

[0002] Organic solar cells (OSCs), as a new generation of photovoltaic technology, have significant advantages over traditional silicon-based and inorganic thin-film solar cells, such as simple fabrication process, light weight, flexibility, and the ability to realize semi-transparent devices. They demonstrate important research value and broad application prospects, and are an important research direction in the current photovoltaic field.

[0003] In bulk heterojunction OSCs, the acceptor material is one of the key components determining device performance, and its system has evolved from fullerene derivatives to the currently mainstream ADA-type non-fullerene acceptors. However, fullerene acceptors have inherent limitations such as weak absorption in the visible light region and difficulty in energy level tuning; while ADA-type non-fullerene acceptors, although achieving narrow band gaps and strong absorption, often suffer from significant nonradiative voltage losses due to nonradiative recombination caused by triplet excitons, which restricts further improvements in device photoelectric conversion efficiency and long-term stability. Currently, the structural types of high-performance non-fullerene acceptors remain relatively limited.

[0004] Therefore, developing non-fullerene acceptor material systems with novel structural features is of great significance for overcoming existing technological bottlenecks and promoting breakthroughs in OSC performance. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to provide a multi-resonance non-fullerene acceptor material, its preparation method, and its applications. A series of non-fullerene acceptor materials with multi-resonance properties were designed and synthesized. This provides a new molecular system for developing novel non-fullerene acceptor materials with high absorption intensity, broad spectral response, and good photoelectric properties.

[0006] To achieve this objective, the present invention adopts the following technical solution:

[0007] On one hand, the present invention provides a multi-resonance non-fullerene acceptor material, wherein the multi-resonance non-fullerene acceptor material has the structures shown in general formulas I and II as follows:

[0008]

[0009] Among them, R 1 ~R 8 Selected from hydrogen, deuterium, C1~C30 chain alkyl, C3~C30 cycloalkyl, C1~C10 alkoxy, and C1~C10 thioalkyl;

[0010] Ar 1~Ar 2 Selected from one of C6-C30 aryl groups and C3-C30 heteroaryl groups;

[0011] When Ar has substituents, they are independently selected from one of the following: deuterium, halogen, hydroxyl, carboxyl, cyano, nitro, trifluoromethyl, alkynyl, C1-C30 chain alkyl, C3-C30 cycloalkyl, C1-C10 alkoxy, C6-C30 acyl, C6-C30 arylamino, C3-C30 heteroarylamino, C6-C30 aryl, and C3-C30 heteroaryl.

[0012] Furthermore, the compounds of general formula I and general formula II described in this invention are preferably configured to have the structures shown in general formulas III and IV as follows:

[0013]

[0014] Preferably, the multiple resonance non-fullerene receptor is selected from compounds with the following specific structures:

[0015]

[0016]

[0017] On the other hand, the present invention provides a method for preparing a multiple resonance non-fullerene acceptor material as described above, wherein the preparation methods of general formula I and general formula II include the following steps:

[0018] (1) Reactant A and thiophene monomer are dissolved in a solvent and reacted in the presence of a transition metal catalyst, an additive, and a base to obtain intermediate B. The general reaction formula is as follows:

[0019]

[0020] (2) Intermediate B was dissolved in a solvent and reacted in the presence of additives and solvent to obtain intermediates C-1 and C-2, which were then separated by column chromatography. The reaction formula is as follows:

[0021]

[0022] (3) Dissolve intermediate C-1 or intermediate C-2 in a solvent and react in the presence of anhydride and Lewis acid to obtain multiple resonance nonfullerene receptor I and receptor II, as shown in the following reaction formula:

[0023]

[0024]

[0025] Preferably, steps (1), (2), and (3) are all carried out in a protective atmosphere, wherein the protective atmosphere is nitrogen or argon.

[0026] Preferably, the molar ratio of reactant A to thiophene monomer in step (1) is 1.0:4.0~6.0.

[0027] Preferably, the solvent for the reaction in step (1) is selected from one or at least two of 1,4-dioxane, toluene, benzene, xylene, mesitylene, or N,N-dimethylformamide, and a combination of water. The mass of the solvent is 10 to 100 times the mass of reactant A.

[0028] Preferably, the transition metal catalyst in step (1) is selected from one or more of palladium acetate, palladium chloride, tetra(triphenylphosphine)palladium, bis(triphenylphosphine)palladium dichloride, 1,1'-bis(diphenylphosphine)ferrocene palladium dichloride or tris(dibenzylideneacetone)palladium; the molar ratio of the transition metal catalyst to reactant A is 0.05~1.0∶1.0.

[0029] Preferably, the additive used in step (1) is selected from one or more of the following: triphenylphosphine, tricyclohexylphosphine, tri-tert-butylphosphine, tris(o-methylphenyl)phosphine, 2-dicyclohexylphosphine-2',6'-dimethoxybiphenyl, 4,5-bis(diphenylphosphine-9,9-dimethyloxanthracene, 2-dicyclohexylphosphine-2',4',6'-triisopropylbiphenyl, 2-dicyclohexylphosphine-2',6'-diisopropoxy-1,1'-biphenyl, and 1,1'-bis(diphenylphosphine)ferrocene; the molar ratio of the additive to reactant A is 0.05~2.0∶1.0.

[0030] Preferably, the base used in the reaction of step (1) is selected from one or more of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU), sodium tert-butoxide, potassium tert-butoxide, sodium carbonate, sodium bicarbonate, potassium carbonate, potassium phosphate, cesium carbonate, potassium acetate, and triethylamine; the molar ratio of the base to reactant A is 1.0~10.0∶1.0.

[0031] Preferably, the reaction temperature in step (1) is 70~180 ℃ and the reaction time is 8~72 h. More preferably, the reaction temperature is 80~150 ℃ and the reaction time is 12~36 h.

[0032] Preferably, the reaction additive in step (2) is selected from one or more of triphenylphosphine, tributylphosphine, trimethyl phosphite, triethyl phosphite, tris(diethylamino)phosphine, bismuth trifluoromethanesulfonate, and methanesulfonic acid, and the molar ratio of the additive to intermediate B is 0.1~20.0∶1.0.

[0033] Preferably, the reaction solvent in step (2) is selected from one or more of toluene, xylene, mesitylene, o-dichlorobenzene, diphenyl ether, dichloromethane, and dichloroethane; the mass of the solvent is 10 to 100 times the mass of intermediate B.

[0034] Preferably, the reaction temperature in step (2) is 0~200 ℃ and the reaction time is 6~72 h. More preferably, the reaction temperature is 0~180 ℃ and the reaction time is 12~72 h.

[0035] Preferably, the molar ratio of reaction intermediate C-1 or intermediate C-2 to IC derivative in step (3) is 1.0:4.0~6.0;

[0036] Preferably, the reaction solvent in step (3) is selected from one or more of benzene, toluene, xylene, ethanol, methanol, and acetonitrile; the mass of the solvent is 10 to 100 times the mass of intermediate C-1 or intermediate C-2.

[0037] Preferably, the acid in the reaction of step (3) is selected from one or more of boron trifluoride diethyl ether complex, β-alanine, and aluminum chloride, and the molar ratio of the acid to intermediate C-1 or intermediate C-2 is 0.01~0.05∶1.0.

[0038] Preferably, the dehydrating agent in step (3) is selected from one or more of acetic anhydride, propionic anhydride, trifluoroacetic anhydride, and phthalic anhydride. The molar ratio of the dehydrating agent to intermediate C-1 or intermediate C-2 is 0.01~0.05∶1.0.

[0039] Preferably, the reaction temperature in step (3) is 20~50 ℃ and the reaction time is 3~12 h. More preferably, the reaction temperature is 30~50 ℃ and the reaction time is 5~12 h.

[0040] The preparation method of reactant A includes the following steps, and the reaction formula is as follows:

[0041]

[0042] Compound 1, bis-pinacol boronic acid ester, tris(dibenzylacetone)dipalladium, 2-dicyclohexylphosphine-2',4',6'-triisopropylbiphenyl, and potassium acetate were dissolved in 1,4-dioxane, the mass of 1,4-dioxane being 10 to 100 times that of compound 1. The molar ratio of compound 1 to bis-pinacol boronic acid ester was 1.0:4.0 to 6.0; the molar ratio of compound 1 to tris(dibenzylacetone)dipalladium was 1.0:0.05 to 1.0; the molar ratio of compound 1 to 2-dicyclohexylphosphine-2',4',6'-triisopropylbiphenyl was 1.0:0.05 to 2.0; and the molar ratio of compound 1 to potassium acetate was 1.0:1.0 to 10.0. The reaction temperature was 70 to 130 °C, and the reaction time was 24 to 36 h. All the reactions described above were carried out under an inert atmosphere, selected from nitrogen or argon. Compound 1 can be obtained from (Ji-Kun Li, Xing-Yu Chen, Yun-Long Guo, Xin-Chang Wang, Andrew C.-H. Sue, Xiao-Yu Cao, Xiao-Ye Wang) , "B,N-Embedded Double Hetero[7]helicenes withStrong Chiroptical Responses in the Visible Light Region", J. Am. Chem. Soc 2021, 143 Synthesized using the method reported in , 17958).

[0043] The preparation method of thiophene monomer is as follows:

[0044]

[0045] R 9 Selected from halogen, hydroxyl, carboxyl, cyano, nitro, amino, trifluoromethyl, alkynyl, C1~C10 alkenylalkoxy, and C6~C30 acyl.

[0046] The reaction additives are selected from one or more of nitric acid, methoxymethyltriphenylphosphine chloride, ammonia, sodium cyanide, trimethylcyanosilane, malononitrile, tert-butyl isocyanate, nitromethane, and 1,2-ethylenedithiol.

[0047] The solvent for the reaction is selected from one or more of concentrated sulfuric acid, tetrahydrofuran, diethyl ether, dichloromethane, dichloroethane, methanol, toluene, and trimethylbenzene.

[0048] The molar ratio of reaction intermediate B to additive is 1.0:1.0~10.0; the reaction temperature is 0~100℃, and the reaction time is 6~24 h.

[0049] As a preferred technical solution, the preparation steps of general formula I and general formula II of the multiple resonance nonfullerene acceptor materials of the present invention are as follows:

[0050]

[0051] The specific preparation methods for general formulas I and II include the following steps:

[0052] (1) Synthesis of reactant A: Compound 1, bis-pinacol boronic acid ester, tris(dibenzylacetone) dipalladium and 2-dicyclohexylphosphine-2',4',6'-triisopropylbiphenyl (XPhos), potassium acetate were weighed, the mixture was purged 3 times, protected with argon, and ultra-dry 1,4-dioxane was added. The mixture was stirred and refluxed at 110 °C for 24 h. After the reaction was completed, the insoluble matter was filtered off, washed with dichloromethane, concentrated under reduced pressure, and separated by column chromatography to obtain reactant A.

[0053] (2) Synthesis of intermediate B: Weigh reactant A, thiophene monomer, bis(triphenylphosphine) palladium dichloride, potassium carbonate, evacuate the gas 3 times, protect with argon, add deoxygenated toluene and water (toluene to water ratio of 5:1), stir and reflux at 80 °C for 12 h, after the reaction is complete, extract with dichloromethane, combine the organic layers, dry with anhydrous magnesium sulfate, filter, concentrate under reduced pressure and then separate by column chromatography to obtain intermediate B;

[0054] (3) Synthesis of intermediate C-1 and intermediate C-2: Weigh intermediate B and additives, evacuate the gas 3 times, protect with argon, add ultra-dry solvent, heat and stir for 36 h, after the reaction is completed, concentrate under reduced pressure, and then perform column chromatography to obtain intermediate C-1 and intermediate C-2.

[0055] (4) Synthesis of multiple resonance nonfullerene receptor I and receptor II: Weigh intermediate C-1 or intermediate C-2, IC derivative, evacuate three times, protect with argon, add ultra-dry toluene, acetic anhydride, boron trifluoride diethyl ether complex, heat and stir at 30 °C for 6 h. After the reaction is complete, wash with water, extract with dichloromethane, combine the organic layers, dry with anhydrous magnesium sulfate, filter, concentrate under reduced pressure and separate by column chromatography to obtain the target compound as a purple solid.

[0056] Compared with the prior art, the present invention has the following beneficial effects:

[0057] 1. The non-fullerene acceptor material provided by this invention introduces multiple resonances into the acceptor core structure for the first time. By fused different aromatic ring structures, a series of novel non-fullerene acceptor materials can be rapidly obtained through Knoevenagel condensation reaction.

[0058] 2. The multi-resonance non-fullerene acceptor material provided by this invention successfully achieves a narrow bandgap, with an electrochemical bandgap of 1.30 eV and an optical bandgap of 1.53 eV. It exhibits strong absorption in the near-infrared region, with a molar extinction coefficient as high as 6.01 × 10⁻⁶. 4 M - 1 cm -1 Furthermore, these molecules exhibit a maximum absorption edge of 812 nm and a deep LUMO level of -3.62 eV. Such narrow-bandgap, multi-resonance non-fullerene acceptor materials hold immense promise for applications in organic optoelectronics, particularly in organic solar cells. Attached Figure Description

[0059] Figure 1 This is the absorption spectrum of the compound sym-ICINBN-NS of the present invention;

[0060] Figure 2 This is the fluorescence spectrum of the compound sym-ICINBN-NS of this invention;

[0061] Figure 3 This is the transient emission spectrum of the compound sym-ICINBN-NS of the present invention;

[0062] Figure 4 This is the electrochemical cyclic voltammetry curve of the compound sym-ICINBN-NS of this invention;

[0063] Figure 5 This is the absorption spectrum of the compound asym-ICINBN-NS of the present invention;

[0064] Figure 6 This is the fluorescence spectrum of the compound asym-ICINBN-NS of this invention;

[0065] Figure 7 This is the transient emission spectrum of the compound asym-ICINBN-NS of the present invention;

[0066] Figure 8 This is the electrochemical cyclic voltammetry curve of the compound asym-ICINBN-NS of this invention; Detailed Implementation

[0067] The present invention will be further described in detail below through specific embodiments. The following embodiments are merely descriptive and not limiting, and should not be used to limit the scope of protection of the present invention.

[0068] Example 1:

[0069]

[0070] Synthesis of Compound A: Compound 1 (Ji-Kun Li, Xing-Yu Chen, Yun-Long Guo, Xin-Chang Wang, Andrew C.-H. Sue, Xiao-Yu Cao, Xiao-Ye Wang) was added to a Shrek flask. , "B,N-Embedded Double Hetero helicenes with Strong Chiroptical Responses in theVisible Light Region", J. Am. Chem. Soc 2021, 143 Synthesized using the method reported in 17958). The reaction mixture consisted of: 1.5 g (0.80 mmol), bis-pinacol boronic acid ester (1.2 g, 4.80 mmol), tris(dibenzylacetone)palladium (Pd2(dba)3) (73 mg, 0.08 mmol), 2-dicyclohexylphosphine-2',4',6'-triisopropylbiphenyl (XPhos) (76 mg, 0.16 mmol), and potassium acetate (313 mg, 3.20 mmol). The mixture was purged three times under argon protection, and 50 mL of 1,4-dioxane was added. The mixture was stirred and refluxed at 110 °C for 24 h. After the reaction was complete, the insoluble matter was filtered off, washed with dichloromethane, concentrated under reduced pressure, and separated by column chromatography to obtain a blue oily reactant A (1.25 g, yield: 75%). 1 H NMR (400 MHz, C6D6, 297 K, ppm) δ 10.14 (s, 2H), 9.51 (s, 2H), 8.94 (s, 2H), 8.38 (s, 2H), 8.00 (s, 2H), 6.76-6.74 (d, J = 8.0 Hz, 2H), 6.61-6.59 (d, J = 8.0 Hz, 2H), 3.11-3.10 (d J = 4.0 Hz, 4H), 2.66-2.64 (d J= 8.0 Hz, 4H), 2.23 (s, 2H), 1.93 (s, 6H), 1.71-1.62 (m, 20H), 1.44 (s, 6H), 1.41-1.38 (m, 32H), 1.30-1.27 (m, 102H), 0.90-0.85 (m, 24H). HRMS (MALDI) m / z theoretical value: 2084.7037; experimental value: 2084.7046 [M+H] + .

[0071] Synthesis of compound B: Compound A (320 mg, 0.15 mmol), 4-nitro-5-bromo-2-thiophenecarboxaldehyde (177 mg, 0.75 mmol), bis(triphenylphosphine)palladium dichloride (35 mmol, 0.05 mmol), and potassium carbonate (166 mg, 1.20 mmol) were weighed out, purged three times, and protected with argon. Toluene and water (volume ratio of toluene to water was 5:1) were added, and the mixture was stirred and refluxed at 80 °C for 12 h. After the reaction was completed, the mixture was extracted with dichloromethane, the organic layers were combined, dried with anhydrous magnesium sulfate, filtered, concentrated under reduced pressure, and separated by column chromatography to obtain a dark green solid intermediate B (177 mg, yield: 55%). 1 H NMR (400MHz, C6D6, 297 K, ppm) δ 9.48 (s, 2H), 9.30 (s, 2H), 9.25 (s, 2H), 8.43 (s, 2H),8.02-7.99 (d, J = 12.0 Hz, 4H), 7.54 (s, 2H), 6.78-6.76 (d, J = 8.0 Hz, 2H), 6.65-6.63 (d J = 8.0 Hz, 2H), 3.22 (s 4H), 2.65-2.64 (d, J = 4.0 Hz, 4H), 2.22 (s, 2H), 1.95 (s, 6H), 1.59 (s, 2H), 1.50 (s, 6H), 1.36-1.27 (m, 128H), 0.90-0.88 (m, 24H). HRMS (MALDI) m / z theoretical value: 2142.4687; experimental value: 2142.4782 [M+H] + .

[0072] Synthesis of compound C-1: Compound B (480 mg, 0.22 mmol) and triphenylphosphine (577 mg, 2.20 mmol) were weighed, and the mixture was purged three times. Under argon protection, 10 mL of o-dichlorobenzene was added, and the mixture was stirred and refluxed at 180 °C for 36 h. After the reaction was completed, the mixture was concentrated under reduced pressure, and potassium iodide (10 mg, 0.06 mmol) and potassium carbonate (10 mg, 0.30 mmol) were added. The mixture was purged three times, and under argon protection, 5 mL of ultradry N,N-dimethylformamide and 11-bromomethyltetradecane (84 mg, 0.20 mmol) were added. The mixture was heated and stirred at 85 °C for 12 h. After the reaction was completed, the mixture was washed with water, extracted with dichloromethane, and the organic layers were combined and dried with anhydrous magnesium sulfate. The mixture was filtered, concentrated under reduced pressure, and separated by column chromatography to obtain a green oily compound C-1 (109 mg, yield: 18%). 1 H NMR (400 MHz, C6D6, 297 K, ppm) δ 9.99 (s, 2H), 8.85 (s, 2H), 8.44 (s, 2H), 8.21 (s, 2H), 8.11 (s, 2H), 7.76 (s, 2H), 6.90-6.88 (d, J = 8.0 Hz, 2H), 6.85-6.83 (d J = 8.0 Hz, 2H), 5.16-5.10 (m, 2H), 4.36-4.31 (m, 2H), 3.18-3.06 (m,4H), 2.86-2.82 (d, J = 16.0 Hz, 4H), 2.20-2.13 (m, 2H), 2.10-2.15 (m, 2H), 1.97 (s, 6H), 1.89 (s, 2H), 1.50 (s, 6H), 1.40-1.00 (m, 208H), 0.95-0.89 (m, 36H). HRMS (MALDI) m / z theoretical value: 2752.2515; experimental value: 2752.2576 [M+H] + .

[0073] Synthesis of the multi-resonance non-fullerene acceptor material sym-ICINBN-NS-1: Compound C-1 (55 mg, 0.02 mmol), 5,6-difluoro-3-(dicyanomethylene)indophenone (18 mg, 0.08 mmol) were weighed, and the mixture was purged three times under argon protection. 2 mL of toluene was added, followed by acetic anhydride (0.02 mg, 0.0002 mmol) and boron trifluoride diethyl ether complex (0.03 mg, 0.0002 mmol). The mixture was heated and stirred at 30 °C for 6 h. After the reaction was complete, the mixture was washed with water, extracted with dichloromethane, and the organic layers were combined and dried with anhydrous magnesium sulfate. The mixture was filtered, concentrated under reduced pressure, and then separated by column chromatography to obtain the target compound (25 mg, yield: 40%) as a purple solid. 1 H NMR (400 MHz, C6D6, 297 K, ppm) δ 9.14 (s, 2H), 8.91 (s, 2H),8.59-8.49 (m, 4H), 8.35-8.30 (m, 2H), 8.19 (s, 2H), 8.14 (s, 2H), 7.33-7.29(t, J = 16.0 Hz, 2H), 6.94-6.92 (d J = 8.0 Hz, 2H), 6.88-6.86 (d, 2H), 5.16-5.11(m, 2H), 4.48-4.42, (m, 2H), 3.23-3.14 (m, 4H), 2.86-2.84 (d, J = 8.0 Hz, 4H), 2.23 (s, 2H), 2.18-2.13 (m, 2H), 2.02 (s, 6H), 1.92 (s, 2H), 1.52 (s, 6H), 1.42-1.00 (m, 208H), 0.95-0.88 (m, 36H). HRMS (MALDI) m / z theoretical value: 3177.2931; experimental value: 3177.2891 [M+H] + .

[0074] Example 2:

[0075]

[0076] Synthesis of compound C-2: Compound B (545 mg, 0.25 mmol) and triphenylphosphine (656 mg, 2.50 mmol) were weighed, and the mixture was purged three times. Under argon protection, 10 mL of o-dichlorobenzene was added, and the mixture was stirred and refluxed at 180 °C for 36 h. After the reaction was completed, the mixture was concentrated under reduced pressure, and potassium iodide (15 mg, 0.09 mmol) and potassium carbonate (15 mg, 0.45 mmol) were added. The mixture was purged three times, and under argon protection, 5 mL of ultradry N,N-dimethylformamide and 11-bromomethyltetradecane (126 mg, 0.30 mmol) were added. The mixture was heated and stirred at 85 °C for 12 h. After the reaction was completed, the mixture was washed with water, extracted with dichloromethane, and the organic layers were combined and dried with anhydrous magnesium sulfate. The mixture was filtered, concentrated under reduced pressure, and separated by column chromatography to obtain the green oily compound C-2 (186 mg, yield: 27%). 1 H NMR (400 MHz, C6D6, 297 K, ppm) δ 9.99 (s, 1H), 9.92 (s, 1H), 9.79 (s, 1H),9.36 (s, 1H), 8.90 (s, 1H), 8.48 (s, 1H), 8.43 (s, 1H), 8.20 (s, 1H), 8.15(s, 1H), 8.05 (s, 1H), 7.75 (s, 1H), 7.45 (s, 1H), 6.96 (s, 2H), 6.85-6.83(d J = 8.0 Hz, 1H), 6.68-6.66 (d J = 8.0 Hz, 1H), 5.19-5.13 (m, 1H), 4.74-4.68(m, 1H), 4.33-4.24 (m, 2H), 3.22-3.10 (m, 4H), 2.96-2.84 (m, 2H), 2.75-2.73(m, 2H), 2.44-2.40 (m, 1H), 2.29 (s, 3H), 2.20-2.16 (m, 2H), 2.05-2.02 (m,1H), 1.96 (s, 3H), 1.80 (s, 2H),1.52-1.29 (m, 214H), 0.94-0.90 (m, 36H) HRMS(MALDI) Theoretical m / z value: 2752.2515; Experimental value: 2752.2527 [M+H] + .

[0077] Synthesis of the multi-resonance non-fullerene acceptor material asym-ICINBN-NS-1: Compound C-2 (82 mg, 0.03 mmol) and 5,6-difluoro-3-(dicyanomethylene)indophenone (27 mg, 0.12 mmol) were weighed, purged three times, and protected with argon. 2 mL of toluene was added, followed by acetic anhydride (0.03 mg, 0.0003 mmol) and boron trifluoride diethyl ether complex (0.04 mg, 0.0003 mmol). The mixture was heated and stirred at 30 °C for 6 h. After the reaction was complete, the mixture was washed with water, extracted with dichloromethane, and the organic layers were combined and dried with anhydrous magnesium sulfate. After filtration and concentration under reduced pressure, column chromatography was performed to obtain the target compound (36 mg, yield: 38%) as a purple solid. 1 H NMR (400 MHz, C6D6, 297 K, ppm) δ 9.54 (s, 1H), 9.23 (s, 1H), 9.06 (s, 1H), 8.83 (s, 1H), 8.79 (s, 1H), 8.44-8.41 (m, 3H), 8.34-8.30 (m,1H), 8.20 (s, 1H), 8.05 (s, 1H), 8.00 (s, 1H), 7.90-7.85 (m, 1H), 7.48-7.44(m, 1H), 7.36-7.30 (m, 1H), 6.82-6.74 (m, 4H), 6.57-6.55 (m, 1H), 4.99-4.94(m, 1H), 4.81 (s, 1H), 4.44-4.32 (m, 2H), 3.32 (s, 2H), 3.18-3.14 (m, 2H), 2.83-2.78 (m, 2H), 2.71-2.69 (m, 2H), 2.39 (s, 1H), 2.30 (s, 3H), 2.23 (s,1H), 2.16 (s, 1H), 2.06 (s, 3H), 1.99 (s, 1H), 1.76 (s, 2H), 1.66 (s, 3H), 1,52 (s, 3H), 1.38-1.18 (m, 208H), 0.91-0.88 (m, 36H). HRMS (MALDI) m / z Theoretical value: 3177.2931; Experimental value: 3177.2928 [M+H] + .

[0078] Example 3:

[0079]

[0080] Synthesis of compound C-3: Compound B (480 mg, 0.22 mmol) and triphenylphosphine (577 mg, 2.20 mmol) were weighed, and the mixture was purged three times. Under argon protection, 10 mL of o-dichlorobenzene was added, and the mixture was stirred and refluxed at 180 °C for 36 h. After the reaction was completed, the mixture was concentrated under reduced pressure, and potassium iodide (10 mg, 0.06 mmol) and potassium carbonate (10 mg, 0.30 mmol) were added. The mixture was purged three times, and under argon protection, 5 mL of ultradry N,N-dimethylformamide and bromoisooctane (39 mg, 0.20 mmol) were added. The mixture was heated and stirred at 85 °C for 12 h. After the reaction was completed, the mixture was washed with water, extracted with dichloromethane, and the organic layers were combined and dried with anhydrous magnesium sulfate. The mixture was filtered, concentrated under reduced pressure, and separated by column chromatography to obtain a green oily compound C-3 (101 mg, yield: 20%). 1 H NMR (400 MHz, C6D6, 297 K, ppm) δ 9.97 (s, 2H), 8.28 (s, 2H), 8.23 ​​(s,2H), 8.13 (s,2H), 7.81 (s, 2H), 7.77 (s, 2H), 6.50-6.48 (d, J = 8.0 Hz, 2H), 6.36-6.34 (d, J =8.0 Hz, 2H), 4.62-4.56 (m, 2H), 4.04-3.99 (m, 2H), 2.88-2.73 (m, 4H), 2.58-2.47 (m, 4H), 1.95 (s, 6H), 1.87 (s, 2H), 1.72-1.61 (m, 4H), 1.49 (s, 6H), 1.19-1.12 (m, 148H), 0.76-0.75 (m, 36H). HRMS (MALDI) m / z theoretical value: 2303.7523; experimental value: 2303.7389 [M+H] + .

[0081] Synthesis of the multi-resonance non-fullerene acceptor material sym-ICINBN-NS-2: Compound C-3 (46 mg, 0.02 mmol), 5,6-difluoro-3-(dicyanomethylene)indophenone (18 mg, 0.08 mmol) were weighed, and the mixture was purged three times under argon protection. 2 mL of toluene was added, followed by acetic anhydride (0.02 mg, 0.0002 mmol) and boron trifluoride diethyl ether complex (0.03 mg, 0.0002 mmol). The mixture was heated and stirred at 30 °C for 6 h. After the reaction was complete, the mixture was washed with water, extracted with dichloromethane, and the organic layers were combined and dried with anhydrous magnesium sulfate. The mixture was filtered, concentrated under reduced pressure, and then separated by column chromatography to obtain the target compound as a purple solid (22 mg, yield: 40%). 1 H NMR (400 MHz, C6D6, 297 K, ppm) δ 9.13 (s, 2H), 8.95-8.88 (m,2H), 8.56-8.49 (m, 4H), 8.36-8.32 (m, 2H), 8.18-8.16 (m, 2H), 8.14-8.11 (m,2H), 7.30-7.27 (t, J = 8.0 Hz, 2H), 6.91-6.89 (m, 4H), 5.13-5.03 (m, 2H), 4.47-4.34 (m, 2H), 3.23-3.13 (m, 4H), 2.79-2.75 (m, 4H), 2.24-2.11 (m, 4H), 2.00 (s, 6H), 1.86-1.82 (m, 2H), 1.67 (s, 6H), 1.40-1.30 (m, 148H), 0.95-0.92 (m, 36H). HRMS (MALDI) m / z theoretical value: 2727.7897; experimental value: 2725.7865 [M+H] + .

[0082] Example 4:

[0083]

[0084] Synthesis of compound B-2: Compound A (320 mg, 0.15 mmol), 4-methoxyvinyl-5-bromo-2-thiophenecarboxaldehyde (185 mg, 0.75 mmol), bis(triphenylphosphine)palladium dichloride (35 mmol, 0.05 mmol), and potassium carbonate (166 mg, 1.20 mmol) were weighed. The mixture was purged three times under argon protection. Toluene and water (volume ratio of toluene to water was 5:1) were added. The mixture was stirred and refluxed at 80 °C for 12 h. After the reaction was complete, the mixture was extracted with dichloromethane. The organic layers were combined, dried with anhydrous magnesium sulfate, filtered, concentrated under reduced pressure, and separated by column chromatography to obtain a dark green solid intermediate B-2 (196 mg, yield: 60%). 1 H NMR (400MHz, C6D6, 297 K, ppm) δ 9.82 (s, 2H), 9.57 (s, 2H), 9.29 (s, 2H), 8.55 (s, 2H), 8.41 (s, 2H), 8.17 (s, 2H), 8.00 (s, 2H), 6.82-6.80 (d, J = 8.0 Hz, 2H), 6.64-6.62 (d J = 8.0 Hz, 2H), 6.02-6.01(d, J = 4.0 Hz, 2H), 5.97-5.96 (d, J = 4.0 Hz, 2H), 3.39 (s, 6H), 3.13-3.11 (m, 4H), 2.63-2.61 (m, 4H), 2.14-2.11 (m, 2H), 1.95 (s, 6H), 1.70 (s, 2H), 1.51 (s, 6H), 1.34-1.25 (m, 128H), 0.90-0.85 (m, 24H). HRMS (MALDI) m / z theoretical value: 2165.5437; experimental value: 2164.5445 [M+H] + .

[0085] Synthesis of compound C-4: Compound B-2 (480 mg, 0.22 mmol) and bismuth trifluoromethanesulfonate (13 mg, 0.02 mmol) were weighed, the mixture was purged three times, and 10 mL of dichloroethane was added under argon protection. The mixture was stirred at room temperature for 10 h. After the reaction was completed, the mixture was concentrated under reduced pressure and then separated by column chromatography to obtain the green oily compound C-4. 1 H NMR (400 MHz, C6D6, 297 K, ppm) δ9.85 (s, 2H), 9.52 (s, 2H), 9.11 (s, 2H), 8.74 (s, 2H), 8.43 (s, 2H),8.13 (s, 2H), 7.95 (s, 2H), 7.50 (s, 2H), 6.59-6.57 (m, 4H), 3.03 (s 4H), 2.77 (s, 4H), 2.15 (s, 2H), 1.95 (s, 6H), 1.84 (s, 2H), 1.48 (s, 6H), 1.41-1.21 (m, 128H), 0.93-0.86 (m, 24H). HRMS (MALDI) m / z theoretical value: 2101.5112 ; Experimental value: 2100.5097 [M+H] + .

[0086] Synthesis of the multi-resonance non-fullerene acceptor material sym-ICINBN-PhS: Compound C-4 (42 mg, 0.02 mmol), 5,6-difluoro-3-(dicyanomethylene)indophenone (18 mg, 0.08 mmol) were weighed, and the mixture was purged three times under argon protection. 2 mL of toluene was added, followed by acetic anhydride (0.02 mg, 0.0002 mmol) and boron trifluoride diethyl ether complex (0.03 mg, 0.0002 mmol). The mixture was heated and stirred at 30 °C for 6 h. After the reaction was complete, the mixture was washed with water, extracted with dichloromethane, and the organic layers were combined and dried over anhydrous magnesium sulfate. The mixture was filtered, concentrated under reduced pressure, and then separated by column chromatography to obtain the target compound as a purple solid (20 mg, yield: 40%). HRMS (MALDI) m / z theoretical value: 2525.5487; experimental value: 2525.5468 [M+H] + .

[0087] The preparation of other structures of multiple resonance nonfullerene acceptor derivatives simply requires replacing the substituent groups of the reaction raw materials with the corresponding groups, which will not be elaborated here.

[0088] To further investigate the photoelectric properties of this type of compound, the multi-resonance non-fullerene acceptor material was characterized by UV-Vis absorption spectroscopy, fluorescence emission spectroscopy, transient emission spectroscopy, and cyclic voltammetric electrochemical characterization.

[0089] The compound sym-ICINBN-NS was formulated into 10 -5 A dilute toluene solution of mol / L was tested for its absorption spectrum at 25 °C using a UV-Vis absorption spectrometer. Figure 1As shown, the compound sym-ICINBN-NS has absorption peaks at 580 / 679 nm, with a corresponding molar absorptivity of 7.70 × 10⁻⁶. 4 / 6.00×10 4 M -1 cm -1 The maximum absorption edge is located at 805 nm, and the optical band gap is 1.54 eV. Using the same solution as described above, its photoluminescence spectrum was measured using a fluorescence spectrometer at 25 °C. Figure 2 As shown, the compound has a maximum emission wavelength of 859 nm, located in the near-infrared region. Simultaneously, the transient emission spectrum of this compound in oxygen-free toluene was measured using a transient emission spectrometer, as shown below. Figure 3 As shown, its delayed fluorescence lifetime is 5.2 μs. Finally, cyclic voltammetry curves were tested at 25 °C using an electrochemical workstation, as shown below. Figure 4 As shown, its highest occupied molecular orbital energy level is -4.91 eV, its lowest unoccupied molecular orbital is -3.61 eV, and its electrochemical bandgap is 1.30 eV. These results indicate that this type of compound is a novel non-fullerene acceptor material with excellent properties and broad application prospects in the field of organic photovoltaics.

[0090] Using the same method, the compound asym-ICINBN-NS was tested at 10 -5 Photoluminescence spectrum of a dilute toluene solution (mol / L). Figures 5-8 As shown, the compound asym-ICINBN-NS has absorption peaks at 582 / 747 nm, with a corresponding molar absorptivity of 6.01 × 10⁻⁶. 4 / 5.93×10 4 M -1 cm -1 It has a maximum absorption edge at 812 nm, an optical band gap of 1.53 eV, a maximum emission wavelength of 747 nm, a delayed fluorescence lifetime of 5.9 μs, a highest occupied molecular orbital energy level of -4.92 eV, a lowest unoccupied molecular orbital energy level of -3.62 eV, and an electrochemical band gap of 1.30 eV.

[0091] The experimental data above show that the novel multi-resonance non-fullerene acceptor material and its derivatives provided by this invention are excellent acceptor materials. These compounds have high molar absorptivity, long exciton lifetime and low frontier molecular orbital energy levels in the near-infrared region. Therefore, these multi-resonance non-fullerene acceptor materials and their derivatives have broad application prospects in the field of organic photovoltaics and can be applied to organic solar cells.

[0092] The present invention has been illustrated through the above embodiments, but the present invention is not limited to the above process steps, that is, it does not mean that the present invention must rely on the above process steps to be implemented. Those skilled in the art should understand that any improvements to the present invention, equivalent substitutions of the raw materials used in the present invention, additions of auxiliary components, and selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. A multi-resonance non-fullerene acceptor material having the structures shown in General Formula I and General Formula II as follows: in, R 1 ~R 8 Selected from hydrogen, deuterium, C1~C30 chain alkyl, C3~C30 cycloalkyl, C1~C10 alkoxy, and C1~C10 thioalkyl; Ar 1 ~Ar 2 Selected from one of C6-C30 aryl groups and C3-C30 heteroaryl groups; When Ar has substituents, they are independently selected from one of the following: deuterium, halogen, hydroxyl, carboxyl, cyano, nitro, trifluoromethyl, alkynyl, C1-C30 chain alkyl, C3-C30 cycloalkyl, C1-C10 alkoxy, C6-C30 acyl, C6-C30 arylamino, C3-C30 heteroarylamino, C6-C30 aryl, and C3-C30 heteroaryl.

2. The multiple resonance non-fullerene acceptor material according to claim 1, characterized in that, It has the structure shown in general formulas III and IV as follows: 。 3. The multiple resonance non-fullerene acceptor material according to claim 2, characterized in that, The multiple resonance non-fullerene acceptor material is selected from compounds with the following specific structures: 。 4. The method for preparing the multiple resonance non-fullerene acceptor material according to any one of claims 1 to 3, characterized in that, The preparation methods of the compounds of formula I and formula II include the following steps: (1) Reactant A, thiophene monomer, is dissolved in a solvent and reacted in the presence of a transition metal catalyst, a base, an additive, and a solvent to obtain intermediate B. The reaction formula is as follows: (2) Intermediate B was dissolved in a solvent and reacted in the presence of additives and solvent to obtain intermediates C-1 and C-2, which were then separated by column chromatography. The reaction formula is as follows: (3) Dissolve intermediate C-1 or intermediate C-2 in a solvent and react in the presence of anhydride and Lewis acid to obtain multiple resonance nonfullerene receptor I and receptor II, as shown in the following reaction formula: 。 5. The preparation method according to claim 4, characterized in that, Steps (1), (2) and (3) are all carried out in a protective atmosphere, which is nitrogen or argon.

6. The preparation method according to claim 4, characterized in that, The transition metal catalyst for the reaction in step (1) is selected from one or more of palladium acetate, palladium chloride, tetra(triphenylphosphine)palladium, bis(triphenylphosphine)palladium dichloride, 1,1'-bis(diphenylphosphine)ferrocene palladium dichloride or tri(dibenzylideneacetone)palladium. The additives used in step (1) are selected from one or more of the following: triphenylphosphine, tricyclohexylphosphine, tri-tert-butylphosphine, tris(o-methylphenyl)phosphine, 2-dicyclohexylphosphine-2',6'-dimethoxybiphenyl, 4,5-bisdiphenylphosphine-9,9-dimethyloxanthracene, 2-dicyclohexylphosphine-2',4',6'-triisopropylbiphenyl, 2-dicyclohexylphosphine-2',6'-diisopropoxy-1,1'-biphenyl, and 1,1'-bis(diphenylphosphine)ferrocene. The base used in the reaction in step (1) is selected from one or more of sodium tert-butoxide, potassium tert-butoxide, sodium carbonate, sodium bicarbonate, potassium carbonate, potassium phosphate, cesium carbonate, potassium acetate, and triethylamine. The solvent for the reaction in step (1) is selected from one or at least two of 1,4-dioxane, toluene, benzene, xylene, mesitylene or N,N-dimethylformamide, and a combination of water.

7. The preparation method according to claim 4, characterized in that, In step (1), the molar ratio of reactant A to thiophene monomer is 1.0:4.0~6.0; the reaction temperature is 70~180 ℃, and the reaction time is 8~72 h.

8. The preparation method according to claim 4, characterized in that, The reaction additives in step (2) are selected from one or more of the following: triphenylphosphine, tributylphosphine, trimethyl phosphite, triethyl phosphite, tris(diethylamino)phosphine, bismuth trifluoromethanesulfonate, and methanesulfonic acid. The solvent for the reaction in step (2) is selected from one or more of toluene, xylene, mesitylene, o-dichlorobenzene, diphenyl ether, dichloromethane, and dichloroethane; In step (2), the molar ratio of reaction intermediate B to additive is 1.0:0.1~20.0; the reaction temperature is 0~200 ℃, and the reaction time is 6~72 h.

9. The preparation method according to claim 4, characterized in that, The acid used in the reaction in step (3) is selected from one or more of boron trifluoride diethyl ether complex, β-alanine, and aluminum chloride; The dehydrating agent in step (3) is selected from one or more of acetic anhydride, propionic anhydride, trifluoroacetic anhydride, and phthalic anhydride; The solvent for the reaction in step (3) is selected from one or more of benzene, toluene, xylene, ethanol, methanol, and acetonitrile; In step (3), the molar ratio of intermediate C-1 or intermediate C-2 to IC derivative is 1.0:4.0~6.0; the reaction temperature is 20-50 ℃ and the reaction time is 3~12 h.

10. The application of the multi-resonance non-fullerene acceptor material according to any one of claims 1-3 as a photoactive layer or electron transport layer material in organic optoelectronic devices.

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