Non-conjugated connection receptor-receptor type pyrene diimide polymer, preparation method thereof, cathode interface material and semiconductor device

Abstract

The invention relates to the technical field of cathode interface materials, in particular to a non-conjugated connection receptor-receptor type pyrene diimide polymer, a preparation method thereof, a cathode interface material and a semiconductor device. The non-conjugated connection acceptor-acceptor type pyrene diimide polymer comprises a pyrene diimide unit and a conjugated acceptor unit which is in non-conjugated polymerization with pyrene diimide, wherein the conjugated acceptor unit is selected from the pyrene diimide unit or other electron-deficient acceptor units; and the ultraviolet visible light absorption range of other electron-deficient acceptor units is 250nm to 650nm. When being used as a cathode interface material, the non-conjugated connection receptor-receptor pyrene diimide polymer not only has a relatively low LUMO energy level, but also enlarges the ultraviolet visible light absorption range, further widens the light absorption range of a solar cell device, and further improves the short-circuit current density of the solar cell device.

Description

Technical Field

[0001] The present invention relates to the technical field of cathode interface materials, and in particular to a non-conjugated receptor-receptor type pyrene diimide polymer and a preparation method thereof, a cathode interface material and a semiconductor device. Background Art

[0002] Organic solar cells (OSCs) are one of the effective ways to solve environmental pollution and energy crises, and are a new generation of green energy technology with great industrial prospects. Organic solar cells are usually composed of an anode, an anode interface layer, an active layer, a cathode interface layer, and a cathode. Among them, the cathode interface layer, as an important component of organic solar cells, plays an important role in reducing the contact barrier between the active layer and the cathode, regulating the light field distribution, and enhancing the stability of the device. Therefore, the development of high-performance cathode interfacial materials (CIMs) is a key step in promoting the practical application of organic solar cells.

[0003] Currently, common cathode interface materials can form good contact between the active layer and the electrode and effectively reduce the electrode work function. However, most of them still have the problem that the LUMO energy level is higher than the LUMO energy level (≈-4.0eV) of the high-efficiency narrow-bandgap active layer acceptor materials (such as Y6 and its derivatives). This makes the cathode interface material have certain obstacles when the auxiliary electrode extracts electrons and limits its thick film preparation. At the same time, most cathode interface materials also have the problem of weak absorption or too much overlap between the absorption range and the active layer, making it difficult for the interface material to play a role in broadening the light absorption range of solar cell devices and thus improving the short-circuit current density of the device. Therefore, it is very important to develop cathode interface materials with lower LUMO energy levels and complementary to the common active layer light absorption.

[0004] In view of this, the present invention is proposed. Summary of the invention

[0005] The object of the present invention is to provide a non-conjugated receptor-receptor type pyrene diimide polymer and a preparation method thereof, a cathode interface material and a semiconductor device. The non-conjugated receptor-receptor type pyrene diimide polymer provided by the embodiment of the present invention not only has a lower LUMO energy level when used as a cathode interface material, but also increases the ultraviolet light absorption range, thereby broadening the light absorption range of the solar cell device, thereby improving the short-circuit current density of the solar cell device.

[0006] The present invention is achieved in that:

[0007] In the first aspect, the present invention provides a non-conjugated linked receptor-receptor type pyrene diimide polymer, which includes a pyrene diimide unit and a conjugated receptor unit non-conjugated with the pyrene diimide, wherein the conjugated receptor unit is selected from the pyrene diimide unit or other electron-deficient receptor units; the ultraviolet light absorption range of the other electron-deficient receptor units is 250nm-650nm.

[0008] In a second aspect, the present invention provides a method for preparing the non-conjugated linked receptor-receptor type pyrene diimide polymer described in the aforementioned embodiment, comprising non-conjugated polymerization of pyrene diimide units and conjugated receptor units.

[0009] In a third aspect, the present invention provides a cathode interface material, which includes the non-conjugated linked receptor-receptor type pyrene diimide polymer described in the aforementioned embodiment.

[0010] In a fourth aspect, the present invention provides a semiconductor device, which is prepared by the cathode interface material described in the aforementioned embodiment.

[0011] The present invention has the following beneficial effects: An embodiment of the present invention provides a new non-conjugated connected receptor-receptor type pyrene diimide polymer, which is formed by non-conjugated polymerization of pyrene diimide units and conjugated receptor units, thereby making the formed cathode interface material have a lower LUMO energy level, and the non-conjugated connection is beneficial to maximally retaining the absorption range of the pyrene diimide unit and the conjugated receptor unit, thereby broadening the light absorption range of the solar cell device and further improving the short-circuit current density of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0013] Figure 1 A spectrum showing the tested molecular weight of the non-conjugated receptor-receptor type pyrene diimide polymer provided in Example 1 of the present invention;

[0014] Figure 2 The spectrum of the tested molecular weight of the non-conjugated receptor-receptor type pyrene diimide polymer provided in Examples 2-4 of the present invention;

[0015] Figure 3 The test result diagram provided for the test example 1 of the present invention;

[0016] Figure 4 The test result diagram provided for Test Example 2 of the present invention;

[0017] Figure 5 The test result diagram provided for test example 3 of the present invention;

[0018] Figure 6 The test result diagram provided for Test Example 4 of the present invention;

[0019] Figure 7 The test result diagram provided for Test Example 5 of the present invention;

[0020] Figure 8 This is a test result diagram provided for Test Example 6 of the present invention. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical scheme and advantages of the embodiments of the present invention clearer, the technical scheme in the embodiments of the present invention will be described clearly and completely below. If the specific conditions are not specified in the embodiments, they are carried out according to conventional conditions or conditions recommended by the manufacturer. If the manufacturer of the reagents or instruments used is not specified, they are all conventional products that can be purchased commercially.

[0022] In the first aspect, an embodiment of the present invention provides a non-conjugated linked receptor-receptor type pyrene diimide polymer, which includes a pyrene diimide unit and a conjugated receptor unit non-conjugated with the pyrene diimide, wherein the conjugated receptor unit is selected from a pyrene diimide unit or other electron-deficient receptor units; wherein the ultraviolet light absorption range of the other electron-deficient receptor units is 250nm-650nm, for example, 250nm-350nm, 500nm-650nm, 450nm-600nm and 250nm-400nm.

[0023] The embodiment of the present invention adopts the pyrene diimide unit as the basic structure, realizes a non-conjugated polymer with itself or another unit with a close ultraviolet light absorption range, and constructs a series of non-conjugated connection type AA type polymer cathode interface materials. The polymer cathode interface material has a low LUMO energy level and retains the absorption range of the pyrene diimide unit and the conjugated acceptor unit, thereby broadening the light absorption range of the solar cell device and further improving the short-circuit current density of the device.

[0024] Furthermore, the non-conjugated receptor-receptor type pyrene diimide polymer is selected from the compounds represented by the following structural formula:

[0025]

[0026] Wherein, A is selected from any one of the groups shown in the following structural formulas:

[0027]

[0028]

[0029] For example, preferably

[0030] R1 is selected from any one of halogen, hydroxyl, hydrogen, substituted or unsubstituted alkyl, substituted or unsubstituted aryl, substituted or unsubstituted alkoxy, substituted or unsubstituted cycloalkyl, substituted or unsubstituted heterocyclyl, and substituted or unsubstituted alkyleneoxyalkyl; preferably, R1 is selected from any one of halogen, hydroxyl, hydrogen, substituted or unsubstituted C1-C40 straight-chain alkyl, substituted or unsubstituted C1-C40 branched alkyl, substituted or unsubstituted C5-C40 aryl, substituted or unsubstituted C1-C40 alkoxy, substituted or unsubstituted C3-C40 cycloalkyl, substituted or unsubstituted C2-C40 heterocyclyl, and substituted or unsubstituted C2-C40 alkyleneoxyalkyl; for example, R1 is selected from halogen, hydroxyl, hydrogen, and tert-butyl; more preferably tert-butyl.

[0031] R2 to R18 are each independently selected from any one of hydrogen, substituted or unsubstituted alkyl, substituted or unsubstituted aryl, substituted or unsubstituted alkoxy, substituted or unsubstituted cycloalkyl, substituted or unsubstituted heterocyclyl, and substituted or unsubstituted alkyleneoxyalkyl; R2 to R18 are each independently selected from any one of hydrogen, substituted or unsubstituted C1-C40 straight chain alkyl, substituted or unsubstituted C1-C40 branched alkyl, substituted or unsubstituted C5-C40 aryl, substituted or unsubstituted C1-C40 alkoxy, substituted or unsubstituted C3-C40 cycloalkyl, substituted or unsubstituted C2-C40 heterocyclyl, and substituted or unsubstituted C2-C40 alkyleneoxyalkyl; for example, R2 to R18 are each independently selected from hydrogen or C1-C5 unsubstituted straight chain alkyl; and n-propyl is most preferred.

[0032] It should be noted that R2, R3, R4, R5, R6, R7, R8, R9, R10, R11, R12, R13, R14, R15, R16, R17 and R18 may have the same or different substituents.

[0033] X is selected from any one of halogen, hydroxyl, carboxylate, sulfonate, hydrogen sulfide, borate ion and imide ion; for example, X is selected from any one of F, Cl, Br, I, CHCOO, OTf, OH, HSO4, BF4 and Tf2N; preferably, X represents any one of F, Cl, Br and I.

[0034] X1 to X11 are each independently selected from halogen or cyano; X12 to X23 are each independently selected from any one or more of O, S and NH; Y is selected from any one of amine, phosphine, phosphorus-containing heterocycle and nitrogen-containing heterocycle.

[0035] x and y can be in any ratio. For example, x and y can be any value between 1 and 10, more preferably, any value between 1 and 5.

[0036] Specifically, the non-conjugated receptor-receptor type pyrene diimide polymer is selected from any one of the compounds represented by the following structural formulas:

[0037]

[0038]

[0039] Wherein, n represents any value between 10-30, x represents any value between 1-10, preferably any value between 1-3; y represents any value between 1-10, preferably any value between 1-3.

[0040] It should be noted that the substituted or unsubstituted C1-C40 straight-chain alkyl group may be selected from methyl, ethyl, n-propyl, and may also be selected from n-butyl, n-pentyl, and n-hexyl. The substituted or unsubstituted C1-C40 branched-chain alkyl group may be selected from isopropyl, isobutyl, tert-butyl, and may also be selected from isopentyl, tert-pentyl, and may other branched-chain alkyl groups. The substituted or unsubstituted C5-C40 aromatic group may be selected from phenyl, thiophene, imidazole, biphenyl, terphenyl, naphthyl, phenanthryl, triphenylene, fluorenyl, pyridinyl, pyrimidinyl, pyridazinyl, quinolyl, pyrazinyl, isoquinolinyl, quinoxalinyl, quinazolinyl, cinnolinyl, triazine, naphthyridinyl, pyridinopyrazinyl, thienyl, benzothienyl, dibenzothienyl, furanyl, benzofuranyl, dibenzofuranyl, azadibenzofuranyl, azadibenzothienyl, 9,9-dimethylfluorenyl, carbazolyl, aromatic amine and the like. The substituted or unsubstituted C1-C40 alkoxy group may be selected from methoxy, ethoxy, propoxy, isopropoxy, n-butoxy, sec-butoxy, isobutoxy, tert-butoxy, pentyloxy, hexyloxy, heptyloxy, octyloxy, nonyloxy, decyloxy, undecyloxy, dodecyloxy, tridecyloxy, tetradecyloxy, pentadecyloxy, hexadecyloxy, heptadecanyloxy, octadecyloxy, octadecyloxy, octadecyloxy, octadecyloxy, nonadecanyloxy, etc. The substituted or unsubstituted C3-C40 cycloalkyl group may be selected from cyclopropyl, cyclobutyl, cyclopentyl, cyclopentenyl, cyclohexyl, cyclohexenyl, cyclohexadienyl, etc. The cycloalkyl groups may be selected from cycloheptyl, cycloheptatrienyl, cyclooctyl, etc. The substituted or unsubstituted C2-C40 heterocyclic group can be selected from pyrrolidinyl, azetidinyl, oxetanyl, pyrazolinyl, imidazolidinyl, imidazolinyl, oxazolidinyl, isoxazolidinyl, thiazolidinyl, isothiazolidinyl, tetrahydrofuranyl, piperazinyl, piperidinyl, 2-oxopiperazinyl, 2-oxopiperidinyl, 2-oxopyrrolidinyl and hexahydroazepinyl, and can also be selected from 4-piperidone, tetrahydropyranyl, 1,3-dioxanyl, morpholinyl, thiomorpholinyl, thiomorpholinyl sulfoxide, thiomorpholinyl sulfone and tetrahydro-1,1-dioxythiophene and other heterocyclic groups.

[0041] The substituted or unsubstituted C2-C40 alkyleneoxyalkyl group means a group obtained by removing a hydrogen atom from a "C1C50 alkoxy group".

[0042] In a second aspect, an embodiment of the present invention provides a method for preparing a non-conjugated linked receptor-receptor type pyrene diimide polymer, comprising non-conjugated polymerization of a pyrene diimide unit and a conjugated receptor unit;

[0043] Preferably, the synthesis is carried out according to the following synthesis route:

[0044]

[0045] The method comprises: mixing x mol of compound 1, y mol of compound 2, x+y mol of compound 3 and 2(x+y)L of solvent at 50-80° C. and reacting under an inert gas atmosphere. Specifically, compound 1 (x mol), compound 2 (y mol), compound 3 (x+y mol) and 2(x+y)L of trifluoroethanol (TFE) solvent are added into a Schlenk tube. The reaction mixture is heated to 50-80° C. and stirred for 48 hours under a nitrogen atmosphere. After the reaction is cooled, it is precipitated with dichloromethane to obtain a product.

[0046] In a third aspect, an embodiment of the present invention provides a cathode interface material, which includes the non-conjugated linked receptor-receptor type pyrene diimide polymer described in the aforementioned embodiment.

[0047] In a fourth aspect, the present invention provides a semiconductor device, which is prepared by the cathode interface material described in the above embodiment. Wherein, the semiconductor device includes a photoelectric device; the photoelectric device includes any one of an electroluminescent device, a field effect transistor, a photodetector device and a solar cell device;

[0048] The solar cell device comprises an organic solar cell device; the organic solar cell device comprises a cathode interface layer, wherein the cathode interface layer is prepared by the cathode interface material mentioned above.

[0049] The features and performance of the present invention are further described in detail below in conjunction with the embodiments.

[0050] Example 1

[0051] The embodiment of the present invention provides a method for preparing a non-conjugated receptor-receptor type pyrene diimide polymer, comprising:

[0052] The synthesis was carried out according to the following synthesis route:

[0053]

[0054] Specifically, PyDIN (311 mg, 0.5 mmol), 1,3-dibromopropane (100.9 mg, 0.5 mmol) and 2 mL of trifluoroethanol (TFE) solvent were added to a 10 mL Schlenk tube. The reaction mixture was heated to 70 ° C and stirred for 48 h under a nitrogen atmosphere. After the reaction was cooled, it was precipitated with dichloromethane to obtain a yellow solid polymer PPyDIN-C3 (yield 90%).

[0055] The characterization spectrum of polymer PPyDIN-C3 can be found in Figure 1 The characterization data are as follows: Using hexafluoroisopropanol (HFIP) as the eluent, gel permeation chromatography (GPC) characterized the molecular weight of the yellow solid polymer: M n=8.01 kg mol -1 , M w =33.23 kg mol -1 . NMR data: 9.33-9.49 (m, 4H), 4.01-4.17 (s, 4H), 3.60-3.75 (m, 4H), 3.35-3.48 (m, 4H), 3.12-3.35 (m, 12H), 2.42-2.56 (s, 4H), 1.86-2.01 (m, 4H), 1.52-1.60 (m. 4H). It can be seen that the desired non-conjugated receptor-receptor type pyrene diimide polymer was synthesized in this embodiment.

[0056] Embodiment 2-4

[0057] The embodiments of the present invention all provide a method for preparing a non-conjugated receptor-receptor type pyrene diimide polymer, comprising:

[0058] The synthesis was carried out according to the following synthesis route:

[0059]

[0060] PyDIN (x mmol), NDIN (y mmol) (x+y=0.5mmol), 1,3-dibromopropane (100.9mg, 0.5mmol) and 2mL of trifluoroethanol (TFE) solvent were added to a 10mL Schlenk tube. The reaction mixture was heated to 70°C and stirred for 48h under a nitrogen atmosphere. After the reaction was cooled, it was precipitated with dichloromethane to obtain a yellow solid polymer (yield 93%).

[0061] Example 2: When x / y=3 / 1, the yellow solid polymer is recorded as PPyN31. The molecular weight of the yellow solid polymer is characterized by gel permeation chromatography (GPC) using hexafluoroisopropanol (HFIP) as the eluent: M n =13.48 kg mol -1 ,M w =35.91kgmol -1 .

[0062] Example 3: When x / y=1 / 1, the yellow solid polymer is recorded as PPyN11. The molecular weight of the yellow solid polymer is characterized by gel permeation chromatography (GPC) using hexafluoroisopropanol (HFIP) as the eluent: M n =21.33 kg mol -1 ,M w =59.19 kgmol -1 .

[0063] Example 4: When x / y=1 / 3, the yellow solid polymer is recorded as PPyN13. The molecular weight of the yellow solid polymer is characterized by gel permeation chromatography (GPC) using hexafluoroisopropanol (HFIP) as the eluent: M n =37.85 kg mol -1 ,M w =114.46 kg mol -1 .

[0064] The molecular weight spectrum of the non-conjugated receptor-receptor type pyrene diimide polymer of Example 2-4 is shown in Figure 2 .

[0065] Example 5

[0066] The embodiment of the present invention provides a method for preparing a non-conjugated receptor-receptor type pyrene diimide polymer, comprising:

[0067] The synthesis was carried out according to the following synthesis route:

[0068]

[0069] t-PyDIN (0.25 mmol), BTN (0.25 mmol), 1,3-dibromopropane (100.9 mg, 0.5 mmol) and 2 mL of trifluoroethanol (TFE) solvent were added to a 10 mL Schlenk tube. The reaction mixture was heated to 70 ° C and stirred for 48 h under a nitrogen atmosphere. After the reaction was cooled, it was precipitated with dichloromethane to obtain an orange-yellow solid polymer PPyB11 (yield 90%).

[0070] Example 6

[0071] The embodiment of the present invention provides a method for preparing a non-conjugated receptor-receptor type pyrene diimide polymer, comprising:

[0072] The synthesis was carried out according to the following synthesis route:

[0073]

[0074] Specifically, t-PyDIN (311 mg, 0.5 mmol), 2,2'-dibromodiethyl ether (116 mg, 0.5 mmol) and 2 mL of trifluoroethanol (TFE) solvent were added to a 10 mL Schlenk tube. The reaction mixture was heated to 70 ° C and stirred for 48 h under a nitrogen atmosphere. After the reaction was cooled, it was precipitated with dichloromethane to obtain a yellow solid polymer PPyDIN-O (yield 93%).

[0075] Test Example 1

[0076] The t-PyDIN and PPyDIN-C3 of Example 1 were tested. Figure 3 and Table 1.

[0077] Figure 3 a is the UV-visible absorption spectra of t-PyDIN and PPyDIN-C3; Figure 3 b is the cyclic voltammetry curves of t-PyDIN and PPyDIN-C3; Figure 3 (c) is the energy level diagram of t-PyDIN and PPyDIN-C3; Figure 3 (d) is the electron paramagnetic resonance image of t-PyDIN and PPyDIN-C3; Figure 3 e in the figure is the UV photoelectron spectrum of t-PyDIN; Figure 3 f in the figure is the UV photoelectron spectrum of Ag and PPyDIN-C3.

[0078] Table 1 Optical and electrochemical analysis data of t-PyDIN and PPyDIN-C3

[0079]

[0080] According to Table 1 and Figure 3 It can be seen that (1) the main light absorption range of t-PyDIN is 350nm-500nm, which can form a good complementary absorption with the current high-performance active layer materials. The LUMO energy level of t-PyDIN is -3.57eV. The embodiment of the present invention adopts the Menshutkin reaction to react t-PyDIN and 1,3-dibromopropane to obtain PPyDIN-C3 polymer. According to Figure 3 As shown in (a), PPyDIN-C3 absorbs in the range of approximately 280 to 320 nm and 350 to 500 nm, indicating that this non-conjugated link retains the unique absorption range of the small molecule t-PyDIN, and PPyDIN-C3 has the characteristic of complementary light absorption with current high-performance active layer materials.

[0081] (2) Based on Figure 3 As shown in Figure c, the LUMO energy level of PPyDIN-C3 is -3.75eV. Compared with the LUMO energy level of the small molecule t-PyDIN (-3.57eV), the LUMO energy level of the PPyDIN-C3 polymer has decreased, which shows that the receptor-receptor non-conjugated polymerization method can significantly reduce the LUMO energy level of the molecule. The lower LUMO energy level of PPyDIN-C3 is more conducive to the transmission and extraction of electrons, and is conducive to the preparation of thickness-insensitive cathode interface layers.

[0082] (3) Based on Figure 3It can be seen from the electron paramagnetic resonance (EPR) diagram that the PPyDIN-C3 cathode interface material shows a paramagnetic signal centered at 3510G, which indicates that PPyDIN-C3 has a self-doping property. This self-doping effect promotes the formation of an interface dipole between the active layer and the electrode, which can effectively reduce the work function of the electrode and promote electron transport in photovoltaic devices. Figure 3 From the graphs e and f, we can see that the work function of the silver (Ag) electrode modified by t-PyDIN decreases from 4.64eV to 4.10eV, and the work function of the silver (Ag) electrode modified by PPyDIN-C3 decreases from 4.64eV to 3.92eV. The PPyDIN-C3 polymer is an organic cationic electrolyte material with cations in the main chain and free anions. The interfacial dipole formed can significantly reduce the work function of Ag. This is conducive to the formation of ohmic contact at the metal / organic semiconductor interface and the enhancement of the built-in electric field, which is conducive to the generation and extraction of free charges in the device.

[0083] Test Example 2

[0084] The photovoltaic performance of organic solar cell devices based on t-PyDIN or PPyDIN-C3 cathode interface materials was studied using the forward device structure of ITO / PEDOT:PSS / active layer / CIL / Ag. Wide-bandgap polymer donor PBDB-T-2F and narrow-bandgap small molecule acceptor Y6 were selected as photoactive layer materials, and t-PyDIN or PPyDIN-C3 was used as cathode interface material, respectively. At the same time, photovoltaic devices without cathode interface layer were prepared as control groups.

[0085] The preparation process of the device is as follows: (1) The indium tin oxide (ITO) glass substrate is scrubbed with a dilute detergent solution and ethanol in turn, and then ultrasonically cleaned with deionized water, acetone, and isopropanol for 20 minutes in turn, and the ITO glass substrate is blown dry with a high-purity nitrogen gun before use. After that, it is placed in a UV-ozone cleaner for 20 minutes. (2) Preparation of the hole transport layer: Under room temperature conditions, the hole transport layer PEDOT:PSS (Clevios PVP AI 4083) aqueous solution is filtered with a 0.45μm water filter membrane, spread on the surface of the ITO substrate, and spin-coated at a speed of 4800rpm for 20s to obtain ITO / PEDOT:PSS. Finally, ITO / PEDOT:PSS is annealed on a heating table at 150°C for 15 minutes and then transferred to a glove box with a nitrogen atmosphere to prepare an active layer. (3) Preparation of active layer: For the binary system with PBDB-T-2F:Y6 as the active layer, the total concentration of the active layer blend solution of this binary system was 13.2 mg mL -1, prepare the solution according to the donor-acceptor mass ratio of 1:1.2. For the preparation of the active layer solution: the solvent is chloroform obtained by redistillation, and the additive is 1-chloronaphthalene, which accounts for 0.5% of the total volume. The active layer solution is stirred at room temperature in a glove box with a nitrogen atmosphere for 6 hours. On the surface of the ITO / PEDOT:PSS substrate, the spin coating speed is 3000rpm, and the time is 30s. After the active layer film is prepared, the spin-coated film is placed on a 110℃ constant temperature heating table for thermal annealing, and the annealing time is 10 minutes. (4) Preparation of the cathode interface layer: Prepare cathode interface layer solutions of different concentrations, and the solvent used for the cathode interface material is trifluoroethanol. The solution is stirred at room temperature for several minutes until the cathode interface material is completely dissolved, and then filtered with an organic filter membrane, and the cathode interface layer is spin-coated on the active layer film at a spin coating speed of 3000rpm. (5) Evaporation of silver (Ag) electrode: The metal electrode Ag was prepared by vacuum evaporation. 60 nm of silver was evaporated in a vacuum evaporation box as the cathode of the battery. The effective area of ​​the device finally prepared was 4 mm 2 .

[0086] The JV curve, EQE curve of the tested device and the JV curve of the device with PPyDIN-C3 cathode interface layer at different film thicknesses.

[0087] Results Figure 4 , Table 2 and Table 3, where Figure 4 a in the figure shows the JV curve of the optimal device based on the t-PyDIN cathode interface layer. Figure 4 b shows the JV curve of the optimal device based on the PPyDIN-C3 cathode interface layer. Figure 4 c in the figure shows the EQE curve of the optimal device based on the PPyDIN-C3 cathode interface layer. Figure 4 Figure d shows the JV curves of devices based on t-PyDIN cathode interface layers with different film thicknesses. Figure 4 (e) shows the JV curves of devices based on PPyDIN-C3 cathode interface layers with different film thicknesses.

[0088] Table 2 at 1000W m -2 Optimal device parameters based on different cathode interface materials with PBDB-T-2F:Y6 as active layer under AM 1.5G simulated sunlight

[0089]

[0090] Table 3 at 1000W m -2 Device parameters based on PPyDIN-C3 cathode interface layer with different film thicknesses using PBDB-T-2F:Y6 as active layer under AM 1.5G simulated sunlight irradiation

[0091]

[0092] according to Figure 4 From Table 2, we can see that the device using PPyDIN-C3 as the cathode interface layer exhibits a high energy conversion efficiency of 16.85%, while the efficiency of the device without the cathode interface layer is only 11.62%. Figure 4 From a and Table 2, it can be seen that the photoelectric conversion efficiency of the device with raw material t-PyDIN as the cathode interface layer is 16.44%. The organic photovoltaic device with PPyDIN-C3 as the cathode interface layer is significantly higher than the device without the cathode interface layer and also higher than the device with raw material t-PyDIN cathode interface layer.

[0093] according to Figure 4 It can be seen from the c that the external quantum efficiency (EQE) response of the device based on PPyDIN-C3 as the cathode interface material is more than 80% in the range of 500-790nm, which proves that there is an effective charge transfer and extraction process in the device. In particular, the device with PPyDIN-C3 as the cathode interface material shows a higher EQE response in the range of 300-500nm, which can be attributed to the strong absorption properties of PPyDIN-C3 in this range. The optical complementary absorption characteristics between the active layer and the PPyDIN-C3 cathode interface material enable the device based on the PPyDIN-C3 cathode interface to have 26.70mAcm -2 The short-circuit current density is higher than that of the cathode interface layer with t-PyDIN (26.35 mA cm -2 ) and without cathode interface layer (25.50 mA cm -2 The integrated current density is consistent with the short-circuit current density obtained from the J–V curve test.

[0094] according to Figure 4 From Table 3, it can be seen that when the t-PyDIN cathode interface material is 8nm, the photoelectric conversion efficiency of the device is 16.44%. When the thickness of the t-PyDIN cathode interface material increases to 24nm, the device efficiency is only 6.66%, which is about 40% of the maximum photoelectric conversion efficiency value (16.44%). This shows that the raw material t-PyDIN cathode interface material has film thickness sensitivity and is not suitable for use at a larger film thickness.

[0095] In contrast, according to Figure 4As shown in Table 3, the PPyDIN-C3 cathode interface material shows high photoelectric conversion efficiency in a wide thickness range of 6nm to 121nm. When the thickness of the PPyDIN-C3 cathode interface material increases to 121nm, the device efficiency is 14.31%, which is about 85% of the highest photoelectric conversion efficiency value (16.85%). As shown in Table 3, with the increase of the thickness of the PPyDIN-C3 cathode interface material, the open circuit voltage (Voc) does not decrease significantly, especially at a thickness of 121nm cathode interface material, the open circuit voltage can still be maintained at 0.863V. This can be attributed to the fact that the PPyDIN-C3 cathode interface material has a lower LOMO energy level than the raw material t-PyDIN.

[0096] Test Example 3

[0097] The yellow solid polymers 3 of PPyN31, PPyN11 and PPyN13 prepared in Examples 2-4 were tested. Figure 5 and Table 4.

[0098] Figure 5 a in the figure shows the UV-visible absorption spectra of PPyN31, PPyN11 and PPyN13; Figure 5 b shows the cyclic voltammetry curves of PPyN31, PPyN11 and PPyN13; Figure 5 c represents the energy level diagram of PPyN31, PPyN11 and PPyN13; Figure 5 (d) shows the electron paramagnetic resonance images of PPyN31, PPyN11 and PPyN13; Figure 5 e in the figure represents the ultraviolet photoelectron energy spectrum of PPyN31, PPyN11 and PPyN13.

[0099] Table 4 Optical and electrochemical analysis data of PPyN31, PPyN11 and PPyN13

[0100]

[0101] according to Figure 5 As can be seen from Table 4, the embodiments of the present invention use 4,5,9,10-pyrene diimide derivative t-PyDIN and naphthalene diimide derivative NDIN to form A1-A2 type polymers through Menschuktin reaction with 1,3-dibromopropane to prepare an organic cathode interface material with a lower LUMO energy level and complementary to the current high-performance active layer light absorption, and the absorption range and energy level of the material can be precisely adjusted by adjusting the ratio of t-PyDIN and NDIN units.

[0102] according to Figure 5From a, we can see that the absorption peaks of PPyN31, PPyN11 and PPyN13 at about 310nm can be attributed to the π-π* transition of the pyrene unit, the absorption peak at about 387nm is attributed to the π-π* transition of the NDIN unit, and the adsorption peak at about 420nm should be attributed to the n-π* transition of the polar double bond in the t-PyDIN imide part. It can be seen that the receptor-receptor polymer using non-conjugated connection of t-PyDIN and NDIN retains the UV-visible absorption characteristics of monomers t-PyDIN and NDIN. The main absorption range of PPyN31, PPyN11 and PPyN13 is 275nm-500nm, which has the characteristics of complementary light absorption with the current high-performance active layer materials, which helps to broaden the light absorption range of organic solar cell devices and improve the photocurrent of the device.

[0103] according to Figure 5 As shown in Figures b and c, the energy levels of these polymer cathode interface materials were tested and calculated by electrochemical cyclic voltammetry (CV). According to the reduction potential, the lowest unoccupied molecular orbital (LUMO) energy levels of PPyN31, PPyN11, and PPyN13 are -3.76, -4.17, and -4.10 eV, respectively. The receptor-receptor type polymerization method can significantly reduce the LUMO energy level of the molecule. The LUMO energy levels of PPyN11 and PPyN13 are even lower than the LUMO energy level of high-efficiency narrow-bandgap receptor materials (such as Y6 and its derivatives) (≈-4.0 eV), which makes them have better energy level arrangement at the cathode interface and is more conducive to the transmission of electrons.

[0104] according to Figure 5 As shown in Figure d, the cathode interface materials of PPyN31, PPyN11 and PPyN13 show paramagnetic signals centered at 3510G in the electron paramagnetic resonance (EPR) diagram, which is due to the effective self-doping effect caused by the charge transfer between the strong electron-withdrawing imide group and the quaternary ammonium salt. Under the same mass, the paramagnetic signals of the cathode interface materials of PPyN31, PPyN11 and PPyN13 are successively enhanced, which is because the naphthalene diimide skeleton has stronger electron-withdrawing properties than the pyrene diimide skeleton, which is consistent with the change trend of the LUMO energy level of PPyN31, PPyN11 and PPyN13.

[0105] according to Figure 5 It can be seen from the figure that the work function of the Ag electrode modified with PPyN31, PPyN11 and PPyN13 decreased from 4.64 eV to 3.80, 3.84 and 3.94 eV, respectively. The PPyN31, PPyN11 and PPyN13 cathode interface materials significantly reduced the work function of the Ag electrode, which is beneficial to the formation of ohmic contact at the metal / organic semiconductor interface and the enhancement of the built-in electric field, which is beneficial to the generation and extraction of free charges in the device.

[0106] Test Example 4

[0107] The photovoltaic performance of organic solar cell devices based on the PPyN31, PPyN11 and PPyN13 cathode interface materials of Examples 2-4 was studied using a forward device structure of ITO / PEDOT:PSS / active layer / CIL / Ag.

[0108] The wide bandgap polymer donor PBDB-T-2F and the narrow bandgap small molecule acceptor Y6 were selected as the photoactive layer materials, and PPyN31, PPyN11 and PPyN13 were used as cathode interface materials. The device preparation method is the same as that of the device in Test Example 2.

[0109] The JV curve, EQE curve of the tested device and the JV curve of the device with PPyN31 cathode interface layer at different film thicknesses.

[0110] Results Figure 6 , Table 5 and Table 6. Figure 6 a in the figure represents the JV curve. Figure 6 b in the figure represents the EQE curve. Figure 6 (c) shows the JV curve of the device with PPyN31 cathode interface layer at different film thicknesses.

[0111] Table 5 at 1000W m -2 Optimal device parameters based on different cathode interface layers with PBDB-T-2F:Y6 as the active layer under AM 1.5G simulated sunlight.

[0112]

[0113] Table 6 at 1000W m -2 Device parameters based on PPyN31 cathode interface layer with different film thicknesses using PBDB-T-2F:Y6 as the active layer under AM 1.5G simulated sunlight.

[0114]

[0115] according to Figure 6From a and Table 5, we can see that after device optimization, the device based on PPyN31 achieved a photoelectric conversion efficiency of 17.12%, which is one of the highest photoelectric conversion efficiencies based on the PM6:Y6 binary system. At the same time, the devices using PPyN11 and PPyN13 as the cathode interface layer showed photoelectric conversion efficiencies of 16.53% and 17.06%, respectively, which are significantly higher than the efficiency of the device without a cathode interface layer (11.68%). It can be seen that the three cathode interface materials PPyN31, PPyN11 and PPyN13 play a very important role in improving the photovoltaic performance of organic solar cell devices.

[0116] according to Figure 6 As shown in Table 5, the external quantum efficiency (EQE) response of the devices based on these cathode interface materials exceeds 80% in the range of 510-790 nm, which proves that there is an effective charge transport and extraction process in the device. The light complementary absorption characteristics between the active layer and the three cathode interface materials enable the devices based on these cathode interfaces to have 25.57, 25.45 and 25.07 mA cm -2 The integrated current density is in good agreement with the short-circuit current density obtained from the J–V curve test. These results indicate that PPyN31, PPyN11, and PPyN13 can broaden the absorption range of the device and provide an efficient photoelectric conversion process.

[0117] Taking the PPyN31 polymer cathode interface material as an example, the film thickness sensitivity of the receptor-receptor type cathode interface material formed by t-PyDIN and NDIN is explored. The detailed device parameters of the cathode interface layer PPyN31 at different film thicknesses are summarized in Table 6. The results show that when the thickness of the PPyN31 cathode interface layer is 12nm, its device has a high photoelectric conversion efficiency of 17.12%. When the thickness of the PPyN31 cathode interface layer increases to 75nm, the photoelectric conversion efficiency of the device is 16.49%, maintaining more than 96% of the best device efficiency; when the thickness of the PPyN31 cathode interface layer is further increased to 86nm, the photoelectric conversion efficiency of the device is 15.58%, maintaining more than 90% of the best device efficiency.

[0118] Test Example 5

[0119] The orange-yellow solid polymer PPyB11 prepared in Example 5 was tested. Figure 7 , Table 7 and Table 8.

[0120] Figure 7 a in the middle represents the UV-visible absorption spectrum of PPyB11; Figure 7 b in the figure shows the cyclic voltammetry curve of PPyB11; Figure 7(c) shows the JV curve of the optimal device based on the PPyB11 cathode interface layer in the PBDB-T-2F:Y6 system.

[0121] Table 7 Optical and electrochemical analysis and device data of PPyB11.

[0122]

[0123] according to Figure 7 As can be seen from Table 7, the embodiments of the present invention use 4,5,9,10-pyrene diimide derivative t-PyDIN and benzothiadiazole derivative BTN to form A1-A2 type polymers through Menschuktin reaction with 1,3-dibromopropane to prepare organic cathode interface materials with lower LUMO energy level and complementary to the current high-performance active layer light absorption.

[0124] according to Figure 7 From a, we can see that the absorption peak of PPyB11 at about 304nm can be attributed to the π-π* transition of the pyrene unit and the π-π* transition of benzodithiazole, while the adsorption peak at about 423nm should be attributed to the n-π* transition of the polar double bond in the imide part of t-PyDIN and the polaron absorption of the BTN unit. It can be seen that the receptor-receptor polymer using non-conjugated connection of t-PyDIN and BTN retains the UV-visible absorption characteristics of monomers t-PyDIN and BTN. The main absorption range of PPyB11 is 280nm-500nm, which has the characteristics of complementary light absorption with the current high-performance active layer materials, which helps to broaden the light absorption range of organic solar cell devices and improve the photocurrent of the device.

[0125] according to Figure 7 As shown in Figure b, the energy level of the PPyB11 polymer cathode interface material was tested and calculated by electrochemical cyclic voltammetry (CV). According to the reduction potential, the lowest unoccupied molecular orbital (LUMO) energy level of PPyB11 is -4.15 eV. The receptor-receptor type polymerization method can significantly reduce the LUMO energy level of the molecule. The LUMO energy level of PPyB11 is lower than the LUMO energy level of efficient narrow bandgap receptor materials (such as Y6 and its derivatives) (≈-4.0 eV), which enables barrier-free electron transport and extraction at the cathode interface.

[0126] The photovoltaic performance of the organic solar cell device based on the PPyB11 cathode interface material of Example 5 was studied using a forward device structure of ITO / PEDOT:PSS / active layer / CIL / Ag.

[0127] The wide bandgap polymer donor PBDB-T-2F and the narrow bandgap small molecule acceptor Y6 were selected as the photoactive layer materials, and PPyB11 was used as the cathode interface material. The device preparation method refers to the device preparation method of detection example 2.

[0128] The JV curve of the tested device. The results are shown in Figure 7 and Table 8. Among them Figure 7 In the figure, c represents the JV curve.

[0129] Table 8 at 1000W m -2 Optimal device parameters based on PPyB11 cathode interface layer with PBDB-T-2F:Y6 as active layer under AM 1.5G simulated sunlight irradiation.

[0130]

[0131] according to Figure 7 From c and Table 8, we can see that after device optimization, the device based on PPyB11 achieved a photoelectric conversion efficiency of 16.61%, which is higher than the efficiency of the device based on the cathode interface layer without cathode (11.62%). It can be seen that the PPyB11 cathode interface material significantly improves the photoelectric conversion efficiency of organic solar cell devices, which should be attributed to the lower LUMO energy level of the acceptor-acceptor type PPyB11 cathode interface material, which promotes the extraction of electrons by the cathode and inhibits charge recombination.

[0132] Test Example 6

[0133] The yellow solid polymer PPyDIN-O prepared in Example 6 was tested. Figure 8 , Table 9 and Table 10.

[0134] Figure 8 a in the figure shows the UV-visible absorption spectrum of PPyDIN-O; Figure 8 b shows the cyclic voltammetry curve of PPyDIN-O; Figure 8 (c) shows the JV curve of the optimal device based on the PPyDIN-O cathode interface layer in the PBDB-T-2F:Y6 system.

[0135] Table 9 Optical and electrochemical analysis and device data of PPyDIN-O.

[0136]

[0137] according to Figure 8As shown in Table 9, the embodiment of the present invention uses 4,5,9,10-pyrene diimide derivative t-PyDIN to form a receptor-receptor type polymer through the Menschuktin reaction with 2,2'-dibromodiethyl ether to prepare an organic cathode interface material with a lower LUMO energy level and complementary to the current high-performance active layer light absorption.

[0138] according to Figure 8 From the a, we can see that the absorption peak of PPyDIN-O at about 304nm can be attributed to the π-π* transition of the pyrene unit and the π-π* transition of benzodithiazole, while the adsorption peak at about 425nm should be attributed to the n-π* transition of the polar double bond in the imide part of t-PyDIN. It can be seen that the PPyDIN-O polymer retains the ultraviolet-visible absorption characteristics of the monomer t-PyDIN. The main absorption range of PPyDIN-O is 275nm-466nm, which has the characteristics of complementary light absorption with the current high-performance active layer materials, which helps to broaden the light absorption range of organic solar cell devices and improve the photocurrent of the device.

[0139] according to Figure 8 As shown in Figure b, the energy level of the PPyDIN-O polymer cathode interface material was tested and calculated by electrochemical cyclic voltammetry (CV). According to the reduction potential, the lowest unoccupied molecular orbital (LUMO) energy level of PPyDIN-O is -3.77 eV. The receptor-receptor type polymerization method can obtain a cathode interface material with a lower LUMO energy level, which is beneficial to the electron extraction at the cathode interface of the device.

[0140] The photovoltaic performance of the organic solar cell device based on the PPyDIN-O cathode interface material of Example 6 was studied using a forward device structure of ITO / PEDOT:PSS / active layer / CIL / Ag.

[0141] A wide bandgap polymer donor PBDB-T-2F and a narrow bandgap small molecule acceptor Y6 were selected as the photoactive layer materials, and PPyDIN-O was used as the cathode interface material. The device preparation method is the same as that of the device in Test Example 2.

[0142] The JV curve of the tested device. The results are shown in Figure 8 and Table 10. Among them Figure 8 In the figure, c represents the JV curve.

[0143] Table 10 at 1000W m -2 Optimal device parameters based on PPyDIN-O cathode interface layer with PBDB-T-2F:Y6 as active layer under AM 1.5G simulated sunlight irradiation.

[0144]

[0145] according to Figure 8 From the c and Table 10, it can be seen that after device optimization, the device based on PPyDIN-O achieved a photoelectric conversion efficiency of 16.77%, which is higher than the efficiency of the device based on the cathode interface layer without a cathode (11.62%). It can be seen that the PPyDIN-O cathode interface material significantly improves the photoelectric conversion efficiency of the organic solar cell device, which should be attributed to the acceptor-acceptor type PPyDIN-O cathode interface material having a lower LUMO energy level and a light absorption range complementary to the active layer, which promotes the extraction of electrons by the cathode and improves the light utilization efficiency of the device.

[0146] It can be seen that the thick film efficiency retention performance of the cathode interface layer obtained by the cathode interface material provided by the embodiment of the present invention is the highest value when the film thickness of the cathode interface material exceeds 80nm. This feature is due to the fact that the cathode interface material formed by the non-conjugated receptor-receptor provided by the embodiment of the present invention has the characteristics of absorption complementarity and energy level matching with the active layer material, so even in the case of thick film, it will not affect the light absorption and charge transfer performance of the device too much. It can be seen that the non-conjugated receptor-receptor type pyrene diimide polymer provided by the embodiment of the present invention provides an efficient design strategy for large-area and thick-film electronic devices, and has huge commercial potential.

[0147] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A non-conjugated receptor-receptor type pyrene diimide polymer, characterized in that: It includes a pyrene diimide unit and a conjugated acceptor unit that is non-conjugated with the pyrene diimide, wherein the conjugated acceptor unit is selected from a pyrene diimide unit or other electron-deficient acceptor units; The ultraviolet visible light absorption range of the other electron-deficient acceptor units is 250nm-650nm.

2. The non-conjugated receptor-receptor type pyrene diimide polymer according to claim 1, characterized in that: The ultraviolet visible light absorption range of the other electron-deficient acceptor units is 250nm-350nm or 500nm-650nm.

3. The non-conjugated receptor-receptor type pyrene diimide polymer according to claim 1, characterized in that: It is selected from the compounds represented by the following structural formula: Wherein, A is selected from any one of the groups shown in the following structural formulas: R1 is selected from any one of halogen, hydroxyl, hydrogen, substituted or unsubstituted alkyl, substituted or unsubstituted aryl, substituted or unsubstituted alkoxy, substituted or unsubstituted cycloalkyl, substituted or unsubstituted heterocyclyl, substituted or unsubstituted alkyleneoxyalkyl; R2 to R18 are each independently selected from any one of hydrogen, substituted or unsubstituted alkyl, substituted or unsubstituted aryl, substituted or unsubstituted alkoxy, substituted or unsubstituted cycloalkyl, substituted or unsubstituted heterocyclyl, and substituted or unsubstituted alkyleneoxyalkyl; X is selected from any one of halogen, hydroxyl, carboxylate, sulfonate, hydrogen sulfide, borate ion and imide salt ion; X1 to X11 are each independently selected from halogen or cyano; X12 to X23 are each independently selected from any one or more of O, S and NH; Y is selected from any one of amine, phosphine, phosphorus-containing heterocycle and nitrogen-containing heterocycle; x and y can be in any ratio.

4. The non-conjugated receptor-receptor type pyrene diimide polymer according to claim 3, characterized in that: R1 is selected from any one of halogen, hydroxyl, hydrogen, substituted or unsubstituted C1-C40 straight-chain alkyl, substituted or unsubstituted C1-C40 branched alkyl, substituted or unsubstituted C5-C40 aryl, substituted or unsubstituted C1-C40 alkoxy, substituted or unsubstituted C3-C40 cycloalkyl, substituted or unsubstituted C2-C40 heterocyclyl, and substituted or unsubstituted C2-C40 alkyleneoxyalkyl; Preferably, R1 is selected from halogen, hydroxy, hydrogen, tert-butyl; more preferably tert-butyl.

5. The non-conjugated receptor-receptor type pyrene diimide polymer according to claim 3, characterized in that: R2 to R18 are each independently selected from any one of hydrogen, substituted or unsubstituted C1-C40 straight-chain alkyl, substituted or unsubstituted C1-C40 branched alkyl, substituted or unsubstituted C5-C40 aryl, substituted or unsubstituted C1-C40 alkoxy, substituted or unsubstituted C3-C40 cycloalkyl, substituted or unsubstituted C2-C40 heterocyclyl, and substituted or unsubstituted C2-C40 alkyleneoxyalkyl; Preferably, R2 to R18 are each independently selected from hydrogen or C1-C5 unsubstituted linear alkyl; most preferably n-propyl.

6. The non-conjugated receptor-receptor type pyrene diimide polymer according to claim 3, characterized in that: X is selected from any one of F, Cl, Br, I, CHCOO, OTf, OH, HSO4, BF4 and Tf2N; Preferably, X represents any one of F, Cl, Br and I; Preferably, Y represents an amine; Preferably, x is any value between 1 and 10, more preferably any value between 1 and 5. Preferably, y is any value between 1-10, more preferably any value between 1-5.

7. The non-conjugated receptor-receptor type pyrene diimide polymer according to claim 3, characterized in that: The non-conjugated receptor-receptor type pyrene diimide polymer is selected from any one of the compounds represented by the following structural formulas: Wherein, n represents any value between 10-30, x represents any value between 1-10, preferably any value between 1-3; y represents any value between 1-10, preferably any value between 1-3.

8. A method for preparing the non-conjugated receptor-receptor type pyrene diimide polymer according to claim 1, characterized in that: The method comprises non-conjugated polymerization of a pyrene diimide unit and a conjugated acceptor unit; Preferably, the synthesis is carried out according to the following synthesis route: Preferably, the method comprises: mixing x mol of compound 1, y mol of compound 2, (x+y) mol of compound 3 and 2(x+y) L of solvent and reacting them at 50-80° C. under an inert gas atmosphere.

9. A cathode interface material, characterized in that: It comprises the non-conjugated linked receptor-receptor type pyrene diimide polymer as claimed in claim 1.

10. A semiconductor device, characterized in that: It is prepared by the cathode interface material according to claim 9, Preferably, the semiconductor device comprises an optoelectronic device; Preferably, the optoelectronic device comprises any one of an electroluminescent device, a field effect transistor, a photodetector device and a solar cell device; Preferably, the solar cell device comprises an organic solar cell device; Preferably, the organic solar cell device comprises a cathode interface layer, wherein the cathode interface layer is prepared by the cathode interface material according to claim 9; Preferably, the cathode interface layer has a thickness of 6-121 nm.

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