Application of solid additive in organic solar cell and cell preparation method

Abstract

The invention provides an application of a solid additive in an organic solar cell and the solar cell. The structure of the solid additive provided by the invention is that a methoxy group and a halogen atom simultaneously exist in a benzene nucleus side group. The solid additive can effectively regulate and control the morphology of an active layer so as to improve the performance of a photovoltaic device, and after the solid additive is added, receptor molecules are arranged more tightly and orderly in the active layer, so that the physical process of internal carriers is improved, exciton dissociation is enhanced, charge transfer is improved, charge recombination is reduced, and the performance of the photovoltaic device is improved. Therefore, the short-circuit current density and the filling factor of a cell device are greatly improved, and relatively high photoelectric conversion efficiency is obtained. Besides, in the organic solar cell preparation method provided by the invention, the solid additive concentration, the annealing temperature and the annealing time are systematically optimized, so that the prepared organic solar cell has relatively high photoelectric conversion efficiency, and compared with a traditional liquid additive cell device, the photoelectric conversion efficiency is greatly improved.

Description

Technical Field

[0001] This application relates to the field of organic solar cell technology, and more specifically, to the application of a solid additive in organic solar cells and a method for cell fabrication. Background Technology

[0002] Currently, due to the unrestrained exploitation and use of fossil fuels, their reserves are rapidly decreasing, and traditional fossil fuels such as coal, oil, and natural gas are facing depletion. Humanity urgently needs to solve the energy shortage problem. At the same time, the large amounts of greenhouse gases emitted from the combustion of fossil fuels are exacerbating global warming. Under this severe situation, finding sustainable and clean alternative energy sources has become a top priority, and organic solar cells (OSCs) have attracted much attention due to their numerous advantages, including light weight, flexibility, high indoor light conversion efficiency, and semi-transparency.

[0003] With the rapid development of organic solar cell technology, improving device efficiency and stability has become a key research focus. A crucial aspect of optimizing organic solar cell performance lies in precisely controlling the microstructure and aggregation state of the active layer. The addition of solvent additives is one of the simplest and most effective strategies for optimizing the morphology of the active layer. By utilizing the selective solubility of donors or acceptors, it extends the film drying time, thereby effectively regulating phase separation and molecular orientation of the active layer. However, its high boiling point and residue issues limit its long-term stability and commercial application. Compared to liquid additives, volatile solid additives not only retain the morphology control capabilities of liquid additives but also rapidly evaporate during film formation, effectively avoiding residue problems and thus improving device efficiency and stability.

[0004] Therefore, seeking a solid additive to effectively regulate the morphology of the active layer, significantly optimize the molecular stacking structure, thereby improving charge transport efficiency and enhancing device stability has enormous scientific impact and practical significance. Summary of the Invention

[0005] To achieve the above objectives, this application provides an application of a solid additive in organic solar cells and a method for cell fabrication. The solid additive provided in this application has a structure in which methoxy and halogen atoms coexist in the benzene nucleus side group, i.e., a methoxy-halobenzene nucleus solid additive. This solid additive can effectively regulate the morphology of the active layer, thereby improving the performance of photovoltaic devices. After adding this solid additive, the acceptor molecules in the active layer are arranged more tightly and orderly, thereby improving the internal carrier physics processes, enhancing exciton dissociation, improving charge transport, and reducing charge recombination, thus significantly increasing the short-circuit current density and fill factor of the cell device, achieving higher photoelectric conversion efficiency.

[0006] The first objective of this invention is to provide an application of a solid additive in organic solar cells. To achieve the above objective, this invention provides the following technical solution:

[0007] The application of a solid additive in organic solar cells, wherein the solid additive is a methoxy-halogenated benzene ring solid additive, and the structure of the solid additive is such that methoxy and halogen atoms coexist in the benzene ring side group.

[0008] Furthermore, the solid additive is a compound represented by at least one of the following:

[0009]

[0010] Where R is OCH3;

[0011] X is selected from one or more of F, Cl, Br, I, CH2F, CH2Cl, CH2Br, and CH2I.

[0012] Preferably, the solid additives include, but are not limited to, 3,5-dichloroanisole, 3,5-dibromoanisole, 1,3,5-triiodo-2,4,6-trimethoxybenzene, 1,2,3,4,5-pentachloro-6-methoxybenzene, 1,2,4,5-tetrabromo-3,6-dimethoxybenzene, 1-bromo-3,5-dimethoxybenzene, 1-chloro-3,5-dimethoxybenzene, 1,4-dibromo-2,5-dimethoxybenzene, 1,2-bis(bromomethyl)-4-methoxybenzene, and 1,4-bis(chloromethyl)-2,5-dimethoxybenzene.

[0013] More preferably, the solid additives include, but are not limited to, 1-bromo-3,5-dimethoxybenzene, 1-chloro-3,5-dimethoxybenzene, 3,5-dibromoanisole, and 3,5-dichloroanisole.

[0014] A second objective of this invention is to provide an organic solar cell comprising the aforementioned solid additives. To achieve the above objective, this invention provides the following technical solution:

[0015] An organic solar cell, the structure of which, from bottom to top, includes a transparent substrate, a transparent electrode layer, a hole transport layer, a photoactive layer, an electron transport layer, and a metal electrode layer; the material of the photoactive layer includes a donor material, an acceptor material, and the aforementioned solid additives.

[0016] Furthermore, the donor material is PM6 or D18, and the acceptor material is one of L8-BO, Y6, and BTP-eC9.

[0017] Furthermore, when the donor material and acceptor material are PM6:L8-BO, PM6:Y6, or PM6:BTP-eC9, the mass ratio of the donor material to the acceptor material is 1:1.2; when the donor material and acceptor material are D18:Y6 or D18:L8-BO, the mass ratio of the donor material to the acceptor material is 1:1.6.

[0018] Furthermore, the amount of the solid additive added is 30 to 120% wt of the total weight of the donor and acceptor materials.

[0019] Furthermore, the transparent substrate includes transparent glass, polymethyl methacrylate (PET) transparent film, polyimide (PI) transparent film, polyethersulfone (PES) transparent film, and polyethylene naphthalate (PEN) transparent film.

[0020] Furthermore, the transparent electrode includes indium tin oxide (ITO), fluorine-doped tin oxide (FTO), metal nanowires, low-dimensional carbon materials, and conductive polymer films (PEDOT).

[0021] Furthermore, the hole transport layer material includes one or more of PEDOT:PSS, NiOx, MoO3, CuSCN, and 2PACz.

[0022] The electron transport layer material includes one or more of PFN-Br, PFN, PDINO, TiO2, SnO2, ZnO, PDINN, and PNDIT-F3N.

[0023] Preferably, the hole transport layer is PEDOT:PSS or 2PACz.

[0024] Preferably, the electron transport layer is PDINN or PNDIT-F3N.

[0025] Furthermore, the metal electrode layer includes indium tin oxide (ITO), gold, silver, copper, aluminum, calcium electrodes, silver nanowires, and a conductive polymer film.

[0026] The third objective of this invention is to provide a method for preparing the above-mentioned organic solar cell, employing the following technical solution:

[0027] A method for preparing an organic solar cell includes the following steps:

[0028] Step 1: After marking the ITO conductive glass, place it in alcohol and sonicate at room temperature for 0.5 to 1 hour. Then, use cleaning solution, ultrapure water and ethanol as solvents for ultrasonic cleaning in sequence. After cleaning, dry it and perform ultraviolet-ozone treatment.

[0029] Step 2: Dissolve the hole transport layer material in a solvent to prepare a hole transport layer solution with a concentration of 0.1-3 mg / mL for later use. Take the hole transport layer solution and drop it onto the surface of ITO conductive glass. Spin-coat and place it on a hot stage for annealing. The resulting film is the hole transport layer.

[0030] Step 3: Dissolve the donor material and acceptor material in a solvent, stir at 80-120℃ for 1-3.5h, add solid additives and stir evenly to form a photoactive layer solution, take the photoactive layer solution and drop it onto the hole transport layer, spin-coat and place it on a hot table for annealing to form a photoactive layer film.

[0031] Step 4: Dissolve the electron transport layer material in a solvent to prepare an electron transport layer solution with a concentration of 0.1-3 mg / mL for later use, and spin-coat it onto the photoactive layer film obtained in step 3 to form an electron transport layer;

[0032] Step 5: Transfer the wafer prepared in Step 4 into the vacuum evaporation chamber, and heat it at a depth of 1×10⁻⁶. -5 Metal electrode layers are deposited on the electron transport layer under a vacuum of Pa.

[0033] Furthermore, in step 2, the spin coating speed is 2000–6000 rpm, the spin coating time is 20–40 s, the annealing temperature is 80–200℃, and the time is 5–30 min.

[0034] Furthermore, the solvent in step 2 includes one or more of methanol, ethanol, water, tetrahydrofuran, chlorobenzene, and toluene.

[0035] Furthermore, in step 2, the volume of hole transport layer solution drawn is 15–30 μL.

[0036] Furthermore, in step 3, the spin coating speed is 2000–6000 rpm, the spin coating time is 20–40 s, the annealing temperature is 80–200℃, and the time is 5–30 min.

[0037] Furthermore, in step 3, the concentration of the donor material is 3–10 mg / mL, the concentration of the acceptor material is 3–10 mg / mL, and the concentration of the solid additive is 3–15 mg / mL.

[0038] Furthermore, in step 3, the volume of the photoactive layer solution taken is 15–30 μL.

[0039] Furthermore, the solvent in step 3 includes one or more of tetrahydrofuran, chloroform, chlorobenzene, o-dichlorobenzene, and toluene.

[0040] Furthermore, in step 4, the spin coating speed is 2000–6000 rpm, and the spin coating time is 20–40 s.

[0041] Furthermore, the solvent in step 4 includes one or more of methanol, ethanol, water, tetrahydrofuran, chlorobenzene, and toluene.

[0042] Furthermore, in step 4, the volume of the electron transport layer solution drawn is 15–30 μL.

[0043] The technical solution provided in this application has at least the following advantages compared to the prior art:

[0044] 1. The solid additive provided by this invention is a novel solid additive in which methoxy and halogen atoms coexist in the side group of the benzene ring. This solid additive can effectively regulate the morphology of the active layer of organic solar cells, thereby improving the performance of photovoltaic devices. After the addition of this solid additive, the acceptor molecules are arranged more compactly and orderly in the active layer, thereby improving the internal carrier physics process, enhancing exciton dissociation, improving charge transport and reducing charge recombination, thereby significantly increasing the short-circuit current density and fill factor of the battery device, and thus obtaining a higher photoelectric conversion efficiency. Compared with traditional liquid additives, this novel solid additive can volatilize during the film formation process, avoiding the residue of harmful substances, thereby improving the long-term stability of the device.

[0045] 2. In the organic solar energy preparation method provided by this invention, through systematic optimization of the concentration of solid additives, annealing temperature, and annealing time, the solid additives 1-bromo-3,5-dimethoxybenzene (C8H9BrO2), 1-chloro-3,5-dimethoxybenzene (C8H9ClO2), 3,5-dibromoanisole (C6H6Br2O), and 3,5-dichloroanisole (C6H6Cl2O) achieved photoelectric conversion efficiencies as high as 18.77%, 19.07%, 18.41%, and 19.11% respectively in the D18:L8-BO system battery. High photoelectric conversion efficiencies were also achieved in other systems. Compared with the photoelectric conversion efficiency of traditional liquid additive battery devices, the photoelectric conversion efficiency is significantly improved, indicating that the solid additives of this invention achieve coordinated control of the morphology of donor and acceptor materials in the photoactive layer, and have good universality in different battery systems. Attached Figure Description

[0046] Figure 1 A structural diagram of an organic solar cell device provided in an embodiment of the present invention;

[0047] Figure 2 Solid additives include 1-bromo-3,5-dimethoxybenzene (C8H9BrO2) and 1-chloro-3,5-dimethoxybenzene (C8H9ClO2), while the traditional liquid additive is 1,8-diiodooctane (C8H9BrO2). 16 I2) Processing the JV curves of battery devices based on the PM6:L8-BO system (i.e., Example 1, Example 2 and Comparative Example 1);

[0048] Figure 3 Storage stability graphs of PM6:L8-BO system battery devices treated with solid additives 1-chloro-3,5-dimethoxybenzene, 1-bromo-3,5-dimethoxybenzene and conventional liquid additive 1,8-diiodooctane (i.e., Example 1, Example 2 and Comparative Example 1).

[0049] Figure 4 Solid additives 3,5-dibromoanisole (C6H6Br2O) and 3,5-dichloroanisole (C6H6Cl2O) and traditional liquid additive 1-chloronaphthalene (C 10 JV curves of PM6:Y6-based battery devices (i.e., Examples 3, 4, and Comparative Example 2) were processed using H7Cl. Detailed Implementation

[0050] To enable those skilled in the art to better understand this application, the following detailed description is provided in conjunction with embodiments and accompanying drawings. However, it should be understood that the following embodiments are merely preferred embodiments of this application, and the scope of protection claimed in this application shall be determined by the scope defined in the claims.

[0051] In the description of this invention, it should be noted that unless specific conditions are specified in the examples, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments whose manufacturers are not specified are all commercially available products.

[0052] <Example>

[0053] An embodiment of the present invention provides an application of a solid additive in organic solar cells. The solid additive is a methoxy-halogenated benzene ring solid additive, wherein the structure of the solid additive is such that methoxy and halogen atoms coexist in the benzene ring side group.

[0054] In embodiments of the present invention, the solid additive is at least one of the following compounds:

[0055]

[0056] Where R is OCH3;

[0057] X is selected from one or more of F, Cl, Br, I, CH2F, CH2Cl, CH2Br, and CH2I.

[0058] In embodiments of the present invention, the solid additives include, but are not limited to, 3,5-dichloroanisole, 3,5-dibromoanisole, 1,3,5-triiodo-2,4,6-trimethoxybenzene, 1,2,3,4,5-pentachloro-6-methoxybenzene, 1,2,4,5-tetrabromo-3,6-dimethoxybenzene, 1-bromo-3,5-dimethoxybenzene, 1-chloro-3,5-dimethoxybenzene, 1,4-dibromo-2,5-dimethoxybenzene, 1,2-bis(bromomethyl)-4-methoxybenzene, and 1,4-bis(chloromethyl)-2,5-dimethoxybenzene.

[0059] In embodiments of the present invention, the solid additives include, but are not limited to, 1-bromo-3,5-dimethoxybenzene, 1-chloro-3,5-dimethoxybenzene, 3,5-dibromoanisole, and 3,5-dichloroanisole.

[0060] In an embodiment of the present invention, an organic solar cell is provided, the structure of which, from bottom to top, includes a transparent substrate, a transparent electrode layer, a hole transport layer, a photoactive layer, an electron transport layer, and a metal electrode layer; the material of the photoactive layer includes a donor material, an acceptor material, and the aforementioned solid additives.

[0061] Furthermore, the donor material is PM6 or D18, and the acceptor material is one of L8-BO, Y6, and BTP-eC9; the molecular structural formulas of the donor and acceptor materials are as follows:

[0062] Donor materials:

[0063]

[0064] Receptor material:

[0065]

[0066] In embodiments of the present invention, when the donor material and acceptor material are PM6:L8-BO, PM6:Y6, or PM6:BTP-eC9, the mass ratio of the donor material to the acceptor material is 1:1.2; when the donor material and acceptor material are D18:Y6 or D18:L8-BO, the mass ratio of the donor material to the acceptor material is 1:1.6.

[0067] In embodiments of the present invention, the amount of the solid additive added is 30 to 120% wt of the total weight of the donor and acceptor materials.

[0068] In embodiments of the present invention, the transparent substrate includes transparent glass, a polymethyl methacrylate (PET) transparent film, a polyimide (PI) transparent film, a polyethersulfone (PES) transparent film, and a polyethylene naphthalate (PEN) transparent film.

[0069] In embodiments of the present invention, the transparent electrode comprises indium tin oxide (ITO), fluorine-doped tin oxide (FTO), metal nanowires, low-dimensional carbon materials, and conductive polymer films (PEDOT).

[0070] In embodiments of the present invention, the hole transport layer material includes one or more of PEDOT:PSS, NiOx, MoO3, CuSCN, and 2PACz.

[0071] The electron transport layer material includes one or more of PFN-Br, PFN, PDINO, TiO2, SnO2, ZnO, PDINN, and PNDIT-F3N.

[0072] In embodiments of the present invention, the hole transport layer is PEDOT:PSS or 2PACz.

[0073] In embodiments of the present invention, the electron transport layer is PDINN or PNDIT-F3N.

[0074] In embodiments of the present invention, the metal electrode layer includes indium tin oxide (ITO), gold, silver, copper, aluminum, calcium electrodes, silver nanowires, and a conductive polymer film.

[0075] In an embodiment of the present invention, a method for preparing an organic solar cell is provided, comprising the following steps:

[0076] Step 1: After marking the ITO conductive glass, place it in alcohol and sonicate at room temperature for 0.5 to 1 hour. Then, use cleaning solution, ultrapure water and ethanol as solvents for ultrasonic cleaning in sequence. After cleaning, dry it and perform ultraviolet-ozone treatment.

[0077] Step 2: Dissolve the hole transport layer material in a solvent to prepare a hole transport layer solution with a concentration of 0.1-3 mg / mL for later use. Take the hole transport layer solution and drop it onto the surface of ITO conductive glass. Spin-coat and place it on a hot stage for annealing. The resulting film is the hole transport layer.

[0078] Step 3: Dissolve the donor material and acceptor material in a solvent, stir at 80-120℃ for 1-3.5h, add solid additives and stir evenly to form a photoactive layer solution, take the photoactive layer solution and drop it onto the hole transport layer, spin-coat and place it on a hot table for annealing to form a photoactive layer film.

[0079] Step 4: Dissolve the electron transport layer material in a solvent to prepare an electron transport layer solution with a concentration of 0.1-3 mg / mL for later use, and spin-coat it onto the photoactive layer film obtained in step 3 to form an electron transport layer;

[0080] Step 5: Transfer the wafer prepared in Step 4 into the vacuum evaporation chamber, and heat it at a depth of 1×10⁻⁶. -5Metal electrode layers are deposited on the electron transport layer under a vacuum of Pa.

[0081] In the embodiments of the present invention, in step 2, the spin coating speed is 2000-6000 rpm, the spin coating time is 20-40 s, the annealing temperature is 80-200℃, and the time is 5-30 min.

[0082] In embodiments of the present invention, the solvent in step 2 includes one or more of methanol, ethanol, water, tetrahydrofuran, chlorobenzene, and toluene.

[0083] In an embodiment of the present invention, the volume of hole transport layer solution drawn in step 2 is 15–30 μL.

[0084] In the embodiments of the present invention, in step 3, the spin coating speed is 2000-6000 rpm, the spin coating time is 20-40 s, the annealing temperature is 80-200℃, and the time is 5-30 min.

[0085] In the embodiments of the present invention, the concentration of the donor material in step 3 is 3-10 mg / mL, the concentration of the acceptor material is 3-10 mg / mL, and the concentration of the solid additive is 3-15 mg / mL.

[0086] In an embodiment of the present invention, the volume of photoactive layer solution taken in step 3 is 15-30 μL.

[0087] In embodiments of the present invention, the solvent in step 3 includes one or more of tetrahydrofuran, chloroform, chlorobenzene, o-dichlorobenzene, and toluene.

[0088] In an embodiment of the present invention, the spin coating speed in step 4 is 2000-6000 rpm, and the spin coating time is 20-40 s.

[0089] In embodiments of the present invention, the solvent in step 4 includes one or more of methanol, ethanol, water, tetrahydrofuran, chlorobenzene, and toluene.

[0090] In an embodiment of the present invention, the volume of electron transport layer solution drawn in step 4 is 15–30 μL.

[0091] In the embodiments of the present invention, the ITO conductive glass can be purchased directly. The ITO conductive glass corresponds to a transparent substrate of transparent glass and a transparent electrode of ITO.

[0092] Example 1

[0093] This embodiment provides an organic solar cell, the structure of which is as follows: Figure 1As shown, from bottom to top, it includes a transparent substrate, a transparent electrode layer, a hole transport layer, a photoactive layer, an electron transport layer, and a metal electrode layer; the photoactive layer is made of a donor material, an acceptor material, and a solid additive; the solid additive is 1-bromo-3,5-dimethoxybenzene (C8H9BrO2), the donor material is PM6, and the acceptor material is L8-BO; the hole transport layer material is PEDOT:PSS; the electron transport layer material is PDINN; the transparent substrate is transparent glass; the transparent electrode is ITO; and the metal electrode layer is Ag.

[0094] The above-mentioned method for preparing organic solar energy includes the following steps:

[0095] Step 1: After marking the ITO conductive glass, place it in alcohol and sonicate at room temperature for 1 hour. Then, use cleaning solution, ultrapure water and ethanol as solvents for ultrasonic cleaning in sequence. After cleaning, dry it and perform ultraviolet-ozone treatment.

[0096] Step 2: Take 17 μL of hole transport layer solution and drop it onto the surface of ITO conductive glass. Spin coat at 4000 rpm for 30 s, then place it on a hot plate for annealing at 150℃ for 15 min. The resulting film is the hole transport layer.

[0097] Step 3: Dissolve the donor and acceptor materials in chloroform at a mass ratio of 1:1.2 and a concentration of 7 mg / mL. Stir at 100°C for 2.5 h, add a solid additive and stir until homogeneous to form a photoactive layer solution. The concentration of the solid additive is 7 mg / mL. Take 17 μL of the photoactive layer solution and drop it onto the hole transport layer. Spin coat at 3000 rpm for 30 s, then place on a hot plate for annealing at 85°C for 5 min to form a photoactive layer film.

[0098] Step 4: Dissolve the electron transport layer material in chloroform to prepare an electron transport layer solution with a concentration of 1 mg / mL for later use. Spin-coat the solution at 3500 rpm for 30 seconds onto the photoactive layer film obtained in step 3 to form an electron transport layer.

[0099] Step 5: Transfer the wafer prepared in Step 4 into the vacuum evaporation chamber, and heat it at a depth of 1×10⁻⁶. -5 Metal electrode layers are deposited on the electron transport layer under a vacuum of Pa.

[0100] Example 2

[0101] The difference between Example 2 and Example 1 is that the solid additive used in this example is 1-chloro-3,5-dimethoxybenzene (C8H9ClO2), while the rest are the same.

[0102] Example 3

[0103] The difference between Example 3 and Example 1 is that the solid additive used in this example is 3,5-dibromoanisole (C6H6Br2O) with a concentration of 4 mg / mL; the hole transport layer material is 0.3 mg / mL 2PACz; the acceptor material is Y6; and the rest are the same.

[0104] Example 4

[0105] The difference between Example 4 and Example 3 is that the solid additive used in this example is 3,5-dichloroanisole (C6H6Cl2O), while the rest are the same.

[0106] Example 5

[0107] The difference between Example 5 and Example 1 is that the donor material in this example is D18, the acceptor material is Y6, the mass ratio of the donor material to the acceptor material is 1:1.6, the concentration of the donor material and the acceptor material is 4 mg / mL, the electron transport layer material is PNDIT-F3N, and the concentration is 1.2 mg / mL. All other aspects are the same.

[0108] Example 6

[0109] The difference between Example 6 and Example 5 is that the receptor material in Example 6 is L8-BO, while all other aspects are the same.

[0110] Example 7

[0111] The difference between Example 7 and Example 5 is that the solid additive in Example 7 is 1-chloro-3,5-dimethoxybenzene (C8H9ClO2) with a concentration of 7 mg / mL, while the rest are the same.

[0112] Example 8

[0113] The difference between Example 8 and Example 7 is that the receptor material in Example 8 is L8-BO, while the rest are the same.

[0114] Example 9

[0115] The difference between Example 9 and Example 1 is that the donor material is D18, the acceptor material is Y6, the mass ratio of the donor material to the acceptor material is 1:1.6, and the concentration of the donor material and the acceptor material is 4 mg / mL; the solid additive is 3,5-dibromoanisole (C6H6Br2O) with a concentration of 4 mg / mL, and all other aspects are the same.

[0116] Example 10

[0117] The difference between Example 10 and Example 9 is that the receptor material in Example 10 is L8-BO, while the rest are the same.

[0118] Example 11

[0119] The difference between Example 11 and Example 1 is that the solid additive in this example is 3,5-dichloroanisole (C6H6Cl2O), while the rest are the same.

[0120] Example 12

[0121] The difference between Example 12 and Example 1 is that the donor material in this example is PM6, the acceptor material is BTP-eC9, the mass ratio of the donor material to the acceptor material is 1:1.6, and the concentration of the donor material and the acceptor material is 4 mg / mL; the solid additive is 3,5-dichloroanisole (C6H6Cl2O) with a concentration of 4 mg / mL, and all other aspects are the same.

[0122] Example 13

[0123] The difference between Example 13 and Example 1 is that the donor material is D18, the acceptor material is Y6, the mass ratio of the donor material to the acceptor material is 1:1.6, and the concentration of the donor material and the acceptor material is 4 mg / mL; the solid additive is 3,5-dichloroanisole (C6H6Cl2O) with a concentration of 4 mg / mL, and all other aspects are the same.

[0124] Example 14

[0125] The difference between Example 14 and Example 13 is that the receptor material is L8-BO, while all other aspects are the same.

[0126] Comparative Example 1

[0127] The difference between Comparative Example 1 and Example 1 is that Comparative Example 1 uses the solvent additive 1,8-diiodooctane (C8H12O3). 16 The I2 was at a concentration of 0.25% (v / v), instead of the solid additive in Example 1, but otherwise the same.

[0128] Comparative Example 2

[0129] The difference between Comparative Example 1 and Example 3 is that Comparative Example 1 uses the solvent additive 1-chloronaphthalene (C 10 The additive used was H7Cl, at a concentration of 0.25% (v / v), instead of the solid additive in Example 3, but otherwise identical.

[0130] Comparative Example 3

[0131] The difference between Comparative Example 3 and Example 5 is that in this comparative example, the solvent additive is 1,8-diiodooctane (C8H12O3). 16 The concentration of I2 was 0.25% (v / v), and all other parameters were the same.

[0132] Comparative Example 4

[0133] The difference between Comparative Example 4 and Example 6 is that Comparative Example 4 uses 1,8-diiodooctane (C8H4O3) as the solvent additive. 16 The concentration of I2 was 0.25% (v / v), and all other parameters were the same.

[0134] Comparative Example 5

[0135] The difference between Comparative Example 5 and Example 9 is that in this comparative example, the solvent additive is 1-chloronaphthalene (C 10 The concentration of H7Cl was 0.25% (v / v), and all other parameters were the same.

[0136] Comparative Example 6

[0137] The difference between Comparative Example 6 and Example 10 is that in this comparative example, the solvent additive is 1-chloronaphthalene (C 10 The concentration of H7Cl was 0.25% (v / v), and all other parameters were the same.

[0138] Comparative Example 7

[0139] The difference between Comparative Example 7 and Example 11 is that this comparative example uses the solvent additive 1-chloronaphthalene (C 10 The concentration of H7Cl was 0.25% (v / v), and all other parameters were the same.

[0140] Comparative Example 8

[0141] The difference between Comparative Example 7 and Example 12 is that this comparative example uses the solvent additive 1-chloronaphthalene (C 10 The concentration of H7Cl was 0.25% (v / v), and all other parameters were the same.

[0142] A KeithLey 2400 source measurement unit with an AM1.5G spectral light source was used, and its intensity was calibrated to 100 mW cm⁻¹ using a certified standard solar cell. -2 Under these conditions, the JV curves of each embodiment and comparative example were tested; and the battery devices of Embodiment 1, Embodiment 2, and Comparative Example 1 were stored for 1000 hours before their performance was tested. The performance parameters of the battery devices of each embodiment and comparative example are shown in Table 1.

[0143] Table 1. Photoelectric performance parameters of devices prepared in different embodiments and comparative examples.

[0144]

[0145]

[0146] Table 1 shows that the device prepared with Comparative Example 1 (solvent additive 1,8-diiodooctane) has a PCE of 17.92%, a VOC of 0.874V, and a JSC of 26.11 mA cm⁻¹. -2 The FF was 78.48%, while under the same system, the device with the solid additive 1-bromo-3,5-dimethoxybenzene (Example 1) showed better performance, with a PCE of 18.40%, VOC of 0.893V, and JSC of 26.20 mA / cm². -2 The FF was 78.62%; however, the device with the solid additive 1-chloro-3,5-dimethoxybenzene (Example 2) performed best, achieving the highest PCE of 18.51%, VOC of 0.888V, and JSC of 26.34mA cm⁻¹. -2 FF was 79.12%.

[0147] Figure 2 The JV curves of the battery devices in Example 1, Example 2, and Comparative Example 1 are shown. Figure 3 This is a storage stability graph for the battery devices of Example 1, Example 2, and Comparative Example 1. (Source: [Insert graph here]) Figure 2 It can be seen that the battery devices of Examples 1 and 2 are significantly more efficient than Comparative Example 1. The improvement in PCE is attributed to the significant increase in JSC and FF, which is closely related to the morphology of the active layer. Figure 3 It can be seen that after 1000 hours, the battery device of Example 1 retained 90% of its initial efficiency, and Example 2 retained 92% of its initial efficiency, both significantly better than the battery device of Comparative Example 1 (86%). Further estimation of the T80 lifetime (time to retain 80% of the initial PCE) of Examples 1, 2, and Comparative Example 1 shows that the T80 lifetime of the battery device of Example 1 is 2664 hours, better than Comparative Example 1 (T80 = 2246 hours); compared to Comparative Example 1, the battery device of Example 1 exhibits significant storage stability; the T80 lifetime of the battery device of Example 2 is 4148 hours, significantly better than both Examples 1 and Comparative Example 1, indicating that the battery device using the 1-chloro-3,5-dimethoxybenzene solid additive has excellent storage stability.

[0148] The device prepared with Comparative Example 2 (solvent additive 1-chloronaphthalene) had a PCE of 17.08%, a VOC of 0.842V, and a JSC of 27.38mA cm⁻¹. -2The FF was 74.08%; however, under the same system, the device with the solid additive 3,5-dibromoanisole (Example 3) exhibited better performance, with a PCE of 17.36%, a VOC of 0.824V, and a JSC of 27.46mA cm⁻¹. -2 The FF was 76.71%. Under the same system, the device with the solid additive 3,5-dichloroanisole (Example 4) achieved an excellent PCE of 18.13%, a VOC of 0.827V, and a JSC of 28.15mA. -2 The FF value was 77.85%.

[0149] Figure 4 The JV curves of the battery devices in Examples 3, 4, and Comparative Example 2 are shown; Figure 4 It can be seen that the battery devices of Examples 3 and 4 have significantly better efficiency than those of Comparative Example 2, and the solid additives of the present invention have greatly improved JSC and FF.

[0150] In the D18:Y6 system, the PCE values ​​of the device prepared in Example 5 (with solid additive 1-bromo-3,5-dimethoxybenzene), the device prepared in Example 7 (with solid additive 1-chloro-3,5-dimethoxybenzene), and the device prepared in Comparative Example 3 (with solvent additive 1,8-diiodooctane) were 18.29%, 18.47%, and 18.03%, respectively.

[0151] In the D18:L8-BO system, the PCE values ​​of the device prepared in Example 6 (with the addition of solid additive 1-bromo-3,5-dimethoxybenzene), Example 8 (with the addition of solid additive 1-chloro-3,5-dimethoxybenzene), and Comparative Example 4 (with the addition of solvent additive 1,8-diiodooctane) were 18.77%, 19.07%, and 17.99%, respectively. The results show that the devices using 1-bromo-3,5-dimethoxybenzene and 1-chloro-3,5-dimethoxybenzene additives exhibit superior photovoltaic performance compared to the devices treated with solvent additive 1,8-diiodooctane. Furthermore, as shown in Table 1, the solid additives of the present invention have good universality in organic solar cells with different active layer material systems.

[0152] In the D18:Y6 system, the PCE values ​​of the devices prepared in Example 9 (with added 3,5-dibromoanisole), Example 13 (with added 3,5-dichloroanisole), and Comparative Example 5 (with solvent additive 1-chloronaphthalene) were 18.32%, 18.95%, and 17.35%, respectively. In the D18:L8-BO system, the PCE values ​​of the devices prepared in Example 10 (with added 3,5-dibromoanisole), Example 14 (with added 3,5-dichloroanisole), and Comparative Example 6 (with solvent additive 1-chloronaphthalene) were 18.41%, 19.11%, and 15.99%, respectively. Therefore, compared with devices treated with the traditional additive 1-chloronaphthalene, devices using solid additives 3,5-dibromoanisole and 3,5-dichloroanisole exhibited superior synergistic improvement effects on FF and JSC in both systems.

[0153] In the PM6:L8-BO system, the PCE values ​​of devices in Example 11 (with 3,5-dichloroanisole as solid additive) and Comparative Example 7 (with 1-chloronaphthalene as solvent additive) were 18.42% and 17.12%, respectively. In the PM6:BTP-eC9 system, the PCE values ​​of devices in Example 12 (with 3,5-dichloroanisole as solid additive) and Comparative Example 8 (with 1-chloronaphthalene as solvent additive) were 18.27% and 16.71%, respectively. The results show that compared with devices treated with 1-chloronaphthalene as solvent additive, the solid additive 3,5-dichloroanisole exhibits superior photovoltaic performance in different systems.

Claims

1. The application of a solid additive in organic solar cells, characterized in that, The solid additive has a structure in which methoxy and halogen atoms coexist on the side groups of the benzene ring.

2. The application of the solid additive according to claim 1 in organic solar cells, characterized in that, The solid additive is at least one of the following compounds: Where R is OCH3; X is selected from one or more of F, Cl, Br, I, CH2F, CH2Cl, CH2Br, and CH2I.

3. The application of the solid additive according to claim 2 in organic solar cells, characterized in that, The solid additives include 3,5-dichloroanisole, 3,5-dibromoanisole, 1,3,5-triiodo-2,4,6-trimethoxybenzene, 1,2,3,4,5-pentachloro-6-methoxybenzene, 1,2,4,5-tetrabromo-3,6-dimethoxybenzene, 1-bromo-3,5-dimethoxybenzene, 1-chloro-3,5-dimethoxybenzene, 1,4-dibromo-2,5-dimethoxybenzene, 1,2-bis(bromomethyl)-4-methoxybenzene, and 1,4-bis(chloromethyl)-2,5-dimethoxybenzene.

4. An organic solar cell, characterized in that, The organic solar cell structure, from bottom to top, includes a transparent substrate, a transparent electrode layer, a hole transport layer, a photoactive layer, an electron transport layer, and a metal electrode layer; the material of the photoactive layer includes a donor material, an acceptor material, and a solid additive as described in any one of claims 1 to 3.

5. The organic solar cell according to claim 4, characterized in that, The donor material is PM6 or D18, and the acceptor material is one of L8-BO, Y6, and BTP-eC9.

6. The organic solar cell according to claim 5, characterized in that, When the donor material and acceptor material are PM6:L8-BO, PM6:Y6, or PM6:BTP-eC9, the mass ratio of the donor material to the acceptor material is 1:1.2; when the donor material and acceptor material are D18:Y6 or D18:L8-BO, the mass ratio of the donor material to the acceptor material is 1:1.

6.

7. The organic solar cell according to claim 4, characterized in that, The amount of the solid additive added is 30 to 120% wt of the total weight of the donor and acceptor materials.

8. The method for preparing the organic solar cell according to any one of claims 4 to 7, characterized in that, Includes the following steps: Step 1: After marking the ITO conductive glass, place it in alcohol and sonicate at room temperature for 1 hour. Then, use cleaning solution, ultrapure water and ethanol as solvents for ultrasonic cleaning in sequence. After cleaning, dry it and perform ultraviolet-ozone treatment. Step 2: Dissolve the hole transport layer material in a solvent to prepare a hole transport layer solution with a concentration of 0.1-3 mg / mL for later use. Take the hole transport layer solution and drop it onto the surface of ITO conductive glass. Spin-coat and place it on a hot stage for annealing. The resulting film is the hole transport layer. Step 3: Dissolve the donor material and acceptor material in a solvent, stir at 80-120℃ for 1-3.5h, add solid additives and stir evenly to form a photoactive layer solution, take the photoactive layer solution and drop it onto the hole transport layer, spin-coat and place it on a hot table for annealing to form a photoactive layer film. Step 4: Dissolve the electron transport layer material in a solvent to prepare an electron transport layer solution with a concentration of 0.1-3 mg / mL for later use, and spin-coat it onto the photoactive layer film obtained in step 3 to form an electron transport layer; Step 5: Transfer the wafer prepared in Step 4 into the vacuum evaporation chamber, and heat it at a depth of 1×10⁻⁶. -5 Metal electrode layers are deposited on the electron transport layer under a vacuum of Pa.

9. The method for preparing an organic solar cell according to claim 8, characterized in that, In step 3, the concentration of the donor material is 3–10 mg / mL, the concentration of the acceptor material is 3–10 mg / mL, and the concentration of the solid additive is 3–15 mg / mL.

10. The method for preparing an organic solar cell according to claim 7, characterized in that, In step 3, the volume of the photoactive layer solution taken is 15-30 μL.

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