Flexible organic solar cell and method of making the same

Abstract

The present application provides a flexible organic solar cell, wherein the flexible organic solar cell comprises a flexible transparent electrode, an electron transport layer, an active layer, a hole transport layer and an anode layer, wherein the active layer comprises a mixture of PM6 and a non-fullerene acceptor Y6 or a derivative thereof; or, a mixture of PM6 and PC 61 BM and Y6; or a combination thereof, wherein R in PM6 and Y6 is each independently a C1-C 20 alkyl. Furthermore, the present application also provides a preparation method of a flexible organic solar cell, wherein the flexible organic solar cell has high efficiency and high stability.

Description

Technical Field

[0001] This application belongs to the field of flexible electronics. Specifically, this application relates to flexible solar cells and methods for their fabrication. Background Technology

[0002] Flexible electronic products, such as wearable devices, are gaining increasing popularity, and their development relies heavily on flexible electrodes. High-performance flexible electrodes should simultaneously possess high conductivity, high light transmittance, low roughness, and excellent bending performance. Recently, in Chinese Patent Application No. 201910514527.9, the inventors used flexible transparent electrodes to fabricate a flexible solar cell with an energy conversion efficiency comparable to that of a rigid solar cell. However, in practical applications, there is still a pursuit for flexible solar cells that simultaneously achieve excellent energy conversion efficiency and stability.

[0003] Recently, significant breakthroughs have been achieved in the performance of organic photovoltaic devices based on the development of newly emerging star molecules such as Y6-type non-fullerene acceptor materials. However, there remains a demand for flexible organic solar cells with high energy conversion efficiency and high stability based on Y6 and its derivatives as acceptor materials. Summary of the Invention

[0004] The purpose of this invention is to provide a flexible organic solar cell with high stability and high efficiency, as well as a method for preparing the flexible organic solar cell.

[0005] On the one hand, this application provides a flexible organic solar cell, which includes:

[0006] Flexible transparent electrode;

[0007] Electron transport layer;

[0008] Active layer;

[0009] Hole transport layer; and

[0010] Anode layer,

[0011] The active layer comprises a mixture of PM6 and a non-fullerene acceptor Y6 or a derivative thereof; or, PM6 and PC. 61 A mixture of BM and Y6; or a combination thereof,

[0012]

[0013] In PM6 and Y6, R is independently C1-C. 20 alkyl.

[0014] In some embodiments, the flexible transparent electrode includes a flexible transparent substrate and a conductive film disposed on the surface of the flexible transparent substrate.

[0015] In some embodiments, the thickness of the flexible transparent substrate is 1 to 300 μm.

[0016] In some embodiments, the conductive film has a thickness of 30 nm to 1 μm and a surface roughness Ra of 5 to 10 nm. In some embodiments, the conductive film comprises an electrolyte and conductive nanomaterials in a weight ratio of 1:4 to 1:8.

[0017] In some embodiments, the electrolyte is a cationic electrolyte or an anionic electrolyte.

[0018] In some embodiments, the conductive nanomaterial is a nanowire or nanotube and is distributed in the conductive film in a lattice-like structure. In some embodiments, the conductive nanomaterial has a diameter of 10 to 100 nm and a length of 15 to 35 μm.

[0019] In some embodiments, the flexible organic solar cell further includes an interface modification layer.

[0020] In some embodiments, the electron transport layer comprises any one or any combination of ZnO, TiO2, or SnO2 nanoparticles.

[0021] In some embodiments, the interface modification layer comprises a conductive polymer PFN-Br or PFN or a combination thereof.

[0022] In some implementations, the hole transport layer comprises any one or any combination of MoO3, V2O5, or WO3.

[0023] In some embodiments, the anode layer comprises any one or any combination of silver, gold, or aluminum.

[0024] In some embodiments, when the active layer comprises a mixture of PM6 and non-fullerene receptor Y6 or its derivatives, the weight ratio of PM6 to non-fullerene receptor Y6 or its derivatives in the mixture is from 1:0.6 to 1:2.

[0025] In some embodiments, the non-fullerene receptor Y6 or a derivative thereof is the following compound:

[0026]

[0027] In some implementations, the active layer comprises PM6 and PC 61 When BM is mixed with Y6, PM6 and PC 61 The weight ratio of BM to Y6 in the mixture is 1:0.02-0.4:0.6-2.

[0028] On the other hand, this application provides a method for preparing flexible organic solar cells, which includes:

[0029] Provide flexible transparent electrodes;

[0030] An electron transport layer is formed on the flexible transparent electrode;

[0031] An active layer is formed on the electron transport layer;

[0032] A hole transport layer is formed on the active layer; and

[0033] An anode layer is formed on the hole transport layer.

[0034] The active layer comprises a mixture of PM6 and a non-fullerene acceptor Y6 or a derivative thereof; or, PM6 and PC. 61 A mixture of BM and Y6; or a combination thereof,

[0035]

[0036]

[0037] In PM6 and Y6, R is independently C1-C. 20 alkyl.

[0038] In some embodiments, providing a flexible transparent electrode includes forming a conductive thin film on a flexible transparent substrate.

[0039] In some embodiments, forming the electron transport layer includes coating the flexible transparent electrode with any one or any combination of ZnO, TiO2, or SnO2 nanoparticle dispersions.

[0040] In some embodiments, forming the active layer comprises mixing PM6 with a non-fullerene receptor Y6 or a derivative thereof; or, PM6 and PC 61 The mixture of BM and Y6 is coated onto the electron transport layer in solution form.

[0041] In some embodiments, forming the hole transport layer includes depositing any one or any combination of MoO3, V2O5, or WO3 onto the active layer.

[0042] In some embodiments, forming the anode layer includes depositing any one or any combination of silver, gold, or aluminum onto the hole transport layer.

[0043] In other embodiments, the method further includes forming an interface modification layer between the electron transport layer and the active layer.

[0044] In some embodiments, forming the interface modification layer includes coating a conductive polymer PFN-Br or a PFN solution or a combination thereof between the electron transport layer and the active layer.

[0045] In some embodiments, when the active layer comprises a mixture of PM6 and non-fullerene receptor Y6 or its derivatives, the weight ratio of PM6 to non-fullerene receptor Y6 or its derivatives in the mixture is from 1:0.6 to 1:2.

[0046] In some embodiments, the non-fullerene receptor Y6 or a derivative thereof is the following compound:

[0047]

[0048] In some implementations, the active layer comprises PM6 and PC 61 When BM is mixed with Y6, PM6 and PC 61 The weight ratio of BM to Y6 in the mixture is 1:0.02-0.4:0.6-2. Attached Figure Description

[0049] Figure 1 and Figure 2 Schematic diagrams of flexible organic solar cells according to exemplary embodiments of this application are shown respectively.

[0050] Figure 3 The current density-voltage curves of flexible organic solar cells and rigid organic solar cells are shown.

[0051] Figure 4 The stability of flexible organic solar cells and rigid organic solar cells is shown. Detailed Implementation Plan

[0052] definition

[0053] The following definitions and methods are provided to better define this application and to guide those skilled in the art in its practice. Unless otherwise stated, the terms are to be understood in accordance with their conventional usage by those skilled in the art. All patent literature, academic papers, and other published materials cited herein are incorporated herein by reference in their entirety.

[0054] As used herein, the terms “optional” or “optionally” mean that the events or circumstances described below may, but are not required to, occur, including both when they occur and when they do not.

[0055] Wherever a range of values ​​is given herein, the range includes its endpoints, as well as all individual integers and fractions within the range, and also includes each narrower range formed by all the various possible combinations of those endpoints and internal integers and fractions, to form a subgroup of a larger group of values ​​within the same extent as each of those narrower ranges is explicitly given.

[0056] As used herein, the term "about" means that a quantity, size, formulation, parameter, or other quantity and characteristic is imprecise and does not need to be exact, but may approximate and / or be greater than or less than an exact value to reflect tolerances, conversion factors, rounding, measurement errors, and other factors known to those skilled in the art. Generally, quantities, sizes, formulations, parameters, or other quantities or characteristics are "about" or "approximate," whether or not such explicit statements are made.

[0057] As used herein, when a component or layer is referred to as being “on” another component or layer, it may be directly on the other component or layer, or there may be an intermediate component or layer. However, when a component or layer is referred to as being “directly on” another component or layer, there is no intermediate component or layer.

[0058] The term “PFN-Br” as used herein refers to a compound having the following structure, which can be prepared by reference (F. Huang, et al., Novel Electroluminescent Conjugated Polyelectrolytes Based on Polyfluorene. Chem. Mater. 16, 708-716 (2004)) or by other known methods.

[0059]

[0060] As used in this article, the term "PFN" refers to compounds having the following structure.

[0061]

[0062] As used herein, the term "PM6" refers to a compound having the following structure, which is commercially available or prepared by known methods, wherein R in formula PM6 is C1-C6. 20 alkyl.

[0063]

[0064] As used herein, the term "Y6" refers to a compound having the following structure, which is commercially available or prepared by known methods, wherein R in formula Y6 is C1-C6. 20 alkyl.

[0065]

[0066] The term "PC" as used in this article 61 "BM" refers to a compound having the following structure, which is commercially available or prepared by known methods.

[0067]

[0068] The present invention aims to provide flexible organic solar cells and methods for their preparation.

[0069] This application utilizes newly developed star molecule Y6 and its derivatives as non-fullerene acceptor materials, and based on the flexible transparent electrode of conductive nanomaterials with a mesh-like structure distribution that exhibit high conductivity, high light transmittance, low roughness, and excellent bending properties prepared by the inventors, to fabricate a flexible organic solar cell with high efficiency and high stability.

[0070] Flexible organic solar cells

[0071] This application provides a flexible organic solar cell, comprising a flexible transparent electrode, an electron transport layer, an active layer, a hole transport layer, and an anode layer. The active layer comprises a mixture of PM6 and a non-fullerene acceptor Y6 or a derivative thereof; or, PM6 and PC. 61 A mixture of BM and Y6; or a combination thereof,

[0072]

[0073] In PM6 and Y6, R is independently C1-C. 20 alkyl.

[0074] In some embodiments, non-limiting examples of R are selected from methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, isobutyl, 2-ethylbutyl, 3,3-dimethylbutyl, n-pentyl, isopentyl, neopentyl, tert-pentyl, 1-methylpentyl, 3-methylpentyl, 2-ethylpentyl, 4-methyl-2-pentyl, n-hexyl, 1-methylhexyl, 2-ethylhexyl, 2-butylhexyl, n-heptyl, 1-methylheptyl, 2,2-dimethylheptyl, 2-ethylheptyl, 2-butylheptyl, n-octyl, tert-octyl, 2-Ethyloctyl, 2-Butyloctyl, 2-Hexyloctyl, 3,7-Dimethyloctyl, n-Nonyl, n-Decyl, 2-Ethyldecyl, 2-Butyldecyl, 2-Hexyldecyl, 2-Ocyldecyl, n-Undecyl, n-Dodecyl, 2-Ethyldodecyl, 2-Butyldodecyl, 2-Hexyldodecyl, 2-Ocyldodecyl, n-Tridecyl, n-Tetradecyl, n-Pentadecanyl, n-Hexadecyl, 2-Ethylhexadecyl, 2-Butylhexadecyl, n-Heptadecanyl, n-Octadecanyl, n-Nondecyl, n-Eicosyl, etc.

[0075] In a preferred embodiment, R is selected from methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, isobutyl, 2-ethylbutyl, 3,3-dimethylbutyl, n-pentyl, isopentyl, neopentyl, tert-pentyl, 1-methylpentyl, 3-methylpentyl, 2-ethylpentyl, 4-methyl-2-pentyl, n-hexyl, 1-methylhexyl, 2-ethylhexyl, 2-butylhexyl, n-heptyl, 1-methylheptyl, 2,2-dimethylheptyl, 2-ethylheptyl, 2-butylheptyl, n-octyl, tert-octyl, 2-ethyloctyl, 2-butyloctyl, 2-hexyloctyl, 3,7-dimethyloctyl, n-nonyl, n-decyl, 2-ethyldecyl, 2-butyldecyl, or 2-hexyldecyl.

[0076] In a more preferred embodiment, R is selected from methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, isobutyl, 2-ethylbutyl, 1-methylpentyl, 2-ethylpentyl, n-hexyl, 1-methylhexyl, 2-ethylhexyl, 2-butylhexyl, 2-ethylheptyl, 2-butylheptyl, n-octyl, tert-octyl, 2-ethyloctyl, 2-butyloctyl, or 2-hexyloctyl. In the most preferred embodiment, R is selected from 2-ethylbutyl, 2-ethylhexyl, 2-ethylpentyl, 2-ethyloctyl, or 2-butyloctyl.

[0077] The flexible organic solar cell has an open-circuit voltage of 0.80-0.90V and a short-circuit current density of 24-30mA / cm². -2 The fill factor is 70%-80%, and the energy conversion efficiency is 15%-18%.

[0078] In some embodiments, the flexible organic solar cell further includes an interface modification layer.

[0079] In some embodiments, the flexible transparent electrode includes a flexible transparent substrate and a conductive film disposed on the surface of the flexible transparent substrate.

[0080] In some embodiments, the thickness of the flexible transparent substrate is 1 to 300 μm, 10 to 280 μm, 20 to 250 μm, 50 to 230 μm, 80 to 200 μm, 100 to 180 μm, or 120 to 150 μm. In some embodiments, the thickness of the flexible transparent substrate is 1 μm, 2 μm, 5 μm, 10 μm, 20 μm, 40 μm, 60 μm, 80 μm, 100 μm, 120 μm, 150 μm, 180 μm, 200 μm, 220 μm, 250 μm, 280 μm, or 300 μm.

[0081] In some embodiments, the thickness of the conductive film is 30 nm to 1 μm, 100 nm to 800 nm, 200 nm to 600 nm, or 300 nm to 500 nm. In specific embodiments, the thickness of the conductive film is 30 nm, 60 nm, 70 nm, 80 nm, 90 nm, 100 nm, 200 nm, 300 nm, 400 nm, 500 nm, 600 nm, 700 nm, 800 nm, 900 nm, or 1 μm. In the embodiments of this application, when the thickness of the conductive film is less than 30 nm, the conductivity of the resulting flexible transparent electrode will be significantly reduced, and the uniformity of the conductive film will also be adversely affected. In the embodiments of this application, when the thickness of the conductive film is greater than 1 μm, the light transmittance of the resulting flexible transparent electrode will be significantly reduced.

[0082] In some embodiments, the surface roughness Ra of the conductive film is 5 to 10 nm or 6 to 8 nm. In specific embodiments, the surface roughness Ra of the conductive film is 5 nm, 6 nm, 7 nm, 8 nm, 9 nm, or 10 nm.

[0083] In some embodiments, the conductive film comprises an electrolyte and conductive nanomaterials. In some embodiments, the weight ratio of the electrolyte to conductive nanomaterials in the conductive film is 1:4 to 1:8, 1:4.5 to 1:7.5, 1:5 to 1:7.5, or 1:6 to 1:7. In specific embodiments, the weight ratio of the electrolyte to conductive nanomaterials in the conductive film is 1:4.0, 1:4.5, 1:5.0, 1:5.5, 1:6.0, 1:7.5, or 1:8.0. In the embodiments of this application, when the weight ratio of the electrolyte to conductive nanomaterials in the conductive film is less than 1:4, the conductivity of the resulting flexible transparent electrode will significantly decrease. In the embodiments of this application, when the weight ratio of the electrolyte to conductive nanomaterials in the conductive film is greater than 1:8, the light transmittance of the resulting flexible transparent electrode will decrease, and the film-forming properties of the resulting conductive film will also be adversely affected, for example, the resulting conductive film may be uneven or have bumps.

[0084] In some embodiments, the conductive nanomaterial is a nanowire or nanotube. In some embodiments, the conductive nanomaterial is distributed in the conductive film in a lattice-like structure.

[0085] In some embodiments, the mesh size of the conductive nanomaterial in the conductive film is approximately 0.1-1 μm × 0.1-1 μm. In specific embodiments, the mesh size of the conductive nanomaterial in the conductive film is 0.1 μm × 0.1 μm, 0.2 μm × 0.2 μm, 0.3 μm × 0.3 μm, 0.4 μm × 0.4 μm, 0.4 μm × 0.6 μm, 0.4 μm × 0.8 μm, 0.5 μm × 0.5 μm, 0.5 μm × 0.7 μm, 0.8 μm × 0.6 μm, 0.8 μm × 0.8 μm, or 1.0 μm × 1.0 μm. In preferred embodiments, the mesh size of the conductive nanomaterial in the conductive film is 0.3 μm × 0.3 μm, 0.4 μm × 0.4 μm, or 0.5 μm × 0.5 μm. In the most preferred embodiment, the mesh size of the conductive nanomaterial in the conductive film is 0.4 μm × 0.4 μm. In this case, the overall light transmittance, conductivity, and roughness of the conductive film are optimal. In an embodiment of this application, when the mesh size of the conductive nanomaterial in the conductive film is less than 0.1 μm × 0.1 μm, the light transmittance of the flexible transparent electrode is affected. In an embodiment of this application, when the mesh size of the conductive nanomaterial in the conductive film is greater than 1.0 μm × 1.0 μm, the conductivity of the flexible transparent electrode is affected.

[0086] In some embodiments, the diameter of the conductive nanomaterial is 10 to 100 nm, 15 to 90 nm, 20 to 80 nm, 30 to 70 nm, 40 to 60 nm, 45 to 55 nm, 12 to 28 nm, 14 to 26 nm, 16 to 24 nm, or 18 to 22 nm. In specific embodiments, the diameter of the conductive nanomaterial is 10 nm, 14 nm, 16 nm, 18 nm, 20 nm, 22 nm, 25 nm, 28 nm, 30 nm, 40 nm, 50 nm, 60 nm, 70 nm, 80 nm, 90 nm, or 100 nm. In the embodiments of this application, when the diameter of the conductive nanomaterial is greater than 100 nm, it adversely affects the conductivity and light transmittance of the flexible transparent electrode.

[0087] In some embodiments, the length of the conductive nanomaterial is 15 to 35 μm, 16 to 32 μm, 18 to 30 μm, 20 to 28 μm, or 22 to 26 μm. In specific embodiments, the length of the conductive nanomaterial is 15 μm, 18 μm, 20 μm, 22 μm, 24 μm, 28 μm, 30 μm, 32 μm, or 35 μm. In the embodiments of this application, when the length of the conductive nanomaterial is less than 15 μm, the conductivity of the obtained flexible transparent electrode is significantly reduced. In the embodiments of this application, when the length of the conductive nanomaterial is greater than 35 μm, the preparation steps of the conductive nanomaterial are more complex and costly.

[0088] In some embodiments, the sheet resistance of the flexible transparent electrode is 0.01 to 20 Ω / sq, 0.02 to 18 Ω / sq, 0.05 to 15 Ω / sq, 0.1 to 12 Ω / sq, 0.2 to 10 Ω / sq, 0.5 to 8 Ω / sq, 1 to 6 Ω / sq, 2.0 to 4 Ω / sq, or 2.5 to 3 Ω / sq. In specific implementations, the sheet resistance of the flexible transparent electrode is 0.01Ω / sq, 0.04Ω / sq, 0.08Ω / sq, 0.1Ω / sq, 0.2Ω / sq, 0.4Ω / sq, 0.8Ω / sq, 1.0Ω / sq, 2.0Ω / sq, 3.0Ω / sq, 4.0Ω / sq, 6.0Ω / sq, 8.0Ω / sq, 10.0Ω / sq, 12.0Ω / sq, 14.0Ω / sq, 16.0Ω / sq, 18.0Ω / sq, or 20Ω / sq.

[0089] In some embodiments, the transmittance of the flexible transparent electrode is 90%-98% or 92%-95%. In specific embodiments, the transmittance of the flexible transparent electrode is 90%, 92%, 93%, 94%, 95%, 96%, 97%, or 98%.

[0090] In some embodiments, the flexibility of the flexible transparent electrode is expressed in terms of a bending radius of 0.5 to 3.0 mm, 1.5 to 2.5 mm, or 1.8 to 2.0 mm.

[0091] In some embodiments, the flexibility of the flexible transparent electrode is expressed in terms of bending radius as 0.5 mm, 1.0 mm, 1.5 mm, 2.0 mm, 2.5 mm, or 3.0 mm.

[0092] In some embodiments, the flexible transparent substrate is selected from polyethylene terephthalate, polyethersulfone resin, polyethylene naphthalate, polycarbonate, polyimide, hexamethylene polypropylene, polyethylene, parylene, polydimethylsiloxane, or combinations thereof.

[0093] In some embodiments, the electrolyte is a cationic electrolyte or an anionic electrolyte.

[0094] In some embodiments, the cationic electrolyte is selected from hexadecyltrimethylammonium chloride, octadecyltrimethylammonium chloride, hexadecyltrimethylammonium bromide, octadecyltrimethylammonium bromide, stearyltrimethylammonium chloride, hexadecyltrimethylammonium toluenesulfonate, or combinations thereof.

[0095] In some embodiments, the anionic electrolyte is sodium polystyrene sulfonate, sodium polyacrylate, sodium dodecylbenzene sulfonate, sodium dodecyl sulfate, sodium polymethacrylate, sodium polyethylene sulfonate, sodium polypolyphosphate, or a combination thereof.

[0096] In some embodiments, the conductive nanomaterial is a carbon nanomaterial, such as carbon nanotubes, carbon nanowires, or graphene nanomaterials. In some embodiments, the conductive nanomaterial is a metallic nanomaterial, such as gold, silver, copper, or aluminum nanomaterials.

[0097] In some implementations, after being repeatedly bent 1000 times, the sheet resistance of the flexible transparent electrode is more than 97% of its initial value.

[0098] In some implementations, after being repeatedly bent 1000 times, the transmittance of the flexible transparent electrode is more than 98% of its initial value.

[0099] In some embodiments, the electron transport layer comprises any one or any combination of ZnO, TiO2, and SnO2 nanoparticles.

[0100] In some embodiments, the interface modification layer comprises a conductive polymer PFN-Br or PFN or a combination thereof.

[0101] In some implementations, the hole transport layer comprises any one or any combination of MoO3, V2O5, or WO3.

[0102] In some embodiments, the anode layer comprises any one or any combination of silver, gold, or aluminum.

[0103] In some embodiments, the thickness of the electron transport layer is 5 to 30 nm, 8 to 29 nm, 12 to 28 nm, 15 to 25 nm, or 18 to 20 nm. In specific embodiments, the thickness of the electron transport layer is 5 nm, 6 nm, 8 nm, 10 nm, 12 nm, 14 nm, 16 nm, 18 nm, 20 nm, 22 nm, 24 nm, 26 nm, 28 nm, or 30 nm. In the embodiments of this application, when the thickness of the electron transport layer is greater than 30 nm, electron recombination occurs during transport.

[0104] In some embodiments, the thickness of the interface modification layer is 10 to 20 nm, 12 to 18 nm, or 14 to 16 nm. In specific embodiments, the thickness of the interface modification layer is 10 nm, 11 nm, 13 nm, 15 nm, 17 nm, 19 nm, or 20 nm. In embodiments of this application, when the thickness of the interface modification layer is greater than 20 nm, holes recombine during transport.

[0105] In some embodiments, the thickness of the active layer is 100 to 150 nm or 110 to 130 nm. In specific embodiments, the thickness of the active layer is 100 nm, 120 nm, 130 nm, 140 nm, or 150 nm. In embodiments of this application, when the thickness of the active layer is less than 100 nm, the current decreases. In embodiments of this application, when the thickness of the active layer is greater than 150 nm, charge is difficult to transport to the electrode, and the probability of carrier recombination increases.

[0106] In some embodiments, the thickness of the hole transport layer is 5 to 30 nm, 8 to 29 nm, 12 to 28 nm, 15 to 25 nm, or 18 to 20 nm. In specific embodiments, the thickness of the hole transport layer is 5 nm, 6 nm, 8 nm, 10 nm, 12 nm, 14 nm, 16 nm, 18 nm, 20 nm, 22 nm, 24 nm, 26 nm, 28 nm, or 30 nm. In the embodiments of this application, when the thickness of the hole transport layer is greater than 30 nm, holes recombine during transport.

[0107] In some embodiments, the thickness of the anode layer is 50 to 100 nm or 60 to 80 nm. In specific embodiments, the thickness of the anode layer is 50 nm, 60 nm, 70 nm, 80 nm, 90 nm, or 100 nm. In the embodiments of this application, when the thickness of the anode layer is less than 50 nm, the flexible organic solar cell will exhibit light leakage. In the embodiments of this application, when the thickness of the anode layer is greater than 100 nm, the cost increases significantly.

[0108] In some embodiments, the open-circuit voltage of the flexible organic solar cell is 0.80-0.90V. In specific embodiments, the open-circuit voltage of the flexible organic solar cell is 0.80V, 0.82V, 0.85V, 0.87V, or 0.90V.

[0109] In some embodiments, the short-circuit current density of the flexible organic solar cell is 24-30 mA cm⁻¹. -2 In a specific implementation, the short-circuit current density of the flexible organic solar cell is 24 mA cm⁻¹. -2 25mA cm -2 26mA cm -2 27mA cm -2 28mA cm -2 29mA cm -2 or 30mA cm -2 .

[0110] In some embodiments, the fill factor of the flexible organic solar cell is 70%-80%. In specific embodiments, the fill factor of the flexible organic solar cell is 70%, 71%, 72%, 74%, 75%, or 80%.

[0111] In some embodiments, the flexible organic solar cell has a power conversion efficiency of 15%-18%. In specific embodiments, the power conversion efficiency of the flexible organic solar cell is 15%, 16%, 17%, or 18%.

[0112] In some embodiments, when the active layer comprises a mixture of PM6 and non-fullerene receptor Y6 or its derivatives, the weight ratio of PM6 to non-fullerene receptor Y6 or its derivatives in the mixture is 1:0.6 to 1:2. In some embodiments, when the active layer comprises a mixture of PM6 and non-fullerene receptor Y6 or its derivatives, the weight ratio of PM6 to non-fullerene receptor Y6 or its derivatives in the mixture is 1:0.8 to 1:1.8, 1:1.0 to 1:1.6, or 1:1.2 to 1:1.4. In a specific implementation, when the active layer comprises a mixture of PM6 and non-fullerene receptor Y6 or its derivatives, the weight ratio of PM6 to non-fullerene receptor Y6 or its derivatives in the mixture is 1:0.6, 1:0.7, 1:0.8, 1:0.9, 1:1.0, 1:1.1, 1:1.2, 1:1.3, 1:1.4, 1:1.5, 1:1.6, 1:1.7, 1:1.8, 1:1.9, or 1:2.0.

[0113] In some implementations, the active layer comprises PM6 and PC 61 When BM is mixed with Y6, PM6 and PC 61 The weight ratio of BM to Y6 in the mixture is 1:0.02-0.4:0.6-2. In some embodiments, the active layer comprises PM6 and PC. 61 When BM is mixed with Y6, PM6 and PC 61 The weight ratio of BM to Y6 in the mixture is 1:0.04-0.35:0.6-2, 1:0.1-0.3:0.6-2, 1:0.15-0.25:0.6-2, 1:0.18-0.2:0.6-2, 1:0.02-0.4:0.8-1.8, 1:0.02-0.4:1.0-1.6, or 1:0.02-0.4:1.2-1.4.

[0114] Method for preparing the flexible transparent electrode

[0115] On the other hand, this application provides a method for preparing the flexible transparent electrode, comprising: dissolving an electrolyte in a solvent to form an electrolyte solution; adding the electrolyte solution to a suspension of conductive nanomaterials to form a dispersion in which the conductive nanomaterials are uniformly dispersed; pretreating the surface of a flexible transparent substrate; and coating the dispersion solution onto the flexible transparent substrate to form a conductive thin film on the flexible transparent substrate in which the conductive nanomaterials are distributed in a 0.1-1 μm × 0.1-1 μm grid-like structure, thereby obtaining the flexible transparent electrode.

[0116] In some embodiments, the concentration of the electrolyte is 0.1 to 1000 mg / mL, 0.5 to 800 mg / mL, 1 to 500 mg / mL, 2 to 300 mg / mL, 4 to 200 mg / mL, 10 to 100 mg / mL, or 20 to 50 mg / mL. In specific embodiments, the concentration of the electrolyte is 0.1 mg / mL, 0.4 mg / mL, 0.8 mg / mL, 2 mg / mL, 4 mg / mL, 8 mg / mL, 20 mg / mL, 40 mg / mL, 80 mg / mL, 200 mg / mL, 400 mg / mL, 600 mg / mL, 800 mg / mL, or 1000 mg / mL.

[0117] In some embodiments, the concentration of the dispersion of the conductive nanomaterial is 0.1 to 100 mg / mL, 0.2 to 80 mg / mL, 0.5 to 50 mg / mL, 1 to 30 mg / mL, 2 to 20 mg / mL, or 5 to 10 mg / mL. In specific embodiments, the concentration of the dispersion of the conductive nanomaterial is 0.1 mg / mL, 0.2 mg / mL, 0.4 mg / mL, 0.8 mg / mL, 12 mg / mL, 4 mg / mL, 8 mg / mL, 20 mg / mL, 40 mg / mL, 60 mg / mL, 80 mg / mL, or 100 mg / mL. In embodiments of this application, when the concentration of the dispersion of the conductive nanomaterial is 0.1 mg / mL to 100 mg / mL, the conductive nanomaterial tends to be horizontally oriented in the dispersion.

[0118] In some embodiments, the solvent is water, methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, tert-butanol, ethylene glycol, or any combination thereof. In a preferred embodiment, the solvent is water, methanol, ethanol, isopropanol, or any combination thereof.

[0119] In some embodiments, the coating includes dip coating, spin coating, LB film coating, blade coating, screen printing, inkjet printing, nanoimprinting, electrospinning, or slot coating.

[0120] In some embodiments, the conductive nanomaterials are uniformly dispersed in a dispersion in an ordered manner.

[0121] In some embodiments, the dip-coating method includes vertically immersing the horizontal or vertical axis of the flexible transparent substrate in the dispersion and allowing it to stand for 30 to 60 minutes, and then vertically immersing the vertical or horizontal axis of the flexible transparent substrate in the dispersion and allowing it to stand for 30 to 60 minutes. In specific embodiments, the standing times are independently 30 minutes, 40 minutes, 45 minutes, 50 minutes, 55 minutes, and 60 minutes.

[0122] In some embodiments, the spin coating method includes coating the dispersion at a rotation speed of 500 to 5000 rpm and then drying it at a temperature of 25-120°C for 1-60 min.

[0123] In some embodiments, the rotational speed is 800 to 4500 rpm, 1000 to 4000 rpm, 1500 to 3500 rpm, or 2000 to 3000 rpm. In specific embodiments, the rotational speed is 500 rpm, 600 rpm, 900 rpm, 1000 rpm, 1200 rpm, 1400 rpm, 1800 rpm, 2200 rpm, 2500 rpm, 2800 rpm, 3200 rpm, 3800 rpm, 4200 rpm, 4600 rpm, or 5000 rpm.

[0124] In some embodiments, the blade coating method involves applying the dispersion along the flexible transparent substrate and then drying it at a temperature of 25 to 120°C for 5 to 60 minutes.

[0125] In some embodiments, the screen printing method involves printing the dispersion onto the flexible transparent substrate and then drying it at a temperature of 25 to 120°C for 5 to 60 minutes.

[0126] In some embodiments, the slit coating involves applying the dispersion onto the flexible transparent substrate and then drying it at a temperature of 25 to 120°C for 5 to 60 minutes.

[0127] In some embodiments, the drying temperature is 25 to 120°C, 40 to 100°C, 50 to 90°C, or 60 to 80°C. In specific embodiments, the drying time is 25°C, 40°C, 55°C, 80°C, 90°C, 100°C, 110°C, or 120°C.

[0128] In some embodiments, the pretreatment includes ultrasonically cleaning the flexible transparent substrate sequentially with detergent, deionized water, and isopropanol at room temperature for 15 minutes each, removing it and drying it with nitrogen gas, and then treating it in an ultraviolet ozone cleaner for 20 minutes.

[0129] In some implementations, the mesh-like structure is a mesh-like structure formed by the intersection of silver lines.

[0130] In some embodiments, the weight ratio of the electrolyte to the conductive nanomaterial in the dispersion is 1:4 to 1:8.

[0131] In some embodiments, the pretreatment includes ultrasonically cleaning the flexible transparent substrate sequentially with detergent, deionized water, and isopropanol at room temperature for 15 minutes each, removing it and drying it with nitrogen gas, and then treating it in an ultraviolet ozone cleaner for 20 minutes.

[0132] Methods for preparing flexible organic solar cells

[0133] On the other hand, this application provides a method for preparing the flexible organic solar cell, comprising: providing a flexible transparent electrode; forming an electron transport layer on the flexible transparent electrode; forming an active layer on the electron transport layer; forming a hole transport layer on the active layer; and forming an anode layer on the hole transport layer, wherein the active layer comprises a mixture of PM6 and a non-fullerene acceptor Y6 or a derivative thereof, or PM6 and PC. 61 A mixture or combination of BM and Y6,

[0134]

[0135]

[0136] In PM6 and Y6, R is independently C1-C. 20 alkyl.

[0137] In some embodiments, non-limiting examples of R are selected from methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, isobutyl, 2-ethylbutyl, 3,3-dimethylbutyl, n-pentyl, isopentyl, neopentyl, tert-pentyl, 1-methylpentyl, 3-methylpentyl, 2-ethylpentyl, 4-methyl-2-pentyl, n-hexyl, 1-methylhexyl, 2-ethylhexyl, 2-butylhexyl, n-heptyl, 1-methylheptyl, 2,2-dimethylheptyl, 2-ethylheptyl, 2-butylheptyl, n-octyl, tert-octyl, 2-Ethyloctyl, 2-Butyloctyl, 2-Hexyloctyl, 3,7-Dimethyloctyl, n-Nonyl, n-Decyl, 2-Ethyldecyl, 2-Butyldecyl, 2-Hexyldecyl, 2-Ocyldecyl, n-Undecyl, n-Dodecyl, 2-Ethyldodecyl, 2-Butyldodecyl, 2-Hexyldodecyl, 2-Ocyldodecyl, n-Tridecyl, n-Tetradecyl, n-Pentadecanyl, n-Hexadecyl, 2-Ethylhexadecyl, 2-Butylhexadecyl, n-Heptadecanyl, n-Octadecanyl, n-Nondecyl, n-Eicosyl, etc.

[0138] In a preferred embodiment, R is selected from methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, isobutyl, 2-ethylbutyl, 3,3-dimethylbutyl, n-pentyl, isopentyl, neopentyl, tert-pentyl, 1-methylpentyl, 3-methylpentyl, 2-ethylpentyl, 4-methyl-2-pentyl, n-hexyl, 1-methylhexyl, 2-ethylhexyl, 2-butylhexyl, n-heptyl, 1-methylheptyl, 2,2-dimethylheptyl, 2-ethylheptyl, 2-butylheptyl, n-octyl, tert-octyl, 2-ethyloctyl, 2-butyloctyl, 2-hexyloctyl, 3,7-dimethyloctyl, n-nonyl, n-decyl, 2-ethyldecyl, 2-butyldecyl, or 2-hexyldecyl.

[0139] In a more preferred embodiment, R is selected from methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, isobutyl, 2-ethylbutyl, 1-methylpentyl, 2-ethylpentyl, n-hexyl, 1-methylhexyl, 2-ethylhexyl, 2-butylhexyl, 2-ethylheptyl, 2-butylheptyl, n-octyl, tert-octyl, 2-ethyloctyl, 2-butyloctyl, or 2-hexyloctyl. In the most preferred embodiment, R is selected from 2-ethylbutyl, 2-ethylhexyl, 2-ethylpentyl, 2-ethyloctyl, or 2-butyloctyl.

[0140] In some embodiments, providing a flexible transparent electrode includes forming a conductive thin film on a flexible transparent substrate.

[0141] In some embodiments, forming the electron transport layer includes coating the flexible transparent electrode with any one or any combination of ZnO, TiO2, or SnO2 nanoparticle dispersions.

[0142] In some embodiments, forming the active layer comprises mixing PM6 with a non-fullerene receptor Y6 or a derivative thereof; or, PM6 and PC 61 The mixture of BM and Y6 is coated onto the electron transport layer in solution form.

[0143] In some embodiments, forming the hole transport layer includes depositing any one or any combination of MoO3, V2O5, or WO3 onto the active layer.

[0144] In some embodiments, forming the anode layer includes depositing any one or any combination of silver, gold, or aluminum onto the hole transport layer.

[0145] In other embodiments, the method further includes forming an interface modification layer between the electron transport layer and the active layer. In some embodiments, forming the interface modification layer includes coating a conductive polymer PFN-Br or a PFN solution or a combination thereof between the electron transport layer and the active layer.

[0146] In some embodiments, the conductive polymer is any one of PFN-Br or PFN or a combination thereof.

[0147] In some embodiments, the coating includes spin coating, blade coating, LB film coating, screen printing, inkjet printing, nanoimprinting, electrospinning, or slot coating.

[0148] In some embodiments, when the active layer comprises a mixture of PM6 and non-fullerene receptor Y6 or its derivatives, the weight ratio of PM6 to non-fullerene receptor Y6 or its derivatives in the mixture is 1:0.6 to 1:2. In some embodiments, when the active layer comprises a mixture of PM6 and non-fullerene receptor Y6 or its derivatives, the weight ratio of PM6 to non-fullerene receptor Y6 or its derivatives in the mixture is 1:0.8 to 1:1.8, 1:1.0 to 1:1.6, or 1:1.2 to 1:1.4. In a specific implementation, when the active layer comprises a mixture of PM6 and non-fullerene receptor Y6 or its derivatives, the weight ratio of PM6 to non-fullerene receptor Y6 or its derivatives in the mixture is 1:0.6, 1:0.7, 1:0.8, 1:0.9, 1:1.0, 1:1.1, 1:1.2, 1:1.3, 1:1.4, 1:1.5, 1:1.6, 1:1.7, 1:1.8, 1:1.9, or 1:2.0.

[0149] In some implementations, the active layer comprises PM6 and PC 61 When BM is mixed with Y6, PM6 and PC 61 The weight ratio of BM to Y6 in the mixture is 1:0.02-0.4:0.6-2. In some embodiments, the active layer comprises PM6 and PC. 61 When BM is mixed with Y6, PM6 and PC 61 The weight ratio of BM to Y6 in the mixture is 1:0.04-0.35:0.6-2, 1:0.1-0.3:0.6-2, 1:0.15-0.25:0.6-2, 1:0.18-0.2:0.6-2, 1:0.02-0.4:0.8-1.8, 1:0.02-0.4:1.0-1.6, or 1:0.02-0.4:1.2-1.4. In some embodiments, the active layer comprises PM6 and PC. 61 When BM is mixed with Y6, PM6 and PC 61The weight ratio of BM to Y6 in the mixture is 1:0.04:0.6, 1:0.08:0.6, 1:0.1:0.6, 1:0.2:0.6, 1:0.3:0.6, 1:0.4:0.6, 1:0.04:0.8, 1:0.08:0.8, 1:0.1:0.8, 1:0.2:0.8, 1:0.3:0.8, 1:0.4:0.8, 1:0.04:1, 1:0.08:1, 1:0.1:1, 1:0.2:1, 1:0.3: 1, 1:0.4:1, 1:0.04:1.2, 1:0.08:1.2, 1:0.1:1.2, 1:0.2:1.2, 1:0.3:1.2, 1:0.4:1.2, 1:0.04:1.5, 1:0.08:1.5, 1:0.1:1.5, 1:0.2:1.5, 1:0.3:1.5, 1:0.4:1.5, 1:0.04:2, 1:0.08:2, 1:0.1:2, 1:0.2:2, 1:0.3:2, 1:0.4 :2, 1:0.04:0.6, 1:0.04:0.8, 1:0.04:1.0, 1:0.04:1.2, 1:0.04:1.5, 1:0.04:2, 1:0.08:0.6, 1:0.08:0.8, 1:0.08:1.0, 1:0.08:1.2, 1:0.08:1.5, 1:0.08:2, 1:0.1:0.6, 1:0.1:0.8, 1:0.1:1.0, 1:0.1:1.2, 1:0.1:1.5, 1:0.1:2, 1:0.2:0.6, 1:0.2:0.8, 1:0.2:1.0, 1:0.2:1.2, 1:0.2:1.5, 1:0.2:2, 1:0.3:0.6, 1:0.3:0.8, 1:0.3:1.0, 1:0.3:1.2, 1:0.3:1.5, 1:0.3:2, 1:0.4:0.6, 1:0.4:0.8, 1:0.4:1.0, 1:0.4:1.2, 1:0.4:1.5 or 1:0.4:2.

[0150] Beneficial effects of the invention

[0151] This application achieves an open-circuit voltage of 0.80-0.90V and a short-circuit current density of 24-30mA / cm by using flexible transparent electrodes. 2 This application describes a flexible organic solar cell with a fill factor of 70%-80% and an energy conversion efficiency of 15%-18%. Furthermore, the flexible transparent electrode of this application exhibits high energy conversion efficiency and high stability.

[0152] Example

[0153] The following embodiments describe this application in more detail, but are not intended to limit the scope of this application.

[0154] Fabrication of flexible transparent electrodes

[0155] A 2cm×2cm (length×width) flexible polyethylene terephthalate (PET) substrate was sequentially ultrasonically cleaned with dish soap, deionized water, and isopropanol at room temperature for 15 minutes, dried with nitrogen, and then treated in a UV ozone cleaner for 20 minutes to obtain a pretreated flexible polyethylene terephthalate substrate.

[0156] A flexible transparent electrode was obtained by spin-coating 100 μL of a 5 mg / mL silver nanowire dispersion onto the surface of the pretreated polyethylene terephthalate flexible substrate using a spin coater at a speed of 1000 rpm for 60 s.

[0157] Fabrication of flexible organic solar cells

[0158] Example 1

[0159] A methanol solution of 10 mg / mL ZnO nanoparticles was spin-coated onto a flexible transparent electrode to form an electron transport layer with a thickness of approximately 20 nm. A methanol solution of 1 mg / mL PFN-Br was then spin-coated onto the electron transport layer to form an interface modification layer with a thickness of approximately 10 nm. PM6 (where R is 2-ethylhexyl) and Y6 (where R is 2-butyloctyl) were added to chloroform at a mass ratio of 1:1.2 to form a donor concentration of 7 mg / mL. -1 A solution was prepared, and then 1,8-diiodooctane was added so that the volume fraction of 1,8-diiodooctane was 0.5% of chloroform. The above solution was spin-coated onto the interface modification layer to obtain an active layer with a thickness of approximately 140 nm. The above-treated flexible transparent electrode was placed at a depth of less than 2 × 10⁻⁶. -4 In a vacuum chamber with a pressure of Pa, MoO3 is deposited onto the active layer to form a hole transport layer with a thickness of approximately 6 nm. The flexible transparent electrode with the deposited hole transport layer is then placed in a vacuum chamber with a pressure of less than 2 × 10⁻⁶ Pa. -4 In a vacuum chamber of Pa, silver is deposited onto the hole transport layer to form an anode layer with a thickness of approximately 70 nm, thereby obtaining a flexible organic solar cell. The obtained flexible organic solar cell is then subjected to standard sunlight (AM 1.5G, 100mW cm⁻¹). -2 The current density-voltage curve was measured under irradiation conditions.

[0160] The flexible organic solar cell has an open-circuit voltage of 0.837V and a short-circuit current density of 24.92mA / cm². -2 The fill factor is 74.8%, and the energy conversion efficiency is 15.60%.

[0161] The stability of the flexible organic solar cell was tested by placing it in an argon-protected glove box. After being placed in the glove box at room temperature for 185 days, the flexible organic solar cell still retained 95.1% of its initial performance.

[0162] Example 2

[0163] A methanol solution of 10 mg / mL ZnO nanoparticles was spin-coated onto a flexible transparent electrode to form an electron transport layer with a thickness of approximately 20 nm. A methanol solution of 1 mg / mL PFN-Br was then spin-coated onto the electron transport layer to form an interface modification layer with a thickness of approximately 10 nm. PM6 (where R is 2-ethylhexyl), Y6 (where R is 2-ethylhexyl), and PC were then used as the interface modification layer. 61 BM was added to chloroform at a mass ratio of 1:1.2:0.2 to form a donor concentration of 7 mg / mL. -1 A solution was prepared, and then chloronaphthalene was added so that the volume fraction of chloronaphthalene was 0.8% of chloroform. The above solution was spin-coated onto the interface modification layer, and then heated at 100°C for 10 min to obtain an active layer with a thickness of approximately 150 nm. The flexible transparent electrode treated as described above was placed in a container below 2 × 10⁻⁶ m² / h. -4 In a vacuum chamber with a pressure of Pa, MoO3 is deposited onto the active layer to form a hole transport layer with a thickness of approximately 6 nm. The flexible transparent electrode with the deposited hole transport layer is then placed in a vacuum chamber with a pressure of less than 2 × 10⁻⁶ Pa. -4 In a vacuum chamber of Pa, silver is deposited onto the hole transport layer to form an anode layer with a thickness of approximately 70 nm, thereby creating a flexible organic solar cell. The obtained flexible organic solar cell is then subjected to standard sunlight (AM 1.5G, 100mW cm⁻¹). -2 The current density-voltage curve was measured under irradiation conditions.

[0164] The flexible organic solar cell has an open-circuit voltage of 0.837V and a short-circuit current density of 24.70mA / cm². -2 The fill factor is 74.5%, and the energy conversion efficiency is 15.40%.

[0165] The stability of the above-mentioned device was tested by placing it in an argon-protected glove box. After being placed in the glove box at room temperature for 173 days, the flexible organic solar cell still retained 96.4% of its initial performance.

[0166] Example 3

[0167] A methanol solution of 10 mg / mL ZnO nanoparticles was spin-coated onto a flexible transparent electrode to form an electron transport layer with a thickness of approximately 20 nm. A methanol solution of 1 mg / mL PFN-Br was then spin-coated onto the electron transport layer to form an interface modification layer with a thickness of approximately 10 nm. PM6 (where R is 2-ethylhexyl) and Y6 (where R is 2-ethylhexyl) were added to chloroform at a mass ratio of 1:1.2 to form a donor concentration of 7 mg / mL. -1 A solution was prepared, and then chloronaphthalene was added so that the volume fraction of chloronaphthalene was 0.5% of chloroform. The solution was spin-coated onto the interface modification layer, and then heated at 100°C for 10 min to obtain an active layer with a thickness of approximately 110 nm. The flexible transparent electrode treated as described above was placed in a container below 2 × 10⁻⁶ m² / h. -4 In a vacuum chamber with a pressure of Pa, MoO3 is deposited onto the active layer to form a hole transport layer with a thickness of approximately 6 nm. The flexible transparent electrode with the deposited hole transport layer is then placed in a vacuum chamber with a pressure of less than 2 × 10⁻⁶ Pa. -4 In a vacuum chamber of Pa, silver is deposited onto the hole transport layer to form an anode layer with a thickness of approximately 70 nm, thereby creating a flexible organic solar cell. The obtained flexible organic solar cell is then subjected to standard sunlight (AM 1.5G, 100mW cm⁻¹). -2 The current density-voltage curve was measured under irradiation conditions.

[0168] The flexible organic solar cell has an open-circuit voltage of 0.829V and a short-circuit current density of 24.87mA / cm². -2 The fill factor is 74.3%, and the energy conversion efficiency is 15.32%.

[0169] The stability of the above-mentioned device was tested by placing it in an argon-protected glove box. After being placed in the glove box at room temperature for 177 days, the flexible organic solar cell still retained 95.3% of its initial performance.

[0170] Comparative Example 4

[0171] Rigid organic solar cells were fabricated in the same manner as in Example 1, but commercially available ITO glass was used instead of the flexible transparent electrode of this application.

[0172] The obtained rigid organic solar cell has an open-circuit voltage of 0.837V and a short-circuit current density of 25.60mA / cm². -2 The fill factor is 74.7%, and the energy conversion efficiency reaches 16.01%.

[0173] The stability of the above-mentioned device was tested by placing it in an argon-protected glove box. After being placed in the glove box at room temperature for 185 days, the rigid organic solar cell still retained 95.3% of its initial performance.

[0174] Comparative Example 5

[0175] Rigid organic solar cells were prepared in the same manner as in Example 2, but commercially available ITO glass was used instead of the flexible transparent electrode of this application.

[0176] The obtained rigid organic solar cell has an open-circuit voltage of 0.837V and a short-circuit current density of 25.54mA / cm². -2 The fill factor is 74.8%, and the energy conversion efficiency reaches 15.99%.

[0177] The stability of the above-mentioned device was tested by placing it in an argon-protected glove box. After being placed in the glove box at room temperature for 173 days, the rigid organic solar cell still retained 96.7% of its initial performance.

[0178] Comparative Example 6

[0179] Rigid organic solar cells were prepared in the same manner as in Example 3, but commercially available ITO glass was used instead of the flexible transparent electrode of this application.

[0180] The obtained rigid organic solar cell has an open-circuit voltage of 0.829 V and a short-circuit current density of 25.43 mA / cm². -2 The fill factor is 74.5%, and the energy conversion efficiency reaches 15.71%.

[0181] The stability of the above-mentioned device was tested by placing it in an argon-protected glove box. After being placed in the glove box at room temperature for 177 days, the rigid organic solar cell still retained 95.4% of its initial performance.

[0182] Figure 3 The current density-voltage curves of flexible organic solar cells and rigid organic solar cells are shown. The results in the figure demonstrate that the performance of the flexible organic solar cell fabricated using the flexible transparent electrode of this application is comparable to that of a rigid organic solar cell fabricated using commercial ITO.

[0183] Figure 4 The stability of flexible and rigid organic solar cells is shown. The results in the figure demonstrate that the stability of the flexible organic solar cell fabricated using the flexible transparent electrode of this application is comparable to that of the rigid organic solar cell fabricated using commercial ITO.

Claims

1. Flexible organic solar cells, including: Flexible transparent electrode; An electron transport layer, wherein the electron transport layer comprises ZnO nanoparticles; Active layer; Hole transport layer, the hole transport layer comprising MoO3; and Anode layer, the anode layer comprising silver, The active layer comprises a mixture of PM6 and non-fullerene receptor Y6; or, PM6 and PC 61 A mixture of BM and Y6; or a combination thereof, ， In PM6 and Y6, R is independently C1-C. 20 alkyl; The flexible organic solar cell further includes an interface modification layer, which is located between the electron transport layer and the active layer, and the interface modification layer includes a conductive polymer PFN-Br. The flexible transparent electrode includes: A flexible transparent substrate, wherein the flexible transparent substrate is selected from polyethylene terephthalate, polyethersulfone resin, polyethylene naphthalate, polycarbonate, polyimide, hexamethylene polypropylene, polyethylene, parylene, polydimethylsiloxane, or combinations thereof; and A conductive thin film disposed on the surface of the flexible transparent substrate, the conductive thin film comprising silver nanowires.

2. The flexible organic solar cell according to claim 1, wherein the conductive film has a thickness of 30 nm to 1 μm and a surface roughness Ra of 5 to 10 nm.

3. The flexible organic solar cell according to claim 1 or 2, wherein the conductive film comprises an electrolyte and conductive nanomaterials in a weight ratio of 1:4 to 1:8, and the conductive nanomaterials include the silver nanowires.

4. The flexible organic solar cell according to claim 3, wherein the electrolyte is a cationic electrolyte or an anionic electrolyte.

5. The flexible organic solar cell according to claim 3, wherein the conductive nanomaterial is nanowires and is distributed in the conductive film in a mesh-like structure, and the nanowires include the silver nanowires.

6. The flexible organic solar cell of claim 3, wherein the conductive nanomaterial has a diameter of 10 to 100 nm and a length of 15 to 35 μm.

7. The flexible organic solar cell of claim 1, wherein the electron transport layer further comprises any one or any combination of TiO2 or SnO2 nanoparticles.

8. The flexible organic solar cell of claim 1, wherein the hole transport layer further comprises any one or any combination of V2O5 or WO3.

9. The flexible organic solar cell of claim 1, wherein the anode layer further comprises any one or any combination of gold or aluminum.

10. The flexible organic solar cell of claim 1, wherein when the active layer comprises a mixture of PM6 and non-fullerene acceptor Y6, the weight ratio of PM6 to non-fullerene acceptor Y6 in the mixture is from 1:0.6 to 1:

2.

11. The flexible organic solar cell according to claim 1 or 10, wherein the non-fullerene acceptor Y6 is one of the following compounds: or .

12. The flexible organic solar cell of claim 1, wherein the active layer comprises PM6 and PC. 61 When BM is mixed with Y6, PM6 and PC 61 The weight ratio of BM to Y6 in the mixture is 1 : 0.02-0.4 : 0.6-2.

13. A method for preparing flexible organic solar cells, comprising: Provide flexible transparent electrodes; An electron transport layer is formed on the flexible transparent electrode, and the electron transport layer includes ZnO nanoparticles; An active layer is formed on the electron transport layer; A hole transport layer is formed on the active layer, the hole transport layer comprising MoO3; and An anode layer is formed on the hole transport layer, the anode layer comprising silver. The active layer comprises a mixture of PM6 and non-fullerene receptor Y6; or, PM6 and PC. 61 A mixture of BM and Y6; or a combination thereof, ， In PM6 and Y6, R is independently C1-C. 20 alkyl; The provision of the flexible transparent electrode includes forming a conductive film on a flexible transparent substrate, the flexible transparent substrate being selected from polyethylene terephthalate, polyethersulfone resin, polyethylene naphthalate, polycarbonate, polyimide, hexamethylene polypropylene, polyethylene, parylene, polydimethylsiloxane, or combinations thereof; and the conductive film comprising silver nanowires; The method further includes forming an interface modification layer between the electron transport layer and the active layer, the interface modification layer comprising a conductive polymer PFN-Br.

14. The method of claim 13, wherein: The formation of the electron transport layer includes coating the flexible transparent electrode with a ZnO nanoparticle dispersion. The formation of the active layer includes coating the electron transport layer with a mixture of PM6 and non-fullerene acceptor Y6 in solution form; Alternatively, PM6 and PC 61 A mixture of BM and Y6 is coated onto the electron transport layer in solution form; The formation of the hole transport layer includes depositing MoO3 onto the active layer; and The formation of the anode layer includes depositing silver onto the hole transport layer by vapor deposition.

15. The method of claim 14, wherein: The ZnO nanoparticle dispersion also includes any one or any combination of TiO2 or SnO2 nanoparticles. The formation of the hole transport layer also includes vapor deposition of any one or any combination of V2O5 or WO3 onto the active layer. The formation of the anode layer also includes depositing any one or any combination of gold or aluminum onto the hole transport layer.

16. The method of any one of claims 13 to 15, wherein forming the interface modification layer comprises coating a conductive polymer PFN-Br solution between the electron transport layer and the active layer.

17. The method of claim 13, wherein when the active layer comprises a mixture of PM6 and non-fullerene receptor Y6, the weight ratio of PM6 to non-fullerene receptor Y6 in the mixture is from 1:0.6 to 1:

2.

18. The method of claim 13 or 17, wherein the non-fullerene receptor Y6 is a compound of the following composition: or .

19. The method of claim 13, wherein the active layer comprises PM6 and PC. 61 When BM is mixed with Y6, PM6 and PC 61 The weight ratio of BM to Y6 in the mixture is 1 : 0.02-0.4 : 0.6-2.

Images