Selective charge transport layer, precursor solution, perovskite battery, preparation method therefor, and electric apparatus

Abstract

The present disclosure relates to the technical field of solar cells and discloses a selective charge transport layer, a precursor solution, a perovskite battery, a preparation method therefor, and an electric apparatus. The selective charge transport layer of the present disclosure is adapted for a solar cell and comprises a high-molecular polymer serving as a parent material, a selective charge transport polymer doped in the parent material, and / or a copolymer formed by the high-molecular polymer and the selective charge transport polymer; wherein the selective charge transport polymer transports electrons or holes; and the molecular weight of the high-molecular polymer is greater than 10,000. The selective charge transport layer, the perovskite battery, and the preparation method therefor provided by the present disclosure allow for a reduction in the amount of the selective charge transport layer material used while ensuring the transporting effect of the selective charge transport layer.

Description

Selective charge transport layer, precursor liquid, perovskite battery, preparation method thereof, and power-using device

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This disclosure claims priority to application number 2024103619943 filed with the China Patent Office on March 27, 2024, entitled “Selective charge transport layer, precursor liquid, perovskite battery and preparation method thereof,” the entire contents of which are incorporated by reference into this disclosure. Technical Field

[0003] The present disclosure relates to the technical field of solar cells, and in particular to a selective charge transport layer, a precursor liquid, a perovskite cell, a preparation method thereof, and an electrical device thereof. Background Art

[0004] Since its invention in 2009, perovskite solar cells have seen rapid efficiency improvements, demonstrating the enormous potential of next-generation commercial solar cells. Perovskite solar cells typically consist of five components: transparent conductive glass, an electron transport layer, a perovskite light-absorbing layer, a hole transport layer, and a metal back electrode. The hole transport layer, typically 0-150nm thick, collects holes injected from the perovskite light-absorbing layer and separates the charge of electron-hole pairs in the perovskite light-absorbing layer. Perovskite solar cells without a hole transport layer typically have relatively low photoelectric conversion efficiency. Inserting a hole transport material between the perovskite light-absorbing layer and the metal back electrode can improve the Schottky contact, promote the separation of electrons and holes at the interface of the functional layer, reduce charge recombination, and adjust energy level matching, contributing to higher photoelectric conversion efficiency.

[0005] In 2012, 2,2′,7,7′-tetrakis[N,N-di(4-methoxyphenyl)amino]-9,9′-spirobifluorene (spiro-OMeTAD) was first used as a hole transport material in perovskite solar cells, achieving high photoelectric conversion efficiency. Currently, newly developed hole transport materials are often compared with spiro-OMeTAD. Although spiro-OMeTAD can achieve high photoelectric conversion efficiency as a hole transport material, its high unit price makes the selective charge transport layer of perovskite solar cells expensive, limiting the commercial application of perovskite solar cells. Summary of the Invention

[0006] The purpose of the present disclosure is to provide a selective charge transport layer, a perovskite cell, a preparation method thereof, and an electrical device, which can reduce the amount of selective charge transport layer material while ensuring the transport effect of the selective charge transport layer, thereby achieving the purpose of significantly reducing the cost of the selective charge transport layer.

[0007] On the one hand, an embodiment of the present disclosure provides a selective charge transport layer, which is used for a solar cell and includes a high molecular weight polymer as a matrix material, a selective charge transport polymer doped in the matrix material, and / or a copolymer formed by the high molecular weight polymer and the selective charge transport polymer; wherein the selective charge transport polymer transports electrons or holes; and the molecular weight of the high molecular weight polymer is greater than 10,000.

[0008] As an practicable manner, the mass ratio of the high molecular weight polymer to the selective charge transport polymer is between 1:4 and 4:1. In a preferred embodiment, the mass ratio of the high molecular weight polymer to the selective charge transport polymer is between 2:3 and 3:2.

[0009] As an practicable manner, the high molecular polymer is one or more combinations of cross-linked polydimethylsiloxane, polymethyl methacrylate, polyvinyl pyrrolidone, poly-4-ethylphenol, polybutylene terephthalate, polystyrene, polyvinyl chloride, polypropylene, polyethylene, polylactic acid, polyformaldehyde, polyamide, polyimide, polyethyleneimine, polydopamine, polyvinylidene fluoride, polyacrylonitrile, or one or more copolymers.

[0010] As an illustrative embodiment, the selective charge transport polymer is a polymer hole transport material used in the hole transport layer.

[0011] As an practicable manner, the polymer hole transport material is a combination of one or more of PTAA, Poly-TPD, P3HT, PEDOT, EDOT:PSS, PANI, or a derivative of one or more thereof;

[0012] As an illustrative embodiment, the selective charge transport polymer is a polymer electron transport material used in the electron transport layer.

[0013] As an practicable manner, the polymer electron transport material includes a combination of one or more of N2200, N2300, N-CS2DPP-OD-TEG, P-BNBP-T, and P-IFDMT4, or a derivative of one or more of the foregoing.

[0014] As an practicable approach, the high molecular weight polymer contains a coordination group for passivating defects in the perovskite film; optionally, the coordination group includes one or more of an amino group, a carboxyl group, a hydroxyl group, a benzene ring, and a sulfonic acid group.

[0015] As an practicable manner, the selective charge transport layer is further doped with an additive for improving carrier mobility. The additive may include at least one of Li-TFSI and Tbp.

[0016] Another aspect of the embodiments of the present disclosure provides a precursor liquid for preparing a selective charge transport layer, comprising a polymer, a selective charge transport polymer, and / or a copolymer formed by the polymer and the selective charge transport polymer, and a solvent, wherein the selective charge transport polymer utilizes electrons or holes to transport charges; and the molecular weight of the polymer is greater than 10,000.

[0017] As an practicable manner, the mass ratio of the high molecular weight polymer to the selective charge transport polymer is between 1:4 and 9:1. In a preferred embodiment, the mass ratio of the high molecular weight polymer to the selective charge transport polymer is between 2:3 and 3:2.

[0018] As an practicable manner, the high molecular polymer is a combination of one or more of cross-linked polydimethylsiloxane, polymethyl methacrylate, polyvinyl pyrrolidone, poly-4-ethylphenol, polybutylene terephthalate, polystyrene, polyvinyl chloride, polypropylene, polyethylene, polyvinyl alcohol, polylactic acid, polycarbonate, polyacrylic acid, plastic starch material, polysulfone, polyurethane, polyformaldehyde, polyamide, polyimide, polyamideimide, polyethyleneimine, polydopamine, polyvinylidene fluoride, polyacrylonitrile, polyetheretherketone, epoxy resin and ABS resin, or one or more copolymers.

[0019] As an practicable manner, the precursor liquid includes Poly-TPD, PMMA and PTAA, and the mass concentration ratio of the three is 3:4:3.

[0020] According to another aspect of the embodiments of the present disclosure, a perovskite battery is provided, comprising a perovskite film layer and any one of the selective charge transport layers described above.

[0021] Another aspect of the embodiments of the present disclosure provides a method for preparing a perovskite battery, including a preparation process for a selective charge transport layer, the preparation process for the selective charge transport layer comprising: coating a substrate with a precursor liquid of the selective charge transport layer described in any one of the above items to form a selective charge transport layer, the selective charge transport layer comprising a high molecular weight polymer as a matrix material, and a selective charge transport polymer doped in the matrix material, and / or a copolymer formed by the high molecular weight polymer and the selective charge transport polymer.

[0022] The beneficial effects of the embodiments of the present disclosure include:

[0023] The present disclosure provides a selective charge transport layer for use in a solar cell, comprising a polymer as a matrix material, a selective charge transport polymer doped in the matrix material, and / or a copolymer formed by the polymer and the selective charge transport polymer. The polymer has a molecular weight greater than 10,000. When the polymer is used as the matrix material, the amount of the selective charge transport polymer used can be reduced while increasing the coating properties of the material to facilitate film formation. Therefore, the present disclosure reduces the amount of the selective polymer used without affecting (or substantially affecting) the function of the selective charge transport layer.

[0024] The selective charge transport polymers used in existing perovskite cells are expensive (18K / g), while the price of high-molecular-weight polymers is significantly lower than that of selective charge transport polymers, making their cost essentially negligible. Therefore, reducing the amount of selective charge transport polymers used significantly reduces the cost of the selective charge transport layer. If the disclosed solution is applied to perovskite cells, the cost of the hole transport layer alone could be reduced by 50%.

[0025] In addition, for perovskite batteries, adding high molecular weight polymers to the selective charge transport layer can also improve the wettability of the perovskite solution relative to the selective charge transport layer. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present disclosure and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without creative work.

[0027] FIG1 is a schematic diagram of a structure of a perovskite battery provided by an embodiment of the present disclosure;

[0028] FIG2 is a flow chart of a method for preparing a perovskite battery according to an embodiment of the present disclosure;

[0029] FIG3 is a second structural schematic diagram of a perovskite battery provided by an embodiment of the present disclosure;

[0030] FIG4 is a second flow chart of a method for preparing a perovskite battery according to an embodiment of the present disclosure;

[0031] FIG5 is a third structural schematic diagram of a perovskite battery provided by an embodiment of the present disclosure;

[0032] FIG6 is one of the performance comparison diagrams of multiple embodiments provided in the embodiment of the present disclosure;

[0033] FIG7 is a second performance comparison diagram of multiple embodiments provided in the embodiment of the present disclosure;

[0034] FIG8 is a third performance comparison diagram of multiple embodiments provided in the embodiment of the present disclosure;

[0035] FIG9 is a fourth performance comparison diagram of multiple embodiments provided in the embodiment of the present disclosure;

[0036] FIG10 is a diagram showing the wettability contact angle test of the comparative example;

[0037] FIG11 is a wettability contact angle test diagram of an embodiment of the present disclosure.

[0038] Icons: 10-perovskite cell; 11-perovskite film layer; 12-hole transport layer; 13-electron transport layer; 14-crystalline silicon bottom cell; 16-electrode; 17-transparent conductive layer. DETAILED DESCRIPTION

[0039] To make the objectives, technical solutions, and advantages of the embodiments of the present disclosure more clear, the technical solutions of the embodiments of the present disclosure will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present disclosure. Obviously, the described embodiments are only some of the embodiments of the present disclosure, but not all of them. Generally, the components of the embodiments of the present disclosure described and shown in the drawings herein can be arranged and designed in various different configurations.

[0040] Therefore, the following detailed description of the embodiments of the present disclosure provided in the accompanying drawings is not intended to limit the scope of the present disclosure as claimed, but merely represents selected embodiments of the present disclosure. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present disclosure without creative effort shall fall within the scope of protection of the present disclosure.

[0041] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not require further definition or explanation in subsequent drawings.

[0042] Selective charge transport layer: The selective charge transport layer can selectively transport electrons or holes. The selective charge transport layer includes a hole transport layer and an electron transport layer, and is a basic functional layer in solar cells.

[0043] For example, for perovskite solar cells, the hole transport layer (HTL) is typically made of polymer materials, typically PTAA, Poly-TPD, P3HT, or PEDOT:PSS. However, the high cost of preparing these polymers is a significant constraint on their industrial application. Polymerization of these polymers is challenging, making it difficult to achieve a high degree of polymerization. A higher degree of polymerization allows for better substrate coverage during wet processing, helping the cell resist short-circuit channels.

[0044] To solve the above problems, an embodiment of the present disclosure provides a selective charge transport layer, which is used for solar cells and includes a high molecular polymer as a matrix material and a selective charge transport polymer doped in the matrix material, wherein the selective charge transport polymer transports electrons or holes; the molecular weight of the high molecular polymer is greater than 10,000.

[0045] In another embodiment, a selective charge transport layer is provided, comprising a high molecular weight polymer as a matrix material, a selective charge transport polymer doped in the matrix material, and a copolymer formed by the high molecular weight polymer and the selective charge transport polymer; wherein the selective charge transport polymer transports electrons or holes; and the molecular weight of the high molecular weight polymer is greater than 10,000.

[0046] In another embodiment, a selective charge transport layer is provided, comprising a copolymer formed by a high molecular weight polymer and a selective charge transport polymer; wherein the portion of the copolymer corresponding to the selective charge transport polymer transports electrons or holes; and the molecular weight of the high molecular weight polymer is greater than 10,000.

[0047] In another embodiment, a selective charge transport layer is provided, comprising a polymer and a copolymer formed by the polymer and the selective charge transport polymer; wherein the portion of the copolymer corresponding to the selective charge transport polymer transports electrons or holes; and the molecular weight of the polymer is greater than 10,000.

[0048] The above-mentioned selective charge transport layer refers to the hole transport layer or electron transport layer in the solar cell. Selective charge transport polymer refers to a polymer material that can be used as a hole transport layer or an electron transport layer, which has been disclosed or not disclosed so far. In the present disclosure, the polymer material that can be used as a hole transport layer is also referred to as a polymer hole transport material; the polymer material that can be used as an electron transport layer is also referred to as a polymer electron transport material. In summary, the polymer hole transport material (or polymer electron transport material) in the present disclosure can exist independently of the polymer, or exist in the form of a copolymer formed with the polymer, or both forms can exist at the same time.

[0049] The selective charge transport layer provided in the embodiment of the present disclosure can be used in a perovskite cell 10. Specifically, as shown in FIG1 , the perovskite cell 10 includes a perovskite film layer 11 and a hole transport layer 12 and an electron transport layer 13 arranged on both sides of the perovskite film layer 11. When the perovskite film layer 11 is irradiated by sunlight, the material in the perovskite film layer 11 absorbs photons to generate electron-hole pairs. The electron-hole pairs are separated into electrons and holes in the perovskite film layer 11. The electrons are collected by the electron transport layer 13, and the holes are collected by the hole transport layer 12, thereby realizing the conversion of light energy into electrical energy.

[0050] Specifically, the selective charge transport layer of the embodiment of the present disclosure selectively transports electrons or holes, that is, the selective charge transport layer provided by the embodiment of the present disclosure can be the electron transport layer 13 or the hole transport layer 12 of the perovskite battery 10. The solution of the present disclosure can be used for the electron transport layer of a perovskite battery, and can also be used for the hole transport layer of a perovskite battery, or can be used for both the electron transport layer and the hole transport layer of a perovskite battery. Perovskite batteries refer to single-junction or multi-junction batteries that include a perovskite film layer as a light absorption layer. In this article, perovskite batteries include at least: perovskite single-junction batteries, perovskite crystalline silicon stacked batteries, full perovskite stacked batteries, and other batteries that include at least one perovskite film layer as a light absorption layer.

[0051] Experimental data demonstrates that the transfer efficiency of the selective charge transport layer comprising a polymer provided by the present disclosure does not decrease. Furthermore, the selective charge transport layer comprising a polymer reduces the amount of the selective charge transport polymer used. Therefore, the selective charge transport layer of the present disclosure can reduce the amount of the selective charge transport polymer used while maintaining transfer efficiency. The selective charge transport polymer costs around 18,000 yuan per gram, while the cost of the polymer is relatively negligible. Reducing the amount of the selective charge transport polymer significantly reduces the cost of the selective charge transport layer.

[0052] Furthermore, the molecular weight of the high molecular weight polymer is greater than 10,000. High molecular weight polymers are readily available and relatively easy to prepare. When the selective charge transport layer comprises a high molecular weight polymer, the coating performance of the material is enhanced, and the molecular weight requirement for the selective charge transport polymer is reduced. This can, to a certain extent, reduce the difficulty of preparing the selective charge transport polymer (larger molecular weights generally increase the synthesis difficulty).

[0053] In summary, by adopting the disclosed solution, since a high molecular weight polymer is added to the raw materials for preparing the selective charge transport layer, the dosage and molecular weight requirements of the selective charge transport polymer are reduced, and at the same time, the coating performance of the raw materials is increased, thereby reducing the difficulty of preparing the selective charge transport layer.

[0054] In some embodiments, the polymer has a higher molecular weight than the selective charge transport polymer, allowing for better substrate coating. In other embodiments, because the polymer and the selective charge transport polymer form a copolymer, they can also better coat the substrate during a wet process, thereby reducing the probability of short circuits in the battery.

[0055] The present disclosure does not limit the specific materials of the high molecular weight polymer and the transport polymer. Those skilled in the art can select specific high molecular weight polymer and selective charge transport polymer materials according to actual conditions.

[0056] The selective charge transport layer provided herein can be the electron transport layer 13 or the hole transport layer 12 in a solar cell. The selective charge transport layer comprises a polymer as a matrix material and a selective charge transport polymer doped in the matrix material; or the selective charge transport layer comprises a copolymer formed by copolymerizing a selective charge transport polymer with a polymer; or the selective charge transport layer comprises a selective charge transport polymer, a polymer, and a copolymer. The selective charge transport polymer and the corresponding portion of the copolymer transport electrons or holes.

[0057] Taking perovskite cells as an example, when the selective charge transport polymer transports holes, the selective charge transport layer can serve as the hole transport layer 12 of the perovskite cell 10; when the selective charge transport polymer transports electrons, the selective charge transport layer serves as the electron transport layer 13 of the perovskite cell 10.

[0058] The molecular weight of the polymer is greater than 10,000. When used as the matrix material, the amount of the selective charge transport polymer can be reduced, significantly reducing costs. The current price of the selective charge transport polymer is around 18,000 yuan per gram, making the cost of the polymer essentially negligible compared to the selective charge transport polymer.

[0059] In some embodiments, the high molecular polymer is a continuous phase in the selective charge transport layer, and the selective charge transport polymer is doped therein. The selective charge transport polymer can transport electrons or holes.

[0060] In other embodiments, the selective charge transport layer is a copolymer film layer formed by a high molecular polymer and a selective charge transport polymer, and the partial structure of the copolymer corresponding to the selective charge transport polymer still has the function of transporting electrons or holes.

[0061] In other embodiments, the high molecular weight polymer serves as the continuous phase, interspersed with some selective charge transport polymers and the above-mentioned copolymers.

[0062] Optionally, the mass ratio of the polymer to the selective charge transport polymer is between 1:4 and 9:1, such as 1:4, 1:3, 1:2, 1:1, 2:1, 3:1, 4:1, 5:1, 6:1, 7:1, 8:1, 9:1, etc., or any value among the above adjacent values. Controlling the mass ratio of the polymer to the selective charge transport polymer within the above range can reduce the amount of the selective charge transport polymer as much as possible while ensuring the transport effect. Further preferably, when the mass ratio of the polymer to the selective charge transport polymer is between 2:3 and 3:2, the corresponding perovskite battery has better performance parameters.

[0063] Preferably, the mass ratio of the high molecular weight polymer to the selective charge transport polymer is between 2:3 and 3:2, for example, 2:3, 1:1, 3:2, etc., and more preferably, 1:1.

[0064] In the above-mentioned mass ratios of the high molecular weight polymer to the selective charge transport polymer, the mass ratios are understood to refer to the mass ratios of the respective raw materials in the precursor solution used to prepare the selective charge transport layer. If a copolymer is present in the selective charge transport layer, the mass ratios of the high molecular weight polymer to the selective charge transport polymer are inclusive of the corresponding mass of the copolymer.

[0065] If only the copolymer exists in the selective charge transport layer, and the mass ratio of the high molecular weight polymer to the selective charge transport polymer is between 1:4-9:1, it means that the mass ratio of the high molecular weight polymer used to prepare the copolymer to the selective charge transport polymer is between 1:4-9:1.

[0066] In some embodiments, the selective charge transport polymer is a polymer hole transport material used in the hole transport layer 12. In other embodiments, the selective charge transport polymer is a polymer electron transport material used in the electron transport layer 13.

[0067] Illustratively, the selective charge transport layer is a hole transport layer, and the polymer hole transport material used to prepare the hole transport layer can be a combination of one or more of PTAA, Poly-TPD, P3HT, PEDOT, EDOT:PSS, PANI, or one or more derivatives thereof.

[0068] Illustratively, the selective charge transport layer is an electron transport layer, and the polymer electron transport material for preparing the electron transport layer may include a combination of one or more of N2200, N2300, N-CS2DPP-OD-TEG, P-BNBP-T, P-IFDMT4 / , or one or more derivatives thereof.

[0069] The derivatives can be, for example, N2200, X=S and PNDIBS, X=Se, or PNDIF-T2, PNBSF, PNDIV-BT, P4, 30PDI, NOE10 (X=0.1) and PNDI0.5 (X=0.5), P(NDI20D-TZ2), TEG-N2200, PNDIT-F3N, PDI-V, PDTZTI, PBIT1, f-BIT2-FT, f-BIT2-T or PTZBITT.

[0070] The materials and ratios of the polymer hole transport material are not specifically limited in the embodiments of the present disclosure, and those skilled in the art can select one, two, or three of the above materials. Similarly, the materials and ratios of the polymer electron transport material are not specifically limited in the embodiments of the present disclosure, and those skilled in the art can select one, two, or three of the above materials.

[0071] In one possible implementation of the present invention, the high molecular polymer in the selective charge transport layer is a combination of one or more of cross-linked polydimethylsiloxane (PDMS), polymethyl methacrylate (PMMA), polyvinyl pyrrolidone (PVP), poly-4-ethylphenol (POLY), polyethylene terephthalate (PET), polystyrene (PS), polyvinyl chloride (PVC), polypropylene (PP), polyethylene (PE), polylactic acid (PLA), polyoxymethylene (POM), polyamide (PA), polyimide (PI), polyethyleneimine, polydopamine, polyvinylidene fluoride (PVDF), and polyacrylonitrile (PAN), or a copolymer of one or more of the following.

[0072] Specifically, the materials and ratios of the high molecular polymers are not specifically limited in the embodiments of the present disclosure, and those skilled in the art can select one, two or three of the above materials.

[0073] In another embodiment of the present disclosure, a selective charge transport layer is provided, which is made of one (or more) of the above-listed high molecular weight polymers and one (or more) of the above-listed selective charge transport polymers. Furthermore, the raw materials for preparing the selective charge transport layer may or may not contain a copolymer of the two.

[0074] In another achievable embodiment of the present disclosure, a selective charge transport layer is provided, which is made of a copolymer, wherein the copolymer is formed by copolymerization of one (or more) of the high molecular weight polymers listed above and one (or more) of the selective charge transport polymers listed above.

[0075] Specifically, the materials and ratios of the polymer hole transport material are not limited in the embodiments of the present disclosure, and those skilled in the art can select one, two or three of the above materials. Similarly, the materials and ratios of the polymer electron transport material are not limited in the embodiments of the present disclosure, and those skilled in the art can select one, two or three of the above materials. In addition, the molecular weight of the selective charge transport polymer or high molecular weight polymer is not specifically limited. As long as the overall performance of the transport layer meets the conductivity, the molecular weight or degree of polymerization can be selected according to the film formation needs.

[0076] In addition, illustratively, a hole transport layer is provided, which is made of Poly-TPD, P3HT and PMMA. Since Poly-TPD and P3HT are highly hydrophobic, when the hole transport layer 12 only uses Poly-TPD and P3HT, when the perovskite film layer 11 is set on the hole transport layer 12, the perovskite film layer 11 is not easy to deposit on its surface. Even if it is deposited, due to the low interfacial bonding force, the efficiency of the perovskite battery 10 will be low and the stability will be poor. The hole transport layer 12 of the embodiment of the present disclosure uses polymer hole transport materials and high molecular polymers. Some of the high molecular polymers (such as PMMA) are more friendly to the wettability of the solution of the perovskite film layer 11, which can improve the bonding force between the hole transport layer 12 and the perovskite film layer 11, avoiding the problem of low efficiency and poor stability of the perovskite battery 10 caused by low interfacial bonding force.

[0077] In one possible implementation of the present disclosure, the high molecular polymer may also contain a coordination group for passivating defects in the perovskite film layer 11; optionally, the coordination group includes one or more of an amino group, a carboxyl group, a hydroxyl group, a benzene ring, and a sulfonic acid group, or may be other coordination groups with a passivation effect that are not listed.

[0078] When the hole transport layer 12 uses only one or more of PTAA, Poly-TPD, P3HT, PEDOT, EDOT:PSS, and PANI, it contacts the perovskite film layer 11 to collect holes. However, the above materials will cause interfacial recombination with the perovskite film layer 11 at the interface between the perovskite film layer 11 and the hole transport layer 12, thereby reducing the efficiency of the perovskite battery 10. The hole transport layer 12 of the embodiment of the present disclosure includes a polymer hole transport material and a high molecular polymer. The high molecular polymer contains a ligand for passivating the defects of the perovskite film layer 11. The ligand has a large proportion at the interface, which can effectively reduce the interfacial recombination, thereby improving the efficiency of the perovskite battery 10. In addition, due to its extremely high molecular weight, the high molecular polymer can completely cover the rough deposition surface, which is beneficial for the perovskite battery 10 to deal with short-circuit channels. Alternatively, the hole transport layer 12 of the embodiment of the present disclosure includes a copolymer formed by a polymer hole transport material and a high molecular polymer, and the copolymer contains a ligand for passivating the defects of the perovskite film layer 11.

[0079] Optionally, the ligands include one or more of amino, carboxyl, hydroxyl, benzene ring, sulfonic acid, or others. Carboxyl, benzene ring, and other ligands can effectively reduce interfacial recombination, thereby improving the efficiency of the perovskite cell 10.

[0080] Specifically, the carboxyl groups in PTAA, the benzene rings in PEDOT, and the high electronegativity of the F group in P3HT can all reduce interfacial recombination. It should be noted that the aforementioned ligands are merely examples and are not intended to limit the scope of ligands. Those skilled in the art may select other ligands based on practical needs.

[0081] In one possible implementation of the embodiment of the present disclosure, the selective charge transport layer may be doped with an additive for improving carrier mobility, and the additive may include one or both of Li-TFSI and Tbp.

[0082] The selective charge transport layer is also doped with additives, which are used to improve carrier mobility, thereby further reducing the amount of the selective charge transport polymer.

[0083] Another aspect of the embodiments of the present disclosure provides a precursor liquid for preparing a selective charge transport layer, comprising a high molecular weight polymer, a selective charge transport polymer and a solvent; the selective charge transport polymer utilizes electrons or holes to transport charges; and the molecular weight of the high molecular weight polymer is greater than 10,000.

[0084] As an implementation of the embodiment of the present disclosure, the precursor liquid may also include a copolymer of a high molecular polymer and a selective charge transport polymer.

[0085] The present disclosure also provides another precursor solution for preparing a selective charge transport layer, the precursor solution comprising a polymer, a copolymer of the polymer and the selective charge transport polymer, and a solvent. The copolymer can transport charges using electrons or holes.

[0086] The precursor liquid is used to prepare the selective charge transport layer. The material of the selective charge transport layer has been described in detail in the selective charge transport layer and will not be repeated here. The specific material of the solvent is not limited in the present embodiment, and chlorobenzene can be used as an example.

[0087] As an practicable approach, the mass ratio of the polymer to the selective charge transport polymer is between 1:4-9:1; preferably, the mass ratio of the polymer to the selective charge transport polymer is between 2:3-3:2. Current experiments have shown that, under the same other experimental conditions, the performance of the device corresponding to this ratio range is better.

[0088] As an practicable manner, the high molecular polymer is one or more combinations of cross-linked polydimethylsiloxane, polymethyl methacrylate, polyvinyl pyrrolidone, poly-4-ethylphenol, polybutylene terephthalate, polystyrene, polyvinyl chloride, polypropylene, polyethylene, polylactic acid, polyformaldehyde, polyamide, polyimide, polyethyleneimine, polydopamine, polyvinylidene fluoride, polyacrylonitrile, or one or more copolymers.

[0089] As an practicable approach, the precursor liquid may include Poly-TPD, PMMA, and PTAA, and the mass concentration ratio of the three is 3:4:3.

[0090] It should be added that, for the introduction of the selective charge transport polymer, please refer to the introduction of the selective charge transport layer in this disclosure, and no repetition is made here.

[0091] In another aspect of the embodiments of the present disclosure, as shown in FIG. 1 and FIG. 2 , a perovskite cell 10 is provided, comprising a perovskite film layer and the aforementioned selective charge transport layer.

[0092] The perovskite cell 10 in FIG1 includes the selective charge transport layer. The specific structure and beneficial effects of the selective charge transport layer have been described in detail in the above embodiments and will not be repeated here.

[0093] Another aspect of the present disclosure provides a method for preparing a perovskite battery, which uses the following process for preparing a selective charge transport layer, including:

[0094] The precursor liquid of the selective charge transport layer is coated on a substrate to form a selective charge transport layer. The selective charge transport layer includes a high molecular weight polymer as a matrix material, a selective charge transport polymer doped in the matrix material, and / or a copolymer formed by the high molecular weight polymer and the selective charge transport polymer.

[0095] When the selective charge transport layer includes a copolymer, it may also include a high molecular polymer that is not copolymerized and a selective charge transport polymer.

[0096] Specifically, the perovskite cell 10 can be disposed on a crystalline silicon bottom electrode or a transparent conductive film. The following describes in detail two methods for preparing the perovskite cell 10 .

[0097] A method for preparing a perovskite battery 10, as shown in FIG2 and FIG3, includes:

[0098] S10: As shown in FIG3 , a crystalline silicon bottom cell 14 is provided, and a hole transport layer 12 is prepared on the crystalline silicon bottom cell 14 . The hole transport layer 12 uses a precursor liquid containing a high molecular weight polymer and a polymer hole transport material provided by the present disclosure;

[0099] The crystalline silicon bottom cell 14 is made of silicon material, and the crystalline silicon bottom cell 14 is provided, cleaned and dried to keep its surface clean and dry. Specific cleaning steps can be set by those skilled in the art according to actual conditions.

[0100] When preparing the hole transport layer 12 on the crystalline silicon base cell 14, a wet process is used. Specifically, a polymer and a polymer hole transport material are dissolved in an organic solvent at a specific mass ratio to form a precursor solution. This is then spin-coated onto the crystalline silicon base cell 14 and dried to evaporate the organic solvent. Specifically, the polymer is PMMA and the polymer hole transport material is PTAA, with a mass ratio of 1:1. The precursors are dissolved in 2 mg / ml of chlorobenzene. The molecular weight of PMMA is 350,000, and that of PTAA is 7,000.

[0101] S11: As shown in FIG3 , forming a perovskite film layer 11 on the hole transport layer 12;

[0102] The preparation of the perovskite film layer 11 specifically includes two steps:

[0103] S111: Forming a metal halide skeleton on the hole transport layer 12. Dissolve lead iodide and cesium iodide in 1 ml of a mixed solution of dimethylformamide and dimethyl sulfoxide (DMSO) at a volume ratio of 9:1. Stir in a 70°C water bath to fully dissolve the mixture to form a spin coating solution. Spin coat the spin coating solution onto the hole transport layer 12. Specifically, spin coat at 2500 rpm for 30 seconds, then anneal on a hot plate at 70°C for 1 minute to complete the preparation of the metal halide skeleton.

[0104] S112: forming a perovskite film layer 11.

[0105] Methionine hydrobromide and methionine hydroiodide were dissolved in isopropanol at a molar ratio of 1.75:1 to form a coating solution, and the coating solution was spin-coated on the metal halide skeleton. Specifically, the coating solution was spin-coated at a speed of 3000 rpm for 30 seconds, and then annealed on a hot plate at 150°C for 30 minutes to complete the preparation of the perovskite film layer 11.

[0106] S12: As shown in FIG3 , an electron transport layer 13 is formed on the perovskite film layer 11 ;

[0107] The specific method and materials for forming the electron transport layer 13 on the perovskite film layer 11 are not limited in the present embodiment, and those skilled in the art can select them according to actual conditions. For example, the electron transport layer 13 can be formed on the perovskite film layer 11 by vacuum coating. Specifically, the crystalline silicon bottom cell 14 with the perovskite film layer 11 is placed in a vacuum coating device, and a 20 nm thick C layer is evaporated on the perovskite film layer 11. 60 , the evaporation rate is Can be re-instated in C 60 A 7nm thick BCP is evaporated on top. BCP serves as a buffer layer. On the one hand, BCP has a deeper HOMO energy level, which can effectively block holes and help improve the photoelectric conversion efficiency of the device. On the other hand, BCP can be regarded as an electron-rich group because its molecules contain N atoms with lone pairs of electrons, which passivate the halogen vacancy defects on the surface of the perovskite film layer 11, thereby reducing interfacial recombination and improving electron transmission at the interface. The hydrophobic benzene ring in the BCP molecule is also conducive to enhancing the resistance of the interface to the external environment and improving the stability of the device.

[0108] S13: As shown in FIG3 , an electrode 16 is prepared on the electron transport layer 13 to form a crystalline silicon perovskite stacked cell.

[0109] Specifically, a copper electrode 16 with a thickness of 150 nm may be deposited on the buffer layer BCP using a mask method.

[0110] The disclosed embodiments can be used in crystalline silicon perovskite tandem cells, and can also be used in other tandem cells containing perovskite film layers, to improve the quality of the film layer, reduce the amount of selective charge transfer polymer used, and have a certain effect of improving the photoelectric conversion efficiency.

[0111] Another aspect of the embodiments of the present disclosure provides a method for preparing a single-junction perovskite cell 10, as shown in FIG4 , comprising:

[0112] S20: As shown in FIG5 , a glass substrate having a transparent conductive layer 17 is provided, and an electron transport layer 13 is prepared on the transparent conductive layer 17 ; the electron transport layer 13 uses a polymer electron transport material and a high molecular polymer material.

[0113] The transparent conductive glass has a transparent conductive layer 17. After providing the transparent conductive glass, the transparent conductive glass is cleaned and dried to keep its surface clean and dry. Those skilled in the art can set the specific cleaning steps according to actual conditions. For example, the glass can be cleaned in sequence using glass detergent, deionized water, acetone, and anhydrous ethanol, and then blown dry with dry gas.

[0114] The electron transport layer 13 is spin-coated using a mixed solution of N2200 and PMMT.

[0115] S21: As shown in FIG5 , a perovskite film layer 11 is formed on the electron transport layer 13 ; the preparation method of the perovskite film layer 11 is the same as that in the above embodiment, and will not be described in detail here.

[0116] S22: As shown in FIG5 , a hole transport layer 12 is prepared on the perovskite film layer 11 . The hole transport layer 12 uses a polymer hole transport material and a high molecular polymer.

[0117] When preparing the hole transport layer 12 on the perovskite film layer 11, a wet process is used. Specifically, a polymer and a polymer hole transport material are dissolved in an organic solvent at a certain mass ratio to form a precursor liquid. The precursor liquid is then spin-coated onto the perovskite film layer 11 and dried to evaporate the organic solvent. Specifically, the polymer can be PS and the polymer hole transport material can be Poly-TPD, with a mass ratio of 1:1, and the two are dissolved in 2 mg / ml chlorobenzene. The molecular weight of PS is 280,000, and the molecular weight of Poly-TPD is 30,000.

[0118] S23 : As shown in FIG. 5 , an electrode 16 is prepared on the hole transport layer 12 to form a perovskite cell 10 .

[0119] Specifically, a gold electrode 16 with a thickness of 150 nm is deposited on the hole transport layer 12 using a mask method.

[0120] In order to further verify the effect of the selective charge transport layer provided in the embodiment of the present disclosure on the performance of the perovskite cell 10, the present disclosure performs performance tests on different hole transport layers 12 (with different polymer contents). Specifically, 5 groups of perovskite cells 10 with different hole transport layers 12 were prepared using the same process and the same environment. Each perovskite cell 10 had 5 samples, and the short-circuit current (Jsc), photoelectric conversion efficiency (PCE), open circuit voltage (Voc), and fill factor (FF) of each perovskite cell 10 were tested. Among them, the specific material ratio of the hole transport layer 12 and the test data are shown in Table 1:

[0121] Table 1 Performance comparison of multiple groups of perovskite cells 10

[0122] It should be noted that the numerical values ​​of each detection value in Table 1 are the average values ​​of five perovskite batteries 10 under the same conditions. In order to more clearly show the conditions of each sample in each group, the data of multiple perovskite batteries 10 are made into box plots with each group as the unit. As shown in Figure 6, a box plot of the short-circuit current of multiple perovskite batteries 10 is made with each group as the unit; as shown in Figure 7, a box plot of the photoelectric conversion efficiency of multiple perovskite batteries 10 is made with each group as the unit; as shown in Figure 8, a box plot of the open-circuit voltage of multiple perovskite batteries 10 is made with each group as the unit; and as shown in Figure 9, a box plot of the fill factor of multiple perovskite batteries 10 is made with each group as the unit.

[0123] As can be seen from Table 1 and Figures 6 to 9, when the hole transport layer 12 is added with a polymer, its performance is not significantly affected. As a reference, the short-circuit current (Jsc) of the perovskite cell without the addition of the polymer is 19.9 mA·cm 2 The photoelectric conversion efficiency (PCE) was 30.3%, the open circuit voltage (Voc) was 1.88 V, and the fill factor (FF) was 80.8%. After adding polymers in different proportions, the short-circuit current (Jsc) of each group of perovskite cells was 19.7-20 mA·cm 2 , photoelectric conversion efficiency (PCE) 29.3% ~ 31.5%, open circuit voltage (Voc) 1.85 ~ 1.87V, fill factor (FF) 79.4% ~ 83.6%.

[0124] The addition of a high molecular weight polymer to the inner hole transport layer reduces the amount of polymer hole transport material required, thereby simplifying the preparation of the hole transport layer 12 of the perovskite cell 10. This significantly reduces the amount of expensive polymer hole transport material required, while maintaining minimal impact on device performance. The same principle applies to the electron transport layer 13, which will not be discussed further here.

[0125] In addition, based on the comprehensive consideration of various parameters, the third group of perovskite cells 10 have good performance in all directions, with a photoelectric conversion efficiency of 31.5%, an open circuit voltage of 1.87V, a fill factor of 83.6%, and a short-circuit current density of 20mA·cm 2 The fill factor reflects the conductivity of the hole transport layer 12. The fill factor of the third group is higher than that of the first group in the comparative test. Therefore, the conductivity of the hole transport layer 12 of the third group of perovskite cells 10 is higher than that of the hole transport layer 12 without the polymer.

[0126] In addition, in order to further verify the beneficial effects of the embodiments of the present disclosure, wettability tests were performed on the comparative example (sample A) and the embodiment (sample B), and the results are as follows:

[0127] The perovskite wettability of the hole transport layer surface of sample A (containing only polymer hole transport material Poly-TPD) and sample B (containing polymer hole transport material Poly-TPD and high molecular weight polymer PTAA) as reference was tested, and the results are shown in Figures 10 and 11.

[0128] In Figure 10, the solution is the perovskite precursor solution, and the contact surface is the hole transport layer formed by Poly-TPD. Wettability contact angle measurements were performed, and the measured contact angles were 49.785° and 49.509°.

[0129] In Figure 11, the solution is the perovskite precursor solution (the same as in Figure 10), and the contact surface is the hole transport layer formed by Poly-TPD and PMMA. Wettability contact angle measurements were performed, and the measured contact angles were 11.415° and 11.877°.

[0130] It can be seen that PMMA is added to the hole transport layer of sample B. Due to the presence of carboxyl ligands on the PMMA surface, the wettability of the perovskite solution is significantly improved, which helps to increase the yield of perovskite film formation, enhance the mechanical strength of the interface, and improve long-term stability.

[0131] Those skilled in the art will appreciate that Figures 1, 3, and 5 illustrate only the basic membrane layers that make up a perovskite cell. These are for illustrative purposes only and are not intended to limit the cell structure. Single-junction cells may further include other membrane layers, such as a passivation layer or a finishing layer. Tandem cells, in addition to the aforementioned membrane layers, may also include a composite layer between the crystalline silicon sub-cell and the perovskite sub-cell.

[0132] The foregoing description is merely a preferred embodiment of the present disclosure and is not intended to limit the present disclosure. Those skilled in the art will readily appreciate that various modifications and variations are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present disclosure shall be included within the scope of protection of the present disclosure. Industrial Applicability

[0133] The present disclosure improves the composition of the selective charge transport layer by adding a high molecular weight polymer having a molecular weight greater than 10,000. When the high molecular weight polymer is set as the matrix material, the amount of the selective charge transport polymer used can be reduced, while the coating properties of the material are increased to facilitate film formation. Therefore, the present disclosure reduces the material amount of the selective polymer without affecting (or substantially affecting) the function of the selective charge transport layer, can significantly reduce the cost of the selective charge transport layer, and has very good market application prospects.

Claims

1. A selective charge transport layer, wherein the selective charge transport layer is used for a solar cell, characterized in that: Including a high molecular polymer as a matrix material; a selective charge transport polymer doped in the matrix material, and / or a copolymer formed by the high molecular polymer and the selective charge transport polymer; wherein, The selective charge transport polymer transports electrons or holes; the molecular weight of the high molecular polymer is greater than 10,000.

2. The selective charge transport layer according to claim 1, wherein The mass ratio of the high molecular weight polymer to the selective charge transport polymer is between 1:4 and 9:

1.

3. The selective charge transport layer according to claim 1 or 2, characterized in that The mass ratio of the high molecular weight polymer to the selective charge transport polymer is between 2:3 and 3:

2.

4. The selective charge transport layer according to any one of claims 1 to 3, characterized in that The high molecular polymer is one or more of cross-linked polydimethylsiloxane, polymethyl methacrylate, polyvinyl pyrrolidone, poly-4-ethylphenol, polyethylene terephthalate, polystyrene, polyvinyl chloride, polypropylene, polyethylene, polylactic acid, polyformaldehyde, polyamide, polyimide, polyethyleneimine, polydopamine, polyvinylidene fluoride and polyacrylonitrile, or a copolymer of one or more of the above.

5. The selective charge transport layer according to any one of claims 1 to 4, characterized in that The selective charge transport polymer is a polymer hole transport material for a hole transport layer, or a polymer electron transport material for an electron transport layer.

6. The selective charge transport layer according to claim 5, characterized in that The polymer hole transport material is a combination of one or more of PTAA, Poly-TPD, P3HT, PEDOT, PEDOT:PSS, PANI, or a derivative of one or more thereof; The polymer electron transport material includes a combination of one or more of N2200, N2300, N-CS2DPP-OD-TEG, P-BNBP-T, and P-IFDMT4, or a derivative of one or more of the above.

7. The selective charge transport layer according to any one of claims 1 to 6, characterized in that The high molecular polymer contains a coordination group for passivating defects in the perovskite film; the coordination group includes one or more of an amino group, a carboxyl group, a hydroxyl group, a benzene ring, and a sulfonic acid.

8. The selective charge transport layer according to any one of claims 1 to 6, characterized in that The nanostructured carbon fiber is further doped with an additive for improving carrier mobility, wherein the additive is selected from at least one of Li-TFSI and tBP.

9. A precursor liquid for preparing a selective charge transport layer, characterized in that: include: A high molecular weight polymer, a selective charge transport polymer, and / or a copolymer formed by the high molecular weight polymer and the selective charge transport polymer, and a solvent, wherein: The selective charge transport polymer utilizes electrons or holes to transport charges; the molecular weight of the high molecular polymer is greater than 10,000.

10. The precursor liquid according to claim 9, characterized in that The mass ratio of the high molecular weight polymer to the selective charge transport polymer is between 1:4 and 9:

1.

11. The precursor liquid according to claim 9 or 10, characterized in that The mass ratio of the high molecular weight polymer to the selective charge transport polymer is between 2:3 and 3:

2.

12. The precursor liquid according to any one of claims 9 to 11, characterized in that The high molecular polymer is a combination of one or more of cross-linked polydimethylsiloxane, polymethyl methacrylate, polyvinyl pyrrolidone, poly-4-ethylphenol, polyethylene terephthalate, polystyrene, polyvinyl chloride, polypropylene, polyethylene, polyvinyl alcohol, polylactic acid, polycarbonate, polyacrylic acid, plastic starch material, polysulfone, polyurethane, polyformaldehyde, polyamide, polyimide, polyamideimide, polyethyleneimine, polydopamine, polyvinylidene fluoride, polyacrylonitrile, polyetheretherketone, epoxy resin and ABS resin, or a copolymer of one or more of them.

13. The precursor liquid according to any one of claims 9 to 12, characterized in that The precursor liquid includes Poly-TPD, PMMA and PTAA, and the mass concentration ratio of the three is 3:4:

3.

14. A perovskite battery, characterized in that: The method comprises a perovskite film layer and a selective charge transport layer according to any one of claims 1 to 8.

15. A method for preparing a perovskite battery, comprising a process for preparing a selective charge transport layer, characterized in that: The preparation process of the selective charge transport layer comprises: The precursor liquid according to any one of claims 9 to 13 is coated on a substrate to form a selective charge transport layer, wherein the selective charge transport layer includes a high molecular weight polymer as a matrix material, a selective charge transport polymer doped in the matrix material; and / or a copolymer formed by the high molecular weight polymer and the selective charge transport polymer.

16. An electrical device, characterized in that: A perovskite battery comprising the perovskite battery according to claim 14 or a perovskite battery prepared by the preparation method of the perovskite battery according to claim 15.

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