Composite perovskite thin film and preparation method and application thereof

Abstract

The invention provides a composite perovskite thin film and a preparation method and application thereof, and the preparation method comprises the following steps: (1) coating a nickel oxide substrate with an SAM precursor solution, and carrying out the first drying treatment to form an SAM modified layer; (2) coating the SAM modified layer with a perovskite precursor solution, and carrying out second drying treatment to obtain a precursor film; and (3) carrying out annealing treatment on the precursor thin film to obtain the composite perovskite thin film, wherein the solute of the SAM precursor solution comprises an SAM material and a silane coupling agent, and the solvent of the SAM precursor solution is the same as that of the perovskite precursor solution. According to the method disclosed by the invention, the dispersion uniformity of the SAM material on the nickel oxide layer can be improved, the adhesive force of the SAM material is improved, the wettability of perovskite on the SAM single film is greatly improved through a proper preparation process, the generation of perovskite defects is reduced, and the film quality of the perovskite is further improved.

Description

Technical Field

[0001] The invention belongs to the technical field of solar cells and relates to a composite perovskite film and a preparation method and application thereof. Background Art

[0002] After 50 years of development, solar photovoltaic modules are divided into the first generation of crystalline silicon solar cells, the second generation of semiconductor compound thin film cells and the third generation of perovskite solar cells. The technological iteration of solar cells is one of the important ways to reduce the cost of electricity, but with the continuous deepening of the industrialization process of perovskites, improving efficiency and reducing costs will become the main direction of the sustainable development of perovskites. The photoelectric conversion efficiency of perovskite solar cells is the main means to compete with traditional crystalline silicon for the market, so the continuous optimization of the electrical performance of modules will become the main direction in the future.

[0003] At present, the efficiency of small-area perovskite cells has exceeded 26%, but the efficiency of large-area or even square-meter perovskite modules is still far from 26%. In the process of industrialization, the defects between large-area perovskites and interfaces increase geometrically compared to those between small sizes, which is also the main reason for the decline in efficiency. Self-assembled molecules (SAM) have become the mainstream choice for hole transport layers in high-efficiency single-junction and tandem stacked solar cells due to their advantages such as high hole selectivity, fast hole transfer rate, and low interface trap state density. However, due to the weak bonding force, poor wettability, uneven coverage, and poor thermal stability between SAM and FTO substrate, the application of high-efficiency and stable large-area perovskite modules is restricted.

[0004] CN118921997A discloses a perovskite solar cell with a self-organized monolayer hole transport material, comprising from top to bottom a transparent conductive substrate, an electron transport layer, a perovskite light absorption layer, a hole transport layer and a metal electrode, wherein the hole transport layer is made of a self-organized monolayer hole transport material.

[0005] CN118922003A discloses a solar cell and a preparation method thereof, and a photovoltaic module, wherein the solar cell comprises a substrate and a hole transport layer, a hole modification layer and a perovskite layer sequentially arranged on the substrate, wherein the hole modification layer is located between the hole transport layer and the perovskite layer; and the hole modification layer comprises a self-assembled monomolecular material.

[0006] The perovskite layer described in the above scheme is prepared on a nickel oxide substrate with SAM prepared on it. However, due to the poor wettability of SAM, there will be obvious areas without perovskite during the preparation of large-size perovskite films. Therefore, increasing the interface wettability between SAM and perovskite / NIO will become the key to improving large-area perovskite components. Summary of the invention

[0007] The purpose of the present invention is to provide a composite perovskite film and a preparation method and application thereof. The method of the present invention can improve the uniformity of dispersion of SAM materials on the nickel oxide layer and enhance the adhesion of the SAM material. Through a suitable preparation process, the wettability of perovskite on the SAM single film is greatly improved, the generation of perovskite defects is reduced, and the quality of the perovskite film is further improved.

[0008] In order to achieve the purpose of the invention, the present invention adopts the following technical solutions:

[0009] In a first aspect, the present invention provides a method for preparing a composite perovskite film, the preparation method comprising the following steps:

[0010] (1) coating a SAM precursor solution on a nickel oxide substrate and forming a SAM modified layer through a first drying process;

[0011] (2) coating a perovskite precursor solution on the SAM modified layer, and obtaining a precursor film through a second drying process;

[0012] (3) annealing the precursor film to obtain the composite perovskite film;

[0013] The solute of the SAM precursor solution includes a SAM material and a silane coupling agent, and the solvent of the SAM precursor solution and the perovskite precursor solution are the same.

[0014] In the preparation process of the composite perovskite film of the present invention, after the SAM precursor solution is applied, the phosphonic acid group of the SAM material itself will form a hydrogen bond or a covalent bond with the reactive group in the silane coupling agent, and the hydrolysis group in the silane coupling agent will preferentially react with the water molecules attached to the surface of the nickel oxide (after the nickel oxide is prepared, it will stay in the production line, resulting in the adsorption of water in the air on the surface), and in the subsequent annealing process, it will react with the hydroxyl groups on the surface of the nickel oxide to form a strong Si-O-Si chemical bond to achieve uniform anchoring of the SAM and the nickel oxide, thereby reducing the defects of the traditional SAM itself in the isopropanol system, that is, unevenness and poor adhesion. The SAM precursor solution and perovskite use the same solvent, and the residual solvent in the SAM semi-dry film is achieved by controlling the parameters of the drying process. The perovskite precursor is directly coated without annealing. Since the residual solvent in the SAM semi-dry film is controlled by controlling the drying process, and the perovskite precursor uses the same solvent system, the wettability of the perovskite on the SAM single film is greatly improved under the principle of like dissolves like, the generation of perovskite defects is reduced, and the quality of the perovskite film is further improved.

[0015] Preferably, the solvent of the SAM precursor solution in step (1) comprises a volatile solvent and / or a non-volatile solvent.

[0016] The saturated vapor pressure of the non-volatile solvent of the present invention is >1000Pa, and the saturated vapor pressure of the volatile solvent is <100Pa.

[0017] Preferably, the volatile solvent is any one of N,N-dimethylformamide (DMF), 2-methoxyethanol, ethanol, tetrahydrofuran (THF), N,N-dimethylacetamide (DMA), acetonitrile or γ-butyrolactone (γ-GBL) or a combination of at least two thereof. Typical but non-limiting combinations include a combination of DMF and DMA, a combination of THF and DMF, or a combination of γ-GBL and DMF.

[0018] Preferably, the non-volatile solvent includes any one of dimethyl sulfoxide (DMSO), N-methylpyrrolidone (NMP) or dimethyl-2-imidazolidinone (DMI) or a combination of at least two thereof. Typical but non-limiting combinations include a combination of DMSO and DMI, a combination of NMP and DMI, or a combination of DMSO and NMP.

[0019] Preferably, the SAM material includes any one of 2-(9H-carbazole-9-yl)ethylphosphonic acid (2PACz), 4-(3,6-dimethyl-9H-carbazole-9-yl)butyl)phosphonic acid (Me-4PACz), 4-(7H-dibenzocarbazole-7-yl)butylphosphonic acid (A-4PADCB) or 2-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl)phosphonic acid (MeO-2PACz), or a combination of at least two thereof. Typical but non-limiting combinations include a combination of 2PACz and Me-4PACz, a combination of Me-4PACz and MeO-2PACz, or a combination of MeO-2PACz and A-4PADCB, etc.

[0020] Preferably, the silane coupling agent includes any one of γ-aminopropyltriethoxysilane (KH550), 3-(2,3-epoxypropoxy)propyltrimethoxysilane (KH560), 3-(trimethoxysilyl)propyl methacrylate (KH570), γ-mercaptopropyltrimethoxysilane (KH590) or vinyltrimethoxysilane (A-171) or a combination of at least two thereof. Typical but non-limiting combinations include a combination of KH550 and KH590, a combination of KH590 and KH570, or a combination of KH560 and A-171.

[0021] Preferably, in the SAM precursor solution of step (1), the mass concentration of the SAM material is 0.1 g / L to 10 g / L, for example, 0.1 g / L, 0.5 g / L, 1 g / L, 5 g / L or 10 g / L, etc., not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0022] Preferably, in the SAM precursor solution of step (1), the volume concentration of the silane coupling agent is 0.1 mL / L to 10 mL / L, for example, 0.1 mL / L, 0.5 mL / L, 1 mL / L, 5 mL / L or 10 mL / L, etc., not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0023] Preferably, the coating method in step (1) includes slit coating.

[0024] Preferably, the slit coating speed is 10 mm / s to 60 mm / s, for example, 10 mm / s, 20 mm / s, 30 mm / s, 40 mm / s, 50 mm / s or 60 mm / s, etc., not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0025] Preferably, the injection speed of the slit coating is 80 μL / s to 300 μL / s, for example, 80 μL / s, 100 μL / s, 150 μL / s, 200 μL / s or 300 μL / s, etc., not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0026] Preferably, during the slit coating process, the distance between the coating head and the substrate is 50 μm to 200 μm, for example, 50 μm, 80 μm, 100 μm, 150 μm or 200 μm, etc., not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0027] Preferably, the first drying treatment in step (1) comprises vacuum drying.

[0028] Preferably, the chamber pressure of the first drying treatment in step (1) is 0.1Pa to 100Pa, for example, 0.1Pa, 5Pa, 10Pa, 50Pa or 100Pa, etc., and is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0029] Preferably, the vacuuming time of the first drying treatment in step (1) is 10s to 100s, for example 10s, 20s, 50s, 80s or 100s, etc., and is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0030] The first drying process of the present invention is performed only by vacuuming without adjusting the temperature.

[0031] Preferably, the chemical formula of the solute in the perovskite precursor solution in step (2) is Cs x (FA y MA 1-y )1-xPb(Iz Br 1-z )3, x is 0 to 1 but not 0, y is 0 to 1 but not 0, z is 0 to 1 but not 0.

[0032] Preferably, the solvent of the perovskite precursor solution in step (2) includes a volatile solvent and / or a non-volatile solvent.

[0033] Preferably, the volatile solvent is any one of N,N-dimethylformamide (DMF), 2-methoxyethanol, ethanol, tetrahydrofuran (THF), N,N-dimethylacetamide (DMA), acetonitrile or γ-butyrolactone (γ-GBL) or a combination of at least two thereof. Typical but non-limiting combinations include a combination of DMF and DMA, a combination of THF and DMF, or a combination of γ-GBL and DMF.

[0034] Preferably, the non-volatile solvent includes any one of dimethyl sulfoxide (DMSO), N-methylpyrrolidone (NMP) or dimethyl-2-imidazolidinone (DMI) or a combination of at least two thereof. Typical but non-limiting combinations include a combination of DMSO and DMI, a combination of NMP and DMI, or a combination of DMSO and NMP.

[0035] Preferably, the molar concentration of the perovskite precursor solution in step (2) is 0.2 mol / L to 1.5 mol / L, for example: 0.2 mol / L, 0.5 mol / L, 0.8 mol / L, 1 mol / L, 1.2 mol / L or 1.5 mol / L, etc., not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0036] Preferably, the coating method in step (2) includes slit coating.

[0037] Preferably, the slit coating speed is 10 mm / s to 60 mm / s, for example, 10 mm / s, 20 mm / s, 30 mm / s, 40 mm / s, 50 mm / s or 60 mm / s, etc., not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0038] Preferably, the injection speed of the slit coating is 80 μL / s to 300 μL / s, for example, 80 μL / s, 100 μL / s, 150 μL / s, 200 μL / s or 300 μL / s, etc., not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0039] Preferably, during the slit coating process, the distance between the coating head and the substrate is 50 μm to 200 μm, for example, 50 μm, 80 μm, 100 μm, 150 μm or 200 μm, etc., not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0040] Preferably, the second drying treatment in step (2) comprises vacuum drying.

[0041] Preferably, the chamber pressure of the second drying treatment in step (2) is 0.1Pa to 100Pa, for example, 0.1Pa, 5Pa, 10Pa, 50Pa or 100Pa, etc., and is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0042] Preferably, the vacuuming time of the second drying treatment in step (2) is 10s to 100s, for example, 10s, 20s, 50s, 80s or 100s, etc., and is not limited to the listed values. Other values ​​not listed within the numerical range are also applicable.

[0043] Preferably, the temperature of the annealing treatment in step (3) is 100°C to 200°C, for example, 100°C, 120°C, 150°C, 180°C or 200°C, etc., and is not limited to the listed values. Other values ​​not listed within the numerical range are also applicable.

[0044] Preferably, the annealing time in step (3) is 10 min to 60 min, for example, 10 min, 20 min, 30 min, 40 min, 50 min or 60 min, etc., not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0045] Preferably, the transmission speed of the annealing treatment in step (3) is 0.1m / min to 1m / min, for example: 0.1m / min, 0.2m / min, 0.5m / min, 0.8m / min or 1m / min, etc., not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0046] In a second aspect, the present invention provides a composite perovskite film, which is prepared by the preparation method described in the first aspect.

[0047] Preferably, the composite perovskite film comprises a nickel oxide base layer, a SAM modified layer and a perovskite active layer which are stacked in sequence.

[0048] Preferably, the nickel oxide base layer has a thickness of 5 nm to 100 nm, for example, 5 nm, 8 nm, 10 nm, 20 nm, 50 nm or 100 nm.

[0049] Preferably, the thickness of the SAM modified layer is 1 nm to 100 nm, for example, 1 nm, 5 nm, 10 nm, 20 nm, 50 nm or 100 nm.

[0050] Preferably, the thickness of the perovskite active layer is 300 nm to 1000 nm, for example, 300 nm, 500 nm, 600 nm, 800 nm or 1000 nm.

[0051] In a third aspect, the present invention provides a perovskite solar cell, wherein the perovskite solar cell comprises the composite perovskite film as described in the second aspect.

[0052] Preferably, the perovskite solar cell further includes a transparent conductive layer, an electron transport layer and a top electrode layer.

[0053] Preferably, the perovskite solar cell comprises a transparent conductive layer, a nickel oxide substrate layer, a SAM modified layer, a perovskite active layer, an electron transport layer and a top electrode layer which are stacked in sequence.

[0054] Compared with the prior art, the present invention has the following beneficial effects:

[0055] (1) The method of the present invention can improve the uniformity of the dispersion of the SAM material on the nickel oxide layer and enhance the adhesion of the SAM material. Through a suitable preparation process, the wettability of the perovskite on the SAM single film is greatly improved, the generation of perovskite defects is reduced, and the quality of the perovskite film is further improved.

[0056] (2) The composite perovskite film of the present invention can produce a large-area perovskite solar module with a filling factor FF of more than 68.81% and an energy conversion efficiency of more than 16.14% while ensuring the basic performance of short-circuit current and open-circuit voltage. By adjusting the preparation conditions and parameters, the filling factor FF of the perovskite solar cell can reach more than 76.16% and the energy conversion efficiency can reach more than 16.41%. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] Figure 1 It is a flow diagram of the composite perovskite film provided in an embodiment of the present invention, wherein a is a material table, b is a manipulator, c is a coater, d is a first vacuum dryer, e is a second vacuum dryer, f is an annealing furnace, and 1-10 are specific operation sequences, specifically, 1 is loading by the manipulator, 2 is the first loading of the coater, 3 is the first unloading of the coater, 4 is loading of the first vacuum dryer, 5 is unloading of the first vacuum dryer, 6 is the second loading of the coater, 7 is the second unloading of the coater, 8 is loading of the second vacuum dryer, 9 is unloading of the second vacuum dryer, 10 is unloading of the manipulator, and 11 is feeding of the annealing furnace. DETAILED DESCRIPTION

[0058] The technical solution of the present invention is further described below by specific implementation methods. It should be understood by those skilled in the art that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0059] Example 1

[0060] This embodiment provides a composite perovskite film, wherein the composite perovskite film is formed by Figure 1 The process shown produces:

[0061] The material on the material platform a is grabbed by the manipulator b through the manipulator loading 1, and is placed in the coating machine c for coating through the coating machine first loading 2, and then the coating machine first unloading 3 is performed, and it is transferred to the first vacuum dryer d for the first vacuum drying, and after drying, the first vacuum dryer unloading 5 is performed, and the coating machine second loading 6 is placed in the coating machine c for coating, and then the coating machine second unloading 7 is performed, and it is transferred to the second vacuum dryer e for the second vacuum drying, and after drying, the second vacuum dryer unloading 9 is performed, and the material is transferred to the material platform a through the manipulator unloading 10, and then transferred to the annealing furnace f for annealing treatment through the annealing furnace feeding 11. In the above steps, the manipulator b is used to transfer from each device.

[0062] The specific preparation method of the composite perovskite film is as follows:

[0063] (1) coating a SAM precursor solution on a nickel oxide substrate through a slit coating at a speed of 60 mm / s, a liquid injection rate of 160 μL / s, and a distance between the coating head and the substrate of 200 μm, and vacuum drying for 60 s at a chamber pressure of 100 Pa to form a SAM modified layer, wherein the solvent of the SAM precursor solution is DMF:acetonitrile:DMSO:DMI=4:2:1:1 in volume ratio, the mass concentration of 2PACz in the SAM precursor solution is 0.5 g / L, and the volume concentration of KH570 is 0.5 mL / L;

[0064] (2) The perovskite precursor solution is coated on the SAM modified layer through a slit coating at a speed of 60 mm / s, a liquid injection rate of 160 μL / s, and a distance between the coating head and the substrate of 200 μm, and vacuum dried for 100 s at a chamber pressure of 100 Pa to form a perovskite light absorbing layer to obtain a precursor film, wherein the solvent of the perovskite precursor solution is DMF:acetonitrile:DMSO:DMI=4:2:1:1 in volume ratio, and the solute in the perovskite precursor solution is (Cs 0.05 (FA 0.98 MA 0.02 ) 0.95 Pb(I0.98 Br 0.02 )3, concentration is 1.2mol / L;

[0065] (3) Annealing the precursor film at 180° C. at a conveying speed of 0.2 m / min for 30 min to obtain the composite perovskite film.

[0066] In the composite perovskite film, the thickness of the nickel oxide base layer is 10 nm, the thickness of the SAM modified layer is 3 nm, and the thickness of the perovskite active layer is 350 nm.

[0067] Example 2

[0068] This embodiment provides a composite perovskite film, wherein the composite perovskite film is formed by Figure 1 The process shown produces:

[0069] The material on the material platform a is grabbed by the manipulator b through the manipulator loading 1, and is placed in the coating machine c for coating through the coating machine first loading 2, and then the coating machine first unloading 3 is performed, and it is transferred to the first vacuum dryer d for the first vacuum drying, and after drying, the first vacuum dryer unloading 5 is performed, and the coating machine second loading 6 is placed in the coating machine c for coating, and then the coating machine second unloading 7 is performed, and it is transferred to the second vacuum dryer e for the second vacuum drying, and after drying, the second vacuum dryer unloading 9 is performed, and the material is transferred to the material platform a through the manipulator unloading 10, and then transferred to the annealing furnace f for annealing treatment through the annealing furnace feeding 11. In the above steps, the manipulator b is used to transfer from each device.

[0070] The specific preparation method of the composite perovskite film is as follows:

[0071] (1) coating a SAM precursor solution on a nickel oxide substrate through a slit coating at a speed of 10 mm / s, a liquid injection rate of 80 μL / s, and a distance of 50 μm between the coating head and the substrate, and vacuum drying for 10 s at a chamber pressure of 10 Pa to form a SAM modified layer, wherein the solvent of the SAM precursor solution is a volume ratio of DMF:acetonitrile:DMSO:DMI=3:2:2:1, the mass concentration of MeO-2PACz in the SAM precursor solution is 0.1 g / L, and the volume concentration of KH590 is 0.1 mL / L;

[0072] (2) The perovskite precursor solution is coated on the SAM modified layer through a slit coating at a speed of 30 mm / s, a liquid injection rate of 200 μL / s, and a distance between the coating head and the substrate of 150 μm, and vacuum dried for 50 seconds at a chamber pressure of 0.1 Pa to form a perovskite light absorbing layer to obtain a precursor film, wherein the solvent of the perovskite precursor solution is DMF:acetonitrile:DMSO:DMI=3:2:2:1 in a volume ratio, and the solute in the perovskite precursor solution is (Cs 0.05 (FA 0.98 MA 0.02 ) 0.95 Pb(I 0.98 Br 0.02 )3, concentration is 0.2mol / L;

[0073] (3) Annealing the precursor film at 100° C. at a conveying speed of 0.1 m / min for 60 min to obtain the composite perovskite film.

[0074] In the composite perovskite film, the thickness of the nickel oxide base layer is 5 nm, the thickness of the SAM modified layer is 5 nm, and the thickness of the perovskite active layer is 500 nm.

[0075] Example 3

[0076] This embodiment provides a composite perovskite film, wherein the composite perovskite film is formed by Figure 1 The process shown produces:

[0077] The material on the material platform a is grabbed by the manipulator b through the manipulator loading 1, and is placed in the coating machine c for coating through the coating machine first loading 2, and then the coating machine first unloading 3 is performed, and it is transferred to the first vacuum dryer d for the first vacuum drying, and after drying, the first vacuum dryer unloading 5 is performed, and the coating machine second loading 6 is placed in the coating machine c for coating, and then the coating machine second unloading 7 is performed, and it is transferred to the second vacuum dryer e for the second vacuum drying, and after drying, the second vacuum dryer unloading 9 is performed, and the material is transferred to the material platform a through the manipulator unloading 10, and then transferred to the annealing furnace f for annealing treatment through the annealing furnace feeding 11. In the above steps, the manipulator b is used to transfer from each device.

[0078] The specific preparation method of the composite perovskite film is as follows:

[0079] (1) coating a SAM precursor solution on a nickel oxide substrate through a slit coating at a speed of 60 mm / s, a liquid injection rate of 300 μL / s, and a distance between the coating head and the substrate of 200 μm, and vacuum drying for 30 seconds at a chamber pressure of 20 Pa to form a SAM modified layer, wherein the solvent of the SAM precursor solution is DMF:acetonitrile:DMSO:DMI=3:2:2:1 in volume ratio, the mass concentration of MeO-2PACz in the SAM precursor solution is 10 g / L, and the volume concentration of KH550 is 10 mL / L;

[0080] (2) The perovskite precursor solution is coated on the SAM modified layer through a slit coating at a speed of 60 mm / s, a liquid injection rate of 300 μL / s, and a distance between the coating head and the substrate of 200 μm, and vacuum dried for 50 seconds at a chamber pressure of 1 Pa to form a perovskite light absorbing layer to obtain a precursor film, wherein the solvent of the perovskite precursor solution is DMF:acetonitrile:DMSO:DMI=3:2:2:1 in a volume ratio, and the solute in the perovskite precursor solution is (Cs 0.05 (FA 0.98 MA 0.02 ) 0.95 Pb(I 0.98 Br 0.02 )3, concentration is 1.5mol / L;

[0081] (3) Annealing the precursor film at 200° C. at a conveying speed of 1 m / min for 10 min to obtain the composite perovskite film.

[0082] In the composite perovskite film, the thickness of the nickel oxide base layer is 20 nm, the thickness of the SAM modified layer is 8 nm, and the thickness of the perovskite active layer is 700 nm.

[0083] Example 4

[0084] The only difference between this embodiment and embodiment 1 is that the vacuum drying time in step (1) is 5 s, and the other conditions and parameters are exactly the same as those in embodiment 1.

[0085] Example 5

[0086] The only difference between this embodiment and embodiment 1 is that the vacuum drying time in step (1) is 150 s, and the other conditions and parameters are exactly the same as those in embodiment 1.

[0087] Example 6

[0088] The only difference between this embodiment and embodiment 1 is that the volume concentration of the silane coupling agent in step (1) is 0.05 mL / L, and the other conditions and parameters are exactly the same as those in embodiment 1.

[0089] Example 7

[0090] The only difference between this embodiment and embodiment 1 is that the volume concentration of the silane coupling agent in step (1) is 15 mL / L, and the other conditions and parameters are exactly the same as those in embodiment 1.

[0091] Comparative Example 1

[0092] The only difference between this comparative example and Example 1 is that the silane coupling agent KH570 is not added, and the other conditions and parameters are exactly the same as those in Example 1.

[0093] Comparative Example 2

[0094] The only difference between this comparative example and Example 1 is that the vacuum drying treatment in step (1) is not performed, and the other conditions and parameters are exactly the same as those in Example 1.

[0095] Comparative Example 3

[0096] The only difference between this comparative example and Example 1 is that the solvent system used in step (2) is DMA:THF:NMP:DMI=3:2:2:1, that is, the solvents used in the SAM precursor solution in step (1) and the perovskite precursor solution in step (2) are different, and the other conditions and parameters are exactly the same as in Example 1.

[0097] Performance Testing:

[0098] (1) Performing the first laser scribing on the FTO substrate (P1);

[0099] (2) depositing a nickel oxide base layer on the above-mentioned base;

[0100] (3) A composite perovskite film was prepared on a nickel oxide substrate using the methods of the embodiment and the comparative example respectively;

[0101] (4) Sequentially deposit C on the perovskite substrate 60 , SnO2;

[0102] (5) performing a second laser scribing on the substrate (P2);

[0103] (6) depositing a metal electrode Cu on the above substrate;

[0104] (7) performing a third laser scribing on the substrate (P3);

[0105] (8) The fourth laser edge cleaning (P4) was performed on the above substrate to obtain a perovskite solar cell. The obtained perovskite solar cell was tested. The test results are shown in Table 1:

[0106] Table 1

[0107]

[0108]

[0109] As can be seen from Table 1, from Examples 1-7, the large-area perovskite solar module prepared by the composite perovskite film of the present invention can achieve a filling factor FF of more than 68.81% and an energy conversion efficiency of more than 16.14% while ensuring the basic performance of short-circuit current and open-circuit voltage. By adjusting the preparation conditions and parameters, the filling factor FF of the perovskite solar cell can reach more than 76.16%, and the energy conversion efficiency can reach more than 16.41%.

[0110] By comparing Example 1 with Examples 4-5, it can be seen that in the preparation process of the composite perovskite film of the present invention, the time of the vacuum drying treatment in step (1) will affect its performance. When the time of the vacuum drying treatment in step (1) is controlled within 10s to 100s, the performance of the composite perovskite film obtained is better. If the time of the vacuum drying treatment in step (1) is too short, the residual content of the non-volatile solvent in the SAM is relatively large, resulting in changes in the perovskite solvent system during the vacuum drying of the perovskite, deterioration of the crystallization quality, and reduction of component performance. If the time of the vacuum drying treatment in step (1) is too long, the residual content of the non-volatile solvent in the SAM is low, and it is difficult to play a similar compatibility role, resulting in poor interface contact between the perovskite and the NIO, thereby affecting the component performance.

[0111] By comparing Example 1 with Examples 6-7, it can be seen that in the preparation process of the composite perovskite film of the present invention, the concentration of the silane coupling agent in the SAM precursor solution in step (1) affects its performance. When the concentration of the silane coupling agent in the SAM precursor solution is controlled at 0.1 mL / L to 10 mL / L, the performance of the composite perovskite film obtained is better. If the concentration of the silane coupling agent in the SAM precursor solution is too low, the perovskite and NIO interfaces cannot be anchored over a large area through the silane coupling agent. If the concentration of the silane coupling agent in the SAM precursor solution is too high, although the contact between the nickel oxide and the perovskite interface can be improved, due to the high concentration of the deposited silane coupling agent, it acts as an insulating layer between the interfaces, affecting the transmission of photogenerated carriers and causing a significant decrease in component performance.

[0112] By comparing Example 1 with Comparative Examples 1-2, it can be seen that in the preparation process of the composite perovskite film of the present invention, after the SAM precursor solution is applied, the phosphonic acid group of the SAM material itself will form a hydrogen bond or a covalent bond with the reactive group in the silane coupling agent, and the hydrolysis group in the silane coupling agent will preferentially react with the water molecules attached to the surface of the nickel oxide, and in the subsequent annealing process, a condensation reaction will occur with the hydroxyl group on the surface of the nickel oxide to form a strong Si-O-Si chemical bond to achieve uniform anchoring of the SAM and the nickel oxide, thereby reducing the defects of the SAM itself being uneven and having poor adhesion in the solvent system.

[0113] By comparing Example 1 and Comparative Example 3, it can be seen that the SAM precursor solution of the present invention and the perovskite use the same solvent, and the solvent residue in the SAM semi-dry film is achieved by controlling the parameters of the drying process. At the same time, the perovskite precursor coating is directly performed without annealing. Since the solvent residue in the SAM semi-dry film is controlled by controlling the drying process, and the perovskite precursor uses the same solvent system, the wettability of the perovskite on the SAM single film is greatly improved under the effect of the principle of like dissolves like, the generation of perovskite defects is reduced, and the film quality of the perovskite is further improved.

[0114] The applicant declares that the above is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention shall fall within the protection scope and disclosure scope of the present invention.

Claims

1. A method for preparing a composite perovskite film, characterized in that: The preparation method comprises the following steps: (1) coating a SAM precursor solution on a nickel oxide substrate and forming a SAM modified layer through a first drying process; (2) coating a perovskite precursor solution on the SAM modified layer, and obtaining a precursor film through a second drying process; (3) annealing the precursor film to obtain the composite perovskite film; The solute of the SAM precursor solution includes a SAM material and a silane coupling agent, and the solvent of the SAM precursor solution and the perovskite precursor solution are the same.

2. The preparation method according to claim 1, characterized in that The solvent of the SAM precursor solution in step (1) includes a volatile solvent and / or a non-volatile solvent; Preferably, the volatile solvent is any one or a combination of at least two of N,N-dimethylformamide, 2-methoxyethanol, ethanol, tetrahydrofuran, N,N-dimethylacetamide, acetonitrile or γ-butyrolactone; Preferably, the non-volatile solvent includes any one of dimethyl sulfoxide, N-methylpyrrolidone or dimethyl-2-imidazolidinone, or a combination of at least two thereof; Preferably, the SAM material includes any one of 2-(9H-carbazole-9-yl)ethylphosphonic acid, 4-(3,6-dimethyl-9H-carbazole-9-yl)butylphosphonic acid, 4-(7H-dibenzocarbazole-7-yl)butylphosphonic acid or 2-(3,6-dimethoxy-9H-carbazole-9-yl)ethylphosphonic acid or a combination of at least two thereof; Preferably, the silane coupling agent includes any one or a combination of at least two of γ-aminopropyltriethoxysilane, 3-(2,3-epoxypropyloxy)propyltrimethoxysilane, 3-(trimethoxysilyl)propyl methacrylate, γ-mercaptopropyltrimethoxysilane or vinyltrimethoxysilane; Preferably, in the SAM precursor solution of step (1), the mass concentration of the SAM material is 0.1 g / L to 10 g / L; Preferably, in the SAM precursor solution of step (1), the volume concentration of the silane coupling agent is 0.1 mL / L to 10 mL / L.

3. The preparation method according to claim 1 or 2, characterized in that: The coating method in step (1) includes slit coating; Preferably, the slit coating speed is 10 mm / s to 60 mm / s; Preferably, the injection speed of the slit coating is 80 μL / s to 300 μL / s; Preferably, during the slit coating process, the distance between the coating head and the substrate is 50 μm to 200 μm; Preferably, the first drying process in step (1) comprises vacuum drying; Preferably, the chamber pressure of the first drying process in step (1) is 0.1 Pa to 100 Pa; Preferably, the vacuuming time of the first drying treatment in step (1) is 10s to 100s.

4. The preparation method according to any one of claims 1 to 3, characterized in that: The chemical formula of the solute in the perovskite precursor solution in step (2) is Cs x (FA y MA 1-y )1-xPb(I z Br 1-z )3, x is 0 to 1 but not 0, y is 0 to 1 but not 0, z is 0 to 1 but not 0; Preferably, the solvent of the perovskite precursor solution in step (2) comprises a volatile solvent and / or a non-volatile solvent; Preferably, the volatile solvent is any one or a combination of at least two of N,N-dimethylformamide, 2-methoxyethanol, ethanol, tetrahydrofuran, N,N-dimethylacetamide, acetonitrile or γ-butyrolactone; Preferably, the non-volatile solvent includes any one of dimethyl sulfoxide, N-methylpyrrolidone or dimethyl-2-imidazolidinone, or a combination of at least two thereof; Preferably, the molar concentration of the perovskite precursor solution in step (2) is 0.2 mol / L to 1.5 mol / L.

5. The preparation method according to any one of claims 1 to 4, characterized in that: The coating method in step (2) includes slit coating; Preferably, the slit coating speed is 10 mm / s to 60 mm / s; Preferably, the injection speed of the slit coating is 80 μL / s to 300 μL / s; Preferably, during the slit coating process, the distance between the coating head and the substrate is 50 μm to 200 μm; Preferably, the second drying process in step (2) comprises vacuum drying; Preferably, the chamber pressure of the second drying process in step (2) is 0.1Pa to 100Pa; Preferably, the vacuuming time of the second drying treatment in step (2) is 10s to 100s.

6. The preparation method according to any one of claims 1 to 5, characterized in that: The temperature of the annealing treatment in step (3) is 100° C. to 200° C.; Preferably, the annealing treatment time in step (3) is 10 min to 60 min; Preferably, the transmission speed of the annealing treatment in step (3) is 0.1 m / min to 1 m / min.

7. A composite perovskite film, characterized in that: The composite perovskite film is prepared by the preparation method according to any one of claims 1 to 6.

8. The composite perovskite film according to claim 7, characterized in that: The composite perovskite film comprises a nickel oxide base layer, a SAM modified layer and a perovskite active layer which are stacked in sequence; Preferably, the thickness of the nickel oxide base layer is 5nm to 100nm; Preferably, the thickness of the SAM modified layer is 1 nm to 100 nm; Preferably, the thickness of the perovskite active layer is 300 nm to 1000 nm.

9. A perovskite solar cell, characterized in that: The perovskite solar cell comprises the composite perovskite thin film as claimed in claim 8.

10. The perovskite solar cell according to claim 9, characterized in that: The perovskite solar cell also includes a transparent conductive layer, an electron transport layer and a top electrode layer; Preferably, the perovskite solar cell comprises a transparent conductive layer, a nickel oxide substrate layer, a SAM modified layer, a perovskite active layer, an electron transport layer and a top electrode layer which are stacked in sequence.

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