Perovskite passivation method based on ink-jet printing technology and laminated solar cell

Abstract

The invention discloses a perovskite passivation method based on an ink-jet printing process and a laminated solar cell, and the method comprises the steps: dissolving a zwitterionic surfactant in an organic solvent, and mixing the zwitterionic surfactant with a passivator to form a passivator solution; coating the perovskite precursor solution on the surface of the substrate to form a perovskite wet film; spin-coating the perovskite wet film with a metal halide salt solution, and carrying out annealing treatment to obtain a perovskite layer; depositing a passivating agent solution on the surface of the perovskite layer in an ink-jet printing manner, and performing integral annealing treatment to form a perovskite passivation layer; therefore, the surface roughness of the perovskite is reduced, uniform deposition of a subsequent passivation layer is facilitated, meanwhile, a metal cation part can be coordinated with lead ions in the perovskite thin film, a halogen anion part can fill up iodine vacancies in the perovskite, the defect density in the perovskite thin film is reduced, non-radiation loss is reduced, and the performance of the perovskite thin film is improved. And unbalanced transmission of carriers in the vertical direction is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of solar cells, and in particular to a perovskite passivation method and a tandem solar cell based on an inkjet printing process. Background Art

[0002] In recent years, the technology of perovskite / silicon tandem solar cells has developed rapidly, and its efficiency has increased from 13.7% to 34.6% today. This is due to its wider solar spectrum absorption range and higher open-circuit voltage output value. Therefore, perovskite / silicon tandem solar cells are considered to be a new photovoltaic technology that is most promising to fundamentally improve the photoelectric conversion efficiency and significantly reduce the cost of solar power generation.

[0003] The preparation of the passivation layer of perovskite / silicon tandem solar cells is a key step affecting the efficiency and long-term stability of the entire cell. Compared with the one-step method, the surface of the perovskite film prepared by the two-step method is usually rougher, which seriously hinders the uniform deposition of the passivation layer. At the same time, the existing preparation methods are difficult to meet the requirements of large-area and high-speed perovskite film passivation. Spin coating, as a common preparation method, has the characteristics of simple operation, etc. However, this method seriously wastes materials and is not suitable for industrial continuous production. For slot die coating, due to the narrow depth of the coating head (generally in the range of a few micrometers), the surface height fluctuation of the substrate is likely to cause scratches or unevenness of the perovskite film. Inkjet printing, as a non-contact technology, has the characteristics of high material utilization rate, low cost, high process efficiency, large-area preparation, and suitability for flexible substrates. However, in the inkjet printing process, due to the complex hydrodynamics and evaporation dynamics of the ink, the coffee ring effect often occurs during the drying process of the droplets. Summary of the Invention

[0004] The present invention overcomes the deficiencies of the prior art and provides a perovskite passivation method and a tandem solar cell based on an inkjet printing process.

[0005] To achieve the above object, the technical solution adopted by the present invention is as follows: A perovskite passivation method based on an inkjet printing process includes the following steps:

[0006] S1: Dissolve an amphoteric ion surfactant in an organic solvent, mix it with a passivating agent to form a passivating agent solution;

[0007] S2: Coat a perovskite precursor solution on the surface of a substrate to form a perovskite wet film;

[0008] S3: Spin coat a metal halide salt solution on the perovskite wet film and perform annealing treatment to obtain a perovskite layer;

[0009] S4: Deposit the passivating agent solution on the surface of the perovskite layer by inkjet printing and perform overall annealing treatment to form a perovskite passivation layer.

[0010] In a preferred embodiment of the present invention, in S1, the passivating agent is at least one of phenethylammonium iodide, tetrabutylammonium iodide, octylammonium iodide, piperazine iodide, propylamine hydroiodide, 1,3-diaminopropane dihydroiodide, and alkylammonium iodide; the zwitterionic surfactant is at least one of tetradecyldimethyl(3-sulfopropyl)ammonium hydroxide inner salt, N,N-dimethyl(methacryloyloxyethyl)aminopropanesulfonic acid inner salt, and dodecyldimethyl(3-sulfopropyl)ammonium hydroxide inner salt; the organic solvent is at least one of methanol, isopropanol, n-butanol, chlorobenzene, and acetonitrile.

[0011] In a preferred embodiment of the present invention, the concentration of the passivating agent is 1-10 mg / mL, and the concentration of the zwitterionic surfactant is 0.1-1 mg / mL.

[0012] In a preferred embodiment of the present invention, in S2, the substrate is at least one of ITO, FTO, AZO, PET, PEN, PI, and silicon cells.

[0013] In a preferred embodiment of the present invention, in S2, the coating method of the perovskite precursor solution is at least one of inkjet printing, spin coating, slot die coating, blade coating, spraying, and screen printing.

[0014] In a preferred embodiment of the present invention, in S3, the metal halide salt is at least one of cesium iodide, cesium chloride, cesium bromide, rubidium iodide, rubidium bromide, rubidium chloride, potassium chloride, potassium iodide, and potassium bromide.

[0015] In a preferred embodiment of the present invention, in S3, the annealing temperature is 100-150 °C, and the annealing time is 30-60 min.

[0016] In a preferred embodiment of the present invention, in S4, the inkjet printing resolution is 300-1800 dpi, the jetting frequency is 100-10000 Hz, and the droplet volume is 10-100 pL.

[0017] In a preferred embodiment of the present invention, in S4, the overall annealing temperature is 70-120 °C, and the annealing time is 5-10 min.

[0018] A tandem solar cell includes a crystalline silicon bottom cell, a tunneling layer, and a perovskite top cell. The perovskite top cell includes a first transparent electrode layer, a hole transport layer, a perovskite passivation layer, a passivation layer, an electron transport layer, a second transparent electrode layer, a metal electrode layer, and an antireflection layer.

[0019] The present invention solves the defects in the background art and has the following beneficial effects:

[0020] (1) The present invention provides a perovskite passivation method and a tandem solar cell based on an inkjet printing process. By using a metal halide salt solution to clean the surface of perovskite, it solves the problem that when preparing perovskite by the existing two-step method, the cations are washed away due to rinsing the surface of the perovskite film with pure organic solvents, resulting in the appearance of exposed PbI2 microcrystals and Pb0 substances on the surface. By supplementing metal cations different from the original perovskite cations, it promotes the reaction with perovskite to form a new surface reconstruction layer, thereby reducing the surface roughness of perovskite, facilitating the uniform deposition of the subsequent passivation layer. At the same time, part of the metal cations can coordinate with lead ions in the perovskite film, and part of the halogen anions can fill the iodine vacancies in perovskite, reducing the defect density in the perovskite film, reducing non-radiative losses, and enhancing the non-equilibrium transport of carriers in the vertical direction.

[0021] (2) The present invention provides a perovskite passivation method and a tandem solar cell based on an inkjet printing process. By introducing an amphoteric ion surfactant as an additive, it changes the surface tension of the passivating agent solution, increases the Marangoni flow effect, inhibits the coffee ring effect during the inkjet printing process, further improves the uniformity of the perovskite passivation layer. At the same time, the anionic part in the molecule can passivate the positively charged defects in the perovskite film, and the cationic part can passivate the negatively charged defects, further reducing the defect density in the perovskite absorption layer, thereby improving the passivation effect of the perovskite passivation layer. Brief Description of the Drawings

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments recorded in the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings;

[0023] Figure 1 is the preparation flow chart of the preferred Embodiment 1 of the present invention;

[0024] Figure 2 is the structural schematic diagram of the preferred Device Embodiment 1 of the present invention. Detailed Embodiments

[0025] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0026] In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. However, the present invention may be practiced in other ways than those specifically described herein. Therefore, the scope of protection of the present invention is not limited by the specific embodiments disclosed below.

[0027] In the description of the present application, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as limiting the scope of protection of the present application. In addition, the terms "first", "second", etc. are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Therefore, the features defined with "first", "second", etc. may explicitly or implicitly include one or more of such features. In the description of the present invention, unless otherwise specified, the meaning of "a plurality" is two or more.

[0028] In the description of the present application, it should be noted that unless otherwise clearly defined and limited, the terms "mounted", "connected", "coupled" shall be construed in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood through specific circumstances.

[0029] Figure 1 Shown as S1, preparing a passivating agent solution: Dissolve an amphoteric ion surfactant in an organic solvent and mix it with a passivating agent to form a passivating agent solution;

[0030] In the present invention, the passivating agent is composed of a cyclic or aromatic ammonium cation and a typical halide anion, wherein the ammonium cation can bind to the surface of the perovskite absorption layer through a vacancy or a hydrogen bond, thereby forming a thin molecular layer on the surface of the perovskite absorption layer. Specifically, the passivating agent is at least one of phenethylammonium iodide, tetrabutylammonium iodide, octylammonium iodide, piperazine iodide, propylamine hydroiodide, 1,3-diaminopropane dihydroiodide, alkylammonium iodide, and can be any one or several of the above.

[0031] In the present invention, the zwitterionic surfactant consists of an anion and a cation, and the cationic part is composed of a quaternary ammonium salt. Specifically, the zwitterionic surfactant is at least one of tetradecyldimethyl(3-sulfopropyl)ammonium hydroxide inner salt, N,N-dimethyl(methacryloyloxyethyl)aminopropanesulfonic acid inner salt, and dodecyldimethyl(3-sulfopropyl)ammonium hydroxide inner salt, and can be any one or several of the above.

[0032] In the present invention, the organic solvent is at least one of methanol, isopropanol, n-butanol, chlorobenzene, and acetonitrile; the concentration of the passivating agent is 1-10 mg / mL. By adjusting the concentration of the passivating agent solution, the best balance can be achieved among the evaporation rate, crystallization rate, and film thickness of the passivating agent solution to achieve the best passivation effect.

[0033] In the present invention, the concentration of the zwitterionic surfactant is 0.1-1 mg / mL. By controlling the concentration of the zwitterionic surfactant, the surface tension of the passivating agent solution is changed to inhibit the formation of the coffee ring.

[0034] S2. Prepare the perovskite layer: Provide a substrate, and coat a perovskite precursor solution on the surface of the substrate by a solution method to form a perovskite wet film;

[0035] In the present invention, the substrate is at least one of ITO, FTO, AZO, PET, PEN, PI, and silicon cells, and can be any one or several of the above.

[0036] Specifically, the solution method is a preparation technology that converts the precursor substances in the solution into a solid film through a liquid-phase chemical reaction. The precursor solution is usually formed by mixing a compound of the target material with a suitable solvent. Through a specific deposition process, it is uniformly coated on the surface of the substrate, and then the solvent is evaporated by physical or chemical means to form a solid film.

[0037] In the present invention, the coating method of the perovskite precursor solution is at least one of inkjet printing, spin coating, slot coating, blade coating, spraying, and screen printing, and can be any one or several of the above.

[0038] S3. Clean the surface of the perovskite layer: Spin-coat a metal halide salt solution on the perovskite wet film, and after annealing, form a perovskite layer with a smooth surface;

[0039] In the present invention, the metal halide is at least one of cesium iodide, cesium chloride, cesium bromide, rubidium iodide, rubidium bromide, rubidium chloride, potassium chloride, potassium iodide, and potassium bromide.

[0040] In the present invention, during the annealing process, the annealing temperature is controlled to be 100 - 150 °C, and the annealing time is 30 - 60 min. The annealing treatment can cause the organic solvent to volatilize rapidly, thereby promoting the formation of the perovskite absorption layer.

[0041] S4. Prepare a passivation layer: Deposit the passivation agent solution on the surface of the perovskite layer by inkjet printing, and perform annealing treatment after printing to form a perovskite passivation layer.

[0042] Specifically, in the actual operation process, the process of inkjet printing the passivation agent solution includes: (1) Place the substrate coated with the perovskite absorption layer on the inkjet printer and adjust the distance from the nozzle module of the inkjet printer; (2) Inject the passivation agent solution into the ink cartridge of the inkjet printer; (3) Set the inkjet printing parameters and then perform inkjet printing.

[0043] Furthermore, the inkjet printing parameters of the passivation agent solution are set as follows: the printing resolution is 300 - 1800 dpi, the ejection frequency is 100 - 10000 Hz, and the droplet volume is 10 - 100 pL. By optimizing the inkjet printing parameters, the thickness of the passivation layer is adjusted to improve the passivation effect of the perovskite absorption layer.

[0044] In the present invention, the annealing temperature of the passivation layer is 70 - 120 °C, and the annealing time is 5 - 10 min.

[0045] An embodiment of the present invention provides a method for preparing a perovskite / silicon tandem solar cell based on an inkjet printing process. The structural schematic diagram is as Figure 2 shown. The specific structure from bottom to top is in sequence: a crystalline silicon bottom cell, a first transparent electrode layer, a hole transport layer, a perovskite layer, a passivation layer, an electron transport layer, a buffer layer, a second transparent electrode layer, a metal electrode layer, and an antireflection layer.

[0046] It should be noted that the preparation process of the above perovskite / silicon tandem solar cell is as follows: (1) Provide a crystalline silicon bottom cell; (2) Prepare a first transparent electrode layer; (3) Prepare a hole transport layer; (4) Prepare a perovskite thin film; (5) Prepare a passivation layer, and the specific process refers to the introduction in S1 and S3; (6) Prepare an electron transport layer; (7) Prepare a buffer layer; (8) Prepare a second transparent electrode layer; (9) Prepare a metal electrode; (10) Prepare an antireflection layer.

[0047] Specifically, the specific materials and preparation methods of the crystalline silicon bottom cell, the first transparent electrode layer, the hole transport layer, the perovskite layer, the electron transport layer, the buffer layer, the second transparent electrode layer, the metal electrode layer, and the antireflection layer are not limited, and existing materials and existing preparation processes can be used.

[0048] Example 1

[0049] This embodiment provides a perovskite passivation method based on an inkjet printing process, which includes the following steps:

[0050] (1) Dissolve phenethylammonium iodide and N,N-dimethyl(methacryloyloxyethyl)aminopropylsulfobetaine in isopropanol, heat and stir at 60 °C for 2 h to form a passivating agent solution with a concentration of 3 mg / mL. Filter it with a 0.22 μm filter membrane before use, wherein the concentration of N,N-dimethyl(methacryloyloxyethyl)aminopropylsulfobetaine is 0.1 mg / mL.

[0051] (2) Use the spin-coating method to coat the perovskite precursor solution on the surface of transparent conductive glass ITO. The specific spin-coating process is as follows: First, spin-coat the PbI2 solution at 2000 rpm for 30 s and anneal at 70 °C for 1 min. Then, spin-coat the FAI solution at 2500 rpm for 10 s to form a perovskite wet film.

[0052] (3) Dynamically spin-coat the cesium bromide solution onto the perovskite wet film at a spin-coating speed of 2500 rpm, and then anneal at 150 °C for 40 min to form a perovskite absorption layer.

[0053] (4) Place the ITO coated with the perovskite layer on an inkjet printer, adjust the distance between the nozzle and the ITO to 1 mm. Then, inject the passivating agent solution into the inkjet printer cartridge, set the printing resolution to 1200 dpi, set the droplet volume of the printing nozzle to 10 pL, and set the ejection frequency to 5000 Hz to form a passivation layer wet film. Immediately place it on a hot stage and anneal at 100 °C for 10 min.

[0054] Example 2

[0055] This embodiment provides a perovskite passivation method based on an inkjet printing process. The difference from Example 1 is only that: in step (1), the concentration of N,N-dimethyl(methacryloyloxyethyl)aminopropylsulfobetaine is 0.5 mg / mL. The specific steps are as follows:

[0056] (1) Dissolve phenethylammonium iodide and N,N-dimethyl(methacryloyloxyethyl)aminopropylsulfobetaine in isopropanol, heat and stir at 60 °C for 2 h to form a passivating agent solution with a concentration of 3 mg / mL. Filter it with a 0.22 μm filter membrane before use, wherein the concentration of N,N-dimethyl(methacryloyloxyethyl)aminopropylsulfobetaine is 1 mg / mL.

[0057] (2) Use the spin-coating method to coat the perovskite precursor solution on the surface of transparent conductive glass ITO. The specific spin-coating process is as follows: First, spin-coat the PbI2 solution at 2000 rpm for 30 s and anneal at 70 °C for 1 min. Then, spin-coat the FAI solution at 2500 rpm for 10 s to form a perovskite wet film.

[0058] (3) The cesium bromide solution was dynamically spin-coated onto the perovskite wet film at a spin-coating speed of 2500 rpm, and then annealed at 150 °C for 40 min to form a perovskite absorption layer.

[0059] (4) The ITO coated with the perovskite layer was placed on an inkjet printer. The distance between the nozzle and the ITO was adjusted to 1 mm. Then the passivating agent solution was injected into the inkjet printer cartridge. The printing resolution was set to 1200 dpi, the droplet volume of the printing nozzle was set to 10 pL, and the ejection frequency was set to 5000 Hz to form a wet passivation layer film. Immediately afterwards, it was placed on a hot stage and annealed at 100 °C for 10 min.

[0060] Example 3

[0061] This example provides a perovskite passivation method based on an inkjet printing process. The difference from Example 1 is only that: in step (1), the concentration of N,N-dimethyl(methacryloyloxyethyl)aminopropylsulfonic acid inner salt is 1 mg / mL. The specific steps are as follows:

[0062] (1) Phenethylammonium iodide and N,N-dimethyl(methacryloyloxyethyl)aminopropylsulfonic acid inner salt were dissolved in isopropanol and heated with stirring at 60 °C for 2 h to form a passivating agent solution with a concentration of 3 mg / mL. Before use, it was filtered through a 0.22-μm filter membrane, wherein the concentration of N,N-dimethyl(methacryloyloxyethyl)aminopropylsulfonic acid inner salt was 1 mg / mL.

[0063] (2) The perovskite precursor solution was spin-coated onto the surface of the transparent conductive glass ITO by the spin-coating method. The specific spin-coating process was as follows: First, the PbI2 solution was spin-coated at 2000 rpm for 30 s and annealed at 70 °C for 1 min. Then the FAI solution was spin-coated at 2500 rpm for 10 s to form a perovskite wet film.

[0064] (3) The cesium bromide solution was dynamically spin-coated onto the perovskite wet film at a spin-coating speed of 2500 rpm, and then annealed at 150 °C for 40 min to form a perovskite absorption layer.

[0065] (4) The ITO coated with the perovskite layer was placed on an inkjet printer. The distance between the nozzle and the ITO was adjusted to 1 mm. Then the passivating agent solution was injected into the inkjet printer cartridge. The printing resolution was set to 1200 dpi, the droplet volume of the printing nozzle was set to 10 pL, and the ejection frequency was set to 5000 Hz to form a wet passivation layer film. Immediately afterwards, it was placed on a hot stage and annealed at 100 °C for 10 min.

[0066] Example 4

[0067] This embodiment provides a perovskite passivation method based on an inkjet printing process, which is only different from Embodiment 1 in that: in step (3), the cesium bromide solution is replaced with a rubidium chloride solution. The specific steps are as follows:

[0068] (1) Dissolve phenethylammonium iodide and N,N-dimethyl(methacryloyloxyethyl)aminopropylsulfonic acid inner salt in isopropanol, heat and stir at 60 °C for 2 h to form a passivator solution with a concentration of 3 mg / mL, and filter it with a 0.22 μm filter membrane before use. Among them, the concentration of N,N-dimethyl(methacryloyloxyethyl)aminopropylsulfonic acid inner salt is 1 mg / mL.

[0069] (2) Coating the perovskite precursor solution on the surface of the transparent conductive glass ITO by spin coating. The specific spin coating process is as follows: First, spin coat the PbI2 solution at 2000 rpm for 30 s and anneal at 70 °C for 1 min, and then spin coat the FAI solution at 2500 rpm for 10 s to form a perovskite wet film.

[0070] (3) Dynamically spin coat the rubidium chloride solution onto the perovskite wet film at a spin coating speed of 2500 rpm, and then anneal at 100 °C for 40 min to form a perovskite absorption layer.

[0071] (4) Place the ITO coated with the perovskite layer on an inkjet printer, adjust the distance between the nozzle and the ITO to 1 mm, then inject the passivator solution into the inkjet printer cartridge, set the printing resolution to 1200 dpi, set the droplet volume of the printing nozzle to 10 pL, and set the ejection frequency to 5000 Hz to form a passivation layer wet film, and then immediately place it on a hot stage and anneal at 100 °C for 10 min.

[0072] Comparative Example 1

[0073] This comparative example provides a perovskite passivation method based on an inkjet printing process, which is only different from Embodiment 1 in that: N,N-dimethyl(methacryloyloxyethyl)aminopropylsulfonic acid inner salt is not added in step (1). The specific steps are as follows:

[0074] (1) Dissolve phenethylammonium iodide in isopropanol, heat and stir at 60 °C for 2 h to form a passivator solution with a concentration of 3 mg / mL, and filter it with a 0.22 μm filter membrane before use.

[0075] (2) Coating the perovskite precursor solution on the surface of the transparent conductive glass ITO by spin coating. The specific spin coating process is as follows: First, spin coat the PbI2 solution at 2000 rpm for 30 s and anneal at 70 °C for 1 min, and then spin coat the FAI solution at 2500 rpm for 10 s to form a perovskite wet film.

[0076] (3) The cesium bromide solution was spin-coated onto the perovskite wet film dynamically at a spin-coating speed of 2500 rpm, and then annealed at 150 °C for 40 min to form a perovskite absorption layer.

[0077] (4) The ITO coated with the perovskite layer was placed on an inkjet printer. The distance between the nozzle and the ITO was adjusted to 1 mm. Then the passivating agent solution was injected into the inkjet printer cartridge. The printing resolution was set to 1200 dpi, the droplet volume of the printing nozzle was set to 10 pL, and the ejection frequency was set to 5000 Hz to form a wet passivation layer film. Immediately afterwards, it was placed on a hot stage and annealed at 100 °C for 10 min.

[0078] Comparative Example 2

[0079] This comparative example provides a perovskite passivation method based on an inkjet printing process. The difference from Example 1 is only that: the step (3) of coating the cesium bromide solution is not adopted. The specific steps are as follows:

[0080] (1) Phenethylammonium iodide and N,N-dimethyl(methacryloyloxyethyl)aminopropylsulfobetaine were dissolved in isopropanol and heated and stirred at 60 °C for 2 h to form a passivating agent solution with a concentration of 3 mg / mL. Before use, it was filtered with a 0.22 μm filter membrane, wherein the concentration of N,N-dimethyl(methacryloyloxyethyl)aminopropylsulfobetaine was 0.1 mg / mL.

[0081] (2) The perovskite precursor solution was spin-coated onto the surface of the transparent conductive glass ITO by the spin-coating method. The specific spin-coating process was as follows: First, the PbI2 solution was spin-coated at 2000 rpm for 30 s and annealed at 70 °C for 1 min. Then the FAI solution was spin-coated at 2500 rpm for 10 s and annealed at 150 °C for 40 min to form a perovskite absorption layer.

[0082] (3) The ITO coated with the perovskite layer was placed on an inkjet printer. The distance between the nozzle and the ITO was adjusted to 1 mm. Then the passivating agent solution was injected into the inkjet printer cartridge. The printing resolution was set to 1200 dpi, the droplet volume of the printing nozzle was set to 10 pL, and the ejection frequency was set to 5000 Hz to form a wet passivation layer film. Immediately afterwards, it was placed on a hot stage and annealed at 100 °C for 10 min.

[0083] Device Example 1

[0084] This example provides a preparation method of a perovskite tandem solar cell, including the following steps:

[0085] (1) A 25 mm × 25 mm HJT crystalline silicon cell was selected as the bottom cell.

[0086] (2) An ITO layer was deposited on the bottom cell by magnetron sputtering. The radio frequency power was 90 W and the deposition thickness was 100 nm.

[0087] (3) Deposit Me-4PACz as the hole transport layer on the ITO layer by spin coating at a spin coating speed of 4000 rpm, a spin coating time of 30 s, an annealing temperature of 100 °C, and an annealing time of 10 min. Note: [4-(3,6-dimethyl-9H-carbazol-9-yl)butyl]phosphonic acid (Me-4PACz).

[0088] (4) Prepare the perovskite layer by spin coating. The specific spin coating process is as follows: First, spin coat the PbI2 solution at 2000 rpm for 30 s and anneal at 70 °C for 1 min. Subsequently, spin coat the FAI solution at 2500 rpm for 10 s and anneal at 150 °C for 40 min to form the perovskite absorption layer.

[0089] (5) Prepare the perovskite passivation layer using the method of Example 1.

[0090] (6) Deposit a 16-nm C60 layer as the electron transport layer on the perovskite passivation layer by evaporation, and the deposition rate is

[0091] (7) Deposit a 20-nm SnO2 layer as the buffer layer on the electron transport layer by atomic layer deposition. The precursor material is tetra(dimethylamino)tin (TDMASn). The pulse time of TDMASn is 1.6 s, the purge time is 5 s, the pulse time of H2O is 1 s, and the purge time is 5 s.

[0092] (8) Deposit a 45-nm IZO as the top electrode on the buffer layer by magnetron sputtering with a radio frequency power of 90 W.

[0093] (9) Prepare 200-nm Ag as the metal electrode by thermal evaporation, and the deposition rate is

[0094] (10) Prepare 100-nm MgF2 as the antireflection layer by thermal evaporation, and the deposition rate is

[0095] Device Example 2

[0096] The difference from Device Example 1 is only that: the method for preparing the perovskite passivation layer in step (5) is different. Device Example 2 is prepared using the method of Example 2.

[0097] Device Example 3

[0098] The difference from Device Example 1 is only that: the method for preparing the perovskite passivation layer in step (5) is different. Device Example 3 is prepared using the method of Example 3.

[0099] Device Comparative Example 1

[0100] The difference from Device Example 1 is only that: the method for preparing the perovskite passivation layer in step (5) is different, and Device Comparative Example 1 is prepared by the method of Comparative Example 1.

[0101] Device Comparative Example 2

[0102] The difference from Device Example 1 is only that: the method for preparing the perovskite passivation layer in step (5) is different, and Device Comparative Example 2 is prepared by the method of Comparative Example 2.

[0103] Experiment 1:

[0104] The efficiency of the battery devices of the device examples and device comparative examples was tested. Usually, the short-circuit current density (Jsc) was measured by current-voltage (J-V) characteristic testing. The open-circuit voltage (Voc) was obtained by measuring the J-V characteristic curve. By measuring the J-V characteristic curve, the maximum power point on the curve was found, and then the ratio of the maximum output power (Pmax) to the theoretical maximum power (Isc×Voc) was calculated, that is, FF = (Pmax) / (Isc×Voc)×100%, and then the fill factor (FF) was obtained. By measuring the values of Jsc, Voc, and FF, and the power density Pin of the incident light, substituting into PCE = (Jsc×Voc×FF) / Pin×100%, the photoelectric conversion efficiency (PCE) was obtained in this way. The test results are shown in Table 1.

[0105] Table 1 Efficiency of the battery devices obtained from the examples and device comparative examples

[0106] Group <![CDATA[Jsc (mA / cm 2 )]]> Voc (V) FF (%) PCE (%) Device Example 1 19.62 1.89 76.4 28.33 Device Example 2 19.65 1.90 76.9 28.65 Device Example 3 19.55 1.85 76.8 27.78 Device Example 4 19.47 1.87 76.9 28.01 Device Comparative Example 1 19.43 1.77 75.8 26.06 Device Comparative Example 2 19.51 1.78 75.0 26.04

[0107] It can be clearly seen from Table 1 that when the concentration of N,N-dimethyl(methacryloyloxyethyl)aminopropylsulfonic acid inner salt increases from 0.1 mg / ml to 0.5 mg / ml, the photoelectric conversion efficiency of the device increases from 28.33% to 28.65%. The increase in the concentration of N,N-dimethyl(methacryloyloxyethyl)aminopropylsulfonic acid inner salt further reduces the surface tension of the passivating agent solution and inhibits the formation of the coffee ring, thereby improving the short-circuit current Jsc, open-circuit voltage Voc, and fill factor FF. When it increases from 0.5 mg / ml to 1 mg / ml, the conversion efficiency of the device decreases to 27.78. This is because the excessive N,N-dimethyl(methacryloyloxyethyl)aminopropylsulfonic acid inner salt reacts with the perovskite to form new defects, thereby reducing the passivation effect.

[0108] As can be clearly seen from Table 1, compared with the perovskite passivation layer of Device Comparative Example 1 without N,N-dimethyl(methacryloyloxyethyl)aminopropylsulfonate inner salt, the power conversion efficiency (PCE) of the device has been significantly improved. Among them, the open-circuit voltage (Voc) has increased from 1.77 V to 1.89 V, and the fill factor has increased from 75.8% to 76.4%. The increase in Voc benefits from the passivation effect of N,N-dimethyl(methacryloyloxyethyl)aminopropylsulfonate inner salt, which realizes the defect passivation of perovskite in two ways: (1) The ester group and SO 3 2- passivate the positively charged defects. (2) The quaternary ammonium ions can passivate the negatively charged defects.

[0109] As can be clearly seen from Table 1, compared with Device Comparative Example 2, the fill factor (FF) of the device has increased from 75% to 76.4%. The FF of the battery is jointly affected by various factors such as the series and parallel resistances of the device and the defect density of the functional layer. A uniform passivation layer is beneficial to efficient charge extraction and transport, thereby reducing the series resistance and increasing the FF. This indicates that cleaning the perovskite surface with a metal halide salt solution is beneficial to the formation of a uniform passivation layer.

[0110] Based on the ideal embodiments of the present invention as inspiration, through the above description, relevant personnel can completely make various changes and modifications without departing from the technical idea of the present invention. The technical scope of the present invention is not limited to the content in the specification, and the technical scope must be determined according to the scope of the claims.

Claims

1. A perovskite passivation method based on inkjet printing process, characterized in that: The following steps are involved: S1: dissolving a zwitterionic surfactant in an organic solvent and mixing it with a passivating agent to form a passivating agent solution; S2: coating the perovskite precursor solution on the surface of the substrate to form a perovskite wet film; S3: spin coating a metal halide solution on the perovskite wet film, and performing annealing treatment to obtain a perovskite layer; S4: depositing the passivation agent solution onto the surface of the perovskite layer by inkjet printing, and performing overall annealing treatment to form a perovskite passivation layer.

2. The perovskite passivation method and laminated solar cell based on inkjet printing process according to claim 1, characterized in that: In S1, the passivator is at least one of phenethylammonium iodide, tetrabutylammonium iodide, octylamine iodide, piperazine iodide, propylamine hydroiodide, 1,3-diaminopropane dihydroiodide, and alkylammonium iodide; the zwitterionic surfactant is at least one of tetradecyldimethyl (3-sulfopropyl) ammonium hydroxide inner salt, N,N-dimethyl (methacryloyloxyethyl) aminopropanesulfonic acid inner salt, and dodecyldimethyl (3-sulfopropyl) ammonium hydroxide inner salt; and the organic solvent is at least one of methanol, isopropanol, n-butanol, chlorobenzene, and acetonitrile.

3. The perovskite passivation method and laminated solar cell based on inkjet printing process according to claim 2, characterized in that: In S1, the concentration of the passivator is 1-10 mg / mL, wherein the concentration of the zwitterionic surfactant is 0.1-1 mg / mL.

4. The perovskite passivation method and laminated solar cell based on inkjet printing process according to claim 1, characterized in that: In S2, the substrate is at least one of ITO, FTO, AZO, PET, PEN, PI, and silicon cell.

5. The perovskite passivation method and laminated solar cell based on inkjet printing process according to claim 1, characterized in that: In S2, the coating method of the perovskite precursor solution is at least one of inkjet printing, spin coating, slit coating, blade coating, spray coating, and screen printing.

6. The perovskite passivation method and laminated solar cell based on inkjet printing process according to claim 1, characterized in that: In S3, the metal halide salt is at least one of cesium iodide, cesium chloride, cesium bromide, rubidium iodide, rubidium bromide, rubidium chloride, potassium chloride, potassium iodide, and potassium bromide.

7. The perovskite passivation method and laminated solar cell based on inkjet printing process according to claim 1, characterized in that: In S3, the annealing temperature is 100-150° C., and the annealing time is 30-60 min.

8. The perovskite passivation method and laminated solar cell based on inkjet printing process according to claim 1, characterized in that: In the S4, the inkjet printing resolution is 300-1800 dpi, the jetting frequency is 100-10000 Hz, and the droplet volume is 10-100 pL.

9. The perovskite passivation method and laminated solar cell based on inkjet printing process according to claim 1, characterized in that: In the S4, the overall annealing temperature is 70-120° C., and the annealing time is 5-10 min.

10. A laminated solar cell, based on the perovskite passivation method according to any one of claims 1 to 9, comprising a crystalline silicon bottom cell, a tunneling layer and a perovskite top cell, characterized in that: The perovskite top cell includes a first transparent electrode layer, a hole transport layer, a perovskite passivation layer, a passivation layer, an electron transport layer, a second transparent electrode layer, a metal electrode layer and an anti-reflection layer.

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