Perovskite film layer and preparation method and application thereof

Abstract

The invention provides a perovskite film layer and a preparation method and application thereof. The perovskite film layer comprises a perovskite phase and an inorganic phase surrounding the perovskite phase; at the boundary interface of the perovskite phase and the inorganic phase, the edge contour of the perovskite phase is in a continuous convex shape. According to the invention, the continuous convex perovskite phase is formed at the boundary interface of the perovskite phase and the inorganic phase, so that the growth mechanism of edge perovskite crystal grains is influenced, the growth of the edge perovskite crystal grains in a specific direction is promoted, and the crystal boundary defects in the film layer are reduced; meanwhile, the continuous protrusions play an anchoring role at the edge, interface bonding can be enhanced, separation and transmission of photon-generated carriers are promoted, the charge recombination rate is reduced, a buffer layer can be used, and the edge electric leakage phenomenon is reduced; and secondly, the continuous convex perovskite phase at the boundary interface can relieve the internal stress generated in the nucleation crystallization process of the perovskite phase and prevent the generation of cracks, so that the photoelectric property and the stability of the cell device are improved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of photovoltaics, and particularly relates to a perovskite film and a preparation method and application thereof. BACKGROUND

[0002] In the past decade, organic-inorganic hybrid perovskite materials have attracted great attention in the photovoltaic (PV) field due to their excellent optoelectronic properties and solution processability. Due to their tunable band gap, perovskites can be integrated with many traditional photovoltaic materials (such as crystalline silicon, CIGS, etc.) to prepare tandem cells, thereby generating higher power conversion efficiency (PCE) than single-junction solar cells. Although the performance of single-junction cells based on the non-scalable spin-coating method has been continuously improved at the laboratory scale, the centripetal force in the spin-coating process can reduce the uniformity of solute distribution, leading to uncontrollable perovskite nucleation and crystallization of large-area thin films (>1 cm 2 ) and challenges in the commercialization of devices.

[0003] In order to achieve the uniformity of large-area perovskite thin films, a variety of solution processing techniques have been studied, such as doctor blading, spray coating, screen printing and inkjet printing (IJP), etc. Among these techniques, IJP is considered as a reliable, versatile and digital direct-writing technique, which provides a method to improve the quality of perovskite thin films by precisely adjusting small droplets and realizing large-area automated manufacturing. Generally, perovskite precursor solution is deposited on the substrate by spraying ink droplets under precise digital control, then a liquid film with the required pattern is formed, and finally solidified by post-processing. Compared with other scalable deposition techniques, IJP has a broader development prospect due to its precise droplet control and patterning function. IJP will become one of the most competitive ways for the economic and green development of perovskite optoelectronic industry.

[0004] From the perspective of compatibility with existing industries, if the cost of equipment modification of existing crystalline silicon production lines is not additionally increased, the dry-wet combined two-step method is generally adopted to prepare tandem cells on commercial-grade textured surfaces, in which the dry method refers to the evaporation of inorganic phase film, and the wet method refers to the solution deposition of organic phase thin film. However, this method still faces a series of challenges: for example, during the subsequent annealing and crystallization process, the interface reaction between the organic phase and the inorganic phase is not easy to control uniformly, which easily leads to poor crystallization quality of the perovskite phase; a large number of defects are easily formed at the edges and grain boundaries of the film, and the interface bonding strength is insufficient; at the same time, internal stress generated during the crystallization process easily causes micro-cracks and delamination, which seriously affects the performance and long-term stability of the device.

[0005] Therefore, how to reduce the grain boundary defects in the edge region of the perovskite film, enhance the interface bonding, and release the internal stress generated during the nucleation and crystallization process of the perovskite film, so as to improve the optoelectronic performance and stability of the battery device, is a technical problem to be solved. SUMMARY

[0006] In view of the deficiencies of the prior art, the present application aims to provide a perovskite film layer and a preparation method and application thereof. The present application designs a perovskite film layer with a special edge structure, uses the continuous convex perovskite phase formed at the interface between the perovskite phase and the inorganic phase to affect the growth mechanism of the edge perovskite grains, promote their growth in a specific direction, and reduce the grain boundary defects in the film layer; at the same time, the continuous convex shape plays an anchoring role at the edge, can enhance the interface bonding, promote the separation and transport of photo-generated carriers, reduce the charge recombination rate, and can be used as a buffer layer to reduce the edge leakage phenomenon; secondly, the continuous convex perovskite phase at the interface can relieve the internal stress generated in the nucleation and crystallization process of the perovskite phase, prevent cracks from occurring, thereby improving the photoelectric performance and stability of the battery device.

[0007] To achieve the object of the present application, the present application adopts the following technical solutions:

[0008] In a first aspect, the present application provides a perovskite film layer, which comprises a perovskite phase and an inorganic phase surrounding the perovskite phase.

[0009] The interface between the perovskite phase and the inorganic phase is continuous and convex.

[0010] The present application designs a perovskite film layer with a special edge structure, uses the continuous convex perovskite phase formed at the interface between the perovskite phase and the inorganic phase to affect the growth mechanism of the edge perovskite grains, promote their growth in a specific direction, and reduce the grain boundary defects in the film layer; at the same time, the continuous convex shape plays an anchoring role at the edge, can enhance the interface bonding, promote the separation and transport of photo-generated carriers, reduce the charge recombination rate, and can be used as a buffer layer to reduce the edge leakage phenomenon; secondly, the continuous convex perovskite phase at the interface can relieve the internal stress generated in the nucleation and crystallization process of the perovskite phase, prevent cracks from occurring, thereby improving the photoelectric performance and stability of the battery device.

[0011] Preferably, the continuous convex shape is periodic or quasi-periodic corrugation in the positive projection direction of the z-axis. It should be noted that the meaning of "in the positive projection direction of the z-axis" is that when the film layer is observed from the direction of viewing the film layer, the boundary line between the perovskite phase and the inorganic phase (i.e. its projection) presents a periodic or quasi-periodic corrugation pattern.

[0012] In the present application, the periodic or quasi-periodic corrugation can avoid stress concentration on one hand, and evenly distribute the stress generated in the external preparation process to the whole interface, effectively inhibit the crack initiation and propagation caused by stress concentration, on the other hand, can form an interlocking effect, significantly enhance the bonding force between the two phases, and improve the structural integrity and long-term stability of the film layer.

[0013] Preferably, the shape of the corrugation is sinusoidal or arc-like.

[0014] Preferably, the wavelength of at least one corrugation is 50-200 μm, for example, it can be 50 μm, 100 μm, 120 μm, 140 μm, 160 μm, 180 μm or 200 μm, etc.

[0015] It should be noted that the wavelength refers to the straight line distance between the lowest points of two adjacent valleys along the direction parallel to the surface of the perovskite film layer.

[0016] In the present application, the appropriate wavelength can maximize the stress release effect, while ensuring a large enough interface bonding area to stabilize the anchoring perovskite phase.

[0017] Preferably, any continuous corrugation segment in the edge profile of the perovskite phase is selected, and the average wavelength of the corrugation in the corrugation segment is 100-200 μm, for example, it can be 100 μm, 120 μm, 140 μm, 160 μm, 180 μm or 200 μm, etc.

[0018] Preferably, any continuous corrugation segment in the edge profile of the perovskite phase is selected, and the average wave height of the corrugation in the corrugation segment is 150-250 μm, for example, it can be 150 μm, 175 μm, 200 μm, 225 μm or 250 μm, etc.

[0019] It should be noted that the wave height refers to the vertical distance between the highest point of the wave peak and the lowest point of the adjacent valley in the vertical direction perpendicular to the average extension direction of the interface (i.e. the horizontal direction).

[0020] In the present application, the appropriate wave height ensures that the corrugation structure has sufficient "peak-valley" depth to generate interface interlocking force and firmly lock the perovskite grains. At the same time, sufficient wave height is the premise for guiding the deflection of cracks and consuming their expansion energy, thereby significantly improving the toughness and anti-cracking ability of the film layer.

[0021] Preferably, the average ratio of the wave height to the wavelength of the corrugation is 0.75-1.5, for example, it can be 0.75, 1, 1.25 or 1.5, etc.

[0022] In the present application, the appropriate ratio can take into account the interlocking strength between layers, the ability to release stress and crack deflection, and the ability to avoid local stress concentration, thereby simultaneously improving the mechanical strength and durability of the film layer.

[0023] Preferably, the distance between the wave crest of the corrugation and the edge of the battery is ≥400 μm, for example, it can be 400 μm, 600 μm, 800 μm, 1000 μm, 1.5 mm or 2 mm, etc. It should be noted that the edge of the battery refers to the outer edge of the inorganic phase.

[0024] Preferably, the chemical formula of the inorganic phase is BX2, wherein B includes any one or a combination of at least two of cesium ions, lead ions or tin ions, and X is a halide anion.

[0025] Preferably, the thickness of the inorganic phase is 300-800 nm, for example, it can be 300 nm, 400 nm, 500 nm, 600 nm, 700 nm or 800 nm, etc.

[0026] Preferably, the chemical formula of the perovskite phase is AB'X'3, wherein A is an organic cation, B' includes lead ions and / or tin ions, and X' is a halide anion.

[0027] Preferably, the thickness of the perovskite phase is 500-1200 nm, for example, it can be 500 nm, 600 nm, 700 nm, 800 nm, 900 nm, 1000 nm, 1100 nm or 1200 nm, etc.

[0028] In a second aspect, the present application provides a preparation method of the perovskite film layer according to the first aspect, the preparation method comprising the following steps:

[0029] Providing a substrate.

[0030] Depositing an inorganic phase film layer on the substrate.

[0031] Using inkjet printing to deposit an organic phase film layer on the inorganic phase film layer; wherein the deposition area of the organic phase film layer is smaller than the area of the inorganic phase film layer.

[0032] Performing post-processing to make the organic phase and the inorganic phase react to form a perovskite phase, and a continuous convex-shaped boundary structure is formed at the interface between the perovskite phase and the inorganic phase.

[0033] In the present application, by digitally controlling the precise positioning and quantitative deposition of droplets, accurate printing of the organic phase film layer is realized, ensuring that its deposition area is smaller than that of the inorganic phase film layer, providing a guarantee for the reservation of the edge area of the inorganic phase in the subsequent reaction; the inkjet printing method avoids the mutual interference and damage of the organic phase and the inorganic phase, effectively controls the reaction between the organic phase and the inorganic phase in a specific area, thereby forming a continuous convex-shaped boundary structure at the edge of the perovskite phase. The method provides a reliable way for the large-area preparation of high-performance and high-stability optoelectronic devices.

[0034] Preferably, the deposition method of the inorganic phase film layer comprises a dry method, and the dry method comprises a thermal evaporation method.

[0035] Preferably, the main parameters of the inkjet printing method comprise:

[0036] The viscosity of the ink droplet is 2-10 cp, for example, it can be 2 cp, 3 cp, 4 cp, 5 cp, 6 cp, 7 cp, 8 cp, 9 cp or 10 cp, etc., the printing speed of the ink droplet is 100-1000 mm / s, for example, it can be 100 mm / s, 300 mm / s, 500 mm / s, 700 mm / s, 900 mm / s or 1000 mm / s, etc., and the ejection frequency of the ink droplet is 100-1000 Hz, for example, it can be 100 Hz, 300 Hz, 500 Hz, 700 Hz, 900 Hz or 1000 Hz, etc.

[0037] By controlling the above-mentioned multiple parameters in cooperation, the present application can accurately regulate the deposition morphology, wetting behavior and diffusion depth of the organic phase ink droplet on the inorganic phase film layer, thereby guiding the controllable interfacial reaction and grain growth between the perovskite phase and the inorganic phase in the subsequent post-processing process, and finally forming a stable interface with continuous, uniform and convex interlocking structure, significantly enhancing the crystalline quality, stress release ability and long-term stability of the perovskite film layer.

[0038] Preferably, the post-processing method is annealing treatment.

[0039] In the present application, under the premise that the deposition area of the organic phase film layer is smaller than that of the inorganic phase film layer, annealing treatment is carried out, so that the perovskite grains can grow in a specific direction, reduce the grain boundary defects in the film layer, and the corrugation at the edge of the perovskite phase can play an anchoring role, enhance the interface bonding, promote the separation and transport of photo-generated carriers, and reduce the charge recombination rate.

[0040] Preferably, the temperature of the annealing treatment is 50-150℃, for example, it can be 50℃, 80℃, 100℃, 130℃ or 150℃, etc.

[0041] Preferably, the annealing process is for 5-30 minutes, for example, it can be 5 minutes, 10 minutes, 15 minutes, 20 minutes, 25 minutes or 30 minutes, etc.

[0042] In a third aspect, the present application provides a perovskite-silicon-based stacked cell, which comprises a perovskite cell and a silicon-based cell stacked from top to bottom, wherein the perovskite cell comprises the perovskite film layer as described in the first aspect.

[0043] It should be noted that the effective area of the perovskite cell can be 1 cm 2 etc.

[0044] The numerical range described in the present application includes not only the point values listed above, but also any point values between the above numerical ranges that are not listed, and the present application does not exhaustively list the specific point values included in the range for the sake of brevity and simplicity.

[0045] Compared with the prior art, the present application has the following beneficial effects:

[0046] The present application designs a perovskite film layer with a special edge structure, which utilizes the continuous convex perovskite phase formed at the interface between the perovskite phase and the inorganic phase, thereby affecting the growth mechanism of the edge perovskite grains, promoting their growth in a specific direction, and reducing the grain boundary defects in the film layer. At the same time, the continuous convex shape plays an anchoring role at the edge, which can enhance the interface bonding, promote the separation and transport of photo-generated carriers, reduce the charge recombination rate, and can be used as a buffer layer to reduce the edge leakage phenomenon. Secondly, the continuous convex perovskite phase at the interface can relieve the internal stress generated during the nucleation and crystallization of the perovskite phase, preventing cracks from occurring, thereby improving the photoelectric performance and stability of the battery device. BRIEF DESCRIPTION OF DRAWINGS

[0047] Figure 1 The structure schematic diagram of the stacked cell provided for Example 1.

[0048] Figure 2 The physical diagram of the edge portion of the stacked cell provided for Example 1 in the present application.

[0049] Figure 3 The micro edge schematic diagram of one side of the perovskite film layer provided for Example 1 in the present application.

[0050] Figure 4 The Figure 3 enlarged schematic diagram of the oval region.

[0051] Figure 5 The micro edge schematic diagram of the other side of the perovskite film layer provided for Example 1 in the present application.

[0052] Figure 6 Fig. 2 is a schematic diagram of a micro edge of one side of a perovskite film layer provided in the comparative example 1 in the present application. Figure 5 Fig. 3 is a schematic diagram of an enlarged ellipse area.

[0053] Figure 7 Fig. 4 is a schematic diagram of a micro edge of the other side of the perovskite film layer provided in the comparative example 1 in the present application.

[0054] Figure 8 Fig. 5 is a schematic diagram of a micro edge of one side of a perovskite film layer provided in the example 1 in the present application. Figure 7 Fig. 6 is a schematic diagram of an enlarged ellipse area.

[0055] Figure 9 Fig. 7 is a schematic diagram of a micro edge of the other side of the perovskite film layer provided in the example 1 in the present application.

[0056] Figure 10 Fig. 8 is a schematic diagram of a micro edge of one side of a perovskite film layer provided in the example 2 in the present application. Figure 9 Fig. 9 is a schematic diagram of an enlarged ellipse area.

[0057] Fig. 10 is a schematic diagram of a perovskite film layer provided in the example 3 in the present application. 60 1-full-textured heterojunction crystalline silicon cell; 2-ITO intermediate tunneling layer; 3-nickel oxide layer; 4-perovskite film layer; 5-C 0.08 6-SnO2 layer; 7-IZO layer; 8-Ag electrode layer. DETAILED DESCRIPTION

[0058] The technical solutions of the present application will be further illustrated by specific embodiments. Those skilled in the art should understand that the embodiments are only used to help understand the present application and should not be regarded as specific limitations to the present application.

[0059] Example 1

[0060] The present embodiment provides a perovskite film layer, which comprises a perovskite phase and an inorganic phase surrounding the perovskite phase.

[0061] At the interface between the perovskite phase and the inorganic phase, the edge profile of the perovskite phase is in a continuous convex shape; the continuous convex shape is a periodic corrugation in the positive projection direction of the z-axis, and the shape of the corrugation is a sinusoidal curve; selecting any continuous corrugation segment of the edge profile of the perovskite phase, the average wavelength of the corrugation in the corrugation segment is 150 μm, the average wave height is 200 μm, and the average ratio of the wave height to the wavelength is 0.8; the distance between the wave peak of the corrugation and the edge of the inorganic phase is > 400 μm.

[0062] The inorganic phase comprises PbI2 and CsBr; the thickness of the inorganic phase is 300 nm; the chemical general formula of the perovskite phase is Cs 0.08 MA 0.22 FA 0.73 Pb(I 0.8 Br 0.2 )3; the thickness of the perovskite phase is 500 nm.

[0063] The embodiment also provides a preparation method of the perovskite film layer, and the preparation method comprises the following steps:

[0064] (1) providing a substrate; the substrate comprises a crystalline silicon bottom cell with a pyramid texture and an ITO intermediate tunnel layer stacked on the pyramid texture.

[0065] (2) depositing an inorganic phase film layer containing PbI2 and CsBr and having a thickness of 300 nm on the ITO intermediate tunnel layer by using a thermal evaporation method.

[0066] (3) depositing an organic phase film layer containing FAI, MABr and MAI on the inorganic phase film layer by using an inkjet printing method; the deposition area of the organic phase film layer is smaller than the area of the inorganic phase film layer; the main parameters of the inkjet printing method comprise: the viscosity of ink droplets is 2 cp, the printing speed of ink droplets is 300 m / s, and the ejection frequency is 1000 Hz.

[0067] (4) performing annealing treatment, so that the organic phase and the inorganic phase react to form a perovskite phase with a chemical formula of Cs 0.08 MA 0.22 FA 0.73 Pb(I 0.8 Br 0.2 )3, and a continuous convex boundary structure is formed at the interface between the perovskite phase and the inorganic phase; wherein the temperature of the annealing treatment is 80℃, and the annealing treatment time is 30 min.

[0068] The embodiment also provides a perovskite-crystalline silicon stacked cell, and a structure diagram thereof is shown in Figure 1 The perovskite-crystalline silicon stacked cell comprises a perovskite cell, an ITO intermediate tunnel layer 2 and a silicon-based cell stacked from top to bottom; wherein the silicon-based cell is a full-texture heterojunction crystalline silicon cell 1; the effective area of the perovskite cell is 1 cm 2 , and along the direction away from the ITO intermediate tunnel layer 2, the perovskite cell comprises a stacked nickel oxide layer 3, a perovskite film layer 4 as described above, a C 60 layer 5, a SnO2 layer 6, an IZO layer 7 and an Ag electrode layer 8; the area of the C 60 layer 5 is equal to the area of the perovskite phase in the perovskite film layer 4.

[0069] Embodiment 2

[0070] The embodiment provides a perovskite film layer, which comprises a perovskite phase and an inorganic phase surrounding the perovskite phase.

[0071] The interface between the perovskite phase and the inorganic phase is a continuous convex edge profile of the perovskite phase; the continuous convex edge profile is a periodic corrugation in the direction of the z-axis projection, and the shape of the corrugation is a sinusoidal curve; the average wavelength of the corrugation in any continuous corrugation segment of the edge profile of the perovskite phase is 100 μm, the average wave height is 150 μm, and the average ratio of the wave height to the wavelength is 1; the distance between the wave peak of the corrugation and the edge of the inorganic phase is > 400 μm.

[0072] The inorganic phase includes PbI2 and CsBr; the thickness of the inorganic phase is 500 nm; the chemical formula of the perovskite phase is Cs 0.08 MA 0.22 FA 0.73 Pb(I 0.8 Br 0.2 )3; the thickness of the perovskite phase is 700 nm.

[0073] The embodiment also provides a preparation method of the perovskite film layer, and the preparation method comprises the following steps:

[0074] (1) providing a substrate; the substrate comprises a crystalline silicon bottom cell with a pyramid surface and an ITO intermediate tunnel layer stacked on the pyramid surface.

[0075] (2) depositing an inorganic phase film layer containing PbI2 and CsBr and having a thickness of 500 nm on the ITO intermediate tunnel layer by a thermal evaporation method.

[0076] (3) depositing an organic phase film layer containing FAI, MABr and MAI on the inorganic phase film layer by an inkjet printing method; the deposition area of the organic phase film layer is smaller than the area of the inorganic phase film layer; the main parameters of the inkjet printing method include: the viscosity of the ink droplet is 2 cp, the printing speed of the ink droplet is 300 m / s, and the ejection frequency is 1000 Hz.

[0077] (4) performing annealing treatment to make the organic phase and the inorganic phase react to form a perovskite phase with a chemical formula of Cs 0.08 MA 0.22 FA 0.73 Pb(I 0.8 Br 0.2 )3, and a boundary structure with a continuous convex shape is formed at the interface between the perovskite phase and the inorganic phase; wherein the temperature of the annealing treatment is 80℃, and the time of the annealing treatment is 30 min.

[0078] The embodiment also provides a perovskite-crystalline silicon stacked cell, which comprises a perovskite cell, an ITO intermediate tunneling layer and a silicon-based cell stacked from top to bottom; wherein the silicon-based cell is a full-textured heterojunction crystalline silicon cell; the effective area of the perovskite cell is 1cm 2 In a direction away from the ITO intermediate tunneling layer, the perovskite cell comprises a nickel oxide layer, a perovskite film layer as described above, a C 60 layer, a SnO2 layer, an IZO layer and an Ag electrode layer stacked in sequence; the area of the C 60 layer is equal to that of the perovskite phase in the perovskite film layer.

[0079] Embodiment 3

[0080] The embodiment provides a perovskite film layer, which comprises a perovskite phase and an inorganic phase surrounding the perovskite phase.

[0081] In the interface between the perovskite phase and the inorganic phase, the edge profile of the perovskite phase is in a continuous convex shape; the continuous convex shape is a periodic wave in the direction of the z-axis projection, and the shape of the wave is a sinusoidal curve; selecting any continuous wave segment in the edge profile of the perovskite phase, the average wavelength of the wave in the wave segment is 200μm, the average wave height is 250μm, and the average ratio of the wave height to the wavelength is 1.2; the distance between the wave peak of the wave and the edge of the inorganic phase is >400μm.

[0082] The inorganic phase comprises PbI2 and CsBr; the thickness of the inorganic phase is 800nm; the chemical general formula of the perovskite phase is Cs 0.08 MA 0.22 FA 0.73 Pb(I 0.8 Br 0.2 )3; the thickness of the perovskite phase is 1000nm.

[0083] The embodiment also provides a preparation method of the perovskite film layer, which comprises the following steps:

[0084] (1) providing a substrate; the substrate comprises a crystalline silicon bottom cell with a pyramid texture and an ITO intermediate tunneling layer stacked on the pyramid texture.

[0085] (2) using a thermal evaporation method to deposit an inorganic phase film layer containing PbI2 and CsBr and having a thickness of 800nm on the ITO intermediate tunneling layer.

[0086] (3) using inkjet printing to deposit an organic phase film layer containing FAI, MABr and MAI on the inorganic phase film layer; the deposition area of the organic phase film layer is smaller than the area of the inorganic phase film layer; the main parameters of the inkjet printing include: the viscosity of the ink droplet is 2 cp, the printing speed of the ink droplet is 300 m / s, and the ejection frequency is 1000 Hz.

[0087] (4) performing annealing treatment to make the organic phase and the inorganic phase react to form a perovskite phase of Cs 0.08 MA 0.22 FA 0.73 Pb(I 0.8 Br 0.2 )3, and a continuous convex boundary structure is formed at the interface between the perovskite phase and the inorganic phase; wherein the temperature of the annealing treatment is 80°C, and the time of the annealing treatment is 30 min.

[0088] The embodiment also provides a perovskite-crystalline silicon stacked cell, which comprises a perovskite cell, an ITO intermediate tunneling layer and a silicon-based cell stacked from top to bottom; wherein the silicon-based cell is a full-textured heterojunction crystalline silicon cell; the effective area of the perovskite cell is 1 cm 2 , and along the direction away from the ITO intermediate tunneling layer, the perovskite cell comprises a nickel oxide layer, a perovskite film layer as described above, a C 60 layer, a SnO2 layer, an IZO layer and an Ag electrode layer which are stacked; the area of the C 60 layer is equal to that of the perovskite phase in the perovskite film layer.

[0089] Example 4

[0090] The difference between the embodiment and example 1 is that the specific parameters of the inkjet printing in step (3) are adjusted so that the average wavelength of the corrugations in the corrugated section is 80 μm.

[0091] The rest of the preparation method and parameters remain the same as those in example 1.

[0092] Example 5

[0093] The difference between the embodiment and example 1 is that the specific parameters of the inkjet printing in step (3) are adjusted so that the average wavelength of the corrugations in the corrugated section is 220 μm.

[0094] The rest of the preparation method and parameters remain the same as those in example 1.

[0095] Example 6

[0096] The difference between this example and Example 1 is that the specific parameters of the inkjet printing method in step (3) are adjusted so that the average wave height of the corrugations in the corrugated section is 100 μm.

[0097] The rest of the preparation method and parameters remain the same as in Example 1.

[0098] Example 7

[0099] The difference between this example and Example 1 is that the specific parameters of the inkjet printing method in step (3) are adjusted so that the average wave height of the corrugations in the corrugated section is 300 μm.

[0100] The rest of the preparation method and parameters remain the same as in Example 1.

[0101] Example 8

[0102] The difference between this example and Example 1 is that the specific parameters of the inkjet printing method in step (3) are adjusted so that the average ratio of the wave height to the wavelength of the corrugations is 0.2.

[0103] The rest of the preparation method and parameters remain the same as in Example 1.

[0104] Example 9

[0105] The difference between this example and Example 1 is that the specific parameters of the inkjet printing method in step (3) are adjusted so that the average ratio of the wave height to the wavelength of the corrugations is 2.

[0106] The rest of the preparation method and parameters remain the same as in Example 1.

[0107] Example 10

[0108] The difference between this example and Example 1 is that the specific parameters of the inkjet printing method in step (3) are adjusted so that the distance between the wave crests of the corrugations and the edge of the inorganic phase is less than 400 μm.

[0109] The rest of the preparation method and parameters remain the same as in Example 1.

[0110] Comparative Example 1

[0111] The difference between this example and Example 1 is that the inkjet printing method in step (3) is replaced by a solution spin coating method.

[0112] The rest of the preparation method and parameters remain the same as in Example 1.

[0113] Figure 2 The edge portion of the stacked battery provided by Example 1 is shown in the actual photographs, respectively, and it can be seen that the edge of the battery prepared by inkjet printing is in the form of continuous protrusions, and presents periodic or quasi-periodic corrugations in the two-dimensional plane.

[0114] Figure 3 A schematic diagram of one side microscopic edge of the perovskite film provided in Example 1 is shown. Figure 4 for Figure 3 Enlarged diagram of the elliptical region. Figure 7 A schematic diagram of the microscopic edges of the perovskite film provided in Comparative Example 1 is shown. Figure 8 for Figure 7 A magnified schematic diagram of the elliptical region shows that, compared to the spin-coated sample, the battery prepared by inkjet printing has a clear boundary between the inorganic phase and the perovskite phase. The spin-coated sample has dendritic regions that are detrimental to battery performance, and all of them are perovskite phases.

[0115] Figure 5 A schematic diagram of the other side microscopic edge of the perovskite film provided in Example 1 is shown. Figure 6 for Figure 5 Enlarged diagram of the elliptical region. Figure 9 A schematic diagram of the other side of the microscopic edge of the perovskite film provided in Comparative Example 1 is shown. Figure 10 for Figure 9 A magnified schematic diagram of the elliptical region shows that, compared to the spin-coated sample, the battery prepared by inkjet printing has a clear boundary between the inorganic phase and the perovskite phase, while the spin-coated sample has no clear boundary and the battery edge is perovskite phase.

[0116] Comparative Example 2

[0117] The difference between this comparative example and Example 1 is that the specific parameters of the inkjet printing method in step (3) are adjusted so that the deposition area of ​​the organic phase film layer is equal to the area of ​​the inorganic phase film layer.

[0118] The remaining preparation methods and parameters are consistent with those in Example 1.

[0119] Performance parameters

[0120] Under the same effective area, the photoelectric performance and stability of the perovskite-crystalline silicon tandem cells provided in the above embodiments and comparative examples were tested.

[0121] The photoelectric performance testing conditions included: current-voltage characteristics and MPP tracking of all devices were measured using a Keithley 2400 source meter in a nitrogen-filled glove box at 25°C under one sun and AM1.5G illumination. Series cells were tested using a solar simulator (Wavelabs) with LED lights. The solar simulator's light intensity was calibrated using a KG5 filtered silicon reference cell calibrated by NREL. (The last sentence appears to be incomplete and possibly refers to a measurement within 1 cm.) 2The J-V curves of the tandem solar cells were drawn from forward (2 V) to reverse (-0.1 V) bias with 0.013 V step and 10 ms dwell time within the active area of the MASK without any pre-bias or light soaking. The maximum power point tracking was performed every 5 seconds using the measurement software.

[0122] The test conditions for stability include: to achieve maximum power point (MPP) tracking, the encapsulated devices were tested in ambient air under continuous illumination of a xenon lamp-based solar simulator (Enli Tech, SS-F5-3A) calibrated to 100 mW·cm -2 of light intensity, with the illumination area blocked by a 1 cm 2 MASK.

[0123] For damp heat testing (85% RH / 85°C), the sealed devices were aged on a hot plate at 85°C with the ambient humidity controlled at 85% RH using a tunable setting ultrasonic humidifier. During J-V measurements, the tandem cells were transferred to a separate room kept at <30% RH and room temperature, and returned to the aging environment immediately after testing.

[0124] The test results are shown in Table 1.

[0125] Table 1

[0126] Voc (V) Jsc(mA / cm 2 )]]> FF (%) PCE (%) Example 1 1.94 19.28 81.42 30.56 Example 2 1.93 19.27 81.22 30.82 Example 3 1.95 19.32 80.44 30.45 Example 4 1.91 18.48 78.36 28.83 Example 5 1.90 18.89 79.66 28.81 Example 6 1.88 18.87 78.45 28.94 Example 7 1.92 18.59 79.28 28.98 Example 8 1.89 18.92 79.37 28.47 Example 9 1.91 18.88 78.94 28.88 Example 10 1.92 18.69 79.95 28.69 Comparative Example 1 1.82 18.72 68.53 24.05 Comparative Example 2 1.87 18.52 79.82 27.96

[0127] Analysis:

[0128] The present application designs a perovskite film layer with a special edge structure, which utilizes the continuous convex perovskite phase formed at the interface between the perovskite phase and the inorganic phase to affect the growth mechanism of the edge perovskite grains, promote their growth in a specific direction, and reduce the grain boundary defects in the film layer. At the same time, the continuous convex shape plays an anchoring role at the edge, which can enhance the interface bonding, promote the separation and transport of photo-generated carriers, reduce the charge recombination rate, and can be used as a buffer layer to reduce the edge leakage phenomenon. In addition, the continuous convex perovskite phase at the interface can relieve the internal stress generated during the nucleation and crystallization process of the perovskite phase, prevent cracks from occurring, thereby improving the photoelectric performance and stability of the battery device.

[0129] As can be seen from the comparison of Example 1 and Examples 4-5, if the average wavelength of the corrugation is too small, it is not conducive to the edge anchoring of the organic phase; if the average wavelength of the corrugation is too large, defects are easily produced, and non-radiative recombination increases.

[0130] As can be seen from the comparison of Example 1 and Examples 6-7, if the average wave height of the corrugation is too small, it is not conducive to the edge carrier buffering, and increases the edge leakage; if the average wave height of the corrugation is too large, it is not conducive to the release of internal stress formed during the crystallization process.

[0131] From the comparison between Example 1 and Examples 8-9, it can be seen that if the average ratio of the wave height and the wave length of the corrugation is too small, it is not conducive to light trapping of the device and increases the reflection; if the average ratio of the wave height and the wave length of the corrugation is too large, it is not conducive to carrier separation and transmission.

[0132] From the comparison between Example 1 and Example 10, it can be seen that if the distance between the wave peak of the corrugation and the edge of the inorganic phase is less than 400 μm, it is not conducive to the growth of the perovskite along a specific direction.

[0133] From the comparison between Example 1 and Comparative Example 1, it can be seen that if the inkjet printing method in step (3) is replaced by the solution spin coating method, the perovskite nucleation is uneven, resulting in a sharp decrease in the electrical performance of the device.

[0134] From the comparison between Example 1 and Comparative Example 2, it can be seen that if the deposition area of the organic phase film layer is equal to the area of the inorganic phase film layer, the solution spreading results in around plating, which reduces the electrical performance of the device.

[0135] It should be noted that the process method of the present application is illustrated by the above examples, but the present application is not limited to the above process steps, that is, it does not mean that the present application must rely on the above process steps to be implemented. Those skilled in the art should understand that any improvement on the present application, equivalent replacement of the materials selected by the present application, addition of auxiliary ingredients, selection of specific methods, etc. fall within the scope of protection and disclosure of the present application.

Claims

1. A perovskite film layer, characterized in that, The perovskite film layer comprises a perovskite phase and an inorganic phase surrounding the perovskite phase; At the interface between the perovskite phase and the inorganic phase, the edge profile of the perovskite phase is in a continuous convex shape.

2. The perovskite film layer of claim 1, wherein, The continuous convex shape is periodic or quasi-periodic corrugation in the direction of the z-axis projection. Preferably, the shape of the corrugation is sinusoidal or arc-like.

3. The perovskite film layer of claim 2, wherein, The wavelength of the corrugation is 50-200 μm. 4.The perovskite film layer of claim 2, wherein, The average wavelength of the corrugation in any continuous corrugation segment of the edge profile of the perovskite phase is 100-200 μm.

5. The perovskite film layer according to any one of claims 2-4, characterized in that, The average wave height of the corrugation in any continuous corrugation segment of the edge profile of the perovskite phase is 150-250 μm. Preferably, the average ratio of the wave height to the wavelength of the corrugation is 0.75-1.

5. Preferably, the distance between the wave peak of the corrugation and the edge of the battery is ≥400 μm.

6. The perovskite film layer according to any one of claims 1-5, wherein The chemical formula of the inorganic phase is BX2, wherein B comprises any one or a combination of at least two of cesium ions, lead ions or tin ions, and X is a halide anion. Preferably, the thickness of the inorganic phase is 300-800 nm. Preferably, the chemical formula of the perovskite phase is AB'X'3, wherein A is an organic cation, B' comprises lead ions and / or tin ions, and X' is a halide anion. Preferably, the thickness of the perovskite phase is 500-1200 nm.

7. A method of producing a perovskite film layer as claimed in any one of claims 1-6, characterized in that, The preparation method comprises the following steps: providing a substrate; depositing an inorganic phase film layer on the substrate; depositing an organic phase film layer on the inorganic phase film layer by inkjet printing, wherein the deposition area of the organic phase film layer is smaller than the area of the inorganic phase film layer; performing post-processing to make the organic phase and the inorganic phase react to form a perovskite phase, and a boundary structure with a continuous convex shape is formed at the interface between the perovskite phase and the inorganic phase.

8. The preparation method according to claim 7, characterized in that, The deposition method of the inorganic phase film layer comprises a dry method, and the dry method comprises thermal evaporation. Preferably, the main parameters of the inkjet printing method comprise: the viscosity of the ink droplet is 2-10 cp, the printing speed of the ink droplet is 100-1000 mm / s, and the ejection frequency of the ink droplet is 100-1000 Hz.

9. The production method according to claim 7 or 8, characterized by, The post-processing is annealing treatment. Preferably, the temperature of the annealing treatment is 50-150 ℃. Preferably, the time of the annealing treatment is 5-30 min.

10. A perovskite-silicon based tandem cell, characterized in that, The perovskite-silicon-based stacked battery comprises a perovskite battery and a silicon-based battery stacked from top to bottom, and the perovskite battery comprises the perovskite film layer according to any one of claims 1-6.

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