Preparation method of perovskite layer and perovskite solar cell

Abstract

The invention relates to a preparation method of a perovskite layer and application of the perovskite layer in a perovskite solar cell. The method comprises the following steps: (1) providing a layer of perovskite film; (2) setting a certain inclination angle between the perovskite thin film and a horizontal processing table; and (3) in the inclined state, scanning on the surface of the thin film along a curve path by using a laser beam, and processing to form a plurality of periodically distributed waveform grooves, thereby obtaining a perovskite layer with a surface microstructure. Wherein the curve path comprises a plurality of waveform curves. By using the method provided by the invention, the prepared perovskite layer with the surface groove microstructure has excellent light capture capability and interface regulation and control performance, the photoelectric conversion efficiency and the environmental stability of the perovskite solar cell are remarkably improved, and the process is suitable for large-scale production.

Description

Technical Field

[0001] The present invention relates to the technical field of perovskite solar cells, and in particular to a method for preparing a perovskite layer and a perovskite solar cell. Background Art

[0002] With the growing global demand for renewable energy, solar cells have garnered widespread attention as a clean energy technology. Since their initial report in 2009, the efficiency of perovskite solar cells has increased from a few percentage points to over 27%. However, perovskite solar cells still face several challenges in their commercialization, particularly in thin-film fabrication. Current methods often rely on complex post-processing steps, lengthy annealing processes, or expensive vacuum equipment, resulting in cumbersome and costly processes that limit their feasibility for large-scale production. Therefore, developing new perovskite thin-film fabrication technologies that are simple, controllable, and suitable for large-scale fabrication has become a key research focus.

[0003] Currently, researchers are using methods such as organic iodide post-treatment, contactless crystallization annealing, low-temperature post-treatment, and ultrasonic vibration to control the crystallization behavior or surface morphology of perovskite films to achieve the construction of high-quality perovskite films and improve device performance. The above strategies mainly rely on the precise design of functional molecules, but the preparation of high-quality, large-area perovskite films still suffers from problems such as poor reproducibility and narrow process windows. Therefore, exploring physical control methods that combine high controllability, low energy consumption, and high adaptability has become a key path to solving the problem of large-scale preparation.

[0004] In order to meet the needs of controllable automation and large-scale production, laser technology has gradually become a potential tool for perovskite film regulation due to its advantages such as strong spatial selectivity, high processing precision, and contactless processing. In ACS Energy Letters 2023, 8(6), 2603-2610, Saliba et al. introduced the concept of physical polishing and used nanosecond pulsed ultraviolet laser to perform surface treatment on perovskite films, effectively reducing surface dangling bonds, eliminating non-perovskite phases, and optimizing the stoichiometric ratio, thereby improving the photoelectric conversion efficiency and stability of the device. CN113089077B reported that femtosecond laser pulses induced solvent volatilization, combined with laser scanning speed adjustment, achieved fine needle-shaped directional crystallization of perovskite in the precursor, reflecting the application potential of laser in crystallization process control.

[0005] Researchers have also attempted to optimize the surface chemical properties of perovskite films through chemical manipulation methods such as organic small molecule passivation, but these methods still have significant shortcomings in terms of uniformity, stability, and cost control over large areas. In contrast, laser technology offers the advantages of adjustable physical parameters, high-speed processing, and high precision, providing a new solution for constructing high-quality thin films.

[0006] Despite the numerous advantages of lasers in materials processing, their application to perovskite thin films still faces the following challenges: First, the matching mechanism between laser parameters and perovskite materials is still unclear, lacking systematic geometric or thermodynamic models to explain the control of laser-induced morphology. Second, the local high energy characteristics of lasers can damage ionic perovskite materials, degrading device performance. Third, there is currently a lack of process window design strategies for constructing controllable microstructures during laser rapid thermal processing. Therefore, developing laser control methods with low damage, controllable structure, and scalable process is an important research direction in the field of perovskite photovoltaics.

[0007] In summary, in the process of perovskite film preparation, how to construct a microstructured film with excellent morphology control ability based on laser processing strategy, and then improve the photoelectric conversion efficiency and operation stability of perovskite solar cells, is a key technical problem that needs to be solved urgently. Summary of the Invention

[0008] In response to the above problems, the present invention provides a method for preparing a perovskite layer and a perovskite solar cell.

[0009] In a first aspect, the present application provides a method for preparing a perovskite layer, characterized in that it comprises the following steps:

[0010] (1) providing a perovskite film;

[0011] (2) placing the perovskite film on a processing table so that a certain inclination angle is formed between the vertical line of the film surface and the incident direction of the laser beam;

[0012] (3) Using a laser beam to scan the surface of the perovskite film in a curved path to form a plurality of spaced-apart wavy grooves to obtain a perovskite layer with a surface microstructure; the curved path includes a plurality of wavy curves.

[0013] In one embodiment, the angle between the laser beam and the perpendicular to the surface of the perovskite film is 10 to 40°, preferably 15 to 30°;

[0014] The depth of the corrugated groove is 40-60 nm and the width is 2-7 nm; and / or

[0015] The total area of ​​the corrugated grooves on the perovskite layer accounts for 20% to 40% of the total area of ​​the perovskite layer.

[0016] In one embodiment, the multiple waveform curves are sine curves and / or cosine curves, the angle between the center lines of each of the multiple waveform curves is 0 to 5°, and the center lines of the multiple waveform curves are approximately perpendicular to one side of the perovskite film.

[0017] In one embodiment, the distance between two adjacent wavy curves is 0.005-0.03 mm.

[0018] In one embodiment, the perovskite film is prepared as follows:

[0019] A perovskite wet film is formed on a substrate, and then the obtained perovskite wet film is subjected to laser annealing and air hot plate annealing to obtain the perovskite thin film.

[0020] In a second aspect, the present application relates to a perovskite solar cell, characterized in that it includes a perovskite layer prepared by the preparation method according to the first aspect of the present application.

[0021] In one embodiment, the perovskite solar cell further includes a conductive substrate, an electron transport layer, a hole transport layer and a cathode, and the perovskite layer is disposed between the electron transport layer and the hole transport layer.

[0022] In one embodiment, the perovskite layer is disposed on an electron transport layer or a hole transport layer.

[0023] In one embodiment, the perovskite solar cell is an upright perovskite solar cell, comprising a conductive substrate, an electron transport layer, a hole transport layer and an electrode layer, wherein the perovskite layer is disposed on the electron transport layer;

[0024] The conductive substrate is ITO and / or FTO;

[0025] The thickness of the electron transport layer is 15 to 25 nm;

[0026] The thickness of the perovskite layer is 300 to 700 nm;

[0027] The thickness of the hole transport layer is 50 to 200 nm;

[0028] The electrode layer has a thickness of 60 to 150 nm.

[0029] In one embodiment, the perovskite solar cell is an inverted perovskite solar cell, comprising a conductive substrate, a hole transport layer, an electron transport layer and an electrode layer, wherein the perovskite layer is disposed on the electron transport layer;

[0030] The conductive substrate is ITO and / or FTO;

[0031] The thickness of the hole transport layer is 20 to 40 nm;

[0032] The thickness of the perovskite layer is 300 to 700 nm;

[0033] The thickness of the electron transport layer is 20 to 40 nm;

[0034] The electrode layer has a thickness of 60 to 150 nm.

[0035] Beneficial effects:

[0036] (1) Improving the overall performance of perovskite devices

[0037] (1) Realize the controllable construction of nanoscale microstructures on the surface of perovskite films

[0038] This application designs a specific waveform path along which a laser beam acts on the surface of a perovskite film, precisely machining the surface to form a periodically distributed micro-groove structure. This microstructure effectively enhances the scattering and absorption of incident light, increasing the short-circuit current density of perovskite solar cells (especially semi-transparent ones), thereby improving the film quality and optoelectronic performance of the perovskite layer.

[0039] (2) Reduce dangling bond defects on the surface of perovskite films

[0040] With the help of the thermal effect induced by the waveform laser path, local heat treatment of the surface of the perovskite film can significantly reduce the concentration of surface dangling bonds, repair surface defect states, and make the interface contact between the perovskite layer and the hole transport layer closer, thereby improving the carrier transport efficiency and interface stability, and enhancing the photoelectric conversion efficiency and environmental stability of the device.

[0041] (3) Increase the interface contact area between the perovskite layer and the upper charge transport layer

[0042] By adopting a non-vertical laser scanning strategy with controllable incident angle and combining it with a waveform path design, the contact area between the perovskite layer and its upper charge transfer layer is effectively increased, the energy level matching and interface bonding characteristics are optimized, and the charge extraction efficiency and overall device performance are further improved.

[0043] (2) Enhance the value of industrial applications

[0044] (1) Compatible with mainstream laser processing equipment, facilitating production line integration

[0045] This method can utilize the 1064nm or 532nm laser equipment widely used on existing production lines, without the need to introduce dedicated or expensive new equipment, to achieve high-precision structural control of perovskite films, which will help promote the continuous and low-cost manufacturing of perovskite solar cells.

[0046] (2) Break through the dependence on closed environment and realize large-scale preparation under open production line conditions

[0047] This method avoids dependence on inert atmosphere environments such as glove boxes, and can directly prepare high-quality perovskite layers in an open production line environment. It has good process scalability and is suitable for large-scale manufacturing of large-area modular perovskite solar cells. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1A and Figure 1B Schematic diagrams of one embodiment of a perovskite solar cell with an upright structure and an inverted structure respectively;

[0049] Figure 2 Schematic diagram of one embodiment of the preparation process of the perovskite layer of the present invention;

[0050] Figure 3 A schematic diagram of a waveform drawing having a waveform curve drawn thereon;

[0051] Figure 4 Schematic diagram of a drawing with a waveform curve used in Example 1 of the present invention, wherein the right figure shows the expression of a sine curve;

[0052] Figure 5A and Figure 5B Schematic diagrams of the laser drawings used in Example 4 and Example 5, respectively;

[0053] Figure 6A This is a scanning electron microscope photograph of the surface of the perovskite layer prepared in Example 1 of the present invention. Figure 6B for Figure 6A A partial enlarged view of

[0054] Figure 7A This is a scanning electron microscope photograph of the surface of the perovskite layer prepared in Comparative Example 2. Figure 7B for Figure 7A A partial enlarged view of

[0055] Figure 8A and Figure 8B Schematic diagrams of the laser drawings used in Comparative Examples 3 and 4, respectively.

[0056] Figure 9A 、 Figure 9B ,as well as Figure 9C Schematic diagrams of the tilt angles of the perovskite film and the horizontal processing platform in Example 1, Example 7, and Example 8, respectively. DETAILED DESCRIPTION

[0057] The present application will be further described in detail below through the accompanying drawings and examples, through which the features and advantages of the present application will become more clear and distinct.

[0058] The word "exemplary" is used exclusively herein to mean "serving as an example, example, or illustration." Any embodiment described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments. Although various aspects of the embodiments are shown in the drawings, the drawings are not necessarily drawn to scale unless otherwise indicated.

[0059] In addition, the technical features involved in different embodiments of the present application described below can be combined with each other as long as they do not conflict with each other.

[0060] In one aspect, the present invention provides a method for preparing a perovskite layer, comprising the following steps:

[0061] (1) providing a perovskite film;

[0062] (2) placing the perovskite film on a processing table so that a certain inclination angle is formed between the vertical line of the film surface and the incident direction of the laser beam;

[0063] (3) using a laser beam to scan the surface of the perovskite film in a curved path to form a plurality of periodically distributed wavy grooves to obtain a perovskite layer with a surface microstructure;

[0064] Wherein, the curved path includes a plurality of waveform curves.

[0065] It should be noted that Figure 3 A diagram showing a curved path includes multiple wavy curves spaced apart from each other along the direction a and forming a periodic pattern. When a laser beam is scanned along the curved path over the surface of the perovskite film, multiple periodically distributed wavy grooves are formed on the surface. These periodically distributed wavy grooves are similar in form to the curved path, being periodically distributed and spaced apart from each other along the direction a.

[0066] It should be noted that the inventors of this application have deeply explored the effect of laser heat on the surface structure of the perovskite film, and made the laser beam hit the surface of the perovskite film along the path of the waveform curve. Figure 3 The laser beam hits the surface of the perovskite film and travels along the path of the waveform curve in the perovskite film, and the angle between the laser beam and the vertical line of the perovskite film surface is controlled so that it is not perpendicular to the perovskite film surface. Figure 3As shown, from top to bottom, the laser beam travels along a wavy curve and then along the next wavy curve, controlling the surface morphology of the perovskite film so that a plurality of wavy grooves are formed on the surface of the perovskite film at intervals, thereby forming a microstructure of micro grooves. This microstructure can effectively improve the incidence of light, improve the short-circuit current density of the semi-transparent solar cell, and thus improve the preparation efficiency and quality of the perovskite light-absorbing layer. In addition, the thermal effect of the laser along the wavy curve path acts on the surface of the perovskite film, which can eliminate some dangling bonds on the surface of the perovskite film, increase the contact area with the upper charge transport layer (hole transport layer or electron transport layer), enable it to better contact with the upper charge transport layer, improve the carrier transport capacity, and lay a solid foundation for the performance and stability of the solar cell. This technology is not only expected to achieve large-scale, automated production, but also to create a new method for high-throughput and rapid preparation of large-area, high-quality perovskite films. In one embodiment, the angle between the laser beam and the perpendicular to the surface of the perovskite film is 10 to 40 degrees, preferably 15 to 30 degrees, for example 20 degrees, 25 degrees, 35 degrees, etc. The direction of the laser beam is typically perpendicular to the horizontal processing table. Therefore, by adjusting the angle between the perovskite film and the horizontal processing table, the perovskite film can be slightly tilted, thereby controlling the angle between the laser beam and the perpendicular to the surface of the perovskite film to be 10 to 40°, preferably 15 to 30°. Alternatively, the direction of the laser beam can be adjusted so that it is not perpendicular to the horizontal processing table, thereby also controlling the angle between the laser beam and the perpendicular to the surface of the perovskite film to be 10 to 40°, preferably 15 to 30°.

[0067] In one embodiment, the curved path includes a plurality of wavy curves, wherein the plurality of wavy curves are sine curves and / or cosine curves, wherein the angle between the center lines of the plurality of wavy curves is 0 to 5°, and the center lines of the plurality of wavy curves are approximately perpendicular to one side of the perovskite film. The center lines of the plurality of wavy curves are approximately parallel, and are all approximately perpendicular to one side of the perovskite film. “Approximately parallel” means that the angle between the center lines of the plurality of wavy curves is 0 to 5°, and “approximately perpendicular” means that the angle (acute angle) between the center line and one side of the perovskite film is 85 to 90°. In one embodiment of the aforementioned preparation method of the present invention, a drawing with a wavy curve can be imported into a laser device, or the parameters of the laser device can be set, so that the laser beam travels on the surface of the perovskite film according to the path of the set wavy curve. In the process of the laser traveling on the surface of the perovskite film according to the set wavy path curve, a plurality of wavy grooves are formed on the surface of the perovskite film, and the curve form of the wavy grooves is approximately consistent with the wavy curve.

[0068] In another embodiment of the aforementioned preparation method of the present invention, the expression of the sine curve is The expression of the cosine curve is

[0069] Wherein, in the expressions of the sine curve and the cosine curve, A is the amplitude, which represents the maximum distance from the center line, and can be 1 to 10 μm, for example, 5 μm; is the initial phase, which can be 0~2π, indicating the phase when x=0; ω is the angular velocity, reflecting the period of the sine or cosine curve, which is not 0, and can be a number greater than 0 and less than or equal to 5, for example, it can be 0.2~2, such as 0.5~1.

[0070] It should be noted that the inventors of this application studied the impact of thermal effects of different laser modes on the surface morphology of perovskite films. By further exploring the changes in the surface morphology of perovskite films under the laser thermal effect, they controlled parameters such as the laser spot size, power, and action time, as well as the image of the sine and / or cosine curves, as the laser beam traveled across the surface of the perovskite film along a path that satisfied the aforementioned sine and / or cosine curves. This enabled the controllability of the surface structure of the perovskite film at low energy. Ultimately, this improved the photoelectric conversion efficiency and stability of perovskite solar cells, enabling the low-consumption and low-energy preparation of the perovskite phase.

[0071] The width of the corrugated groove can be controlled by controlling the spot size of the laser beam, the depth of the corrugated groove can be controlled by controlling the power and action time of the laser beam, and the area ratio of the corrugated groove (as a percentage of the total area of ​​the perovskite layer) can be controlled in combination with the number of corrugated curves. The inventors of the present application have found that the performance (photoelectric conversion efficiency, etc.) of the final perovskite solar cell prepared by the perovskite layer of the present application is affected by the depth and area ratio of the corrugated groove. In one embodiment, each of the multiple corrugated curve paths has the same corrugated pattern, and each of the multiple corrugated grooves formed thereby also has approximately the same corrugated pattern and has approximately the same width and depth. For example, the depth of each corrugated groove is 40 to 60 nm and the width is 2 to 7 nm. In one embodiment, the total area of ​​the corrugated grooves on the perovskite layer accounts for 20% to 40% of the total area of ​​the perovskite layer.

[0072] In another embodiment of the above-mentioned preparation method of the present invention, the distance between two adjacent waveform curves is 0.005 to 0.03 mm. Figure 3As shown, if the horizontal direction is used as the x-axis and the vertical direction is used as the y-axis, the spacing between two adjacent waveform curves represents the distance in the y-axis direction between two points corresponding to the same x-axis coordinate of the two adjacent waveform curves. There is almost no distance between the left or right end of the multiple waveform curves and the side of the perovskite film on the nearer side, and the distance can be less than 0.01mm; there is almost no distance between the top waveform curve and the upper side of the perovskite film, and the distance between the highest point of the top waveform curve and the upper side of the perovskite film can be less than 0.01mm; there is almost no distance between the bottom waveform curve and the lower side of the perovskite film, and the distance between the lowest point of the bottom waveform curve and the lower side of the perovskite film can be less than 0.01mm.

[0073] When the multiple waveforms are sine and / or cosine curves, the angle between the centerlines of each of the multiple waveforms is 0-5°, and the angle is substantially perpendicular to a side of the perovskite film. It should be noted that the perovskite film can generally be rectangular. The number of waveform paths that the laser beam needs to travel on the surface of a perovskite film of a certain size can be determined based on the spacing between two adjacent waveforms and the value of the amplitude A in the expression of the sine or cosine curve.

[0074] It should be noted that in the aforementioned preparation method of the present invention, a laser device can be used to generate the laser. For example, the parameters of the laser device include: a laser frequency of 200kHz, a laser pulse width of 120ns, a laser wavelength of 1064nm; a laser power of 3%, and a focal distance of 5cm. The laser is preferably a near-infrared laser with a wavelength of 1064nm or a green laser with a wavelength of 532nm. This allows the perovskite film to be processed directly using the laser equipment used on the production line and independently designed waveform curve drawings, eliminating the need to purchase equipment and achieving continuous preparation of perovskite solar cells. This overcomes the disadvantage of perovskite solar cells needing to be prepared in a glove box, achieving continuous preparation of high-quality perovskite layers in an ambient environment, and the technology is scalable, enabling the preparation of large-area perovskite solar cells.

[0075] In the above-mentioned preparation method of the present invention, the laser beam is made to hit the surface of the perovskite film in a waveform path, and the parameters of the laser device when emitting the laser are adjusted so that the laser beam forms regular stripes on the surface of the perovskite film, that is, Figure 6A and 6B The surface microstructure of the micro grooves observed in the scanning electron microscope photograph is cleverly controlled by controlling the depth and width of the undulations (grooves) formed on the surface of the perovskite film as described above.

[0076] The inventors of this application have discovered that when the corrugated grooves have a sine or cosine curve, and the total area ratio of the corrugated grooves on the perovskite film and the depth and width of the corrugated grooves are within the above ranges, the final perovskite solar cell prepared from the perovskite layer of this application has better photoelectric performance (photoelectric conversion efficiency, etc.). It is speculated that when a surface texture structure with grooves of the above parameters is formed on the perovskite film, the incidence of light can be effectively improved, the light extraction efficiency can be improved, and the short-circuit current density of the solar cell can be increased; such a surface texture structure is beneficial to the increase of photon scattering on the surface of the film, which can improve wettability, eliminate some dangling bonds on the surface of the perovskite film, and increase the contact area with the upper transmission layer, making the contact between it and the upper transmission layer closer, improving the carrier transmission capacity, and thus improving the photoelectric conversion efficiency and stability of the battery device.

[0077] In one embodiment of the aforementioned preparation method of the present invention, the thickness of the perovskite layer is 300 to 700 nm. It should be noted that in the preparation method of the present invention, controlling the thickness of the perovskite layer as described above can enable the perovskite layer to have excellent performance, thereby obtaining a battery device with excellent performance.

[0078] In another embodiment of the aforementioned preparation method of the present invention, the perovskite film is prepared as follows:

[0079] A perovskite wet film is formed on a substrate, and then the obtained perovskite wet film is subjected to laser annealing and air hot plate annealing to obtain the perovskite thin film.

[0080] It should be noted that after the perovskite film is obtained by air hot plate annealing, it can be cooled and then the aforementioned step (2) is performed to make the laser beam travel on the surface of the perovskite film in a waveform path.

[0081] In another embodiment of the aforementioned preparation method of the present invention, the perovskite layer includes a semiconductor compound with a structural formula of ABX3, wherein A is one or more monovalent organic cations selected from amine, amidine, and cesium, B is one or more divalent metal ions selected from lead, tin, rubidium, silver, bismuth, silicon, and magnesium, and X is one or more selected from iodide, chloride, bromide, thiocyanate, and acetate.

[0082] The method for forming the perovskite wet film can adopt methods known in the art, for example, the perovskite precursor solution can be coated by a combination of one or more processes such as spin coating, doctor blade coating, Czochralski coating, slit coating, and spray coating. In the aforementioned preparation method of the present invention, the perovskite wet film can be first prepared by spin coating, and then laser annealing and air hot plate annealing are performed in sequence to obtain a perovskite film. The perovskite film thus obtained is then subjected to the aforementioned step (2) to allow the laser beam to travel on the surface of the perovskite film in a waveform path, thereby further improving the performance of the perovskite layer, which is conducive to obtaining a battery device with better performance.

[0083] It should be noted that by optimizing the perovskite precursor, the surface of the perovskite film can be controlled to match the laser absorption coefficient, and the local thermal effect generated by the laser can be precisely controlled to affect the morphology of the surface of the perovskite film. Then, a controllable laser technology that makes the surface of the perovskite film undulate with a waveform curve is constructed, which promotes the efficient and rapid preparation of perovskite polycrystalline thin films, i.e., perovskite layers. The prepared perovskite layers have excellent performance, which can improve the photoelectric conversion efficiency and stability of battery devices.

[0084] In one embodiment of the aforementioned preparation method of the present invention, the conditions for performing the laser annealing include: a laser wavelength of 1064 nm or 532 nm, a focal length of 5 to 6 cm, and a time of 20 to 40 s. The temperature of the hot plate during air hot plate annealing can specifically be 90 to 150°C, such as 100°C, 110°C, 120°C, etc., and the time for air hot plate annealing can specifically be 5 to 60 min, such as 10 min, 20 min, 30 min, 40 min, etc. By controlling the conditions of laser annealing and air hot plate annealing as above, it is beneficial to obtain a perovskite film with excellent performance, and then using a laser device to move the laser beam along a wavy curve path on the surface of the perovskite film, a perovskite layer with excellent performance can be obtained to improve the photoelectric conversion efficiency and stability of the battery device.

[0085] On the other hand, the present invention also provides a perovskite solar cell, comprising a perovskite layer prepared by the above preparation method.

[0086] In one embodiment of the aforementioned perovskite solar cell of the present invention, the perovskite solar cell further comprises a conductive substrate, an electron transport layer, a hole transport layer, and a cathode, wherein the perovskite layer is disposed between the electron transport layer and the hole transport layer. It should be noted that the perovskite solar cell of the present invention is not limited to upright devices and inverted devices, and the method can be applied to both upright and inverted devices to improve the performance of the cell. Figure 1A and Figure 1B Schematic diagrams showing an embodiment of a perovskite solar cell with an upright structure and an inverted structure, respectively, Figure 1AIt is an upright structure, which includes, from bottom to top, a conductive substrate 6, an electron transport layer 4, a perovskite layer 1 prepared by the method of the present application, a hole transport layer 2; and an electrode layer 5. Figure 1B It is an inverted structure, which includes, from bottom to top, a conductive substrate, a hole transport layer, a perovskite layer prepared by the method of the present application, an electron transport layer; and an electrode layer.

[0087] In another embodiment of the aforementioned perovskite solar cell of the present invention, the conductive substrate is ITO and / or FTO.

[0088] The thickness of the electron transport layer in the upright device is 15 to 25 nm, and the electron transport layer may include an n-type inorganic or organic semiconductor material, preferably selected from PCBM, ZnTiO3, TiO2, SnO2, ZnO, ZnO-ZnS, and combinations thereof. The thickness of the electron transport layer in the inverted device is 20 to 40 nm, and may include PCBM, BCP, and combinations thereof.

[0089] The thickness of the hole transport layer in the upright device is 50 to 200 nm, and the hole transport layer may comprise a p-type inorganic or organic semiconductor material, preferably selected from NiO x , CuI, CuSCN, spiro-OMeTAD (2,2′,7,7′-tetrakis(N,N-di-p-methoxyphenylamine)9,9′-spirobifluorene), P3HT (poly-3-hexylthiophene), PTAA (poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine]), and combinations thereof. The hole transport layer in the inverted device has a thickness of 20 to 40 nm and may include nickel oxide nanoparticles, SAM molecules, and combinations thereof.

[0090] The thickness of the electrode layer is 60 to 150 nm, and the material of the electrode is one or more selected from gold, silver, carbon, ITO, and AZO.

[0091] It should be noted that the conductive substrate serving as the transparent electrode can be pretreated before the charge transport layer is prepared. The pretreatment may include ultrasonic cleaning with glass cleaner, isopropyl alcohol, and ethanol, followed by drying with a nitrogen stream, and then plasma treatment. The electron transport layer of the upright device can be spin-coated onto a conductive glass substrate from a SnO2 nanoparticle precursor solution, or a layer of SnO2 can be grown using chemical bath deposition (CBD). The hole transport layer of the inverted device can be spin-coated onto a conductive glass substrate from a SAM molecule precursor solution. Using the aforementioned materials for the conductive substrate, the aforementioned electron transport layer and the thickness of the hole transport layer as described above are used, and the aforementioned electrode material and the thickness of the back electrode are used as described above can enable the perovskite solar cell to have high photoelectric conversion efficiency and stability. After 1000 hours of aging, the photoelectric conversion efficiency retention rate of the perovskite solar cell can reach up to 90%.

[0092] The present invention is further described in detail below by way of examples, but the present invention is not limited thereto. In the following examples, unless otherwise specified, the experimental instruments and raw materials involved are all commercially available products.

[0093] Example 1

[0094] This embodiment is based on the controllable waveform laser technology that makes the surface of the perovskite film fluctuate. Figure 1A The upright perovskite solar cell shown includes the following steps:

[0095] Step S1, cleaning the conductive glass substrate: ultrasonically treat the FTO conductive glass substrate with glass cleaning agent, isopropyl alcohol, and ethanol for 15 minutes in sequence. After cleaning, blow dry with nitrogen flow, and then plasma treat for 20 minutes;

[0096] Step S2, including steps S2-1 to S2-2;

[0097] Step S2-1, preparing a SnO2 nanoparticle dispersion: dispersing SnO2 nanoparticles with a size of 5 nm in an isopropyl alcohol solvent, shaking and mixing to obtain a nanoparticle dispersion with a concentration of 10 mg / mL;

[0098] Step S2-2, preparing an electron transport layer: spin-coating a SnO2 nanoparticle dispersion on the conductive glass substrate obtained in step S1 at 4000 rpm for 30 seconds, annealing at 150°C for 30 minutes, to obtain an electron transport layer with a thickness of 20 nm. Post-preparation plasma treatment was performed for 20 minutes.

[0099] Step S3, including steps S3-1 to S3-2;

[0100] Step S3-1, preparing a perovskite precursor solution: dissolving PbI2, FAI, and CsI at a molar ratio of 1:0.95:0.05 in a solvent (a mixture of NMP and DMF in a volume ratio of 1:5), shaking and mixing to obtain a precursor solution with a concentration of 1.3 mol / L;

[0101] Step S3-2, preparation of perovskite layer: spin-coat the perovskite precursor solution on the electron transport layer obtained in step S2, the spin-coating condition is 6000rpm, the spin-coating time is 35s, and there is no anti-solvent treatment. Place the prepared perovskite wet film under the laser equipment, import the laser drawing (parallel horizontal lines with adjacent spacing of 0.01mm, a total of 1998 lines), adjust the focal distance to 2cm, and use a 1064nm near-infrared laser to process the perovskite wet film according to the drawing. The process takes 20s in total. After the end, anneal the perovskite intermediate film on a 110℃ hot plate in an air environment (humidity 40%, temperature 25℃) for 10 minutes, and then cool it naturally. Place the cooled perovskite film under the laser equipment, and use a glass sheet of a certain thickness to pad one side of the perovskite film so that the perovskite film and the horizontal laser processing platform present an angle of about 20° (such as Figure 9A As shown), then draw the waveform chart with the waveform curve (as shown Figure 4 As shown) is imported into the computer that controls the laser equipment, Figure 4 The drawing includes multiple waveform curves with upper and lower intervals. The waveform curves are gentle sine curves. Except for the different positions, the other characteristics of each sine curve on the drawing are the same. The expression of the sine curve is The A value is 5μm, the ω value is 1 / 2, and the sine wave period is 4 chords. is 0; the spacing between the two adjacent sine waves is 0.01mm, the cell size is 20mm*20mm (the size of the perovskite wet film), and there are 1998 sine wave curves on the drawing. Use the software to control the laser to open the imported laser drawing, set the laser power to 3%, the laser frequency to 200kHz, the laser pulse width to 120ns, the focal distance to 5cm, and select a 1064nm near-infrared laser. The laser parameters will automatically drive the laser controller (Laser controller) to emit a laser beam to process the perovskite dry film (the laser beam is vertically irradiated on the horizontal laser processing platform). The laser beam hits the surface of the perovskite film in a waveform path, from top to bottom, and continues to hit the laser beam along the next waveform after hitting the laser beam along one waveform. The surface of the treated perovskite dry film presents nanoscale micro grooves (such as Figure 6A and 6BAs shown), the groove depth is about 50nm and the width is about 5nm, resulting in a perovskite layer with a thickness of 500nm, which effectively improves the incident light and increases the current density of the perovskite solar cell device. The preparation process of the above perovskite layer is as follows Figure 2 shown.

[0102] The total area ratio of the trench can be calculated as follows:

[0103] The path length of each groove can be determined according to the scanning speed and time of the laser, and the width of the groove can be determined according to the size of the light spot.

[0104] The time it takes for the laser to act on a 20mm*20mm perovskite film is about 55s. According to the drawing, there are a total of 1998 sine curves, that is, the time it takes to complete each sine curve is 55 / 1998, which is approximately equal to 0.0275s. The laser scanning speed is 1000mm / s, so the path length of a groove is 1000*0.0275=27.5mm. When the focal distance is 5cm, the diameter of the laser spot is 0.002mm, and the area of ​​each groove can be approximated to the area of ​​a rectangle with a length of 27.5mm and a width of 0.002mm, which is equal to 27.5*0.002=0.055mm. 2 There are 1998 grooves in total, and the total area of ​​the grooves is 0.055*1998=109.89mm 2 The total area of ​​the perovskite layer is 20*20=400mm 2 The percentage of the groove area to the total area of ​​the perovskite layer is 109.89 / 400=27.47%.

[0105] Figure 6A and 6B This is a scanning electron microscope photograph of the surface of the perovskite layer prepared in Example 1 of the present invention, wherein Figure 6B yes Figure 6A A partial enlarged view of the following. Figure 7A and Figure 7B Compared with Figure 6A and 6B Obvious grooves can be seen in it.

[0106] Step S4, including steps S4-1 to S4-2;

[0107] Step S4-1, preparing SpiroOMeTAD hole transport layer material: dissolving 90 mg of SpiroOMeTAD in 1 mL of chlorobenzene solvent, adding 17.5 μL of LiTFSI (lithium bis(trifluoromethanesulfonyl)imide, dissolved in acetonitrile, concentration of 520 mg / mL) and 28.8 μL of tBP (tetra-tert-butylpyridine), and shaking for 1 h to obtain a SpiroOMeTAD solution;

[0108] Step S4-2, preparing a hole transport layer: spin-coating the SpiroOMeTAD solution on the perovskite layer obtained in step S3 at a spin coating condition of 4000 rpm for 30 seconds to obtain a hole transport layer with a thickness of 100 to 200 nm;

[0109] Step S5, preparing the cathode: evaporating metallic silver on the hole transport layer prepared in step S4 to obtain an anode with a film thickness of 100 nm.

[0110] Thus, an upright perovskite solar cell prepared by a waveform laser technology that can control the undulation of the perovskite film surface provided in this embodiment is obtained, which is recorded as P-1.

[0111] Example 2

[0112] This embodiment is based on the waveform laser technology that can control the surface undulation of the perovskite film. Figure 1B The inverted structure perovskite solar cell shown includes the following steps:

[0113] Steps S1 to S2 are the same as steps S1 to S2 in Example 1;

[0114] Step S2, including steps S2-1 to S2-2;

[0115] Step S2-1, preparing a SAM dispersion: dispersing SAM molecules (MeO-2PACZ) in isopropanol solvent and shaking to mix uniformly to obtain a SAM molecular dispersion with a concentration of 0.5 mg / mL;

[0116] Step S2-2, preparing a hole transport layer: spin-coating the SAM molecular dispersion on the conductive glass substrate obtained in step S1 at 3000 rpm for 20 seconds, followed by annealing at 100° C. for 5 minutes to obtain a hole transport layer with a thickness of 30 nm;

[0117] Step S3 is the same as step S3 in Example 1.

[0118] Step S4, including steps S4-1 to S4-2;

[0119] Step S4-1, preparing PCBM and BCP electron transport layer materials: dissolving 10 mg of PCBM in 1 mL of chlorobenzene solvent to prepare a PCBM dispersion with a concentration of 10 mg / mL, and shaking for 1 hour to obtain a PCBM solution; dissolving 10 mg of BCP in 1 mL of isopropanol solvent to prepare a BCP dispersion with a concentration of 10 mg / mL, and shaking for 1 hour to obtain a BCP solution;

[0120] Step S4-2, preparing an electron transport layer: spin-coating a PCBM solution on the perovskite layer obtained in step S3 at a spin coating condition of 5000 rpm for 30 seconds, annealing at 100°C for 10 minutes, and then continuing to spin-coat a BCP solution on the obtained film after cooling at a spin coating condition of 5000 rpm for 30 seconds to obtain an electron transport layer with a thickness of 30 to 40 nm;

[0121] Step S5 is the same as step S5 in Example 1.

[0122] Thus, an inverted perovskite solar cell prepared by a waveform laser technology that can control the undulation of the perovskite film surface provided in this embodiment is obtained, which is recorded as P-2.

[0123] Example 3

[0124] This embodiment is based on the waveform laser technology that can control the surface undulation of the perovskite film. Figure 1A The perovskite solar cell with an upright structure shown includes the following steps:

[0125] Steps S1 to S2 are the same as steps S1 to S2 in Example 1;

[0126] Step S3 is identical to step S3 in Example 1. It is noteworthy that in this embodiment, after hot plate annealing, laser treatment using a wave-shaped path was performed with a laser focus distance of 4 cm. The surface of the treated perovskite dry film exhibited nanoscale microgrooves with a depth of 60 nm. The groove width and area ratio were the same as in Example 1.

[0127] Step S4 is the same as step S4 in Example 1.

[0128] Step S5 is the same as step S5 in Example 1.

[0129] Thus, an upright perovskite solar cell prepared by a waveform laser technology that can control the undulation of the perovskite film surface provided in this embodiment is obtained, which is recorded as P-3.

[0130] Example 4

[0131] This embodiment is based on the waveform laser technology that can control the surface undulation of the perovskite film. Figure 1A The perovskite solar cell with an upright structure shown includes the following steps:

[0132] Steps S1 to S2 are the same as steps S1 to S2 in Example 1;

[0133] Step S3 is identical to step S3 in Example 1. It is noteworthy that in this embodiment, after hot plate annealing, laser treatment using a wave-shaped path was performed with a laser focus distance of 3 cm. The surface of the treated perovskite dry film exhibited nanoscale microgrooves with a depth of 70 nm. The groove width and area ratio were the same as in Example 1.

[0134] Step S4 is the same as step S4 in Example 1.

[0135] Step S5 is the same as step S5 in Example 1.

[0136] Thus, an upright perovskite solar cell prepared by a waveform laser technology that can control the undulation of the perovskite film surface provided in this embodiment is obtained, which is recorded as P-4.

[0137] Example 5

[0138] This embodiment is based on the waveform laser technology that can control the surface undulation of the perovskite film. Figure 1A The perovskite solar cell with an upright structure shown includes the following steps:

[0139] Steps S1 to S2 are the same as steps S1 to S2 in Example 1;

[0140] Step S3 is the same as step S3 in Example 1. It is worth noting that in this embodiment, when the laser treatment is performed in a wave-shaped curve path after the hot plate annealing, the laser is introduced Figure 5A The laser drawing shown has a waveform curve spacing of 0.005 mm. The surface of the treated perovskite dry film shows nanoscale micro grooves with a depth of 50 nm and a width the same as that of Example 1. Figure 5A The number of waveform curves in the laser drawing shown is about twice that of Example 1, for a total of 3998 waveform curves. Each sinusoidal curve on the drawing has the same characteristics except for its position. The expression of the sinusoidal curve is The A value is 2.5μm, the ω value is 1 / 2, and the sine wave period is 4 chords. =0; the spacing between two adjacent sine waves is 0.005mm, and the cell size is 20mm*20mm (the size of the perovskite wet film). Since the laser scanning speed remains unchanged, the time it takes for the laser to act on a 20mm*20mm perovskite film becomes about 110s. The area of ​​each groove can be approximated to the area of ​​a rectangle with a length of 27.5mm and a width of 0.002mm, which is equal to 27.5*0.002=0.055mm 2 There are 3998 grooves in total, and the total area of ​​the grooves is 0.055*3998=219.89mm 2 The total area of ​​the perovskite layer is 20*20=400mm2 The percentage of the groove area to the total area of ​​the perovskite layer is 219.89 / 400=54.97%.

[0141] Step S4 is the same as step S4 in Example 1.

[0142] Step S5 is the same as step S5 in Example 1.

[0143] Thus, an upright perovskite solar cell prepared by a waveform laser technology that can control the undulation of the perovskite film surface provided in this embodiment is obtained, which is recorded as P-5.

[0144] Example 6

[0145] This embodiment is based on the waveform laser technology that can control the surface undulation of the perovskite film. Figure 1A The perovskite solar cell with an upright structure shown includes the following steps:

[0146] Steps S1 to S2 are the same as steps S1 to S2 in Example 1;

[0147] Step S3 is the same as step S3 in Example 1. It is worth noting that in this embodiment, when the laser treatment is performed in a wave-shaped curve path after the hot plate annealing, the laser is introduced Figure 5B The laser drawing shown has a waveform curve spacing of 0.02 mm. The surface of the treated perovskite dry film shows nanoscale micro grooves with a depth of 50 nm and a width the same as that of Example 1. Figure 5B The number of waveform curves in the laser drawing shown is about 1 / 2 of the number in Example 1, for a total of 998 waveform curves. Each sinusoidal curve on the drawing has the same characteristics except for its position. The expression of the sinusoidal curve is The A value is 10μm, the ω value is 1 / 2, and the sine wave period is 4 chords. =0; the spacing between two adjacent sine waves is 0.02mm, and the cell size is 20mm*20mm (the size of the perovskite wet film). Since the laser scanning speed remains unchanged, the time it takes for the laser to act on a 20mm*20mm perovskite film becomes about 30s. The area of ​​each groove can be approximated to the area of ​​a rectangle with a length of 27.5mm and a width of 0.002mm, which is equal to 27.5*0.002=0.055mm 2 There are 998 grooves in total, and the total area of ​​the grooves is 0.055*998=54.89mm 2 The total area of ​​the perovskite layer is 20*20=400mm 2 The percentage of the groove area to the total area of ​​the perovskite layer is 54.89 / 400=13.72%.

[0148] Step S4 is the same as step S4 in Example 1.

[0149] Step S5 is the same as step S5 in Example 1.

[0150] Thus, an upright perovskite solar cell prepared by a waveform laser technology that can control the undulation of the perovskite film surface provided in this embodiment is obtained, which is recorded as P-6.

[0151] Example 7

[0152] This embodiment is based on the waveform laser technology that can control the surface undulation of the perovskite film. Figure 1A The perovskite solar cell with an upright structure shown includes the following steps:

[0153] Steps S1 to S2 are the same as steps S1 to S2 in Example 1;

[0154] Step S3 is the same as step S3 in Example 1. It is worth noting that in this embodiment, the cooled perovskite film is placed under the laser equipment, and a glass sheet of different thickness from that in Example 1 is used to support one side of the perovskite film so that the perovskite film and the horizontal laser processing platform present an angle of about 10° (e.g. Figure 9B shown).

[0155] Step S4 is the same as step S4 in Example 1.

[0156] Step S5 is the same as step S5 in Example 1.

[0157] Thus, an upright perovskite solar cell prepared by a waveform laser technology that can control the undulation of the perovskite film surface provided in this embodiment was obtained, which was recorded as P-7.

[0158] Example 8

[0159] This embodiment is based on the waveform laser technology that can control the surface undulation of the perovskite film. Figure 1A The perovskite solar cell with an upright structure shown includes the following steps:

[0160] Steps S1 to S2 are the same as steps S1 to S2 in Example 1;

[0161] Step S3 is the same as step S3 in Example 1. It is worth noting that in this embodiment, the cooled perovskite film is placed under the laser equipment, and a glass sheet of different thickness from that in Example 1 is used to support one side of the perovskite film so that the perovskite film and the horizontal laser processing platform present an angle of about 40° (e.g. Figure 9C shown).

[0162] Step S4 is the same as step S4 in Example 1.

[0163] Step S5 is the same as step S5 in Example 1.

[0164] Thus, an upright perovskite solar cell prepared by a waveform laser technology that can control the undulation of the perovskite film surface provided in this embodiment is obtained, which is recorded as P-8.

[0165] Comparative Example 1

[0166] This comparative example provides Figure 1A The preparation method of the upright structure perovskite solar cell shown in FIG.

[0167] Steps S1 to S2 are the same as steps S1 to S2 in Example 1;

[0168] Step S3, including steps S3-1 to S3-2;

[0169] Step S3-1 is the same as step S3-1 in Example 1;

[0170] Step S3-2, preparing a perovskite layer: spin-coating a perovskite precursor solution on the electron transport layer obtained in step S2 at 6000 rpm for 35 seconds, adding 150 μL of ethyl acetate antisolvent at the 20th second countdown, annealing on a hot plate at 100° C. in a glove box for 60 minutes, and cooling naturally to obtain a perovskite layer having the same thickness as in Example 1;

[0171] Step S4 is the same as step S4 in Example 1;

[0172] Step S5 is the same as step S5 in Example 1;

[0173] Thus, a perovskite solar cell with an upright structure provided in this comparative example was obtained, which was recorded as C-1.

[0174] Comparative Example 2

[0175] This comparative example provides Figure 1B The preparation method of the inverted structure perovskite solar cell shown.

[0176] Steps S1 to S2 are the same as steps S1 to S2 in Example 1;

[0177] Step S3, including steps S3-1 to S3-2;

[0178] Step S3-1 is the same as step S3-1 in Example 1;

[0179] Step S3-2, preparing a perovskite layer: spin-coating a perovskite precursor solution on the electron transport layer obtained in step S2 at 6000 rpm for 35 seconds, adding 150 μL of ethyl acetate antisolvent at the 20th second countdown, annealing on a hot plate at 100° C. in a glove box for 60 minutes, and cooling naturally to obtain a perovskite layer having the same thickness as in Example 1;

[0180] Step S4 is the same as step S4 in Example 1;

[0181] Step S5 is the same as step S5 in Example 1;

[0182] Thus, an inverted perovskite solar cell provided in this comparative example was obtained, which was recorded as C-2.

[0183] Comparative Example 3

[0184] This comparative example provides a method for laser processing a perovskite wet film, comprising:

[0185] Steps S1 to S2 are the same as steps S1 to S2 in Example 1;

[0186] Step S3, including steps S3-1 to S3-2;

[0187] Step S3-1 is the same as step S3-1 in Example 1;

[0188] Step S3-2, preparing a perovskite layer: spin-coating a perovskite precursor solution on the electron transport layer obtained in step S2, the spin coating condition is 6000 rpm, the spin coating time is 35 s, and there is no anti-solvent treatment. The prepared perovskite wet film is taken out of the glove box through the transfer chamber, placed under the laser equipment, and a laser drawing (parallel horizontal lines with adjacent spacing of 0.01 mm, a total of 1998 lines) is introduced. The focal length is adjusted to 5 cm, and the perovskite wet film is treated with a 1064 nm near-infrared laser. The process is 20 seconds. After the end, the perovskite intermediate film is annealed on a hot plate at 110 ° C in an air environment (humidity 40%, temperature 25 ° C) for 10 minutes, and then naturally cooled to obtain a perovskite layer with the same thickness as in Example 1.

[0189] Figure 7A and 7B This is a scanning electron microscope photo of the surface of the perovskite layer prepared in Comparative Example 2, where Figure 7B yes Figure 7A A partial enlarged view of .

[0190] Step S4 is the same as step S4 in Example 1.

[0191] Step S5 is the same as step S5 in Example 1.

[0192] Thus, the upright perovskite solar cell obtained by laser treatment provided in this embodiment was obtained, which was recorded as C-3.

[0193] Comparative Example 4

[0194] This comparative example provides a method for laser processing a perovskite wet film, comprising:

[0195] Steps S1 to S2 are the same as steps S1 to S2 in Example 2;

[0196] Step S3, including steps S3-1 to S3-2;

[0197] Step S3-1 is the same as step S3-1 in Example 2;

[0198] Step S3-2, preparing a perovskite layer: spin-coating a perovskite precursor solution on the hole transport layer obtained in step S2, the spin coating condition is 6000 rpm, the spin coating time is 35 s, and there is no anti-solvent treatment. The prepared perovskite wet film is taken out of the glove box through the transfer chamber, placed under the laser equipment, and a laser drawing (parallel horizontal lines with adjacent spacing of 0.01 mm, a total of 1998 lines) is introduced. The focal length is adjusted to 5 cm, and the perovskite wet film is treated with a 1064 nm near-infrared laser. The process is 20 seconds. After the end, the perovskite intermediate film is annealed on a hot plate at 110 ° C in an air environment (humidity 40%, temperature 25 ° C) for 10 minutes, and then naturally cooled to obtain a perovskite layer with the same thickness as Example 2.

[0199] Step S4 is the same as step S4 in Example 2.

[0200] Step S5 is the same as step S5 in Example 2.

[0201] Thus, the inverted perovskite solar cell obtained by laser treatment provided in this embodiment was obtained, which was recorded as C-4.

[0202] Comparative Example 5

[0203] This embodiment provides a method for preparing a perovskite solar cell with an upright structure using a dot-matrix laser path, including the following steps:

[0204] Steps S1 to S2 are the same as steps S1 to S2 in Example 1;

[0205] Step S3 is the same as step S3 in Example 1. It is worth noting that the laser drawing introduced after hot plate annealing in this embodiment is a dot matrix laser drawing (such as Figure 8A As shown), it is no longer a waveform drawing. The spacing between each adjacent point in the dot matrix laser drawing is 1mm, the diameter of each point is 0.2mm, a total of 361 points, and the focal distance of the laser equipment is 5cm.

[0206] The percentage of the lattice to the total area of ​​the perovskite layer is calculated as follows:

[0207] The area of ​​all points in the lattice is 361*π*(0.1) 2 =11.34mm 2 , the area ratio is 11.34 / 400=2.83%.

[0208] Step S4 is the same as step S4 in Example 1.

[0209] Step S5 is the same as step S5 in Example 1.

[0210] Thus, a perovskite solar cell with an upright structure prepared using a dot-matrix laser path was obtained, which was provided in this embodiment and was recorded as C-5.

[0211] Comparative Example 6

[0212] This embodiment provides a method for preparing a perovskite solar cell with an upright structure using a linear laser path, including the following steps:

[0213] Steps S1 to S2 are the same as steps S1 to S2 in Example 1;

[0214] Step S3 is the same as step S3 in Example 1. It is worth noting that the laser drawing introduced after hot plate annealing in this embodiment is a linear laser drawing (such as Figure 8B As shown), it is no longer a wavy curve drawing. The spacing between each adjacent straight line in the linear laser drawing is 0.01mm, with a total of 1998 lines, and the focal distance of the laser equipment is 5cm.

[0215] The percentage of the straight grooves to the total area of ​​the perovskite layer is calculated as follows:

[0216] The total area of ​​the linear groove is 1998*20*0.002=79.92mm 2 , the area accounts for 79.92 / 400=19.98%.

[0217] Step S4 is the same as step S4 in Example 1.

[0218] Step S5 is the same as step S5 in Example 1.

[0219] Thus, a perovskite solar cell with an upright structure prepared using a linear laser path was obtained, which was provided in this embodiment and was recorded as C-6.

[0220] Test Example 1

[0221] The performance parameters of the perovskite solar cells prepared in the above examples and comparative examples were tested using standard test conditions (1000 W / m 2, AM 1.5G spectrum), the performance parameters of the perovskite solar cell were obtained by measuring the JV curve under this standard test condition in ambient air. The test results are shown in Table 1 below.

[0222] Table 1

[0223]

[0224]

[0225]

[0226] From the test results in Table 1, it can be seen that when the laser treatment is performed using a waveform curve path and the laser beam is not perpendicular to the surface of the perovskite film, the photovoltaic performance parameters of the perovskite solar cell prepared by the laser-treated perovskite layer are improved, and the stability is also improved.

[0227] The present application has been described above in conjunction with preferred embodiments, but these embodiments are merely exemplary and serve only as an illustrative example. On this basis, various replacements and improvements can be made to the present application, all of which fall within the scope of protection of the present application.

Claims

1. A method for preparing a perovskite layer, characterized in that: The steps include: (1) providing a perovskite film; (2) placing the perovskite film on a processing table so that a certain inclination angle is formed between the vertical line of the film surface and the incident direction of the laser beam; (3) using a laser beam to scan the surface of the perovskite film in a curved path to form a plurality of periodically distributed wavy grooves to obtain a perovskite layer with a surface microstructure; Wherein, the curved path includes a plurality of waveform curves.

2. The preparation method according to claim 1, characterized in that The angle between the laser beam and the perpendicular to the surface of the perovskite film is 10 to 40 degrees, preferably 15 to 30 degrees; The depth of the corrugated groove is 40 to 60 nm and the width is 2 to 7 nm; and / or The total area of ​​the corrugated grooves on the perovskite layer accounts for 20% to 40% of the total area of ​​the perovskite layer.

3. The preparation method according to claim 1, characterized in that The multiple waveform curves are sine curves and / or cosine curves, the angle between the center lines of any two of the multiple waveform curves is 0-5°, and the center lines of the multiple waveform curves are substantially perpendicular to one side of the perovskite film.

4. The preparation method according to claim 3, characterized in that The distance between two adjacent wavy curves is 0.005-0.03 mm.

5. The preparation method according to claim 1, characterized in that The perovskite film is prepared as follows: A perovskite wet film is formed on a substrate, and then the obtained perovskite wet film is subjected to laser annealing and air hot plate annealing to obtain the perovskite thin film.

6. A perovskite solar cell, characterized in that: The perovskite layer comprises a perovskite layer prepared by the preparation method according to any one of the preceding claims.

7. The perovskite solar cell according to claim 6, characterized in that The perovskite solar cell further includes a conductive substrate, an electron transport layer, a hole transport layer and an electrode layer, and the perovskite layer is arranged between the electron transport layer and the hole transport layer.

8. The perovskite solar cell according to claim 7, characterized in that The perovskite layer is disposed on the electron transport layer or the hole transport layer.

9. The perovskite solar cell according to claim 7, characterized in that The perovskite solar cell is an upright perovskite solar cell, comprising a conductive substrate, an electron transport layer, a hole transport layer and an electrode layer, wherein the perovskite layer is disposed on the electron transport layer; The conductive substrate is ITO and / or FTO; The thickness of the electron transport layer is 15 to 25 nm; The thickness of the perovskite layer is 300 to 700 nm; The thickness of the hole transport layer is 50 to 200 nm; The electrode layer has a thickness of 60 to 150 nm.

10. The perovskite solar cell according to claim 7, characterized in that The perovskite solar cell is an inverted perovskite solar cell, comprising a conductive substrate, a hole transport layer, an electron transport layer and an electrode layer, wherein the perovskite layer is disposed on the hole transport layer; The conductive substrate is ITO and / or FTO; The thickness of the hole transport layer is 20 to 40 nm; The thickness of the perovskite layer is 300 to 700 nm; The thickness of the electron transport layer is 20 to 40 nm; The electrode layer has a thickness of 60 to 150 nm.

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