Perovskite solar cell, preparation method thereof and solar cell module

Abstract

The invention relates to the field of perovskite solar cells, and discloses a perovskite solar cell, a preparation method thereof and a solar cell module. The perovskite solar cell comprises a hole transport layer, a functional layer and a perovskite layer which are stacked in sequence. Wherein the functional layer comprises a first functional layer and a second functional layer; the first functional layer and the second functional layer respectively and independently comprise self-assembly molecules. The first functional layer and the second functional layer adjust energy level matching between the hole transport layer and the perovskite layer, passivate interface defects and improve cell performance.

Description

Technical Field

[0001] This invention relates to the field of photovoltaics, specifically to a perovskite solar cell, its preparation method, and a solar cell module. Background Technology

[0002] Perovskite solar cells still suffer from numerous defects at the interface, resulting in strong nonradiative recombination losses that limit the open-circuit voltage (Voc) and fill factor (FF), hindering further performance improvements. Furthermore, the high defect density and ion migration at the interface severely impair the long-term stability of the device, limiting the commercialization of perovskite solar cells. Summary of the Invention

[0003] In view of this, this application provides a perovskite solar cell and its preparation method, as well as a solar cell module. By introducing a first functional layer and a second functional layer including self-assembled molecules, this application adjusts the energy level matching between the hole transport layer and the perovskite layer, reduces interfacial recombination loss, and thus improves the battery performance.

[0004] In a first aspect, this application provides a perovskite solar cell, the perovskite solar cell comprising a hole transport layer, a functional layer and a perovskite layer stacked sequentially; wherein, the functional layer comprises a first functional layer and a second functional layer; the first functional layer and the second functional layer each independently comprise self-assembled molecules.

[0005] Optionally, the perovskite solar cell includes a hole transport layer, a first functional layer, a second functional layer, and a perovskite layer stacked sequentially. The first functional layer includes a first self-assembled molecule, and the second functional layer includes a second self-assembled molecule. The surface wettability of the first functional layer is greater than that of the second functional layer. And / or, the dipole moment of the second self-assembled molecule is greater than that of the first self-assembled molecule.

[0006] Optionally, the contact angle of the first functional layer is less than or equal to 65°, and the contact angle of the second functional layer is greater than or equal to 70°; and / or, the dipole moment of the second self-assembled molecule is greater than or equal to 1.5D, and the dipole moment of the first self-assembled molecule is less than or equal to 1.0D.

[0007] Optionally, the first self-assembled molecule includes MeO-2PACz and / or 2PACz; and / or, the second self-assembled molecule includes one or more of Me-4PACz, Ph-4PACz, 4PADCB, MeO-4PADCB, and DMAcPA.

[0008] Optionally, the first self-assembled molecule is MeO-2PACz, and the second self-assembled molecule is Me-4PACz.

[0009] Optionally, the thickness of the first functional layer is 3-5 nm, and / or the thickness of the second functional layer is 3-5 nm.

[0010] Optionally, the perovskite solar cell further includes a first passivation layer disposed between the functional layer and the perovskite layer, the first passivation layer comprising PFN-Br.

[0011] Optionally, the first passivation layer further includes PEAI, wherein the mass ratio of PEAI to PFN-Br is (8-10):1; and / or, the thickness of the first passivation layer is 5-10 nm.

[0012] Optionally, the perovskite solar cell further includes a second passivation layer disposed on the surface of the perovskite layer away from the functional layer, the second passivation layer comprising methylammonium thiocyanate.

[0013] Optionally, the second passivation layer further includes PEAI, wherein the mass ratio of PEAI to ammonium thiocyanate is (2-5):1; and / or, the thickness of the second passivation layer is 5-10 nm.

[0014] Optionally, the hole transport layer comprises NiOx, and / or the thickness of the hole transport layer is 10-20 nm.

[0015] Optionally, the perovskite solar cell further includes a transparent conductive substrate located on the surface of the hole transport layer away from the perovskite layer.

[0016] Optionally, the perovskite solar cell includes, from bottom to top, the transparent conductive substrate, the hole transport layer, the first functional layer, the second functional layer, the first passivation layer, the perovskite layer, the second passivation layer, the electron transport layer, the hole blocking layer, and the metal electrode, which are stacked sequentially.

[0017] Secondly, this application provides a method for preparing a perovskite solar cell as described in the first aspect of this application, comprising the following steps: S1, coating a first self-assembled molecular alcohol solution onto the surface of a hole transport layer and performing a first annealing treatment to obtain a first functional layer; S2, coating a second self-assembled molecular alcohol solution onto the surface of the first functional layer and performing a second annealing treatment to obtain a second functional layer; S3, preparing a perovskite layer on the surface of the second functional layer.

[0018] Optionally, the concentration of the first self-assembled molecule in the first self-assembled molecule alcohol solution is 0.3-0.5 mg / mL, and / or the first self-assembled molecule includes MeO-2PACz and / or 2PACz; and / or, the concentration of the second self-assembled molecule in the second self-assembled molecule alcohol solution is 0.3-0.5 mg / mL, and / or the second self-assembled molecule includes one or more of Me-4PACz, Ph-4PACz, 4PADCB, MeO-4PADCB and DMAcPA.

[0019] Optionally, in step S1, the coating is performed by spin coating at a speed of 2000-5000 rpm for 20-40 seconds; and / or, the temperature of the first annealing treatment is 100-110°C, and the time of the first annealing treatment is 5-15 minutes.

[0020] Optionally, in step S2, the coating is performed by spin coating at a speed of 2000-5000 rpm for 20-40 seconds; and / or, the temperature of the second annealing treatment is 100-110°C, and the time of the second annealing treatment is 5-15 minutes.

[0021] Optionally, the method further includes the preparation of a first passivation layer: coating the surface of the second functional layer with a first mixed solution to obtain the first passivation layer; the first mixed solution includes PFN-Br.

[0022] Optionally, the first mixed solution comprises PEAI and PFN-Br, wherein the mass ratio of PEAI to PFN-Br is (8-10):1.

[0023] Optionally, the method further includes the preparation of a second passivation layer: coating the surface of the perovskite layer with a second mixed solution to obtain the second passivation layer; the second mixed solution includes methyl ammonium thiocyanate.

[0024] Optionally, the second mixed solution comprises PEAI and methyl ammonium thiocyanate, wherein the mass ratio of PEAI to methyl ammonium thiocyanate is (2-5):1.

[0025] Thirdly, this application provides a solar cell module, including the perovskite solar cell described in the first aspect of this application.

[0026] Through the above technical solution, this application introduces self-assembled molecules as a first functional layer and a second functional layer. The first and second functional layers are located between the hole transport layer and the perovskite layer. The functional layers can adjust the energy level matching between the hole transport layer and the perovskite layer, reducing voltage loss caused by energy level mismatch. Furthermore, the functional layers can fill interface defects between the hole transport layer and the perovskite layer, reducing interface recombination losses and improving charge transport efficiency. This helps to improve the overall performance and stability of the battery.

[0027] Other features and advantages of this application will be described in detail in the following detailed description section. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 This is a schematic diagram of the structure of the perovskite solar cell provided in the embodiments of this application.

[0030] Figure 2 These are the JV characteristic curves of the batteries corresponding to Example 8 and Comparative Example 3.

[0031] Figure 3 It is the equivalent circuit model used to measure electrochemical AC impedance spectroscopy.

[0032] Figure 4 These are the electrochemical impedance spectroscopy spectra of the batteries corresponding to Example 8 and Comparative Example 3.

[0033] Explanation of reference numerals in the attached figures: 1-Transparent conductive substrate, 2-Hole transport layer, 3-First functional layer, 4-Second functional layer, 5-First passivation layer, 6-Perovskite layer, 7-Second passivation layer, 8-LiF passivation layer, 9-Electron transport layer, 10-Hole blocking layer, 11-Metal electrode. Detailed Implementation

[0034] The technical solutions in the embodiments of this application are described clearly and completely below. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0035] This application provides a perovskite solar cell, comprising a hole transport layer, a functional layer, and a perovskite layer stacked sequentially. The functional layer includes a first functional layer and a second functional layer; both the first and second functional layers include self-assembled molecules. Specifically, the functional layer is located between the hole transport layer and the perovskite layer. These self-assembled molecules can adjust the energy level matching between the hole transport layer and the perovskite layer, reducing voltage loss due to energy level mismatch. The functional layer can also fill or passivate interface defects between the hole transport layer and the perovskite layer, reducing interface recombination loss and improving charge transport efficiency. This contributes to improving the overall performance and stability of the cell. Furthermore, certain self-assembled molecules (such as MeO-4PADCB containing phosphonic acid groups and carbazole rings) can form reinforcing bonds with the NiOx surface, thereby enhancing the bonding force between the functional layer and NiOx. This enhanced bonding force not only helps improve the stability of the cell but also resists interface degradation caused by high temperature and light exposure.

[0036] Self-assembled molecules refer to the process by which molecules spontaneously organize or aggregate into aggregates or supramolecular structures with specific structures and functions through intermolecular interactions without external human intervention. Different self-assembled molecules have different chemical structures and properties, which directly affect the surface properties of the functional layers they form. In this application, self-assembled molecules for functional layers are designed to improve battery performance.

[0037] In some embodiments, a perovskite solar cell includes a hole transport layer, a first functional layer, a second functional layer, and a perovskite layer stacked sequentially. The first functional layer includes a first self-assembled molecule, and the second functional layer includes a second self-assembled molecule. The surface wettability of the first functional layer is greater than that of the second functional layer. Surface wettability refers to the ability or tendency of a liquid to spread on a solid surface, which is influenced by both the chemical composition and microstructure of the solid surface. A surface with good wettability allows the liquid to spread easily; conversely, a surface with poor wettability is difficult to spread. Furthermore, the contact angle, the angle formed when a liquid contacts a solid surface, is a key indicator for evaluating the wettability of a solid. The size of the contact angle directly reflects the degree of liquid spread on the solid surface. Specifically, a smaller contact angle indicates better wettability and more complete liquid spread on the solid surface; a larger contact angle indicates poorer wettability and more difficult liquid spread on the solid surface. That is, the contact angle of the first functional layer is smaller than that of the second functional layer. The high wettability of the first functional layer is beneficial for improving the contact quality between it and the hole transport layer, thereby reducing interfacial resistance and charge recombination losses.

[0038] In some embodiments, the dipole moment of the second self-assembled molecule is greater than that of the first self-assembled molecule. The dipole moment is a physical quantity that measures the polarity of a molecule; it represents the product of the distance between the centers of positive and negative charges and the amount of charge. A larger dipole moment indicates stronger molecular polarity. Molecules with stronger polarity generally have better solubility and interfacial interaction capabilities, which helps improve the contact quality between the functional layer and its adjacent layers. Since the second functional layer is adjacent to the perovskite layer, the magnitude of its dipole moment directly affects the interfacial interaction with the perovskite layer. If the dipole moments of the second functional layer and the perovskite layer match, their interaction may be stronger, thus contributing to the formation of a tighter and more stable interface. This strong interaction helps reduce interfacial defects and charge recombination, increasing the charge transport rate. Furthermore, the magnitude of the dipole moment also affects the charge transport efficiency between layers. In solar cells, efficient charge transport is one of the key steps in the photoelectric conversion process. If the dipole moments between adjacent layers are designed properly, charge transport at the interface can be smoother, reducing energy loss and charge recombination during transport, thereby improving the photoelectric conversion efficiency of the cell. By designing and optimizing the dipole moment of the functional layer, precise control of battery performance can be achieved.

[0039] In some embodiments, the functional layers of a perovskite solar cell simultaneously satisfy the following conditions: the surface wettability of the first functional layer is greater than that of the second functional layer, and the dipole moment of the second self-assembled molecule is greater than that of the first self-assembled molecule. The high wettability of the first functional layer improves the contact quality between the perovskite layer and the hole transport layer, thereby reducing interfacial resistance and charge recombination losses; the optimized dipole moment design of the first and second functional layers optimizes charge transport between the hole transport layer and the perovskite layer, resulting in smoother charge transport at the interface.

[0040] In some embodiments, the contact angle of the first functional layer is less than or equal to 65°, and the contact angle of the second functional layer is greater than or equal to 70°. In this application, the test solution for the contact angle is ultrapure water, meaning that the contact angle of ultrapure water in the first functional layer is less than or equal to 65°, and the contact angle of ultrapure water in the second functional layer is greater than or equal to 70°. The difference between the water contact angles of the first and second functional layers indicates that the first functional layer substrate has better wettability, which helps in the formation of high-quality perovskite films.

[0041] In some embodiments, the dipole moment of the second self-assembled molecules included in the second functional layer is greater than or equal to 1.5D, and the dipole moment of the first self-assembled molecules included in the first functional layer is 0-1.0D. In perovskite solar cells, the interface between different materials often affects current transport. When materials with large differences in dipole moments come into contact, special interface structures may be formed. These structures affect the charge injection, transport, and collection processes, thereby indirectly affecting the magnitude and efficiency of the current. This application optimizes the interface performance by introducing a first functional layer and a second functional layer between the perovskite layer and the hole transport layer.

[0042] In some embodiments, the functional layers of the perovskite solar cell simultaneously satisfy the following conditions: the water contact angle of the first functional layer is less than or equal to 65°, and the water contact angle of the second functional layer is greater than or equal to 70°; the dipole moment of the second self-assembled molecule is greater than or equal to 1.5D, and the dipole moment of the first self-assembled molecule is 0-1.0D. This improves interface defects and enhances cell performance in two ways. Further, the water contact angle of the second functional layer is preferably 80-100°.

[0043] In some embodiments, the first self-assembled molecule comprises MeO-2PACz ([2-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl]phosphonic acid) and / or 2PACz ([2-(9H-carbazole-9-yl)ethyl]phosphonic acid); the second self-assembled molecule comprises Me-4PACz ([4-(3,6-dimethyl-9H-carbazole-9-yl)butyl]phosphate), Ph-4PACz ([4-(3,6-dimethyl-9H-carbazole-9-yl)butyl]phosphate), and / or 2PACz ([4-(3,6-dimethyl-9H-carbazole-9-yl)butyl]phosphate). The first self-assembled molecule can be one or more of the following: [6-diphenyl-9H-carbazole-9-yl)butyl]phosphoric acid, [4-(7H-dibenzocarbazole-7-yl)butyl]phosphoric acid, [MeO-4PADCB-4-phosphoric acid, [4-(3,11-dimethoxy-7H-dibenzo[c,g]carbazole-7-yl)butyl]phosphoric acid, and [DMAcPA-4-(2,7-dibromo-9,9-dimethylacridin-10(9H)-yl)butyl]phosphonic acid. Specifically, the first self-assembled molecule can be MeO-2PACz, 2PACz, or a combination of both. The second self-assembled molecule can be Me-4PACz, Ph-4PACz, 4PADCB, MeO-4PADCB, DMAcPA, or any combination thereof. Furthermore, in order to better improve battery performance, the first self-assembled molecule is preferably MeO-2PACz, and the second self-assembled molecule is preferably Me-4PACz.

[0044] In some embodiments, the first self-assembled molecule is MeO-2PACz with a dipole moment of ~0.2D, and the second self-assembled molecule is Me-4PACz with a dipole moment of ~1.7D; that is, the first functional layer is MeO-2PACz and the second functional layer is Me-4PACz. In this case, the water contact angle of the first functional layer is ~65°, and the water contact angle of the second functional layer is 85°. MeO-2PACz, with its hydrophilic methoxy groups, can provide better wettability for the deposition of the perovskite light-absorbing layer, while Me-4PACz, with its larger dipole moment, is beneficial for obtaining good band matching at the hole transport layer / perovskite layer interface. Therefore, the combination of MeO-2PACz / Me-4PACz can effectively achieve complete coverage of the perovskite layer and the extraction and transport of holes.

[0045] In some implementations, the thickness of the first functional layer is 3-5 nm, and the thickness of the second functional layer is 3-5 nm. The thicknesses of the first and second functional layers are within this range, allowing the overall functional layers to achieve a balance between wettability and polarity, thus better improving battery performance.

[0046] In some embodiments, the hole transport layer comprises NiOx, and the thickness of the hole transport layer is 10-20 nm. The NiOx / MeO-2PACz / Me-4PACz / perovskite layer structure, with its two functional layers, avoids incomplete coverage of the NiOx layer due to the perovskite precursor solution washing away a single functional layer, thus preventing pinholes. It also avoids direct contact between the perovskite layer and the transparent conductive substrate, and further prevents the active Ni in the NiOx layer from being washed away. 3+ The reaction with perovskite reduces defects and suppresses non-radiative recombination at the buried interface, thus significantly improving the fill factor of perovskite solar cells.

[0047] In some embodiments, the perovskite solar cell further includes a first passivation layer disposed between the functional layer and the perovskite layer. That is, the perovskite solar cell comprises a hole transport layer, a first functional layer, a second functional layer, a first passivation layer, and a perovskite layer stacked sequentially. The thickness of the first passivation layer is 5-10 nm. The first passivation layer includes PFN-Br for passivating the perovskite buried interface. PFN-Br is a conjugated electrolyte that facilitates the formation of the perovskite phase and the growth of perovskite crystals. Furthermore, PFN-Br has long hydrophobic polymer chains that can suppress moisture ingress, preventing perovskite degradation at the buried interface due to moisture penetration and thus protecting the long-term stability of the perovskite solar cell.

[0048] In some embodiments, the perovskite solar cell further includes a second passivation layer disposed on the surface of the perovskite layer away from the hole transport layer. That is, the solar cell includes a hole transport layer, a first functional layer, a second functional layer, a perovskite layer, and a second passivation layer stacked sequentially. The thickness of the second passivation layer is 5-10 nm. The second passivation layer includes methylammonium thiocyanate (MASCN) for passivating the top interface of the perovskite layer. Furthermore, when using MASCN to passivate the surface of the perovskite layer away from the hole transport layer, due to the… − Ionic radius and I - Similar, some SCN − It can diffuse along the grain boundaries towards the buried interface of the perovskite, promoting the more effective penetration of other passivating agents (such as PEAI) into the perovskite layer, thereby achieving effective passivation of the perovskite layer. Meanwhile, methylamine ions, under the promotion of SCN-, partially enter the lattice of the perovskite surface layer, while the remainder stays on the surface of the perovskite layer to fill defects.

[0049] In some embodiments, the first passivation layer and the second passivation layer further include PEAI. In the first passivation layer, the mass ratio of PEAI to PFN-Br is (8-10):1, specifically, the mass ratio of PEAI to PFN-Br can be 10:1; in the second passivation layer, the mass ratio of PEAI to MASCN is (2-5):1, specifically, the mass ratio of PEAI to MASCN can be 4:1. PEAI, in molecular form, covers the upper and lower surfaces of the perovskite layer, filling iodine vacancies on the surface, thereby reducing defects on the upper and lower surfaces of the perovskite and suppressing non-radiative recombination.

[0050] In some embodiments, the perovskite solar cell further includes a transparent conductive substrate located on the surface of the hole transport layer away from the perovskite layer, i.e., the perovskite solar cell is an inverted structure. Inverted perovskite solar cells exhibit low hysteresis, good interface stability, and maintain good performance stability even after long-term optimization.

[0051] In some embodiments, the perovskite layer includes the use of microcrystalline additives, the microcrystalline additives having the general formula ABX3, where the A-site ion can be MA. + FA + Cs + The B-site ion can be Pb. 2+ Sn 2+Alternatively, a combination of both can be used, where the X-site ion can be a halide ion or any combination of two halide ions. Furthermore, MAPbI₂Cl microcrystals are preferred, replacing the common methylamine chloride (MACl) as the passivating agent for the perovskite layer. This provides nucleation sites, increases grain size, and optimizes crystal orientation, thereby obtaining a high-quality perovskite film with better crystal orientation and fewer defects, significantly improving the open-circuit voltage of the battery.

[0052] In some implementations, such as Figure 1 As shown, the perovskite solar cell comprises, from bottom to top, a transparent conductive substrate, a hole transport layer, a first functional layer, a second functional layer, a first passivation layer, a perovskite layer, a second passivation layer, a LiF passivation layer, an electron transport layer, a hole blocking layer, and a metal electrode, stacked sequentially. The materials used for the transparent conductive substrate, electron transport layer, hole blocking layer, and metal electrode can be conventionally chosen in the art, and this application does not impose any limitations on them. The perovskite solar cell has an inverted structure, significantly reducing the defect density at the first passivation layer / perovskite layer interface, the second passivation layer / perovskite layer interface, and the perovskite bulk phase. This increases the recombination resistance of the device, suppresses non-radiative recombination at the interface, and improves the open-circuit voltage and fill factor of the inverted perovskite solar cell.

[0053] This application also provides a method for preparing a perovskite solar cell, comprising the following steps: S1, coating a first self-assembled molecular alcohol solution onto the surface of a hole transport layer and performing a first annealing treatment to obtain a first functional layer; S2, coating a second self-assembled molecular alcohol solution onto the surface of the first functional layer and performing a second annealing treatment to obtain a second functional layer; S3, preparing a perovskite layer on the surface of the second functional layer.

[0054] In some embodiments, the concentration of the first self-assembled molecule in the first self-assembled molecule alcohol solution is 0.3-0.5 mg / mL, the solvent can be ethanol, and the first self-assembled molecule includes MeO-2PACz and / or 2PACz. Specifically, the concentration of the first self-assembled molecule in the first self-assembled molecule alcohol solution can be 0.3 mg / mL, 0.4 mg / mL, or 0.5 mg / mL.

[0055] In some embodiments, the concentration of the second self-assembled molecule in the alcoholic solution is 0.3-0.5 mg / mL, the solvent can be ethanol, and the second self-assembled molecule includes one or more of Me-4PACz, Ph-4PACz, 4PADCB, MeO-4PADCB, and DMAcPA. Specifically, the concentration of the second self-assembled molecule in the alcoholic solution can be 0.3 mg / mL, 0.4 mg / mL, or 0.5 mg / mL.

[0056] In some embodiments, in step S1, the coating is performed by spin coating at a speed of 2000-5000 rpm for 20-40 seconds; the temperature of the first annealing treatment is 100-110°C, and the time of the first annealing treatment is 5-15 minutes. Specifically, the coating can be performed by spin coating at a speed of 3000 rpm for 30 seconds, followed by annealing on a hot plate at 100°C for 10 minutes to obtain the first functional layer.

[0057] In some embodiments, in step S2, the coating is performed by spin coating at a speed of 2000-5000 rpm for 20-40 seconds; the temperature of the second annealing treatment is 100-110°C, and the time of the second annealing treatment is 5-15 minutes. Specifically, the second functional layer can be obtained by spin coating at a speed of 3000 rpm for 30 seconds and then annealing on a hot plate at 100°C for 10 minutes.

[0058] In some embodiments, the preparation method further includes the preparation of a first passivation layer: dissolving PEAI and PFN-Br in isopropanol, wherein the mass ratio of PEAI to PFN-Br is (8-10):1, to prepare a first mixed solution; spin-coating the first mixed solution onto the surface of the second functional layer at a speed of 4000-6000 rpm for 20-40 s, without annealing, to obtain the first passivation layer.

[0059] In some embodiments, the preparation method further includes the preparation of a second passivation layer: PEAI and MASCN are dissolved in a mixed solvent of isopropanol (IPA) and N,N-dimethylformamide (DMF) (the volume ratio of IPA to DMF is 100-200:1), and the mass ratio of PEAI to MASCN is (2-5):1, to prepare a second mixed solution; the second mixed solution is spin-coated onto the surface of the perovskite layer at a speed of 4000-6000 rpm for 20-40 s without annealing treatment to obtain the second passivation layer.

[0060] In some embodiments, the hole transport layer is NiOx, and its preparation method includes: preparing an aqueous solution of NiOx with a concentration of 8-12 mg / mL; adding 5-20 μL of H2O2 to each 1 mL of the NiOx solution for oxidation treatment to obtain a hole transport layer solution; spin-coating the solution onto a transparent conductive glass surface at a speed of 2000-5000 rpm; and annealing the solution on a hot plate at 100-150℃ for 10-20 min. Treating NiOx with H2O2 can optimize the self-assembly of self-assembled molecules on NiOx and improve the conductivity of NiOx.

[0061] In some embodiments, the perovskite layer includes the use of microcrystalline additives. Specifically, 5 mol%-15 mol% of methylamine lead chloride iodide (MAPbI2Cl) microcrystalline additive is added to the perovskite precursor solution and dissolved by heating on a hot stage at 40-60°C to obtain a perovskite solution. The preparation process of the perovskite layer includes: spin-coating the perovskite solution onto the substrate surface at a speed of 1000-2000 rpm for 5-15 s, then spin-coating the perovskite solution at a speed of 4000-6000 rpm for 30-50 s, adding an appropriate amount of antisolvent ethyl acetate dropwise when the spin-coating is in progress for 30-40 s, and then heating at 100-130°C for 10-30 min.

[0062] This application also provides a solar cell module, which includes the perovskite solar cell described above.

[0063] The effects of the technical solution in this application will be further illustrated below with specific examples.

[0064] Example 1 S1 and FTO glass were ultrasonically cleaned for 10 minutes each with dish soap water, ultrapure water and anhydrous ethanol, then dried with N2 air gun and plasma treated for 8 minutes in an oxygen atmosphere. S2. Take a NiOx solution with a concentration of 10 mg / mL and spread it on the surface of the FTO substrate. Spin-coat at 3000 rpm for 30 s and anneal on a hot plate at 150℃ for 10 min to obtain a hole transport layer with a thickness of 20 nm. S3. After the FTO substrate cools to room temperature, transfer it to a glove box filled with nitrogen. Spread an anhydrous ethanol solution of MeO-2PACz (dipole moment ~0.2D) at a concentration of 0.3 mg / mL onto the surface of the hole transport layer. Spin-coat at 3000 rpm for 30 s and anneal on a hot plate at 100℃ for 10 min to obtain the first functional layer. The thickness of the first functional layer is 3 nm and the water contact angle is ~65°. S4. Take an anhydrous ethanol solution of Me-4PACz with a concentration of 0.3 mg / mL (dipole moment of ~1.7D) and spread it on the surface of the first functional layer. Spin-coat at 3000 rpm for 30 s and anneal on a hot plate at 100℃ for 10 min to obtain the second functional layer. The thickness of the second functional layer is 3 nm and the water contact angle is ~85°. S5. Take the perovskite precursor solution and spread it on the surface of the second functional layer. First spin coat it at 2000 rpm for 10 s, then spin coat it at 5000 rpm for 40 s. When spin coating is carried out for 35 s, add 150 μL of the anti-solvent ethyl acetate. Heat the perovskite wet film on a hot stage at 120 ℃ for 20 min. The thickness of the perovskite layer is 650 nm. S6. A LiF passivation layer with a thickness of 1 nm is deposited by vapor deposition at a rate of 0.05 Å / s. S7. A C60 electron transport layer with a thickness of 30 nm is deposited at a rate of 0.15 Å / s. S8, vapor-deposited Ag electrode, with a thickness of 140nm.

[0065] Example 2 S1 and FTO glass were ultrasonically cleaned for 10 minutes each with dish soap water, ultrapure water and anhydrous ethanol, then dried with N2 air gun and plasma treated for 8 minutes in an oxygen atmosphere. S2. Take a NiOx solution with a concentration of 10 mg / mL and spread it on the surface of the FTO substrate. Spin-coat at 3000 rpm for 30 s and anneal on a hot plate at 150℃ for 10 min to obtain a hole transport layer with a thickness of 20 nm. S3. After the FTO substrate cools to room temperature, transfer it to a glove box filled with nitrogen. Spread an anhydrous ethanol solution of MeO-2PACz (dipole moment ~0.2D) at a concentration of 0.4 mg / mL onto the surface of the hole transport layer. Spin-coat at 3000 rpm for 30 s and anneal on a hot plate at 100℃ for 10 min to obtain the first functional layer. The thickness of the first functional layer is 4 nm and the water contact angle is ~63°. S4. Take an anhydrous ethanol solution of Me-4PACz with a concentration of 0.4 mg / mL (dipole moment of ~1.7D) and spread it on the surface of the first functional layer. Spin-coat at 3000 rpm for 30 s and anneal on a hot plate at 100℃ for 10 min to obtain the second functional layer. The thickness of the second functional layer is 4 nm and the water contact angle is ~87°. S5. Take the perovskite precursor solution and spread it on the surface of the second functional layer. First spin coat it at 2000 rpm for 10 s, then spin coat it at 5000 rpm for 40 s. When spin coating is carried out for 35 s, add 150 μL of the anti-solvent ethyl acetate. Heat the perovskite wet film on a hot stage at 120 ℃ for 20 min. The thickness of the perovskite layer is 650 nm. S6. A LiF passivation layer with a thickness of 1 nm is deposited by vapor deposition at a rate of 0.05 Å / s. S7. A C60 electron transport layer with a thickness of 30 nm is deposited at a rate of 0.15 Å / s. S8, vapor-deposited Ag electrode, with a thickness of 140nm.

[0066] Example 3 S1 and FTO glass were ultrasonically cleaned for 10 minutes each with dish soap water, ultrapure water and anhydrous ethanol, then dried with N2 air gun and plasma treated for 8 minutes in an oxygen atmosphere. S2. Take a NiOx solution with a concentration of 10 mg / mL and spread it on the surface of the FTO substrate. Spin-coat at 3000 rpm for 30 s and anneal on a hot plate at 150℃ for 10 min to obtain a hole transport layer with a thickness of 20 nm. S3. After the FTO substrate cools to room temperature, transfer it to a glove box filled with nitrogen. Spread an anhydrous ethanol solution of MeO-2PACz (dipole moment ~0.2D) at a concentration of 0.5 mg / mL onto the surface of the hole transport layer. Spin-coat at 3000 rpm for 30 s and anneal on a hot plate at 100℃ for 10 min to obtain the first functional layer. The thickness of the first functional layer is 5 nm and the contact angle is ~62°. S4. Take an anhydrous ethanol solution of Me-4PACz with a concentration of 0.5 mg / mL (dipole moment of ~1.7D) and spread it on the surface of the first functional layer. Spin-coat at 3000 rpm for 30 s and anneal on a hot plate at 100℃ for 10 min to obtain the second functional layer. The thickness of the second functional layer is 5 nm and the contact angle is ~88°. S5. Take the perovskite precursor solution and spread it on the surface of the second functional layer. First spin coat it at 2000 rpm for 10 s, then spin coat it at 5000 rpm for 40 s. When spin coating is carried out for 35 s, add 150 μL of the anti-solvent ethyl acetate. Heat the perovskite wet film on a hot stage at 120 ℃ for 20 min. The thickness of the perovskite layer is 650 nm. S6. A LiF passivation layer with a thickness of 1 nm is deposited by vapor deposition at a rate of 0.05 Å / s. S7. A C60 electron transport layer with a thickness of 30 nm is deposited at a rate of 0.15 Å / s. S8, vapor-deposited Ag electrode, with a thickness of 140nm.

[0067] Example 4 S1 and FTO glass were ultrasonically cleaned for 10 minutes each with dish soap water, ultrapure water and anhydrous ethanol, then dried with N2 air gun and plasma treated for 8 minutes in an oxygen atmosphere. S2. Take a NiOx solution with a concentration of 10 mg / mL and spread it on the surface of the FTO substrate. Spin-coat at 3000 rpm for 30 s and anneal on a hot plate at 150℃ for 10 min to obtain a hole transport layer with a thickness of 20 nm. S3. After the FTO substrate cools to room temperature, transfer it to a glove box filled with nitrogen. Spread an anhydrous ethanol solution of MeO-2PACz (dipole moment ~0.2D) at a concentration of 0.3 mg / mL onto the surface of the hole transport layer. Spin-coat at 3000 rpm for 30 s and anneal on a hot plate at 100℃ for 10 min to obtain the first functional layer. The thickness of the first functional layer is 3 nm and the water contact angle is ~65°. S4. Take an anhydrous ethanol solution of Me-4PACz with a concentration of 0.5 mg / mL (dipole moment of ~1.7D) and spread it on the surface of the first functional layer. Spin-coat at 3000 rpm for 30 s and anneal on a hot plate at 100℃ for 10 min to obtain the second functional layer. The thickness of the second functional layer is 5 nm and the water contact angle is ~88°. S5. Take the perovskite precursor solution and spread it on the surface of the second functional layer. First spin coat it at 2000 rpm for 10 s, then spin coat it at 5000 rpm for 40 s. When spin coating is carried out for 35 s, add 150 μL of the anti-solvent ethyl acetate. Heat the perovskite wet film on a hot stage at 120 ℃ for 20 min. The thickness of the perovskite layer is 650 nm. S6. A LiF passivation layer with a thickness of 1 nm is deposited by vapor deposition at a rate of 0.05 Å / s. S7. A C60 electron transport layer with a thickness of 30 nm is deposited at a rate of 0.15 Å / s. S8, vapor-deposited Ag electrode, with a thickness of 140nm.

[0068] Example 5 S1 and FTO glass were ultrasonically cleaned for 10 minutes each with dish soap water, ultrapure water and anhydrous ethanol, then dried with N2 air gun and plasma treated for 8 minutes in an oxygen atmosphere. S2. Take a NiOx solution with a concentration of 10 mg / mL and spread it on the surface of the FTO substrate. Spin-coat at 3000 rpm for 30 s and anneal on a hot plate at 150℃ for 10 min to obtain a hole transport layer with a thickness of 20 nm. S3. After the FTO substrate cools to room temperature, transfer it to a glove box filled with nitrogen. Spread an anhydrous ethanol solution with a concentration of 0.3 mg / mL 2PACz (dipole moment of ~2D) all over the surface of the hole transport layer. Spin coat at 3000 rpm for 30 s and anneal on a hot plate at 100℃ for 10 min to obtain the first functional layer. The thickness of the first functional layer is 3 nm and the water contact angle is ~64°. S4. Take an anhydrous ethanol solution of Me-4PACz with a concentration of 0.3 mg / mL (dipole moment of ~1.7D) and spread it on the surface of the first functional layer. Spin-coat at 3000 rpm for 30 s and anneal on a hot plate at 100℃ for 10 min to obtain the second functional layer. The thickness of the second functional layer is 3 nm and the water contact angle is ~85°. S5. Take the perovskite precursor solution and spread it on the surface of the second functional layer. First spin coat it at 2000 rpm for 10 s, then spin coat it at 5000 rpm for 40 s. When spin coating is carried out for 35 s, add 150 μL of the anti-solvent ethyl acetate. Heat the perovskite wet film on a hot stage at 120 ℃ for 20 min. The thickness of the perovskite layer is 650 nm. S6. A LiF passivation layer with a thickness of 1 nm is deposited by vapor deposition at a rate of 0.05 Å / s. S7. A C60 electron transport layer with a thickness of 30 nm is deposited at a rate of 0.15 Å / s. S8, vapor-deposited Ag electrode, with a thickness of 140nm.

[0069] Example 6 S1 and FTO glass were ultrasonically cleaned for 10 minutes each with dish soap water, ultrapure water and anhydrous ethanol, then dried with N2 air gun and plasma treated for 8 minutes in an oxygen atmosphere. S2. Take a NiOx solution with a concentration of 10 mg / mL and spread it on the surface of the FTO substrate. Spin-coat at 3000 rpm for 30 s and anneal on a hot plate at 150℃ for 10 min to obtain a hole transport layer with a thickness of 20 nm. S3. After the FTO substrate cools to room temperature, transfer it to a glove box filled with nitrogen. Spread an anhydrous ethanol solution of Me-4PACz (dipole moment ~1.7D) at a concentration of 0.3 mg / mL onto the surface of the hole transport layer. Spin-coat at 3000 rpm for 30 s and anneal on a hot plate at 100℃ for 10 min to obtain the first functional layer. The thickness of the first functional layer is 3 nm and the water contact angle is ~85°. S4. Take an anhydrous ethanol solution of MeO-2PACz with a concentration of 0.3 mg / mL (dipole moment of ~0.2D) and spread it on the surface of the first functional layer. Spin-coat at 3000 rpm for 30 s and anneal on a hot plate at 100℃ for 10 min to obtain the second functional layer. The thickness of the second functional layer is 3 nm and the water contact angle is ~65°. S5. Take the perovskite precursor solution and spread it on the surface of the second functional layer. First spin coat it at 2000 rpm for 10 s, then spin coat it at 5000 rpm for 40 s. When spin coating is carried out for 35 s, add 150 μL of the anti-solvent ethyl acetate. Heat the perovskite wet film on a hot stage at 120 ℃ for 20 min. The thickness of the perovskite layer is 650 nm. S6. A LiF passivation layer with a thickness of 1 nm is deposited by vapor deposition at a rate of 0.05 Å / s. S7. A C60 electron transport layer with a thickness of 30 nm is deposited at a rate of 0.15 Å / s. S8, vapor-deposited Ag electrode, with a thickness of 140nm.

[0070] Example 7 S1 and FTO glass were ultrasonically cleaned for 10 minutes each with dish soap water, ultrapure water and anhydrous ethanol, then dried with N2 air gun and plasma treated for 8 minutes in an oxygen atmosphere. S2. Take a NiOx solution with a concentration of 10 mg / mL and spread it on the surface of the FTO substrate. Spin-coat at 3000 rpm for 30 s and anneal on a hot plate at 150℃ for 10 min to obtain a hole transport layer with a thickness of 20 nm. S3. After the FTO substrate cools to room temperature, transfer it to a glove box filled with nitrogen. Spread an anhydrous ethanol solution of Me-4PACz (dipole moment ~1.7D) at a concentration of 0.3 mg / mL onto the surface of the hole transport layer. Spin-coat at 3000 rpm for 30 s and anneal on a hot plate at 100℃ for 10 min to obtain the first functional layer. The thickness of the first functional layer is 3 nm and the water contact angle is ~85°. S4. Take an anhydrous ethanol solution with a concentration of 0.3 mg / mL of 2PACz (dipole moment of ~2D) and spread it evenly on the surface of the first functional layer. Spin coat it at 3000 rpm for 30 s and anneal it on a hot plate at 100℃ for 10 min to obtain the second functional layer. The thickness of the second functional layer is 3 nm and the water contact angle is ~64°. S5. Take the perovskite precursor solution and spread it on the surface of the second functional layer. First spin coat it at 2000 rpm for 10 s, then spin coat it at 5000 rpm for 40 s. When spin coating is carried out for 35 s, add 150 μL of the anti-solvent ethyl acetate. Heat the perovskite wet film on a hot stage at 120 ℃ for 20 min. The thickness of the perovskite layer is 650 nm. S6. A LiF passivation layer with a thickness of 1 nm is deposited by vapor deposition at a rate of 0.05 Å / s. S7. A C60 electron transport layer with a thickness of 30 nm is deposited at a rate of 0.15 Å / s. S8, vapor-deposited Ag electrode, with a thickness of 140nm.

[0071] Example 8 S1 and FTO glass were ultrasonically cleaned for 10 minutes each with dish soap water, ultrapure water and anhydrous ethanol, then dried with N2 air gun and plasma treated for 8 minutes in an oxygen atmosphere. S2. Take a NiOx solution with a concentration of 10 mg / mL and spread it on the surface of the FTO substrate. Spin-coat at 3000 rpm for 30 s and anneal on a hot plate at 150℃ for 10 min to obtain a hole transport layer with a thickness of 20 nm. S3. After the FTO substrate cools to room temperature, transfer it to a glove box filled with nitrogen. Spread an anhydrous ethanol solution of MeO-2PACz (dipole moment ~0.2D) at a concentration of 0.3 mg / mL onto the surface of the hole transport layer. Spin-coat at 3000 rpm for 30 s and anneal on a hot plate at 100℃ for 10 min to obtain the first functional layer. The thickness of the first functional layer is 3 nm and the water contact angle is ~65°. S4. Take an anhydrous ethanol solution of Me-4PACz with a concentration of 0.3 mg / mL (dipole moment of ~1.7D) and spread it on the surface of the first functional layer. Spin-coat at 3000 rpm for 30 s and anneal on a hot plate at 100℃ for 10 min to obtain the second functional layer. The thickness of the second functional layer is 3 nm and the water contact angle is ~85°. S5. Take a 1.1 mg / mL anhydrous ethanol mixture of PEAI and PFN-Br (mass ratio of PEAI and PFN-Br is 10:1) and add it dropwise to the surface of the second functional layer. Perform dynamic spin coating at 5000 rpm for 30 s without annealing to obtain the first passivation layer with a thickness of 5 nm. S6. Take the perovskite precursor solution and spread it on the surface of the first passivation layer. First spin coat it at 2000 rpm for 10 s, then spin coat it at 5000 rpm for 40 s. When spin coating is carried out for 35 s, add 150 μL of the anti-solvent ethyl acetate. Heat the perovskite wet film on a hot stage at 120 ℃ for 20 min. The thickness of the perovskite layer is 650 nm. S7. Take a PEAI and MASCN (mass ratio of PEAI and MASCN is 4:1) mixed solution of IPA-DMF (volume ratio of IPA and DMF is 100:1) with a concentration of 1 mg / mL and drop it onto the surface of the perovskite layer. Perform dynamic spin coating at 5000 rpm for 30 s without annealing to obtain the second passivation layer with a thickness of 5 nm. S8. A LiF passivation layer with a thickness of 1 nm is deposited by vapor deposition at a rate of 0.05 Å / s. S9. A C60 electron transport layer with a thickness of 30 nm is deposited at a rate of 0.15 Å / s. S10, vapor-deposited Ag electrode, with a thickness of 140nm.

[0072] Example 9 S1 and FTO glass were ultrasonically cleaned for 10 minutes each with dish soap water, ultrapure water and anhydrous ethanol, then dried with N2 air gun and plasma treated for 8 minutes in an oxygen atmosphere. S2. Take a NiOx solution with a concentration of 10 mg / mL and spread it on the surface of the FTO substrate. Spin-coat at 3000 rpm for 30 s and anneal on a hot plate at 150℃ for 10 min to obtain a hole transport layer with a thickness of 20 nm. S3. After the FTO substrate cools to room temperature, transfer it to a glove box filled with nitrogen. Spread an anhydrous ethanol solution of MeO-2PACz (dipole moment ~0.2D) at a concentration of 0.3 mg / mL onto the surface of the hole transport layer. Spin-coat at 3000 rpm for 30 s and anneal on a hot plate at 100℃ for 10 min to obtain the first functional layer. The thickness of the first functional layer is 3 nm and the water contact angle is ~65°. S4. Take an anhydrous ethanol solution of Me-4PACz with a concentration of 0.3 mg / mL (dipole moment of ~1.7D) and spread it on the surface of the first functional layer. Spin-coat at 3000 rpm for 30 s and anneal on a hot plate at 100℃ for 10 min to obtain the second functional layer. The thickness of the second functional layer is 3 nm and the water contact angle is ~85°. S5. Take a 1.1 mg / mL anhydrous ethanol mixture of PEAI and PFN-Br (mass ratio of PEAI and PFN-Br is 10:1) and add it dropwise to the surface of the second functional layer. Perform dynamic spin coating at 5000 rpm for 30 s without annealing to obtain the first passivation layer with a thickness of 5 nm. S6. Take the perovskite precursor solution and spread it on the surface of the first passivation layer. First spin coat it at 2000 rpm for 10 s, then spin coat it at 5000 rpm for 40 s. When spin coating is carried out for 35 s, add 150 μL of the anti-solvent ethyl acetate. Heat the perovskite wet film on a hot stage at 120 ℃ for 20 min. The thickness of the perovskite layer is 650 nm. S7. A LiF passivation layer with a thickness of 1 nm is deposited by vapor deposition at a rate of 0.05 Å / s. S8. A C60 electron transport layer with a thickness of 30 nm is deposited at a rate of 0.15 Å / s. S9, vapor-deposited Ag electrode, with a thickness of 140nm.

[0073] Example 10 S1 and FTO glass were ultrasonically cleaned for 10 minutes each with dish soap water, ultrapure water and anhydrous ethanol, then dried with N2 air gun and plasma treated for 8 minutes in an oxygen atmosphere. S2. Take a NiOx solution with a concentration of 10 mg / mL and spread it on the surface of the FTO substrate. Spin-coat at 3000 rpm for 30 s and anneal on a hot plate at 150℃ for 10 min to obtain a hole transport layer with a thickness of 20 nm. S3. After the FTO substrate cools to room temperature, transfer it to a glove box filled with nitrogen. Spread an anhydrous ethanol solution of MeO-2PACz (dipole moment ~0.2D) at a concentration of 0.3 mg / mL onto the surface of the hole transport layer. Spin-coat at 3000 rpm for 30 s and anneal on a hot plate at 100℃ for 10 min to obtain the first functional layer. The thickness of the first functional layer is 3 nm and the water contact angle is ~65°. S4. Take an anhydrous ethanol solution of Me-4PACz with a concentration of 0.3 mg / mL (dipole moment of ~1.7D) and spread it on the surface of the first functional layer. Spin-coat at 3000 rpm for 30 s and anneal on a hot plate at 100℃ for 10 min to obtain the second functional layer. The thickness of the second functional layer is 3 nm and the water contact angle is ~85°. S5. Take the perovskite precursor solution and spread it on the surface of the second functional layer. First spin coat it at 2000 rpm for 10 s, then spin coat it at 5000 rpm for 40 s. When spin coating is carried out for 35 s, add 150 μL of the anti-solvent ethyl acetate. Heat the perovskite wet film on a hot stage at 120 ℃ for 20 min. The thickness of the perovskite layer is 650 nm. S6. Take a PEAI and MASCN (mass ratio of PEAI and MASCN is 4:1) mixed solution of IPA-DMF (volume ratio of IPA and DMF is 100:1) with a concentration of 1 mg / mL and drop it onto the surface of the perovskite layer. Perform dynamic spin coating at 5000 rpm for 30 s without annealing to obtain the second passivation layer with a thickness of 5 nm. S7. A LiF passivation layer with a thickness of 1 nm is deposited by vapor deposition at a rate of 0.05 Å / s. S8. A C60 electron transport layer with a thickness of 30 nm is deposited at a rate of 0.15 Å / s. S9, vapor-deposited Ag electrode, with a thickness of 140nm.

[0074] Example 11 S1 and FTO glass were ultrasonically cleaned for 10 minutes each with dish soap water, ultrapure water and anhydrous ethanol, then dried with N2 air gun and plasma treated for 8 minutes in an oxygen atmosphere. S2. Take a NiOx solution with a concentration of 10 mg / mL and spread it on the surface of the FTO substrate. Spin-coat at 3000 rpm for 30 s and anneal on a hot plate at 150℃ for 10 min to obtain a hole transport layer with a thickness of 20 nm. S3. After the FTO substrate cools to room temperature, transfer it to a glove box filled with nitrogen. Spread an anhydrous ethanol solution with a concentration of 0.3 mg / mL 2PACz (dipole moment of ~2D) all over the surface of the hole transport layer. Spin coat at 3000 rpm for 30 s and anneal on a hot plate at 100℃ for 10 min to obtain the first functional layer. The thickness of the first functional layer is 3 nm and the water contact angle is ~64°. S4. Take an anhydrous ethanol solution of Me-4PACz with a concentration of 0.3 mg / mL (dipole moment of ~1.7D) and spread it on the surface of the first functional layer. Spin-coat at 3000 rpm for 30 s and anneal on a hot plate at 100℃ for 10 min to obtain the second functional layer. The thickness of the second functional layer is 3 nm and the water contact angle is 85°. S5. Take a 1.1 mg / mL anhydrous ethanol mixture of PEAI and PFN-Br (mass ratio of PEAI and PFN-Br is 10:1) and add it dropwise to the surface of the second functional layer. Perform dynamic spin coating at 5000 rpm for 30 s without annealing to obtain the first passivation layer with a thickness of 5 nm. S6. Take the perovskite precursor solution and spread it on the surface of the first passivation layer. First spin coat it at 2000 rpm for 10 s, then spin coat it at 5000 rpm for 40 s. When spin coating is carried out for 35 s, add 150 μL of the anti-solvent ethyl acetate. Heat the perovskite wet film on a hot stage at 120 ℃ for 20 min. The thickness of the perovskite layer is 650 nm. S7. Take a PEAI and MASCN (mass ratio of PEAI and MASCN is 4:1) mixed solution of IPA-DMF (volume ratio of IPA and DMF is 100:1) with a concentration of 1 mg / mL and drop it onto the surface of the perovskite layer. Perform dynamic spin coating at 5000 rpm for 30 s without annealing to obtain the second passivation layer with a thickness of 5 nm. S8. A LiF passivation layer with a thickness of 1 nm is deposited by vapor deposition at a rate of 0.05 Å / s. S9. A C60 electron transport layer with a thickness of 30 nm is deposited at a rate of 0.15 Å / s. S10, vapor-deposited Ag electrode, with a thickness of 140nm.

[0075] Example 12 S1 and FTO glass were ultrasonically cleaned for 10 minutes each with dish soap water, ultrapure water and anhydrous ethanol, then dried with N2 air gun and plasma treated for 8 minutes in an oxygen atmosphere. S2. Take a NiOx solution with a concentration of 10 mg / mL and spread it on the surface of the FTO substrate. Spin-coat at 3000 rpm for 30 s and anneal on a hot plate at 150℃ for 10 min to obtain a hole transport layer with a thickness of 20 nm. S3. After the FTO substrate cools to room temperature, transfer it to a glove box filled with nitrogen. Spread an anhydrous ethanol solution of MeO-2PACz (dipole moment ~0.2D) at a concentration of 0.3 mg / mL onto the surface of the hole transport layer. Spin-coat at 3000 rpm for 30 s and anneal on a hot plate at 100℃ for 10 min to obtain the first functional layer. The thickness of the first functional layer is 3 nm and the water contact angle is ~65°. S4. Take an anhydrous ethanol solution of Me-4PACz with a concentration of 0.3 mg / mL (dipole moment of ~1.7D) and spread it on the surface of the first functional layer. Spin-coat at 3000 rpm for 30 s and anneal on a hot plate at 100℃ for 10 min to obtain the second functional layer. The thickness of the second functional layer is 3 nm and the water contact angle is ~85°. S5. Take a 1.1 mg / mL anhydrous ethanol mixture of PEAI and PFN-Br (mass ratio of PEAI and PFN-Br is 5:1) and drop it onto the surface of the second functional layer. Perform dynamic spin coating at 5000 rpm for 30 s without annealing to obtain the first passivation layer with a thickness of 5 nm. S6. Take the perovskite precursor solution and spread it on the surface of the first passivation layer. First spin coat it at 2000 rpm for 10 s, then spin coat it at 5000 rpm for 40 s. When spin coating is carried out for 35 s, add 150 μL of the anti-solvent ethyl acetate. Heat the perovskite wet film on a hot stage at 120 ℃ for 20 min. The thickness of the perovskite layer is 650 nm. S7. Take a PEAI and MASCN (mass ratio of PEAI and MASCN is 4:1) mixed solution of IPA-DMF (volume ratio of IPA and DMF is 100:1) with a concentration of 1 mg / mL and drop it onto the surface of the perovskite layer. Perform dynamic spin coating at 5000 rpm for 30 s without annealing to obtain the second passivation layer with a thickness of 5 nm. S8. A LiF passivation layer with a thickness of 1 nm is deposited by vapor deposition at a rate of 0.05 Å / s. S9. A C60 electron transport layer with a thickness of 30 nm is deposited at a rate of 0.15 Å / s. S10, vapor-deposited Ag electrode, with a thickness of 140nm.

[0076] Example 13 S1 and FTO glass were ultrasonically cleaned for 10 minutes each with dish soap water, ultrapure water and anhydrous ethanol, then dried with N2 air gun and plasma treated for 8 minutes in an oxygen atmosphere. S2. Take a NiOx solution with a concentration of 10 mg / mL and spread it on the surface of the FTO substrate. Spin-coat at 3000 rpm for 30 s and anneal on a hot plate at 150℃ for 10 min to obtain a hole transport layer with a thickness of 20 nm. S3. After the FTO substrate cools to room temperature, transfer it to a glove box filled with nitrogen. Spread an anhydrous ethanol solution of MeO-2PACz (dipole moment ~0.2D) at a concentration of 0.3 mg / mL onto the surface of the hole transport layer. Spin-coat at 3000 rpm for 30 s and anneal on a hot plate at 100℃ for 10 min to obtain the first functional layer. The thickness of the first functional layer is 3 nm and the water contact angle is ~65°. S4. Take an anhydrous ethanol solution of Me-4PACz with a concentration of 0.3 mg / mL (dipole moment of ~1.7D) and spread it on the surface of the first functional layer. Spin-coat at 3000 rpm for 30 s and anneal on a hot plate at 100℃ for 10 min to obtain the second functional layer. The thickness of the second functional layer is 3 nm and the water contact angle is ~85°. S5. Take a 1.1 mg / mL anhydrous ethanol mixture of PEAI and PFN-Br (mass ratio of PEAI and PFN-Br is 10:1) and add it dropwise to the surface of the second functional layer. Perform dynamic spin coating at 5000 rpm for 30 s without annealing to obtain the first passivation layer with a thickness of 5 nm. S6. Take the perovskite precursor solution and spread it on the surface of the first passivation layer. First spin coat it at 2000 rpm for 10 s, then spin coat it at 5000 rpm for 40 s. When spin coating is carried out for 35 s, add 150 μL of the anti-solvent ethyl acetate. Heat the perovskite wet film on a hot stage at 120 ℃ for 20 min. The thickness of the perovskite layer is 650 nm. S7. Take a 1 mg / mL IPA-DMF mixed solution of PEAI and MASCN (mass ratio of PEAI and MASCN is 1:1) (volume ratio of IPA and DMF is 100:1) and drop it onto the surface of the perovskite layer. Perform dynamic spin coating at 5000 rpm for 30 s without annealing to obtain a second passivation layer with a thickness of 5 nm. S8. A LiF passivation layer with a thickness of 1 nm is deposited by vapor deposition at a rate of 0.05 Å / s. S9. A C60 electron transport layer with a thickness of 30 nm is deposited at a rate of 0.15 Å / s. S10, vapor-deposited Ag electrode, with a thickness of 140nm.

[0077] Example 14 S1 and FTO glass were ultrasonically cleaned for 10 minutes each with dish soap water, ultrapure water and anhydrous ethanol, then dried with N2 air gun and plasma treated for 8 minutes in an oxygen atmosphere. S2. Take a NiOx solution with a concentration of 10 mg / mL and spread it on the surface of the FTO substrate. Spin-coat at 3000 rpm for 30 s and anneal on a hot plate at 150℃ for 10 min to obtain a hole transport layer with a thickness of 20 nm. S3. After the FTO substrate cools to room temperature, transfer it to a glove box filled with nitrogen. Spread an anhydrous ethanol solution of MeO-2PACz (dipole moment ~0.2D) at a concentration of 0.1 mg / mL onto the surface of the hole transport layer. Spin-coat at 3000 rpm for 30 s and anneal on a hot plate at 100℃ for 10 min to obtain the first functional layer. The thickness of the first functional layer is 1 nm and the water contact angle is ~65°. S4. Take an anhydrous ethanol solution of Me-4PACz with a concentration of 0.1 mg / mL (dipole moment of ~1.7D) and spread it on the surface of the first functional layer. Spin-coat at 3000 rpm for 30 s and anneal on a hot plate at 100℃ for 10 min to obtain the second functional layer. The thickness of the second functional layer is 1 nm and the water contact angle is ~85°. S5. Take the perovskite precursor solution and spread it on the surface of the second functional layer. First spin coat it at 2000 rpm for 10 s, then spin coat it at 5000 rpm for 40 s. When spin coating is carried out for 35 s, add 150 μL of the anti-solvent ethyl acetate. Heat the perovskite wet film on a hot stage at 120 ℃ for 20 min. The thickness of the perovskite layer is 650 nm. S6. A LiF passivation layer with a thickness of 1 nm is deposited by vapor deposition at a rate of 0.05 Å / s. S7. A C60 electron transport layer with a thickness of 30 nm is deposited at a rate of 0.15 Å / s. S8, vapor-deposited Ag electrode, with a thickness of 140nm.

[0078] Example 15 S1 and FTO glass were ultrasonically cleaned for 10 minutes each with dish soap water, ultrapure water and anhydrous ethanol, then dried with N2 air gun and plasma treated for 8 minutes in an oxygen atmosphere. S2. Take a NiOx solution with a concentration of 10 mg / mL and spread it on the surface of the FTO substrate. Spin-coat at 3000 rpm for 30 s and anneal on a hot plate at 150℃ for 10 min to obtain a hole transport layer with a thickness of 20 nm. S3. After the FTO substrate cools to room temperature, transfer it to a glove box filled with nitrogen. Spread an anhydrous ethanol solution of MeO-2PACz (dipole moment ~0.2D) at a concentration of 0.3 mg / mL onto the surface of the hole transport layer. Spin-coat at 3000 rpm for 30 s and anneal on a hot plate at 100℃ for 10 min to obtain the first functional layer. The thickness of the first functional layer is 3 nm and the water contact angle is ~65°. S4. Take an anhydrous ethanol solution of Me-4PACz with a concentration of 0.3 mg / mL (dipole moment of ~1.7D) and spread it on the surface of the first functional layer. Spin-coat at 3000 rpm for 30 s and anneal on a hot plate at 100℃ for 10 min to obtain the second functional layer. The thickness of the second functional layer is 3 nm and the water contact angle is ~85°. S5. Take a PEAI anhydrous ethanol mixed solution with a concentration of 1 mg / mL and drop it onto the surface of the second functional layer. Perform dynamic spin coating at a speed of 5000 rpm for 30 seconds. No annealing is required to obtain the first passivation layer with a thickness of 5 nm. S6. Take the perovskite precursor solution and spread it on the surface of the first passivation layer. First spin coat it at 2000 rpm for 10 s, then spin coat it at 5000 rpm for 40 s. When spin coating is carried out for 35 s, add 150 μL of the anti-solvent ethyl acetate. Heat the perovskite wet film on a hot stage at 120 ℃ for 20 min. The thickness of the perovskite layer is 650 nm. S7. Take a PEAI IPA-DMF solution with a concentration of 1 mg / mL (IPA and DMF volume ratio of 100:1) and drop it onto the surface of the perovskite layer. Perform dynamic spin coating at a speed of 5000 rpm for 30 seconds. No annealing is required to obtain the second passivation layer with a thickness of 5 nm. S8. A LiF passivation layer with a thickness of 1 nm is deposited by vapor deposition at a rate of 0.05 Å / s. S9. A C60 electron transport layer with a thickness of 30 nm is deposited at a rate of 0.15 Å / s. S10, vapor-deposited Ag electrode, with a thickness of 140nm.

[0079] Comparative Example 1 S1 and FTO glass were ultrasonically cleaned for 10 minutes each with dish soap water, ultrapure water and anhydrous ethanol, then dried with N2 air gun and plasma treated for 8 minutes in an oxygen atmosphere. S2. Transfer the FTO glass to a glove box filled with nitrogen. Spread an anhydrous ethanol solution of mixed self-assembled molecules (MeO-2PACz and Me-4PACz in a mass ratio of 3:1) at a concentration of 0.3 mg / mL onto the surface of the FTO glass substrate. Spin-coat at 3000 rpm for 30 s and anneal on a hot plate at 100 °C for 10 min to obtain the functional layer. The thickness of the functional layer is 3 nm and the contact angle is ~67°. S3. Spread the perovskite precursor solution all over the surface of the functional layer. First spin coat at 2000 rpm for 10 s, then spin coat at 5000 rpm for 40 s. When spin coating reaches 35 s, add 150 μL of the antisolvent ethyl acetate. Heat the perovskite wet film on a hot stage at 120 ℃ for 20 min. The thickness of the perovskite layer is 650 nm. S4. A LiF passivation layer with a thickness of 1 nm is deposited by vapor deposition at a rate of 0.05 Å / s. S5. A C60 electron transport layer with a thickness of 30 nm is deposited at a rate of 0.15 Å / s. S6, vapor-deposited Ag electrode with a thickness of 140nm.

[0080] Comparative Example 2 S1 and FTO glass were ultrasonically cleaned for 10 minutes each with dish soap water, ultrapure water and anhydrous ethanol, then dried with N2 air gun and plasma treated for 8 minutes in an oxygen atmosphere. S2. Take a NiOx solution with a concentration of 10 mg / mL and spread it on the surface of the FTO substrate. Spin-coat at 3000 rpm for 30 s and anneal on a hot plate at 150℃ for 10 min to obtain a hole transport layer with a thickness of 20 nm. S3. After the FTO substrate cools to room temperature, transfer it to a glove box filled with nitrogen. Spread an anhydrous ethanol solution of mixed self-assembled molecules (MeO-2PACz and Me-4PACz in a mass ratio of 3:1) at a concentration of 0.3 mg / mL onto the surface of the hole transport layer. Spin-coat at 3000 rpm for 30 s and anneal on a hot plate at 100 °C for 10 min to obtain the functional layer. The thickness of the functional layer is 3 nm and the contact angle is ~67°. S4. Spread the perovskite precursor solution all over the surface of the functional layer. First spin coat at 2000 rpm for 10 s, then spin coat at 5000 rpm for 40 s. When spin coating reaches 35 s, add 150 μL of the antisolvent ethyl acetate. Heat the perovskite wet film on a hot stage at 120 ℃ for 20 min. The thickness of the perovskite layer is 650 nm. S5. A LiF passivation layer with a thickness of 1 nm is deposited by vapor deposition at a rate of 0.05 Å / s. S6. A C60 electron transport layer with a thickness of 30 nm is deposited at a rate of 0.15 Å / s. S7, vapor-deposited Ag electrode, with a thickness of 140nm.

[0081] Comparative Example 3 S1 and FTO glass were ultrasonically cleaned for 10 minutes each with dish soap water, ultrapure water and anhydrous ethanol, then dried with N2 air gun and plasma treated for 8 minutes in an oxygen atmosphere. S2. Take a NiOx solution with a concentration of 10 mg / mL and spread it on the surface of the FTO substrate. Spin-coat at 3000 rpm for 30 s and anneal on a hot plate at 150℃ for 10 min to obtain a hole transport layer with a thickness of 20 nm. S3. After the FTO substrate cools to room temperature, transfer it to a glove box filled with nitrogen. Spread an anhydrous ethanol solution of Me-4PACz (dipole moment ~1.7D) at a concentration of 0.3 mg / mL onto the surface of the hole transport layer. Spin-coat at 3000 rpm for 30 s and anneal on a hot plate at 100℃ for 10 min to obtain the functional layer. The thickness of the functional layer is 3 nm and the contact angle is ~85°. S4. Spread the perovskite precursor solution all over the surface of the functional layer. First spin coat at 2000 rpm for 10 s, then spin coat at 5000 rpm for 40 s. When spin coating reaches 35 s, add 150 μL of the antisolvent ethyl acetate. Heat the perovskite wet film on a hot stage at 120 ℃ for 20 min. The thickness of the perovskite layer is 650 nm. S6. A LiF passivation layer with a thickness of 1 nm is deposited by vapor deposition at a rate of 0.05 Å / s. S7. A C60 electron transport layer with a thickness of 30 nm is deposited at a rate of 0.15 Å / s. S8, vapor-deposited Ag electrode, with a thickness of 140nm.

[0082] Performance testing (1) Current density-voltage characteristic curve (JV) test The device was placed inside the test box, and the effective area of ​​the solar cell was 0.16 cm² during testing. 2 Measurements were taken using a voltage source meter under an AM 1.5G solar simulator, with an irradiance of 100 mW / cm².2 .

[0083] The test results are shown in Table 1 and Figure 2 As shown.

[0084] (2) Electrochemical impedance spectroscopy test Electrochemical impedance spectroscopy (EIS) studies the relationship between AC impedance and frequency during electrochemical processes when the battery is in equilibrium (open circuit) or under stable DC polarization conditions, with a small AC excitation signal applied according to a sinusoidal law. A higher recombination resistance indicates suppressed non-radiative recombination, and correspondingly, a higher open-circuit voltage (Voc) of the battery.

[0085] Equivalent circuit model (bias voltage: 0.9V, frequency: 10) 6 Hz, voltage disturbance: 30mV) Figure 3 As shown, R1 represents the system series resistance, and Rre represents the composite resistance.

[0086] Test results are as follows Figure 4 As shown.

[0087] Table 1

[0088] The test results above show that by introducing a first functional layer and a second functional layer, which include self-assembled molecules, the energy level matching between the hole transport layer and the perovskite layer is adjusted, the interfacial recombination loss is reduced, and the battery performance is improved.

[0089] The above description represents the preferred embodiments of this application, but should not be construed as limiting the scope of this application. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of this application, and these improvements and modifications are also considered to be within the scope of protection of this application.

Claims

1. A perovskite solar cell, characterized in that, The perovskite solar cell comprises a hole transport layer, a functional layer, and a perovskite layer stacked sequentially. The functional layer includes a first functional layer and a second functional layer; The first functional layer and the second functional layer each independently include self-assembling molecules.

2. The perovskite solar cell as described in claim 1, characterized in that, The perovskite solar cell includes a hole transport layer, a first functional layer, a second functional layer and a perovskite layer stacked sequentially. The first functional layer includes a first self-assembled molecule and the second functional layer includes a second self-assembled molecule. The surface wettability of the first functional layer is greater than that of the second functional layer; And / or, the dipole moment of the second self-assembled molecule is greater than the dipole moment of the first self-assembled molecule.

3. The perovskite solar cell as described in claim 2, characterized in that, The contact angle of the first functional layer is less than or equal to 65°, and the contact angle of the second functional layer is greater than or equal to 70°. And / or, the dipole moment of the second self-assembled molecule is greater than or equal to 1.5D, and the dipole moment of the first self-assembled molecule is less than or equal to 1.0D.

4. The perovskite solar cell as described in claim 2 or 3, characterized in that, The first self-assembled molecule includes MeO-2PACz and / or 2PACz; And / or, the second self-assembled molecule includes one or more of Me-4PACz, Ph-4PACz, 4PADCB, MeO-4PADCB and DMAcPA.

5. The perovskite solar cell as described in claim 4, characterized in that, The first self-assembled molecule is MeO-2PACz, and the second self-assembled molecule is Me-4PACz.

6. The perovskite solar cell according to claim 1, characterized in that, The thickness of the first functional layer is 3-5 nm, and / or the thickness of the second functional layer is 3-5 nm.

7. The perovskite solar cell according to claim 1, characterized in that, The perovskite solar cell further includes a first passivation layer disposed between the functional layer and the perovskite layer, the first passivation layer comprising PFN-Br.

8. The perovskite solar cell as described in claim 5, characterized in that, The first passivation layer further includes PEAI, wherein the mass ratio of PEAI to PFN-Br is (8-10):1; And / or, the thickness of the first passivation layer is 5-10 nm.

9. The perovskite solar cell according to claim 1, characterized in that, The perovskite solar cell further includes a second passivation layer disposed on the surface of the perovskite layer away from the functional layer, and the second passivation layer includes methyl ammonium thiocyanate.

10. The perovskite solar cell according to claim 7, characterized in that, The second passivation layer also includes PEAI, wherein the mass ratio of PEAI to ammonium thiocyanate is (2-5):1; And / or, the thickness of the second passivation layer is 5-10 nm.

11. The perovskite solar cell according to claim 1, characterized in that, The hole transport layer comprises NiOx, and / or the thickness of the hole transport layer is 10-20 nm.

12. The perovskite solar cell according to any one of claims 1-9, characterized in that, The perovskite solar cell further includes a transparent conductive substrate located on the surface of the hole transport layer away from the perovskite layer.

13. The perovskite solar cell as described in claim 10, characterized in that, The perovskite solar cell includes, from bottom to top, the transparent conductive substrate, the hole transport layer, the first functional layer, the second functional layer, the first passivation layer, the perovskite layer, the second passivation layer, the electron transport layer, the hole blocking layer, and the metal electrode, which are stacked sequentially.

14. A method for preparing a perovskite solar cell according to any one of claims 1-11, characterized in that, Includes the following steps: S1. Coat the surface of the hole transport layer with a first self-assembled molecular alcohol solution and perform a first annealing treatment to obtain a first functional layer. S2. Coat the surface of the first functional layer with a second self-assembled molecular alcohol solution and perform a second annealing treatment to obtain the second functional layer. S3. Prepare a perovskite layer on the surface of the second functional layer.

15. The method for preparing a perovskite solar cell as described in claim 12, characterized in that, The concentration of the first self-assembled molecule in the alcoholic solution of the first self-assembled molecule is 0.3-0.5 mg / mL, and / or the first self-assembled molecule includes MeO-2PACz and / or 2PACz; And / or, the concentration of the second self-assembled molecule in the alcoholic solution of the second self-assembled molecule is 0.3-0.5 mg / mL, and / or, the second self-assembled molecule includes one or more of Me-4PACz, Ph-4PACz, 4PADCB, MeO-4PADCB and DMAcPA.

16. The method for preparing a perovskite solar cell according to claim 12, characterized in that, In step S1, the coating is performed by spin coating at a speed of 2000-5000 rpm for 20-40 seconds. And / or, the temperature of the first annealing treatment is 100-110℃, and the time of the first annealing treatment is 5-15 min.

17. The method for preparing a perovskite solar cell according to claim 12, characterized in that, In step S2, the coating is performed by spin coating at a speed of 2000-5000 rpm for 20-40 seconds. And / or, the temperature of the second annealing treatment is 100-110℃, and the time of the second annealing treatment is 5-15 min.

18. The method for preparing a perovskite solar cell as described in claim 12, characterized in that, It also includes the preparation of a first passivation layer: coating the surface of the second functional layer with a first mixed solution to obtain the first passivation layer; the first mixed solution includes PFN-Br.

19. The method for preparing a perovskite solar cell as described in claim 14, characterized in that, The first mixed solution comprises PEAI and PFN-Br, wherein the mass ratio of PEAI to PFN-Br is (8-10):

1.

20. The method for preparing a perovskite solar cell according to claim 12, characterized in that, It also includes the preparation of a second passivation layer: coating the surface of the perovskite layer with a second mixed solution to obtain the second passivation layer; the second mixed solution includes methyl ammonium thiocyanate.

21. The method for preparing a perovskite solar cell according to claim 12, characterized in that, The second mixed solution comprises PEAI and methyl ammonium thiocyanate, wherein the mass ratio of PEAI to methyl ammonium thiocyanate is (2-5):

1.

22. A solar cell module, characterized in that, The solar cell module includes the perovskite solar cell according to any one of claims 1-11.

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