Perovskite crystalline silicon tandem cell and preparation method thereof, photovoltaic module and photovoltaic system

Abstract

The embodiment of the present application discloses a perovskite crystalline silicon laminated cell, a preparation method thereof, a photovoltaic module and a photovoltaic system. The perovskite crystalline silicon laminated cell comprises a crystalline silicon bottom cell, an intermediate composite layer, a hole transport layer, a perovskite light absorption layer, an electron transport layer and an electrode layer which are sequentially stacked. The surface of the intermediate composite layer adjacent to the hole transport layer is a rough surface structure. The material of the hole transport layer comprises self-assembled monolayer material and borate-containing surfactant. The present application introduces borate-containing surfactant into the self-assembled monolayer hole transport layer of the perovskite crystalline silicon laminated cell, and systematically solves the key contradiction between interface uniformity and device performance and stability.

Description

Technical Field

[0001] This invention relates to the field of photovoltaic cell technology, and more specifically, to a perovskite-silicon tandem cell and its preparation method, as well as photovoltaic modules and photovoltaic systems. Background Technology

[0002] Perovskite-silicon tandem solar cells, as a promising emerging photovoltaic technology, have achieved significant breakthroughs in photoelectric conversion efficiency in recent years. In their device structure, self-assembled monolayer materials, due to their excellent interfacial energy level modulation capabilities and process compatibility, have become a key component for realizing high-efficiency devices. However, these molecules, driven by strong intermolecular interactions and solvent effects during solution deposition, tend to aggregate and form micelles, leading to uneven coverage on the substrate, the formation of nanoscale pores, and high-resistance pathways. Furthermore, for organic-inorganic hybrid perovskites, the spatial distribution of A-site cations differs greatly, with inorganic A-site ions (Cs) exhibiting significantly different spatial distributions. + They tend to accumulate at the bottom of the perovskite light-absorbing layer, while organic ions (MA) tend to accumulate there. + / FA + The phases tend to accumulate on top of the perovskite light-absorbing layer. When viewed vertically from the cross-section of the perovskite light-absorbing layer, the spatial distribution of the perovskite phases is non-uniform, and this non-uniformity severely affects the efficiency of the device.

[0003] CN115458691A discloses a method for controlling the uniformity of perovskite thin film composition and a perovskite solar cell. By adding at least one of thiophene, selenophene, thiophene derivative organic molecules, and selenophene derivative organic molecules as additives to the perovskite precursor solution, the uniformity of perovskite thin film composition distribution is significantly improved, thereby enhancing the photoelectric conversion efficiency and operational stability of the solar cell. However, this method requires strict control of the additive dosage and is costly.

[0004] CN122094294A discloses a molecularly co-doped hole transport layer and its preparation method, as well as an inverted perovskite solar cell. By introducing O-phosphate-L-tyrosine (OPLt) into the Me-4PACz system, the OPLt molecules suppress the π-π stacking between Me-4PACz molecules, reduce the accumulation of interfacial charge, alleviate the aggregation tendency of Me-4PACz molecules, and guide them to form a uniform and dense self-assembled layer on the substrate surface, thereby suppressing the generation of interfacial voids and improving the morphology quality of the film layer. However, this invention has a single effect and cannot simultaneously improve the problem of uneven composition in the vertical direction of the perovskite light-absorbing layer.

[0005] CN121692963A discloses a high-efficiency and stable inverse perovskite solar cell based on the improved mechanical strength of a self-assembled monolayer and its fabrication method. This involves depositing 3,3'-(2,7-dibromo-9H-fluorene-9,9-diyl)bis(N,N-dimethylpropyl-1-amine) (FN-Br) on a conventional self-assembled monolayer Me-4PACz. The planar fluorene framework of FN-Br and the carbazole units of Me-4PACz generate strong π-π stacking, constructing a robust intermolecular network and increasing its Young's modulus by more than two times. However, this invention only suppresses molecular aggregation and undesirable conformational changes in the hole transport layer Me-4PACz under thermal stress, and cannot improve the problem of uneven composition distribution in the vertical direction of the perovskite light-absorbing layer.

[0006] Therefore, providing a technical solution that not only improves the problem of easy aggregation of self-assembled monomolecules, but also enables uniform distribution of A-site ions in the vertical direction of the perovskite light-absorbing layer is of great significance for improving the hole extraction capability of self-assembled molecules and the quality of the perovskite light-absorbing layer. Summary of the Invention

[0007] This invention provides a perovskite-silicon tandem solar cell, its fabrication method, photovoltaic module, and photovoltaic system. The perovskite-silicon tandem solar cell provided by this invention introduces boric acid surfactants with structures of Formulas 1 to 3 into the hole transport layer of the self-assembled single-molecule material, systematically solving the key contradiction between interface uniformity and device performance and stability.

[0008] In a first aspect, a perovskite-silicon tandem solar cell is provided, comprising a crystalline silicon base cell, an intermediate composite layer, a hole transport layer, a perovskite light-absorbing layer, an electron transport layer, and an electrode layer stacked sequentially; the perovskite light-absorbing layer is made of ABX3 perovskite material; the surface of the intermediate composite layer adjacent to the hole transport layer has a textured structure; the hole transport layer is made of a self-assembled monomolecular material and a boric acid surfactant; the boric acid surfactant includes a boric acid compound, which includes boric acid groups and passivating groups, the boric acid groups are anchored to the intermediate composite layer, and the passivating groups are hydrogen-bonded to the A-site cations of the perovskite material in the perovskite light-absorbing layer.

[0009] The perovskite-silicon tandem solar cell provided by this invention introduces a boric acid-containing surfactant into the hole transport layer of the self-assembled monolayer material. One end of the boric acid group of the boric acid compound can be anchored to the textured surface of a transparent conductive oxide. The benzene ring and pyridine structure contained in the middle of the molecule can enhance the molecular dipole moment, thereby solving the problem of easy aggregation of the self-assembled monolayer and improving the hole extraction capability of the self-assembled molecules. The passivation group at the other end can also interact with the A-site organic cation (FA) in the perovskite material. + / MA+ Strong hydrogen bonds are formed between the perovskite light-absorbing layer and the perovskite light-absorbing layer, resulting in a uniform distribution of A-site ions in the vertical direction. This improves the quality of the perovskite light-absorbing layer and the device efficiency, and systematically solves the key contradiction between interface uniformity and device performance and stability.

[0010] Preferably, the boric acid surfactant has any one or a combination of at least two of the boric acid compounds shown in Formulas 1 to 3, wherein in Formulas 1 to 3, R includes any one of amino, carboxyl, or hydroxyl groups, and n is an integer from 0 to 4. The structures of Formulas 1 to 3 are shown in the following figure: ; ; .

[0011] In some embodiments, the boric acid compound includes any one or a combination of at least two of 4-hydroxymethylphenylboronic acid, 4-aminomethylphenylboronic acid, 4-carboxyphenylboronic acid, 4-(3-hydroxypropyl)phenylboronic acid, 6-(hydroxymethyl)pyridin-3-boronic acid, or (5-(hydroxymethyl)pyridin-2-yl)boronic acid.

[0012] In some embodiments, the mass ratio of boric acid surfactant to self-assembled monomolecule material in the hole transport layer is (0.1~0.5):1.

[0013] In some embodiments, the self-assembled monomolecular material package includes any one or a combination of at least two of 2PACz, 4PACz, derivatives of 2PACz, or derivatives of 4PACz.

[0014] In some embodiments, the perovskite light-absorbing layer is made of ABX3 perovskite material, wherein A is CH3NH3. + CH(NH2)2 + Cs + or Rb + B is any combination of one or at least two of the following, where B is Pb. 2+ Sn 2+ Or Ge 2+ Any combination of one or at least two of them, X is Cl - ,Br - Or I - Any one or at least two of them.

[0015] In some embodiments, the material of the intermediate composite layer includes any one of ITO, IZO, or tin oxide.

[0016] In some embodiments, the thickness of the intermediate composite layer is 5 nm to 20 nm.

[0017] In some embodiments, the thickness of the hole transport layer is 1 nm to 3 nm.

[0018] In some embodiments, the thickness of the perovskite light-absorbing layer is 400 nm to 600 nm.

[0019] In a second aspect, the present invention provides a method for preparing a perovskite-silicon tandem solar cell as described in the first aspect, the method comprising: An intermediate composite layer is prepared on the surface of an N-type silicon substrate of a crystalline silicon bottom cell; a hole transport layer solution is spin-coated on the surface of the intermediate composite layer and annealed to obtain a hole transport layer; a perovskite light-absorbing layer, an electron transport layer and an electrode layer are sequentially prepared on the surface of the hole transport layer to obtain the perovskite crystalline silicon tandem cell. The hole transport layer solution includes self-assembled monomolecule materials and boric acid-containing surfactants.

[0020] In some embodiments, the concentration of the self-assembled monomolecule material in the hole transport layer solution is 0.5 mg / mL to 1.5 mg / mL.

[0021] In some embodiments, the concentration ratio of boric acid surfactant to self-assembled monomolecule material in the hole transport layer solution is (0.1~0.5):1.

[0022] In some embodiments, the spin coating speed is 2500 rpm to 3500 rpm, and the spin coating time is 20 s to 40 s.

[0023] In some embodiments, the annealing temperature is 90°C to 110°C, and the annealing time is 8 min to 12 min.

[0024] Thirdly, the present invention provides a photovoltaic module, the photovoltaic module comprising the perovskite-silicon tandem cell as described in the first aspect.

[0025] Fourthly, the present invention provides a photovoltaic system comprising the photovoltaic modules as described in the third aspect. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the photovoltaic system provided by the present invention.

[0027] Figure 2 This is a schematic diagram of a photovoltaic module provided by the present invention.

[0028] Figure 3 This is an exploded view of the photovoltaic module provided by the present invention.

[0029] Figure 4 This is a schematic diagram of the hole transport layer structure of the perovskite-silicon tandem solar cell provided in Example 1.

[0030] Figure 5 This is a SEM image of the perovskite light-absorbing layer in Example 1.

[0031] Figure 6 This is a fluorescence lifetime scanning image of the perovskite light-absorbing layer in Example 1.

[0032] Figure 7 This is a contact angle test diagram of the thin film layer prepared by the hole transport layer solution in Example 1.

[0033] Figure 8 This is a schematic diagram of the hole transport layer structure of the perovskite-silicon tandem solar cell provided in Comparative Example 1.

[0034] Figure 9 This is a SEM image of the perovskite light-absorbing layer in Comparative Example 1.

[0035] Figure 10 This is a fluorescence lifetime scan of the perovskite absorber layer in Comparative Example 1.

[0036] Figure 11 This is a contact angle test diagram of the thin film layer prepared by the hole transport layer solution in Comparative Example 1.

[0037] Figure 12 These are the JV curves of the perovskite-silicon tandem solar cells provided in Example 1 and Comparative Example 1.

[0038] The accompanying drawings are not drawn to scale.

[0039] Figure label: 1000 - Photovoltaic system; 100 - Photovoltaic module; 110 - Frame; 120 - Front cover plate; 130 - First encapsulating film; 140 - Cell string layer; 1411 - Crystalline silicon bottom cell; 1412 - Intermediate composite layer; 1413a - Self-assembled monomolecular material; 1413b - Boric acid surfactant; 150 - Second encapsulating film; 160 - Back cover plate; 170 - Junction box. Detailed Implementation

[0040] The descriptions of specific structures or functions implemented according to the inventive concept disclosed in this specification are merely illustrative examples for explaining embodiments of the inventive concept. Those skilled in the art will understand that embodiments of the inventive concept can have various variations and forms, and are not limited to the embodiments described in this specification, but also include various modifications, equivalents, or substitutions made within the scope of the inventive purpose, concept, and technology.

[0041] In the description of this invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the relative orientation or position between different components, are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0042] Although the terms "first" or "second" may be used to describe various components or components, the components or components should not be limited by the terms. The terms above are used only to distinguish one component or component from another. For example, without departing from the scope of the invention, a first battery cell may be referred to as a second battery cell, and similarly, a second battery cell may be referred to as a first battery cell.

[0043] In this invention, unless otherwise explicitly specified and limited, the terms "connected," "fixed," "set," etc., should be interpreted broadly. For example, when one component is said to "connect" another component, it should be understood that it can be directly or indirectly connected to the other component, meaning that other components may also be present in between. Similarly, the terms "fixed" and "set" should be interpreted broadly in a similar manner. Furthermore, the term "connected" can refer to a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can refer to the internal connection of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances. In this invention, unless otherwise explicitly specified and limited, the description of "above" or "below" the second feature (e.g., the first feature is in direct contact with the second feature) or indirectly through an intermediate medium. Moreover, "above," "on top of," and "over" the second feature can mean the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. The first feature being "below", "under", or "below" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0044] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0045] The researchers have discovered that in traditional technologies, perovskite-silicon tandem solar cells typically require an intermediate composite layer to connect the crystalline silicon base cell and the perovskite top cell. Since the surface of the crystalline silicon substrate of the base cell is usually textured, the resulting intermediate composite layer also typically has a textured structure. When the hole transport layer is made of a self-assembled monomolecule, the self-assembled monomolecule is prone to aggregation during fabrication on the textured surface, leading to interface defects. Furthermore, for organic-inorganic hybrid perovskites, the spatial distribution of A-site cations differs significantly, with inorganic A-site ions (Cs) exhibiting different spatial distributions. + They tend to accumulate at the bottom of the perovskite light-absorbing layer, while organic ions (MA) tend to accumulate there. + / FA + The phases tend to accumulate on top of the perovskite light-absorbing layer. When viewed vertically from the cross-section of the perovskite light-absorbing layer, the spatial distribution of the perovskite phases is non-uniform, and this non-uniformity severely affects the efficiency of the device.

[0046] Therefore, solving the problem of easy aggregation of self-assembled monolayers and promoting the uniform distribution of A-site ions in the vertical direction of the perovskite light-absorbing layer are of great significance for improving the hole extraction capability of self-assembled molecules, the quality of the perovskite light-absorbing layer, and the device efficiency.

[0047] Based on this, according to some embodiments of the present invention, the present invention provides a perovskite-silicon tandem solar cell, the perovskite-silicon tandem solar cell comprising a crystalline silicon base cell, an intermediate composite layer, a hole transport layer, a perovskite light-absorbing layer, an electron transport layer, and an electrode layer stacked sequentially; the perovskite light-absorbing layer is made of ABX3 perovskite material; the surface of the intermediate composite layer adjacent to the hole transport layer has a textured structure; the hole transport layer is made of a self-assembled monomolecular material and a boric acid surfactant; the boric acid surfactant includes a boric acid compound, the boric acid compound includes boric acid groups and passivating groups, the boric acid groups are anchored to the intermediate composite layer, and the passivating groups are coupled with A-site cations of the perovskite material in the perovskite light-absorbing layer via hydrogen bonds.

[0048] The perovskite-silicon tandem solar cell provided by this invention introduces a boric acid-containing surfactant into the hole transport layer of the self-assembled monolayer material. One end of the boric acid group of the boric acid compound can be anchored to the textured surface of a transparent conductive oxide. The benzene ring and pyridine structure contained in the middle of the molecule can enhance the molecular dipole moment, thereby solving the problem of easy aggregation of the self-assembled monolayer and improving the hole extraction capability of the self-assembled molecules. The passivation group at the other end can also interact with the A-site organic cation (FA) of the perovskite material. + / MA +Strong hydrogen bonds are formed between the perovskite light-absorbing layer and the perovskite light-absorbing layer, resulting in a uniform distribution of A-site ions in the vertical direction. This improves the quality of the perovskite light-absorbing layer and the device efficiency, and systematically solves the key contradiction between interface uniformity and device performance and stability.

[0049] In some embodiments, the boric acid surfactant comprises any one or a combination of at least two of the boric acid compounds shown in Formulas 1 to 3, wherein R in Formulas 1 to 3 comprises any one of amino, carboxyl, or hydroxyl groups, and n is an integer from 0 to 4. The structures of Formulas 1 to 3 are shown in the following figures: ; ; .

[0050] In some embodiments, the boric acid compound includes any one or a combination of at least two of 4-hydroxymethylphenylboronic acid, 4-aminomethylphenylboronic acid, 4-carboxyphenylboronic acid, 4-(3-hydroxypropyl)phenylboronic acid, 6-(hydroxymethyl)pyridin-3-boronic acid, or (5-(hydroxymethyl)pyridin-2-yl)boronic acid.

[0051] In some embodiments, the mass ratio of boric acid surfactant to self-assembled monomolecule material in the hole transport layer is (0.1~0.5):1, for example, it can be 0.1:1, 0.2:1, 0.25:1, 0.3:1, 0.35:1, 0.4:1, 0.45:1 or 0.5:1.

[0052] In some embodiments, the self-assembled monomolecular material includes any one or a combination of at least two of 2PACz ([2-(9H-carbazole-9-yl)ethyl]phosphonic acid), 4PACz ([4-(9H-carbazole-9-yl)ethyl]phosphonic acid), derivatives of 2PACz, or derivatives of 4PACz.

[0053] In this invention, the derivatives of 2PACz can be, for example, any one or a combination of at least two of Me-2PACz (3,6-dimethyl-2PACz), MeO-2PACz (3,6-dimethoxy-2PACz), MeS-2PACz (3,6-dimethylthio-2PACz), or Br-2PACz (3,6-dibromo-2PACz); the derivatives of 4PACz can be, for example, any one or a combination of at least two of Me-4PACz (3,6-dimethyl-4PACz), MeO-4PACz (3,6-dimethoxy-4PACz), F-4PACz (3,6-difluoro-4PACz), or Br-4PACz (3,6-dibromo-4PACz).

[0054] In some embodiments, the perovskite light-absorbing layer is made of ABX3 perovskite material, where A is CH3NH3. + CH(NH2)2 + Cs + or Rb + B is any combination of one or at least two of the following, where B is Pb. 2+ Sn 2+ Or Ge 2+ Any combination of one or at least two of them, X is Cl - ,Br - Or I - Any one or at least two of them.

[0055] In some embodiments, the intermediate composite layer is made of any one of ITO (indium tin oxide), IZO (indium zinc oxide), or tin oxide.

[0056] In some embodiments, the electron transport layer is made of an n-type electron transport material, which includes any one of C60, PCBM, TiO2, SnO2, ZnO, or ZnO-ZnS.

[0057] In some embodiments, the electrode layer is made of any one of Au, Ag, Al, Cu, or carbon electrodes.

[0058] In some embodiments, the thickness of the intermediate composite layer is 5nm to 20nm, for example, it can be 5nm, 8nm, 10nm, 12nm, 14nm, 16nm, 18nm or 20nm.

[0059] In some embodiments, the thickness of the hole transport layer is 1nm to 3nm, for example, it can be 1nm, 1.5nm, 2nm, 2.5nm or 3nm.

[0060] In some embodiments, the thickness of the perovskite light-absorbing layer is 400nm to 600nm, for example, it can be 400nm, 450nm, 500nm, 550nm or 600nm.

[0061] According to other embodiments of the present invention, the present invention provides a method for preparing perovskite-silicon tandem solar cells as described in some of the foregoing embodiments of the present invention, the method comprising: An intermediate composite layer is prepared on the surface of an N-type silicon substrate of a crystalline silicon bottom cell; a hole transport layer solution is spin-coated on the surface of the intermediate composite layer and annealed to obtain a hole transport layer; a perovskite light-absorbing layer, an electron transport layer and an electrode layer are sequentially prepared on the surface of the hole transport layer to obtain the perovskite crystalline silicon tandem cell. The hole transport layer solution includes self-assembled monomolecule materials and boric acid-containing surfactants.

[0062] In some embodiments, the concentration of the self-assembled monomolecule material in the hole transport layer solution is 0.5 mg / mL to 1.5 mg / mL, for example, it can be 0.5 mg / mL, 0.7 mg / mL, 0.9 mg / mL, 1.1 mg / mL, 1.3 mg / mL or 1.5 mg / mL.

[0063] In some embodiments, the concentration ratio of boric acid surfactant to self-assembled monomolecule material in the hole transport layer solution is (0.1~0.5):1, for example, it can be 0.2:1, 0.25:1, 0.3:1, 0.35:1, 0.4:1, 0.45:1 or 0.5:1.

[0064] In some embodiments, the spin coating speed is 2500 rpm to 3500 rpm, for example, 2500 rpm, 2750 rpm, 3000 rpm, 3250 rpm or 3500 rpm, and the spin coating time is 20 s to 40 s, for example, 20 s, 25 s, 30 s, 35 s or 40 s.

[0065] In some embodiments, the annealing temperature is 90°C to 110°C, for example, 90°C, 95°C, 100°C, 105°C or 110°C, and the annealing time is 8 min to 12 min, for example, 8 min, 9 min, 10 min, 11 min or 12 min.

[0066] In this invention, the preparation methods of the intermediate composite layer, perovskite light-absorbing layer, electron transport layer, and electrodes are not specifically limited. Exemplarily, the intermediate composite layer is prepared using PVD (physical vapor deposition) combined with annealing; the perovskite light-absorbing layer is prepared using spin-coating of a perovskite precursor solution combined with annealing; the electron transport layer is prepared using vacuum evaporation or atomic layer deposition; and the electrode layer is prepared using vacuum evaporation or atomic layer deposition.

[0067] According to some embodiments of the present invention, the present invention provides a photovoltaic module comprising a perovskite-silicon tandem cell as described in some of the foregoing embodiments of the present invention.

[0068] A photovoltaic (PV) module is a device that directly converts light energy into electrical energy through the photoelectric effect or photochemical effect. A PV module typically has a stacked encapsulation structure, comprising at least the following from the light-facing side to the back-light-facing side: a front cover, a first encapsulating film, a cell string layer, a second encapsulating film, and a back cover, as well as a frame surrounding the stacked structure and a junction box located on one side of the back cover.

[0069] The front cover can be made of a material with excellent light transmittance, impact resistance, corrosion resistance, and weather resistance, and may optionally include at least one of the following materials: tempered glass, plexiglass, transparent ceramics, organic fibers, or polymers. In some embodiments, the front cover may include at least one of an insulating barrier layer, a fluorinated weather-resistant layer, and a transition adhesive layer.

[0070] Back cover plates typically need to possess insulation, water resistance, aging resistance, weather resistance, and corrosion resistance. They may optionally include at least one composite back cover with tempered glass, acrylic glass, a metal back cover, or a PET film as the substrate. The PET-based composite back cover may, depending on the needs of different scenarios, include composite back covers, coated composite back covers, and co-extruded composite back covers. For example, composite back covers include polyvinyl fluoride / polyethylene terephthalate / polyvinyl fluoride (TPT) composite back covers, polyvinylidene fluoride / polyethylene terephthalate / polyvinylidene fluoride (KPK) composite back covers, and polyvinyl fluoride / polyethylene terephthalate / ethylene-vinyl acetate copolymer (TPE) composite back covers. Composite backsheets or polyvinylidene fluoride / polyethylene terephthalate / ethylene-vinyl acetate copolymer (KPE) composite backsheets, coated backsheets such as polyvinylidene fluoride / polyethylene terephthalate / coating (TPC) composite backsheets, polyvinylidene fluoride / polyethylene terephthalate (KPC) composite backsheets, or coating / polyethylene terephthalate / coating (CPC) composite backsheets, co-extruded composite backsheets, exemplary, for example, can be multilayer co-extruded polyolefin (PO) composite backsheets.

[0071] It is understandable that the material selection for the front cover and the back cover does not affect each other, and the same or different materials can be selected depending on the different application scenarios of the components (such as residential photovoltaics and building-integrated photovoltaics).

[0072] The first encapsulating film and the second encapsulating film may be selected from at least one of ethylene-vinyl acetate copolymer (EVA) film, polyvinyl octene coelastomer (POE) film, EVA-POE-EVA co-extruded film (EPE), PVB (polyvinyl butyral), polyethylene terephthalate (PET) film, or liquid silicone.

[0073] In some embodiments, the first and second encapsulating films may further include one or more functional additives selected from the group consisting of crosslinking agents, coupling agents, antioxidants, and ultraviolet absorbers, to improve the degree of crosslinking, weather resistance, adhesive strength, and anti-aging properties of the films. It is understood that the first and second encapsulating films may be made of the same or different materials.

[0074] The battery string layer comprises multiple battery strings, which can be combined in series, parallel, or series-parallel configurations to achieve current convergence and output. Furthermore, each battery string is formed by sequentially connecting multiple battery cells via connectors.

[0075] In some embodiments, at least a portion of the connector is electrically connected to the back electrode of a battery cell, and at least another portion of the connector is electrically connected to the front or back electrode of another battery cell to form a battery string. The connector may optionally include conductive elements such as solder strips, busbars, or metal clips.

[0076] The solar cell may include a semiconductor substrate, a first emitter of a first conductivity type, and a second emitter of a second conductivity type. It is understood that one of the first and second conductivity types is P-type, and the other is N-type. The semiconductor substrate may include an N-type silicon substrate or a P-type silicon substrate. N-type silicon substrates are typically formed by doping with Group V elements such as phosphorus, arsenic, or antimony, and have the characteristic that the majority charge carriers are electrons; P-type silicon substrates are typically formed by doping with Group III elements such as boron, gallium, or aluminum, and have the characteristic that the majority charge carriers are holes.

[0077] The solar cells can employ grid line designs such as no main grid (OBB), multiple main grid (MBB), or super multiple main grid (SMBB).

[0078] In some embodiments, the material of the grid line may be at least one of silver-based conductive paste or silver-coated copper composite paste. The paste uses highly conductive metal powder as the conductive substrate, and the substrate may be at least one of silver powder, copper powder, or silver-coated copper composite powder. To improve the ohmic contact performance, conductivity, and long-term weather resistance of the electrodes, a composite functional layer may be provided on the surface of the substrate or in the grid line structure. The functional layer material includes at least one of glass powder, organic carrier, nickel-based barrier layer, tin-based alloy layer, or anti-oxidation and corrosion-resistant coating.

[0079] It is understood that the solar cells can be at least one of perovskite solar cells or perovskite / crystalline silicon tandem solar cells.

[0080] In some embodiments, to improve welding performance, oxidation resistance and weather resistance, the material of the connector may preferably be a highly conductive metal material, such as at least one of silver, copper, tin, nickel or an alloy thereof.

[0081] In some embodiments, to balance conductivity and cost control requirements, the connector can be made of at least one of the following metal-clad composite materials: silver-plated copper, copper-plated silver, copper-plated aluminum, aluminum-plated copper, tin-plated copper, and nickel-plated copper. The electrical connection can be achieved through one of the following methods: laser welding, spot welding, bonding, ultrasonic welding, resistance welding, or brazing.

[0082] The frame surrounds the periphery of the stacked structure and is mostly made of aluminum alloy or steel alloy. In some embodiments, the frame may also be a fiberglass frame or a plastic frame. The inner side of the frame usually has grooves for filling with sealant to achieve a sealed bond with the stacked components formed by the front cover, the first encapsulation film, the battery string layer, the second encapsulation film, and the back cover, thereby blocking moisture and buffering external impacts.

[0083] In some implementations, the border can be assembled by connecting corner brackets.

[0084] The junction box is located on one side of the rear cover and is electrically connected to the terminals of the bus electrodes in the battery string layer via a lead-out busbar for energy extraction. The junction box typically includes a housing and cover made of weather-resistant insulating material, conductive connecting tabs inside the housing, and one or more bypass diodes. The bypass diodes are connected in parallel with sub-units of the battery string. The electrical leads of the junction box include photovoltaic-specific connectors and cables. The cables preferably use cross-linked polyethylene insulation and tinned copper core wires.

[0085] In some embodiments, the electrical components can be filled and encapsulated with potting compound to achieve insulation, heat conduction, moisture protection and fixation.

[0086] According to further embodiments of the present invention, the present invention provides a photovoltaic system comprising photovoltaic modules as described in further embodiments of the present invention.

[0087] Photovoltaic systems can be used in photovoltaic power plants, such as ground-mounted power plants, rooftop power plants, and water-based power plants. They can also be used in equipment or devices that generate electricity using solar energy, such as user solar power supplies, solar streetlights, solar cars, and solar buildings.

[0088] It is understandable that the application scenarios of photovoltaic (PV) systems are not limited to this; that is to say, PV systems can be applied in all fields that require solar energy for power generation. Taking a PV power generation system as an example, a PV system can include a PV array, a combiner box, and an inverter. The PV array can be an array combination of multiple PV modules; for example, multiple PV modules can form multiple PV arrays. The PV array is connected to the combiner box, which can collect the current generated by the PV array. The collected current flows through the inverter and is converted into AC power required by the mains power grid before being connected to the mains power grid to realize solar power supply.

[0089] The numerical range described in this embodiment of the invention includes not only the listed point values, but also any point values ​​between numerical ranges not listed. Due to space limitations and for the sake of brevity, this embodiment of the invention will not exhaustively list the specific point values ​​included in the range.

[0090] To make the technical solutions of the embodiments of the present invention clear, as follows: Figure 1 As shown, this embodiment of the invention provides a photovoltaic system 1000, including a photovoltaic module 100. For example... Figure 2 and Figure 3 As shown, the photovoltaic module consists of a frame 110, a front cover plate 120, a first encapsulating film 130, a battery string layer 140, a second encapsulating film 150, and a back cover plate 160 stacked in sequence, as well as a junction box 170. The battery string layer 140 is made by connecting perovskite crystalline silicon tandem cells in series and parallel, as provided in a specific embodiment of the present invention.

[0091] The photoelectric performance of the perovskite-silicon tandem solar cells provided in the embodiments and comparative examples of the present invention was tested in the following ways: I. Preparatory work before testing 1. Battery cell cleaning, including: Wipe the surface of the battery cells with ultrapure water, ethanol or isopropanol to remove fingerprints, dust and organic residues; After drying the solar cells with nitrogen, let them stand for 10 minutes to avoid surface contamination affecting their optical properties.

[0092] 2. Electrode contact inspection, including Electrical measurements of the solar cells were performed using a four-wire probe (Keithley 2400 series) to ensure that the contact resistance between the metal electrodes of the solar cells and the probe was <0.1Ω; Use silver paste or spring probes to secure the battery cells and avoid pressure damage.

[0093] 3. Stabilization treatment, including: Place the solar cells under standard lighting (1000W / m²). 2 After aging for 1 hour, light-induced degradation (LID) is eliminated; The temperature of the solar cells was maintained at 25℃±0.5℃ using a constant temperature stage to avoid the impact of thermal effects on carrier mobility.

[0094] 4. Equipment calibration, including: The light source spectrum was calibrated using a standard reference cell to conform to the AM1.5G standard spectral conditions, with a calibration wavelength range of 300 nm to 1200 nm. The irradiance uniformity deviation in the test area does not exceed ±2%, and the measurement error of the temperature sensor used is less than ±0.1℃.

[0095] II. Testing Equipment and Conditions 1. Core equipment IV tester: Keysight B2900A series, with a voltage resolution of 0.1mV and a current resolution of 0.1μA; Solar simulator: Class AAA compliant, with selectable pulsed or steady-state light source (e.g., Wacom WXS-200S-20). Temperature control console: Temperature regulation is achieved based on a thermoelectric cooling (TEC) module, with a control accuracy of ±0.2℃; Spectral response instrument: equipped with a quantum efficiency (QE) testing system (such as Bentham PVE300).

[0096] 2. Standard Test Conditions (STC) Irradiance: 1000W / m 2 (AM1.5G standard spectrum); Temperature: 25℃±1℃ (real-time monitoring via TEC module); Light spot uniformity: The uniformity of the light spot covering the effective area of ​​the battery is >95%.

[0097] III. Key Parameter Testing Procedures 1. Conversion efficiency (Eta) and IV characteristics (open-circuit voltage Voc, short-circuit current Isc, fill factor FF) testing Test equipment: solar simulator, IV tester and four-wire probe.

[0098] step: (1) Sample placement: Place the battery cell in the center of the light spot of the simulator, and use a light shield to block the edge of the battery cell by 5mm to avoid light leakage at the edge; (2) IV scan: Apply a scan voltage from -0.5V to Voc+0.5V through an IV tester, set the scan step size to 10mV, and record the IV characteristic curve of the battery simultaneously; (3) Parameter extraction: Extract the open-circuit voltage Voc (voltage when current = 0) and short-circuit current Isc (current when voltage = 0) from the IV curve; (4) Power and fill factor calculation: Calculate the maximum power point (P) on the IV curve. max =V mpp ×I mpp ) and fill factor FF=P max / (Voc×Isc); (5) Efficiency calculation: Conversion efficiency Eta = (P max / P in The incident light power P is calculated by multiplying the incident light power by 100%. in Calibration is performed using a calibrated standard battery.

[0099] 2. Series resistance (Rs) test Method 1: Dual-light illumination method (1) Curve measurement: at 1000W / m 2and 800W / m 2 The IV curves of the battery were measured under two irradiance conditions; (2) Resistance calculation: Calculate the slope of ΔV / ΔI of the two IV curves in the region near the short-circuit current Isc, and calculate the series resistance Rs using the formula Rs=(Voc1-Voc2) / (Isc1-Isc2).

[0100] Method 2: Four-wire pulse measurement (1) Pulse application: Use an IV tester to apply a short current pulse with a pulse width of 1ms to the battery cell to eliminate the influence of battery self-heating on the measurement. (2) Resistance deduction: According to Ohm's law ΔV=I×Rs, the series resistance Rs=ΔV / I is deduced from the measured voltage drop ΔV. It should be noted that the inherent contact resistance of the system needs to be deducted during the calculation.

[0101] 3. Parallel Resistance (Rsh) Test Method 1: Dark Current Method (1) Dark bias scanning: Under completely dark conditions, a reverse bias voltage from -1V to 0V is applied to the solar cell and scanning is performed; (2) Resistance calculation: Measure the slope of the IV characteristic in the reverse saturation current region. The parallel resistance Rsh = ΔV / ΔI, and the data point is usually taken at a bias voltage of -0.5V.

[0102] Method 2: Low-intensity IV analysis (1) Low light measurement: at 50W / m 2 The IV curve of the battery was measured under low irradiance. (2) Resistance estimation: The parallel resistance Rsh can be approximated as the reciprocal of the slope of the IV curve in the region near the open-circuit voltage Voc.

[0103] Example 1 This embodiment provides a perovskite-silicon tandem solar cell, which includes a crystalline silicon base cell, an ITO intermediate composite layer, a hole transport layer, and a Cs layer stacked sequentially. 0.22 FA 0.78 Pb(I 0.85 Br 0.15 )3 Perovskite light-absorbing layer, C 60 The intermediate composite layer consists of a tin oxide composite electron transport layer and an Ag electrode layer; the surface of the intermediate composite layer adjacent to the hole transport layer has a textured surface; the hole transport layer is made of MeO-4PACz and 4-hydroxymethylphenylboronic acid, with a mass ratio of MeO-4PACz to 4-hydroxymethylphenylboronic acid of 1:0.2, and the thickness of the hole transport layer is 2 nm.

[0104] This embodiment also provides a method for preparing the perovskite-silicon tandem solar cell, the method comprising: (1) Preparation of intermediate composite layer: ITO thin film was deposited on the surface of N-type silicon substrate of heterocrystalline silicon bottom cell by PVD. The process pressure was 0.3 Pa, the deposition power was 1 kW, the oxygen content was 0.56 vol%, the thickness of the deposited ITO thin film was 10 nm, and then annealed at 200 °C for 20 min to obtain intermediate composite layer.

[0105] (2) MeO-4PACz and 4-hydroxymethylphenylboronic acid were dissolved in isopropanol to prepare a hole transport layer solution with a MeO-4PACz concentration of 1 mg / mL and a 4-hydroxymethylphenylboronic acid concentration of 0.2 mg / mL. The hole transport layer solution was spin-coated at 3000 rpm for 30 s and then annealed at 100 °C for 10 min to obtain a hole transport layer with a thickness of 2 nm.

[0106] (3) Fabrication of a perovskite light-absorbing layer on the surface of the hole transport layer: specifically including: According to Cs 0.22 FA 0.78 Pb(I 0.85 Br 0.15 In a stoichiometric ratio of 3, CsI, FAI, PbBr2, PbCl2, PbI2, and MACl were dissolved in a mixed solvent of DMF and DMSO at a volume ratio of 4:1. The mixture was stirred thoroughly for at least 12 hours to finally form 1.7 mol / L CsI. 0.22 FA 0.78 Pb(I 0.85 Br 0.15 3. Perovskite precursor solution. The perovskite precursor solution was then coated onto the self-assembled layer by spin coating. Specifically, the spin coating was performed at 5000 rpm for 50 s with an acceleration of 1000 rpm. At the 35th second, 300 μL of anisole was added dropwise. Finally, the layer was annealed at 100 °C for 20 min to form a perovskite light-absorbing layer with a thickness of 500 nm.

[0107] (4) Preparation of passivation layer: Spin-coating a solution of piperazine monoiodine material with a concentration of 0.3 mg / mL onto the surface of the perovskite light-absorbing layer with an isopropanol solution at a spin coating speed of 4000 rpm for 25 s, followed by annealing at 100 °C for 10 min to form a passivation layer with a thickness of 2 nm.

[0108] (5) Fabrication of the electron transport layer: First, C is prepared on the surface of the passivation layer by vacuum evaporation. 60 The electron transport layer was vacuum-deposited at a vacuum level of 5 × 10⁻⁶. -4 Pa, evaporation rate is 0.15 A / s, C 60 The electron transport layer is 10 nm thick; then in C 60A tin oxide electron transport layer was deposited on the surface of the electron transport layer by atomic layer deposition (ALD). The ALD temperature was 85°C, tetra(dimethylamino)tin was used as the tin source, the tin source emission rate was 0.5 sccm, the purge time was 5 s, the water source emission rate and purge time were 0.5 s and 5 s respectively, and the cycle number was 130 times. At this time, the tin oxide thickness was 15 nm.

[0109] (6) Electrode layer preparation: A metal electrode is prepared by vacuum evaporation. In the metal evaporation chamber, a silver electrode with a thickness of 1000 nm is formed on the surface of the electron transport layer by a thermal evaporation process. The vacuum degree of the evaporation chamber is 5 × 10⁻⁶. -4 Pa, evaporation rate is 2A / s.

[0110] Example 2 This embodiment provides a perovskite-silicon tandem solar cell. Except that the hole transport layer of the perovskite-silicon tandem solar cell is made of 4PACz and 4-aminomethylphenylboronic acid in the same mass ratio as MeO-4PACz and 4-hydroxymethylphenylboronic acid in Embodiment 1, and the thickness of the hole transport layer is 1 nm, all other aspects are the same as in Embodiment 1. This embodiment also provides a method for fabricating the perovskite-silicon tandem solar cell. Except for the hole transport layer being prepared by the following method, the method is the same as in Example 1. The method for preparing the hole transport layer includes: A hole transport layer solution with a 4PACz concentration of 0.5 mg / mL and a 4-aminomethylphenylboronic acid concentration of 0.1 mg / mL was prepared. The hole transport layer solution was spin-coated at 2500 rpm for 20 s, and then annealed at 90 °C for 8 min to obtain a hole transport layer with a thickness of 1 nm.

[0111] Example 3 This embodiment provides a perovskite-silicon tandem solar cell. Except that the hole transport layer of the perovskite-silicon tandem solar cell is made of Me-2PACz and 4-carboxyphenylboronic acid in the same mass ratio as MeO-4PACz and 4-hydroxymethylphenylboronic acid in Embodiment 1, and the hole transport layer is 3nm thick, all other aspects are the same as in Embodiment 1. This embodiment also provides a method for fabricating the perovskite-silicon tandem solar cell. Except for the hole transport layer being prepared by the following method, the method is the same as in Example 1. The method for preparing the hole transport layer includes: A hole transport layer solution with a Me-2PACz concentration of 1.5 mg / mL and a 4-carboxyphenylboronic acid concentration of 0.3 mg / mL was prepared. The hole transport layer solution was spin-coated at 3500 rpm for 40 s and then annealed at 110 °C for 12 min to obtain a hole transport layer with a thickness of 3 nm.

[0112] Example 4 This embodiment provides a perovskite-silicon tandem solar cell. Except that the hole transport layer of the perovskite-silicon tandem solar cell is made of MeO-4PACz and 4-(3-hydroxypropyl)phenylboronic acid in the same mass ratio as MeO-4PACz and 4-hydroxymethylphenylboronic acid in Example 1, the rest is the same as in Example 1. This embodiment also provides a method for preparing the perovskite-silicon tandem solar cell, except that 4-(3-hydroxypropyl)phenylboronic acid of equal concentration is used instead of 4-hydroxymethylphenylboronic acid in the hole transport layer solution, and the rest is the same as in Example 1.

[0113] Example 5 This embodiment provides a perovskite-silicon tandem solar cell. Except that the hole transport layer of the perovskite-silicon tandem solar cell is made of MeO-4PACz and 6-(hydroxymethyl)pyridine-3-boronic acid in the same mass ratio as MeO-4PACz and 4-hydroxymethylphenylboronic acid in Embodiment 1, the rest is the same as in Embodiment 1. This embodiment also provides a method for preparing the perovskite-silicon tandem solar cell, except that 6-(hydroxymethyl)pyridine-3-boric acid of equal concentration is used instead of 4-hydroxymethylphenylboronic acid in the hole transport layer solution, and the rest is the same as in Example 1.

[0114] Example 6 This embodiment provides a perovskite-silicon tandem solar cell. Except that the hole transport layer of the perovskite-silicon tandem solar cell is made of MeO-4PACz and (5-(hydroxymethyl)pyridin-2-yl)boronic acid in the same mass ratio as MeO-4PACz and 4-hydroxymethylphenylboronic acid in Example 1, the rest is the same as in Example 1. This embodiment also provides a method for preparing the perovskite-silicon tandem solar cell, except that (5-(hydroxymethyl)pyridin-2-yl)boronic acid of equal concentration is used instead of 4-hydroxymethylphenylboronic acid in the hole transport layer solution, the rest is the same as in Example 1.

[0115] Example 7 This embodiment provides a perovskite-silicon tandem solar cell, which is the same as in Embodiment 1 except that the mass ratio of 4-hydroxymethylphenylboronic acid to MeO-4PACz in the hole transport layer of the perovskite-silicon tandem solar cell is 0.1:1. This embodiment also provides a method for preparing the perovskite-silicon tandem solar cell, which is the same as in Example 1 except that the concentration of 4-hydroxymethylphenylboronic acid in the hole transport layer solution is 0.1 mg / mL.

[0116] Example 8 This embodiment provides a perovskite-silicon tandem solar cell, which is the same as in Embodiment 1 except that the mass ratio of 4-hydroxymethylphenylboronic acid to MeO-4PACz in the hole transport layer of the perovskite-silicon tandem solar cell is 0.5:1. This embodiment also provides a method for preparing the perovskite-silicon tandem solar cell, which is the same as in Example 1 except that the concentration of 4-hydroxymethylphenylboronic acid in the hole transport layer solution is 0.5 mg / mL.

[0117] Example 9 This embodiment provides a perovskite-silicon tandem solar cell, which is the same as in Embodiment 1 except that the mass ratio of 4-hydroxymethylphenylboronic acid to MeO-4PACz in the hole transport layer of the perovskite-silicon tandem solar cell is 0.05:1. This embodiment also provides a method for preparing the perovskite-silicon tandem solar cell, which is the same as in Example 1 except that the concentration of 4-hydroxymethylphenylboronic acid in the hole transport layer solution is 0.05 mg / mL.

[0118] Example 10 This embodiment provides a perovskite-silicon tandem solar cell, which is the same as in Embodiment 1 except that the mass ratio of 4-hydroxymethylphenylboronic acid to MeO-4PACz in the hole transport layer of the perovskite-silicon tandem solar cell is 0.7:1. This embodiment also provides a method for preparing the perovskite-silicon tandem solar cell, which is the same as in Example 1 except that the concentration of 4-hydroxymethylphenylboronic acid in the hole transport layer solution is 0.7 mg / mL.

[0119] Comparative Example 1 This comparative example provides a perovskite-silicon tandem solar cell, which is the same as Example 1 except that the hole transport layer of the perovskite-silicon tandem solar cell only includes MeO-4PACz. This comparative example also provides a method for preparing the perovskite-silicon tandem solar cell, which is the same as in Example 1 except that 4-hydroxymethylphenylboronic acid is not added to the hole transport layer solution.

[0120] like Figure 4 As shown, in the perovskite-silicon tandem solar cell provided in Example 1, the intermediate composite layer 1412 disposed on the surface of the N-type silicon substrate of the crystalline silicon bottom cell 1411 has a textured structure. One end of the boric acid surfactant 1413b in the hole transport layer is anchored to the surface of the intermediate composite layer 1412, effectively overcoming the problem of aggregation of self-assembled monomolecule materials 1413a. And as... Figure 8 As shown, in Comparative Example 1, when no boric acid surfactant is added, the self-assembled monomolecule material 1413a is severely aggregated on the surface of the intermediate composite layer 1412.

[0121] according to Figure 5 and Figure 9 The SEM images of the perovskite absorbing layers prepared in Example 1 and Comparative Example 1 show that the perovskite grain size in the perovskite absorbing layer of Example 1 is significantly larger than that in the perovskite absorbing layer of Comparative Example 1. This indicates that the introduction of a boric acid-containing surfactant into the hole transport layer promotes the growth of perovskite grains in the subsequent perovskite absorbing layer. The perovskite grain size in the perovskite absorbing layer of Example 1 is significantly larger than that in the perovskite absorbing layer of Comparative Example 1. According to... Figure 6 and Figure 10 The fluorescence lifetime scanning images of the perovskite light-absorbing layers prepared in Example 1 and Comparative Example 1 are shown. Example 1 shows a uniform green color, which proves that MeO-4PACz containing boric acid surfactant effectively suppresses interface defects on the textured substrate, uniformly anchors the perovskite, significantly reduces global nonradiative recombination, and improves the film quality. In contrast, Comparative Example 1 shows a large-scale and non-uniform nonradiative recombination.

[0122] Performance testing: The hole transport layer solutions from Example 1 and Comparative Example 1 were respectively dropped onto glass surfaces to form thin film layers. Water was then dropped onto the surface of each film layer, and the contact angles of the thin film layers were tested. The contact angles of the films obtained from the hole transport layer solutions in Example 1 and Comparative Example 1 are shown below. Figure 7 and Figure 11 As shown, the contact angle of the film obtained by the hole transport layer solution in Example 1 is only 51.67°, while the contact angle of the film obtained by the hole transport layer solution in Comparative Example 1 is as high as 71.08°. The smaller the contact angle, the better the wettability of the film layer, the easier the film spreads out, and the better the film formation effect. The test results of Example 1 and Comparative Example 1 show that the introduction of boric acid surfactant into the hole transport layer in this invention is beneficial to the uniform film formation of the perovskite light-absorbing layer.

[0123] The photoelectric conversion efficiency (Eta), open-circuit voltage (Voc), short-circuit current density (Jsc), and fill factor (FF) of all the above embodiments and comparative examples were tested. The test results are shown in Table 1.

[0124] Table 1 Based on the test results of Examples 1 to 8 in Table 1 and Figure 12 Comparing the JV curves of Example 1 and Comparative Example 1, the present invention, by introducing boric acid surfactants with structures of Formulas 1 to 3 into the hole transport layer of the self-assembled monomolecular material, shows a significant improvement in open-circuit voltage, short-circuit current, fill factor, and photoelectric conversion efficiency of the perovskite-silicon tandem solar cell compared to Comparative Example 1 without the addition of boric acid surfactants.

[0125] Based on the test results of Examples 1, 9, and 10, controlling the amount of boric acid surfactant added within a suitable range allows the photoelectric performance improvement of the perovskite-silicon tandem solar cell to be within the optimal range. If the amount of boric acid surfactant added is too small, it is insufficient to overcome the self-assembled monomolecule aggregation and the vertical distribution of A-site ions in the uniform perovskite light-absorbing layer, resulting in an unsatisfactory photoelectric performance improvement of the perovskite-silicon tandem solar cell. If the amount of boric acid surfactant added is too large, due to its own insulating properties, it hinders carrier transport, leading to a decrease in current and thus affecting the photoelectric performance of the perovskite-silicon tandem solar cell.

Claims

1. A perovskite-silicon tandem solar cell, characterized in that, The perovskite-silicon tandem solar cell includes a crystalline silicon base cell, an intermediate composite layer, a hole transport layer, a perovskite light-absorbing layer, an electron transport layer, and an electrode layer stacked sequentially. The perovskite light-absorbing layer is made of ABX3 perovskite material; The surface of the intermediate composite layer adjacent to the hole transport layer has a textured surface. The hole transport layer is made of a self-assembled monomolecular material and a boric acid-containing surfactant. The boric acid surfactant includes a boric acid compound, which includes a boric acid group and a passivating group. The boric acid group is anchored to the intermediate composite layer, and the passivating group is coupled to the A-site cation of the perovskite material in the perovskite light-absorbing layer via hydrogen bonds.

2. The perovskite-silicon tandem solar cell as described in claim 1, characterized in that, The boric acid surfactant has any one or a combination of at least two of the boric acid compounds shown in Formulas 1 to 3, wherein R in Formulas 1 to 3 includes any one of amino, carboxyl or hydroxyl groups, and n is an integer from 0 to 4. ； ； 。 3. The perovskite-silicon tandem solar cell as described in claim 2, characterized in that, The boric acid compound includes any one or a combination of at least two of 4-hydroxymethylphenylboronic acid, 4-aminomethylphenylboronic acid, 4-carboxyphenylboronic acid, 4-(3-hydroxypropyl)phenylboronic acid, 6-(hydroxymethyl)pyridine-3-boronic acid, or (5-(hydroxymethyl)pyridine-2-yl)boronic acid.

4. The perovskite-silicon tandem solar cell as described in claim 1, characterized in that, In the hole transport layer, the mass ratio of boric acid surfactant to self-assembled monomolecule material is (0.1~0.5):

1.

5. The perovskite-silicon tandem solar cell as described in claim 1, characterized in that, The self-assembled monomolecular material package includes any one or a combination of at least two of 2PACz, 4PACz, derivatives of 2PACz, or derivatives of 4PACz. And / or, the perovskite light-absorbing layer is made of ABX3 perovskite material, where A is CH3NH3. + CH(NH2)2 + Cs + or Rb + B is any combination of one or at least two of the following, where B is Pb. 2+ Sn 2+ Or Ge 2+ Any combination of one or at least two of them, X is Cl - ,Br - Or I - Any one or at least two of the above; at least two combinations of the above. And / or, the material of the intermediate composite layer includes any one of ITO, IZO or tin oxide; And / or, the thickness of the intermediate composite layer is 5nm~20nm; And / or, the thickness of the hole transport layer is 1nm~3nm; And / or, the thickness of the perovskite light-absorbing layer is 400nm~600nm.

6. A method for preparing a perovskite-silicon tandem solar cell as described in any one of claims 1 to 5, characterized in that, The preparation method includes: An intermediate composite layer is prepared on the surface of an N-type silicon substrate of a crystalline silicon bottom cell; a hole transport layer solution is spin-coated on the surface of the intermediate composite layer and annealed to obtain a hole transport layer; a perovskite light-absorbing layer, an electron transport layer and an electrode layer are sequentially prepared on the surface of the hole transport layer to obtain the perovskite crystalline silicon tandem cell; the hole transport layer solution includes a self-assembled monomolecular material and a boric acid surfactant.

7. The preparation method according to claim 6, characterized in that, In the hole transport layer solution, the concentration of the self-assembled monomolecule material is 0.5 mg / mL to 1.5 mg / mL; And / or, in the hole transport layer solution, the concentration ratio of boric acid surfactant to self-assembled monomolecule material is (0.1~0.5):

1.

8. The preparation method according to claim 6, characterized in that, The spin coating speed is 2500 rpm to 3500 rpm, and the spin coating time is 20 s to 40 s; And / or, the annealing temperature is 90℃~110℃, and the annealing time is 8min~12min.

9. A photovoltaic module, characterized in that, The photovoltaic module includes a perovskite-silicon tandem cell as described in any one of claims 1 to 5.

10. A photovoltaic system, characterized in that, The photovoltaic system includes the photovoltaic module as described in claim 9.

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