A perovskite photovoltaic cell and its preparation method

Abstract

This invention discloses a perovskite photovoltaic cell and its preparation method, belonging to the field of perovskite solar cell technology. The perovskite photovoltaic cell device of this invention adopts an innovative layered structure, consisting of, from bottom to top, a substrate, an anode layer, a hole transport layer, a SAM+IL modified layer, and a SAM-doped CsPbI layer. x Br 3‑x (x=2~3) Perovskite light-absorbing layer, SAM+IL modified layer, composed of fullerene C 60 The electron transport layer consists of a nickel oxide layer and a tin dioxide (SnO2) layer, as well as a cathode layer. The nickel oxide hole transport layer is deposited using electron beam evaporation. 60 The perovskite solar cell and SnO2 layers were prepared using thermal evaporation and atomic layer deposition processes. This perovskite solar cell device not only boasts excellent performance but also features low processing costs and suitability for large-area deposition, effectively overcoming the technical bottlenecks of traditional devices. It provides a new material and technological pathway for the development of high-efficiency perovskite photovoltaic devices and has significant industrial application value in the field of perovskite solar cells.

Description

Technical Field

[0001] This invention relates to the field of perovskite solar cell technology, and particularly to a perovskite photovoltaic cell and its preparation method. Background Technology

[0002] Perovskite solar cells (PSCs) are widely recognized as the core development direction of next-generation photovoltaic technology due to their high efficiency, low cost, and solution processing advantages. Among them, the inorganic perovskite material CsPbI₂Br has an ideal bandgap of 1.80-1.92 eV, making it suitable for both single-junction solar cells and as a sub-cell in the construction of high-efficiency tandem devices. Its theoretical power conversion efficiency (PCE) is as high as 24.3%, demonstrating great application potential. However, the actual PCE of current CsPbI₂Br-based inverse PSCs only reaches about 70% of the theoretical limit. The key bottlenecks are concentrated in the carrier loss induced by interface defects and the low transport efficiency caused by energy level mismatch.

[0003] CsPbI2Br films prepared by low-temperature solution methods inevitably contain a large number of bulk and interfacial defects (such as Pb). 2+ Vacancies and I / Br ion absences become carrier recombination centers, leading to severe nonradiative recombination, significantly shortening carrier lifetime and reducing open-circuit voltage (V). oc Meanwhile, hole transport layers (such as NiO) x The interface roughness and chemical incompatibility between the perovskite layer and the electron transport layer further exacerbate the interface defect density. Additionally, the traditional hole transport layer (NiO) x There is an energy level shift between the valence band apex (VBM) of CsPbI2Br and the valence band edge of CsPbI2Br, and the electron transport layer (such as C) 60 Insufficient matching between the conduction band bottom (CBM) of / SnO2 and the conduction band of perovskite leads to interfacial charge accumulation and recombination loss, directly affecting the fill factor (FF) and device stability. In addition, single interface modification strategies (such as optimizing only the bottom or top interface) are difficult to synergistically regulate the energy level arrangement of the two interfaces, and the carrier transport path is not fully optimized.

[0004] Although self-assembled monolayer (SAM) technology achieves defect passivation by coordinating with perovskite surfaces using groups such as phosphonic acid and carboxylic acid, its molecular design has significant shortcomings: 1) Unclear structure-activity relationship: Existing SAM materials mostly rely on fixed functional groups and lack systematic design for controlling the electron-donating / withdrawing units, dipole moments, and interface energy levels of molecules, making it difficult to accurately match the energy level requirements of dual interfaces; 2) Lack of synergistic effect: Traditional methods do not introduce functional additives to form a synergistic system with SAM, and the passivation efficiency of a single SAM molecule for complex interface defects is limited, and it cannot effectively regulate interface wettability and ion migration behavior.

[0005] Ionic liquids (ILs), as emerging functional materials, offer new insights into solving the aforementioned problems due to their unique properties: 1) Passivation capability for multiple defects: The cations and anions of ILs can interact with unsaturated Pb on the perovskite surface. 2+ 1) Halogen vacancies form coordination bonds, which, together with the anchoring groups of SAM, achieve multiple passivation of defects and suppress nonradiative recombination; 2) Interfacial energy level regulation characteristics: The dipole moment and polarity of IL molecules can adjust the interfacial charge distribution, which, together with the electron-donating / withdrawing units of SAM, enables NiO x The energy levels of the perovskite bottom interface and the perovskite / electron transport layer top interface are precisely aligned, reducing the charge transport barrier; 3) Process compatibility optimization: The high boiling point and low volatility of IL can improve the crystallization kinetics of perovskite films during solution spin coating, while its nanoscale lubrication effect can reduce the interface roughness of the electron transport layer during evaporation, improving the interlayer contact quality. However, in the existing technology, the application of IL in CsPbI2BrPSCs is still limited to single interface modification or bulk doping, without forming a synergistic modification system with SAM molecules. It is difficult to simultaneously achieve dual interface defect passivation, energy level matching optimization, and carrier transport path reconstruction, resulting in limited improvement in device efficiency and stability. Summary of the Invention

[0006] The purpose of this invention is to provide a modulation technology for trans-CsPbI2Br perovskite solar cells (PSCs) based on a synergistic hybrid system of self-assembled monolayer (SAM) and ionic liquid (IL). Through the synergistic effect of the novel SAM molecular system and IL, multiple passivation of interface defects and precise energy level matching are achieved, solving the problems of low efficiency and poor stability of traditional perovskite solar cells caused by interface defects and energy level mismatch. At the same time, it provides a low-cost, large-area, high-efficiency and stable device and its fabrication method.

[0007] The objective of this invention is achieved through the following technical solution:

[0008] A perovskite photovoltaic cell device, the perovskite solar cell device comprising, from bottom to top, a substrate, an anode layer, a hole transport layer, a perovskite + SAM light absorption layer, a SAM + IL layer, an electron transport layer and a cathode layer.

[0009] The SAM absorber layer comprises CsPbI. x Br 3-x The electron transport layer is doped with SAM, where x = 2~3, and includes a nickel oxide layer deposited by electron beam evaporation. The electron transport layer comprises fullerene C layers stacked sequentially from bottom to top. 60 Layer with SnO2, the C 60The SAM layer and SnO2 layer were obtained by thermal evaporation and atomic layer deposition, respectively. The SAM molecules bind to perovskite defects through functional anchoring groups to achieve defect passivation, and the interface energy level matching is optimized by molecular electron-donating / withdrawing units and dipole moment regulation.

[0010] The perovskite solar cell device adopts a bottom-up stacked structure, specifically including:

[0011] Substrate: As the device substrate, it can be glass, flexible polymer (such as PET), etc.

[0012] Anode layer: metals (such as aluminum, silver-magnesium alloy, silver, gold), metal oxides (such as indium tin oxide, fluorine-doped tin dioxide, zinc oxide, indium gallium zinc oxide) or poly(3,4-ethylenedioxythiophene)-poly(styrene sulfonic acid) (PEDOT:PSS) and their modified products are used.

[0013] Hole transport layer: Contains nickel oxide (NiO) deposited by electron beam evaporation. x The layer may further include an electron blocking layer and / or an exciton blocking layer, in conjunction with NiO. x These layers together constitute the hole transport layer, optimizing hole transport and interface energy level matching;

[0014] SAM+IL layer (bottom interface modification layer): Deposited between the hole transport layer and the perovskite light absorption layer, the functional anchoring groups of SAM molecules (such as phosphonic acid groups) bind to perovskite defects, and the cations and anions of IL coordinate with unsaturated ions on the perovskite surface, achieving defect passivation synergistically; simultaneously, NiO is optimized through molecular electron-donating / withdrawing units and IL dipole moment modulation. x / CsPbI2Br interface energy level structure;

[0015] Perovskite light-absorbing layer: composition is CsPbI x Br 3-x SAM doping (x=2~3) suppresses crystal defects and improves film quality and light absorption efficiency.

[0016] SAM+IL layer (top interface modification layer): deposited between the perovskite light absorption layer and the electron transport layer, working synergistically with the bottom interface SAM+IL layer to modify the CsPbI2Br / electron transport layer interface and reduce interface recombination loss.

[0017] Electron transport layer: consisting of fullerene C layers stacked sequentially from bottom to top. 60 The layer and the tin dioxide (SnO2) layer are applied by thermal evaporation and atomic layer deposition, and may further include a hole blocking layer and / or an exciton blocking layer to optimize electron transport and interface contact;

[0018] Cathode layer: The material is the same as the anode layer, and it forms an ohmic contact with the electron transport layer to collect electrons.

[0019] Through synergistic modification of the bottom interface SAM+IL layer (NiOx / CsPbI2Br) and the top interface SAM+IL layer (CsPbI2Br / electron transport layer), the specific anchoring groups of SAM and the ionic coordination of IL achieve dual passivation of interface defects, reducing non-radiative recombination losses. At the same time, the dipole moment of IL and the electron-donating / withdrawing units of SAM molecules synergistically regulate the interface charge distribution, optimize the carrier transport path, and significantly improve the open-circuit voltage (Voc) and fill factor (FF).

[0020] SAM molecules bind to lead defects on the perovskite surface through functional anchoring groups (such as phosphonic acid groups), and the cations and anions of IL coordinate with halogen vacancies. The two work synergistically to enhance the defect passivation effect. Furthermore, through molecular structure design (such as introducing cyano groups and adjusting electron-donating / withdrawing units) and polarity regulation of IL, precise energy level matching with the transport layer is achieved.

[0021] Furthermore, the hole transport layer further includes an electron blocking layer and / or an exciton blocking layer; the electron transport layer further includes a hole blocking layer and / or an exciton blocking layer; an anode buffer layer is further included between the anode layer and the hole transport layer; and a cathode buffer layer is further included between the cathode layer and the electron transport layer.

[0022] A method for fabricating a perovskite solar cell device mainly includes the following steps:

[0023] Step S1. Obtain the substrate and ultrasonically clean it sequentially using acetone, micron-level semiconductor-specific detergent, deionized water, and isopropanol, then dry it.

[0024] Step S2. Prepare an anode layer on the substrate;

[0025] Step S3. A nickel oxide layer is deposited on the anode layer using electron beam evaporation to serve as a hole transport layer;

[0026] Step S4. Deposit a hybrid SAM and IL layer on the hole transport layer;

[0027] Step S5. Deposit components including CsPbI on the SAM and IL mixed layer. x Br 3-x A perovskite light-absorbing layer doped with SAM, where x = 2~3;

[0028] Step S6. Deposit a mixed film of SAM and IL on the perovskite light-absorbing layer;

[0029] Step S7. Fullerene C is sequentially deposited on the SAM and IL mixed film using thermal evaporation and atomic layer deposition.60 The layer consists of a SnO2 layer and an electron transport layer.

[0030] Step S8. Prepare a cathode layer on the electron transport layer.

[0031] The preparation method includes the following core steps:

[0032] 1. Substrate cleaning (step S1): The substrate is ultrasonically cleaned in sequence with acetone, micron-level semiconductor-specific detergent, deionized water and isopropanol and then dried to ensure surface cleanliness.

[0033] 2. Anode layer preparation (step S2): An anode layer is formed on the substrate by methods such as evaporation, spin coating or sputtering.

[0034] 3. Hole transport layer preparation (step S3): Nickel oxide (NiO) is deposited using electron beam evaporation. x () layer, which can selectively be formed between the anode layer and NiO x An anodic buffer layer is formed between the layers, or in NiO x An electron blocking layer and / or an exciton blocking layer are formed on the layer, which together constitute the hole transport layer.

[0035] 4. Deposition of the bottom interface SAM+IL layer (step S4): A modified layer is formed on the surface of the hole transport layer by a solution method using a mixed solution of SAM and IL, thereby controlling the NiO content. x Surface wettability and defect status.

[0036] 5. Preparation of perovskite light-absorbing layer (step S5): CsPbI x Br 3-x The precursor solution (doped SAM) was spin-coated onto the bottom interface SAM+IL layer and then annealed to form a high-quality polycrystalline thin film.

[0037] 6. Top interface SAM+IL layer deposition (step S6): A modified layer is formed on the surface of the perovskite light absorption layer by solution method to passivate top interface defects and optimize energy level matching.

[0038] 7. Electron transport layer preparation (step S7): C is deposited sequentially using thermal evaporation and atomic layer deposition. 60 The perovskite light-absorbing layer and the SnO2 layer can be selectively combined. 60 Hole blocking layers and / or exciton blocking layers are formed between the layers to improve electron extraction efficiency.

[0039] Cathode layer preparation (step S8): A cathode layer is formed on the electron transport layer by vapor deposition. A cathode buffer layer can be selectively formed between the electron transport layer and the cathode layer to improve the interface contact.

[0040] By combining solution spin coating and thermal evaporation processes, large-area uniform fabrication of SAM and IL-modified trans-CsPbI2BrPSCs was achieved, with a power conversion efficiency (PCE) exceeding 16%, which is significantly higher than that of traditional unmodified devices.

[0041] The high boiling point and low volatility of IL improve the crystallization kinetics of perovskite thin films and inhibit phase separation and interface degradation; the synergistic effect of SAM and IL enhances the stability of the device and meets the needs of practical applications.

[0042] Low cost and process compatibility: The transport layer is prepared using mature processes such as electron beam evaporation and thermal evaporation, combined with solution deposition of SAM, IL and perovskite layers, which reduces the preparation cost and is suitable for large-area industrial production.

[0043] Furthermore, the anode layer and the cathode layer are metals or metal oxides or poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonic acid) and their modified products; wherein the metal is aluminum, silver-magnesium alloy, silver or gold; and the metal oxide is one or more of indium tin oxide, fluorine-doped tin dioxide, zinc oxide and indium gallium zinc oxide.

[0044] Furthermore, step S3 also includes: forming an anode buffer layer between the anode layer and the hole transport layer.

[0045] Furthermore, step S3 also includes: forming an electron blocking layer and / or an exciton blocking layer on the nickel oxide layer; wherein the nickel oxide layer and the electron blocking layer and / or exciton blocking layer together serve as the hole transport layer.

[0046] Furthermore, step S7 also includes: forming a hole-blocking layer and / or an exciton-blocking layer on the perovskite light-absorbing layer, wherein the fullerene C 60 The SnO2 layer, the hole blocking layer, and / or the exciton blocking layer together serve as the electron transport layer.

[0047] Furthermore, step S8 further includes forming a cathode buffer layer between the electron transport layer and the cathode layer.

[0048] The beneficial effects of this invention are:

[0049] (1) Defect passivation and efficiency improvement: SAM and IL effectively reduce the density of bulk phase and interface defects in perovskite films, suppress nonradiative recombination, and improve Voc and FF through dual-interface synergistic modification, achieving PCE of over 16%;

[0050] (2) Improved energy level matching and stability: The interface energy level arrangement is optimized by molecular structure design and synergistic regulation of IL to reduce charge accumulation and recombination loss; at the same time, the degradation of perovskite is inhibited, and the device lifespan is extended.

[0051] (3) Process advantages and industrialization potential: The combination of low-cost solution method and vapor deposition process supports large-area uniform deposition, providing a feasible path for the industrialization of high-efficiency and long-life perovskite photovoltaic devices. Attached Figure Description

[0052] Figure 1 This is a schematic diagram of the stacked structure of the perovskite solar cell device in an embodiment of the present invention;

[0053] Figure 2 This is a schematic diagram of the chemical structure of the self-assembly material and ionic liquid involved in this invention;

[0054] Figure 3 This is a process flow diagram of the perovskite solar cell device fabrication method of the present invention;

[0055] Figure 4 The current density-voltage (JV) characteristic curve of the perovskite solar cell device prepared in Example 1 is shown.

[0056] Figure 5 The current density-voltage (JV) characteristic curve of the perovskite solar cell device prepared in Example 2 is shown.

[0057] Figure 6 The current density-voltage (JV) characteristic curve of the perovskite solar cell device prepared in Example 3 is shown.

[0058] Figure 7 The current density-voltage (JV) characteristic curve of the perovskite solar cell device prepared in Example 4 is shown.

[0059] Figure 8 The current density-voltage (JV) characteristic curve of the perovskite solar cell device prepared in Example 5 is shown.

[0060] Figure 9 The current density-voltage (JV) characteristic curve of the perovskite solar cell device prepared in Example 6 is shown. Detailed Implementation

[0061] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0062] like Figure 1As shown, this invention discloses a perovskite solar cell device, comprising, from bottom to top, a substrate, an anode layer, a hole transport layer, and a SAM-doped CsPbI layer. x Br 3-x (x=2~3) Perovskite light-absorbing layer, SAM+IL modified layer, composed of fullerene C 60 The perovskite light-absorbing layer consists of an electron transport layer composed of a perovskite layer and a tin dioxide (SnO2) layer, as well as a cathode layer. The perovskite light-absorbing layer is composed of CsPbI. x Br 3-x Doped SAM, where x = 2~3, the hole transport layer includes nickel oxide (NiO). x The electron transport layer includes a C layer and an electron blocking layer and / or an exciton blocking layer. 60 The layer includes a hole-blocking layer and / or an exciton-blocking layer. Of course, in other embodiments, the hole transport layer may consist only of a nickel oxide layer, and the electron transport layer may consist only of C… 60 The layers can be selectively designed according to actual conditions, and no excessive restrictions are imposed here. In addition, an anode buffer layer can also be provided between the anode layer and the hole transport layer; a cathode buffer layer can also be provided between the cathode layer and the electron transport layer.

[0063] See Figure 2 The chemical structures of the self-assembled materials and ionic liquids involved are presented. The defect-anchoring groups (such as phosphonic acid groups), tunable electron-donating / withdrawing units, and the anion and cation structures of ILs are revealed, providing a chemical structural basis for understanding the synergistic modification mechanism of materials.

[0064] This invention utilizes the synergistic effect of self-assembled monolayers (SAM) and ionic liquids (ILs) to construct a dual-interface modification system, achieving efficient passivation of interface defects and precise control of energy level structure in trans-CsPbI2Br perovskite solar cells. The specific mechanism is as follows:

[0065] 1. Dual passivation of interface defects and energy level matching optimization:

[0066] Through the bottom interface SAM+IL layer (NiO) x Synergistic modification of the CsPbI2Br layer and the top interface SAM+IL layer (CsPbI2Br / electron transport layer) forms a dual-functional interface regulation system of "defect passivation-energy level matching":

[0067] 1) Bottom interface modification (NiO) x / Perovskite): NiO was prepared by electron beam evaporation. x Following the hole transport layer, a SAM+IL hybrid layer was constructed on its surface using a solution method. The functional anchoring groups of the SAM molecules (such as phosphonic acid groups) and the Pb at the perovskite substrate interface... 2+Vacancy-specific binding, IL cations and anions bind to halogen vacancies (I - / Br - (The vacancy) forms a coordination bond, and the two work together to passivate interface defects and reduce the density of nonradiative recombination centers. Simultaneously, the electron-donating / withdrawing units of the SAM molecule and the dipole moment of the IL jointly regulate the NiO. x The energy level shift between the valence band peak (VBM) and the edge of the perovskite valence band allows for precise matching of the valence band energy levels between the hole transport layer and the perovskite light absorption layer, promoting efficient hole injection into NiO. x layer.

[0068] 2) Top interface modification (perovskite / electron transport layer): A SAM+IL hybrid layer is spin-coated onto the surface of the perovskite light-absorbing layer. SAM molecules passivate uncoordinated Pb on the perovskite surface through anchoring groups. 2+ The polar ionic groups of IL improve interfacial wettability and inhibit ion migration, synergistically reducing the defect state density at the top interface. Simultaneously, by modulating the dipole moment of the SAM molecule and the polar environment of IL, the perovskite conduction band bottom (CBM) and electron transport layer (such as C) can be optimized. 60 The matching degree of the conduction band energy level of / SnO2 reduces the electron transport barrier and improves the electron injection efficiency.

[0069] 2. Synergistic enhancement mechanism:

[0070] 1) Defect passivation synergistic effect: The directional anchoring effect of SAM molecules complements the ion coordination effect of IL, and SAM specifically captures Pb. 2+ The defects are covered by IL, which covers halogen vacancies and inhibits ion migration. This dual effect reduces the interface defect density and significantly prolongs the carrier lifetime.

[0071] 2) Synergistic effect of energy level regulation: SAM molecules lower the interface energy level by introducing electron-withdrawing groups or raise the energy level by introducing electron-donating groups, and combine the dipole moment of IL to regulate the interface charge distribution to construct an ideal energy level aligned structure.

[0072] 3) Carrier transport optimization: Dual-interface modification synergistically shortens the carrier transport path at the interface and reduces charge accumulation.

[0073] 3. Synergistic advantages of materials and processes:

[0074] SAM molecules doped into the perovskite precursor solution can effectively suppress grain boundary defects in CsPbI2Br films and improve crystal orientation consistency. Combined with the modification effect of the interface SAM+IL layer, a multi-dimensional defect control system of "bulk defect suppression-interface defect passivation" is formed. This dual-interface synergistic technology combines solution method and evaporation process, offering both material design flexibility and process compatibility, and providing a systematic solution for interface engineering of high-efficiency perovskite solar cells.

[0075] like Figure 3 As shown, the fabrication method of the above-mentioned perovskite solar cell device will be described in detail below. It includes the following steps:

[0076] Step S1: The substrate is ultrasonically cleaned and dried sequentially using acetone, micron-level semiconductor-specific detergent, deionized water, and isopropanol to ensure surface cleanliness.

[0077] Step S2: Prepare an anode layer on the above substrate;

[0078] Step S3: Deposit nickel oxide (NiO) on the above substrate using electron beam evaporation. x () layer, which can selectively be formed between the anode layer and NiO x An anodic buffer layer is formed between the layers, or in NiO x An electron blocking layer and / or an exciton blocking layer are formed on the layer, which together constitute the hole transport layer;

[0079] Step S4: Form a SAM+IL mixed layer on the hole transport layer using a solution method, and regulate NiO. x Surface wettability and defect status;

[0080] Step S5: Form SAM-doped CsPbI on the above SAM+IL mixed layer using solution processing. x Br 3-x The thin film, after annealing, forms a high-quality polycrystalline thin film;

[0081] Step S6: A SAM+IL hybrid layer is formed on the above perovskite layer by solution method to passivate the top interface defects and optimize energy level matching;

[0082] Step S7: C is deposited sequentially on the above SAM+IL hybrid layer using thermal evaporation and atomic layer deposition methods. 60 The perovskite light-absorbing layer and the SnO2 layer can be selectively combined. 60 Hole blocking layers and / or exciton blocking layers are formed between the layers to improve electron extraction efficiency;

[0083] Step S8: A cathode layer is formed on the electron transport layer by vapor deposition. A cathode buffer layer can be selectively formed between the electron transport layer and the cathode layer to improve the interface contact.

[0084] In step S1, the substrate material can be of the following categories:

[0085] Rigid substrates: including glass, quartz, sapphire, etc., possess high hardness, high chemical stability and good surface flatness;

[0086] Flexible substrates: These include polyester materials such as polyimide, polyethylene terephthalate (PET), and polyethylene naphthalate (PEN), which are lightweight and flexible, making them suitable for flexible electronic devices.

[0087] Special material substrates: including metal, alloy and stainless steel thin films, which combine conductivity and mechanical strength to meet specific functional requirements.

[0088] In step S2, the anode layer material mainly includes three types:

[0089] Metallic materials: Aluminum, silver-magnesium alloy, silver, gold, etc. can be selected, which are used as basic electrode materials due to their excellent conductivity;

[0090] Metal oxides: including indium tin oxide (ITO), fluorine-doped tin dioxide (FTO), zinc oxide (ZnO), indium gallium zinc oxide (IGZO) and combinations thereof, which are suitable for optoelectronic devices due to their high transparency and conductivity;

[0091] Organic conductive materials: represented by poly(3,4-ethylenedioxythiophene)-poly(styrene sulfonic acid) (PEDOT / PSS) and its modified products, through chemical modification or composite optimization, meet the hole transport layer requirements of organic electronic devices.

[0092] In step S3, only nickel oxide (NiO) can be formed on the anode layer. x The nickel oxide layer can be used as a hole transport layer; an electron blocking layer and / or an exciton blocking layer can also be formed on the nickel oxide layer. The electron blocking layer and / or exciton blocking layer can block electrons or excitons from flowing into the hole transport layer, thereby reducing the recombination probability of holes and electrons. In this case, the nickel oxide layer and the electron blocking layer and / or exciton blocking layer together serve as the hole transport layer.

[0093] In step S5, C can be deposited on the substrate with the perovskite light-absorbing layer. 60 The layer serves as an electron transport layer. Additionally, in other embodiments, a layer can also be used in C. 60 Below the layer, a hole blocking layer and / or an exciton blocking layer are formed. These layers prevent holes or excitons from flowing into the electron transport layer, thereby reducing the probability of hole-electron recombination. At this point, C... 60 The layer, together with the hole blocking layer and / or exciton blocking layer, serves as an electron transport layer.

[0094] In step S8, the cathode layer material can be of the following categories:

[0095] Metallic materials: Aluminum, silver-magnesium alloy, silver, gold, etc. can be selected. With their excellent conductivity and processing adaptability, they have become the basic materials for cathodes of electronic devices. Among them, precious metals (such as silver and gold) also have good chemical stability and are suitable for high reliability scenarios.

[0096] Metal oxides: including indium tin oxide (ITO), fluorine-doped tin dioxide (FTO), zinc oxide (ZnO), indium gallium zinc oxide (IGZO) and combinations thereof, characterized by high light transmittance and conductivity, are often used in the cathodes of optoelectronic devices that require optical transparency, and their electrical properties can be controlled by multiple components;

[0097] Organic conductive materials, represented by poly(3,4-ethylenedioxythiophene)-poly(styrene sulfonic acid) (PEDOT / PSS) and its modified products, combine solution processability and interfacial compatibility. Through molecular structure modification or composite modification, the charge injection efficiency of the cathode and active layer can be optimized, making them suitable for flexible organic electronic devices.

[0098] In other embodiments, step S2 may further include: preparing an anode buffer layer between the anode layer and the hole transport layer, and promoting efficient hole injection into the anode by adjusting the interface energy level matching. Similarly, step S8 may add a cathode buffer layer preparation process, that is, constructing a functional interface layer between the electron transport layer and the cathode layer to optimize the electron transport path and ensure smooth electron injection into the cathode.

[0099] The specific fabrication steps of the perovskite solar cell device of the present invention will be described in detail below through six embodiments.

[0100] Example 1:

[0101] ITO conductive glass with a sheet resistance of approximately 15 Ω / □ and a thickness of 100 nm was selected as the substrate. It was sequentially ultrasonically cleaned in acetone, semiconductor-grade detergent, deionized water, and isopropanol for 20 minutes each to thoroughly remove surface contaminants, and then dried in an 80°C oven. Nickel oxide (NiO) was deposited on the ITO substrate using electron beam evaporation. x Hole transport layer: with NiO x Using the target material as raw material, thin film growth is achieved by electron beam bombardment. After evaporation, the film is annealed in air at 300°C for 60 minutes to optimize the crystallinity of the film. After multiple experiments, it was found that the device performance is optimal when the hole transport layer thickness is precisely controlled to 30nm.

[0102] A SAM1-doped CsPbI2Br perovskite light-absorbing layer was prepared using a solution method. After film formation, the device was transferred to a thermal evaporation deposition apparatus. When the vacuum level in the deposition chamber decreased to 10... -4 Below Pa, 60 nm thick C layers are sequentially deposited through a mask. 60An electron transport layer and a 10 nm thick SnO2 layer were prepared using atomic layer deposition (ALD). Utilizing the large-area, uniform film formation characteristics of evaporation, battery devices of different sizes can be flexibly fabricated by changing the mask. Finally, Ag metal was deposited as the cathode using thermal evaporation, and the film thickness was monitored in real time using a quartz crystal thickness gauge to ensure it reached a thickness of over 100 nm. The final device structure was: glass / ITO / NiO. x (30nm) / CsPbI2Br+SAM / C 60 (60nm) / SnO2 (10nm) / Ag (100nm).

[0103] After the device was fabricated, the current-voltage characteristic curve was measured using a high-precision current-voltage source meter (such as Keithley 2400). Combined with the light intensity data provided by a standard AM1.5G solar simulator (100mW / cm²), the short-circuit current density (J / cm²) was calculated. sc ), open circuit voltage (V) oc The core performance parameters include fill factor (FF) and power conversion efficiency (PCE). Through systematic analysis of these photovoltaic performance indicators, the device structure is optimized.

[0104] Figure 4 The current density-voltage characteristic curve of the perovskite solar cell device prepared in this embodiment is shown.

[0105] Example 2:

[0106] ITO conductive glass with a sheet resistance of approximately 15 Ω / □ and a thickness of 100 nm was selected as the substrate. It was sequentially ultrasonically cleaned in acetone, semiconductor-grade detergent, deionized water, and isopropanol for 20 minutes each to remove surface contaminants, and then dried in an 80°C oven. Nickel oxide (NiO) was deposited on the ITO substrate using electron beam evaporation. x Hole transport layer: with NiO x Using a target material as raw material, thin film growth is achieved by electron beam bombardment. After evaporation, the film is annealed in air at 300°C for 60 minutes to optimize crystallinity. Through film thickness control experiments, it was determined that a hole transport layer with a thickness of 30 nm can achieve the best device performance.

[0107] In NiO x Preparation of SAM+IL interface modified layer on substrate surface: SAM1 and IL1 were dissolved in anhydrous methanol at a mass ratio of 1:1 to prepare a mixed solution with a concentration of 2 mg / mL. A uniform modified layer was then formed on the substrate surface using a spin-coating process. Subsequently, a SAM1-doped CsPbI2Br perovskite light-absorbing layer was prepared using a solution method. The prepared perovskite film was then transferred to a thermal evaporation equipment, and the vacuum degree of the evaporation chamber was reduced to 10... -4 Below Pa, 60 nm thick C layers are sequentially deposited through a mask.60 An electron transport layer and a 10 nm thick SnO2 layer (prepared by atomic layer deposition) were constructed. Leveraging the uniformity of the evaporation process, devices of different sizes could be flexibly fabricated by changing the mask. Finally, Ag metal was deposited as the cathode, and the cathode thickness was monitored in real-time using a quartz crystal thickness gauge to control the thickness at 100 nm. The final device structure was: glass / ITO / NiO. x (30nm) / SAM+IL / CsPbI2Br+SAM / C 60 (60nm) / SnO2 (10nm) / Ag (100nm)

[0108] After the device was fabricated, a high-precision current and voltage source meter (such as Keithley 2400) was used under standard AM1.5G illumination conditions (100mW / cm²). 2 The current-voltage characteristic curve was measured under the condition that light intensity data was simultaneously acquired to calculate the short-circuit current density (J). sc ), open circuit voltage (V) oc The system optimizes the device structure design by comparing performance parameters under different interface modification conditions, including fill factor (FF) and power conversion efficiency (PCE).

[0109] Figure 5 The current density-voltage characteristic curves of the perovskite solar cell device with the SAM+IL interface modification layer prepared in this embodiment are shown. The test data show that the synergistic modification of SAM and IL significantly reduces the interface defect density and optimizes the energy level matching. The photoelectric performance of the device shows a systematic improvement compared with the unmodified device (Example 1), verifying the effectiveness of the interface modulation strategy.

[0110] Example 3:

[0111] ITO conductive glass with a sheet resistance of approximately 15 Ω / □ and a thickness of 100 nm was selected as the substrate. It was sequentially ultrasonically cleaned in acetone, semiconductor-grade detergent, deionized water, and isopropanol for 20 minutes each to remove surface contaminants, and then dried in an 80°C oven. Nickel oxide (NiO) was deposited on the ITO substrate using electron beam evaporation. x Hole transport layer: with NiO x Using a target material as raw material, thin film growth is achieved by electron beam bombardment. After evaporation, the film is annealed in air at 300°C for 60 minutes to optimize crystallinity. Through film thickness control experiments, it was determined that a hole transport layer with a thickness of 30 nm can achieve the best device performance.

[0112] A SAM1-doped CsPbI₂Br perovskite light-absorbing layer was prepared using a solution method. Then, a SAM+IL interface modification layer was prepared on the perovskite layer surface: SAM1 and IL1 were dissolved in anhydrous methanol at a mass ratio of 1:1 to prepare a mixed solution with a concentration of 2 mg / mL. This solution was then spin-coated onto the substrate surface to form a uniform modification layer. The prepared substrate was subsequently transferred to a thermal evaporation apparatus, and the vacuum level in the evaporation chamber was reduced to 10... -4 Below Pa, 60 nm thick C layers are sequentially deposited through a mask. 60 An electron transport layer and a 10 nm thick SnO2 layer (prepared by atomic layer deposition) were constructed. Leveraging the uniformity of the evaporation process, devices of different sizes could be flexibly fabricated by changing the mask. Finally, Ag metal was deposited as the cathode, and the cathode thickness was monitored in real-time using a quartz crystal thickness gauge to control the thickness at 100 nm. The final device structure was: glass / ITO / NiO. x (30nm) / CsPbI2Br+SAM / SAM+IL / C 60 (60nm) / SnO2 (10nm) / Ag (100nm).

[0113] After the device was fabricated, a high-precision current and voltage source meter (such as Keithley 2400) was used under standard AM1.5G illumination conditions (100mW / cm²). 2 The current-voltage characteristic curve was measured under the condition that light intensity data was simultaneously acquired to calculate the short-circuit current density (J). sc ), open circuit voltage (V) oc The system optimizes the device structure design by comparing performance parameters under different interface modification conditions, including fill factor (FF) and power conversion efficiency (PCE).

[0114] Figure 6 The current density-voltage characteristic curves of the perovskite solar cell device with the SAM+IL interface modification layer prepared in this embodiment are shown. The test data show that the synergistic modification of SAM and IL significantly reduces the interface defect density and optimizes the energy level matching. The photoelectric performance of the device shows a systematic improvement compared with the unmodified device (Example 1), verifying the effectiveness of the interface modulation strategy.

[0115] Example 4:

[0116] ITO conductive glass with a sheet resistance of approximately 15 Ω / □ and a thickness of 100 nm was selected as the substrate. It was sequentially ultrasonically cleaned in acetone, semiconductor-grade detergent, deionized water, and isopropanol for 20 minutes each to remove surface contaminants, and then dried in an 80°C oven. Nickel oxide (NiO) was deposited on the ITO substrate using electron beam evaporation. x Hole transport layer: with NiO xUsing a target material as raw material, thin film growth is achieved by electron beam bombardment. After evaporation, the film is annealed in air at 300°C for 60 minutes to optimize crystallinity. Through film thickness control experiments, it was determined that a hole transport layer with a thickness of 30 nm can achieve the best device performance.

[0117] In NiO x A SAM+IL interface-modified layer was prepared on the substrate surface: SAM1 and IL1 were dissolved in anhydrous methanol at a mass ratio of 0.5:1 to prepare a mixed solution with a concentration of 2 mg / mL. This solution was then spin-coated onto the substrate surface to form a uniform modified layer. A SAM1-doped CsPbI2Br perovskite light-absorbing layer was prepared using a solution method. Then, a SAM+IL interface-modified layer was prepared on the perovskite layer surface: SAM1 and IL1 were dissolved in anhydrous methanol at a mass ratio of 0.5:1 to prepare a mixed solution with a concentration of 2 mg / mL. This solution was then spin-coated onto the substrate surface to form a uniform modified layer. The prepared substrate was then transferred to a thermal evaporation equipment, and the vacuum level in the evaporation chamber was reduced to 10... -4 Below Pa, 60 nm thick C layers are sequentially deposited through a mask. 60 An electron transport layer and a 10 nm thick SnO2 layer (prepared by atomic layer deposition) were constructed. Leveraging the uniformity of the evaporation process, devices of different sizes could be flexibly fabricated by changing the mask. Finally, Ag metal was deposited as the cathode, and the cathode thickness was monitored in real-time using a quartz crystal thickness gauge to control the thickness at 100 nm. The final device structure was: glass / ITO / NiO. x (30nm) / SAM+IL / CsPbI2Br+SAM / SAM+IL / C 60 (60nm) / SnO2 (10nm) / Ag (100nm)

[0118] After the device was fabricated, a high-precision current and voltage source meter (such as Keithley 2400) was used under standard AM1.5G illumination conditions (100mW / cm²). 2 The current-voltage characteristic curve was measured under the condition that light intensity data was simultaneously acquired to calculate the short-circuit current density (J). sc ), open circuit voltage (V) oc The system optimizes the device structure design by comparing performance parameters under different interface modification conditions, including fill factor (FF) and power conversion efficiency (PCE).

[0119] Figure 7 The current density-voltage characteristic curves of the perovskite solar cell device with the SAM+IL interface modification layer prepared in this embodiment are shown. The test data show that the synergistic modification of SAM and IL significantly reduces the interface defect density and optimizes the energy level matching. The photoelectric performance of the device shows a systematic improvement compared with the unmodified device (Example 1), verifying the effectiveness of the interface modulation strategy.

[0120] Example 5:

[0121] ITO conductive glass with a sheet resistance of approximately 15 Ω / □ and a thickness of 100 nm was selected as the substrate. It was sequentially ultrasonically cleaned in acetone, semiconductor-grade detergent, deionized water, and isopropanol for 20 minutes each to remove surface contaminants, and then dried in an 80°C oven. Nickel oxide (NiO) was deposited on the ITO substrate using electron beam evaporation. x Hole transport layer: with NiO x Using a target material as raw material, thin film growth is achieved by electron beam bombardment. After evaporation, the film is annealed in air at 300°C for 60 minutes to optimize crystallinity. Through film thickness control experiments, it was determined that a hole transport layer with a thickness of 30 nm can achieve the best device performance.

[0122] In NiO x A SAM+IL interface-modified layer was prepared on the substrate surface: SAM1 and IL1 were dissolved in anhydrous methanol at a mass ratio of 1:1 to prepare a mixed solution with a concentration of 2 mg / mL. This solution was then spin-coated to form a uniform modified layer on the substrate surface. A SAM1-doped CsPbI2Br perovskite light-absorbing layer was prepared using a solution method. Then, a SAM+IL interface-modified layer was prepared on the perovskite layer surface: SAM1 and IL1 were dissolved in anhydrous methanol at a mass ratio of 1:1 to prepare a mixed solution with a concentration of 2 mg / mL. This solution was then spin-coated to form a uniform modified layer on the substrate surface. The prepared substrate was then transferred to a thermal evaporation equipment, and the vacuum level in the evaporation chamber was reduced to 10... -4 Below Pa, 60 nm thick C layers are sequentially deposited through a mask. 60 An electron transport layer and a 10 nm thick SnO2 layer (prepared by atomic layer deposition) were constructed. Leveraging the uniformity of the evaporation process, devices of different sizes could be flexibly fabricated by changing the mask. Finally, Ag metal was deposited as the cathode, and the cathode thickness was monitored in real-time using a quartz crystal thickness gauge to control the thickness at 100 nm. The final device structure was: glass / ITO / NiO. x (30nm) / SAM+IL / CsPbI2Br+SAM / SAM+IL / C 60 (60nm) / SnO2 (10nm) / Ag (100nm)

[0123] After the device was fabricated, a high-precision current and voltage source meter (such as Keithley 2400) was used under standard AM1.5G illumination conditions (100mW / cm²). 2 The current-voltage characteristic curve was measured under the condition that light intensity data was simultaneously acquired to calculate the short-circuit current density (J). sc ), open circuit voltage (V) oc The system optimizes the device structure design by comparing performance parameters under different interface modification conditions, including fill factor (FF) and power conversion efficiency (PCE).

[0124] Figure 8 The current density-voltage characteristic curves of the perovskite solar cell device with the SAM+IL interface modification layer prepared in this embodiment are shown. The test data show that the synergistic modification of SAM and IL significantly reduces the interface defect density and optimizes the energy level matching. The photoelectric performance of the device shows a systematic improvement compared with the unmodified device (Example 1), verifying the effectiveness of the interface modulation strategy.

[0125] Example 6:

[0126] ITO conductive glass with a sheet resistance of approximately 15 Ω / □ and a thickness of 100 nm was selected as the substrate. It was sequentially ultrasonically cleaned in acetone, semiconductor-grade detergent, deionized water, and isopropanol for 20 minutes each to remove surface contaminants, and then dried in an 80°C oven. Nickel oxide (NiO) was deposited on the ITO substrate using electron beam evaporation. x Hole transport layer: with NiO x Using a target material as raw material, thin film growth is achieved by electron beam bombardment. After evaporation, the film is annealed in air at 300°C for 60 minutes to optimize crystallinity. Through film thickness control experiments, it was determined that a hole transport layer with a thickness of 30 nm can achieve the best device performance.

[0127] In NiO x A SAM+IL interface-modified layer was prepared on the substrate surface: SAM1 and IL1 were dissolved in anhydrous methanol at a mass ratio of 2:1 to prepare a mixed solution with a concentration of 2 mg / mL. This solution was then spin-coated to form a uniform modified layer on the substrate surface. A SAM1-doped CsPbI2Br perovskite light-absorbing layer was prepared using a solution method. Then, a SAM+IL interface-modified layer was prepared on the perovskite layer surface: SAM1 and IL1 were dissolved in anhydrous methanol at a mass ratio of 2:1 to prepare a mixed solution with a concentration of 2 mg / mL. This solution was then spin-coated to form a uniform modified layer on the substrate surface. The prepared substrate was then transferred to a thermal evaporation equipment, and the vacuum level in the evaporation chamber was reduced to 10... -4 Below Pa, 60 nm thick C layers are sequentially deposited through a mask. 60 An electron transport layer and a 10 nm thick SnO2 layer (prepared by atomic layer deposition) were constructed. Leveraging the uniformity of the evaporation process, devices of different sizes could be flexibly fabricated by changing the mask. Finally, Ag metal was deposited as the cathode, and the cathode thickness was monitored in real-time using a quartz crystal thickness gauge to control the thickness at 100 nm. The final device structure was: glass / ITO / NiO. x (30nm) / SAM+IL / CsPbI2Br+SAM / SAM+IL / C 60 (60nm) / SnO2 (10nm) / Ag (100nm)

[0128] After the device was fabricated, a high-precision current and voltage source meter (such as Keithley 2400) was used under standard AM1.5G illumination conditions (100mW / cm²). 2 The current-voltage characteristic curve was measured under the condition that light intensity data was simultaneously acquired to calculate the short-circuit current density (J). sc ), open circuit voltage (V) oc The system optimizes the device structure design by comparing performance parameters under different interface modification conditions, including fill factor (FF) and power conversion efficiency (PCE).

[0129] Figure 9 The current density-voltage characteristic curves of the perovskite solar cell device with the SAM+IL interface modification layer prepared in this embodiment are shown. The test data show that the synergistic modification of SAM and IL significantly reduces the interface defect density and optimizes the energy level matching. The photoelectric performance of the device shows a systematic improvement compared with the unmodified device (Example 1), verifying the effectiveness of the interface modulation strategy.

[0130] The table below summarizes the photovoltaic performance parameters of the perovskite solar cell devices in the six embodiments:

[0131]

[0132] Example 1: Without SAM+IL interface modification, the open-circuit voltage is only 0.97V, the lowest among all examples. This means that under no-light conditions, the potential difference maintained across the battery is extremely small, directly affecting the basic conditions for subsequent power generation. The fill factor is 72.42%, also the lowest among all examples, indicating that the battery's energy collection and utilization efficiency is poor in actual operation, with significant room for improvement. The short-circuit current is 15.26mA / cm. 2 The low level reflects the relatively limited maximum current intensity that the battery can generate under illumination. Ultimately, the solar energy conversion efficiency was only 10.72%, the lowest among all embodiments, which fully demonstrates the battery's weak ability to convert received solar energy into electrical energy. In summary, all indicators are at the lowest levels, clearly indicating that without special interface optimization and other treatments, the device's photoelectric performance has significant limitations, making it difficult to achieve efficient photoelectric conversion.

[0133] Examples 2-3: After modifying the lower and upper interfaces with SAM+IL, the open-circuit voltage significantly increased to 1.11V, a marked improvement compared to Example 1. This allows the battery to maintain a higher potential difference in the absence of light, creating more favorable conditions for subsequent energy generation. The fill factors reached 77.13% and 77.37% respectively, a significant improvement over 72.42% in Example 1, indicating enhanced energy collection and utilization efficiency and more effective output of generated energy. The short-circuit current increased to 16.25mA / cm. 2 16.18 mA / cm 2 This is higher than the 15.26 mA / cm in Example 1. 2 This indicates that the battery can generate a stronger current under illumination. The solar energy conversion efficiency increased to 13.91% and 13.80%, a significant improvement compared to Example 1. These data changes fully demonstrate that SAM+IL optimizes the interface performance of the battery, effectively improving the overall photoelectric performance by improving processes such as charge transport, thus verifying the positive impact of interface modification technology on battery performance improvement.

[0134] Examples 4-6: Simultaneous introduction of SAM+IL interface modification and adjustment of its ratio further refined and improved battery performance. Taking Example 4 as an example, the open-circuit voltage reached 1.13V, a significant improvement compared to the unmodified Example 1. This means that the battery's ability to maintain a potential difference under no-light conditions is greatly enhanced, providing a more solid potential foundation for photoelectric conversion. The fill factor was 81.94%, indicating a significant improvement in the battery's energy collection and utilization efficiency, enabling more efficient integration and output of the generated energy. The short-circuit current was 16.29mA / cm. 2 Compared to 15.26 mA / cm in Example 1 2 The significant increase reflects a further improvement in the battery's ability to generate current under illumination; the solar energy conversion efficiency reached 15.08%, which is significantly higher than that of Examples 1-3, demonstrating the initial synergistic effect of interface modification and ratio control.

[0135] In Example 5, the open-circuit voltage reached 1.17V, the highest among all examples. This ensured that the battery maintained an optimal potential difference in the absence of light, providing excellent potential conditions for the subsequent photoelectric process. The fill factor was as high as 84%, the highest among all examples, indicating that the battery's energy collection and utilization efficiency was nearly ideal, enabling efficient output of the energy generated by photoelectric conversion. The short-circuit current was 16.33mA / cm. 2 The continuous growth trend further demonstrates the enhanced ability of the battery to generate current under sunlight; the solar energy conversion efficiency reached 16.05%, the highest among all embodiments, marking a qualitative leap in the battery's ability to convert solar energy into electrical energy.

[0136] The open-circuit voltage of Example 6 is 1.15V, which remains at a high level, ensuring the potential difference advantage of the battery in the absence of light; the fill factor is 80.65%, which is slightly lower than that of Example 5, but still significantly improved compared to the unmodified Example 1, indicating better energy harvesting and utilization efficiency; the short-circuit current is 16.27mA / cm. 2 The battery maintained a high current output level; its solar energy conversion efficiency was 15.09%, significantly higher than that of the unmodified embodiment. At a deeper mechanistic level, this synergistic effect is not only a numerical breakthrough but also reshapes the carrier behavior within the battery at the level of charge dynamics.

[0137] In summary, the SAM+IL interface modification technology and the SAM doping strategy of the perovskite layer play a crucial role in improving the performance of perovskite solar cells. Especially when the two are applied synergistically, they exhibit a significant synergistic coupling effect, achieving breakthroughs in core parameters such as open-circuit voltage, short-circuit current, and fill factor. A deeper analysis of the interface mechanism reveals that the bottom interface SAM+IL layer (NiO... x In / CsPbI2Br), the phosphonic acid group of the SAM molecule interacts with the Pb at the perovskite substrate interface. 2+ Defect-specific binding occurs when the cations and anions of IL form coordination bonds with halogen vacancies, synergistically passivating interface defects and simultaneously modulating NiO. x The energy level shift between the valence band top and the perovskite valence band edge promotes efficient hole injection; in the top interface SAM+IL layer (CsPbI2Br / electron transport layer), SAM molecules passivate uncoordinated Pb on the perovskite surface. 2+ IL improves interfacial wettability and inhibits ion migration, optimizes the matching degree between the perovskite conduction band bottom and the electron transport layer conduction band energy level, and enhances electron injection efficiency. Regarding the synergistic enhancement mechanism, in terms of defect passivation, SAM specifically captures Pb. 2+ To address defects, the interfacial layer (IL) covers halogen vacancies and suppresses ion migration, thus reducing interface defect density and extending carrier lifetime. In terms of energy level regulation, SAM molecular groups, combined with the IL dipole moment, modulate interface energy levels, constructing an ideal energy level alignment structure. Regarding carrier transport, dual-interface modification shortens transport paths and reduces charge accumulation. In terms of materials and processes, SAM doping suppresses grain boundary defects in CsPbI2Br films, improving crystal orientation consistency. Combined with interface SAM+IL layer modification, a comprehensive defect regulation system of "bulk defect suppression - interface defect passivation" is formed. Furthermore, the combination of solution-based and vapor deposition processes offers both material design flexibility and process compatibility. This synergistic optimization provides a highly promising technical path for perovskite solar cells to move towards industrial application, achieving comprehensive performance improvement and mechanism innovation from multiple dimensions.

[0138] In an alternative implementation:

[0139] Optimization of blocking and buffer layers: The hole transport layer may include an electron blocking layer or an exciton blocking layer, and the electron transport layer may include a hole blocking layer or an exciton blocking layer. A buffer layer may be set between the anode / cathode layer and the transport layer to further improve interface stability and carrier transport efficiency.

[0140] Material compatibility: The anode and cathode layers can be made of various metals, metal oxides or conductive polymers to suit different substrates and device structure requirements; at the same time, the types and ratios of SAM and IL can be adjusted according to actual needs to optimize the synergistic modification effect.

[0141] Through the above technical solutions, this invention provides novel materials and preparation methods for interface engineering of perovskite solar cells, effectively solving the efficiency and stability bottlenecks of traditional devices, and has significant scientific and industrial value.

[0142] The above description is merely a preferred embodiment of the present invention. It should be understood that the present invention is not limited to the forms disclosed herein and should not be construed as excluding other embodiments. It can be used in various other combinations, modifications, and environments, and can be altered within the scope of the concept described herein through the above teachings or related technologies or knowledge. Modifications and variations made by those skilled in the art that do not depart from the spirit and scope of the present invention should be within the protection scope of the appended claims.

Claims

1. A perovskite photovoltaic cell device, characterized in that: The perovskite solar cell device includes a substrate, an anode layer, a hole transport layer, a perovskite + SAM light absorption layer, a SAM + IL layer, an electron transport layer, and a cathode layer, which are stacked sequentially from bottom to top. The SAM absorber layer comprises CsPbI. x Br 3-x The electron transport layer is doped with SAM, where x = 2~3, and includes a nickel oxide layer deposited by electron beam evaporation. The electron transport layer comprises fullerene C layers stacked sequentially from bottom to top. 60 Layer with SnO2, the C 60 The SAM layer and SnO2 layer were obtained by thermal evaporation and atomic layer deposition, respectively. The SAM molecules bind to perovskite defects through functional anchoring groups to achieve defect passivation, and the interface energy level matching is optimized by molecular electron-donating / withdrawing units and dipole moment regulation.

2. The perovskite photovoltaic cell device according to claim 1, characterized in that: The hole transport layer further includes an electron blocking layer and / or an exciton blocking layer; the electron transport layer further includes a hole blocking layer and / or an exciton blocking layer; an anode buffer layer is further included between the anode layer and the hole transport layer; and a cathode buffer layer is further included between the cathode layer and the electron transport layer.

3. A method for fabricating a perovskite solar cell device, characterized in that, The main steps include the following: Step S1. Obtain the substrate and ultrasonically clean it sequentially using acetone, micron-level semiconductor-specific detergent, deionized water, and isopropanol, then dry it. Step S2. Prepare an anode layer on the substrate; Step S3. A nickel oxide layer is deposited on the anode layer using electron beam evaporation to serve as a hole transport layer; Step S4. Deposit a hybrid SAM and IL layer on the hole transport layer; Step S5. Deposit components including CsPbI on the SAM and IL mixed layer. x Br 3-x A perovskite light-absorbing layer doped with SAM, where x = 2~3; Step S6. Deposit a mixed film of SAM and IL on the perovskite light-absorbing layer; Step S7. Fullerene C is sequentially deposited on the SAM and IL mixed film using thermal evaporation and atomic layer deposition. 60 The layer consists of a SnO2 layer and an electron transport layer. Step S8. Prepare a cathode layer on the electron transport layer.

4. The preparation method according to claim 3, characterized in that: The anode layer and the cathode layer are metals or metal oxides or poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonic acid) and their modified products; wherein the metal is aluminum, silver-magnesium alloy, silver or gold; and the metal oxide is one or more of indium tin oxide, fluorine-doped tin dioxide, zinc oxide and indium gallium zinc oxide.

5. The preparation method according to claim 3, characterized in that, Step S3 further includes: forming an anode buffer layer between the anode layer and the hole transport layer.

6. The preparation method according to claim 3, characterized in that, Step S3 further includes: forming an electron blocking layer and / or an exciton blocking layer on the nickel oxide layer; wherein the nickel oxide layer and the electron blocking layer and / or exciton blocking layer together serve as the hole transport layer.

7. The preparation method according to claim 3, characterized in that, Step S7 further includes: forming a hole blocking layer and / or an exciton blocking layer on the perovskite light-absorbing layer, wherein the fullerene C 60 The SnO2 layer, the hole blocking layer, and / or the exciton blocking layer together serve as the electron transport layer.

8. The preparation method according to claim 3, characterized in that, Step S8 further includes: forming a cathode buffer layer between the electron transport layer and the cathode layer.

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