Flexible perovskite photovoltaic module, preparation method thereof and embedded flexible photovoltaic module anti-dazzle packaging vehicle rearview mirror

Abstract

This invention provides a flexible perovskite photovoltaic module, its fabrication method, and an embedded flexible photovoltaic module anti-glare encapsulated automotive rearview mirror. It relates to the technical field of photovoltaic technology applied to automotive equipment. The conductive substrate flexible perovskite photovoltaic module includes a perovskite thin film layer containing additives; wherein 4-(2-pyridinylthio)benzonitrile is introduced as an additive into the perovskite precursor to form the perovskite thin film layer. This invention innovatively introduces novel molecular additives with multi-site coordination / strong dipole properties into the perovskite precursor solution, which can simultaneously regulate the perovskite nucleation and crystallization process, passivate bulk phase and grain boundary defects, inhibit ion migration, and significantly reduce the density of bulk phase and grain boundary defects. Ultimately, while ensuring process repeatability, it further improves the energy conversion efficiency and long-term stability of the flexible perovskite photovoltaic device.

Description

Technical Field

[0001] This invention relates to the technical field of photovoltaic technology applied to vehicle equipment, and in particular to a flexible perovskite photovoltaic module and its preparation method, and an embedded flexible photovoltaic module anti-glare encapsulated vehicle rearview mirror. Background Technology

[0002] As a core optical auxiliary component of automobiles, the rearview mirror's auxiliary electrical components rely on the vehicle's power supply. Flexible perovskite photovoltaic modules possess advantages such as high energy conversion efficiency, thinness and flexibility, low manufacturing cost, and strong process compatibility, theoretically meeting the needs of automotive applications. Currently, the defects and non-radiative recombination of perovskite thin films remain the core bottlenecks restricting efficiency stability and long-term service reliability. Existing research generally employs strategies such as low-dimensional perovskite passivation and interface / surface passivation to improve device performance by reducing grain boundary and surface trap density. However, existing additives are mostly concentrated on low-dimensional perovskite surface passivation or Lewis base molecules with single coordination sites, focusing more on interface / surface defect suppression, making it difficult to simultaneously achieve a balance between bulk crystallization control, grain boundary defect passivation, and ion migration suppression. Furthermore, some existing additives suffer from problems such as difficulty in matching coordination strength, narrow effective doping windows, easy residue formation of insulating phases, or migration and volatilization under humid heat, resulting in insufficient thin film crystallization consistency and defect passivation durability, thus limiting the repeatability and long-term stability of device efficiency improvements. Summary of the Invention

[0003] One of the objectives of this invention is to provide a flexible perovskite photovoltaic module to at least solve one of the technical problems existing in the prior art.

[0004] The second objective of this invention is to provide a method for preparing a flexible perovskite photovoltaic module.

[0005] The third objective of this invention is to provide an embedded flexible photovoltaic module anti-glare encapsulated vehicle rearview mirror.

[0006] In order to achieve the above-mentioned objectives of the present invention, the following technical solution is adopted: In a first aspect, the present invention provides a flexible perovskite photovoltaic module, comprising: a hole transport layer, a perovskite thin film layer containing additives, a passivation layer, an electron transport layer and electrodes sequentially stacked on a conductive substrate; In this process, 4-(2-pyridinylthio)benzonitrile is introduced as an additive into the perovskite precursor to form a perovskite thin film layer.

[0007] Furthermore, the concentration of 4-(2-pyridinylthio)benzonitrile in the perovskite precursor is 0.3-0.8 mg / ml; Preferably, the thickness of the hole transport layer is 1-50 nm; Preferably, the thickness of the perovskite thin film layer containing additives is 100-1000 nm; Preferably, the thickness of the passivation layer is 1-50 nm; Preferably, the electron transport layer comprises C layers stacked sequentially. 60 Layer and BCP layer; the C 60 The thickness of the layer is 1-1000 nm; the thickness of the BCP layer is 1-1000 nm; Preferably, the electrode includes one or more of Au electrode, Ag electrode and carbon electrode; Preferably, the thickness of the electrode is 200-400 nm.

[0008] Secondly, the present invention provides a method for preparing a flexible perovskite photovoltaic module, comprising the following steps: A hole transport layer, an additive-containing perovskite thin film layer, a passivation layer, an electron transport layer, and an electrode are sequentially stacked on a conductive substrate to obtain the flexible perovskite photovoltaic module.

[0009] Furthermore, after the hole transport layer is formed by spin coating, deposition, immersion or scraping, it is annealed at a temperature of 80-120°C for 5-10 minutes.

[0010] Furthermore, after the perovskite thin film layer containing additives is formed by spin coating, deposition, immersion or blade coating, it is annealed at a temperature of 90-110°C for 25-35 min. Preferably, the perovskite precursor solution used to prepare the additive-containing perovskite thin film layer includes FA. 0.95 Cs 0.05 The concentration of the perovskite precursor solution is 1.3-1.6 M.

[0011] Furthermore, after the passivation layer is spin-coated or vapor-deposited into a film, it is annealed at a temperature of 80-120°C for 3-8 minutes.

[0012] Furthermore, the electron transport layer is prepared by vapor deposition.

[0013] Furthermore, the electrode is prepared by vapor deposition or printing.

[0014] Thirdly, the present invention provides an embedded flexible photovoltaic module anti-glare encapsulated vehicle rearview mirror, comprising: The rearview mirror housing has a mounting position in its non-field-of-view area for accommodating the flexible perovskite photovoltaic module or the flexible perovskite photovoltaic module prepared by the preparation method described above.

[0015] Furthermore, it also includes an anti-glare and anti-reflective film disposed on the side of the flexible perovskite photovoltaic module facing the external environment.

[0016] Compared with the prior art, the present invention has the following beneficial effects: The flexible perovskite photovoltaic module provided by this invention forms a perovskite thin film layer by introducing 4-(2-pyridinethio)benzonitrile as an additive into the perovskite precursor. 4-(2-pyridinethio)benzonitrile has both the multi-site coordination ability of pyridine N / thioether S and the strong dipole group of nitrile (-CN), which can simultaneously achieve crystallization regulation, defect passivation and ion migration suppression. This overcomes the shortcomings of existing additives in terms of coordination strength matching, effective doping window, insulation phase residue and migration and volatilization under humid and hot conditions, improves the crystallization uniformity and defect passivation durability of the perovskite thin film, and thus improves the energy conversion efficiency and long-term service reliability of the flexible perovskite photovoltaic module. Attached Figure Description

[0017] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram showing the location of the flexible perovskite photovoltaic module provided by the present invention; Figure 2 A schematic diagram illustrating the effect of anti-glare encapsulation of embedded flexible photovoltaic modules in a vehicle rearview mirror; Figure 3 Structural framework diagram of an embedded flexible photovoltaic module anti-glare encapsulation vehicle rearview mirror system; Figure 4 The structural diagram of 4-(2-pyridinylthio)benzonitrile; Figure 5 JV curves for Comparative Example 1 and Example 2; Figure 6 SEM images of Comparative Example 1 and Example 2; Figure 7 The PL curves are for Comparative Example 1 and Example 2. Detailed Implementation

[0019] Unless otherwise defined herein, the scientific and technical terms used in conjunction with this invention shall have the meanings commonly understood by one of ordinary skill in the art. The meaning and scope of terms shall be clear; however, in any case of potential ambiguity, the definitions provided herein shall prevail over any dictionary or foreign definitions. In this application, unless otherwise stated, the use of "or" means "and / or". Furthermore, the use of the term "comprising" and other forms is non-limiting.

[0020] The nomenclature used in analytical chemistry, synthetic organic chemistry, and medical and medicinal chemistry, along with their laboratory procedures and techniques, as described herein, are those well-known and commonly used in the field.

[0021] 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.

[0022] The first aspect of the present invention provides a flexible perovskite photovoltaic module, specifically a perovskite solar cell, comprising: a hole transport layer, an additive-containing perovskite thin film layer, a passivation layer, an electron transport layer, and an electrode sequentially stacked on a conductive substrate; wherein, 4-(2-pyridinylthio)benzonitrile is introduced as an additive into the perovskite precursor to form the perovskite thin film layer.

[0023] This invention innovatively introduces a novel molecular additive with multi-site coordination / strong dipole properties into the perovskite precursor solution, which can simultaneously regulate the perovskite nucleation and crystallization process, passivate bulk phase and grain boundary defects, inhibit ion migration, and significantly reduce the density of bulk phase and grain boundary defects. Ultimately, while ensuring process repeatability, it further improves the energy conversion efficiency and long-term stability of flexible perovskite photovoltaic devices.

[0024] The molecular additive is 4-(2-pyridinylthio)benzonitrile, with the structure as follows: Figure 4 As shown, a molecular additive with pyridine N / thioether S multi-site coordination ability and a strong nitrile (-CN) dipole group is introduced into the perovskite precursor solution to form a reversible coordination intermediate with PbX2, thereby regulating nucleation and crystallization and passivating uncoordinated Pb. 2+ / Grain boundary defects, thereby obtaining perovskite films with larger grains, lower defects, and better stability.

[0025] In some preferred embodiments, the concentration of 4-(2-pyridinylthio)benzonitrile in the perovskite precursor is 0.3-0.8 mg / ml, for example, it can be 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, etc.

[0026] Preferably, the conductive substrate is TCO conductive glass.

[0027] Preferably, the thickness of the hole transport layer is 1-50 nm, for example, it can be 1 nm, 5 nm, 10 nm, 20 nm, 30 nm, 40 nm, 50 nm, etc.

[0028] Preferably, the thickness of the perovskite thin film layer containing additives is 100-1000 nm, for example, it can be 100 nm, 200 nm, 300 nm, 400 nm, 500 nm, 600 nm, 700 nm, 800 nm, 900 nm, 1000 nm, etc.

[0029] Preferably, the thickness of the passivation layer is 1-50 nm, for example, it can be 1 nm, 5 nm, 10 nm, 20 nm, 30 nm, 40 nm, 50 nm, etc.

[0030] Preferably, the electron transport layer comprises C layers stacked sequentially. 60 Layer and BCP layer; the C 60 The thickness of the layer is 1-1000 nm, for example, it can be 1 nm, 5 nm, 10 nm, 100 nm, 500 nm, 1000 nm, etc., and more preferably 5-50 nm; the thickness of the BCP layer is 1-1000 nm, for example, it can be 1 nm, 5 nm, 10 nm, 100 nm, 500 nm, 1000 nm, etc., and more preferably 1-20 nm.

[0031] Preferably, the electrode includes one or more of Au, Ag, and carbon electrodes.

[0032] Preferably, the thickness of the electrode is 200-400 nm.

[0033] A second aspect of this invention provides a method for preparing a flexible perovskite photovoltaic module, comprising the following steps: A hole transport layer, an additive-containing perovskite thin film layer, a passivation layer, an electron transport layer, and an electrode are sequentially stacked on a conductive substrate.

[0034] In some preferred embodiments, after the hole transport layer is formed by spin coating, deposition, immersion or scraping, it is annealed at a temperature of 80-120℃ (e.g., 80℃, 90℃, 100℃, 110℃, 120℃, etc.) for 5-10 minutes, for example, 5 minutes, 7.5 minutes, 10 minutes, etc.

[0035] In some preferred embodiments, the perovskite thin film layer containing additives is formed by spin coating, deposition, immersion or blade coating, and then annealed at a temperature of 90-110°C (e.g., 90°C, 100°C, 110°C, etc.) for 25-35 min, for example, 25 min, 30 min, 35 min, etc.

[0036] Preferably, the perovskite precursor solution used to prepare the additive-containing perovskite thin film layer includes FA. 0.95 Cs 0.05 The concentration of the PbI3 perovskite precursor solution is 1.3-1.6 M, for example, it can be 1.3 M, 1.4 M, 1.5 M, 1.6 M, etc.

[0037] In some preferred embodiments, after the passivation layer is spin-coated or vapor-deposited, it is annealed at a temperature of 80-120°C (e.g., 80°C, 90°C, 100°C, 110°C, 120°C, etc.) for 3-8 minutes, for example, 3 minutes, 5.5 minutes, 8 minutes, etc. The passivation layer can further improve the stability of the film.

[0038] In some preferred embodiments, the electron transport layer is prepared by vapor deposition.

[0039] In some preferred embodiments, the electrode is prepared by vapor deposition or printing.

[0040] In some preferred embodiments, the preparation method further includes ultrasonic cleaning of the conductive substrate followed by ozone treatment.

[0041] At the structural design level of rearview mirrors and photovoltaic modules, existing solutions mostly use additional methods such as bonding and adhesive to fix flexible solar cells to the outer surface of the rearview mirror housing or outer cover. The rearview mirror body structure is not designed with photovoltaic integration in mind, and usually lacks reserved mounting positions, limiting support structures, and reliable structural interfaces to accommodate the battery module. As a result, the photovoltaic module mainly relies on the adhesive layer for support and fixation. Under long-term vehicle driving conditions, the rearview mirror area is continuously subjected to vibration, impact, wind load, and thermal expansion and contraction. The adhesive interface is prone to fatigue aging, edge lifting, local delamination, and even detachment, making it difficult to guarantee the reliability and safety of the module. This is especially true for thin and flexible perovskite modules, which are more susceptible to mechanical stress and failure risks. Furthermore, in terms of environmental protection and durability reliability, external integration exposes photovoltaic modules to complex automotive environments such as rain and snow erosion, humidity and heat changes, ultraviolet aging, and dust and gravel erosion for extended periods. Water seepage channels or weak points in the encapsulation are more likely to form at the bonding edges and interfaces, leading to device moisture absorption, performance degradation, and shortened lifespan. For flexible perovskite devices that are more sensitive to water and oxygen, existing bonding / adhesion-based integration methods cannot simultaneously meet key indicators such as long-term sealing protection, structural stability, and optical safety.

[0042] In view of this, a third aspect of the present invention provides an embedded flexible photovoltaic module anti-glare encapsulated vehicle rearview mirror, comprising: a rearview mirror housing, wherein a mounting position for accommodating the flexible perovskite photovoltaic module or the flexible perovskite photovoltaic module prepared by the aforementioned preparation method is provided in the non-field-of-view area of ​​the rearview mirror housing.

[0043] The embedded flexible photovoltaic module anti-glare encapsulated vehicle rearview mirror provided by this invention brings the photovoltaic integration requirement forward to the rearview mirror body structure design stage. By pre-forming the installation position and structural interface of flexible solar cells in the photovoltaic integration area of ​​the rearview mirror shell / outer cover, the photovoltaic module is transformed from the traditional surface bonding and adhesive attachment installation to an integrated embedded installation that works in synergy with the mirror body structure. This provides a foundation for long-term vibration resistance, stable fixation and external protection at the structural level, and avoids conflicts between the photovoltaic module and the appearance and function of the rearview mirror.

[0044] In some preferred embodiments, the embedded flexible photovoltaic module anti-glare encapsulated vehicle rearview mirror further includes: an anti-glare and anti-reflective film disposed on the side of the flexible perovskite photovoltaic module facing the external environment. The anti-glare glass has optical properties that reduce reflection / suppress glare while maintaining high light transmittance, so as to reduce glare from photovoltaic surface reflection and take into account power generation efficiency. This reduces the risk of glare caused by surface reflection while meeting the photovoltaic incident light requirements. The sealing and encapsulation of the cover plate and the mirror housing enhances weather resistance, forming a scratch-resistant, impact-resistant, waterproof, and dustproof weather-resistant encapsulation for the module, ultimately achieving stable fixation and optical safety under long-term vibration conditions.

[0045] Specifically, the anti-glare and anti-reflective film can be set as an anti-glare glass cover.

[0046] Specifically, the rearview mirror housing has a pre-fabricated receiving cavity / groove at a corresponding position on its outer surface. The flexible perovskite solar cell module is embedded in the receiving cavity and forms a positioning, limiting, and load-bearing cooperation with the housing. The electrical connection terminal is led out through the wiring channel inside the housing and is sealed and protected. An anti-glare glass cover is set on the outside of the flexible solar cell module for covering and encapsulation. The anti-glare glass has the function of reducing reflection / suppressing glare and ensuring light transmittance, so that incident light can effectively enter the photovoltaic module, while reducing the risk of glare caused by mirror reflection on the module surface. Through the combination of integrated embedding and fixing with reserved installation position and anti-glare glass encapsulation, the structural reliability and encapsulation durability of the flexible perovskite module under long-term vibration, impact, and temperature cycling conditions in the vehicle, the failure modes such as edge lifting, delamination, and detachment are improved.

[0047] More preferably, the rearview mirror may have an energy management and output circuit installed inside the housing or in conjunction with it to regulate the output of the flexible solar cell. It may also be equipped with maximum power point tracking, charge and discharge management, energy storage unit and load power supply interface to realize functions such as power supply to the rearview mirror's auxiliary electrical components or vehicle-mounted low-power devices, replenishment of the vehicle's energy storage unit or emergency power output. The structure and circuit are specially designed around the reliability requirements of integrated embedded integration and anti-glare glass encapsulation, so as to achieve a synergistic balance of vibration resistance, durability and anti-glare safety without reducing the original safety and appearance consistency of the rearview mirror.

[0048] This invention integrates and fixes the position of flexible solar cells in the rearview mirror body through a multi-layer composite structure, and encapsulates them with anti-glare glass that has anti-reflection and anti-glare properties while ensuring light transmittance. This achieves stable collaboration between the photovoltaic module and the rearview mirror structure and long-term vibration-resistant and reliable fixation, while reducing the risk of reflection glare and taking into account optical safety and power generation requirements, thereby improving the overall durability and engineering application feasibility in the vehicle environment.

[0049] Compared to existing methods that use bonding or adhesive to fix flexible photovoltaic modules to the outer surface of rearview mirrors, this invention achieves embedded, integrated fixation by pre-setting mounting positions that match the flexible perovskite solar cells within the rearview mirror's main structure. This transforms the photovoltaic module from an adhesive layer into a structural support provided by the mirror structure for positioning, limiting, and support, significantly improving the module's connection reliability and resistance to detachment under long-term vehicle vibration, impact, and temperature cycling conditions, reducing the risk of edge warping, delamination, and failure. Simultaneously, this invention uses anti-glare glass with anti-reflective and anti-glare properties while ensuring light transmittance to cover and encapsulate the photovoltaic module. This effectively reduces the risk of glare caused by mirror reflection on the module surface while meeting the photovoltaic incident light requirements, improving driving optical safety. Furthermore, the integrated interface between the cover and the structure reduces edge water seepage and external erosion channels, enhancing protection against external environmental factors such as rain, snow, humidity, heat, and particle erosion. Ultimately, this achieves long-term stable operation of the photovoltaic module and improves the feasibility of engineering applications without affecting the rearview mirror's appearance and existing functions.

[0050] Furthermore, this invention is applicable to various external rearview components of mobile vehicles and their derivative product forms, including but not limited to passenger car external rearview mirrors, truck / bus wide-angle rearview mirrors, RV external rearview mirrors, motorcycle rearview mirrors, and engineering machinery reversing auxiliary mirrors, etc., which require long-term vibration resistance and outdoor weather resistance. At the same time, it can be used in vehicle-mounted photovoltaic integrated products with high requirements for appearance consistency and driving safety, such as external energy replenishment components with photovoltaic integrated appearance parts and those that need to suppress glare. By encapsulating the top anti-glare glass and fixing it in an integrated structure, the reliability, safety and engineering feasibility in real road environments are improved.

[0051] The present invention will be further illustrated by the following examples. Unless otherwise specified, the materials in the examples are prepared according to existing methods or purchased directly from the market.

[0052] Example 1 This embodiment provides an embedded flexible photovoltaic module anti-glare encapsulated vehicle rearview mirror, such as... Figures 1-2As shown, a conventional optical rearview mirror for passenger cars is selected as the basic carrier. According to the design requirements of flexible perovskite photovoltaic integration, the structure of the rearview mirror body is optimized: without affecting the field of view and appearance of the mirror, a reserved mounting position for accommodating flexible solar cells is formed in the non-field area of ​​the mirror body. The mounting position is a groove-type receiving cavity that matches the outer dimensions of the flexible perovskite photovoltaic module (specifically, flexible perovskite cell). The bottom surface and side wall of the cavity (as mechanical limiting components) together form a positioning and limiting interface, so that the module can be supported and carried by the mirror body structure after being embedded, avoiding reliance on adhesive layer fixation alone. At the same time, a dedicated mounting cavity matching the energy management and energy storage components is set inside the shell, and a wiring channel and sealed wiring hole are preset to achieve reliable lead-out and protection of electrical connection.

[0053] The mounting surface and internal cavity of the mirror body in the non-field-of-view area were cleaned to ensure flatness and freedom of impurities, providing a foundation for integrated construction. A 10cm×10cm flexible perovskite solar micro-module was selected as the power generation unit. The module is formed by multiple sub-cells connected in series, and its output characteristics meet the needs of subsequent charging management. During module assembly, an adsorption layer was first laid at the bottom of the mounting slot on the housing. The adsorption layer is a polyacrylamide / polyvinyl alcohol hydrogel material, which provides initial adhesion and assembly positioning, and also uses its flexibility and damping characteristics to buffer and absorb long-term vibration and impact loads from the vehicle, reducing micro-displacement and stress concentration between the module and the housing, thereby suppressing the risk of warping and delamination. Subsequently, the flexible perovskite module was embedded in the reserved groove, so that the periphery of the module and the side wall of the groove form a limiting and bearing structure. The module is assembled with a sealing layer and a cover plate encapsulation structure formed sequentially on its upper surface. The sealing layer can be made of silicone-based / polyurethane transparent sealant to cover and bond the module surface and edges, achieving moisture-proof isolation and edge sealing of the solar cells. The anti-glare glass is made of composite cover glass with an outer surface of AG (anti-glare) and an inner surface of AR (anti-reflection) or equivalent materials, with a visible light transmittance of 90% to 98% and haze and reflectivity that meet the anti-glare requirements for suppressing strong light reflection, thereby reducing the risk of glare while ensuring effective photovoltaic incident light. A weather-resistant sealant or laminated encapsulation material is used to form a continuous sealed boundary between the cover plate and the mirror housing. After encapsulation, the cover plate is located on the outermost layer of the photovoltaic module, providing scratch and impact protection, blocking rainwater, moisture and dust intrusion, and improving long-term weather resistance.

[0054] like Figure 3 As shown ( Figure 3This is a schematic diagram of an embedded flexible photovoltaic module anti-glare encapsulation vehicle rearview mirror system. It uses an 18650 lithium-ion battery with a protection board as the energy storage unit, with a nominal voltage of 3.7V, a fully charged voltage of 4.2V, and a discharge cut-off voltage of 2.7V-3.0V. The capacity is 3-10Ah. The battery is installed in a pre-reserved cavity inside the rearview mirror via a dedicated adapter bracket. The bracket and mirror cavity are integrally fixed. The positive and negative terminals of the battery are directly connected to the MPPT circuit module via pre-laid wiring. A CN3791 MPPT solar charging module is used as the core control module, embedded in a dedicated mounting position inside the rearview mirror. The module adopts a step-down topology. The input voltage range is 4.5V-28V, compatible with the 16.46V output voltage of a series-connected photovoltaic array. It is specifically designed for the charging curve of a single 3.7V lithium-ion battery (4.2V when fully charged). The module is pre-integrated with the internal circuitry of the mirror body, requiring no additional wiring. The load circuit is integrated with the rearview mirror body. The LED lighting circuit consists of a 5mm high-brightness white LED, a 33Ω current-limiting resistor, and an SPST toggle switch. The switch is embedded in the side of the mirror body with a pre-installed button position. The circuit is integrated into the mirror body via pre-laid wiring, with the connection path as follows: battery positive terminal → SPST toggle switch → 33Ω current-limiting resistor → LED → battery negative terminal; 5V The USB charging circuit uses a DC-DC boost module with an input voltage of 3.0V-4.2V, an output voltage of 5V, and an output current of ≥1A. The module integrates a USB-A female port, which is embedded in the reserved interface position on the mirror body and flush with the surface of the mirror body. The positive and negative terminals of the module input are connected to the positive and negative terminals of the battery through pre-laid lines. The series SPST toggle switch is embedded in the side of the mirror body to realize independent control of the USB function. All circuit nodes adopt an integrated shielding design to avoid electromagnetic interference affecting the optical function of the rearview mirror.

[0055] Example 2 This embodiment provides a flexible perovskite photovoltaic module, the fabrication process of which is as follows: S1. Conductive glass ITO (100nm thick) is first ultrasonically cleaned for 15 minutes in sequence with detergent, deionized water, acetone, alcohol and isopropanol. Then it is dried with a nitrogen gun and stored for later use. Before use, the substrate is treated with a plasma cleaner at 70W power for 5 minutes to enhance the surface hydrophilicity.

[0056] S2. Preparation of hole transport layer: 4PADCB was diluted in anhydrous ethanol to a concentration of 0.5 mg / ml, and then spin-coated onto ITO conductive glass to prepare a hole transport layer. The spin-coating speed was 5000 rpm and the time was 30 s. After that, it was annealed at 100℃ for 10 min to a thickness of 2 nm.

[0057] S3. Preparation of perovskite thin film: The perovskite composition is FA. 0.95 Cs 0.05The preparation process of the PbI3 perovskite precursor solution at a concentration of 1.5 M is as follows: The perovskite precursor solution consisted of 19.5 mg CsI, 245.1 mg FAI, 691.3 mg PbI2, with an additional 10% MACl and an excess of 3% mol PbI2. The solvent was a 1 ml mixture of DMF and DMSO in a 4:1 volume ratio. The solution was stirred for 2 h until completely dissolved. For perovskite solutions containing 4-(2-pyridinylthio)benzonitrile, the concentration was 0.5 mg / ml.

[0058] The synthetic route for 4-(2-pyridinylthio)benzonitrile is as follows:

[0059] The synthesis process of 4-(2-pyridinylthio)benzonitrile is as follows: Cuprous chloride (CuCl, 14.90 mg, 0.15 mmol), ligand 6-hydroxypyridine-2-carboxamide (41.60 mg, 0.18 mmol), and potassium phosphate (K3PO4, 955.0 mg, 4.5 mmol) were added to a reaction flask, along with dimethyl sulfoxide (DMSO) as a solvent (2 M). Subsequently, 2-mercaptopyridine (366.0 mg, 3.3 mmol) and 4-bromobenzonitrile (546.0 mg, 3.0 mmol) were added, and the mixture was heated to 80 °C and reacted for approximately 20 h. After the reaction was complete, water was added to the system, and the mixture was extracted with ethyl acetate. The combined organic phases were dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure. The crude product was purified by silica gel column chromatography (eluent: n-heptane / ethyl acetate = 5 / 1) to give a colorless liquid target product (510 mg, 80%).

[0060] The process for preparing the perovskite thin film is as follows: The completely dissolved perovskite precursor solution was spin-coated onto the hole transport layer in two steps. The first step was at 1000 rpm for 10 s, and the second step was at 5000 rpm for 30 s. At the 10th second before the end of the spin-coating, 100 μL of chlorobenzene solution was added as an antisolvent. The mixture was then annealed at 100 °C for 30 min to obtain a perovskite thin film with a thickness of 800 nm.

[0061] S4. Preparation of perovskite passivation layer: Dissolve 2-phenylethylamine hydroiodide (PEAI) in isopropanol at a concentration of 0.5 mg / ml, then spin-coat it onto the perovskite layer at a spin speed of 4000 rpm for 30 s, and then anneal at 100 °C for 5 min to a thickness of 3 nm.

[0062] S5. Preparation of the electron transport layer: 20 nm C ... 60 Together with a 5nm BCP, they form an electron transport layer.

[0063] S7, Ag electrode deposited at 300nm.

[0064] Example 3 This embodiment provides a flexible perovskite photovoltaic module, which differs from Embodiment 2 in that the concentration of 4-(2-pyridinylthio)benzonitrile in the perovskite precursor is 0.3 mg / ml.

[0065] Example 4 This embodiment provides a flexible perovskite photovoltaic module, which differs from Embodiment 2 in that the concentration of 4-(2-pyridinylthio)benzonitrile in the perovskite precursor is 0.8 mg / ml.

[0066] Example 5 This embodiment provides a flexible perovskite photovoltaic module, which differs from Embodiment 2 in that the concentration of 4-(2-pyridinylthio)benzonitrile in the perovskite precursor is 0.2 mg / ml.

[0067] Example 6 This embodiment provides a flexible perovskite photovoltaic module, which differs from Embodiment 2 in that the concentration of 4-(2-pyridinylthio)benzonitrile in the perovskite precursor is 1 mg / ml.

[0068] Comparative Example 1 This comparative example provides a flexible perovskite photovoltaic module, which differs from Example 2 in that it does not contain 4-(2-pyridinylthio)benzonitrile.

[0069] Test case JV tests were performed on the devices prepared in the above embodiments and comparative examples. The test results are shown in Table 1.

[0070] Table 1

[0071] As shown in Table 1, Comparative Example 1, lacking the additive 4-(2-pyridinethio)benzonitrile, exhibited a lower photoelectric conversion efficiency than all other examples. Examples 2-4 and 5-6 demonstrate that when the concentration of the additive 4-(2-pyridinethio)benzonitrile was within a suitable range, the solar cell device modified with the additive showed improved photoelectric conversion efficiency. However, when the additive concentration was below or above this suitable range, the performance improvement effect weakened, and it even adversely affected the performance of the solar cell device.

[0072] like Figures 5-7As shown in the JV characteristic curve, the open-circuit voltage of the device in the embodiment is slightly improved, and the overall photoelectric conversion efficiency is improved, indicating that the optimized perovskite film effectively improves the device performance. From the surface SEM morphology image, the comparative film has more grain boundaries and fine grains, while the perovskite grains in the embodiment are larger, have fewer grain boundaries, and have a denser and smoother surface, indicating that the optimized process promotes grain growth and reduces grain boundary defects. In the steady-state PL spectrum of the perovskite film, the PL intensity of the embodiment is significantly higher than that of the comparative example, and the peak positions are basically the same, indicating that the defect state density of the optimized film is reduced, non-radiative recombination is effectively suppressed, and the radiative recombination efficiency of photogenerated carriers is higher.

[0073] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A flexible perovskite photovoltaic module, characterized in that, include: A hole transport layer, a perovskite thin film layer containing additives, a passivation layer, an electron transport layer, and an electrode are sequentially stacked on a conductive substrate. In this process, 4-(2-pyridinylthio)benzonitrile is introduced as an additive into the perovskite precursor to form a perovskite thin film layer.

2. The flexible perovskite photovoltaic module according to claim 1, characterized in that, The concentration of 4-(2-pyridinylthio)benzonitrile in the perovskite precursor is 0.3-0.8 mg / ml; Preferably, the thickness of the hole transport layer is 1-50 nm; Preferably, the thickness of the perovskite thin film layer containing additives is 100-1000 nm; Preferably, the thickness of the passivation layer is 1-50 nm; Preferably, the electron transport layer comprises C layers stacked sequentially. 60 Layer and BCP layer; the C 60 The thickness of the layer is 1-1000 nm; the thickness of the BCP layer is 1-1000 nm; Preferably, the electrode includes one or more of Au electrode, Ag electrode and carbon electrode; Preferably, the thickness of the electrode is 200-400 nm.

3. The method for preparing a flexible perovskite photovoltaic module as described in claim 1 or 2, characterized in that, Includes the following steps: A hole transport layer, an additive-containing perovskite thin film layer, a passivation layer, an electron transport layer, and an electrode are sequentially stacked on a conductive substrate to obtain the flexible perovskite photovoltaic module.

4. The preparation method according to claim 3, characterized in that, The hole transport layer is formed by spin coating, deposition, immersion or scraping, and then annealed at 80-120℃ for 5-10 minutes.

5. The preparation method according to claim 3, characterized in that, The perovskite thin film layer containing additives is annealed at 90-110°C for 25-35 min after being formed by spin coating, deposition, immersion or blade coating. Preferably, the perovskite precursor solution used to prepare the additive-containing perovskite thin film layer includes FA. 0.95 Cs 0.05 The concentration of the perovskite precursor solution is 1.3-1.6 M.

6. The preparation method according to claim 3, characterized in that, The passivation layer is formed by spin coating or vapor deposition and then annealed at 80-120°C for 3-8 minutes.

7. The preparation method according to claim 3, characterized in that, The electron transport layer is prepared by vapor deposition.

8. The preparation method according to claim 3, characterized in that, The electrode is prepared by vapor deposition or printing.

9. A type of embedded flexible photovoltaic module anti-glare encapsulated vehicle rearview mirror, characterized in that, include: A rearview mirror housing, wherein a mounting position is provided in the non-field-of-view area of ​​the rearview mirror housing for accommodating the flexible perovskite photovoltaic module as described in claim 1 or claim 2, or the flexible perovskite photovoltaic module prepared by the preparation method described in any one of claims 3-8.

10. The embedded flexible photovoltaic module anti-glare encapsulated vehicle rearview mirror according to claim 9, characterized in that, Also includes: An anti-glare and anti-reflective film is disposed on the side of the flexible perovskite photovoltaic module facing the external environment.

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