Interface passivation layer, perovskite solar cell, preparation method of perovskite solar cell and electrical device
The use of 3-fluoro-4-aminobenzoic acid as an interface passivation layer addresses efficiency and stability issues in perovskite solar cells by chemically interacting with defects and optimizing the cell's microstructure, resulting in enhanced performance and stability.
Patent Information
- Application Number
- CN202510460437.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-14
- Publication Date
- 2025-07-15
AI Technical Summary
Existing perovskite solar cells have problems such as low photoelectric conversion efficiency, poor stability, high production costs and great environmental impact. In particular, the organic layer of the two-dimensional perovskite layer is unstable and is easily affected by environmental factors. The passivator effect is limited and may have negative impacts on the environment.
3-fluoro-4-aminobenzoic acid is used as a multifunctional passivation material. A uniform and dense interface passivation layer is formed on the surface of perovskite solar cells through spin coating and annealing processes to fill in defects, optimize the interface morphology, reduce charge transfer resistance, and improve light absorption and charge transfer efficiency.
It significantly improves the photoelectric conversion efficiency of perovskite solar cells, enhances the structural stability and interface smoothness of the cells, reduces energy losses, is suitable for large-scale production and is environmentally friendly.
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Figure CN120322097A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of optoelectronic detection, and particularly to an interface passivation layer, a perovskite solar cell, a preparation method thereof, and an electrical device. Background Art
[0002] As a new type of photovoltaic technology, perovskite solar cells have attracted much attention due to their advantages such as high efficiency, low cost, and easy preparation. This kind of battery uses perovskite-type organometallic halide semiconductors as light-absorbing materials and belongs to the third-generation solar cell technology. Since its appearance in 2009, its photoelectric conversion efficiency has rapidly increased from 3.8% to over 25%, showing great development potential. Perovskite solar cells have a wide range of applications. They are not only suitable for large-scale photovoltaic power generation to improve power generation efficiency and reduce costs, but also, due to their thin and flexible characteristics, can be used in wearable power generation devices, photovoltaic glass building integration, and field temporary power generation equipment, etc. Although perovskite solar cells show great application prospects, they still face technical challenges such as stability and large-scale production.
[0003] In terms of improving the performance and ensuring the stability of perovskite solar cells, there are the following several mainstream technologies: 1. Surface passivation layer deposition: By depositing one or more layers of passivation layers, such as organic halides, organic semiconductor molecules, metal-organic complexes, etc., on the surface of the perovskite layer to reduce surface defects and non-radiative recombination at the interface. This technology can effectively improve the open-circuit voltage and photoelectric conversion efficiency; 2. Two-dimensional perovskite layer formation: By introducing a two-dimensional structure into the perovskite layer to form so-called two-dimensional perovskites or quantum dots to limit the generation and expansion of defects, thereby improving the stability of the battery; 3. Passivation treatment using specific molecules or compounds: Using specific small molecules, polymers, or inorganic compounds as passivation agents, these substances can react with the defects in the perovskite layer, thereby reducing non-radiative recombination. Common means: For example, using molecules such as phenylacetylene, long-chain alkylamines, phosphates, etc. as passivation agents, these molecules can bind to the defects in the perovskite layer and reduce the density of defect states; 4. Encapsulation technology: In order to improve the resistance of perovskite solar cells to environmental factors, high-performance encapsulation materials and technologies, such as double-layer encapsulation, flexible encapsulation, etc., are used to isolate humidity and oxygen and extend the service life of the battery.
[0004] However, there are still many drawbacks in the existing technologies: 1. Efficiency issues: Compared with the three-dimensional perovskite layer, the two-dimensional perovskite layer usually has lower photoelectric conversion efficiency because the two-dimensional layer reduces the light absorption ability of the material. The organic layer in the two-dimensional perovskite layer is not stable enough and is easily affected by environmental factors such as moisture, heat, and ultraviolet rays, resulting in structural degradation. The preparation process is often more complex and requires precise control of thickness and composition, which increases the production cost and difficulty. Currently, the existing passivators can only act on specific types of defects and are ineffective for other types of defects, which limits the passivation effect. 2. Stability issues: Some passivators may lose their passivation effect during long-term use, leading to a decline in battery performance. 3. Compatibility issues: Certain passivators may react with perovskite materials or other components in the battery, affecting the performance and stability of the entire battery. 4. Cost issues: Some highly efficient passivators may have high costs and are not suitable for large-scale commercial production. 5. Environmental impact: The production and use of passivators may have a negative impact on the environment.
[0005] Based on the defects existing in the above-mentioned existing technologies, how to provide a novel perovskite solar cell and its preparation method that are simple, effective, and low-cost has become an urgent problem to be solved currently. Summary of the Invention
[0006] To solve the above technical problems, the object of the present invention is to provide a perovskite solar cell, its preparation method, and its use. The perovskite solar cell of the present invention has high photoelectric conversion efficiency, reduced interface defects, reduced interface roughness, reduced charge transfer resistance at the interface, and improved light absorption efficiency and charge transport efficiency of the battery.
[0007] To achieve this purpose, the present invention adopts the following technical solutions:
[0008] In the first aspect, the present invention provides an interface passivation layer, and the material of the interface passivation layer includes 3-fluoro-4-aminobenzoic acid.
[0009] The present invention uses the multi-functional group passivation material 3-fluoro-4-aminobenzoic acid, with the chemical formula C7H6FNO2 and the structural formula: (Abbreviation: FBA) can perform fine passivation modification on the surface of perovskite solar cells. 3-Fluoro-4-aminobenzoic acid (FBA) has multiple functional groups (fluoride ion, amino group, benzene ring, carboxylic acid group), which can effectively act on the microstructure of the battery surface, thus achieving important interface modification and optimization effects: First, through the passivation effect of multiple functional groups, the energy loss at the battery interface is significantly reduced. In traditional perovskite solar cells, interface defects and instability are one of the main factors leading to energy loss. 3-Fluoro-4-aminobenzoic acid can chemically react with atoms or molecules at the interface defects, fill the defects, reduce the energy loss caused by charge recombination and interface defects, so as to ensure that more light energy is effectively converted into electrical energy.
[0010] Second, the 3-fluoro-4-aminobenzoic acid interface passivation layer further optimizes the interface morphology and improves the structural stability of the battery. The multi-functional group passivation material not only plays a role at the energy level, but also can improve the microstructure of the interface at the physical level, forming a uniform and dense passivation layer. This passivation layer can effectively reduce the interface roughness, reduce the interface trap density, and provide a smoother path for electron transport.
[0011] Third, by passivating and modifying the surface of perovskite solar cells, the light absorption efficiency and charge transport efficiency of the battery can also be improved. The presence of the interface passivation layer reduces the charge transfer resistance at the interface, making it easier for photo-generated electrons and holes to be transported from the active layer to the electrodes, thus improving the overall photoelectric conversion efficiency of the battery.
[0012] The following are the preferred technical solutions of the present invention, but do not limit the technical solutions provided by the present invention. Through the following preferred technical solutions, the technical objectives and beneficial effects of the present invention can be better achieved and realized.
[0013] In the second aspect, the present invention provides a method for preparing the interface passivation layer as described in the first aspect, and the preparation method includes the following steps: coating a 3-fluoro-4-aminobenzoic acid solution, and annealing to obtain the interface passivation layer as claimed in claim 1.
[0014] Preferably, the coating method includes spin coating at a speed of 2500 rpm - 3500 rpm. For example, it can be 2500 rpm, 2600 rpm, 2700 rpm, 2800 rpm, 2900 rpm, 3000 rpm, 3100 rpm, 3200 rpm, 3300 rpm, 3400 rpm or 3500 rpm, but is not limited to the listed values, and other unlisted values within the numerical range are equally applicable.
[0015] Preferably, the concentration of the 3-fluoro-4-aminobenzoic acid solution is 3 mg / mL - 10 mg / mL. For example, it can be 3 mg / mL, 3.5 mg / mL, 4 mg / mL, 4.5 mg / mL, 5 mg / mL, 5.5 mg / mL, 6 mg / mL, 6.5 mg / mL, 7 mg / mL, 7.5 mg / mL, 8 mg / mL, 8.5 mg / mL, 9 mg / mL, 9.5 mg / mL or 10 mg / mL. However, it is not limited to the listed values, and other unlisted values within the numerical range are equally applicable.
[0016] In the present invention, by further controlling the concentration of the 3-fluoro-4-aminobenzoic acid solution to be 3 mg / mL - 10 mg / mL, the thickness of the interfacial passivation layer is controlled. At the same time, its reaction with the defects in the perovskite absorption layer is realized, filling the defects, reducing the charge recombination and the energy loss caused by interfacial defects, reducing the interfacial roughness, and reducing the interfacial trap density, providing a smoother path for electron transport, thereby improving the photoelectric conversion efficiency of the battery. When the concentration of 3-fluoro-4-aminobenzoic acid is too low (less than 3 mg / mL), the effect of passivating defects will be insufficient. The low-concentration 3-fluoro-4-aminobenzoic acid cannot effectively passivate the surface and grain boundary defects of the perovskite film, resulting in a higher defect density, increased charge recombination, reduced carrier lifetime and battery efficiency. Moreover, too small a concentration may lead to uneven passivation effect, and the defects in some areas are not effectively passivated, affecting the consistency of battery performance and causing a large deviation in experimental results. When the passivation concentration is too high, serious ion migration may be brought about, leading to material degradation and performance attenuation, affecting the long-term stability of the battery.
[0017] Preferably, the annealing temperature is 70 °C - 110 °C. For example, it can be 70 °C, 75 °C, 80 °C, 85 °C, 90 °C, 95 °C, 100 °C, 105 °C or 110 °C. However, it is not limited to the listed values, and other unlisted values within the numerical range are equally applicable.
[0018] In the third aspect, the present invention provides a perovskite solar cell, which includes a transparent conductive layer, a hole transport layer, a perovskite absorption layer, an interfacial passivation layer as described in the first aspect, an electron transport layer and an electrode that are stacked.
[0019] In the perovskite solar cell provided by the present invention, the surface of the perovskite solar cell is passivated and modified through the interfacial passivation layer. On the one hand, 3-fluoro-4-aminobenzoic acid can chemically react with atoms or molecules at the interfacial defects, filling the defects, reducing the charge recombination and the energy loss caused by interfacial defects, thereby ensuring that more light energy is effectively converted into electrical energy.
[0020] On the other hand, 3-fluoro-4-aminobenzoic acid is used as an interfacial passivation layer to passivate and modify the surface of the perovskite solar cell, improving the structural stability of the perovskite solar cell. The multi-functional passivation material not only plays a role at the energy level but also improves the microscopic structure of the interface at the physical level, forming a uniform and dense passivation layer. This passivation layer can effectively reduce the interface roughness, decrease the interface trap density, and provide a smoother path for electron transport.
[0021] Moreover, the passivation layer can also enhance the light absorption efficiency and charge transport efficiency of the cell. The presence of the interfacial passivation layer reduces the charge transfer resistance at the interface, making it easier for photo-generated electrons and holes to be transported from the active layer to the electrodes, thereby improving the overall photoelectric conversion efficiency of the cell.
[0022] Preferably, the thickness of the interfacial passivation layer in the perovskite solar cell is 10 nm - 20 nm. For example, it can be 10 nm, 11 nm, 12 nm, 13 nm, 14 nm, 15 nm, 16 nm, 17 nm, 18 nm, 19 nm, or 20 nm, but is not limited to the listed values. Other unlisted values within the numerical range are equally applicable.
[0023] The present invention further controls the thickness of the interfacial passivation layer to be 10 nm - 20 nm. The interfacial passivation layer can perfectly achieve the functions of interfacial modification and reducing the interfacial charge transfer resistance, effectively passivating the surface and grain boundary defects of the perovskite thin film, reducing the defect density, decreasing charge recombination, enhancing the carrier lifetime and cell efficiency. In addition, this passivation helps to improve the crystallization quality of the perovskite thin film, reduce grain boundaries and pores, form a more uniform and dense thin film, and enhance the charge transport performance. If the thickness of the interfacial passivation layer is too thick, defects will be formed in the perovskite thin film, becoming charge recombination centers, resulting in increased photo-generated carrier recombination, reducing the number of effective charges, and thus decreasing the cell efficiency; if the thickness of the interfacial passivation layer is too thin, it cannot play an appropriate passivation role. When the thickness of the passivation layer is less than 5 nm, there is no obvious difference in device efficiency compared with the control group.
[0024] Preferably, the material of the transparent conductive layer includes any one or a combination of at least two of glass substrate, PET, or PEN.
[0025] Preferably, the material of the hole transport layer includes any one or a combination of at least two of PTAA, NiO x or PEDOT.
[0026] Preferably, the material of the perovskite absorption layer includes Cs 0.1 FA 0.9 Pb(I 0.6 Br 0.4 )3, FAPb(I 0.7 Br0.3 )One or any combination of at least two of CH3NH3PbI3 or FAPbI3.
[0027] Preferably, the material of the electron transport layer includes one or any combination of at least two of PCBM, BCP or C60.
[0028] Preferably, the material of the electrode layer includes one or any combination of at least two of Ag, carbon or Cu.
[0029] In the perovskite solar cell structure of the present invention, PTAA is poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine], and BCP is 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline.
[0030] The present invention does not impose special restrictions on the material of the perovskite absorption layer, and a conventional material for the perovskite absorption layer can be selected. Taking the perovskite absorption layer as Cs 0.1 FA 0.9 Pb(I 0.6 Br 0.4 )3 as an example, the preparation method of Cs 0.1 FA 0.9 Pb(I 0.6 Br 0.4 )3 includes: the perovskite absorption layer is prepared by mixing FAI (formamidinium iodide), CsI (cesium iodide), PbI2 (lead iodide), SnI2 (stannous iodide) and an additive SnF2 (stannous fluoride). The perovskite solar cell structure used in the present invention is ITO / PTAA / Cs 0.1 FA 0.9 Pb(I 0.6 Br 0.4 )3 / PCBM / BCP / Ag. The coated glass with ITO (size 25mm 2 ×25mm 2 ) is sequentially cleaned by ultrasonicating in deionized water, ethanol and isopropanol for 10 minutes each. In order to optimize the ITO surface work function and at the same time improve its wettability, the dried substrate is further treated with oxygen plasma for 10 minutes. Then, 3.5 mg mL -1The chlorobenzene solution of PTAA was spun on the ITO substrate at 4000 rpm for 30 seconds, and then immediately thermally annealed in an air environment at 120 °C for 10 minutes. After the substrate was cooled to room temperature, it was transferred to a glove box filled with nitrogen, and then the perovskite absorption layer was prepared by the blade coating method. The deposition of the perovskite precursor film was carried out on a commercial blade coater using a blade at room temperature (20 °C). (20 μL of the precursor solution was used on each substrate), the solution gap between the substrate and the blade was fixed at 200 μm, and the coating speed was fixed at 7 mm s -1 . Immediately after the blade coating was completed, the newly coated liquid precursor film was transferred to a vacuum chamber, and the vacuum was pumped to 1000 Pa within 15 seconds and maintained at this pressure for 90 s. Subsequently, the film was taken out of the vacuum chamber and annealed at 100 °C for 10 min in the glove box to crystallize the film. Having excellent light absorption coefficient, high carrier mobility and good carrier diffusion length, the materials and organic solvents used in the present invention can be obtained by purchase.
[0031] Preferably, the thickness of the transparent conductive layer is 150 nm - 300 nm, for example, it can be 150 nm, 160 nm, 170 nm, 180 nm, 190 nm, 200 nm, 210 nm, 220 nm, 230 nm, 240 nm, 250 nm, 260 nm, 270 nm, 280 nm, 290 nm or 300 nm, but is not limited to the listed values, and other unlisted values within the numerical range are equally applicable.
[0032] Preferably, the thickness of the hole transport layer is 12 nm - 25 nm, for example, it can be 12 nm, 13 nm, 14 nm, 15 nm, 16 nm, 17 nm, 18 nm, 19 nm, 20 nm, 21 nm, 22 nm, 23 nm, 24 nm or 25 nm, but is not limited to the listed values, and other unlisted values within the numerical range are equally applicable.
[0033] Preferably, the thickness of the perovskite absorption layer is 150 μm - 300 μm, for example, it can be 150 μm, 160 μm, 170 μm, 180 μm, 190 μm, 200 μm, 210 μm, 220 μm, 230 μm, 240 μm, 250 μm, 260 μm, 270 μm, 280 μm, 290 μm or 300 μm, but is not limited to the listed values, and other unlisted values within the numerical range are equally applicable.
[0034] Preferably, the thickness of the electron transport layer is 20 nm - 60 nm, for example, it can be 20 nm, 25 nm, 30 nm, 35 nm, 40 nm, 45 nm, 50 nm, 55 nm or 60 nm, but is not limited to the listed values, and other unlisted values within the numerical range are equally applicable.
[0035] Preferably, the thickness of the electrode is 50 nm - 200 nm, for example, it can be 50 nm, 60 nm, 70 nm, 80 nm, 90 nm, 100 nm, 110 nm, 120 nm, 130 nm, 140 nm, 150 nm, 160 nm, 170 nm, 180 nm, 190 nm or 200 nm, but is not limited to the listed values, and other unlisted values within the numerical range are equally applicable.
[0036] In a fourth aspect, the present invention provides a method for preparing a perovskite solar cell as described in the third aspect, and the preparation method includes the following steps:
[0037] (1) A hole transport layer is disposed on the surface of the transparent conductive layer;
[0038] (2) A perovskite absorption layer is disposed on the surface of the hole transport layer away from the transparent conductive layer;
[0039] (3) An interface passivation layer as described in the first aspect is disposed on the surface of the perovskite absorption layer away from the hole transport layer;
[0040] (4) An electron transport layer is disposed on the surface of the interface passivation layer away from the perovskite absorption layer;
[0041] (5) An electrode layer is disposed on the surface of the electron transport layer away from the interface passivation layer.
[0042] The method for preparing a perovskite solar cell provided by the present invention is simple. During the processing, the annealing temperature is lower compared with general other passivation materials, and the protection effect on the perovskite layer is better. Moreover, the material has been commercialized and the cost is lower. An interface passivation layer is directly disposed on the surface of the perovskite absorption layer away from the hole transport layer, which is different from the conventional doping process, is compatible with existing equipment, is suitable for large-scale industrial production, effectively alleviates the surface defects of the perovskite solar cell, reduces the interface roughness, and reduces the electron transport energy barrier.
[0043] Preferably, the method for disposing the hole transport layer includes first coating a hole transport layer material solution on the transparent conductive layer and performing a first annealing treatment to obtain the hole transport layer.
[0044] Preferably, the method for disposing the perovskite absorption layer includes second coating a perovskite precursor solution on the hole transport layer and performing a second annealing treatment to obtain the perovskite absorption layer.
[0045] Preferably, the method for setting the electron transport layer includes spin-coating an electron transport layer material on the interface passivation layer to prepare the electron transport layer.
[0046] Preferably, the method for setting the electrode layer includes depositing the electrode layer on the electron transport layer.
[0047] Preferably, before use, the transparent conductive layer also includes cleaning the transparent conductive layer and pre-treating it with oxygen plasma.
[0048] Preferably, the cleaning step includes ultrasonic treatment in water, ethanol, and isopropanol for 10 min - 30 min, for example, it can be 10 min, 15 min, 20 min, 25 min, or 30 min, but is not limited to the listed values, and other unlisted values within the numerical range are equally applicable.
[0049] Preferably, the solution concentration of the hole transport layer material is 1 mg / mL - 10 mg / mL, for example, it can be 1 mg / mL, 1.5 mg / mL, 2 mg / mL, 2.5 mg / mL, 3 mg / mL, 3.5 mg / mL, 4 mg / mL, 4.5 mg / mL, 5 mg / mL, 5.5 mg / mL, 6 mg / mL, 6.5 mg / mL, 7 mg / mL, 7.5 mg / mL, 8 mg / mL, 8.5 mg / mL, 9 mg / mL, 9.5 mg / mL, or 10 mg / mL, but is not limited to the listed values, and other unlisted values within the numerical range are equally applicable.
[0050] Preferably, the rotation speed of the first spin-coating is 4000 rpm - 5000 rpm, for example, it can be 4000 rpm, 4100 rpm, 4200 rpm, 4300 rpm, 4400 rpm, 4500 rpm, 4600 rpm, 4700 rpm, 4800 rpm, 4900 rpm, or 5000 rpm, but is not limited to the listed values, and other unlisted values within the numerical range are equally applicable.
[0051] Preferably, the time of the first spin-coating is 10 s - 60 s, for example, it can be 10 s, 20 s, 30 s, 40 s, 50 s, or 60 s, but is not limited to the listed values, and other unlisted values within the numerical range are equally applicable.
[0052] Preferably, the temperature of the first annealing is 110 °C - 150 °C, for example, it can be 110 °C, 115 °C, 120 °C, 125 °C, 130 °C, 135 °C, 140 °C, 145 °C, or 150 °C, but is not limited to the listed values, and other unlisted values within the numerical range are equally applicable.
[0053] Preferably, the time of the first annealing is 5 min - 20 min. For example, it can be 5 min, 10 min, 15 min, or 20 min, but is not limited to the listed values. Other unlisted values within the numerical range are equally applicable.
[0054] Preferably, the concentration of the perovskite precursor solution for coating is 3 mg / mL - 10 mg / mL. For example, it can be 3 mg / mL, 3.5 mg / mL, 4 mg / mL, 4.5 mg / mL, 5 mg / mL, 5.5 mg / mL, 6 mg / mL, 6.5 mg / mL, 7 mg / mL, 7.5 mg / mL, 8 mg / mL, 8.5 mg / mL, 9 mg / mL, 9.5 mg / mL, or 10 mg / mL, but is not limited to the listed values. Other unlisted values within the numerical range are equally applicable.
[0055] Preferably, the method of the second coating is blade coating.
[0056] Preferably, the speed of the blade coating is 5 mm / s - 10 mm / s. For example, it can be 5 mm / s, 6 mm / s, 7 mm / s, 8 mm / s, 9 mm / s, or 10 mm / s, but is not limited to the listed values. Other unlisted values within the numerical range are equally applicable.
[0057] Preferably, the temperature of the second annealing is 100 °C - 130 °C. For example, it can be 100 °C, 105 °C, 110 °C, 115 °C, 120 °C, 125 °C, or 130 °C, but is not limited to the listed values. Other unlisted values within the numerical range are equally applicable.
[0058] Preferably, the time of the second annealing is 5 min - 20 min. For example, it can be 5 min, 10 min, 15 min, or 20 min, but is not limited to the listed values. Other unlisted values within the numerical range are equally applicable.
[0059] Preferably, the atmosphere of the second annealing is an inert atmosphere.
[0060] Preferably, the inert atmosphere includes helium and / or argon.
[0061] Preferably, the solvent in the 3-fluoro-4-aminobenzoic acid solution includes isopropanol.
[0062] Preferably, the method of the third coating is spin coating.
[0063] Preferably, the rotation speed of spin coating is 2500 rpm - 3500 rpm. For example, it can be 2500 rpm, 2600 rpm, 2700 rpm, 2800 rpm, 2900 rpm, 3000 rpm, 3100 rpm, 3200 rpm, 3300 rpm, 3400 rpm or 3500 rpm. However, it is not limited to the listed values, and other unlisted values within the numerical range are equally applicable.
[0064] In the present invention, by further controlling the concentration of 3-fluoro-4-aminobenzoic acid solution to be 3 mg / mL - 10 mg / mL, the thickness of the interfacial passivation layer is controlled, and at the same time, its reaction with the defects in the perovskite absorption layer is realized, filling the defects, reducing the charge recombination and the energy loss caused by interfacial defects, reducing the interfacial roughness, reducing the interfacial trap density, providing a smoother path for electron transport, thereby improving the photoelectric conversion efficiency of the battery. When the concentration of 3-fluoro-4-aminobenzoic acid is too low (less than 3 mg / mL), the effect of passivating defects will be insufficient. The low-concentration 3-fluoro-4-aminobenzoic acid cannot effectively passivate the surface and grain boundary defects of the perovskite film, resulting in a higher defect density, increased charge recombination, reduced carrier lifetime and battery efficiency. And too small a concentration may lead to uneven passivation effect, and the defects in some areas are not effectively passivated, affecting the consistency of battery performance and causing a large deviation in experimental results; while when the passivation concentration is too high, serious ion migration may be brought about, causing material degradation and performance attenuation, affecting the long-term stability of the battery.
[0065] Preferably, the concentration of the PCBM solution is 10 mg / mL - 50 mg / mL. For example, it can be 10 mg / mL, 15 mg / mL, 20 mg / mL, 25 mg / mL, 30 mg / mL, 35 mg / mL, 40 mg / mL, 45 mg / mL or 50 mg / mL. However, it is not limited to the listed values, and other unlisted values within the numerical range are equally applicable.
[0066] Preferably, the concentration of the BCP solution is 1 mg / mL - 10 mg / mL. For example, it can be 1 mg / mL, 1.5 mg / mL, 2 mg / mL, 2.5 mg / mL, 3 mg / mL, 3.5 mg / mL, 4 mg / mL, 4.5 mg / mL, 5 mg / mL, 5.5 mg / mL, 6 mg / mL, 6.5 mg / mL, 7 mg / mL, 7.5 mg / mL, 8 mg / mL, 8.5 mg / mL, 9 mg / mL, 9.5 mg / mL or 10 mg / mL. However, it is not limited to the listed values, and other unlisted values within the numerical range are equally applicable.
[0067] As a preferred technical solution of the preparation method of the present invention, the preparation method includes the following steps:
[0068] (1) The transparent conductive layer is ultrasonically treated in water, ethanol, and isopropanol for 10 min - 30 min in sequence, and then the transparent conductive layer is pretreated with oxygen plasma;
[0069] (2) A hole transport layer solution with a concentration of 1 mg / mL - 10 mg / mL is spin-coated on the pretreated transparent conductive layer, and is first annealed at 110°C - 150°C for 5 min - 20 min in an air atmosphere to obtain a hole transport layer;
[0070] (3) A perovskite precursor solution with a concentration of 3 mg / mL - 10 mg / mL is blade-coated on the hole transport layer at a speed of 5 mm / s - 10 mm / s, and is second annealed at 100°C - 130°C for 5 min - 20 min in an inert atmosphere to obtain a perovskite absorption layer;
[0071] (4) A 3-fluoro-4-aminobenzoic acid solution with a concentration of 3 mg / mL - 10 mg / mL is spin-coated on the perovskite absorption layer at a rotation speed of 2500 rpm - 3500 rpm, and is annealed at 70°C - 110°C to obtain an interface passivation layer;
[0072] (5) A PCBM solution (chlorobenzene solution) with a concentration of 10 mg / mL - 50 mg / mL and a BCP solution (isopropanol solution) with a concentration of 1 mg / mL - 10 mg / mL are third-coated on the interface passivation layer at rotation speeds of 2000 rpm and 5000 rpm respectively to prepare an electron transport layer;
[0073] (6) An Ag electrode layer with a thickness of 50 nm - 200 nm is deposited on the electron transport layer at a rate of , and finally a perovskite solar cell is obtained, with an effective area of 0.05 cm 2 - 0.1 cm 2 .
[0074] In a fifth aspect, the present invention provides an electrical device, and the electrical device includes the perovskite solar cell described in the third aspect or the perovskite solar cell prepared by the preparation method described in the fourth aspect.
[0075] The perovskite solar cell of the present invention has excellent photoelectric conversion efficiency and has broad application prospects.
[0076] The numerical ranges described in the present invention not only include the above-listed point values, but also include any point values between the above numerical ranges not listed. Due to space limitations and for the sake of brevity, the present invention does not exhaustively list the specific point values included in the ranges.
[0077] Compared with the prior art, the present invention has at least the following beneficial effects:
[0078] (1) The interfacial passivation layer provided by the present invention is 3-fluoro-4-aminobenzoic acid (abbreviation: FBA). As a multi-functional group (fluoride ion, amino group, benzene ring, carboxylic acid group) passivation material, it can perform fine passivation modification on the surface of perovskite solar cells. Through the passivation effect of multi-functional groups, the energy loss at the battery interface is significantly reduced. 3-fluoro-4-aminobenzoic acid can carry out chemical reactions with atoms or molecules at the interface defects, fill the defects, reduce the energy loss caused by charge recombination and interface defects, thereby ensuring that more light energy is effectively converted into electrical energy.
[0079] (2) The present invention uses 3-fluoro-4-aminobenzoic acid as the interfacial passivation layer to passivate and modify the surface of perovskite solar cells, improving the structural stability of perovskite solar cells. The multi-functional group passivation material not only plays a role at the energy level but also can improve the microscopic structure of the interface at the physical level, forming a uniform and dense passivation layer. This passivation layer can effectively reduce the interface roughness, reduce the interface trap density, and provide a smoother path for electron transport.
[0080] (3) The present invention uses 3-fluoro-4-aminobenzoic acid as the interfacial passivation layer to passivate and modify the surface of perovskite solar cells, and can also improve the light absorption efficiency and charge transport efficiency of the battery. The presence of the interfacial passivation layer reduces the charge transfer resistance at the interface, making it easier for photo-generated electrons and holes to be transported from the active layer to the electrode, thereby improving the overall photoelectric conversion efficiency of the battery. Description of the Drawings
[0081] Figure 1 is a schematic structural diagram of the perovskite solar cell in Example 1 of the present invention; wherein, 1 - transparent conductive layer, 2 - hole transport layer, 3 - perovskite absorption layer, 4 - interfacial passivation layer, 5 - electron transport layer, 6 - electrode layer;
[0082] Figure 2 is the UPS test curve of the perovskite solar cell in Example 1 of the present invention;
[0083] Figure 3 is the UPS test curve of the perovskite solar cell in Comparative Example 1 of the present invention;
[0084] Figure 4 is a schematic diagram of the HOMO energy level change of the perovskite solar cells in Example 1 and Comparative Example 1 of the present invention;
[0085] Figure 5 is the J-V curve of the perovskite solar cells in Example 1 and Comparative Example 1 of the present invention;
[0086] Figure 6 is the SEM image of the interface of the perovskite solar cells in Example 1 and Comparative Example 1 of the present invention;
[0087] Figure 7 It is the atomic force microscope image of the perovskite solar cell in Example 1 and Comparative Example 1 of the present invention. Specific embodiments
[0088] The technical solution of the present invention will be further described below in conjunction with the accompanying drawings and through specific embodiments. However, the following examples are only simple examples of the present invention and do not represent or limit the scope of the claimed protection of the present invention. The scope of protection of the present invention shall be subject to the claims.
[0089] In the following examples and comparative examples, unless otherwise specified, all reagents and consumables are purchased from conventional reagent manufacturers in the art; unless otherwise specified, the experimental methods and technical means used are conventional methods and means in the art.
[0090] Example 1
[0091] This example provides a perovskite solar cell. The structural schematic diagram of the perovskite solar cell is as Figure 1 shown, including a transparent conductive layer (ITO), a hole transport layer (PTAA), a perovskite absorption layer (Cs 0.1 FA 0.9 Pb(I 0.6 Br 0.4 )3), an interface passivation layer (FBA), an electron transport layer (PCBM), and an electrode (Ag) arranged in layers; the interface passivation layer includes 3-fluoro-4-aminobenzoic acid, and the thickness of the interface passivation layer is 15 nm;
[0092] The preparation method of the perovskite solar cell provided in this example includes the following steps:
[0093] (1) Ultrasonically treat the transparent conductive layer in water, ethanol, and isopropanol for 10 min in sequence, and then pretreat the transparent conductive layer with oxygen plasma;
[0094] (2) Spin-coat a PTAA solution with a concentration of 3.5 mg / mL on the pretreated transparent conductive layer, and perform a first annealing treatment at 120 °C for 10 min in an air atmosphere to obtain a hole transport layer;
[0095] (3) Knife-coat a perovskite precursor solution with a concentration of 1 M on the hole transport layer at a speed of 7 mm / s, transfer it to a vacuum chamber, evacuate the vacuum to 1000 Pa within 15 s, and maintain this pressure for 90 s. Perform a second annealing treatment at 100 °C for 10 min in an argon atmosphere to obtain a perovskite absorption layer;
[0096] (4) A 3-fluoro-4-aminobenzoic acid solution with a concentration of 5 mg / mL was spin-coated on the perovskite absorption layer at a speed of 3000 rpm, and annealed at 80 °C to obtain an interfacial passivation layer;
[0097] (5) A PCBM solution and a BCP solution with concentrations of 25 mg / mL and 2.5 mg / mL were sequentially spin-coated on the interfacial passivation layer at speeds of 2000 rpm and 5000 rpm respectively to prepare an electron transport layer;
[0098] (6) An Ag electrode with a thickness of 120 nm was deposited on the electron transport layer, and finally a perovskite solar cell was obtained.
[0099] The UPS test curve of the prepared perovskite solar cell is as Figure 2 shown, and the schematic diagram of the HOMO energy level change is as Figure 4 shown. It can be seen from Figure 2 and Figure 4 that after passivation with FBA, the HOMO energy level of the perovskite absorption layer becomes shallower, which is beneficial to reducing the energy barrier of electron transfer.
[0100] The J-V curve of the prepared perovskite solar cell is as Figure 5 shown. It can be seen from Figure 5 that the introduction of the FBA passivator reduces the non-radiative recombination on the surface of the perovskite thin film, the open-circuit voltage is improved, and at the same time, the carrier transport at the interface is enhanced and the current is enhanced.
[0101] The SEM image of the interface of the prepared perovskite solar cell is as Figure 6 shown, and the atomic force microscope image is as Figure 7 shown. It can be seen from Figure 6 and Figure 7 that the addition of FBA modifies the surface morphology of the perovskite absorption layer, with smaller roughness and more uniform grain size.
[0102] Example 2
[0103] This example provides a perovskite solar cell, which includes a transparent conductive layer, a hole transport layer, a perovskite absorption layer (Cs 0.1 FA 0.9 Pb(I 0.6 Br 0.4 )3), an interfacial passivation layer, an electron transport layer and an electrode; the interfacial passivation layer includes 3-fluoro-4-aminobenzoic acid, and the thickness of the interfacial passivation layer is 10 nm;
[0104] The preparation method of the perovskite solar cell provided in this example includes the following steps:
[0105] (1) The transparent conductive layer was ultrasonically treated in water, ethanol, and isopropanol for 20 min in sequence, and then the transparent conductive layer was pretreated with oxygen plasma;
[0106] (2) A PTAA solution with a concentration of 5 mg / mL was spin-coated on the pretreated transparent conductive layer, and was first annealed at 130 °C for 10 min in an air atmosphere to obtain a hole transport layer;
[0107] (3) A perovskite precursor solution with a concentration of 3 M was blade-coated on the hole transport layer at a speed of 5 mm / s, transferred to a vacuum chamber, the vacuum was pumped to 1000 Pa within 15 s, and maintained at this pressure for 90 s. In an argon atmosphere, it was second annealed at 120 °C for 5 min to obtain a perovskite absorption layer;
[0108] (4) A 3-fluoro-4-aminobenzoic acid solution with a concentration of 3.5 mg / mL was spin-coated on the perovskite absorption layer at a rotation speed of 2500 rpm, and annealed at 90 °C to obtain an interfacial passivation layer;
[0109] (5) A PCBM solution with a concentration of 15 mg / mL and a BCP solution with a concentration of 2 mg / mL were third-coated on the interfacial passivation layer at rotation speeds of 2000 rpm and 5000 rpm in sequence to prepare an electron transport layer;
[0110] (6) An Ag electrode with a thickness of 100 nm was deposited on the electron transport layer, and finally a perovskite solar cell was obtained.
[0111] Example 3
[0112] This example provides a perovskite solar cell, which includes a transparent conductive layer, a hole transport layer, a perovskite absorption layer (Cs 0.1 FA 0.9 Pb(I 0.6 Br 0.4 )3), an interfacial passivation layer, an electron transport layer, and an electrode that are stacked; the interfacial passivation layer includes 3-fluoro-4-aminobenzoic acid, and the thickness of the interfacial passivation layer is 20 nm;
[0113] The preparation method of the perovskite solar cell provided in this example includes the following steps:
[0114] (1) The transparent conductive layer was ultrasonically treated in water, ethanol, and isopropanol for 30 min in sequence, and then the transparent conductive layer was pretreated with oxygen plasma;
[0115] (2) A PTAA solution with a concentration of 10 mg / mL was spin-coated on the pretreated transparent conductive layer, and was first annealed at 130 °C for 10 min in an air atmosphere to obtain a hole transport layer;
[0116] (3) The perovskite precursor solution with a concentration of 5 M was spin-coated on the hole transport layer at a speed of 10 mm / s, transferred to a vacuum chamber, the vacuum was pumped to 1000 Pa within 15 seconds, and maintained at this pressure for 90 s. In an argon atmosphere, it was annealed at 130 °C for 5 min to obtain the perovskite absorption layer;
[0117] (4) A solution of 3-fluoro-4-aminobenzoic acid with a concentration of 8 mg / mL was spin-coated on the perovskite absorption layer at a speed of 3500 rpm, and annealed at 100 °C to obtain the interfacial passivation layer;
[0118] (5) The electron transport layer was prepared by successively spin-coating PCBM solution with a concentration of 50 mg / mL and BCP solution with a concentration of 10 mg / mL on the interfacial passivation layer at speeds of 2000 rpm and 5000 rpm respectively;
[0119] (6) An Ag electrode with a thickness of 150 nm was deposited on the electron transport layer, and finally a perovskite solar cell was obtained.
[0120] Example 4
[0121] This example provides a perovskite solar cell. The difference from Example 1 is only that in the perovskite solar cell, the thickness of the interfacial passivation layer is 100 nm.
[0122] Example 5
[0123] This example provides a perovskite solar cell. The difference from Example 1 is only that in the perovskite solar cell, the thickness of the interfacial passivation layer is 5 nm.
[0124] Example 6
[0125] This example provides a perovskite solar cell. The difference from Example 1 is only that when preparing the perovskite solar cell based on the interfacial passivation layer, the concentration of the 3-fluoro-4-aminobenzoic acid solution used in step (4) is 50 mg / mL.
[0126] Example 7
[0127] This example provides a perovskite solar cell. The difference from Example 1 is only that when preparing the perovskite solar cell based on the interfacial passivation layer, the concentration of the 3-fluoro-4-aminobenzoic acid solution used in step (4) is 1 mg / mL.
[0128] Comparative Example 1
[0129] This comparative example provides a perovskite solar cell. The difference from Example 1 is only that when preparing the perovskite solar cell, step (4) was not carried out, that is, there is no interfacial modification layer in the solar cell.
[0130] The UPS test curve of the prepared perovskite solar cell is as Figure 3 shown, and the schematic diagram of the HOMO energy level change is as Figure 4 shown. It can be seen from Figure 3 and Figure 4 that the perovskite without FBA passivation has a lower HOMO energy level, a deeper energy level barrier, which increases the energy required for carrier transfer and is not conducive to electron transfer.
[0131] The J-V curve of the prepared perovskite solar cell is as Figure 5 shown. It can be seen from Figure 5 that both the open-circuit voltage and short-circuit current density of the passivated device are improved to a certain extent, thus realizing the enhancement of the photoelectric conversion efficiency.
[0132] The SEM image of the interface of the prepared perovskite solar cell is as Figure 6 shown, and the atomic force microscope image is as Figure 7 shown. It can be seen from Figure 6 and Figure 7 that if FBA is not used to modify the interface of the perovskite solar cell, its surface morphology is rough and the grain size is uneven.
[0133] Comparative Example 2
[0134] This comparative example provides a perovskite solar cell, which is only different from Example 1 in that when preparing this perovskite solar cell, the 3-fluoro-4-aminobenzoic acid solution in step (4) is replaced with 4-amino-2,3,5,6-tetrafluorobenzoic acid with the same concentration.
[0135] Test method: The perovskite solar cells prepared in Examples 1-7 and Comparative Examples 1-2 were tested, and the test results are shown in Table 1 below.
[0136] Table 1
[0137]
[0138]
[0139] It can be seen from the test results that:
[0140] (1) As can be seen from Examples 1 - 3, by using 3 - fluoro - 4 - aminobenzoic acid with multiple functional groups as the interfacial passivation layer, the present invention realizes the function of finely passivating the surface of perovskite solar cells. The 3 - fluoro - 4 - aminobenzoic acid interfacial passivation layer, on the one hand, can effectively act on the microstructure of the perovskite solar cell surface, carry out chemical reactions with atoms or molecules at the interfacial defects, fill the defects, and reduce the charge recombination and energy loss caused by interfacial defects. On the other hand, it optimizes the interfacial morphology, reduces the interfacial roughness, provides a smoother path for electron transport, and at the same time reduces the charge transfer resistance at the interface, improving the overall photoelectric conversion efficiency of the battery and achieving a photoelectric conversion efficiency of more than 17.8%.
[0141] (2) As can be seen from the comparison between Example 1 and Examples 4 - 5, by further controlling the thickness of the interfacial passivation layer to be 10 nm - 20 nm, the interfacial passivation layer of the present invention can perfectly achieve the function of interfacial modification and reduce the interfacial charge transfer resistance, effectively passivate the surface and grain boundary defects of the perovskite film, reduce the defect density, reduce charge recombination, improve the carrier lifetime and battery efficiency. In addition, this passivation helps to improve the crystallization quality of the perovskite film, reduce grain boundaries and pores, form a more uniform and dense film, and enhance the charge transport performance. If the thickness of the interfacial passivation layer is too thick, it may change the energy level structure of the perovskite material, resulting in an energy level mismatch with the electron or hole transport layer, increasing the interfacial resistance and hindering charge extraction and transport; if the thickness of the interfacial passivation layer is too thin and the concentration is insufficient, 3 - fluoro - 4 - aminobenzoic acid is difficult to improve the crystallization quality of the perovskite film, which may lead to an uneven film with more grain boundaries and pores, affecting the charge transport performance.
[0142] (3) As can be seen from the comparison between Example 1 and Examples 6 - 7, by further controlling the concentration of the 3 - fluoro - 4 - aminobenzoic acid solution to be 3 mg / mL - 10 mg / mL to control the thickness of the interfacial passivation layer, and at the same time realizing its reaction with the defects in the perovskite absorption layer, filling the defects, reducing the charge recombination and energy loss caused by interfacial defects, reducing the interfacial roughness, and reducing the interfacial trap density, providing a smoother path for electron transport, thereby improving the photoelectric conversion efficiency of the battery. When the concentration of 3 - fluoro - 4 - aminobenzoic acid is too low (less than 3 mg / mL), the effect of passivating defects will be insufficient. The low - concentration 3 - fluoro - 4 - aminobenzoic acid cannot effectively passivate the surface and grain boundary defects of the perovskite film, resulting in a higher defect density, increased charge recombination, reduced carrier lifetime and battery efficiency, and too small a concentration may lead to uneven passivation effects, with some regions of defects not being effectively passivated, affecting the consistency of battery performance and causing a large deviation in experimental results; while when the passivation concentration is too high, it may cause serious ion migration, leading to material degradation and performance attenuation, affecting the long - term stability of the battery.
[0143] (4) Through Example 1 and Comparative Example 1 and Figures 4 - 7 It can be seen that when the interfacial passivation layer is not introduced, the electron transfer energy barrier is very high, and the interface of the perovskite absorption layer is rough and unstable. The photoelectric conversion efficiency of the solar cell is only 13.3%.
[0144] (5) Through Example 1 and Comparative Example 2, it can be seen that by selecting the 3-fluoro-4-aminobenzoic acid material containing multiple functional groups (fluoride ion, amino group, benzene ring, carboxylic acid group), the present invention can significantly improve the interfacial stability and photoelectric conversion efficiency of the perovskite solar cell. However, when 4-amino-2,3,5,6-tetrafluorobenzoic acid is used, the introduction of too many F ions will cause too many defects, resulting in serious interfacial phase segregation and reducing the photoelectric conversion efficiency and stability of the perovskite solar cell.
[0145] In summary, by using 3-fluoro-4-aminobenzoic acid with multiple functional groups as the interfacial passivation layer, the present invention realizes the function of fine passivation of the surface of the perovskite solar cell. The 3-fluoro-4-aminobenzoic acid interfacial passivation layer, on the one hand, can effectively act on the microstructure of the surface of the perovskite solar cell, carry out chemical reactions with atoms or molecules at the interfacial defects, fill the defects, and reduce the energy loss caused by charge recombination and interfacial defects. On the other hand, it optimizes the interfacial morphology, reduces the interfacial roughness, provides a smoother path for electron transport, and at the same time reduces the charge transfer resistance at the interface, improving the overall photoelectric conversion efficiency of the battery.
[0146] The applicant declares that the above is only the specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention fall within the protection scope and the disclosure scope of the present invention.
Claims
1. An interface passivation layer, characterized in that, The material of the interface passivation layer includes 3-fluoro-4-aminobenzoic acid.
2. A method for preparing an interface passivation layer, characterized in that, The preparation method includes the following steps: coating a 3-fluoro-4-aminobenzoic acid solution and annealing to obtain the interface passivation layer described in claim 1.
3. The preparation method according to claim 2, characterized in that, The coating method includes spin coating at a rotation speed of 2500 rpm - 3500 rpm; and / or, the concentration of the 3-fluoro-4-aminobenzoic acid solution is 3 mg / mL - 10 mg / mL; and / or, the annealing temperature is 70°C - 110°C.
4. A perovskite solar cell, characterized in that, The perovskite solar cell includes a transparent conductive layer, a hole transport layer, a perovskite absorption layer, the interface passivation layer described in claim 1, an electron transport layer, and an electrode layer that are stacked.
5. The perovskite solar cell according to claim 4, characterized in that, The thickness of the interface passivation layer in the perovskite solar cell is 10 - 20 nm.
6. The perovskite solar cell according to claim 4 or 5, characterized in that, The material of the transparent conductive layer includes any one or a combination of at least two of a glass substrate, PET, or PEN; And / or, the material of the hole transport layer includes any one or a combination of at least two of PTAA, NiO x or PEDOT; and / or, the material of the perovskite absorption layer includes Cs 0.1 FA 0.9 Pb(I 0.6 Br 0.4 )3, FAPb(I 0.7 Br 0.3 )3 or any combination of at least two of FAPbI3; and / or, the material of the electron transport layer includes any one or a combination of at least two of PCBM, BCP, or C60; and / or, the material of the electrode layer includes any one or a combination of at least two of Ag, carbon, or Cu.
7. The perovskite solar cell according to any one of claims 4-6, characterized in that, The thickness of the transparent conductive layer is 150 nm - 300 nm; and / or, the thickness of the hole transport layer is 12 nm - 25 nm; and / or, the thickness of the perovskite absorption layer is 150 μm - 300 μm; and / or, the thickness of the electron transport layer is 20 nm - 60 nm; and / or, the thickness of the electrode layer is 50 nm - 200 nm.
8. A method for preparing a perovskite solar cell according to any one of claims 4-7, characterized in that, The preparation method includes the following steps: (1) A hole transport layer is provided on the surface of the transparent conductive layer; (2) A perovskite absorption layer is provided on the surface of the hole transport layer away from the transparent conductive layer; (3) The interface passivation layer described in claim 1 is provided on the surface of the perovskite absorption layer away from the hole transport layer; (4) An electron transport layer is provided on the surface of the interface passivation layer away from the perovskite absorption layer; (5) An electrode layer is provided on the surface of the electron transport layer away from the interface passivation layer.
9. The preparation method according to claim 8, wherein The method for providing the hole transport layer includes first coating a hole transport layer material solution on the transparent conductive layer and performing a first annealing treatment to obtain the hole transport layer; and / or, the method for providing the perovskite absorption layer includes second coating a perovskite precursor solution on the hole transport layer and performing a second annealing treatment to obtain the perovskite absorption layer; and / or, the method for providing the electron transport layer includes third coating an electron transport layer material on the interface passivation layer to prepare the electron transport layer; and / or, the method for providing the electrode layer includes depositing the electrode layer on the electron transport layer.
10. An electrical device, characterized in that, The electrical device includes the perovskite solar cell according to any one of claims 4 - 7.
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Passivation molecule and perovskite solar cell
CN121226286A