Pyridine-3, 5-dicarboxylic acid modified / doped all-inorganic perovskite solar cell and preparation method thereof
By modifying/doping the TiO2 electron transport layer with pyridine-3,5-dicarboxylic acid, the interface defect and energy level matching problems of all-inorganic perovskite solar cells were solved, and the carrier mobility and battery efficiency were improved.
Patent Information
- Application Number
- CN202510850638.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-24
- Publication Date
- 2025-09-23
AI Technical Summary
Existing all-inorganic perovskite solar cells have problems such as high interface defect state density on the TiO2 surface, perovskite lattice distortion, and poor matching between the TiO2 Fermi level and the perovskite conduction band gradient, which leads to decreased carrier mobility and limited cell efficiency.
The TiO2 electron transport layer is modified or doped with pyridine-3,5-dicarboxylic acid, and the interface defects are passivated through the molecular coordination mechanism to form a stable Ti-OCO-Ti bridging structure. A gradient energy level structure is constructed through energy level regulation to optimize the electron collection and carrier extraction efficiency.
Effectively reduce the oxygen vacancy defect state density, improve electron mobility, reduce open circuit voltage loss, and increase the photoelectric conversion efficiency to 11.86%-14.05%.
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Figure CN120693043A_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the technical field of perovskite solar cells, and in particular relates to a pyridine-3,5-dicarboxylic acid modified / doped all-inorganic perovskite solar cell and a preparation method thereof. Background Art
[0002] All-inorganic perovskite solar cells have become a research focus in the photovoltaic field due to their high thermal stability (>200℃) and wide spectral absorption characteristics (band gap 1.71-2.3 eV). Although traditional devices using mesoporous titanium dioxide (TiO2) as an electron transport layer (ETL) can achieve a certified efficiency of 21.8%, their reliance on high-temperature annealing (>450℃) makes it difficult to control the crystallinity and is not compatible with flexible substrates, hindering their commercial application. Planar heterojunction structures have attracted much attention due to their low-temperature processing (<150℃) and simplified device architecture, but their core challenge is that the low-temperature prepared TiO2 ETL has intrinsic defects. The TiO2 (101) crystal plane is mismatched with the CsPbI3 (100) crystal plane, resulting in perovskite lattice distortion and reduced carrier mobility. In addition, in a humid and hot environment (85℃ / 85%RH), hydroxylation on the TiO2 surface accelerates the hydrolysis and decomposition of the perovskite, and the life of unencapsulated devices is less than 100 hours.
[0003] Current interface optimization strategies face multiple bottlenecks. While traditional organic passivators can reduce the density of interface defect states through monodentate coordination, they suffer from poor thermal stability (deletion after 48 hours at 85°C) and susceptibility to UV light dissociation, making them incapable of inhibiting the photocatalytic decomposition of perovskites induced by TiO2. Furthermore, solvent compatibility is a significant issue: TiO2 precursor solutions (such as isopropyl titanate) readily undergo redissolution reactions with the perovskite active layer, resulting in pinhole defects in the film and reducing the device fill factor (FF) to below 75%. Regarding bandgap engineering, existing technologies struggle to simultaneously adjust the gradient between the TiO2 Fermi level (-4.2 eV) and the perovskite conduction band (-3.8 eV). The interface barrier (0.8 eV) leads to electron accumulation, resulting in an open-circuit voltage (Voc) loss exceeding 0.3 V. Although alternative materials such as SnO2 exhibit low hysteresis, their weak interfacial adhesion to perovskites and the tendency to form deep-level defects at grain boundaries hinder further efficiency improvements.
[0004] Considering the above problems, we need to develop a new method to optimize the interface between titanium dioxide and perovskite to achieve efficient electron collection, reduce battery defects and improve the energy conversion efficiency of the battery. Summary of the Invention
[0005] In order to overcome the shortcomings of the above-mentioned prior art, the purpose of the present invention is to provide a pyridine-3,5-dicarboxylic acid modified / doped all-inorganic perovskite solar cell and a preparation method thereof, so as to solve the technical problems of high interface defect state density on the TiO2 surface, accelerated hydrolysis and decomposition of perovskite by surface hydroxylation, perovskite lattice distortion and gradient matching of TiO2 Fermi level and perovskite conduction band.
[0006] In order to achieve the above object, the present invention adopts the following technical solutions: The present invention also provides a method for preparing a pyridine-3,5-dicarboxylic acid modified / doped all-inorganic perovskite solar cell, comprising the following steps: A planar TiO2 electron transport layer is prepared on a substrate; pyridine-3,5-dicarboxylic acid powder is dissolved in DMF to prepare a pyridine-3,5-dicarboxylic acid solution; the pyridine-3,5-dicarboxylic acid solution is dropwise added onto the planar TiO2 electron transport layer and spin-coated, followed by heat treatment to achieve crystallization, thereby obtaining a pyridine-3,5-dicarboxylic acid modified layer; Alternatively, pyridine-3,5-dicarboxylic acid powder is added to a TiCl4 icy water solution to prepare a complex aqueous solution, and the complex aqueous solution is used to prepare a pyridine-3,5-dicarboxylic acid-doped TiO2 electron transport layer on a substrate; CsPbI was sequentially prepared on top of the pyridine-3,5-dicarboxylic acid modified layer or the pyridine-3,5-dicarboxylic acid doped TiO2 electron transport layer. 3-x Br x A perovskite light absorption layer, a Spiro-OMeTAD hole transport layer, and then a layer of Ag electrode evaporated on the top to produce a pyridine-3,5-dicarboxylic acid modified / doped all-inorganic perovskite solar cell.
[0007] In one embodiment, the concentration of the pyridine-3,5-dicarboxylic acid solution is 25 mg / mL to 100 mg / mL.
[0008] In one embodiment, the spin coating is a two-stage step-by-step spin coating, wherein the first stage is a low-speed spin coating at 500-1500 rpm for 5-10 s, and the second stage is a high-speed spin coating at 3000-5000 rpm for 20-30 s.
[0009] In one embodiment, the process of preparing a planar TiO2 electron transport layer on a substrate is as follows: The substrate is cleaned, and the TiCl4 solution is slowly dripped into the ice obtained by freezing pure water. The ice-water mixture is then poured into a crystallization dish containing the substrate so that the liquid surface completely immerses the substrate. The substrate is placed in an oven for constant temperature reaction. After the reaction is completed, it is rinsed with deionized water for cooling, blown dry with nitrogen, and annealed in sequence to complete the preparation of the planar TiO2 electron transport layer. The heat treatment temperature is 80-120° C., and the heat treatment time is 2-5 minutes.
[0010] In one embodiment, the concentration of pyridine-3,5-dicarboxylic acid in the aqueous solution of the complex is 0.5 mg / mL to 1.5 mg / mL.
[0011] In one embodiment, the process of adding pyridine-3,5-dicarboxylic acid powder to an icy TiCl4 aqueous solution to prepare a complex aqueous solution and using the complex aqueous solution to prepare a pyridine-3,5-dicarboxylic acid-doped TiO2 electron transport layer on a substrate is as follows: The substrate is cleaned, and a TiCl4 solution is slowly dripped into ice obtained by freezing pure water to prepare a TiCl4 ice water solution; pyridine-3,5-dicarboxylic acid powder is added to the TiCl4 ice water solution to prepare a complex aqueous solution; The complex aqueous solution is poured into a crystallization dish containing a substrate so that the liquid surface completely submerges the substrate, and then placed in an oven for constant temperature reaction. After the reaction, it is rinsed with deionized water for cooling, dried with nitrogen, and annealed in sequence to complete the preparation of the pyridine-3,5-dicarboxylic acid-doped TiO2 electron transport layer.
[0012] In one embodiment, the preparation of CsPbI 3-x Br x The process of the perovskite light absorbing layer is as follows: Preparation of inorganic CsPbI 3-x Br x Precursor solution; Inorganic CsPbI 3-x Br x The precursor solution was added dropwise onto the pyridine-3,5-dicarboxylic acid modified layer or the pyridine-3,5-dicarboxylic acid doped TiO2 electron transport layer, and then spin-coated and heat-treated in sequence to obtain CsPbI 3-x Br x Perovskite light absorbing layer.
[0013] In one embodiment, the process for preparing the Spiro-OMeTAD hole transport layer is as follows: Spiro-OMeTAD was used as the hole transport layer material and chlorobenzene was used as the solvent. Spiro-OMeTAD was dissolved in chlorobenzene, and then a lithium salt acetonitrile solution and tBP were added to prepare a Spiro-OMeTAD solution. The Spiro-OMeTAD solution was added dropwise to the CsPbI 3-x Br x Spin coating is performed on the perovskite light absorption layer to complete the preparation of the Spiro-OMeTAD hole transport layer.
[0014] The present invention also provides a pyridine-3,5-dicarboxylic acid modified / doped all-inorganic perovskite solar cell prepared by the above-mentioned preparation method of the pyridine-3,5-dicarboxylic acid modified / doped all-inorganic perovskite solar cell, wherein the pyridine-3,5-dicarboxylic acid modified / doped all-inorganic perovskite solar cell includes a pyridine-3,5-dicarboxylic acid modified all-inorganic perovskite solar cell and a pyridine-3,5-dicarboxylic acid doped all-inorganic perovskite solar cell; The pyridine-3,5-dicarboxylic acid modified all-inorganic perovskite solar cell comprises a substrate, a planar TiO2 electron transport layer, a pyridine-3,5-dicarboxylic acid modified layer, a CsPbI 3-x Br x Perovskite light absorption layer, Spiro-OMeTAD hole transport layer and Ag electrode; The pyridine-3,5-dicarboxylic acid doped all-inorganic perovskite solar cell comprises a substrate, a pyridine-3,5-dicarboxylic acid doped TiO2 electron transport layer, a CsPbI 3-x Br x Perovskite light absorption layer, Spiro-OMeTAD hole transport layer and Ag electrode.
[0015] In one embodiment, the pyridine-3,5-dicarboxylic acid modified all-inorganic perovskite solar cell has an open circuit voltage of 0.94-0.97 V and a short circuit current of 18.43-19.70 mA / cm 2 , the fill factor is 68.19~73.42, and the photoelectric conversion efficiency is 11.86~14.05%; The open circuit voltage of the pyridine-3,5-dicarboxylic acid doped all-inorganic perovskite solar cell is 0.81-0.96 V, and the short circuit current is 16.48-19.63 mA / cm 2 , the filling factor is 68.19~74.30, and the photoelectric conversion efficiency is 9.14~14.00%.
[0016] Compared with the prior art, the present invention has the following beneficial effects: The present invention provides a preparation method for pyridine-3,5-dicarboxylic acid modified / doped all-inorganic perovskite solar cells. By optimizing the titanium dioxide electron transport layer with pyridine-3,5-dicarboxylic acid (5-CA), the bottleneck of existing technology is solved from three dimensions: molecular coordination mechanism, energy level regulation and interface stability. The lone pair electrons of the pyridine ring in the 5-CA molecule interact with the uncoordinated Pb in the perovskite. 2+ Forming N-Pb coordination bonds, directly passivating the lead vacancy defects on the interface; its dicarboxylic acid groups bind to the TiO2 surface through a bidentate chelation mode. 4+The combination forms a stable Ti-OCO-Ti bridge structure, reducing the density of oxygen vacancy defect states. The hydrogen bonding network also suppresses the redissolution reaction between the perovskite precursor and TiO2, improving film uniformity. In terms of energy band engineering, the LUMO energy level of 5-CA (-3.1 eV) is precisely embedded between the TiO2 conduction band (-4.3 eV) and the perovskite conduction band (-3.8 eV), creating a gradient energy level structure that reduces the interface barrier from 0.8 eV to 0.25 eV, improving electron mobility and reducing open-circuit voltage loss. Furthermore, the LUMO energy level characteristics of 5-CA are closely related to its molecular structure. The conjugated system of the pyridine ring and the electronic effect of the carboxylic acid group synergistically modulate the energy distribution of the molecular orbitals, enabling the LUMO energy level to form an effective charge transfer channel with TiO2 surface defects while maintaining energy alignment with the perovskite conduction band, thereby improving carrier extraction efficiency. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Figure 1 This is a structural diagram of the pyridine-3,5-dicarboxylic acid modified all-inorganic perovskite solar cell of the present invention; Figure 2 This is a structural diagram of the pyridine-3,5-dicarboxylic acid doped all-inorganic perovskite solar cell of the present invention; Figure 3 This is a JV curve diagram of the pyridine-3,5-dicarboxylic acid modified all-inorganic perovskite solar cell treated with different concentrations of pyridine-3,5-dicarboxylic acid of the present invention; Figure 4 JV curves of pyridine-3,5-dicarboxylic acid-doped all-inorganic perovskite solar cells treated with pyridine-3,5-dicarboxylic acid at different concentrations according to the present invention. DETAILED DESCRIPTION
[0018] To facilitate understanding of the features and effects of the present invention by those skilled in the art, the following provides a general description and definition of the terms and expressions used in the specification and claims. Unless otherwise indicated, all technical and scientific terms used herein have the ordinary meanings as understood by those skilled in the art regarding the present invention. In the event of conflict, the definitions in this specification shall prevail.
[0019] The theories or mechanisms described and disclosed herein, whether correct or incorrect, should not limit the scope of the present invention in any way, that is, the present invention can be implemented without being limited by any specific theory or mechanism.
[0020] All features, such as values, amounts, contents, and concentrations, described herein as numerical ranges or percentage ranges are provided for simplicity and convenience only. Accordingly, the description of numerical ranges or percentage ranges should be considered to include and specifically disclose all possible subranges and individual values within the range (including integers and fractions).
[0021] In this document, unless otherwise specified, “include,” “including,” “contains,” “has” or similar terms cover the meanings of “consisting of” and “mainly consisting of,” for example, “A includes a” covers the meanings of “A includes a and other” and “A only includes a.”
[0022] In this document, for the sake of brevity, not all possible combinations of the various technical features in each embodiment or example are described. Therefore, as long as there are no contradictions in the combination of these technical features, the various technical features in each embodiment or example can be combined in any way, and all possible combinations should be considered to be within the scope of this specification.
[0023] The pyridine-3,5-dicarboxylic acid (5-CA) used in the present invention was purchased from Aladdin with a specification of 98%. It is easy to absorb moisture and is sensitive to heat, light and air.
[0024] The present invention provides a method for preparing a pyridine-3,5-dicarboxylic acid modified / doped all-inorganic perovskite solar cell, comprising the following steps: A planar TiO2 electron transport layer is prepared on a substrate; pyridine-3,5-dicarboxylic acid powder is dissolved in DMF to prepare a pyridine-3,5-dicarboxylic acid solution; the pyridine-3,5-dicarboxylic acid solution is dropwise added onto the planar TiO2 electron transport layer and spin-coated, followed by heat treatment to achieve crystallization, thereby obtaining a pyridine-3,5-dicarboxylic acid modified layer; Alternatively, pyridine-3,5-dicarboxylic acid powder is added to a TiCl4 icy water solution to prepare a complex aqueous solution, and the complex aqueous solution is used to prepare a pyridine-3,5-dicarboxylic acid-doped TiO2 electron transport layer on a substrate; CsPbI was sequentially prepared on top of the pyridine-3,5-dicarboxylic acid modified layer or the pyridine-3,5-dicarboxylic acid doped TiO2 electron transport layer. 3-x Br x A perovskite light absorption layer, a Spiro-OMeTAD hole transport layer, and then a layer of Ag electrode evaporated on the top to produce a pyridine-3,5-dicarboxylic acid modified / doped all-inorganic perovskite solar cell.
[0025] Among them, preparation of CsPbI 3-x Br x The process of the perovskite light absorbing layer is as follows: Preparation of inorganic CsPbI 3-x Br x Precursor solution; Inorganic CsPbI 3-x Br xThe precursor solution was added dropwise onto the pyridine-3,5-dicarboxylic acid modified layer or the pyridine-3,5-dicarboxylic acid doped TiO2 electron transport layer, and then spin-coated and heat-treated in sequence to obtain CsPbI 3-x Br x Perovskite light absorbing layer.
[0026] The process of preparing the Spiro-OMeTAD hole transport layer is as follows: Spiro-OMeTAD was used as the hole transport layer material and chlorobenzene was used as the solvent. Spiro-OMeTAD was dissolved in chlorobenzene, and then a lithium salt acetonitrile solution and tBP were added to prepare a Spiro-OMeTAD solution. The Spiro-OMeTAD solution was added dropwise to the CsPbI 3-x Br x Spin coating is performed on the perovskite light absorption layer to complete the preparation of the Spiro-OMeTAD hole transport layer.
[0027] The present invention provides a method for preparing a pyridine-3,5-dicarboxylic acid modified all-inorganic perovskite solar cell, comprising the following steps: preparing a planar TiO2 electron transport layer on a substrate; Dissolving pyridine-3,5-dicarboxylic acid powder in DMF to prepare a pyridine-3,5-dicarboxylic acid solution; A pyridine-3,5-dicarboxylic acid solution is added dropwise on the planar TiO2 electron transport layer and spin-coated, followed by heat treatment to complete crystallization, thereby obtaining a pyridine-3,5-dicarboxylic acid modified layer; CsPbI was prepared on top of the pyridine-3,5-dicarboxylic acid modified layer. 3-x Br x A perovskite light absorption layer, a Spiro-OMeTAD hole transport layer, and then a layer of Ag electrode evaporated on the top to prepare a pyridine-3,5-dicarboxylic acid modified all-inorganic perovskite solar cell.
[0028] The process of preparing a planar TiO2 electron transport layer on a substrate is as follows: Clean the substrate, slowly drip 2.25 mL of TiCl4 solution into the ice obtained by freezing 100 mL of pure water, then pour the ice-water mixture into the crystallization dish containing the substrate so that the liquid surface completely immerses the substrate, and place it in an oven for constant temperature reaction. After the reaction is completed, rinse with deionized water for cooling, blow dry with nitrogen, and anneal to complete the preparation of the planar TiO2 electron transport layer.
[0029] The concentration of the pyridine-3,5-dicarboxylic acid solution is 25 mg / mL to 100 mg / mL.
[0030] The spin coating is a two-stage step-by-step process: the first stage is a low-speed spin coating at 500-1500 rpm for 5-10 seconds, and the second stage is a high-speed spin coating at 3000-5000 rpm for 20-30 seconds. The heat treatment temperature is 80-120°C, and the heat treatment time is 2-5 minutes.
[0031] See also Figure 1 The present invention also provides a pyridine-3,5-dicarboxylic acid modified all-inorganic perovskite solar cell prepared by the above-mentioned preparation method of pyridine-3,5-dicarboxylic acid modified all-inorganic perovskite solar cell, which comprises a substrate, a planar TiO2 electron transport layer, a pyridine-3,5-dicarboxylic acid modified layer, a CsPbI 3-x Br x It consists of a perovskite light absorption layer, a Spiro-OMeTAD hole transport layer and an Ag electrode.
[0032] The open-circuit voltage of the pyridine-3,5-dicarboxylic acid modified all-inorganic perovskite solar cell is 0.94-0.97 V, and the short-circuit current is 18.43-19.70 mA / cm 2 , the filling factor is 68.19~73.42, and the photoelectric conversion efficiency is 11.86~14.05%.
[0033] The present invention also provides a method for preparing a pyridine-3,5-dicarboxylic acid-doped all-inorganic perovskite solar cell, comprising the following steps: adding pyridine-3,5-dicarboxylic acid powder into TiCl4 icy water solution to prepare a complex aqueous solution, and using the complex aqueous solution to prepare a pyridine-3,5-dicarboxylic acid-doped TiO2 electron transport layer on a substrate; CsPbI was prepared on top of the pyridine-3,5-dicarboxylic acid doped TiO2 electron transport layer. 3-x Br x A perovskite light absorption layer, a Spiro-OMeTAD hole transport layer, and then a layer of Ag electrode evaporated on the top to produce a pyridine-3,5-dicarboxylic acid-doped all-inorganic perovskite solar cell.
[0034] The process of adding pyridine-3,5-dicarboxylic acid powder to TiCl4 icy water solution to prepare a complex aqueous solution and using the complex aqueous solution to prepare a pyridine-3,5-dicarboxylic acid-doped TiO2 electron transport layer on a substrate is as follows: The substrate was cleaned, and 2.25 mL of TiCl4 solution was slowly dripped into ice obtained by freezing 100 mL of pure water to prepare a TiCl4 ice-water solution; pyridine-3,5-dicarboxylic acid powder was added to the TiCl4 ice-water solution to prepare an aqueous solution of the complex; The complex aqueous solution is poured into a crystallization dish containing a substrate so that the liquid surface completely submerges the substrate, and then placed in an oven for constant temperature reaction. After the reaction, it is rinsed with deionized water for cooling, dried with nitrogen, and annealed in sequence to complete the preparation of the pyridine-3,5-dicarboxylic acid-doped TiO2 electron transport layer.
[0035] The concentration of pyridine-3,5-dicarboxylic acid in the aqueous solution of the complex is 0.5 mg / mL to 1.5 mg / mL.
[0036] See also Figure 2 The present invention also provides a pyridine-3,5-dicarboxylic acid doped all-inorganic perovskite solar cell prepared by the above-mentioned preparation method of pyridine-3,5-dicarboxylic acid doped all-inorganic perovskite solar cell, which comprises a substrate, a pyridine-3,5-dicarboxylic acid doped TiO2 electron transport layer, a CsPbI 3-x Br x It consists of a perovskite light absorption layer, a Spiro-OMeTAD hole transport layer and an Ag electrode.
[0037] The open-circuit voltage of the pyridine-3,5-dicarboxylic acid-doped all-inorganic perovskite solar cell is 0.81-0.96 V, and the short-circuit current is 16.48-19.63 mA / cm 2 , the filling factor is 68.19~74.30, and the photoelectric conversion efficiency is 9.14~14.00%.
[0038] Below in conjunction with specific embodiment, further set forth the present invention.Should be understood that these embodiments are only used to illustrate the present invention and are not used in limiting the scope of the present invention.In addition, should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms fall equally within the scope limited by the appended claims of the application.
[0039] The following examples were prepared using conventional instruments and equipment in the art. Experimental methods in the following examples, where specific conditions are not specified, were generally performed under conventional conditions or according to the conditions recommended by the manufacturer. The various raw materials used in the following examples, unless otherwise specified, were conventional commercially available products, with specifications conventional in the art. In the present specification and the following examples, unless otherwise specified, "%" indicates percentage by weight, "part" indicates parts by weight, and "ratio" indicates weight ratio.
[0040] Example 1 This embodiment provides a method for preparing a pyridine-3,5-dicarboxylic acid modified all-inorganic perovskite solar cell, comprising the following steps: (1) Preparation of dense planar TiO2 electron transport layer First, a FTO glass (2.47 cm × 2.47 cm) was ultrasonically cleaned for 30 minutes using detergent, pure water, acetone, isopropanol, and ethanol, sequentially. After cleaning, it was dried with nitrogen. Next, 2.25 mL of TiCl₄ solution was slowly dripped into ice obtained by freezing 100 mL of pure water. The mixture was allowed to cool for 20 minutes. While the ice melted, the crystallization dish was cleaned with detergent and a test tube brush and dried in a vacuum drying oven for 20 minutes. The dried FTO glass was then UV-bombarded for 5 minutes and secured to the crystallization dish with insulating tape. When the ice was almost completely melted, the ice-water mixture was poured into the crystallization dish containing the FTO glass, ensuring that the liquid surface completely submerged the FTO glass. Finally, the crystallization dish was placed in a 60°C oven for 60 minutes. After reaction, the reaction solution was quickly discarded and rinsed with copious amounts of deionized water until it cooled to room temperature. After complete cooling, the dish was dried with nitrogen. The annealing table was preheated to 200°C and annealed for one hour.
[0041] (2) Preparation of pyridine-3,5-dicarboxylic acid solution Weigh 25 mg of pyridine-3,5-dicarboxylic acid powder on a balance and place it in a solution bottle. Then, add 1 mL of DMF to the solution bottle. Add a magnet and stir with a magnetic stirrer for several hours to prepare a 25 mg / mL pyridine-3,5-dicarboxylic acid solution.
[0042] (3) Preparation of pyridine-3,5-dicarboxylic acid modified layer The prepared FTO substrate with a TiO2 electron transport layer was first treated with UV radiation for 1 minute. Then, within an N2 glove box, the treated substrate was placed on a spin coater. 35 μL of the prepared pyridine-3,5-dicarboxylic acid solution was dripped onto the substrate, evenly covering it. The spin coating process was selected: the first stage was a 10-second cycle at 1000 rpm, and the second stage was a 30-second cycle at 4000 rpm. The pre-prepared film was heat-treated on a 100°C hot plate for 3 minutes to complete crystallization, resulting in a pyridine-3,5-dicarboxylic acid modified layer.
[0043] (4) Inorganic CsPbI 3-x Br x Preparation of precursor solution Weigh DMAPbI₃ (0.38 g), CsI (0.19 g), and PbBr₂ (0.07 g) using a balance and place them in a solution bottle. Then, prepare a 9:1 solvent mixture of DMF and DMSO. Add 1 mL of this solvent mixture to the weighed mixture. Add a magnetic stir bar and stir at room temperature for several hours until a pale yellow solution is obtained.
[0044] (5) Perovskite absorber layer CsPbI3-x Br x Preparation First, a prepared FTO substrate with pyridine-3,5-dicarboxylic acid-modified TiO2 was placed on a spin coater. 45 μL of the prepared perovskite precursor solution was dripped onto it, evenly covering the substrate. The spin coating process was selected: the first stage was a 10-second working time at 1000 rpm, and the second stage was a 40-second working time at 4500 rpm. The pre-prepared film was heat-treated on a 200°C hot plate for 5 minutes to complete crystallization, thus forming the perovskite light-absorbing layer.
[0045] (6) Preparation of hole transport layer solution Spiro-OMeTAD was selected as the hole transport layer material, and the preparation formula was as follows: 0.072 g of Spiro-OMeTAD powder produced by Xi'an Baolait was weighed and chlorobenzene was selected as the solvent, which was dissolved in 1 mL of chlorobenzene. Subsequently, 18 μL of acetonitrile solution with a concentration of 0.52 g / mL lithium salt and 36 μL of tBP were added, and finally stirred for 10 h to obtain the prepared Spiro-OMeTAD solution.
[0046] (7) Preparation of hole transport layer First, in FTO / TiO2 / 5-CA / Perovskite(CsPbI 3-x Br x ) was evenly dripped with 45 μL of Spiro-OMeTAD solution, and then a spin coating process at 4000 rpm was used to prepare the Spiro-OMeTAD hole transport layer to obtain FTO / TiO2 / 5-CA / Perovskite(CsPbI 3-x Br x ) / Structure of Spiro-OMeTAD.
[0047] (8) Evaporation of silver electrodes Using high vacuum thermal evaporation technology, a layer of Ag electrode with a thickness of about 70 nm was deposited on the top of the film using a metal thermal evaporation system. A mask was used during the deposition to ensure that the effective area of the device was 0.09 cm 2 .
[0048] The structure of the pyridine-3,5-dicarboxylic acid modified all-inorganic perovskite solar cell prepared in this embodiment is as follows: Figure 1 As shown, from bottom to top, it consists of a glass substrate, a planar TiO2 electron transport layer, a pyridine-3,5-dicarboxylic acid modified layer, and a CsPbI 3- x Br xIt consists of a perovskite light absorption layer, a Spiro-OMeTAD hole transport layer and an Ag electrode.
[0049] Example 2 The difference between this embodiment and embodiment 1 is that in step (2), the preparation of pyridine-3,5-dicarboxylic acid solution is Weigh 50 mg of pyridine-3,5-dicarboxylic acid powder using a balance and place it in a solution bottle. Subsequently, add 1 mL of DMF to the solution bottle, add a magnet, and stir with a magnetic stirrer for several hours to prepare a 50 mg / mL pyridine-3,5-dicarboxylic acid solution.
[0050] The structure of the pyridine-3,5-dicarboxylic acid modified all-inorganic perovskite solar cell prepared in this embodiment is as follows: Figure 1 As shown, from bottom to top, it consists of a glass substrate, a planar TiO2 electron transport layer, a pyridine-3,5-dicarboxylic acid modified layer, and a CsPbI 3- x Br x It consists of a perovskite light absorption layer, a Spiro-OMeTAD hole transport layer and an Ag electrode.
[0051] Example 3 The difference between this embodiment and embodiment 1 is that in step (2), the preparation of pyridine-3,5-dicarboxylic acid solution is Weigh 100 mg of pyridine-3,5-dicarboxylic acid powder using a balance and place it in a solution bottle. Subsequently, add 1 mL of DMF to the solution bottle. Add a magnet and stir with a magnetic stirrer for several hours to prepare a 100 mg / mL pyridine-3,5-dicarboxylic acid solution.
[0052] The structure of the pyridine-3,5-dicarboxylic acid modified all-inorganic perovskite solar cell prepared in this embodiment is as follows: Figure 1 As shown, from bottom to top, it consists of a glass substrate, a planar TiO2 electron transport layer, a pyridine-3,5-dicarboxylic acid modified layer, and a CsPbI 3- x Br x It consists of a perovskite light absorption layer, a Spiro-OMeTAD hole transport layer and an Ag electrode.
[0053] The main performance parameters of perovskite solar cells at different pyridine-3,5-dicarboxylic acid concentrations are shown in Table 1. When the pyridine-3,5-dicarboxylic acid concentration is 50 mg / mL, the open circuit voltage of the device is 0.97 V and the short circuit current is 19.70 mA / cm 2 , the filling factor is 73.42, the photoelectric conversion efficiency is 14.05%, and the JV curve is as follows Figure 3As the concentration of pyridine-3,5-dicarboxylic acid increases, the efficiency of the perovskite solar cell increases until it reaches 50 mg / mL, where the photoelectric conversion efficiency is the highest. When the concentration reaches 100 mg / mL, the efficiency begins to decrease.
[0054] The present invention significantly improves the open circuit voltage, short circuit current density, fill factor and photoelectric conversion efficiency of the all-inorganic perovskite solar cell by trying additives of different concentrations.
[0055] Table 1 Main performance parameters of perovskite solar cells modified with different pyridine-3,5-dicarboxylic acid concentrations
[0056] Example 4 The difference between this embodiment and embodiment 1 is that in step (3), the preparation of the pyridine-3,5-dicarboxylic acid modified layer The prepared FTO substrate with a TiO2 electron transport layer was first treated with UV radiation for 1 minute. Then, in an N2 glove box, the treated substrate was placed on a spin coater. 35 μL of the prepared pyridine-3,5-dicarboxylic acid solution was dripped onto the substrate, evenly covering it. The spin coating process was selected: the first stage was 10 seconds at 500 rpm, and the second stage was 30 seconds at 3000 rpm. The pre-prepared film was heat-treated on a 120°C hot plate for 2 minutes to complete crystallization, resulting in a pyridine-3,5-dicarboxylic acid modified layer.
[0057] The structure of the pyridine-3,5-dicarboxylic acid modified all-inorganic perovskite solar cell prepared in this embodiment is as follows: Figure 1 As shown, from bottom to top, it consists of a glass substrate, a planar TiO2 electron transport layer, a pyridine-3,5-dicarboxylic acid modified layer, and a CsPbI 3- x Br x It consists of a perovskite light absorption layer, a Spiro-OMeTAD hole transport layer and an Ag electrode.
[0058] Example 5 The difference between this embodiment and embodiment 1 is that in step (3), the preparation of the pyridine-3,5-dicarboxylic acid modified layer The prepared FTO substrate with a TiO2 electron transport layer was first treated with UV radiation for 1 minute. Then, in an N2 glove box, the treated substrate was placed on a spin coater. 35 μL of the prepared pyridine-3,5-dicarboxylic acid solution was dripped onto the substrate, evenly covering it. The spin coating process was selected: the first stage was a 5-second operation at 1500 rpm, and the second stage was a 20-second operation at 5000 rpm. The pre-prepared film was heat-treated on an 80°C hot plate for 5 minutes to complete crystallization, resulting in a pyridine-3,5-dicarboxylic acid modified layer.
[0059] The structure of the pyridine-3,5-dicarboxylic acid modified all-inorganic perovskite solar cell prepared in this embodiment is as follows: Figure 1 As shown, from bottom to top, it consists of a glass substrate, a planar TiO2 electron transport layer, a pyridine-3,5-dicarboxylic acid modified layer, and a CsPbI 3- x Br x It consists of a perovskite light absorption layer, a Spiro-OMeTAD hole transport layer and an Ag electrode.
[0060] In summary, pyridine-3,5-dicarboxylic acid is used to modify the electron transport layer. Pyridine-3,5-dicarboxylic acid (5-CA) has a dual-functional coordination mechanism, a unique 5-CA gradient energy level design and interface barrier regulation, and pyridine-3,5-dicarboxylic acid is used as an additive to prepare all-inorganic perovskite solar cells. 3-X Br X As a perovskite light-absorbing layer material, this method differs from the preparation methods of organic-inorganic hybrid perovskite solar cells and inverted lead-free perovskite solar cells. Furthermore, the present invention improves the photoelectric conversion efficiency of perovskite solar cells by adding different concentrations of pyridine-3,5-dicarboxylic acid solution between the electron transport layer and the perovskite layer. A 50 mg / mL pyridine-3,5-dicarboxylic acid solution exhibits the best effect.
[0061] Example 6 This embodiment provides a method for preparing a pyridine-3,5-dicarboxylic acid-doped all-inorganic perovskite solar cell, comprising the following steps: (1) Preparation of dense planar 35CA-TiO2 electron transport layer, i.e., pyridine-3,5-dicarboxylic acid-doped TiO2 electron transport layer First, FTO glass (2.47 cm × 2.47 cm) was ultrasonically cleaned for 30 min using deionized water, isopropanol, acetone, and ethanol, respectively. After washing, it was dried with nitrogen. Then, 2.25 mL of TiCl₄ solution was slowly dripped into ice obtained by freezing 100 mL of deionized water. After waiting for 20 min, a TiCl₄ ice-water solution was prepared. Accurately weighed 35CA-dicarboxylic acid powder was added to the solution and stirred with a glass rod for 5 min to prepare a transparent aqueous solution of the complex. The concentration of pyridine-3,5-dicarboxylic acid in the aqueous solution of the complex was 0.5 mg / mL. While waiting for the ice to melt, the crystallization dish was cleaned with detergent and a test tube brush and dried in a high-grade oven for 20 min. The dried FTO glass was UV-bombarded for 5 min and fixed to the crystallization dish with insulating tape. When the ice was about to melt completely, the aqueous solution of the complex was poured into the crystallization dish containing the FTO glass so that the liquid surface completely submerged the FTO glass. Finally, place the crystallization dish in a 60°C oven for constant temperature reaction for 60 minutes, then take it out, quickly pour out the reaction solution and rinse with a large amount of deionized water until it cools to room temperature. After it is completely cooled, blow it dry with nitrogen, preheat the annealing table to 200°C, and anneal for one hour.
[0062] (2) Inorganic CsPbI 3-x Br x Preparation of precursor solution Weigh DMAPbI₃ (0.38 g), CsI (0.19 g), and PbBr₂ (0.07 g) using a balance and place them in a solution bottle. Then, prepare a 9:1 solvent mixture of DMF and DMSO. Add 1 mL of this solvent mixture to the weighed mixture. Add a magnetic stir bar and stir at room temperature for several hours until a pale yellow solution is obtained.
[0063] (3) Perovskite absorber layer CsPbI 3-x Br x Preparation First, a pre-prepared FTO substrate with a pyridine-3,5-dicarboxylic acid-doped TiO2 electron transport layer was placed on a spin coater. 45 μL of the prepared perovskite precursor solution was dripped onto the substrate, evenly covering it. The spin coating process was selected: the first stage was a 10-second working time at 1000 rpm, and the second stage was a 40-second working time at 4500 rpm. The pre-prepared film was heat-treated on a 200°C hot plate for 5 minutes to complete crystallization, resulting in the perovskite light-absorbing layer.
[0064] (6) Preparation of hole transport layer solution Spiro-OMeTAD was selected as the hole transport layer material, and the preparation formula was as follows: 0.072 g of Spiro-OMeTAD powder produced by Xi'an Baolait was weighed and chlorobenzene was selected as the solvent, which was dissolved in 1 mL of chlorobenzene. Subsequently, 18 μL of acetonitrile solution with a concentration of 0.52 g / mL lithium salt and 36 μL of tBP were added, and finally stirred for 10 h to obtain the prepared Spiro-OMeTAD solution.
[0065] (7) Preparation of hole transport layer First, in FTO / 35CA-TiO2 / Perovskite(CsPbI 3-x Br x ) was evenly dripped with 45 μL of Spiro-OMeTAD solution, and then the Spiro-OMeTAD hole transport layer was prepared by spin coating at a speed of 4000 rpm to obtain FTO / 35CA-TiO2 / Perovskite(CsPbI 3-x Br x ) / Structure of Spiro-OMeTAD.
[0066] (8) Evaporation of silver electrodes Using high vacuum thermal evaporation technology, a layer of Ag electrode with a thickness of about 70 nm was deposited on the top of the film using a metal thermal evaporation system. A mask was used during the deposition to ensure that the effective area of the device was 0.09 cm 2 .
[0067] The structure of the pyridine-3,5-dicarboxylic acid doped all-inorganic perovskite solar cell prepared in this embodiment is as follows: Figure 2 As shown, from bottom to top, the substrate, pyridine-3,5-dicarboxylic acid doped TiO2 electron transport layer, CsPbI 3-x Br x It consists of a perovskite light absorption layer, a Spiro-OMeTAD hole transport layer and an Ag electrode.
[0068] Example 7 The difference between this embodiment and embodiment 6 is that step (1) preparation of a dense planar 35CA-TiO2 electron transport layer, i.e., a pyridine-3,5-dicarboxylic acid doped TiO2 electron transport layer First, FTO glass (2.47 cm × 2.47 cm) was ultrasonically cleaned for 30 min using deionized water, isopropanol, acetone, and ethanol, respectively. After washing, it was dried with nitrogen. Then, 2.25 mL of TiCl₄ solution was slowly dripped into ice obtained by freezing 100 mL of deionized water. After waiting for 20 min, a TiCl₄ ice-water solution was prepared. Accurately weighed 35CA-dicarboxylic acid powder was added to the solution and stirred with a glass rod for 5 min to prepare a transparent aqueous solution of the complex. The concentration of pyridine-3,5-dicarboxylic acid in the aqueous solution of the complex was 1 mg / mL. While waiting for the ice to melt, the crystallization dish was cleaned with detergent and a test tube brush and dried in a high-grade oven for 20 min. The dried FTO glass was UV-bombarded for 5 min and fixed to the crystallization dish with insulating tape. When the ice was about to melt completely, the aqueous solution of the complex was poured into the crystallization dish containing the FTO glass so that the liquid surface completely submerged the FTO glass. Finally, place the crystallization dish in a 60°C oven for constant temperature reaction for 60 minutes, then take it out, quickly pour out the reaction solution and rinse with a large amount of deionized water until it cools to room temperature. After it is completely cooled, blow it dry with nitrogen, preheat the annealing table to 200°C, and anneal for one hour.
[0069] Example 8 The difference between this embodiment and embodiment 6 is that step (1) preparation of a dense planar 35CA-TiO2 electron transport layer, i.e., a pyridine-3,5-dicarboxylic acid doped TiO2 electron transport layer First, FTO glass (2.47 cm × 2.47 cm) was ultrasonically cleaned for 30 min using deionized water, isopropanol, acetone, and ethanol, respectively. After washing, it was dried with nitrogen. Then, 2.25 mL of TiCl₄ solution was slowly dripped into ice obtained by freezing 100 mL of deionized water. After waiting for 20 min, a TiCl₄ ice-water solution was prepared. Accurately weighed 35CA-dicarboxylic acid powder was added to the solution and stirred with a glass rod for 5 min to prepare a transparent aqueous solution of the complex. The concentration of pyridine-3,5-dicarboxylic acid in the aqueous solution of the complex was 1.5 mg / mL. While waiting for the ice to melt, the crystallization dish was cleaned with detergent and a test tube brush and dried in a high-grade oven for 20 min. The dried FTO glass was UV-bombarded for 5 min and fixed to the crystallization dish with insulating tape. When the ice was about to melt completely, the aqueous solution of the complex was poured into the crystallization dish containing the FTO glass so that the liquid surface completely submerged the FTO glass. Finally, place the crystallization dish in a 60°C oven for constant temperature reaction for 60 minutes, then take it out, quickly pour out the reaction solution and rinse with a large amount of deionized water until it cools to room temperature. After it is completely cooled, blow it dry with nitrogen, preheat the annealing table to 200°C, and anneal for one hour.
[0070] Table 2 Main performance parameters of perovskite solar cells doped with different pyridine-3,5-dicarboxylic acid concentrations
[0071] In summary, pyridine-3,5-dicarboxylic acid is used to dope the electron transport layer. As an organic molecule, pyridine-3,5-dicarboxylic acid can interact with the TiO2 surface, improving electron migration and transport efficiency, reducing carrier recombination at the interface, and increasing electron mobility between the perovskite layer and the electron transport layer. The incorporation of pyridine-3,5-dicarboxylic acid helps optimize the contact between the perovskite and TiO2 interfaces, enhance their compatibility, and reduce interfacial defects. Interfacial defects are often the primary source of carrier recombination. Improving the interface structure can effectively reduce this recombination phenomenon, thereby increasing the open-circuit voltage (Voc) and fill factor (FF) of the cell. With improved electron transport performance and interface quality, the power conversion efficiency (PCE) of the solar cell is typically significantly enhanced. Doping the TiO2 electron transport layer helps enhance carrier collection efficiency and reduce energy losses, further improving the overall efficiency of perovskite solar cells. The present invention improves the photoelectric conversion efficiency of perovskite solar cells by doping pyridine-3,5-dicarboxylic acid solutions of different concentrations during the preparation of the electron transport layer. Among them, a pyridine-3,5-dicarboxylic acid solution with a concentration of 1 mg / mL has the best effect.
[0072] The above content is only for explaining the technical idea of the present invention and cannot be used to limit the protection scope of the present invention. Any changes made on the basis of the technical solution in accordance with the technical idea proposed by the present invention shall fall within the protection scope of the claims of the present invention.
Claims
1. A method for preparing a pyridine-3,5-dicarboxylic acid modified / doped all-inorganic perovskite solar cell, characterized in that: The following steps are involved: A planar TiO2 electron transport layer is prepared on a substrate; pyridine-3,5-dicarboxylic acid powder is dissolved in DMF to prepare a pyridine-3,5-dicarboxylic acid solution; the pyridine-3,5-dicarboxylic acid solution is dropwise added onto the planar TiO2 electron transport layer and spin-coated, followed by heat treatment to achieve crystallization, thereby obtaining a pyridine-3,5-dicarboxylic acid modified layer; Alternatively, pyridine-3,5-dicarboxylic acid powder is added to a TiCl4 icy water solution to prepare a complex aqueous solution, and the complex aqueous solution is used to prepare a pyridine-3,5-dicarboxylic acid-doped TiO2 electron transport layer on a substrate; CsPbI was sequentially prepared on top of the pyridine-3,5-dicarboxylic acid modified layer or the pyridine-3,5-dicarboxylic acid doped TiO2 electron transport layer. 3-x Br x A perovskite light absorption layer, a Spiro-OMeTAD hole transport layer, and then a layer of Ag electrode evaporated on the top to produce a pyridine-3,5-dicarboxylic acid modified / doped all-inorganic perovskite solar cell.
2. The method for preparing a pyridine-3,5-dicarboxylic acid modified / doped all-inorganic perovskite solar cell according to claim 1, wherein: The concentration of the pyridine-3,5-dicarboxylic acid solution is 25 mg / mL to 100 mg / mL.
3. The method for preparing a pyridine-3,5-dicarboxylic acid modified / doped all-inorganic perovskite solar cell according to claim 1, wherein: The spin coating is a two-stage step-type spin coating, wherein the first stage is a low-speed spin coating at 500-1500 rpm for 5-10 s, and the second stage is a high-speed spin coating at 3000-5000 rpm for 20-30 s.
4. The method for preparing a pyridine-3,5-dicarboxylic acid modified / doped all-inorganic perovskite solar cell according to claim 1, characterized in that: The process of preparing a planar TiO2 electron transport layer on a substrate is as follows: The substrate is cleaned, and the TiCl4 solution is slowly dripped into the ice obtained by freezing pure water. The ice-water mixture is then poured into a crystallization dish containing the substrate so that the liquid surface completely immerses the substrate. The substrate is placed in an oven for constant temperature reaction. After the reaction is completed, it is rinsed with deionized water for cooling, blown dry with nitrogen, and annealed in sequence to complete the preparation of the planar TiO2 electron transport layer. The heat treatment temperature is 80-120° C., and the heat treatment time is 2-5 minutes.
5. The method for preparing a pyridine-3,5-dicarboxylic acid modified / doped all-inorganic perovskite solar cell according to claim 1, wherein: The concentration of pyridine-3,5-dicarboxylic acid in the aqueous complex solution is 0.5 mg / mL to 1.5 mg / mL.
6. The method for preparing a pyridine-3,5-dicarboxylic acid modified / doped all-inorganic perovskite solar cell according to claim 1, characterized in that: The process of adding pyridine-3,5-dicarboxylic acid powder to TiCl4 icy water solution to prepare a complex aqueous solution, and using the complex aqueous solution to prepare a pyridine-3,5-dicarboxylic acid-doped TiO2 electron transport layer on a substrate is as follows: The substrate is cleaned, and a TiCl4 solution is slowly dripped into ice obtained by freezing pure water to prepare a TiCl4 ice water solution; pyridine-3,5-dicarboxylic acid powder is added to the TiCl4 ice water solution to prepare a complex aqueous solution; The complex aqueous solution is poured into a crystallization dish containing a substrate so that the liquid surface completely submerges the substrate, and then placed in an oven for constant temperature reaction. After the reaction, it is rinsed with deionized water for cooling, dried with nitrogen, and annealed in sequence to complete the preparation of the pyridine-3,5-dicarboxylic acid-doped TiO2 electron transport layer.
7. The method for preparing a pyridine-3,5-dicarboxylic acid modified / doped all-inorganic perovskite solar cell according to claim 1, characterized in that: The preparation of CsPbI 3-x Br x The process of the perovskite light absorbing layer is as follows: Preparation of inorganic CsPbI 3-x Br x Precursor solution; Inorganic CsPbI 3-x Br x The precursor solution was added dropwise onto the pyridine-3,5-dicarboxylic acid modified layer or the pyridine-3,5-dicarboxylic acid doped TiO2 electron transport layer, and then spin-coated and heat-treated in sequence to obtain CsPbI 3-x Br x Perovskite light absorbing layer.
8. The method for preparing a pyridine-3,5-dicarboxylic acid modified / doped all-inorganic perovskite solar cell according to claim 1, characterized in that: The process of preparing the Spiro-OMeTAD hole transport layer is as follows: Spiro-OMeTAD was used as the hole transport layer material and chlorobenzene was used as the solvent. Spiro-OMeTAD was dissolved in chlorobenzene, and then a lithium salt acetonitrile solution and tBP were added to prepare a Spiro-OMeTAD solution. The Spiro-OMeTAD solution was added dropwise to the CsPbI 3-x Br x Spin coating is performed on the perovskite light absorption layer to complete the preparation of the Spiro-OMeTAD hole transport layer.
9. A pyridine-3,5-dicarboxylic acid modified / doped all-inorganic perovskite solar cell prepared by the method for preparing a pyridine-3,5-dicarboxylic acid modified / doped all-inorganic perovskite solar cell according to any one of claims 1 to 8, characterized in that: Pyridine-3,5-dicarboxylic acid modified / doped all-inorganic perovskite solar cells include pyridine-3,5-dicarboxylic acid modified all-inorganic perovskite solar cells and pyridine-3,5-dicarboxylic acid doped all-inorganic perovskite solar cells; The pyridine-3,5-dicarboxylic acid modified all-inorganic perovskite solar cell comprises a substrate, a planar TiO2 electron transport layer, a pyridine-3,5-dicarboxylic acid modified layer, a CsPbI 3-x Br x Perovskite light absorption layer, Spiro-OMeTAD hole transport layer and Ag electrode; The pyridine-3,5-dicarboxylic acid doped all-inorganic perovskite solar cell comprises a substrate, a pyridine-3,5-dicarboxylic acid doped TiO2 electron transport layer, a CsPbI 3-x Br x Perovskite light absorption layer, Spiro-OMeTAD hole transport layer and Ag electrode.
10. The pyridine-3,5-dicarboxylic acid modified / doped all-inorganic perovskite solar cell according to claim 9, characterized in that The open circuit voltage of the pyridine-3,5-dicarboxylic acid modified all-inorganic perovskite solar cell is 0.94-0.97 V, and the short circuit current is 18.43-19.70 mA / cm 2 , the fill factor is 68.19~73.42, and the photoelectric conversion efficiency is 11.86~14.05%; The open circuit voltage of the pyridine-3,5-dicarboxylic acid doped all-inorganic perovskite solar cell is 0.81-0.96 V, and the short circuit current is 16.48-19.63 mA / cm 2 , the filling factor is 68.19~74.30, and the photoelectric conversion efficiency is 9.14~14.00%.