Preparation method of tin oxide film, tin oxide film, solar cell and photovoltaic module
By using compound of formula I as a tin source, the reaction effect between the tin source and the oxygen source is improved, the problem of uneven tin oxide film thickness is solved, and the performance of solar cells is enhanced.
Patent Information
- Application Number
- CN202410872931.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-01
- Publication Date
- 2025-11-25
AI Technical Summary
The existing tin source has poor hydrophilicity, which leads to poor reaction between the tin source and the oxygen source, resulting in uneven thickness of the tin oxide film and affecting the performance of solar cells.
Using the compound of Formula I as the tin source, tin oxide films are prepared by atomic layer deposition. The hydrogen atoms in the compound of Formula I that are connected to the N atom can form hydrogen bonds, exhibiting strong hydrophilicity and low steric hindrance, which makes it easier for the tin source and oxygen source to be uniformly adsorbed and reacted, thus improving the uniformity of film thickness.
It effectively reduces atomic defects in tin oxide films, improves film thickness uniformity, enhances the fill factor and open-circuit voltage of solar cells, and improves energy conversion efficiency.
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Figure CN121006522A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of solar cells, and more particularly to a method for preparing a tin oxide film, as well as the tin oxide film, solar cell, and photovoltaic module. Background Technology
[0002] Tin sources are precursor sources for atomic layer deposition (ALD) in the preparation of tin oxide films. For example, in the process of preparing tin oxide films by ALD, tetrakis(dimethylamino)tin is used as a tin source to react chemically with an oxygen source to obtain tin oxide films. However, the existing tin sources have poor hydrophilicity, resulting in poor reaction between the tin source and the oxygen source, and the obtained tin oxide films have uneven thickness, which urgently needs further improvement. Summary of the Invention
[0003] To address the aforementioned technical problems, this application provides a method for preparing a tin oxide film, a tin oxide film, a solar cell, and a photovoltaic module, in order to improve the thickness uniformity of the tin oxide film and thereby improve the performance of the solar cell.
[0004] In a first aspect, embodiments of this application provide a method for preparing a tin oxide film.
[0005] A method for preparing a tin oxide film, comprising:
[0006] The tin oxide film is deposited on the substrate surface using atomic layer deposition (ALD) with a tin source and an oxygen source acting on the reactants. The tin source includes a compound of formula I:
[0007] In the compound of formula I, n = 1, 2, 3, 4.
[0008] As an optional implementation, in the embodiments of this application, the compound of formula I is selected from at least one of the following compounds:
[0009]
[0010] As an optional implementation, in the embodiments of this application, the preparation method of the compound of formula I is as follows: alkyl primary amine and tin tetrachloride are refluxed in a solvent in the presence of an organolithium catalyst to obtain the compound of formula I.
[0011] As an optional implementation, in the embodiments of this application, the alkyl primary amine includes methylamine, ethylamine, propylamine, isopropylamine and / or butylamine; and / or, the organolithium catalyst includes one or more combinations of methyllithium, n-butyllithium and phenyllithium; and / or, the solvent includes one or more combinations of anhydrous diethyl ether, tetrahydrofuran, anhydrous toluene and hexane.
[0012] As an optional implementation, in the embodiments of this application, the dose-time ratio of the tin source to the oxygen source is 1 to 100:1.
[0013] As an optional implementation, in the embodiments of this application, the oxygen source includes one or a combination of water or ozone.
[0014] As an optional implementation, in the embodiments of this application, the substrate includes one or more combinations of silicon substrate, glass, transparent conductive material, electron transport material or perovskite material.
[0015] Secondly, embodiments of this application provide a tin oxide film.
[0016] The tin oxide film is prepared by the preparation method mentioned in the first aspect.
[0017] As an optional implementation, in the embodiments of this application, the non-uniformity of the tin oxide film is less than 4.2%; the average film thickness is 10nm to 30nm.
[0018] Thirdly, embodiments of this application provide a solar cell.
[0019] The solar cell includes the tin oxide film prepared by the method described in the first aspect, or the tin oxide film described in the second aspect.
[0020] As an optional implementation, in the embodiments of this application, the solar cell is a perovskite tandem solar cell, which includes a bottom cell and a top cell. The top cell includes a hole transport layer, a perovskite layer, an electron transport layer, the tin oxide film, and a transparent conductive layer stacked sequentially from bottom to top.
[0021] As an optional implementation, in the embodiments of this application, the solar cell is a single-junction perovskite solar cell, which includes a transparent conductive substrate, a hole transport layer, a perovskite layer, an electron transport layer, the tin oxide film, and the transparent conductive layer stacked sequentially from bottom to top.
[0022] Fourthly, embodiments of this application provide a photovoltaic module.
[0023] A photovoltaic module comprising a solar cell as described in the third aspect.
[0024] Compared with the prior art, the beneficial effects of this application are as follows:
[0025] This application provides a method for preparing a tin oxide film. In the tin source of this application, the hydrogen atoms bonded to the N atoms can form hydrogen bonds with water molecules, exhibiting strong hydrophilicity. Furthermore, the steric hindrance of the tin source is small, making it very easy for the tin source to combine with the oxygen source. During the preparation of the tin oxide film, the tin source and oxygen source more easily and uniformly adsorb and react with each other, thereby effectively reducing atomic defects in the tin oxide film and improving the uniformity of the film thickness. Attached Figure Description
[0026] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0027] Figure 1 This is a schematic diagram of one cycle of the tin oxide film preparation process disclosed in the embodiments of this application;
[0028] Figure 2 This is a schematic diagram of the structure of the solar cell disclosed in the embodiments of this application.
[0029] Icons: 10. N-type single crystal silicon; 11. First intrinsic layer; 12. Second intrinsic layer; 13. P-type doped layer; 14. N-type doped layer; 15. First transparent conductive layer; 16. Composite layer; 17. First electrode; 21. Hole transport layer; 22. Perovskite layer; 23. Passivation layer; 24. Electron transport layer; 25. Tin oxide film; 26. Second transparent conductive layer; 27. Antireflection layer; 28. Second electrode. Detailed Implementation
[0030] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0031] In this application, the terms "upper," "lower," "left," "right," "front," "rear," "top," "bottom," "inner," "outer," "middle," "vertical," "horizontal," "lateral," and "longitudinal" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are primarily for the purpose of better describing this application and its embodiments, and are not intended to limit the indicated device, element, or component to having a specific orientation, or to be constructed and operated in a specific orientation.
[0032] Furthermore, in addition to indicating location or positional relationship, some of the aforementioned terms may also have other meanings. For example, the term "above" may also be used in some cases to indicate a certain dependency or connection relationship. Those skilled in the art can understand the specific meaning of these terms in this application based on the specific circumstances.
[0033] Furthermore, the terms "installation," "setup," "equipped with," "connection," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral structure; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium, or an internal connection between two devices, components, or parts. Those skilled in the art can understand the specific meaning of these terms in this application based on the specific circumstances.
[0034] Furthermore, the terms "first," "second," etc., are primarily used to distinguish different devices, elements, or components (which may be the same or different in specific type and construction), and are not intended to indicate or imply the relative importance or quantity of the indicated devices, elements, or components. Unless otherwise stated, "a plurality of" means two or more.
[0035] Atomic layer deposition (ALD) primarily involves alternating pulses of a gaseous precursor into a reaction chamber, causing the precursor to undergo a chemical adsorption reaction on the substrate surface. This process deposits the precursor layer by layer as a single-atom film, forming a thin film. In the preparation of tin oxide thin films, current tin sources, such as tetra(dimethylamino)tin, have poor hydrophilicity, making it difficult for the tin source to chemically react with the oxygen source. Therefore, the tin source cannot achieve a good adsorption effect on the oxygen source surface, resulting in tin oxide films with poor uniformity.
[0036] To improve the uniformity of tin oxide film, this application provides a method for preparing tin oxide film, tin oxide film, solar cell, and photovoltaic module.
[0037] The technical solution of this application will be further described below with reference to the embodiments and accompanying drawings.
[0038] In a first aspect, embodiments of this application provide a method for preparing a tin oxide film.
[0039] A method for preparing a tin oxide film, comprising:
[0040] The tin oxide film is deposited on the substrate surface using atomic layer deposition (ALD) with a tin source and an oxygen source acting on the reactants. The tin source includes a compound of formula I:
[0041] In Equation I, n = 1, 2, 3, 4.
[0042] The hydrogen atoms bonded to the N atom in the aforementioned tin source can form hydrogen bonds with water molecules, exhibiting strong hydrophilicity. Furthermore, the steric hindrance of this tin source is small, making it very easy for it to combine with the oxygen source. During the preparation of tin oxide films, the tin and oxygen sources more readily and uniformly adsorb and react with each other, effectively reducing atomic defects in the tin oxide film and improving its thickness uniformity.
[0043] Specifically, C n H 2n+1 The alkyl group can be either a straight-chain alkyl group or a branched alkyl group. For example, the straight-chain alkyl group can be methyl, ethyl, n-propyl, or n-butyl, and the branched alkyl group can be isopropyl. Shorter carbon chains are more advantageous for the reaction of the compound of Formula I with an oxygen source to prepare tin oxide, resulting in a higher uniformity of tin oxide film thickness. If the carbon chain is too short or a more sterically hindered group (such as benzyl or a long-chain alkyl group with n greater than 4) is introduced, the reaction to prepare the tin oxide layer becomes more difficult, leading to a significant decrease in the uniformity of the tin oxide film thickness.
[0044] It should be noted that, referring to Figure 1 The deposition order of tin source and oxygen source can be interchanged. When the precursor of source 1 is tin source and the precursor of source 2 is oxygen source, or when the precursor of source 1 is oxygen source and the precursor of source 2 is tin source.
[0045] In some embodiments, the compound of formula I is selected from at least one of the following compounds:
[0046]
[0047] In some embodiments, the preparation method of the compound of formula I includes the following steps:
[0048] In the presence of an organolithium catalyst, an alkyl primary amine and tin tetrachloride are refluxed in a solvent to give the compound of formula I as mentioned in the first aspect.
[0049] The synthetic route for compound I is as follows:
[0050]
[0051] Organolithium compounds are used as catalysts for the synthesis of Formula I compounds. Under the catalysis of organolithium catalysts, the reactivity of alkyl primary amines with tin tetrachloride is enhanced, yielding Formula I compounds with the above-mentioned structure. This reaction process is simple, the raw materials are readily available, and the yield is high and the production is stable, which is conducive to industrial production and promotion.
[0052] In some embodiments, the reaction is carried out in an inert gas environment.
[0053] In an inert environment, the reaction stability of alkyl primary amines with tin tetrachloride is improved, side reactions are reduced, the yield of Formula I compounds is increased, and more impurity components are avoided.
[0054] In some embodiments, the reaction temperature for preparing compound I is -10°C to 0°C; and / or, the reaction time for preparing compound I is 3h to 6h.
[0055] At excessively low temperatures or for excessively short reaction times, the reaction is incomplete; at excessively high temperatures or for excessively long reaction times, it is prone to over-reaction, causing the secondary amine structure in Formula I compound to further transform into a tertiary amine structure. This results in increased steric hindrance of Formula I compound, which is detrimental to the chemical reaction between Formula I compound and oxygen source, and is not conducive to further improving the uniformity of tin oxide film thickness. Therefore, within the above-mentioned reaction temperature and reaction time range, the yield of the Formula I compound with the specific structure is at a relatively high level.
[0056] For example, the reaction temperature can be -10℃, -9℃, -8℃, -7℃, -6℃, -5℃, -4℃, -3℃, -2℃, -1℃ and 0℃, etc., and the reaction time can be 3h, 4h, 5h and 6h, etc.
[0057] In some embodiments, the alkyl primary amine includes one of methylamine, ethylamine, propylamine, isopropylamine, or butylamine; and / or, the organolithium catalyst includes one or more combinations of methyllithium, n-butyllithium, and phenyllithium; and / or, the solvent includes one or more combinations of anhydrous diethyl ether, tetrahydrofuran, anhydrous toluene, and hexane.
[0058] Methylamine, ethylamine, propylamine, isopropylamine, or butylamine, as alkyl primary amines, react with tin tetrachloride to prepare Formula I compounds with secondary amine structures. Formula I compounds with this structure have less steric hindrance and better hydrophilicity, and can react rapidly with oxygen sources, which is beneficial for preparing high-quality tin oxide films and reducing defects in tin oxide films.
[0059] Methyllithium, n-butyllithium, and phenyllithium are good organic lithium catalysts with excellent catalytic effects and the advantage of readily available raw materials.
[0060] Solvents include one or more combinations of anhydrous diethyl ether, tetrahydrofuran, anhydrous toluene, and hexane. These solvents are commercially available reagents and require no special treatment. Anhydrous diethyl ether, tetrahydrofuran, anhydrous toluene, and hexane exhibit good solubility for alkyl primary amines, tin tetrachloride, and organolithium compounds, promoting the reaction to proceed in a homogeneous system.
[0061] In some embodiments, the molar ratio of tin tetrachloride to alkyl primary amine is 1:4 to 6, and the molar ratio of tin tetrachloride to n-butyllithium is 1:4.4 to 5.
[0062] By controlling the molar ratio of tin tetrachloride to alkyl primary amine, the reaction is favored to generate compound I with a secondary amine structure. When the molar ratio of tin tetrachloride to alkyl primary amine is too small, the reaction of tin tetrachloride and alkyl primary amine is more likely to generate byproducts with a tertiary amine structure.
[0063] For example, the molar ratio of tin tetrachloride to alkyl primary amine can be 1:4, 1:4.5, 1:5, 1:5.5 and 1:6, etc., and the molar ratio of tin tetrachloride to n-butyllithium can be 1:4.4, 1:4.8, 1:5, 1:5.5 and 1:5, etc.
[0064] In some embodiments, the solvent is a combination of anhydrous diethyl ether, tetrahydrofuran, anhydrous toluene, and hexane, and the mixing order of the organolithium catalyst, alkyl primary amine, and tin tetrachloride is as follows:
[0065] Dissolution: First, the organolithium catalyst was dissolved in hexane to obtain a hexane solution of the organolithium catalyst; then, the alkyl primary amine was dissolved in tetrahydrofuran to obtain a tetrahydrofuran solution of the alkyl primary amine.
[0066] Mixing: Dissolve the hexane solution of the organolithium catalyst in anhydrous diethyl ether to obtain the first solution. After purging the air with an inert gas, add the tetrahydrofuran solution of the alkyl primary amine dropwise to the mixture and stir to obtain the second solution. Dissolve tin tetrachloride in anhydrous toluene to obtain an anhydrous toluene solution of tin tetrachloride. Add the anhydrous toluene solution of tin tetrachloride dropwise to the second solution to carry out the reaction.
[0067] Mixing in the above order promotes the formation of more Formula I compounds, reduces the formation of byproducts and impurities, and improves product purity. Furthermore, mixing the components dropwise helps the reaction proceed gently, effectively suppressing excessive exothermic reactions caused by rapid addition, thus reducing the probability of side reactions and minimizing safety risks.
[0068] In some embodiments, the concentration of the hexane solution of the organolithium catalyst is 2 mol / L to 4 mol / L; and / or, the concentration of the tetrahydrofuran solution of the alkyl primary amine is 1.5 mol / L to 3 mol / L, and the concentration of the anhydrous toluene solution of tin tetrachloride is 0.45 mol / L to 0.6 mol / L.
[0069] For example, the concentration of the hexane solution of the organolithium catalyst can be 2 mol / L, 2.5 mol / L, 3 mol / L, 3.5 mol / L, and 4 mol / L, etc. The concentration of the tetrahydrofuran solution of the alkyl primary amine can be 1.5 mol / L, 1.8 mol / L, 2.1 mol / L, 2.5 mol / L, 2.8 mol / L, and 3 mol / L, etc. The concentration of the anhydrous toluene solution of tin tetrachloride can be 0.45 mol / L, 0.48 mol / L, 0.5 mol / L, 0.54 mol / L, 0.56 mol / L, 0.58 mol / L, and 0.6 mol / L, etc.
[0070] In some embodiments, after the reaction is complete, the solvent is removed and the mixture is purified by distillation to obtain the compound of formula I.
[0071] The solvent can be removed by rotary evaporation under reduced pressure, followed by purification by distillation under reduced pressure to obtain the compound of formula I.
[0072] In some embodiments, the dose-time ratio of tin source to oxygen source is 1 to 100:1.
[0073] It should be noted that the dose-time is the length of time during which the gas-phase precursor is pulsed into the reaction chamber.
[0074] In the preparation of the tin oxide film, source 1 precursor is first introduced and held for time t1, followed by purging for time Δt1. Then, source 2 precursor is introduced and held for time t2, followed by purging for time Δt2, completing one cycle. Exemplarily, when source 1 precursor is a tin source and source 2 precursor is an oxygen source, the dose-time ratio of the tin source to the oxygen source is the ratio of t1 to t2. Exemplarily, t1 ranges from 0.1 s to 1.2 s, Δt1 ranges from 1 s to 20 s, t2 ranges from 0.01 s to 0.1 s, and Δt2 ranges from 1 s to 20 s. When source 1 precursor is an oxygen source and source 2 precursor is a tin source, the dose-time ratio of the tin source to the oxygen source is the ratio of t2 to t1. For example, t1 takes the value of 0.01s to 0.1s, Δt1 takes the value of 1s to 20s, t2 takes the value of 0.1s to 1.2s, and Δt2 takes the value of 1s to 20s. Then the ratio of t1 to t2 is the dose-time ratio of the tin source to the oxygen source.
[0075] In some embodiments, the oxygen source includes one or a combination of water or ozone.
[0076] Both water and ozone are highly chemically reactive and can react with tin sources to provide oxygen atoms for the formation of tin oxide. This application uses water and ozone as oxygen sources, enabling the formation of a stable oxide layer on the substrate surface, thus meeting the requirements for self-limited growth in atomic layer deposition.
[0077] In some embodiments, the substrate includes one or more combinations of silicon substrate, glass, transparent conductive material, electron transport material, or perovskite material.
[0078] The tin oxide film has a wide range of substrate options, including silicon, glass, and transparent conductive materials. Furthermore, when applied to perovskite tandem solar cells, the tin oxide film can be based on either electron transport materials or perovskite materials.
[0079] Secondly, embodiments of this application provide a tin oxide film.
[0080] The tin oxide film was prepared by the preparation method mentioned in the first aspect.
[0081] In some embodiments, the non-uniformity of the tin oxide film is less than 4.2%; the average film thickness is 10 nm to 30 nm.
[0082] For example, the non-uniformity of the tin oxide film can be 1%, 1.2%, 1.4%, 1.6%, 1.8%, 2%, 2.3%, 2.6%, 2.8%, 3%, 3.4%, 3.7%, 4%, and 4.2%, etc. The average film thickness can be 10nm, 12nm, 14nm, 16nm, 18nm, 20nm, 23nm, 26nm, 28nm, and 30nm, etc.
[0083] Thirdly, embodiments of this application provide a solar cell.
[0084] Reference Figure 2 A solar cell comprising a tin oxide film 25 as mentioned in the first aspect, or a tin oxide film 25 as mentioned in the second aspect.
[0085] In some embodiments, the solar cell is a perovskite tandem solar cell, which includes a bottom cell and a top cell. The top cell includes a hole transport layer 21, a perovskite layer 22, an electron transport layer 24, a tin oxide film 25, and a second transparent conductive layer 26 stacked sequentially from bottom to top.
[0086] The aforementioned tin oxide film 25 has better film thickness uniformity, which can better cover the perovskite and play a buffering role, which is beneficial to improving the fill factor and open circuit voltage of the solar cell and improving the energy conversion efficiency of the solar cell.
[0087] In some embodiments, the method for fabricating the bottom battery includes the following steps:
[0088] N-type monocrystalline silicon 10 pretreatment: Take N-type monocrystalline silicon 10 and perform double-sided chemical polishing to remove oil stains and cutting damage layers from the surface of monocrystalline silicon, forming a pyramid light trapping structure;
[0089] Intrinsic layer deposition: A first intrinsic layer 11 with a thickness of 5 nm to 10 nm is deposited on the first side of the N-type single crystal silicon 10 using chemical vapor deposition, and a second intrinsic layer 12 with a thickness of 5 nm to 10 nm is deposited on the second side opposite to the first side.
[0090] N-type doped layer 14 deposition: An N-type doped layer 14 with a thickness of 5 nm to 20 nm is deposited on the second intrinsic layer 12 using chemical vapor deposition. The doping element can be phosphorus.
[0091] P-type doped layer 13 deposition: A P-type doped layer 13 with a thickness of 5 nm to 30 nm is deposited on the first intrinsic layer 11 using chemical vapor deposition. The doping element can be boron.
[0092] First transparent conductive layer 15 deposition: A first transparent conductive film layer with a thickness of 70nm to 100nm is deposited on the P-type doped layer 13 using physical vapor deposition. The material is a TCO transparent conductive material, specifically ITO (indium tin oxide), IWO (indium tungsten oxide), ICO (indium cesium oxide), IZO (indium zinc oxide), AZO (zinc oxide), and FTO (indium fluorine oxide).
[0093] Composite layer 16 deposition: A composite layer 16 with a thickness of 1 nm to 80 nm is deposited on the N-type doped layer 14 using physical vapor deposition. The material is a TCO transparent conductive material, specifically ITO (indium tin oxide), IWO (indium tungsten oxide), ICO (indium cesium oxide), IZO (indium zinc oxide), AZO (zinc oxide), and FTO (indium fluorine oxide).
[0094] Preparation of the first electrode 17: The first electrode 17 is prepared on the first transparent conductive layer 15 by vapor deposition, and the material is silver.
[0095] In some embodiments, the fabrication method of the top cell includes the following steps:
[0096] Hole transport layer 21 deposition: Hole transport layer 21 is deposited on composite layer 16 using physical vapor deposition. The thickness is 10nm~30nm, and the material is an inorganic hole transport material, specifically Spriro-OMETAD, NiCo2O4, CuS, V2O5, NiLiMgO, CuSCN, MoO3, CuGaO2, SrCO3, CuI, NiO X The hole transport layer 21 can be one or more of the following: CuO, Cu2O, CuCrO2 or CuScO2, or it can be a self-assembled monolayer. The hole transport layer 21 can be a single layer formed by inorganic hole transport material or self-assembled material, or it can be a double layer formed by inorganic hole transport material and self-assembled material together.
[0097] Perovskite layer 22 deposition: The perovskite precursor solution was coated onto the surface of hole transport layer 21 using a solution method and then annealed to obtain a perovskite layer 22 with a thickness of 0.3 μm to 1 μm.
[0098] Electron transport layer 24 deposition: Electron transport layer 24 is prepared on the surface of perovskite layer 22 by vapor deposition, with a thickness of 10 nm to 30 nm. The material can be fullerene and its derivatives.
[0099] Tin oxide film 25 deposition: A tin oxide film 25 is deposited on the electron transport layer 24 using atomic layer deposition (ALD). The process temperature is controlled at 50°C to 100°C. Using the tin oxide film 25 preparation method mentioned in the first aspect, tin and oxygen sources are alternately introduced into the reaction chamber in a pulsed manner to complete the deposition of the tin oxide film. Exemplarily, the tin source is used as source 1 precursor, held for time t1, then purged for time Δt1. Then, an oxygen source is introduced as source 2 precursor, held for time t2, and then purged for time Δt2, completing one cycle. This cycle is repeated 100 to 150 times to obtain a tin oxide film 25 with a thickness of 10 nm to 30 nm. Preferably, t1 is 0.1 s to 1.2 s, Δt1 is 1 s to 20 s, t2 is 0.01 s to 0.1 s, and Δt2 is 1 s to 20 s.
[0100] Deposition of the second transparent conductive layer 26: The second transparent conductive layer 26 is prepared by physical vapor deposition, with a thickness of 40nm to 100nm. The material is a TCO transparent conductive material, which can be ITO (indium tin oxide), IWO (indium tungsten oxide), ICO (indium cesium oxide), IZO (indium zinc oxide), AZO (zinc oxide), and FTO (indium fluorine oxide).
[0101] Preparation of the second electrode 28: A metal electrode is prepared on the second transparent conductive layer 26 by vapor deposition, and the material is silver.
[0102] In some embodiments, the solar cell is a single-junction perovskite solar cell, which includes a transparent conductive substrate, a hole transport layer 21, a perovskite layer 22, an electron transport layer 24, a tin oxide film 25, and a transparent conductive layer stacked sequentially from bottom to top.
[0103] Fourthly, embodiments of this application provide a photovoltaic module.
[0104] A photovoltaic module, comprising solar cells as mentioned in the third aspect.
[0105] The technical solution of this application will be further described below with reference to the embodiments and accompanying drawings.
[0106] Preparation Example 1
[0107] This application provides a method for preparing a compound of formula I, comprising the following steps:
[0108] Dissolution: First, dissolve n-butyllithium in hexane to obtain a first solution with a concentration of 2.5 mol / L; then dissolve ethylamine in tetrahydrofuran to obtain a second solution with a concentration of 2 mol / L.
[0109] Mixing: Dissolve 500 mL of the first solution in 500 mL of anhydrous diethyl ether to obtain a mixture. After purging the air with argon gas, cool the mixture to 0 °C. Add 568 mL of the second solution dropwise to the mixture. After the addition is complete, stir at 0 °C for 1 h. Dissolve 74 g of tin tetrachloride in 500 mL of anhydrous toluene to obtain a third solution. Add the third solution dropwise to the mixture and reflux the reaction system for 4 h. After the reaction is complete, cool the reaction system to room temperature and remove the solvent by evaporation under reduced pressure to obtain the target compound. The yield is 53.79 g, and the yield is 64.2%.
[0110] Preparation Example 2
[0111] This application provides a method for preparing a compound of formula I, which differs from Example 1 in that methylamine is used instead of ethylamine, while the rest remains the same as in Example 1. The yield of the target compound is 41.24 g, with a yield of 60.5%.
[0112] Preparation Example 3
[0113] This application provides a method for preparing a compound of formula I, which differs from Example 1 in that propylamine is used instead of ethylamine; otherwise, the method remains the same as in Example 1. The yield of the target compound is 61.30 g, with a yield of 61.3%.
[0114] Preparation Example 4
[0115] This application provides a method for preparing a compound of formula I, which differs from Example 1 in that isopropylamine is used instead of ethylamine, while the rest remains the same as in Example 1. The yield of the target compound is 67.60 g, with a yield of 67.6%.
[0116] Preparation Example 5
[0117] This application provides a method for preparing a compound of formula I, which differs from Example 1 in that n-butylamine is used instead of ethylamine; otherwise, the method remains the same as in Example 1. The yield of the target compound is 71.53 g, with a yield of 61.7%.
[0118] Example 1
[0119] A solar cell includes a bottom cell and a top cell. The bottom cell, from bottom to top, consists of a first electrode, a first transparent conductive layer, a P-type doped layer, a first intrinsic layer, an N-type monocrystalline silicon layer, a second intrinsic layer, an N-type doped layer, and a composite layer. The top cell, from bottom to top, consists of a hole transport layer, a perovskite layer, a passivation layer, an electron transport layer, a buffer layer, a second transparent conductive layer, a second electrode, an antireflection layer, and a second electrode. The hole transport layer is stacked on top of the composite layer.
[0120] The above-mentioned method for preparing solar cells includes the following steps:
[0121] N-type monocrystalline silicon pretreatment: Take N-type monocrystalline silicon and perform double-sided chemical polishing to remove oil stains and cutting damage layers from the surface of the monocrystalline silicon, forming a crystalline pyramid light-trapping structure;
[0122] Intrinsic layer deposition: A first intrinsic layer with a thickness of 7 nm was deposited on the first side of the N-type single crystal silicon using chemical vapor deposition, and a second intrinsic layer with a thickness of 7 nm was deposited on the second side opposite to the first side.
[0123] N-type doped layer deposition: An N-type doped layer with phosphorus as the doping element was deposited on the second intrinsic layer by chemical vapor deposition, and the thickness was 15 nm.
[0124] P-type doped layer deposition: A P-type doped layer with boron as the dopant element and a thickness of 15 nm was deposited on the first intrinsic layer using chemical vapor deposition.
[0125] First transparent conductive layer deposition: A first transparent conductive film layer with a thickness of 80 nm was deposited on the P-type doped layer using physical vapor deposition. The material was ITO.
[0126] TCO composite layer deposition: A TCO composite layer with a thickness of 20 nm was deposited on the N-type doped layer using physical vapor deposition. The material was ITO.
[0127] Hole transport layer deposition: A hole transport layer with a thickness of 20 nm was deposited on the composite layer using physical vapor deposition. The material was Spriro-OMETAD.
[0128] Perovskite layer deposition: The perovskite precursor solution was coated onto the surface of the hole transport layer using a solution method, followed by annealing to obtain a perovskite layer with a thickness of 0.5 μm.
[0129] Electron transport layer deposition: An electron transport layer with a thickness of 20 nm was prepared on the surface of the perovskite layer by vapor deposition. The material was fullerene and its derivatives.
[0130] Tin oxide film deposition: Atomic layer deposition method is used to deposit tin oxide film on electron transport layer. The process temperature is controlled at 75℃. Tin source and water are alternately introduced into reaction chamber by pulse. Tin source is introduced for 10s, purged for 10s, then H2O gas is introduced for 10s, purged for 10s, and this completes one growth cycle. The growth cycle is repeated 120 times to obtain tin oxide film with a thickness of 20nm.
[0131] Second transparent conductive layer deposition: The second transparent conductive layer was prepared by physical vapor deposition, with a thickness of 60 nm, and the material was ITO;
[0132] Preparation of the first electrode: A metal electrode with a thickness of 1 μm and made of silver was prepared on the first transparent conductive layer by vapor deposition.
[0133] Preparation of the second electrode: A metal electrode with a thickness of 1 μm and made of silver was prepared on the second transparent conductive layer by vapor deposition.
[0134] In this case, the tin source for preparing the tin oxide film is the compound from Preparation Example 1.
[0135] Example 2
[0136] This application provides a solar cell, which differs from Example 1 in that the tin source for preparing the tin oxide film is the compound of Formula I in Example 2, while the rest remains the same as in Example 1.
[0137] Example 3
[0138] This application provides a solar cell, which differs from Example 1 in that the tin source for preparing the tin oxide film is the compound of Formula I in Example 3, while the rest is the same as in Example 1.
[0139] Example 4
[0140] This application provides a solar cell, which differs from Example 1 in that the tin source for preparing the tin oxide film is the compound of Formula I in Example 4, while the rest remains the same as in Example 1.
[0141] Example 5
[0142] This application provides a solar cell, which differs from Example 1 in that the tin source for preparing the tin oxide film is the compound of Formula I in Example 5, while the rest is the same as in Example 1.
[0143] Comparative Example 1
[0144] This application provides a comparative example of a solar cell, which differs from Example 1 in that the tin source for preparing the tin oxide film is tetrakis(dimethylamino)tin, while the rest remains the same as in Example 1.
[0145] Experiment 1
[0146] Tin oxide film thickness uniformity test
[0147] The testing areas are: the area directly below the tin source inlet (hereinafter referred to as the inlet), the middle area close to the tin source inlet (hereinafter referred to as the upper middle), the middle area close to the tin source outlet (hereinafter referred to as the lower middle), and the area directly below the tin source outlet (hereinafter referred to as the outlet).
[0148] Two solar cells are placed in each region, and these solar cells are prepared according to the method described in Example 1. After the electron transport layer is prepared, it is placed with the electron transport layer exposed upwards, and a tin oxide layer is deposited. The thickness of the tin oxide layer before and after deposition is measured, and the thickness difference before and after deposition is calculated to obtain the thickness of the tin oxide film.
[0149] Further calculations were performed on the mean thickness and thickness non-uniformity of the tin oxide film. The mean thickness was calculated as follows: ∑X n / n, the method for calculating film thickness non-uniformity is: (X max -X min ) / (X max +X min ), X max X represents the maximum value in the tin oxide film thickness test results. min This represents the minimum value in the tin oxide film thickness test results.
[0150] The test results of Experiment 1 are shown in Table 1.
[0151] Table 1
[0152]
[0153]
[0154] A comparison of the thickness uniformity test results of the tin oxide films in Examples 1, 2, 5, and Comparative Example 1 in Table 1 shows that: the tin oxide film thickness non-uniformity in Example 2 is the lowest, at 1.5%; the tin oxide film thickness non-uniformity in Example 1 is close to that in Example 2, at 1.7%; the tin oxide film thickness non-uniformity in Example 5 is lower than that in Examples 1 and 2, at 4.2%; and the tin oxide film thickness non-uniformity in Comparative Example 1 is 5.2%, indicating that the non-uniformity of the tin oxide film in Example 5 is still significantly lower than that in Comparative Example 1. It is evident that the uniformity of the tin oxide films prepared in the above examples is higher than that in Comparative Example 1, proving that using the compound of Formula I as the tin source has a significant effect on improving the uniformity of the tin oxide film. Furthermore, a comparison of the tests in Examples 1, 2, and 5 shows that the shorter the carbon chain length in the compound of Formula I, the more favorable it is for the tin oxide preparation reaction, and the lower the thickness non-uniformity of the tin oxide film.
[0155] Experiment 2
[0156] Solar cell performance testing
[0157] In the solar cell fabrication process of each embodiment and comparative example, two solar cells were placed in each of the four regions defined in Experiment 1 to prepare the tin oxide film layer, while the rest remained unchanged. After the solar cells were fabricated, the performance of the solar cells was tested using the Wavelabs solar simulator under the following conditions: AM1.5, 1000 W / m². 2 The test environment temperature was 25℃. Before testing, the sunlight intensity was calibrated using a standard silicon solar cell to simulate the light source. The open-circuit voltage, short-circuit current, fill factor, and power conversion efficiency (PCE) of the corresponding solar cells were recorded. The mean and standard deviation of the open-circuit voltage (Voc), short-circuit current (Jsc), fill factor (FF), and PCE for each embodiment and comparative example solar cell were calculated.
[0158] The test results of Experiment 2 are shown in Tables 2 and 3.
[0159] Table 2
[0160]
[0161] Table 3
[0162] Voc standard deviation Jsc standard deviation FF standard deviation PCE standard deviation Example 1 0.121 0.611 7.2 3.5 Example 2 0.115 0.599 7.5 3.2 Example 3 0.166 0.723 8.1 4.3 Example 4 0.173 0.731 7.9 4.5 Example 5 0.192 0.811 8.8 4.9 Comparative Example 1 0.212 0.815 8.9 5.1
[0163] A comparison of the test results of Examples 1, 2, 3, 4, 5 and Comparative Example 1 in Tables 2 and 3 shows that the average Voc, average FF, and average PCE values of the above examples are all higher than those of Comparative Example 1. Specifically, the average Voc value of Example 2 is 0.086V higher than that of Comparative Example 1, the average FF value is 8.95% higher, and the average PCE value is 3.66% higher. This demonstrates that using the compound of Formula I provided in this application as the tin source results in a tin oxide film with low thickness non-uniformity, which is beneficial for improving the Voc, FF, and PCE of solar cells. Furthermore, the standard deviations of Voc, FF, and PCE in the above examples are all lower than those in Comparative Example 1, proving that using the compound of Formula I provided in this application as the tin source results in a tin oxide film with low thickness non-uniformity. This is beneficial for improving the stability of solar cells and the reliability of test results, and avoiding excessive performance differences between different batches of solar cells.
[0164] The preparation method of tin oxide film, tin oxide film, solar cell, and photovoltaic module disclosed in the embodiments of this application have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. The description of the above embodiments is only for the purpose of helping to understand the preparation method of tin oxide film, tin oxide film, solar cell, photovoltaic module and its core ideas of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.
Claims
1. A method for preparing a tin oxide film, characterized in that, include: The tin oxide film is deposited on the substrate surface using atomic layer deposition (ALD) with a tin source and an oxygen source acting on the reactants. The tin source includes a compound of formula I: In the compound of Formula I, n = any one of 1, 2, 3 or 4.
2. The method for preparing the tin oxide film according to claim 1, characterized in that, The compound of formula I is selected from at least one of the following compounds:
3. The method for preparing the tin oxide film according to claim 1, characterized in that, The preparation method of the compound of formula I is as follows: alkyl primary amine and tin tetrachloride are refluxed in a solvent in the presence of an organolithium catalyst to obtain the compound of formula I.
4. The method for preparing the tin oxide film according to claim 3, characterized in that, The alkyl primary amine includes one of methylamine, ethylamine, propylamine, isopropylamine, or butylamine; and / or, the organolithium catalyst includes one or more combinations of methyllithium, n-butyllithium, and phenyllithium; and / or, the solvent includes one or more combinations of anhydrous diethyl ether, tetrahydrofuran, anhydrous toluene, and hexane.
5. The method for preparing a tin oxide film according to claim 1 or 2, characterized in that, The dose-time ratio of the tin source to the oxygen source is 1 to 100:
1.
6. The method for preparing a tin oxide film according to claim 1 or 2, characterized in that, The oxygen source includes one or a combination of water and ozone.
7. The method for preparing a tin oxide film according to claim 1 or 2, characterized in that, The substrate includes one or more combinations of silicon substrate, glass, transparent conductive material, electron transport material or perovskite material.
8. A tin oxide film, characterized in that: The tin oxide film is prepared by the method described in any one of claims 1 to 7.
9. The tin oxide film according to claim 8, characterized in that, The non-uniformity of the tin oxide film is less than 2%, and the average film thickness is 10 nm to 30 nm.
10. A solar cell, characterized in that: The tin oxide film prepared by the method of any one of claims 1 to 7, or the tin oxide film according to any one of claims 8 to 9.
11. The solar cell according to claim 10, characterized in that, The solar cell is a perovskite tandem solar cell, which includes a bottom cell and a top cell. The top cell includes a hole transport layer, a perovskite layer, an electron transport layer, the tin oxide film, and a transparent conductive layer stacked sequentially from bottom to top.
12. The solar cell according to claim 10, characterized in that, The solar cell is a single-junction perovskite solar cell, which includes, from bottom to top, a transparent conductive substrate, a hole transport layer, a perovskite layer, an electron transport layer, the tin oxide film, and the transparent conductive layer stacked in sequence.
13. A photovoltaic module, characterized in that, Including the solar cells as described in claims 10-12.