A perovskite solar cell and its fabrication method

Abstract

This invention relates to the field of solar photovoltaic technology, specifically to a perovskite solar cell and its fabrication method. In the fabrication method of the perovskite solar cell, an electron transport layer is formed using ion-assisted deposition technology; wherein the angle formed between the direction from the center of the target material to the center of the substrate and the emission direction of the ion beam is greater than or equal to 90° and less than 180°, the target material is at least one of a sulfide or a selenide, and the conduction band bottom of the target material is lower than the conduction band bottom of the perovskite layer. The above-mentioned fabrication method of the perovskite solar cell easily ensures both processing efficiency and cell performance.

Description

Technical Field

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

[0002] Perovskite is a highly attractive semiconductor material, possessing excellent properties such as high absorption coefficient, low exciton binding energy, tunable band structure, and long carrier diffusion length. As a novel type of thin-film solar cell, perovskite solar cells have rapidly achieved efficiencies exceeding 22%, demonstrating their potential and promising future. The structure of a perovskite solar cell includes: a substrate, a transparent conductive layer, a hole transport layer, a perovskite layer, an electron transport layer, and metal electrodes.

[0003] However, most electron transport layers are currently prepared using solution methods, which involve complex processing routes and make it difficult to balance processing efficiency and battery performance, thus hindering the industrial production of perovskite solar cells. Summary of the Invention

[0004] Therefore, in order to solve the above-mentioned technical problems, the present invention provides a perovskite solar cell and a method for preparing the same.

[0005] This invention provides a method for fabricating a perovskite solar cell, which uses ion-assisted deposition technology to form an electron transport layer; wherein the angle formed between the direction from the center of the target material to the center of the substrate and the emission direction of the ion beam is greater than or equal to 90° and less than 180°, the target material is at least one of sulfide or selenide, and the conduction band bottom of the target material is lower than the conduction band bottom of the perovskite layer.

[0006] Optionally, the direction from the center of the target to the center of the substrate is perpendicular to the emission direction of the ion beam.

[0007] Optionally, the deposition rate of the electron transport layer is

[0008] Optionally, the thickness of the electron transport layer is 2nm-25nm.

[0009] Optionally, during the deposition of the electron transport layer, the flow rate of the working gas introduced into the ion source is 10 sccm-100 sccm; the operating voltage of the ion source is 100V-2000V; and the operating current of the ion source is 0.1A-2A.

[0010] Optionally, the working gas is an inert gas.

[0011] Optionally, the process for forming a gaseous deposit from the target material includes magnetron sputtering, thermal evaporation deposition, and electron beam evaporation.

[0012] Optionally, the process parameters for forming the gaseous material to be deposited using thermal evaporation deposition include: the current of the target material is 0.1A-10A, and the voltage of the target material is 200V-300V.

[0013] Optionally, during the deposition of the electron transport layer, the atmosphere in the deposition chamber is an inert atmosphere.

[0014] Optionally, the perovskite solar cell is an inverted perovskite solar cell.

[0015] Optionally, the sulfides include Bi2S3, In2S3, TiS2, and SnS2; the selenides include CdSe, ZnSe, and In2Se3.

[0016] The present invention also provides a perovskite solar cell, including an electron transport layer, wherein the electron transport layer is made of an N-type sulfide or selenide.

[0017] Optionally, the perovskite solar cell is an inverted perovskite solar cell.

[0018] The technical solution of this invention has the following advantages:

[0019] 1. The method for fabricating a perovskite solar cell provided by this invention employs ion-assisted deposition technology to form an electron transport layer. The target material is at least one of sulfide or selenide. By limiting the angle between the direction from the center of the target material to the center of the substrate and the emission direction of the ion beam to be greater than or equal to 90° and less than 180°, the gaseous material to be deposited from the target material is bombarded by the ion beam during its movement towards the substrate, thereby losing some energy. This avoids damage to the functional layer below the electron transport layer, especially the organic functional layer, due to the high energy of the material to be deposited, thus ensuring the efficiency of the perovskite solar cell. Simultaneously, it also makes the cations and anions in the gaseous material to be deposited more reactive, thus separating them. Compared to cations, sulfide ions... Selenium ions are more easily lost, leading to the recombination of anions and cations and the absence of sulfide or selenium ions. This results in the electron transport layer being an N-type sulfide or selenide, which improves the electron mobility of the electron transport layer and thus enhances the efficiency of perovskite solar cells. Furthermore, the use of inorganic materials for the electron transport layer not only reduces cost but also effectively blocks moisture from the environment, improving the stability and extending the lifespan of perovskite solar cells. In addition, the electron transport layer is formed using ion-assisted deposition technology, a simple preparation method suitable for large-scale commercial production. In summary, the perovskite solar cell preparation method provided by this invention easily balances processing efficiency with battery performance.

[0020] 2. The perovskite solar cell provided by this invention has an electron transport layer made of N-type sulfides or selenides, which has excellent electron mobility and is beneficial to improving the efficiency of the perovskite solar cell. At the same time, the electron transport layer is made of inorganic materials, which not only has a lower cost, but also can effectively block water vapor in the environment, improve the stability of the perovskite solar cell, and extend the life of the perovskite solar cell. Attached Figure Description

[0021] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0022] Figure 1 A schematic diagram of the deposition of the electron transport layer provided in an embodiment of the present invention;

[0023] Explanation of reference numerals in the attached figures:

[0024] 1 – Deposition chamber; 2 – Substrate holder; 3 – Ion source; 4 – Substrate; 5 – Target material; 6 – Support; 7 – Exhaust port. Detailed Implementation

[0025] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0026] In the description of this invention, it should be noted that the terms "center," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0027] This embodiment provides a method for fabricating a perovskite solar cell, which uses ion-assisted deposition technology to form an electron transport layer; wherein, the angle formed between the direction from the center of the target material to the center of the substrate and the emission direction of the ion beam is greater than or equal to 90° and less than 180°, the target material is at least one of sulfide or selenide, and the conduction band bottom of the target material is lower than the conduction band bottom of the perovskite layer.

[0028] The aforementioned method for fabricating perovskite solar cells limits the angle between the direction from the target center to the substrate center and the emission direction of the ion beam to be greater than or equal to 90° and less than 180°. This ensures that the gaseous material to be deposited from the target is bombarded by the ion beam as it moves towards the substrate, resulting in energy loss. This prevents damage to the functional layers below the electron transport layer, especially the organic functional layers, due to the high energy of the material to be deposited, thus guaranteeing the efficiency of the perovskite solar cell. Simultaneously, it makes the cations and anions in the gaseous material more reactive, leading to their separation. Compared to cations, sulfur or selenium ions are more easily lost, further enhancing the recombination of anions and cations. The absence of sulfur or selenium ions after recombination results in an N-type sulfide or selenide material for the electron transport layer, which improves the electron mobility of the electron transport layer and thus enhances the efficiency of perovskite solar cells. Furthermore, the inorganic material of the electron transport layer not only has lower cost but also effectively blocks moisture from the environment, improving the stability and extending the lifespan of the perovskite solar cells. In addition, the electron transport layer is formed using ion-assisted deposition technology, which is simple to prepare and suitable for large-scale commercial production. In summary, the perovskite solar cell preparation method provided by this invention easily balances processing efficiency with battery performance.

[0029] For details, see Figure 1 The deposition chamber 1 is provided with a substrate holder 2 and an ion source 3. The substrate holder 2 is movable, and the substrate 4 is adapted to be fixed on the substrate holder 2. The target material 5 is adapted to be placed directly below the substrate 4. The ion source 3 is fixed in the deposition chamber 1 by a bracket 6. The ion source 3 is located on the side of the substrate 4 and the side of the target material 5, but is not placed between the substrate 4 and the target material 5. The ion source 3 is adapted to emit an ion beam into the area between the substrate 4 and the target material 5. The side wall of the deposition chamber 1 is also provided with an air extraction port 7, so as to evacuate the deposition chamber 1 by vacuum pump or other vacuum equipment.

[0030] It is important to understand that sulfides or selenides that do not lose anions have high insulation properties, resulting in low electron mobility. When oxides (such as TiO2 or SnO2) are used as electron transport materials, the preparation method provided in this embodiment is not applicable. This is because the preparation process of oxides involves a high oxygen partial pressure, resulting in excess oxygen atoms in the prepared electron transport layer, which oxidizes the perovskite and causes the battery to fail.

[0031] Specifically, the sulfides include, but are not limited to, Bi₂S₃, In₂S₃, TiS₂, and SnS₂; the selenides include, but are not limited to, CdSe, ZnSe, and In₂Se₃. When the target material is Bi₂S₃, the material of the prepared electron transport layer is Bi₂S₃. x x is greater than 0 and less than 3; when the target material is TiS2, the material of the prepared electron transport layer is TiS2.y y is greater than 0 and less than 2; when the target material is CdSe, the material of the prepared electron transport layer is CdSe. z z is greater than 0 and less than 1.

[0032] As a preferred embodiment, see below. Figure 1 The direction from the center of the target material to the center of the substrate is perpendicular to the emission direction of the ion beam.

[0033] Furthermore, the deposition rate of the electron transport layer is For example, the deposition rate of the electron transport layer can be or When the deposition rate of the electron transport layer is too low, the time required to deposit the electron transport layer is long; when the deposition rate of the electron transport layer is too high, the deposition quality of the electron transport layer cannot be guaranteed, thus affecting the electron transport effect of the electron transport layer and consequently affecting the efficiency of the perovskite solar cell. By limiting the deposition rate of the electron transport layer as described above, the deposition time is controlled while ensuring the deposition quality of the electron transport layer.

[0034] Furthermore, the thickness of the electron transport layer is 2nm-25nm. For example, the thickness of the electron transport layer is 2nm, 5nm, 8nm, 10nm, 11nm, 14nm, 15nm, 17nm, 20nm, 22nm, 23nm, or 25nm.

[0035] In this embodiment, during the deposition of the electron transport layer, the flow rate of the working gas introduced into the ion source is 10 sccm-100 sccm; the operating voltage of the ion source is 100V-2000V; and the operating current of the ion source is 0.1A-2A. The working gas is an inert gas, including but not limited to argon. For example, the flow rate of the working gas introduced into the ion source can be 10 sccm, 20 sccm, 30 sccm, 40 sccm, 50 sccm, 60 sccm, 70 sccm, 80 sccm, 90 sccm, or 100 sccm; the operating voltage of the ion source can be 100V, 125V, 150V, 175V, 200V, 250V, 500V, 750V, 1000V, 1250V, 1500V, 1750V, or 2000V; and the operating current of the ion source can be 0.1A, 0.25A, 0.5A, 0.75A, 1A, 1.25A, 1.5A, 1.75A, or 2A.

[0036] In this embodiment, the process for forming the gaseous deposit includes magnetron sputtering, thermal evaporation deposition, and electron beam evaporation. The process parameters for forming the gaseous deposit using thermal evaporation deposition include: a target current of 0.1A-10A and a target voltage of 200V-300V. For example, the target current can be 0.1A, 1A, 2A, 3A, 4A, 5A, 6A, 7A, 8A, 9A, or 10A, and the target voltage can be 200V, 210V, 220V, 230V, 240V, 250V, 260V, 270V, 280V, 290V, or 300V.

[0037] Furthermore, during the deposition of the electron transport layer, the atmosphere in the deposition chamber is an inert atmosphere, and the deposition chamber is in a vacuum state; specifically, the inert atmosphere includes, but is not limited to, an argon atmosphere, and the vacuum degree of the deposition chamber does not exceed 1.0 Pa.

[0038] In a preferred embodiment, the perovskite solar cell is an inverted perovskite solar cell. An inverted perovskite solar cell comprises a substrate, a transparent conductive layer, a hole transport layer, a perovskite layer, an electron transport layer, and a metal electrode, stacked sequentially. The substrate material includes, but is not limited to, glass; the transparent conductive layer material includes, but is not limited to, FTO or ITO; the hole transport layer is an organic hole transport material or an inorganic hole transport material, and the inorganic hole transport material includes, but is not limited to, NiO. x Cu2O, NiMgO x NiO x The thickness of the layer is 15nm-25nm, and the thickness of the Cu2O layer is 20nm-30nm. For example, NiO... x The thickness of the layer can be 15nm, 16nm, 17nm, 18nm, 19nm, 20nm, 21nm, 22nm, 23nm, 24nm or 25nm, and the thickness of the Cu2O layer can be 20nm, 21nm, 22nm, 23nm, 24nm, 25nm, 26nm, 27nm, 28nm, 29nm or 30nm; the materials of the perovskite layer include, but are not limited to, CsFAPbI3, CsFAPbBr3, MAPbI3, MASnBr3, and the thickness of the perovskite layer is 300nm-600nm. For example, the thickness of the perovskite layer can be 300nm, 350nm, 400nm, 450nm, 500nm, 550nm or 600nm; the materials of the metal electrode include, but are not limited to, gold and silver.

[0039] Furthermore, the fabrication method of the inverted perovskite solar cell includes: sequentially depositing a transparent conductive layer, a hole transport layer, and a perovskite layer on a substrate, then forming an electron transport layer on the surface of the perovskite layer, and subsequently forming a metal electrode on the surface of the electron transport layer. Considering the fabrication cost and industrial production, the hole transport material is preferably an inorganic hole transport material, and it is prepared using a vapor deposition process; the fabrication process of the perovskite layer includes, but is not limited to, spin coating and blade coating, wherein the spin coating process can be a one-step or two-step method; the fabrication process of the metal electrode includes, but is not limited to, vacuum evaporation.

[0040] It is important to understand that, since the electron transport layer is deposited on the perovskite layer, the selection of electron transport materials and processing methods must be carefully chosen to avoid damaging the perovskite layer during deposition. Currently, the electron transport layer in inverted perovskite solar cells is typically an organic material layer or an organic composite material layer. Materials for organic material layers include, but are not limited to, PCBM ([6,6]-phenyl-C61-butyric acid methyl ester), and materials for organic composite material layers include C... 60 The perovskite solar cell has two main characteristics: an electron transport layer and a BCP layer. On the one hand, organic materials have poor water resistance, leading to a short lifespan for perovskite solar cells. On the other hand, these organic materials are expensive, and the deposition process for the electron transport layer is complex and requires high equipment costs, making them unsuitable for large-scale commercial production. However, the method and materials used in this embodiment for fabricating the electron transport layer in an inverted perovskite solar cell not only extend the lifespan of the perovskite solar cell and prevent damage to the perovskite layer during fabrication, thus ensuring the efficiency of the perovskite solar cell, but also reduce fabrication costs and difficulty, making it suitable for large-scale commercial production.

[0041] This embodiment also provides a perovskite solar cell, including an electron transport layer made of N-type sulfides or selenides. The aforementioned perovskite solar cell exhibits excellent electron mobility, which is beneficial for improving its efficiency. Furthermore, the electron transport layer is made of inorganic materials, which not only reduces cost but also effectively blocks moisture from the environment, improving the stability and extending the lifespan of the perovskite solar cell.

[0042] Specifically, the sulfides include, but are not limited to, Bi₂S₃, In₂S₃, TiS₂, and SnS₂; the selenides include, but are not limited to, CdSe, ZnSe, and In₂Se₃. For example, the material of the electron transport layer is Bi₂S₃. x TiS y Or CdSe z x is greater than 0 and less than 3, y is greater than 0 and less than 2, and z is greater than 0 and less than 1.

[0043] Furthermore, the thickness of the electron transport layer is 2nm-25nm. For example, the thickness of the electron transport layer is 2nm, 5nm, 8nm, 10nm, 11nm, 14nm, 15nm, 17nm, 20nm, 22nm, 23nm, or 25nm.

[0044] In a preferred embodiment, the perovskite solar cell is an inverted perovskite solar cell.

[0045] The following section uses the thermal evaporation deposition process to form the deposit as an example to provide a clear and complete explanation of perovskite solar cells and their preparation methods.

[0046] Example 1

[0047] This embodiment provides a perovskite solar cell, which includes sequentially stacked FTO conductive glass, a hole transport layer, a perovskite layer, an electron transport layer, and an Ag electrode. The area of ​​the FTO conductive glass is 1 cm². 2 The hole transport layer is made of NiO. x The thickness of the perovskite layer is 20 nm; the material of the perovskite layer is CsFAPbI3, and the thickness is 500 nm; the material of the electron transport layer is Bi2S. x The thickness is 2nm.

[0048] This embodiment also provides a method for preparing the above-mentioned perovskite solar cell, including:

[0049] A hole transport layer was deposited on FTO conductive glass using a vacuum evaporation process.

[0050] A perovskite layer was formed on the surface of the hole transport layer using a one-step method to obtain the substrate;

[0051] The substrate and Bi2S3 target were placed in the deposition chamber, and the ion source was adjusted to ensure that the emission direction of the ion beam was perpendicular to the direction from the center of the target to the center of the substrate. The deposition chamber was then evacuated until the vacuum level reached 2.0*10. -3 After Pa, argon gas is introduced into the deposition chamber at a flow rate of 5 sccm, and the vacuum level in the deposition chamber is controlled at 5.0 × 10⁻⁶. -2 Pa; The target is energized with a current of 0.1 A and a voltage of 200 V; the ion source is turned on and argon gas is introduced into the ion source at a flow rate of 10 sccm, with a voltage of 100 V and a current of 0.5 A; the deposition rate of the electron transport layer in the ion source is... The thickness of the electron transport layer deposited is 2 nm; the ion source is powered off and the gas supply to the ion source is stopped;

[0052] Ag electrodes are deposited on the surface of the electron transport layer using a vacuum evaporation process.

[0053] Example 2

[0054] This embodiment provides a perovskite solar cell, which differs from the perovskite solar cell provided in Embodiment 1 in that the thickness of the electron transport layer is 5 nm, and the thickness of the electron transport layer is controlled by the deposition time.

[0055] Example 3

[0056] This embodiment provides a perovskite solar cell, which differs from the perovskite solar cell provided in Embodiment 1 in that the thickness of the electron transport layer is 8 nm, and the thickness of the electron transport layer is controlled by the deposition time.

[0057] Example 4

[0058] This embodiment provides a perovskite solar cell, which differs from the perovskite solar cell provided in Embodiment 1 in that the thickness of the electron transport layer is 11 nm, and the thickness of the electron transport layer is controlled by the deposition time.

[0059] Example 5

[0060] This embodiment provides a perovskite solar cell, which differs from the perovskite solar cell provided in Embodiment 1 in that the thickness of the electron transport layer is 14 nm, and the thickness of the electron transport layer is controlled by the deposition time.

[0061] Example 6

[0062] This embodiment provides a perovskite solar cell, which differs from the perovskite solar cell provided in Embodiment 1 in that the thickness of the electron transport layer is 17 nm, and the thickness of the electron transport layer is controlled by the deposition time.

[0063] Example 7

[0064] This embodiment provides a perovskite solar cell, which includes sequentially stacked FTO conductive glass, a hole transport layer, a perovskite layer, an electron transport layer, and an Ag electrode. The area of ​​the FTO conductive glass is 1 cm². 2 The hole transport layer is made of Cu2O and has a thickness of 24 nm; the perovskite layer is made of MAPbI3 and has a thickness of 420 nm; and the electron transport layer is made of CdSe and has a thickness of 2 nm.

[0065] This embodiment also provides a method for preparing the above-mentioned perovskite solar cell, including:

[0066] A hole transport layer was deposited on FTO conductive glass using a vacuum evaporation process.

[0067] A perovskite layer was formed on the surface of the hole transport layer using a one-step method to obtain the substrate;

[0068] The substrate and Bi2S3 target were placed in the deposition chamber, and the ion source was adjusted to ensure that the emission direction of the ion beam was perpendicular to the direction from the center of the target to the center of the substrate. The deposition chamber was then evacuated until the vacuum level reached 2.0*10. -3 After Pa, argon gas is introduced into the deposition chamber at a flow rate of 20 sccm, and the vacuum level in the deposition chamber is controlled at 1.0 × 10⁻⁶. -1 Pa; The target is energized with a current of 10 A and a voltage of 300 V; the ion source is turned on and argon gas is introduced into the ion source at a flow rate of 100 sccm, with a voltage of 200 V and a current of 0.6 A; the deposition rate of the electron transport layer in the ion source is... The thickness of the electron transport layer deposited is 2 nm; the ion source is powered off and the gas supply to the ion source is stopped;

[0069] Ag electrodes are deposited on the surface of the electron transport layer using a vacuum evaporation process.

[0070] Example 8

[0071] This embodiment provides a perovskite solar cell, which differs from the perovskite solar cell provided in Embodiment 7 in that the thickness of the electron transport layer is 5 nm, and the thickness of the electron transport layer is controlled by the deposition time.

[0072] Example 9

[0073] This embodiment provides a perovskite solar cell, which differs from the perovskite solar cell provided in Embodiment 7 in that the thickness of the electron transport layer is 8 nm, and the thickness of the electron transport layer is controlled by the deposition time.

[0074] Example 10

[0075] This embodiment provides a perovskite solar cell, which differs from the perovskite solar cell provided in Embodiment 7 in that the thickness of the electron transport layer is 11 nm, and the thickness of the electron transport layer is controlled by the deposition time.

[0076] Example 11

[0077] This embodiment provides a perovskite solar cell, which differs from the perovskite solar cell provided in Embodiment 7 in that the thickness of the electron transport layer is 14 nm, and the thickness of the electron transport layer is controlled by the deposition time.

[0078] Example 12

[0079] This embodiment provides a perovskite solar cell, which differs from the perovskite solar cell provided in Embodiment 7 in that the thickness of the electron transport layer is 17 nm, and the thickness of the electron transport layer is controlled by the deposition time.

[0080] Example 13

[0081] This embodiment provides a perovskite solar cell, which differs from the perovskite solar cell provided in Embodiment 7 in that the thickness of the electron transport layer is 20 nm, and the thickness of the electron transport layer is controlled by the deposition time.

[0082] Example 14

[0083] This embodiment provides a perovskite solar cell, which differs from the perovskite solar cell provided in Embodiment 7 in that the thickness of the electron transport layer is 23 nm, and the thickness of the electron transport layer is controlled by the deposition time.

[0084] Test case

[0085] The photoelectric performance of the perovskite solar cells provided in Examples 1-14 was tested. The test results are shown in Table 1:

[0086] Table 1

[0087] Efficiency (%) Voc(V) Fill Factor (%) Jsc(mA / cm^2) Rs(ohm) Rsh(ohm) Example 1 13.37 0.84 65.31 24.40 7.40 6005.73 Example 2 14.58 0.86 68.48 24.84 6.64 2028.88 Example 3 13.67 0.83 67.53 24.44 6.55 6405.60 Example 4 11.14 0.90 50.30 24.65 12.36 2110.61 Example 5 10.13 0.88 47.65 24.21 16.20 245.61 Example 6 8.80 0.86 41.49 24.73 35.88 1062.94 Example 7 9.91 0.89 46.15 24.11 13.35 1147.27 Example 8 12.02 0.77 63.91 24.28 7.95 983.47 Example 9 14.49 0.83 68.98 25.20 6.50 3942.44 Example 10 15.33 0.88 70.01 24.88 6.84 1015.45 Example 11 13.66 0.84 66.30 24.65 7.35 2430.80 Example 12 12.64 0.81 63.77 24.56 7.55 652.16 Example 13 10.51 0.89 43.29 23.82 13.68 371.63 Example 14 7.61 0.94 33.41 22.61 25.61 192.59

[0088] As shown in Table 1, the perovskite solar cells provided in Examples 1-14 have excellent performance.

[0089] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A method for preparing a perovskite solar cell, characterized in that, An electron transport layer is formed on one side surface of the functional layer using ion-assisted deposition technology; wherein the angle between the direction from the center of the target to the center of the substrate and the emission direction of the ion beam is greater than or equal to 90° and less than 180°, the target is at least one of sulfide or selenide, and the conduction band bottom of the target is lower than the conduction band bottom of the perovskite layer.

2. The method for preparing a perovskite solar cell according to claim 1, characterized in that, The direction from the center of the target material to the center of the substrate is perpendicular to the emission direction of the ion beam.

3. The method for preparing a perovskite solar cell according to claim 1, characterized in that, The deposition rate of the electron transport layer is 4. The method for preparing a perovskite solar cell according to claim 3, characterized in that, The thickness of the electron transport layer is 2nm-25nm.

5. The method for preparing a perovskite solar cell according to any one of claims 1 to 4, characterized in that, During the deposition of the electron transport layer, the flow rate of the working gas introduced into the ion source is 10 sccm-100 sccm; the operating voltage of the ion source is 100V-2000V; and the operating current of the ion source is 0.1A-2A.

6. The method for preparing a perovskite solar cell according to claim 5, characterized in that, The working gas is an inert gas.

7. The method for preparing a perovskite solar cell according to any one of claims 1 to 4, characterized in that, The process of forming a gaseous deposit from the target material includes magnetron sputtering, thermal evaporation deposition, and electron beam evaporation.

8. The method for preparing a perovskite solar cell according to claim 7, characterized in that, The process parameters for forming a gaseous material to be deposited using thermal evaporation deposition include: the current of the target material is 0.1A-10A, and the voltage of the target material is 200V-300V.

9. The method for preparing a perovskite solar cell according to any one of claims 1 to 4, characterized in that, During the deposition of the electron transport layer, the atmosphere in the deposition chamber is an inert atmosphere.

10. The method for preparing a perovskite solar cell according to any one of claims 1 to 4, characterized in that, The perovskite solar cell is an inverted perovskite solar cell.

11. The method for preparing a perovskite solar cell according to any one of claims 1 to 4, characterized in that, The sulfides include Bi2S3, In2S3, TiS2, and SnS2; the selenides include CdSe, ZnSe, and In2Se3.

12. A perovskite solar cell, comprising an electron transport layer, characterized in that, The electron transport layer is made of N-type sulfide or selenide, and the perovskite solar cell is prepared by the preparation method described in any one of claims 1-11.

Images