Preparation method of hole transport layer, perovskite solar cell and preparation method thereof
By preparing a hole transport layer through multi-step magnetron sputtering and annealing, the problem of poor compactness was solved, and the electrical performance of perovskite solar cells was improved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- SHENZHEN MANST TECH CO LTD
- Filing Date
- 2023-09-08
- Publication Date
- 2026-07-07
Smart Images
Figure CN117295379B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of perovskite solar cell technology, specifically to a method for preparing a hole transport layer, a perovskite solar cell, and the same method. Background Technology
[0002] Currently, the highest photoelectric conversion efficiency of single-junction perovskite solar cells has reached 25.7%, approaching the highest efficiency of crystalline silicon solar cells. For perovskite solar cells to be industrially mass-produced, in addition to high-quality perovskite films, high-performance carrier transport layer materials are also crucial. Nickel oxide (NiOx), as one of the most effective hole transport layer materials for perovskite solar cells, possesses a relatively high work function (approximately 5.4 eV) and a relatively large bandgap (3.6-4.0 eV), exhibiting high light transmittance in the near-ultraviolet and visible light bands. The valence band top of the NiOx film is well-matched with that of the perovskite film (CH3NH3PbI3), allowing photoexcited holes in the perovskite solar cell to smoothly transfer to the hole transport layer without electrons transferring to NiOx.
[0003] The structure of inverted (pin) perovskite solar cells is the mainstream mass production technology, typically consisting of a stacked transparent conductive layer, a hole transport layer, a perovskite light-absorbing layer, an electron transport layer, and a metal electrode layer. Mass production generally employs continuous deposition lines, essentially using the magnetron sputtering process to form the hole transport layer from NiOx thin films. This results in a poorly dense hole transport layer.
[0004] In view of the above circumstances, the present invention is hereby proposed. Summary of the Invention
[0005] Therefore, the technical problem to be solved by the present invention is that the poor density of the hole transport layer in the prior art leads to poor electrical performance of perovskite solar cells, thereby providing a method for preparing a hole transport layer, a perovskite solar cell and the same method.
[0006] This invention provides a method for preparing a hole transport layer, and provides an apparatus comprising: a continuously arranged feed chamber (A), a coating chamber (B), a vacuum annealing chamber (C), a nitrogen annealing chamber (D), and a discharge chamber (E); the coating chamber (B) includes a continuously arranged first chamber (B1) and a second chamber (B2); the method includes: providing a conductive substrate (1); the feed chamber (A) being adapted to place the provided conductive substrate (1); conveying the conductive substrate (1) to the first chamber (B1) to form a first initial hole transport layer on one side surface of the conductive substrate (1); after forming the first initial hole transport layer, conveying the conductive substrate (1) to the second chamber (B2) to form a hole transport layer on one side surface of the first initial hole transport layer away from the first initial hole transport layer. A second initial hole transport layer is formed on one side surface of the conductive substrate (1). After the second initial hole transport layer is formed, the conductive substrate (1) is transferred to a vacuum annealing chamber (C) and / or a nitrogen annealing chamber (D) to perform vacuum annealing and / or nitrogen annealing treatment on the first initial hole transport layer and the second initial hole transport layer, so that the first initial hole transport layer forms a first hole transport layer (21), and the second initial hole transport layer forms a second hole transport layer (22) and a third hole transport layer (23). During the process of the conductive substrate (1) being transferred to the first chamber (B1), the second chamber (B2), and the vacuum annealing chamber (C) and / or the nitrogen annealing chamber (D), the conductive substrate (1) is placed in a vacuum environment.
[0007] Optionally, during the vacuum annealing process, the pressure in the vacuum annealing chamber gradually decreases; at the start of the vacuum annealing process, the pressure is less than or equal to 10. -1 Pa, when the vacuum annealing process ends, the pressure is less than or equal to 10 Pa. -2 Pa; the temperature of the vacuum annealing treatment is 200℃-400℃, and the time of the vacuum annealing treatment is 100s-1000s.
[0008] Optionally, during nitrogen annealing, the pressure in the nitrogen annealing chamber (D) gradually increases; at the start of nitrogen annealing, the pressure is greater than or equal to 10. -3 Pa, when the nitrogen annealing process ends, the pressure is greater than or equal to 10 Pa. -2 Pa; the nitrogen annealing temperature is 200℃-400℃, and the nitrogen annealing time is 100s-1000s.
[0009] Optionally, the step of forming a first initial hole transport layer on one side surface of the conductive substrate (1) includes: introducing argon gas into the first chamber; performing magnetron sputtering using a radio frequency power supply; the power of the radio frequency power supply being 1kW-5kW; and the temperature of the first chamber being 200℃-400℃.
[0010] Optionally, the step of forming a second initial hole transport layer on the side of the first initial hole transport layer away from the conductive substrate (1) includes: introducing argon gas into the second chamber; performing magnetron sputtering using a radio frequency power supply; the power of the radio frequency power supply being 3kW-10kW; and the temperature of the second chamber being 150℃-350℃.
[0011] Optionally, it also includes: providing a heating system for heating the side surface of the conductive substrate (1) away from the first initial hole transport layer.
[0012] Optionally, before forming a first initial hole transport layer on one side surface of the conductive substrate (1), the conductive substrate (1) is subjected to vacuum preheating treatment; the temperature of the vacuum preheating treatment is 100℃-200℃; and the time of the vacuum preheating treatment is 400s-800s.
[0013] The present invention also provides a method for fabricating a perovskite solar cell, comprising: the method for fabricating a hole transport layer as described in the present invention; the conductive substrate (1) includes a substrate (11) and a transparent conductive layer (12) located on one side surface of the substrate (11); after forming a first hole transport layer (21) on one side surface of the conductive substrate (1), the transparent conductive layer (12) is located between the substrate (11) and the first hole transport layer (21); further comprising: forming a perovskite absorption layer (3) on the side surface of the third hole transport layer (23) away from the conductive substrate (1); forming an electron transport layer (4) on the side surface of the perovskite absorption layer (3) away from the conductive substrate (1); and forming a metal electrode layer (5) on the side surface of the electron transport layer away from the conductive substrate (1).
[0014] This invention also provides a perovskite solar cell, prepared using the perovskite solar cell preparation method described in this invention; comprising: a conductive substrate (1); a first hole transport layer (21) located on one side surface of the conductive substrate (1); a second hole transport layer (22) located on the side of the first hole transport layer (21) away from the conductive substrate (1); and a third hole transport layer (23) located on the side of the second hole transport layer (22) away from the conductive substrate (1); wherein, the conductive substrate (1) includes a substrate ( 11) and a transparent conductive layer (12) located on one side surface of the substrate (11), the transparent conductive layer (12) being located between the substrate (11) and the first hole transport layer (21); further comprising: a perovskite absorption layer (3) located on the side of the third hole transport layer (23) away from the conductive substrate (1); an electron transport layer (4) located on the side of the perovskite absorption layer (3) away from the conductive substrate (1); and a metal electrode layer (5) located on the side of the electron transport layer (4) away from the conductive substrate (1).
[0015] Optionally, the thickness of the first hole transport layer (21) is 5nm-8nm, the thickness of the second hole transport layer (22) is 10nm-15nm, and the thickness of the third hole transport layer (23) is 2nm-4nm.
[0016] Optionally, the first hole transport layer (21) includes a first NiOx layer, the second hole transport layer (22) includes a second NiOx layer, and the third hole transport layer (23) includes a third NiOx layer.
[0017] The technical solution of this invention has the following advantages:
[0018] The primary objective of this invention is to provide a method for preparing a hole transport layer, which, compared to conventional methods:
[0019] 1. After forming a first initial hole transport layer on one side surface of the conductive substrate (1), a second initial hole transport layer is formed on the side surface of the first initial hole transport layer away from the conductive substrate (1). This ensures the adhesion between the first initial hole transport layer and the conductive substrate (1) and facilitates the high-speed fabrication of the second initial hole transport layer. After forming the second initial hole transport layer on the side surface of the first initial hole transport layer away from the conductive substrate (1), the first initial hole transport layer and the second initial hole transport layer are subjected to vacuum annealing and / or nitrogen annealing, so that the first initial hole transport layer forms a first hole transport layer (21), the second initial hole transport layer forms a second hole transport layer (22), and the third hole transport layer (23). After vacuum annealing and / or nitrogen annealing, the density of the first hole transport layer (21), the second hole transport layer (22), and the third hole transport layer (23) is improved to varying degrees, thereby improving the overall density of the hole transport layer. Among them, the first initial hole transport layer is between the second initial hole transport layer and the conductive substrate (1). The annealing effect of the first initial hole transport layer is small, and the effect of increasing the density of the first hole transport layer (21) is small. However, the density of the surface and near-surface of the second initial hole transport layer is significantly improved. The density change inside the second initial hole transport layer is smaller than the density change on the surface of the second initial hole transport layer. Therefore, the part with low density obtained by annealing is divided into the second hole transport layer (22), and the part with high density on the surface is divided into the third hole transport layer (23). Specifically, after vacuum annealing and / or nitrogen annealing, the density of the second hole transport layer (22) is increased by at least 5%-10% and the density of the third hole transport layer (23) is increased by at least 7%-12%.
[0020] 2. During the process of transferring the conductive substrate (1) to the first chamber (B1), the second chamber (B2), and the vacuum annealing chamber (C) and / or the nitrogen annealing chamber (D), the conductive substrate (1) is always placed in a vacuum environment. This prevents the surface of the conductive substrate (1) from adsorbing atmospheric air and moisture, and also prevents the loose surfaces of the first and second initial hole transport layers from adsorbing atmospheric air and moisture. During vacuum annealing and / or nitrogen annealing, it completely avoids chemical reactions between the adsorbed atmospheric air and moisture at high temperatures and the first and second initial hole transport layers (leading to film deterioration). It also prevents the adsorbed atmospheric air and moisture from carrying away excessive heat during annealing, thus affecting the annealing effect of the hole transport layer. Therefore, during the preparation of the hole transport layer, the conductive substrate (1) is always placed in a vacuum environment, which is beneficial for improving the overall density of the hole transport layer after vacuum annealing and / or nitrogen annealing.
[0021] 3. The power of the radio frequency power supply used to form the first initial hole transport layer is less than that used to form the second initial hole transport layer. The purpose is that: because the ion bombardment of the conductive substrate (1) is strong during magnetron sputtering, the deposition rate is low when using a low-power radio frequency power supply for magnetron sputtering, which can improve the adhesion between the first initial hole transport layer and the conductive substrate (1); using a high-power radio frequency power supply for magnetron sputtering on the basis of the first initial hole transport layer can improve the formation rate of the second initial hole transport layer and reduce the number of targets.
[0022] 4. Before forming the first initial hole transport layer on one side surface of the conductive substrate (1), the conductive substrate (1) is subjected to vacuum preheating treatment. The purpose is to fully release the impurity gases and moisture adsorbed by the conductive substrate in the atmospheric environment and improve the cleanliness of the surface of the conductive substrate (1).
[0023] The second objective of this invention is to provide a method for preparing a perovskite solar cell. The hole transport layer (2) formed by combining the first hole transport layer (21), the second hole transport layer (22), and the third hole transport layer (23) using the above-mentioned hole transport layer preparation method has good overall compactness, enhances the collection and transport capability of hole carriers, reduces the potential interface recombination loss between the hole transport layer (2) and the subsequently formed perovskite absorber layer (3), promotes the energy level arrangement of the interface between the perovskite absorber layer (3) and the hole transport layer (2), and also enhances the hole extraction efficiency, thereby improving the short-circuit current and fill factor of the perovskite solar cell and improving the electrical performance of the perovskite solar cell. Furthermore, the hole transport layer after two-step magnetron sputtering deposition, vacuum annealing, and / or nitrogen annealing improves the quality of the perovskite absorber layer (3) and enhances its crystallinity, increases the grain size, and thus realizes the preparation and production of high-efficiency perovskite solar cells. Attached Figure Description
[0024] 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.
[0025] Figure 1 A flowchart illustrating the method for preparing a hole transport layer according to an embodiment of the present invention;
[0026] Figure 2 This is a schematic diagram of the device used in the method for preparing a hole transport layer according to an embodiment of the present invention;
[0027] Figure 3 This is a schematic diagram of the structure of a perovskite solar cell provided in an embodiment of the present invention. Detailed Implementation
[0028] 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.
[0029] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "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," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.
[0030] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; 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; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.
[0031] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.
[0032] This embodiment provides a method for preparing a hole transport layer, and provides an apparatus comprising: a continuously arranged feeding chamber (A), a coating chamber (B), a vacuum annealing chamber (C), a nitrogen annealing chamber (D), and a discharge chamber (E); the coating chamber (B) comprises a continuously arranged first chamber (B1) and a second chamber (B2); Reference Figure 1 and Figure 2 ,include:
[0033] S1: Provide a conductive substrate (1); the feed chamber (A) is adapted to hold the provided conductive substrate (1);
[0034] S2: The conductive substrate (1) is transferred to the first chamber (B1) to form a first initial hole transport layer on one side surface of the conductive substrate (1);
[0035] S3: After forming the first initial hole transport layer, the conductive substrate (1) is transferred to the second chamber (B2) to form a second initial hole transport layer on the side surface of the first initial hole transport layer away from the conductive substrate (1).
[0036] S4: After forming the second initial hole transport layer, the conductive substrate (1) is transferred to a vacuum annealing chamber (C) and / or a nitrogen annealing chamber (D) to perform vacuum annealing and / or nitrogen annealing on the first initial hole transport layer and the second initial hole transport layer, so that the first initial hole transport layer forms the first hole transport layer (21), and the second initial hole transport layer forms the second hole transport layer (22) and the third hole transport layer (23);
[0037] During the process of transferring the conductive substrate (1) to the first chamber (B1), the second chamber (B2), and the vacuum annealing chamber (C) and / or the nitrogen annealing chamber (D), the conductive substrate (1) is placed in a vacuum environment.
[0038] In this embodiment, after forming a first initial hole transport layer on one side surface of the conductive substrate (1), a second initial hole transport layer is formed on the side surface of the first initial hole transport layer away from the conductive substrate (1). This ensures the adhesion between the first initial hole transport layer and the conductive substrate (1) and facilitates the high-speed fabrication of the second initial hole transport layer. After forming the second initial hole transport layer on the side surface of the first initial hole transport layer away from the conductive substrate (1), the first initial hole transport layer and the second initial hole transport layer are subjected to vacuum annealing and / or nitrogen annealing, so that the first initial hole transport layer forms a first hole transport layer (21), the second initial hole transport layer forms a second hole transport layer (22), and the third hole transport layer (23). After vacuum annealing and / or nitrogen annealing, the density of the first hole transport layer (21), the second hole transport layer (22), and the third hole transport layer (23) is improved to varying degrees, thereby improving the overall density of the hole transport layer. Among them, the first initial hole transport layer is between the second initial hole transport layer and the conductive substrate (1). The annealing effect of the first initial hole transport layer is small, and the effect of increasing the density of the first hole transport layer (21) is small. However, the density of the surface and near-surface of the second initial hole transport layer is significantly improved. The density change inside the second initial hole transport layer is smaller than the density change on the surface of the second initial hole transport layer. Therefore, the part with low density obtained by annealing is divided into the second hole transport layer (22), and the part with high density on the surface is divided into the third hole transport layer (23). Specifically, after vacuum annealing and / or nitrogen annealing, the density of the second hole transport layer (22) is increased by at least 5%-10% and the density of the third hole transport layer (23) is increased by at least 7%-12%.
[0039] In addition, during the process of transferring the conductive substrate (1) to the first chamber (B1), the second chamber (B2), and the vacuum annealing chamber (C) and / or the nitrogen annealing chamber (D), the conductive substrate (1) is always placed in a vacuum environment. This prevents the surface of the conductive substrate (1) from adsorbing atmospheric air and moisture, and also prevents the loose surfaces of the first and second initial hole transport layers from adsorbing atmospheric air and moisture. During the vacuum annealing and / or nitrogen annealing processes, it completely avoids chemical reactions between the adsorbed atmospheric air and moisture at high temperatures and the first and second initial hole transport layers (leading to film deterioration). It also prevents the adsorbed atmospheric air and moisture from carrying away excessive heat during annealing, thus affecting the annealing effect of the hole transport layer. Therefore, during the preparation of the hole transport layer, the conductive substrate (1) is always placed in a vacuum environment, which is beneficial for improving the overall density of the hole transport layer after vacuum annealing and / or nitrogen annealing.
[0040] Furthermore, the hole transport layer (2) has good overall compactness. This further enhances the collection and transport capabilities of hole carriers, reduces the potential interface recombination loss between the hole transport layer (2) and the subsequently formed perovskite absorber layer (3), thereby improving the short-circuit current and fill factor of the perovskite solar cell and enhancing its electrical performance.
[0041] It should be noted that during the process of conveying the conductive substrate (1) to the first chamber (B1), the second chamber (B2), and the vacuum annealing chamber (C) and / or the nitrogen annealing chamber (D), the conductive substrate (1) is placed in a vacuum environment. That is to say, the conductive substrate (1) is not in contact with the outside atmosphere from the feeding chamber to the discharging chamber (E). It can be understood that during the process of conveying the conductive substrate (1) to the first chamber (B1), the conductive substrate (1) is not in contact with the outside atmosphere; during the process of forming the first initial hole transport layer on one side surface of the conductive substrate (1), the conductive substrate (1) and the first initial hole transport layer are not in contact with the outside atmosphere; during the process of conveying the conductive substrate (1) to the second chamber (B2), the conductive substrate (1) is not in contact with the outside atmosphere. Contact; the conductive substrate (1) and the first initial hole transport layer are not in contact with the outside atmosphere; during the formation of the second initial hole transport layer on the surface of the first initial hole transport layer away from the conductive substrate (1), the conductive substrate (1), the first initial hole transport layer and the second initial hole transport layer are not in contact with the outside atmosphere; during the transfer of the conductive substrate (1) to the vacuum annealing chamber (C) and / or the nitrogen annealing chamber (D), the conductive substrate (1), the first initial hole transport layer and the second initial hole transport layer are not in contact with the outside atmosphere; during the vacuum annealing treatment and / or nitrogen annealing treatment of the first initial hole transport layer and the second initial hole transport layer, the conductive substrate (1), the first initial hole transport layer and the second initial hole transport layer are not in contact with the outside atmosphere.
[0042] In this embodiment, the first initial hole transport layer includes a first initial NiOx layer, the first hole transport layer (21) includes a first NiOx layer, the second initial hole transport layer includes a second initial NiOx layer, the second hole transport layer (22) includes a second NiOx layer, and the third hole transport layer (23) includes a third NiOx layer.
[0043] In one embodiment, the conductive substrate (1) includes a substrate (11) and a transparent conductive layer (12) located on one side surface of the substrate; after a first hole transport layer (21) is formed on one side surface of the conductive substrate (1), the transparent conductive layer (12) is located between the substrate (11) and the first hole transport layer (21).
[0044] In one embodiment, the substrate (11) comprises a glass or flexible substrate.
[0045] In this embodiment, the transparent conductive layer (12) includes a TCO conductive layer. In other embodiments, the transparent conductive layer further includes at least one of an ITO conductive layer, an FTO conductive layer, and an AZO conductive layer.
[0046] In one embodiment, after forming the second initial hole transport layer, the conductive substrate (1) is transferred to a vacuum annealing chamber (C) to perform vacuum annealing on the first initial hole transport layer and the second initial hole transport layer. After vacuum annealing, the density of the second hole transport layer (22) is increased by 5%-10%, for example, by 5%, 6%, 7%, 8%, 9% or 10%, and the density of the third hole transport layer (23) is increased by 7%-12%, for example, by 7%, 8%, 9%, 10%, 11% or 12%.
[0047] In another embodiment, after forming the second initial hole transport layer, the conductive substrate (1) is transferred to a nitrogen annealing chamber (D) to perform nitrogen annealing on the first hole transport layer and the second initial hole transport layer. After nitrogen annealing, the density of the second hole transport layer (22) is increased by 8%-13%, for example, by 8%, 9%, 10%, 11%, 12% or 13%, and the density of the third hole transport layer (23) is increased by 10%-15%, for example, by 10%, 11%, 12%, 13%, 14% or 15%.
[0048] In another embodiment, after forming the second initial hole transport layer, the conductive substrate (1) is transferred to a vacuum annealing chamber (C) for vacuum annealing of the first and second initial hole transport layers. Then, the conductive substrate (1) is transferred to a nitrogen annealing chamber (D) for nitrogen annealing. After nitrogen annealing, the density of the second hole transport layer (22) is increased by 15%-20%, and the density of the third hole transport layer (23) is increased by 20%-25%. For example, the density of the second hole transport layer (22) is increased by 15%, 16%, 17%, 18%, 19%, or 20%, and the density of the third hole transport layer (23) is increased by 20%, 21%, 22%, 23%, 24%, or 25%.
[0049] It should be noted that vacuum annealing and nitrogen annealing have a small effect on the first hole transport layer (21) and can be ignored. Therefore, the change in the density of the first hole transport layer (21) will not be described in this application.
[0050] Packing density, also known as packing ratio or maximum space utilization, refers to the percentage of volume occupied by atoms in a unit cell, that is, the ratio of the volume of atoms contained in the unit cell to the volume of the unit cell. In this embodiment, the unit cell refers to the first hole transport layer (21), the second hole transport layer (22), or the third hole transport layer (23), that is, the first NiOx layer, the second NiOx layer, or the third NiOx layer; the atom refers to the Ni atoms and O atoms in the NiOx unit cell.
[0051] In one embodiment, during the vacuum annealing process, the pressure in the vacuum annealing chamber gradually decreases; at the start of the vacuum annealing process, the pressure is less than or equal to 10. -1 When the vacuum annealing process ends, the chamber pressure is less than or equal to 10 Pa. -2 Pa. Preferably, the pressure is less than or equal to 10 Pa when vacuum annealing begins. -2 When the vacuum annealing process ends, the chamber pressure is less than or equal to 10 Pa. -3 Pa.
[0052] It should be noted that during vacuum annealing, the pressure in the vacuum annealing chamber can be gradually decreased, or the vacuum level in the vacuum annealing chamber can be gradually increased. Specifically, the higher the pressure in the vacuum annealing chamber, the lower the vacuum level.
[0053] In one embodiment, the vacuum annealing temperature is 200℃-400℃, for example, 200℃, 300℃, or 400℃, and the vacuum annealing time is 100s-1000s, for example, 100s, 300s, 600s, 900s, or 1000s. Preferably, the vacuum annealing temperature is 300℃-400℃, for example, 300℃, 350℃, or 400℃, and the vacuum annealing time is 300s-600s, for example, 300s, 400s, 500s, or 600s.
[0054] In one embodiment, during nitrogen annealing, the pressure in the nitrogen annealing chamber (D) gradually increases; at the start of nitrogen annealing, the pressure is greater than or equal to 10. -3 Pa, when the nitrogen annealing process ends, the pressure is greater than or equal to 10 Pa. -2 Pa; preferably, the pressure is greater than or equal to 10 Pa when nitrogen annealing begins. -2 Pa, when the nitrogen annealing process ends, the pressure is greater than or equal to 10 Pa. -1 Pa.
[0055] It should be noted that during nitrogen annealing, the pressure in the nitrogen annealing chamber (D) can be gradually increased, or the vacuum level in the nitrogen annealing chamber (D) can be gradually decreased.
[0056] In one embodiment, the nitrogen annealing treatment is performed at a temperature of 200°C-400°C, for example, 200°C, 300°C, or 400°C, and for a duration of 100s-1000s, for example, 100s, 300s, 600s, 900s, or 1000s. Preferably, the nitrogen annealing treatment is performed at a temperature of 300°C-400°C, for example, 300°C, 350°C, or 400°C, and for a duration of 300s-600s, for example, 300s, 400s, 500s, or 600s.
[0057] In one embodiment, the step of forming a first hole transport layer (21) on one side surface of the conductive substrate 1 includes: introducing argon gas into the first chamber; and performing magnetron sputtering using a radio frequency power supply.
[0058] In one embodiment, the power of the radio frequency power supply is 1kW-5kW, for example, 1kW, 2kW, 3kW, 4kW or 5kW. Preferably, the power of the radio frequency power supply is 1kW-3kW, for example, 1kW, 2kW or 3kW.
[0059] In one embodiment, the temperature of the first chamber is 200°C-400°C, for example, 200°C, 300°C, or 400°C. Preferably, the temperature of the first chamber is 300°C-400°C, for example, 300°C, 350°C, or 400°C. Specifically, the first chamber is provided with a heater, and the set temperature of the heater is preferably 300°C-400°C, for example, 300°C, 350°C, or 400°C.
[0060] In one embodiment, the step of forming a second initial hole transport layer on the surface of the first initial hole transport layer away from the conductive substrate 1 includes: introducing argon gas into the second chamber; and performing magnetron sputtering using a radio frequency power supply.
[0061] In one embodiment, the power of the radio frequency power supply is 3kW-10kW, for example, 3kW, 4kW, 5kW, 6kW, 7kW, 8kW, 9kW or 10kW. Preferably, the power of the radio frequency power supply is 5kW-10kW, for example, 5kW, 6kW, 7kW, 8kW, 9kW or 10kW.
[0062] In one embodiment, the temperature of the second chamber is 150°C-350°C, for example, 150°C, 200°C, 250°C, 300°C, or 350°C. Preferably, the temperature of the first chamber is 250°C-350°C, for example, 250°C, 300°C, or 350°C. Specifically, the second chamber is provided with a heater, and the set temperature of the heater is preferably 250°C-350°C, for example, 250°C, 300°C, or 350°C.
[0063] In other embodiments, magnetron sputtering can be performed using a DC power supply or a medium-frequency power supply.
[0064] It should be noted that the power of the radio frequency power supply used to form the first initial hole transport layer is less than that used to form the second initial hole transport layer. The purpose of this is that, since the ion bombardment of the conductive substrate (1) is strong during magnetron sputtering, the deposition rate is low when using a low-power radio frequency power supply for magnetron sputtering, which can improve the adhesion between the first initial hole transport layer and the conductive substrate (1). Using a high-power radio frequency power supply for magnetron sputtering based on the first initial hole transport layer can improve the formation rate of the second initial hole transport layer and reduce the number of targets.
[0065] During the formation of the first initial hole transport layer and the second initial hole transport layer, the temperature of the side surface of the conductive substrate facing the first initial hole transport layer and the second initial hole transport layer is consistent with the temperature required to form the first initial hole transport layer and the second initial hole transport layer, so as to avoid thermal stress in the first initial hole transport layer and the second initial hole transport layer.
[0066] In one embodiment, a heating system is provided between the first chamber and the second chamber to reduce the increase in internal stress of the first initial hole transport layer caused by the decrease in temperature of the conductive substrate after the formation of the first initial hole transport layer, which is beneficial to improving the adhesion of the second initial hole transport layer. In other embodiments, it is not necessary to provide a heating system between the first chamber and the second chamber.
[0067] In one embodiment, during the process of forming a first initial hole transport layer on one side surface of the conductive substrate (1) and forming a second initial hole transport layer on the side surface of the first initial hole transport layer away from the conductive substrate (1), the method for fabricating a perovskite solar cell further includes: providing a heating system for heating the side surface of the conductive substrate (1) away from the first initial hole transport layer. Heating the side surface of the conductive substrate (1) away from the first initial hole transport layer using the heating system allows the temperature of the side surface of the conductive substrate away from the first initial hole transport layer to reach the temperature of the other side surface where the first initial hole transport layer or the second initial hole transport layer is about to be formed. This is more conducive to the adhesion between the first initial hole transport layer and the conductive substrate (1), and between the second initial hole transport layer and the first initial hole transport layer.
[0068] The formation of a first initial hole transport layer on one side surface of the conductive substrate (1) is performed in a first chamber (B1), and the formation of a second initial hole transport layer on the side surface of the first initial hole transport layer away from the conductive substrate (1) is performed in a second chamber (B2). It is understood that the provided heating system is disposed in the first chamber (B1) and / or the second chamber (B2); since the heating system is used to heat the side surface of the conductive substrate (1) away from the first initial hole transport layer, it is understood that the heating system is disposed on the side of the conductive substrate (1) away from the first initial hole transport layer.
[0069] In this embodiment, the heating system includes a heater. The heater is a conventional device in the art, and the temperature of the heating system can be adjusted according to the temperature of the side surface of the conductive substrate (1) away from the first initial hole transport layer, which will not be described in detail here.
[0070] Before forming the first initial hole transport layer on one side surface of the conductive substrate (1), the conductive substrate (1) is subjected to vacuum preheating treatment. The purpose is to fully release the impurity gases and moisture adsorbed by the conductive substrate in the atmospheric environment and improve the cleanliness of the surface of the conductive substrate (1).
[0071] Before forming a first initial hole transport layer on one side surface of the conductive substrate (1), the conductive substrate (1) is placed on the provided conductive substrate (1). Specifically, the conductive substrate (1) is subjected to vacuum preheating treatment in the feed chamber (A). In this embodiment, the feed chamber (A) is equipped with a heater, and the conductive substrate (1) is subjected to vacuum preheating treatment by the heater.
[0072] Heaters are conventional devices in this field and will not be described in detail here.
[0073] In one embodiment, the temperature of the vacuum preheating treatment is 100℃-200℃, for example, 100℃, 150℃, or 200℃; the time of the vacuum preheating treatment is 400s-800s, for example, 400s, 500s, 600s, 700s, or 800s. It is understood that the heater is set to the temperature of the vacuum preheating treatment.
[0074] In one embodiment, the feeding chamber (A) and the coating chamber (B), the coating chamber (B) and the vacuum annealing chamber (C), the vacuum annealing chamber (C) and the nitrogen annealing chamber (D), and the nitrogen annealing chamber (D) and the discharge chamber (E) are all controlled and connected by a gate valve 6. The feeding chamber (A) is adapted to hold the provided conductive substrate (1); the first chamber (B1) is adapted to form a first hole transport layer (21); the second chamber (B2) is adapted to form a second initial hole transport layer; the vacuum annealing chamber (C) is adapted to perform vacuum annealing on the second initial hole transport layer; and the nitrogen annealing chamber (D) is adapted to perform nitrogen annealing on the second hole transport layer (22) and the third hole transport layer (23).
[0075] In one embodiment, the device further includes: a buffer chamber and a transition chamber (not shown in the figure); located between the feeding chamber (A) and the coating chamber (B), between the coating chamber (B) and the vacuum annealing chamber (C), between the vacuum annealing chamber (C) and the nitrogen annealing chamber (D), and between the nitrogen annealing chamber (D) and the discharge chamber (E). The buffer chamber and the transition chamber are specifically connected via a gate valve 6.
[0076] The feed chamber (A) also includes a roughing pump assembly; the buffer chamber includes a valve, a molecular pump assembly, a roughing pump assembly, a heater, and an argon gas path; the transition chamber includes a valve, a heater, and an argon gas path; the buffer chamber includes a valve, a heater, and an argon gas path. The buffer chamber may or may not be equipped with a vacuum pumping system.
[0077] The first chamber (B1) includes a heater and a planar coating system. The planar coating system consists of one set, including a planar magnetron sputtering cathode and two sets of argon gas paths.
[0078] The second chamber (B2) includes a heater and a planar coating system. The planar coating system consists of two sets, each containing a planar magnetron sputtering cathode and two sets of argon gas.
[0079] The vacuum annealing chamber (C) comprises a heater, an argon gas path, and a vacuum pumping system. The vacuum pumping system includes a molecular pump assembly and a roughing pump assembly. The vacuum annealing chamber (C) may include, but is not limited to, a single vacuum annealing chamber, or multiple chambers.
[0080] The nitrogen annealing chamber (D) consists of a heater, an argon gas path, and a vacuum pumping system. The vacuum pumping system includes a molecular pump assembly and a roughing pump assembly. The nitrogen annealing chamber (D) can be, but is not limited to, a single nitrogen annealing chamber, or multiple chambers. When there are multiple nitrogen annealing chambers (D), the number of vacuum pumping systems will also be limited.
[0081] The discharge chamber (E) consists of a gate valve and a vacuum pumping system. The vacuum pumping system consists of a roughing pump assembly.
[0082] It should be noted that the feeding chamber (A), coating chamber (B), vacuum annealing chamber (C), nitrogen annealing chamber (D), and discharge chamber (E) are all conventional preparation equipment in this field, and a brief description of the internal structure of the equipment is sufficient here.
[0083] In this embodiment, the conductive substrate (1) is transferred to the first chamber (B1) as follows: The conductive substrate (1) is placed in the feeding chamber, and then the feeding chamber is evacuated until the pressure in the feeding chamber is 10Pa-50Pa. A buffer chamber and a transition chamber are provided between the feeding chamber and the first chamber. When the specified vacuum state is reached, an appropriate amount of argon gas is introduced into the buffer chamber to achieve vacuum pressure balance with the feeding chamber. After the pressure in the buffer chamber and the feeding chamber is balanced, the conductive substrate (1) is transferred to the buffer chamber, and at this time the heating system in the buffer chamber has reached the specified temperature range. The conductive substrate (1) continues to be transferred in the buffer chamber and undergoes high-temperature preheating. When the vacuum degree of the buffer chamber is evacuated to a high vacuum state by the vacuum system, an appropriate amount of argon gas is introduced again to achieve vacuum pressure balance with the transition chamber. After the pressure in the transition chamber and the buffer chamber is balanced, the conductive substrate (1) is transferred to the transition chamber, and at this time the heating system in the transition chamber has reached the specified temperature range. When the conductive substrate (1) continues to be conveyed to the first chamber, it means that it has entered the next work station.
[0084] It should be noted that during the process of transferring the conductive substrate (1) to the second chamber (B2) and to the vacuum annealing chamber (C) and / or nitrogen annealing chamber (D), the processing steps of the buffer chamber and transition chamber between the first chamber and the second chamber, between the second chamber and the vacuum annealing chamber (C), between the vacuum annealing chamber (C) and the nitrogen annealing chamber (D), and between the nitrogen annealing chamber (D) and the discharge chamber (E) can refer to the processing steps of transferring the conductive substrate (1) to the buffer chamber and transition chamber in the first chamber (B1).
[0085] Furthermore, before the conductive substrate (1) reaches the first chamber, the magnetron sputtering coating equipment is turned on in advance, and the conductive substrate (1) passes through the first chamber (B1) at a stable rate, which means that a first initial hole transport layer is formed on one side surface of the conductive substrate (1); after the first initial hole transport layer is formed, before the conductive substrate (1) is transferred to the second chamber (B2), the magnetron sputtering coating equipment is turned on in advance, and the conductive substrate (1) passes through the second chamber (B2) at a stable rate, which means that a second initial hole transport layer is formed on the side surface of the first initial hole transport layer away from the conductive substrate (1).
[0086] This embodiment provides a method for fabricating a perovskite solar cell, including the method for fabricating a hole transport layer as described in the above embodiment; the conductive substrate (1) includes a substrate (11) and a transparent conductive layer (12) located on one side surface of the substrate (11); after a first hole transport layer (21) is formed on one side surface of the conductive substrate (1), the transparent conductive layer (12) is located between the substrate (11) and the first hole transport layer (21).
[0087] It also includes: forming a perovskite absorption layer (3) on the side of the third hole transport layer (23) away from the conductive substrate (1); forming an electron transport layer (4) on the side of the perovskite absorption layer (3) away from the conductive substrate (1); and forming a metal electrode layer (5) on the side of the electron transport layer (4) away from the conductive substrate (1).
[0088] The hole transport layer (2) formed by combining the first hole transport layer (21), the second hole transport layer (22), and the third hole transport layer (23) using the method of this application can promote the energy level arrangement at the interface between the perovskite absorber layer (3) and the hole transport layer (2), and also enhance the hole extraction efficiency. Secondly, the hole transport layer after two-step magnetron sputtering deposition, vacuum annealing and / or nitrogen annealing improves the quality of the perovskite absorber layer (3) and enhances its crystallinity, increases the grain size, and thus realizes the preparation and production of high-efficiency perovskite solar cells.
[0089] The processes for forming the electron transport layer (4) and the metal electrode layer (5) both include thermal deposition, coating, spin coating, evaporation, or magnetron sputtering. The processes for forming the transparent conductive layer (12), the perovskite absorber layer (3), the electron transport layer (4), and the metal electrode layer (5) are all conventional processes in the field and are not particularly limited, so they will not be described in detail here.
[0090] In one embodiment, the perovskite absorber layer (3) has the general structural formula ABX3, where A is a monovalent cation, B is a divalent cation, and X is a halide anion, wherein A includes, but is not limited to, a methylamino group (MA). + ), formamidin group (FA) + or cesium ions (Cs) + B includes at least one of the following, B including but not limited to Pb 2+ Sn 2+ At least one of them. Specifically, the perovskite absorber layer (3) includes, but is not limited to, Cs. x FA 1-x PBI3 layer, Cs x FA 1-x-y MA y PbI3 layer, MAPbI3 layer, FA yPbI3 layer or CsPbI3 layer.
[0091] In one embodiment, the electron transport layer (4) includes, but is not limited to, one or more of the following: titanium dioxide layer, tin dioxide layer, zinc oxide layer, fullerene layer, and graphene layer.
[0092] In one embodiment, the thickness of the electron transport layer (4) is 10nm-50nm, for example, 10nm, 20nm, 30nm, 40nm or 50nm.
[0093] In one embodiment, the metal electrode layer (5) includes, but is not limited to, one or more of copper, silver and gold layers.
[0094] This embodiment also provides a perovskite solar cell, which is prepared using the perovskite solar cell preparation method described in the above embodiment; it includes: a conductive substrate (1); a first hole transport layer (21) located on one side surface of the conductive substrate (1); a second hole transport layer (22) located on the side of the first hole transport layer (21) away from the conductive substrate (1); and a third hole transport layer (23) located on the side of the second hole transport layer (22) away from the conductive substrate (1); wherein, the conductive substrate (1) includes a substrate (11) and a transparent conductive layer (12) located on one side surface of the substrate (11), and the transparent conductive layer (12) is located between the substrate (11) and the first hole transport layer (21).
[0095] It also includes: a perovskite absorber layer (3) located on the side of the third hole transport layer (23) away from the conductive substrate (1); an electron transport layer (4) located on the side of the perovskite absorber layer (3) away from the conductive substrate (1); and a metal electrode layer (5) located on the side of the electron transport layer (4) away from the conductive substrate (1).
[0096] In one embodiment, the total thickness of the first hole transport layer (21), the second hole transport layer (22), and the third hole transport layer (23) is 10nm-30nm, for example, 10nm, 12nm, 14nm, 16nm, 18nm, 20nm, 22nm, 24nm, 26nm, 28nm, or 30nm.
[0097] Specifically, the thickness of the first hole transport layer (21) is 1nm-8nm, for example, 1nm, 3nm, 5nm, 7nm or 8nm; the thickness of the second hole transport layer (22) is 7nm-18nm, for example, 7nm, 10nm, 12nm, 14nm, 16nm or 18nm; and the thickness of the third hole transport layer (23) is 1nm-5nm, for example, 1nm, 3nm, 12nm or 5nm. Preferably, the thickness of the first hole transport layer (21) is 5nm-8nm, for example, 5nm, 6nm, 7nm, 7.6nm, 7.7nm, 7.8nm or 8nm; the thickness of the second hole transport layer (22) is 10nm-15nm, for example, 10nm, 10.2nm, 11nm, 11.1nm, 12nm, 13nm, 14nm or 15nm; and the thickness of the third hole transport layer (23) is 2nm-4nm, for example, 2nm, 2.5nm, 2.7nm, 2.8nm, 3nm or 4nm.
[0098] Furthermore, the total thickness of the first hole transport layer (21), the second hole transport layer (22), and the third hole transport layer (23) can preferably be set to 20 nm. In this way, even with a low total thickness of the hole transport layer 2, the overall density of the hole transport layer can still be improved by vacuum annealing and / or nitrogen annealing, reducing the number of target numbers required in the preparation of the hole transport layer (2), lowering the production cost of the hole transport layer (2), and improving the production efficiency of the perovskite solar cell; secondly, it can improve the transmittance of sunlight, which is beneficial to improving the photoelectric conversion efficiency of the perovskite solar cell.
[0099] Example 1
[0100] Example 1: The process and parameters for preparing the hole transport layer using the method described in the above examples are as follows:
[0101] A first initial hole transport layer is formed on one side surface of the conductive substrate (1); after the first initial hole transport layer is formed, a second initial hole transport layer is formed on the side surface of the first initial hole transport layer away from the conductive substrate (1); the first initial hole transport layer and the second initial hole transport layer are subjected to vacuum annealing, so that the first initial hole transport layer forms a first hole transport layer (21), and the second initial hole transport layer forms a second hole transport layer (22) and a third hole transport layer (23).
[0102] It should be noted that in Example 1, only vacuum annealing was performed, and nitrogen annealing was not performed.
[0103] In this embodiment, during the vacuum annealing process, the pressure in the vacuum annealing chamber (C) gradually decreases. Specifically, at the start of the vacuum annealing process, the pressure in the vacuum annealing chamber (C) is 10. -2 Pa, at the end of the vacuum annealing process, the pressure in the vacuum annealing chamber (C) is 10. -3 Pa.
[0104] In this embodiment, the vacuum annealing temperature is 300°C and the vacuum annealing time is 600 seconds.
[0105] In this embodiment, during the step of forming a first initial hole transport layer on one side surface of the conductive substrate (1), the power of the radio frequency power supply is 1KW; the temperature of the first chamber is 300℃.
[0106] In the step of forming a second initial hole transport layer on the side of the first initial hole transport layer away from the conductive substrate (1), the power of the radio frequency power supply is 3.5KW; the temperature of the second chamber is 250℃.
[0107] By adjusting the process parameters as described above, the thickness of the first hole transport layer (21) is reduced from 7.9 nm to 7.7 nm, the thickness of the second hole transport layer (22) is reduced from 12.1 nm to 11.1 nm, and the thickness of the third hole transport layer (23) is reduced from 3.1 nm to 2.8 nm. The total thickness of the first hole transport layer (21), the second hole transport layer (22), and the third hole transport layer (23) is reduced from 23.1 nm to 21.6 nm, which means the overall thickness of the hole transport layer is 21.6 nm.
[0108] Example 2
[0109] Example 2 uses the same method as the hole transport layer described in the above examples. The fabrication process and parameters are as follows:
[0110] A first initial hole transport layer is formed on one side surface of the conductive substrate (1); after the first initial hole transport layer is formed, a second initial hole transport layer is formed on the side surface of the first initial hole transport layer away from the conductive substrate (1); the first initial hole transport layer and the second initial hole transport layer are subjected to nitrogen annealing treatment, so that the first initial hole transport layer forms a first hole transport layer (21), the second initial hole transport layer forms a second hole transport layer (22) and a third hole transport layer (23).
[0111] It should be noted that in Example 2, only nitrogen annealing was performed, and vacuum annealing was not performed.
[0112] In this embodiment, during the nitrogen annealing process, the pressure in the nitrogen annealing chamber (D) gradually increases; specifically, at the start of the nitrogen annealing process, the pressure in the nitrogen annealing chamber (D) is 10. -2 At the end of the nitrogen annealing process, the pressure in the nitrogen annealing chamber (D) is 10 Pa. -1 Pa.
[0113] In this embodiment, the nitrogen annealing temperature is 300°C and the nitrogen annealing time is 600 seconds.
[0114] In this embodiment, during the step of forming a first initial hole transport layer on one side surface of the conductive substrate (1), the power of the radio frequency power supply is 1KW; the temperature of the first chamber is 300℃.
[0115] In the step of forming a second initial hole transport layer on the side of the first initial hole transport layer away from the conductive substrate (1), the power of the radio frequency power supply is 3.5KW; the temperature of the second chamber is 250℃.
[0116] By adjusting the process parameters as described above, the thickness of the first hole transport layer (21) is reduced from 7.9 nm to 7.8 nm, the thickness of the second hole transport layer (22) is reduced from 12.1 nm to 11.0 nm, and the thickness of the third hole transport layer (23) is reduced from 3.1 nm to 2.7 nm. The total thickness of the first hole transport layer (21), the second hole transport layer (22), and the third hole transport layer (23) is reduced from 23.1 nm to 21.5 nm, which means the overall thickness of the hole transport layer is 21.5 nm.
[0117] Example 3
[0118] Example 3: The process and parameters for preparing the hole transport layer using the method described in the above examples are as follows:
[0119] A first initial hole transport layer is formed on one side surface of the conductive substrate (1); after forming the first initial hole transport layer, a second initial hole transport layer is formed on the side surface of the first initial hole transport layer away from the conductive substrate (1); the first initial hole transport layer and the second initial hole transport layer are subjected to vacuum annealing, so that the first initial hole transport layer forms a first hole transport layer (21), the second initial hole transport layer forms a second hole transport layer (22) and a third hole transport layer (23), and after vacuum annealing, the first hole transport layer (21), the second hole transport layer (22) and the third hole transport layer (23) are subjected to nitrogen annealing.
[0120] It should be noted that in Example 3, both nitrogen annealing and vacuum annealing were performed.
[0121] In this embodiment, during the vacuum annealing process, the pressure in the vacuum annealing chamber (C) gradually decreases. Specifically, at the start of the vacuum annealing process, the pressure in the vacuum annealing chamber (C) is 10. -2 Pa, at the end of the vacuum annealing process, the pressure in the vacuum annealing chamber (C) is 10. -3 Pa.
[0122] In this embodiment, the vacuum annealing temperature is 300°C and the vacuum annealing time is 600 seconds.
[0123] In this embodiment, during the nitrogen annealing process, the pressure in the nitrogen annealing chamber (D) gradually increases; specifically, at the start of the nitrogen annealing process, the pressure in the nitrogen annealing chamber (D) is 10. -2 At the end of the nitrogen annealing process, the pressure in the nitrogen annealing chamber (D) is 10 Pa. -1 Pa.
[0124] In this embodiment, the nitrogen annealing temperature is 300°C and the nitrogen annealing time is 600 seconds.
[0125] In this embodiment, during the step of forming a first initial hole transport layer on one side surface of the conductive substrate (1), the power of the radio frequency power supply is 1KW; the temperature of the first chamber is 300℃.
[0126] In this embodiment, in the step of forming a second initial hole transport layer on the side surface of the first initial hole transport layer away from the conductive substrate (1), the power of the radio frequency power supply is 3.5KW; the temperature of the second chamber is 250℃.
[0127] By adjusting the process parameters as described above, the thickness of the first hole transport layer (21) is reduced from 7.9 nm to 7.6 nm, the thickness of the second hole transport layer (22) is reduced from 12.1 nm to 10.2 nm, and the thickness of the third hole transport layer (23) is reduced from 3.1 nm to 2.5 nm. The total thickness of the first hole transport layer (21), the second hole transport layer (22), and the third hole transport layer (23) is reduced from 23.1 nm to 20.3 nm, which means the overall thickness of the hole transport layer is 20.3 nm.
[0128] Comparative Example
[0129] A comparative example provides a method for preparing a hole transport layer, comprising: providing a conductive substrate; forming a first hole transport layer on one side surface of the conductive substrate; and forming a second hole transport layer on the side surface of the first hole transport layer away from the conductive substrate.
[0130] It should be noted that the first and second hole transport layers were not subjected to vacuum annealing or nitrogen annealing in the comparative examples.
[0131] In this comparative example, the power of the RF power supply and the chamber temperature corresponding to Examples 1-3 were used to form the first hole transport layer and the second hole transport layer, respectively. The thickness of the first hole transport layer was 7.9 nm, the thickness of the second hole transport layer was 15.2 nm, and the total thickness of the first hole transport layer and the second hole transport layer was 23.1 nm, that is, the overall thickness of the hole transport layer was 23.1 nm.
[0132] The hole transport layers prepared using the methods provided in Examples 1-3 and the comparative examples were subjected to performance testing. The testing methods are as follows:
[0133] Photovoltaic conversion efficiency test: A standard sunlight beam (spectral AM 1.5G, incident power 100mW / cm²) was emitted using a solar simulator. 2 (Temperature 25℃).
[0134] Table 1
[0135]
[0136]
[0137] After testing, the hole transport layer prepared by the hole transport layer preparation method described in Examples 1-3 of this invention was found to be formed by vacuum annealing and / or nitrogen annealing of the first initial hole transport layer and the second initial hole transport layer, so that the first initial hole transport layer forms a first hole transport layer (21), the second initial hole transport layer forms a second hole transport layer (22) and a third hole transport layer (23); the hole transport layer includes the first hole transport layer, the second hole transport layer and the third hole transport layer, and the overall thickness of the hole transport layer is reduced from 23.4 nm to at least 21.6 nm and at most 20.3 nm.
[0138] Specifically, the hole transport layer prepared using the method described in Example 1, wherein vacuum annealing of the first and second initial hole transport layers increases the density of the first hole transport layer by 2.6%, the density of the second hole transport layer by 9.0%, and the density of the third hole transport layer by 10.7%, resulting in an overall increase of 6.9% in the density of the hole transport layer. This increased overall density of the hole transport layer improves the short-circuit current and fill factor of the perovskite solar cell. Specifically, the short-circuit current increases from 22.2A to 22.5A; the fill factor increases from 73.65% to 73.72%; and the photoelectric conversion efficiency increases from 17.08% to 17.25%.
[0139] The hole transport layer prepared using the method described in Example 2, wherein nitrogen annealing treatment is applied to the first initial hole transport layer and the second initial hole transport layer, resulting in a 1.3% increase in the density of the first hole transport layer, a 10.0% increase in the density of the second hole transport layer, a 14.8% increase in the density of the third hole transport layer, and an overall 7.4% increase in the density of the hole transport layer. This increased overall density of the hole transport layer improves the short-circuit current and fill factor of the perovskite solar cell. Specifically, the short-circuit current increases from 22.2A to 22.9A; the fill factor increases from 73.65% to 77.09%; the open-circuit voltage increases from 1.01V to 1.05V; and the photoelectric conversion efficiency increases from 17.08% to 18.58%.
[0140] The hole transport layer prepared using the method described in Example 3 involves vacuum annealing followed by nitrogen annealing of the first and second initial hole transport layers. This results in a 3.9% increase in the density of the first hole transport layer, an 18.6% increase in the density of the second hole transport layer, a 24.0% increase in the density of the third hole transport layer, and an overall 13.8% increase in the density of the hole transport layer. This increased density of the hole transport layer leads to improved short-circuit current and fill factor in the perovskite solar cell. Specifically, the short-circuit current increases from 22.2A to 23.6A; the fill factor increases from 73.65% to 77.82%; the open-circuit voltage increases from 1.01V to 1.06V; and the photoelectric conversion efficiency increases from 17.08% to 19.35%.
[0141] In addition, the hole transport layer prepared by the method of this application has high uniformity, which is beneficial to the preparation of perovskite solar cells and suitable for the production of large-area perovskite solar cells. At the same time, the method of preparing perovskite solar cells provided by this invention is suitable for industrial mass production and is conducive to the stable mass production of perovskite solar cells.
[0142] 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 hole transport layer, characterized in that, The equipment provided includes: a continuously arranged feeding chamber (A), a coating chamber (B), a vacuum annealing chamber (C), a nitrogen annealing chamber (D), and a discharge chamber (E); the coating chamber (B) includes a continuously arranged first chamber (B1) and a second chamber (B2); including: A conductive substrate (1) is provided; the feed chamber (A) is adapted to hold the provided conductive substrate (1); The conductive substrate (1) is transferred to the first chamber (B1) to form a first initial hole transport layer on one side surface of the conductive substrate (1). After the first initial hole transport layer is formed, the conductive substrate (1) is transferred to the second chamber (B2) to form a second initial hole transport layer on the side surface of the first initial hole transport layer away from the conductive substrate (1). After the second initial hole transport layer is formed, the conductive substrate (1) is transferred to a vacuum annealing chamber (C) and / or a nitrogen annealing chamber (D) to perform vacuum annealing and / or nitrogen annealing on the first initial hole transport layer and the second initial hole transport layer, so that the first initial hole transport layer forms a first hole transport layer (21), and the second initial hole transport layer forms a second hole transport layer (22) and a third hole transport layer (23); During the process of transferring the conductive substrate (1) to the first chamber (B1), the second chamber (B2), and the vacuum annealing chamber (C) and / or the nitrogen annealing chamber (D), the conductive substrate (1) is placed in a vacuum environment.
2. The method for preparing a hole transport layer according to claim 1, characterized in that, During the vacuum annealing process, the pressure in the vacuum annealing chamber gradually decreases. When vacuum annealing begins, the pressure should be less than or equal to 10. -1 Pa, when the vacuum annealing process ends, the pressure is less than or equal to 10 Pa. -2 Pa; The vacuum annealing process is performed at a temperature of 200℃-400℃ for 100s-1000s.
3. The method for preparing a hole transport layer according to claim 1, characterized in that, During nitrogen annealing, the pressure in the nitrogen annealing chamber (D) gradually increases. When starting nitrogen annealing, the pressure should be greater than or equal to 10. -3 Pa, when the nitrogen annealing process ends, the pressure is greater than or equal to 10 Pa. -2 Pa; The nitrogen annealing treatment is performed at a temperature of 200℃-400℃ for a duration of 100s-1000s.
4. The method for preparing a hole transport layer according to claim 1, characterized in that, The step of forming a first initial hole transport layer on one side surface of the conductive substrate (1) includes: introducing argon gas into the first chamber; performing magnetron sputtering using a radio frequency power supply; the power of the radio frequency power supply is 1kW-5kW; and the temperature of the first chamber is 200℃-400℃.
5. The method for preparing a hole transport layer according to claim 1, characterized in that, The step of forming a second initial hole transport layer on the side of the first initial hole transport layer away from the conductive substrate (1) includes: introducing argon gas into the second chamber; performing magnetron sputtering using a radio frequency power supply; the power of the radio frequency power supply being 3kW-10kW; and the temperature of the second chamber being 150℃-350℃.
6. The method for preparing the hole transport layer according to claim 4 or 5, characterized in that, Also includes: A heating system is provided for heating the surface of the conductive substrate (1) on the side away from the first initial hole transport layer.
7. The method for preparing a hole transport layer according to claim 1, characterized in that, Before forming a first initial hole transport layer on one side surface of the conductive substrate (1), the conductive substrate (1) is subjected to vacuum preheating treatment. The temperature of the vacuum preheating treatment is 100℃-200℃; the time of the vacuum preheating treatment is 400s-800s.
8. A method for fabricating a perovskite solar cell, characterized in that, include: The method for preparing the hole transport layer according to any one of claims 1-7; The conductive substrate (1) includes a substrate (11) and a transparent conductive layer (12) located on one side surface of the substrate (11); after a first hole transport layer (21) is formed on one side surface of the conductive substrate (1), the transparent conductive layer (12) is located between the substrate (11) and the first hole transport layer (21). It also includes: forming a perovskite absorption layer (3) on the side of the third hole transport layer (23) away from the conductive substrate (1); forming an electron transport layer (4) on the side of the perovskite absorption layer (3) away from the conductive substrate (1); and forming a metal electrode layer (5) on the side of the electron transport layer away from the conductive substrate (1).
9. A perovskite solar cell, characterized in that, The perovskite solar cell is prepared using the method described in claim 8; comprising: a conductive substrate (1); a first hole transport layer (21) located on one side surface of the conductive substrate (1); a second hole transport layer (22) located on the side of the first hole transport layer (21) away from the conductive substrate (1); and a third hole transport layer (23) located on the side of the second hole transport layer (22) away from the conductive substrate (1); wherein the conductive substrate (1) comprises a substrate (11) and a transparent conductive layer (12) located on one side surface of the substrate (11), and the transparent conductive layer (12) is located between the substrate (11) and the first hole transport layer (21); It also includes: a perovskite absorber layer (3) located on the side of the third hole transport layer (23) away from the conductive substrate (1); an electron transport layer (4) located on the side of the perovskite absorber layer (3) away from the conductive substrate (1); and a metal electrode layer (5) located on the side of the electron transport layer (4) away from the conductive substrate (1).
10. The perovskite solar cell according to claim 9, characterized in that, The total thickness of the first hole transport layer (21), the second hole transport layer (22), and the third hole transport layer (23) is 10nm-30nm; the thickness of the first hole transport layer (21) is 1nm-8nm, the thickness of the second hole transport layer (22) is 7nm-18nm, and the thickness of the third hole transport layer (23) is 1nm-5nm.
11. The perovskite solar cell according to claim 9, characterized in that, The first hole transport layer (21) includes a first NiOx layer, the second hole transport layer (22) includes a second NiOx layer, and the third hole transport layer (23) includes a third NiOx layer.