A method for preparing a halo-free droplet-like perovskite film

Abstract

The application relates to the field of perovskite films, in particular to a preparation method of a halo liquid drop-shaped perovskite film, which comprises the following steps: S1: placing a square conductive substrate into a spin coating device of the perovskite film; S2: dropping an excessive lead iodide solution in the middle of the conductive substrate; S3: starting the spin coating device, so that the lead iodide solution in the middle of the conductive substrate is uniformly distributed on the conductive substrate and crystallized into a lead iodide film; closing the spin coating device; S4: dropping an appropriate amount of an ammonium salt solution in the middle of the lead iodide film on the conductive substrate; S5: starting the spin coating device again, so that the ammonium salt solution in the middle of the conductive substrate is uniformly distributed on the lead iodide film, the ammonium salt reacts with the lead iodide film, a perovskite film is formed, and then the spin coating device is closed; and S6: cutting the square perovskite film, so that the perovskite film is in a liquid drop shape; the lead iodide solution and the ammonium salt solution cannot be coated on an operation table and a supporting plate during the spin coating, and the operation table and the supporting plate are prevented from being cleaned.

Description

Technical Field

[0001] This invention relates to the field of perovskite film technology, and in particular to a method for preparing an anti-halo droplet perovskite film. Background Technology

[0002] Perovskite solar cells are a new type of solar cell that uses organometal halide semiconductors to convert solar energy into electrical energy. Compared with traditional crystalline silicon solar cells, perovskite solar cells have higher conversion efficiency, lower cost, and can be made into flexible materials, allowing solar energy to be applied to more scenarios.

[0003] The core structure of perovskite solar cells is the perovskite light-absorbing layer, which is formed by forming a perovskite film on a conductive substrate to absorb solar energy. However, because the stability of perovskite films is easily affected by factors such as temperature and light, they have not yet been mass-produced and are still in the experimental research stage. In the laboratory, perovskite films are prepared by first placing a conductive substrate in a worktable, then dropping a spin-coating solution onto the center of the conductive substrate. The worktable rotates with the conductive substrate, and the spin-coating solution is evenly distributed on the surface of the conductive substrate under centrifugal force, and a perovskite film is formed after crystallization.

[0004] However, in the research, it was necessary to prepare perovskite films of different sizes. But since the operating table was fixed and could not be adjusted, when preparing smaller perovskite films, some of the spin coating solution would leave the conductive substrate and flow onto the operating table as the operating table rotated. After each use, it was necessary to clean it to avoid affecting the preparation of the next perovskite film. When preparing larger perovskite films, only the middle part of the conductive substrate was on the operating table. Since the conductive substrate was a flexible material, the edges of the conductive substrate would tilt slightly downwards due to gravity. This caused the spin coating solution in the middle of the conductive substrate to move towards the edges of the conductive substrate during spin coating, resulting in uneven distribution of the spin coating solution. The formed perovskite film was thin in the middle and thick at the edges, resulting in poor spin coating effect. Summary of the Invention

[0005] Therefore, the technical problem to be solved by the present invention is to overcome the above-mentioned problems in the prior art.

[0006] To solve the above-mentioned technical problems, the present invention provides a method for preparing an anti-halo droplet perovskite film, comprising the following steps:

[0007] S1: Place the square conductive substrate into the spin coating device for the perovskite film;

[0008] S2: Add an excess of lead iodide solution to the center of the conductive substrate;

[0009] S3: Start the spin coating device to evenly distribute the lead iodide solution in the middle of the conductive substrate and crystallize it into a lead iodide film; turn off the spin coating device.

[0010] S4: Drop an appropriate amount of ammonium salt solution into the middle of the lead iodide film on the conductive substrate;

[0011] S5: Restart the spin coating device to evenly distribute the ammonium salt solution in the middle of the conductive substrate onto the lead iodide film, allowing the ammonium salt to react with the lead iodide film to form a perovskite film. Then, turn off the spin coating device.

[0012] S6: Cut the square perovskite film into droplet shapes;

[0013] In one embodiment of the present invention, the spin coating device includes an operating table; the operating table has a first cavity; a plurality of telescopic rods are provided on the operating table; the plurality of telescopic rods are arranged in a circumferential array on the upper end of the operating table; a rack is fixedly connected to one side of each telescopic rod; one end of the telescopic rod and the rack is located in the first cavity, and the telescopic rod and the rack are located on the outside of the operating table; a plurality of first sliding grooves are provided on the side wall of the operating table to slidably connect with the telescopic rods and the racks; the first sliding grooves are located at the upper end of the side wall of the operating table; an internal gear ring is slidably connected in the lower end of the first cavity; a plurality of gears are provided in the first cavity, and the gears correspond one-to-one with the racks; the lower end of each gear meshes with the internal gear ring, and the upper end of each gear meshes with the corresponding rack; a first motor is fixedly connected to the lower part of the operating table; the output end of the first motor passes through the bottom of the operating table and is fixedly connected to one of the gears; a support plate is fixedly connected to the end of each telescopic rod away from the operating table.

[0014] In one embodiment of the present invention, a limiting ring is fixedly connected inside the first cavity; the limiting ring is provided with a plurality of second sliding grooves that are slidably connected to the telescopic rod and the rack; the second sliding grooves are located at the upper end of the limiting ring;

[0015] In one embodiment of the present invention, a control console is provided below the operating table; a support rod is fixedly connected above the control console; a second cavity is provided inside the support rod; a second motor is fixedly connected inside the second cavity; the output end of the second motor passes through the top of the support rod and is fixedly connected to the middle of the operating table; the top of the support rod is rotatably connected to the bottom of the operating table; the first motor is located outside the support rod.

[0016] In one embodiment of the present invention, a plurality of first negative pressure holes are provided on the top of the operating table; and an air pump is connected to the bottom of the operating table.

[0017] In one embodiment of the present invention, the top of the support plate is provided with a plurality of second negative pressure holes; the support plate is provided with a third cavity; the telescopic rod is provided with a fourth cavity; the third cavity, the fourth cavity and the first cavity are connected.

[0018] In one embodiment of the present invention, a support ring is provided between the operating table and the control console; the lower end of the support ring is fixedly connected to the control console, and the upper end of the support ring is slidably connected to the operating table; the support rod and the first motor are located inside the support ring;

[0019] In one embodiment of the present invention, an annular collector is fixedly connected to the outer wall of the support ring; the annular collector is used to collect the spin-coated solution flowing out from the edge of the conductive substrate;

[0020] In one embodiment of the present invention, the annular collector is provided with a groove; the groove is provided with a discharge port;

[0021] In one embodiment of the present invention, a liquid collection tank is connected to the control console; the liquid collection tank is located below the discharge port;

[0022] The technical solution of the present invention has the following advantages compared with the prior art:

[0023] 1. In order to support the conductive substrates during spin coating of square conductive substrates of different sizes, the present invention ensures that the support plates and operating table can support the conductive substrates while preventing lead iodide solution and ammonium salt solution from being applied to the operating table and support plates during spin coating, thus avoiding cleaning of the operating table and support plates; by starting a first motor; the output end of the first motor drives one of the gears to rotate. Since the lower end of the gear meshes with the internal gear ring, the rotation of the gear drives the internal gear ring to rotate, and the internal gear ring drives the other gears to rotate together; so that all the gears rotate simultaneously. Since the upper end of the gear meshes with the corresponding rack, the gears... The rack and telescopic rod move within a groove on the side wall of the operating table. The groove restricts the movement direction of the telescopic rod and rack, allowing several telescopic rods to shorten or extend simultaneously. Adjusting the distance between the support plate and the operating table aligns the end of the support plate away from the operating table with the edge of the square conductive substrate. This allows each support plate and the operating table to support the center and edge of the conductive substrate respectively when spin-coating conductive substrates of different sizes, resulting in better spin-coating effect. At the same time, it prevents lead iodide solution and ammonium salt solution from being applied to the operating table and support plate during spin-coating, avoiding the need for cleaning the operating table and support plate.

[0024] 2. In order to fix the conductive substrate on the operating table, the present invention involves placing the conductive substrate in a suitable position on the operating table, then activating a vacuum pump via the control panel. The vacuum pump removes air from the first cavity, creating a negative pressure within the first cavity. The center of the conductive substrate is then negatively pressed against the operating table through the first negative pressure hole. This fixes the conductive substrate firmly on the operating table, preventing slowdown or deviation in rotation due to friction between the conductive substrate and the operating table. To prevent the edges of the flexible conductive substrate from moving during rotation, the vacuum pump is activated via the control panel, removing air from the first cavity and creating a negative pressure within it. Since the third and fourth cavities are connected to the first cavity, negative pressure is also created in the third and second cavities. The edges of the conductive substrate are then negatively pressed against the support plate through the second negative pressure hole, further preventing movement of the edges of the flexible conductive substrate during rotation. Attached Figure Description

[0025] To make the content of this invention easier to understand, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0026] Figure 1 This is a schematic diagram of the main structure of one embodiment of the present invention;

[0027] Figure 2 This is a partial structural diagram of one embodiment of the present invention. Figure 1 ;

[0028] Figure 3 This is a partial structural cross-sectional view of one embodiment of the present invention;

[0029] Figure 4 This is a schematic diagram of a telescopic rod structure according to an embodiment of the present invention;

[0030] Figure 5 This is a schematic diagram of the internal structure of the operating console according to an embodiment of the present invention;

[0031] Figure 6 This is a partial structural diagram of one embodiment of the present invention. Figure 2 ;

[0032] Figure 7 This is a schematic diagram of a support ring structure according to an embodiment of the present invention;

[0033] Figure 8 This is a schematic diagram of a ring collector structure according to an embodiment of the present invention;

[0034] Figure 9 This is a schematic diagram of the liquid collection tank structure according to an embodiment of the present invention.

[0035] Explanation of reference numerals on the accompanying drawings:

[0036] 1. Operating platform; 2. Telescopic rod; 3. Rack; 4. Internal gear ring; 5. Gear; 6. First motor; 7. Support plate; 8. Limiting ring; 9. Control console; 10. Support rod; 11. Second motor; 12. First negative pressure hole; 13. Air pump; 14. Second negative pressure hole; 15. Support ring; 16. Annular collector; 17. Discharge port; 18. Liquid collection tank. Detailed Implementation

[0037] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments described are not intended to limit the present invention.

[0038] A method for preparing an anti-halo droplet-shaped perovskite film includes the following steps:

[0039] S1: Place the square conductive substrate into the spin coating device for the perovskite film;

[0040] S2: Add an excess of lead iodide solution to the center of the conductive substrate;

[0041] S3: Start the spin coating device to evenly distribute the lead iodide solution in the middle of the conductive substrate and crystallize it into a lead iodide film; turn off the spin coating device.

[0042] S4: Drop an appropriate amount of ammonium salt solution into the middle of the lead iodide film on the conductive substrate;

[0043] S5: Restart the spin coating device to evenly distribute the ammonium salt solution in the middle of the conductive substrate onto the lead iodide film, allowing the ammonium salt to react with the lead iodide film to form a perovskite film. Then, turn off the spin coating device.

[0044] S6: Cut the square perovskite film into droplet shapes;

[0045] One embodiment of the present invention, referring to Figures 4-6As shown, the spin coating device includes an operating table 1; the operating table 1 has a first cavity; a plurality of telescopic rods 2 are arranged on the operating table 1; the plurality of telescopic rods 2 are arranged in a circumferential array on the upper end of the operating table 1; a rack 3 is fixedly connected to one side of each telescopic rod 2; one end of each telescopic rod 2 and rack 3 is located in the first cavity, and the telescopic rod 2 and rack 3 are located on the outside of the operating table 1; a plurality of first sliding grooves are formed on the side wall of the operating table 1 to slidably connect with the telescopic rods 2 and rack 3; the first sliding grooves are located in The upper side wall of the operating table 1 has an internal gear ring 4 slidably connected to the lower end of the first cavity; a plurality of gears 5 are arranged in the first cavity, and each gear 5 corresponds to a rack 3; the lower end of each gear 5 meshes with the internal gear ring 4, and the upper end of each gear 5 meshes with the corresponding rack 3; a first motor 6 is fixedly connected to the lower part of the operating table 1; the output end of the first motor 6 passes through the bottom of the operating table 1 and is fixedly connected to one of the gears 5; a support plate 7 is fixedly connected to the end of the telescopic rod 2 away from the operating table 1.

[0046] To ensure that the support plates 7 and the operating table 1 can support the conductive substrates during spin coating of square conductive substrates of different sizes, and to prevent lead iodide solution and ammonium salt solution from being applied to the operating table 1 and support plates 7 during spin coating, thus avoiding cleaning of the operating table 1 and support plates 7, the first motor 6 is started. The output of the first motor 6 drives one of the gears 5 to rotate. Since the lower end of the gear 5 meshes with the internal gear ring 4, the rotation of the gear 5 drives the internal gear ring 4 to rotate, and the internal gear ring 4 drives the other gears 5 to rotate together, so that all the gears 5 rotate simultaneously. Since the upper end of the gear 5 meshes with the corresponding rack 3, the gear 5 carries... The movable rack 3 and the telescopic rod 2 move within the groove on the side wall of the operating table 1. The groove restricts the movement direction of the telescopic rod 2 and the rack 3, allowing several telescopic rods 2 to shorten or extend simultaneously. The distance between the support plate 7 and the operating table 1 is adjusted so that the end of the support plate 7 away from the operating table 2 is aligned with the edge of the square conductive substrate. This allows each support plate 7 and the operating table 1 to support the middle and edge of the conductive substrate respectively when spin-coating conductive substrates of different sizes, resulting in better spin-coating effect. At the same time, it prevents lead iodide solution and ammonium salt solution from being applied to the operating table 1 and the support plate 7 during spin-coating, avoiding the need for cleaning the operating table 1 and the support plate 7.

[0047] Reference Figure 5 As shown, a limiting ring 8 is fixedly connected inside the first cavity; the limiting ring 8 has several second sliding grooves that are slidably connected to the telescopic rod 2 and the rack 3; the second sliding grooves are located at the upper end of the limiting ring 8;

[0048] The sliding direction of the telescopic rod 2 and the rack 3 is limited by the second sliding groove on the limiting ring 8 and the first sliding groove on the operating table 1;

[0049] Reference Figure 1 , Figure 3 and Figure 6 As shown, a control console 9 is provided below the control panel 1; a support rod 10 is fixedly connected above the control console 9; a second cavity is provided inside the support rod 10; a second motor 11 is fixedly connected inside the second cavity; the output end of the second motor 11 passes through the top of the support rod 10 and is fixedly connected to the middle of the control panel 1; the top of the support rod 10 is rotatably connected to the bottom of the control panel 1; the first motor 6 is located on the outside of the support rod 10.

[0050] To spin-coat the solution dropped onto the conductive substrate, the rotation speed and rotation time of the second motor 11 are controlled by the control console 9. The control console 9 starts the second motor 11, and the output of the second motor 11 drives the operating table 1 to rotate, causing the conductive substrate on the operating table 1 to rotate with the operating table 1. The solution on the conductive substrate is subjected to centrifugal force and moves to the periphery of the conductive substrate, eventually spreading the solution evenly on the conductive substrate. The support rod 10 supports the operating table and reduces the pressure on the second motor 11.

[0051] Reference Figure 1 , Figure 2 , Figure 3 and Figure 6 As shown, the top of the operating table 1 is provided with several first negative pressure holes 12; the bottom of the operating table 1 is connected to an air pump 13.

[0052] In order to fix the conductive substrate on the operating table 1, after placing the conductive substrate in a suitable position on the operating table 1, the air pump 13 is started through the control console 9. The air pump 13 removes the air in the first cavity, creating a negative pressure in the first cavity; then the middle part of the conductive substrate is negatively pressed onto the operating table 1 through the first negative pressure hole 12; thus fixing the conductive substrate on the operating table 1, and preventing the rotation speed from slowing down or deviating due to the friction between the conductive substrate and the operating table 1.

[0053] Reference Figures 1-5 As shown, the top of the support plate 7 is provided with a plurality of second negative pressure holes 14; the support plate 7 is provided with a third cavity; the telescopic rod 2 is provided with a fourth cavity; the third cavity, the fourth cavity and the first cavity are connected.

[0054] To prevent the edge of the flexible conductive substrate from moving during rotation, the air pump 13 is activated via the control console 9. The air pump 13 removes the air from the first cavity, creating a negative pressure inside the first cavity. Since the third cavity, the fourth cavity, and the first cavity are connected, negative pressure is also created in the third cavity and the second cavity. The edge of the conductive substrate is then pressed against the support plate 7 through the second negative pressure hole 14, thus preventing the edge of the flexible conductive substrate from moving during rotation.

[0055] Reference Figure 7 As shown, a support ring 15 is provided between the operating table 1 and the control console 9; the lower end of the support ring 15 is fixedly connected to the control console 9, and the upper end of the support ring 15 is slidably connected to the operating table 1; the support rod 10 and the first motor 6 are located inside the support ring 15.

[0056] The support ring 15 protects the first motor 6 from contact with the iodine ions in the spin coating solution, reduces the corrosion of the external metal of the first motor 6 by iodine ions, and supports the operating table 1 at the same time.

[0057] Reference Figures 1-3 , Figure 8 and Figure 9 As shown, an annular collector 16 is fixedly connected to the outer wall of the support ring 15; the annular collector 16 is used to collect the spin-coated solution flowing out from the edge of the conductive substrate; the annular collector 16 is provided with a groove; the groove is provided with a discharge port 17; a liquid collection tank 18 is contacted and connected to the control console 9; the liquid collection tank 18 is located below the discharge port 17.

[0058] To collect excess spin coating solution, when the conductive substrate is rotated, the excess spin coating solution is ejected away from the operating table 1, blocked by the side wall of the annular collector 16, and flows along the side wall into the groove of the annular collector 16, and then enters the collection tank 18 through the outlet 17; the lead iodide solution and ammonium salt solution are collected through two different collection tanks 18 respectively, saving spin coating solution and allowing it to be reused.

[0059] Working principle:

[0060] By starting the first motor 6, the output of the first motor 6 drives one of the gears 5 to rotate. Since the lower end of the gear 5 meshes with the internal gear ring 4, the rotation of the gear 5 drives the internal gear ring 4 to rotate, and the internal gear ring 4 drives the other gears 5 to rotate together. This causes all the gears 5 to rotate simultaneously. Since the upper end of the gear 5 meshes with the corresponding rack 3, the gear 5 drives the rack 3 and the telescopic rod 2 to move in the groove on the side wall of the operating table 1. The groove restricts the movement direction of the telescopic rod 2 and the rack 3, allowing several telescopic rods 2 to shorten or extend simultaneously. Adjusting the distance between the support plate 7 and the operating table 1 aligns the end of the support plate 7 away from the operating table 2 with the edge of the square conductive substrate. This allows each support plate 7 and the operating table 1 to support the middle and edge of the conductive substrate respectively when spin-coating conductive substrates of different sizes, resulting in a better spin-coating effect. At the same time, it prevents the lead iodide solution and ammonium salt solution from being applied to the operating table during spin-coating. To avoid cleaning the operating table 1 and support plate 7, the air pump 13 is started through the control console 9. The air pump 13 removes the air from the first cavity, creating a negative pressure in the first cavity. Since the third cavity, fourth cavity and first cavity are connected, negative pressure is also created in the third cavity and second cavity. The middle and edge of the conductive substrate are then negatively pressed onto the operating table 1 and support plate 7 through the first negative pressure hole 12 and the second negative pressure hole 14, respectively, so that the middle and edge of the soft conductive substrate will not move during rotation. By setting up the annular collector 16, when the conductive substrate rotates, the excess spin coating solution is sprayed away from the operating table 1, blocked by the side wall of the annular collector 16, and flows into the groove of the annular collector 16 along the side wall, and then enters the collection tank 18 through the discharge port 17. The lead iodide solution and ammonium salt solution are collected through two different collection tanks 18, saving spin coating solution and allowing it to be reused.

[0061] 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 an anti-halo droplet-shaped perovskite film, characterized in that: Includes the following steps: S1: Place the square conductive substrate into the spin coating device for the perovskite film; S2: Add an excess of lead iodide solution to the center of the conductive substrate; S3: Start the spin coating device to evenly distribute the lead iodide solution in the middle of the conductive substrate and crystallize it into a lead iodide film; turn off the spin coating device. S4: Drop an appropriate amount of ammonium salt solution into the middle of the lead iodide film on the conductive substrate; S5: Restart the spin coating device to evenly distribute the ammonium salt solution in the middle of the conductive substrate onto the lead iodide film, allowing the ammonium salt to react with the lead iodide film to form a perovskite film. Then, turn off the spin coating device. S6: Cut the square perovskite film into droplet shapes; The spin coating device includes an operating table (1); the operating table (1) has a first cavity; several telescopic rods (2) are provided on the operating table (1); the several telescopic rods (2) are arranged in a circumferential array on the upper end of the operating table (1); a rack (3) is fixedly connected to one side of each telescopic rod (2); one end of each telescopic rod (2) and rack (3) is located in the first cavity, and the telescopic rod (2) and rack (3) are located on the outside of the operating table (1); several first sliding grooves are provided on the side wall of the operating table (1) to slide and connect with the telescopic rods (2) and racks (3); the first sliding grooves are located on the operating table (1)... The upper end of the side wall of the platform (1); an internal gear ring (4) is slidably connected in the lower end of the first cavity; a number of gears (5) are provided in the first cavity, and the gears (5) correspond one-to-one with the racks (3); the lower end of the gears (5) meshes with the internal gear ring (4), and the upper end of the gears (5) meshes with the corresponding racks (3); a first motor (6) is fixedly connected to the lower part of the operating platform (1); the output end of the first motor (6) passes through the bottom of the operating platform (1) and is fixedly connected to one of the gears (5); a support plate (7) is fixedly connected to the end of the telescopic rod (2) away from the operating platform (1).

2. The method for preparing an anti-halo droplet perovskite film according to claim 1, characterized in that: A limiting ring (8) is fixedly connected inside the first cavity; the limiting ring (8) has several second sliding grooves that are slidably connected to the telescopic rod (2) and the rack (3); the second sliding grooves are located at the upper end of the limiting ring (8).

3. The method for preparing an anti-halo droplet-shaped perovskite film according to claim 2, characterized in that: A control console (9) is provided below the operating table (1); a support rod (10) is fixedly connected above the control console (9); a second cavity is provided inside the support rod (10); a second motor (11) is fixedly connected inside the second cavity; the output end of the second motor (11) passes through the top of the support rod (10) and is fixedly connected to the middle of the operating table (1); the top of the support rod (10) is rotatably connected to the bottom of the operating table (1); the first motor (6) is located outside the support rod (10).

4. The method for preparing an anti-halo droplet perovskite film according to claim 3, characterized in that: The top of the operating table (1) is provided with several first negative pressure holes (12); the bottom of the operating table (1) is connected to a vacuum pump (13).

5. The method for preparing an anti-halo droplet perovskite film according to claim 4, characterized in that: The top of the support plate (7) is provided with several second negative pressure holes (14); the support plate (7) is provided with a third cavity; the telescopic rod (2) is provided with a fourth cavity; the third cavity, the fourth cavity and the first cavity are connected.

6. The method for preparing an anti-halo droplet perovskite film according to claim 5, characterized in that: A support ring (15) is provided between the operating table (1) and the control console (9); the lower end of the support ring (15) is fixedly connected to the control console (9), and the upper end of the support ring (15) is slidably connected to the operating table (1); the support rod (10) and the first motor (6) are located inside the support ring (15).

7. The method for preparing an anti-halo droplet perovskite film according to claim 6, characterized in that: An annular collector (16) is fixedly connected to the outer wall of the support ring (15); the annular collector (16) is used to collect the spin-coated solution flowing out from the edge of the conductive substrate.

8. The method for preparing an anti-halo droplet perovskite film according to claim 7, characterized in that: The annular collector (16) has a groove; the groove has a discharge port (17).

9. The method for preparing an anti-halo droplet perovskite film according to claim 8, characterized in that: The control console (9) is connected to a liquid collection tank (18); the liquid collection tank (18) is located below the discharge port (17).

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