Coating device for preparing perovskite film

Abstract

The utility model belongs to the technical field of perovskite solar energy preparation, and particularly discloses a coating device for preparing a perovskite film, which comprises a coating platform deck, the top of one side of the coating platform deck is a horizontal plane, the other side of the coating platform deck is provided with a liquid accumulation groove, and the horizontal plane and the liquid accumulation groove are sequentially arranged along the X-axis direction of blade coating. A glass substrate is arranged on the horizontal plane, one end of the glass substrate is arranged at the transition joint of the horizontal plane and the liquid accumulation tank, and when the perovskite thin film is prepared, redundant perovskite solution accumulated on the surface of the glass substrate is scraped into the liquid accumulation tank through a scraper; in addition, a cleaning mechanism for cleaning the liquid accumulation tank and a scraper cleaning mechanism for scraping and cleaning the surface of the scraper are further arranged. According to the coating device provided by the utility model, the problem of liquid accumulation at the tail part is effectively solved, so that when a perovskite thin film is prepared, the coating and film forming are uniform and complete, the perovskite coating effect is improved, and the quality of the perovskite thin film is powerfully ensured.

Description

Technical Field

[0001] This invention belongs to the field of perovskite solar energy preparation technology, specifically relating to a coating device for preparing perovskite thin films. Background Technology

[0002] Perovskite solar cells, as a new generation of thin-film solar cells, have achieved photoelectric conversion efficiency very close to that of monocrystalline silicon cells in just over a decade since their introduction in 2009. Compared with traditional silicon-based solar cells, thin-film solar cells have many advantages such as light weight, high flexibility, and simple manufacturing process, and have therefore attracted widespread attention worldwide.

[0003] However, perovskite solar cells still face significant challenges in large-area fabrication, with efficiency losses being a prominent issue. As the fabrication size increases, the conversion efficiency drops significantly. There are two main reasons for this: firstly, ensuring uniformity during large-area deposition of each thin film layer is difficult, negatively impacting cell performance; secondly, laser scribing increases resistance loss and creates dead zones, further reducing cell efficiency.

[0004] Currently, the efficiency of perovskite solar cells is rapidly improving in the laboratory, but this is mostly based on small-area thin-film fabrication. Cells with efficiencies exceeding 20% ​​generally have an area of ​​less than 100 square centimeters. Once the area exceeds 1000 square centimeters, it is difficult to achieve efficiencies above 18%, far from meeting the standards for large-scale commercial applications. For large-area perovskite layer fabrication, slot coating and vapor deposition are mainly used; however, both processes require further refinement. Taking slot coating as an example, the nucleation and crystallization problem of perovskite has not yet been effectively solved. Due to the crystal structure characteristics of perovskite, as the fabrication area increases, if it cannot be completely dried, crystallization will occur, leading to surface gaps or bubbles, affecting the stability of the cell. However, the emergence of air-knife coating head technology has brought hope for solving the key problem of perovskite drying time.

[0005] like Figure 1 As shown, in current methods, perovskite films are applied using a slit-type scalpel. At the starting point on the glass substrate, the scalpel sprays liquid at a certain height above the substrate surface, forming a liquid curtain between the substrate and the scalpel. The scalpel then moves to continuously spray liquid, maintaining the curtain. The liquid's surface tension stretches the film, covering the substrate surface. The film thickness is controlled by the spraying speed. However, due to the low viscosity and dilute nature of the perovskite solution, the solution falls under gravity during coating, causing liquid accumulation in front of the scalpel (which reciprocates along the X and Z axes). When the coating is completed at the tail end of the glass substrate, this accumulated liquid remains, resulting in uneven film thickness and jagged edges, severely impacting product performance.

[0006] Existing technologies reduce film accumulation and areas by adjusting the distance at the coating tail end and controlling the adhesive ejection speed at the coating tail end. However, due to uneven liquid accumulation along the doctor blade's forward direction, this can only reduce the degree and area of ​​liquid accumulation to a certain extent, and cannot completely eliminate liquid accumulation at the tail end. Moreover, uneven liquid accumulation can easily cause film breakage at the tail end, and excessive liquid accumulation can also lead to problems such as dripping from the doctor blade during return and issues with the stage.

[0007] In view of the above, this utility model is hereby proposed. Utility Model Content

[0008] The purpose of this invention is to overcome the shortcomings of the prior art and provide a coating device for preparing perovskite thin films. It is mainly used to solve the problems of uneven film thickness and uneven edges caused by liquid accumulation during the preparation of perovskite thin films in the prior art. At the same time, it avoids various problems such as tail film breakage caused by liquid accumulation and excessive liquid accumulation causing the doctor blade to drip back onto the stage.

[0009] The objective of this utility model is achieved through the following technical solution:

[0010] This utility model provides a coating apparatus for preparing perovskite thin films, including a coating platform, which is a target support platform for the overall operation of the coating apparatus or coating machine, hereinafter referred to as the platform. The top of one side of the platform is set as a horizontal plane, and a liquid accumulation tank is opened on the other side. The horizontal plane and the liquid accumulation tank are arranged sequentially along the X-axis direction of the doctor blade coating. The horizontal plane is used to place a glass substrate. One end of the glass substrate is placed at the transition junction between the horizontal plane and the liquid accumulation tank, so that when preparing the perovskite thin film, the excess perovskite solution (hereinafter referred to as liquid accumulation) accumulated on the surface of the glass substrate is scraped into the liquid accumulation tank by the doctor blade.

[0011] Furthermore, the liquid accumulation tank is configured as a tank structure with a slope, and the slope of the tank structure is arranged on one side of the horizontal plane, so that the excess liquid scraped off by the scraper flows into the liquid accumulation tank along the slope.

[0012] Furthermore, the bottom of the liquid accumulation tank is set as a conical surface or an inclined surface, and a liquid collection pipe is provided at the lowest point of the conical surface or the inclined surface, with the free end of the liquid collection pipe extending into a liquid collection bucket located outside the platform.

[0013] Furthermore, the coating apparatus also includes a cleaning mechanism, which includes a cleaning pipeline. One end of the cleaning pipeline is connected to a container holding a cleaning agent, and the other end has multiple branches. The multiple branches are evenly distributed on the slope of the tank structure, and each branch is equipped with a cleaning nozzle. The cleaning pipeline is equipped with a pressurizing or pressurizing device, which can be a manual pressurizing device or an electric or automatic pressurizing device. Preferably, when the pressurizing or pressurizing device is an electric or automatic pressurizing device, it includes a booster pump and a control switch.

[0014] Furthermore, the coating apparatus also includes a scraper cleaning mechanism for scraping and cleaning the scraper surface. The scraper cleaning mechanism is mounted on the platform via a support plate and is located above the liquid collection tank.

[0015] Furthermore, the scraper cleaning mechanism includes supports fixedly installed at both ends of the support plate, a lead screw rotatably arranged between the two supports, and guide rails fixedly arranged parallel to each other on both sides of the lead screw.

[0016] The lead screw is screwed with a lead screw nut, and both sides of the lead screw nut are sleeved on the guide rail. A cleaning scraper block adapted to the shape of the scraper is detachably installed on the lead screw nut. A drive motor is installed on the support plate, located on the outside of the support. The output shaft of the drive motor is connected to the lead screw through a coupling to drive the cleaning scraper block to move along the Y-axis, thereby cleaning the surface of the scraper.

[0017] Furthermore, the cross-section of the cleaning scraper is a triangular or trapezoidal opening adapted to the scraper blade;

[0018] The triangular or trapezoidal opening is fitted to both sides of the scraper and is 3mm to 5mm away from the tip of the scraper.

[0019] Furthermore, the cleaning scraper is made of polytetrafluoroethylene.

[0020] Furthermore, a distance sensor is installed at the bottom of the triangular or trapezoidal opening, which is used to detect the relative distance between the scraper and the cleaning squeegee.

[0021] Furthermore, the coating device also includes a PLC controller, which is connected to a booster pump, a control switch, a drive motor, and a distance sensor, respectively, and is used to cooperate with the doctor blade of the coating machine to complete the coating operation.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] 1. The coating apparatus provided by this utility model features a horizontal plane for placing a glass substrate and a liquid collection tank for collecting accumulated liquid on a coating platform. The horizontal plane and the liquid collection tank are arranged sequentially along the X-axis direction of the doctor blade coating. This arrangement eliminates the need for the doctor blade to retract on the glass substrate surface during perovskite film preparation; instead, it can retract directly at the liquid collection tank outside the glass substrate. This design not only ensures uniform and full coating of the glass substrate in the coating direction but also scrapes excess perovskite solution (liquid) outside the glass substrate for collection in the liquid collection tank. Furthermore, the liquid collection tank connects to the horizontal plane via a ramp, effectively preventing liquid splashing. Simultaneously, the liquid in the collection tank can be collected in a collection bucket via a collection pipe. Additionally, the coating apparatus of this utility model is specially equipped with a cleaning mechanism for efficient cleaning of the liquid collection tank, ensuring that the tank remains in good working condition and providing strong support for the smooth operation of the entire coating process.

[0024] 2. The coating apparatus provided by this utility model is also equipped with a scraper cleaning mechanism for cleaning the scraper surface. This scraper cleaning mechanism mainly consists of a drive motor, a lead screw, a guide rail, a lead screw nut, and a cleaning scraper block adapted to the shape of the scraper. Under the drive of the drive motor, the cleaning scraper block can reciprocate along the Y-axis. After the scraper is retracted, adjustments are made along the X-axis and Z-axis, and a distance sensor is used for detection to ensure that the scraper stops at the appropriate position on the upper part of the cleaning scraper block (closely fitting it). At this time, the cleaning scraper block moves along the length of the scraper (perpendicular to the X-axis movement direction of the scraper) to scrape the scraper surface, thereby removing excess liquid and preventing residual liquid on the scraper from interfering with the next coating operation, effectively ensuring the quality of the perovskite film.

[0025] 3. The coating device provided by this utility model also includes a PLC controller, which is connected to the booster pump, control switch, drive motor and distance sensor respectively, for coordinated control of the coating device, thereby realizing automated operation and ensuring product consistency. Attached Figure Description

[0026] The accompanying drawings are incorporated in and form part of this specification, and together with the description, serve to explain the principles of this invention.

[0027] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1This is a schematic diagram of an existing coating device;

[0029] Figure 2 This is a schematic diagram of the coating device structure in Embodiment 1 of this utility model;

[0030] Figure 3 This is a top view schematic diagram of the coating device according to Embodiment 1 of this utility model;

[0031] Figure 4 yes Figure 3 Schematic diagram of the sectional structure of the middle AA section;

[0032] Figure 5 This is a schematic diagram of the coating device of Embodiment 1 of this utility model, including the collection pipeline and the collection bucket;

[0033] Figure 6 This is a schematic diagram of the coating device structure in Embodiment 2 of this utility model;

[0034] Figure 7 This is a top view schematic diagram of the coating device according to Embodiment 2 of this utility model;

[0035] Figure 8 These are schematic diagrams of the 7-section BB structure;

[0036] Figure 9 This is a schematic diagram of the scraper cleaning mechanism in the coating device of Embodiment 2 of this utility model.

[0037] in:

[0038] 1 is the coating stage; 11 is the horizontal plane; 12 is the liquid collection tank; 121 is the notch;

[0039] 2 is a scraper;

[0040] 3 is a glass substrate;

[0041] 4 is the liquid collection pipeline;

[0042] 5 is a liquid collection bucket;

[0043] 6 represents the scraper cleaning mechanism; 61 represents the support; 62 represents the lead screw; 63 represents the guide rail; 64 represents the screw...

[0044] 65 is the cleaning scraper; 66 is the drive motor;

[0045] 7 is the support plate. Detailed Implementation

[0046] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numerals in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this invention. Rather, they are merely examples of apparatuses consistent with some aspects of this invention as detailed in the appended claims.

[0047] To enable those skilled in the art to better understand the technical solution of this utility model, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments.

[0048] Example 1

[0049] Please see Figures 2-5 This utility model provides a coating apparatus for preparing perovskite thin films, including a coating stage 1 for use by a coating machine. The top of one side of the coating stage 1 is set as a horizontal plane 11, and a liquid accumulation tank 12 is opened on the other side. The horizontal plane 11 and the liquid accumulation tank 12 are arranged sequentially along the X-axis direction of the coating by the doctor blade 2. The horizontal plane 11 is used to place a glass substrate 3. One end of the glass substrate 3 on the inner side is located at the transition junction between the horizontal plane 11 and the liquid accumulation tank 12. This is used to scrape the excess perovskite solution (liquid) accumulated on the surface of the glass substrate 3 into the liquid accumulation tank 12 by the doctor blade 2 during the preparation of the perovskite thin film.

[0050] Specifically, the appendix provided by this utility model Figure 4 For example, during coating, the doctor blade 2 of the coating machine moves from left to right (along the X-axis). Therefore, a horizontal plane 11 is set on the left side of the coating stage 1, and a liquid accumulation tank 12 is set on the right side. This allows the doctor blade 2 to perform a retraction action on the surface of the glass substrate 3 during the coating and stretching process of the perovskite solution onto the glass substrate 3. The retraction operation is only required at the liquid accumulation tank 12 outside the glass substrate 3. In other words, this invention optimizes the coating process by improving the structure of the coating device. It not only achieves uniform and full coating on the glass substrate 3 in the coating direction, but also scrapes the accumulated liquid outside the glass substrate 3 and collects it with the help of the liquid accumulation tank 12. This effectively solves various problems caused by liquid accumulation and ensures the quality of the perovskite thin film preparation.

[0051] like Figure 5 As shown in this embodiment of the invention, the liquid collection tank 12 is configured as a tank structure with a slope, and the slope of the tank structure is located on one side of the horizontal plane 11. The purpose of this configuration is to allow the excess liquid scraped off by the scraper 2 to flow smoothly into the liquid collection tank 12 along the slope, effectively avoiding splashing caused by the liquid falling directly from a height.

[0052] Preferred, such as Figure 5 As shown in the embodiment of this utility model, the bottom of the liquid accumulation tank 12 is set as a conical surface or an inclined surface, and a liquid collection pipe 4 is provided at the lowest point of the conical surface or the inclined surface. The free end of the liquid collection pipe 4 extends into the liquid collection bucket 5 located outside the coating platform 1. This design can ensure that the liquid flows smoothly to the lowest point and is collected into the liquid collection bucket 5 through the liquid collection pipe 4, thereby realizing efficient collection and centralized treatment of the liquid.

[0053] In addition, the coating device of this utility model also includes a cleaning mechanism (not shown in the figure). The cleaning mechanism includes a cleaning pipeline. One end of the cleaning pipeline is connected to a container containing cleaning agent, and the other end is provided with multiple branches. The multiple branches are evenly distributed on the slope of the tank structure, and each branch is equipped with a cleaning nozzle. The cleaning pipeline is equipped with a pressurizing or pressure-increasing device, which can be a manual pressurizing device or an electric or automatic pressurizing device. When the pressurizing or pressure-increasing device is an electric or automatic pressurizing device, it includes a pressurizing pump and a control switch. Because the waste liquid tank has a slope, that is, the bottom of the tank has an inclination, the waste liquid tank is easily flushed by the solution and flows to the waste liquid bucket. The solution can be pressurized by an anti-corrosion liquid pump (pressurizing pump) or manually by using dry air provided by the factory air handling station to increase the pressure in the solvent bucket, which is used to clean the collection tank 12 at regular intervals to ensure that the collection tank 12 always maintains a good working condition and provides a strong guarantee for the smooth progress of the entire coating process. Of course, other methods can also be used to clean the liquid collection tank 12, as long as the cleaning purpose can be achieved. This utility model does not make any specific limitations.

[0054] Example 2

[0055] Although the technical solution of Embodiment 1 has effectively solved the various problems caused by liquid accumulation, liquid residue remains on the surface of the scraper 2 after each coating operation. If left untreated, this residue may drip onto the glass substrate 3 during the return stroke of the scraper 2, affecting the quality of the perovskite film. Therefore, this embodiment adds a scraper cleaning mechanism 6 to Embodiment 1 to clean the surface of the scraper 2, eliminating the aforementioned effects and further ensuring the quality of the perovskite film.

[0056] Please refer to details. Figures 6-9 In this embodiment of the invention, the scraper cleaning mechanism 6 is mounted on the coating platform 1 via a support plate 7, and the scraper cleaning mechanism 6 is located above the liquid accumulation tank 12. Preferably, to ensure the load-bearing capacity of the support plate 7, a stiffening rib can be added between the support plate 7 and the coating platform 1.

[0057] Specifically, the scraper cleaning mechanism 6 includes supports 61 fixedly installed at both ends of the support plate 7. A lead screw 62 is rotatably mounted between the two supports 61 via bearings, and guide rails 63 are fixedly mounted parallel to both sides of the lead screw 62. The two ends of the guide rails 63 are fixedly connected to the supports 61. A lead screw nut 64 is screwed onto the lead screw 62, and both sides of the lead screw nut 64 are sleeved on the guide rails 63. A cleaning scraper 65 adapted to the shape of the scraper 2 is detachably mounted on the lead screw nut 64 so that the cleaning scraper 65 can be replaced periodically. A drive motor 66 is mounted on the support plate 7, located outside the supports 61. The output shaft of the drive motor 66 is connected to the lead screw 62 via a coupling to drive the cleaning scraper 65 to move along the Y-axis, thereby cleaning the surface of the scraper 2.

[0058] It should be noted that, since the doctor blade 2 of the coating machine can move left and right along the X-axis and up and down along the Z-axis, a distance sensor is installed at the bottom of the cleaning scraper block 65 in this embodiment. When the doctor blade 2 retracts, adjustments are made along the X-axis and Z-axis, and the distance sensor detects the movement to ensure that the doctor blade 2 remains in the appropriate position on the upper part of the cleaning scraper block 65, i.e., both sides of the doctor blade 2 are in close contact with it. At this time, the drive motor 66 is activated, causing the cleaning scraper block 65 to move along the length of the doctor blade 2 to scrape the surface of the doctor blade 2, thereby removing any residual liquid from the surface of the doctor blade 2. This prevents residual liquid on the doctor blade 2 from interfering with the next coating operation, effectively ensuring the quality of the perovskite film.

[0059] In addition, since the scraper cleaning mechanism 6 is located on the upper part of the liquid collection tank 12, in order to avoid the liquid collection tank 12 interfering with the movement of the scraper 2, the length of the groove in the Y-axis direction (front and back direction) of the liquid collection tank 12 should be greater than the length of the scraper 2, and the width of the groove should be greater than the width of the scraper 2. Furthermore, notches 121 are provided on both the front and back sides of the liquid collection tank 12.

[0060] In this embodiment of the invention, the cleaning scraper 65 has a cross-section that is a triangular or trapezoidal opening adapted to the scraper 2. A distance sensor is installed at the bottom of the triangular or trapezoidal opening. The triangular or trapezoidal opening fits against both sides of the scraper 2 and maintains a distance of 3mm to 5mm from the tip of the scraper 2. Furthermore, since the cleaning scraper 65 cleans by friction with the scraper 2, it is made of an elastic material, such as polytetrafluoroethylene (Teflon).

[0061] Preferably, in this embodiment of the present invention, a PLC controller is also included. The PLC controller is connected to the booster pump, the control switch, the drive motor 66 and the distance sensor respectively, and is used to cooperate with the scraper 2 of the coating machine to complete the coating operation, thereby achieving the purpose of automated and efficient operation.

[0062] The above description is merely a specific embodiment of this utility model, enabling those skilled in the art to understand or implement it. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this utility model.

[0063] It should be understood that this utility model is not limited to the content already described above, and various modifications and changes can be made without departing from its scope. The scope of this utility model is limited only by the appended claims.

Claims

1. A coating apparatus for preparing perovskite thin films, characterized in that, The coating includes a coating stage (1), with a horizontal plane (11) on one side and a liquid accumulation tank (12) on the other side. The horizontal plane (11) and the liquid accumulation tank (12) are arranged sequentially along the X-axis direction of the coating by the doctor blade (2). The horizontal plane (11) is used to place a glass substrate (3). One end of the glass substrate (3) is placed at the transition junction between the horizontal plane (11) and the liquid accumulation tank (12). When preparing a perovskite thin film, excess perovskite solution accumulated on the surface of the glass substrate (3) is scraped into the liquid accumulation tank (12) by the doctor blade (2).

2. The coating apparatus for preparing perovskite thin films according to claim 1, characterized in that, The liquid accumulation tank (12) is configured as a tank structure with a slope, and the slope of the tank structure is arranged on one side of the horizontal plane (11) to allow the excess liquid scraped by the scraper (2) to flow into the liquid accumulation tank (12) along the slope.

3. The coating apparatus for preparing perovskite thin films according to claim 2, characterized in that, The bottom of the liquid collection tank (12) is set as a conical surface or an inclined surface, and a liquid collection pipe (4) is provided at the lowest point of the conical surface or the inclined surface. The free end of the liquid collection pipe (4) extends into a liquid collection bucket (5) located outside the coating platform (1).

4. The coating apparatus for preparing perovskite thin films according to claim 2, characterized in that, The coating apparatus further includes a cleaning mechanism, which includes a cleaning pipeline. One end of the cleaning pipeline is connected to a container holding a cleaning agent, and the other end is provided with multiple branches. The multiple branches are evenly distributed on the slope of the tank structure, and each branch is equipped with a cleaning nozzle. The cleaning pipeline is provided with a pressurizing or pressurizing device.

5. The coating apparatus for preparing perovskite thin films according to claim 4, characterized in that, The coating apparatus also includes a scraper cleaning mechanism (6) for scraping and cleaning the surface of the scraper (2). The scraper cleaning mechanism (6) is mounted on the coating platform (1) via a support plate (7) and is located above the liquid collection tank (12). The pressurization or pressure-increasing device includes a pressurization pump and a control switch.

6. The coating apparatus for preparing perovskite thin films according to claim 5, characterized in that, The scraper cleaning mechanism (6) includes supports (61) fixedly installed at both ends of the support plate (7), a lead screw (62) is rotatably arranged between the two supports (61), and guide rails (63) are fixedly arranged parallel to each other on both sides of the lead screw (62). The lead screw (62) is screwed with a lead screw nut (64), and both sides of the lead screw nut (64) are sleeved on the guide rail (63). A cleaning scraper (65) adapted to the shape of the scraper (2) is detachably installed on the lead screw nut (64). A drive motor (66) is installed on the support plate (7) on the outside of the support (61). The output shaft of the drive motor (66) is connected to the lead screw (62) through a coupling to drive the cleaning scraper (65) to move along the Y-axis, thereby cleaning the surface of the scraper (2).

7. The coating apparatus for preparing perovskite thin films according to claim 6, characterized in that, The cross-section of the cleaning scraper (65) is a triangular or trapezoidal opening adapted to the scraper (2); The triangular or trapezoidal opening is fitted to both sides of the scraper (2) and is 3mm to 5mm away from the tip of the scraper (2).

8. The coating apparatus for preparing perovskite thin films according to claim 6, characterized in that, The cleaning scraper (65) is made of polytetrafluoroethylene.

9. The coating apparatus for preparing perovskite thin films according to claim 7, characterized in that, A distance sensor is installed at the bottom of the triangular or trapezoidal opening, and the distance sensor is used to detect the relative distance between the scraper (2) and the cleaning scraper (65).

10. The coating apparatus for preparing perovskite thin films according to claim 9, characterized in that, The coating device also includes a PLC controller, which is connected to a booster pump, a control switch, a drive motor (66) and a distance sensor, respectively, and is used to cooperate with the doctor blade (2) of the coating machine to complete the coating operation.

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