Perovskite thin film preparation device and perovskite thin film preparation method

Abstract

The application discloses a preparation device of perovskite film and a preparation method of perovskite film, and relates to the technical field of solar cells. The substrate is transported by a transmission mechanism, when the substrate is transported to a photoelectric induction mechanism, a precursor solution is injected into a slit coating mechanism by an external injection system, the substrate is once hard coated by the slit coating mechanism, and then is twice coated by a secondary soft film coating mechanism to form a uniform perovskite wet film; the substrate is transported by the transmission mechanism to pass through a blowing and drying assembly to blow and dry the perovskite wet film, and the perovskite film is formed. The preparation device of perovskite film can realize one-step solution method and two-step solution method for preparing the film, the secondary soft coating process can reduce or eliminate hard damage of the film, and the film forming quality is improved; automatic control and continuous transmission are beneficial to realizing continuous large-area and large-scale production of the solution method, improving production efficiency and reducing production cost.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of solar cells, in particular to a preparation device of perovskite thin film and a preparation method of perovskite thin film. BACKGROUND

[0002] Perovskite solar cells are attracting much attention due to their high theoretical efficiency and solution processability. Currently, the common preparation methods of perovskite thin film include spin coating, doctor blading, slot-die coating, spray coating and vapor assisted deposition.

[0003] The currently reported high-efficiency devices usually use spin coating method, and the effective area of the cell is usually less than 0.1 cm 2 . Moreover, toxic anti-solvents such as chlorobenzene are used to extract organic solvents from perovskite precursor solution during the preparation process. The above two points cannot meet the requirements of industrial production on the one hand, and the use of anti-solvents will have adverse effects on the environment and human body on the other hand. Although the vapor assisted deposition technology can realize large-area preparation and no anti-solvent participation, it involves vacuum equipment, which is costly and has low material utilization.

[0004] The common solution method for large-area perovskite preparation technology includes doctor blading and slot-die coating. The doctor blading method needs to continuously supplement the precursor liquid during the preparation process, which cannot realize continuous coating production, thereby increasing the labor cost and time cost. Moreover, the liquid supplementing process is prone to cause the problems of non-timely supplementing and non-uniform thin film at the supplementing connection. The slot-die coating method solves the problem of continuous liquid supplementing and can more finely control the coating process. However, the existing technology still cannot avoid the use of anti-solvents, and the anti-solvents cannot be removed in time, which will cause damage to the perovskite thin film. Moreover, the use of anti-solvents such as chlorobenzene will have adverse effects on human health and the environment.

[0005] Therefore, there are still certain technical difficulties in the large-area, efficient and high-quality preparation of perovskite thin film.

[0006] In view of this, the present application is proposed. SUMMARY

[0007] The present application aims to provide a preparation device of perovskite thin film and a preparation method of perovskite thin film, so as to realize the large-area, efficient and high-quality preparation of perovskite thin film.

[0008] The present application is realized in the following manner:

[0009] In a first aspect, the present application provides a preparation device of perovskite thin film, which comprises a transmission mechanism for transmitting a substrate, a photoelectric induction mechanism for sensing the position of the substrate, a coating mechanism for coating the surface of the substrate to form a perovskite wet film, and a blowing and drying assembly for post-treatment of the perovskite wet film formed after coating.

[0010] The coating mechanism and the blowing and drying assembly are sequentially arranged in the conveying direction of the conveying mechanism, so that the substrate is conveyed by the conveying mechanism to sequentially pass through the coating mechanism and the blowing and drying assembly;

[0011] The coating mechanism comprises a slit coating mechanism and a secondary soft film coating mechanism sequentially arranged in the conveying direction, and the installation position of the photoelectric sensing mechanism corresponds to the slit coating mechanism. The photoelectric sensing mechanism is connected to an external liquid injection system, so that the slit coating mechanism is injected with liquid by the external liquid injection system when the substrate is conveyed to the photoelectric sensing mechanism.

[0012] In an optional embodiment of the present application, the slit coating mechanism comprises a first slit die and a second slit die fixedly arranged opposite to the first slit die. The first slit die is provided with at least one feed port for connecting to the external liquid injection system. The first slit die and the second slit die are internally formed with a liquid storage cavity in communication with the feed port. The bottom of the liquid storage cavity is communicated with a straight-through slit extending from the liquid storage cavity to the bottom of the slit coating mechanism, and the straight-through slit extends from one end of the slit coating mechanism in the horizontal direction to the opposite end, so as to output the coating liquid onto the substrate through the straight-through slit.

[0013] In an optional embodiment of the present application, the secondary soft film coating mechanism comprises a front clamping plate, a rear clamping plate, and a fixing member for fixing the front clamping plate and the rear clamping plate. The soft film is clamped in the front clamping plate and the rear clamping plate, and extends towards the conveying mechanism, so as to perform secondary coating on the material coated on the substrate.

[0014] In an optional embodiment of the present application, the blowing and drying assembly comprises a wind knife blowing mechanism and a post-processing mechanism sequentially arranged in the conveying direction. The post-processing mechanism comprises a top processing unit and a bottom heating unit. The bottom heating unit is installed on the conveying mechanism to heat from the bottom of the substrate. The top processing unit is arranged opposite to the bottom heating unit, and is a heating and negative pressure integrated device, so as to simultaneously heat and / or perform negative pressure air extraction on the perovskite wet film after the substrate is conveyed below the top processing unit.

[0015] In an optional embodiment of the present application, a fixing support is arranged on the conveying mechanism, and a mounting cross beam is connected to the fixing support. The slit coating mechanism is installed on the mounting cross beam by a first screw rod adjusting mechanism, so as to adjust the height of the slit coating mechanism by the first screw rod adjusting mechanism.

[0016] A first cross beam suspension arm is further fixed on the mounting cross beam. The secondary soft film coating mechanism is installed on the first cross beam suspension arm by a second screw rod adjusting mechanism, so as to adjust the contact angle and pressure of the secondary soft film coating mechanism on the perovskite wet film by the second screw rod adjusting mechanism.

[0017] In the alternative embodiment of the present application, a second crossbeam suspension arm and a third crossbeam suspension arm are further included, the first crossbeam suspension arm is connected with the second crossbeam suspension arm through a first universal ball joint, the second crossbeam suspension arm and the third crossbeam suspension arm are connected through a second universal ball joint, and an end of the third crossbeam suspension arm away from the second crossbeam suspension arm is connected with the air knife blowing mechanism.

[0018] In the alternative embodiment of the present application, the air knife blowing mechanism comprises a first blowing die and a second blowing die fixedly installed opposite to the first blowing die, at least one connecting port for connecting the air supply system is arranged on the first blowing die, an air supply chamber is formed in the inner cavities of the first blowing die and the second blowing die, and the first blowing die and the second blowing die are spaced apart at the bottom to form a linear slit air outlet communicating with the air supply chamber.

[0019] The air supply chamber comprises a main body chamber and a connecting channel for connecting the main body chamber and the linear slit air outlet, the width of the main body chamber is greater than the width of the linear slit air outlet, and the width of the connecting channel gradually decreases from the top to the bottom.

[0020] In the alternative embodiment of the present application, the conveying mechanism comprises a first conveying mechanism and a second conveying mechanism for receiving the output material of the first conveying mechanism, the coating mechanism and the air knife blowing mechanism are installed above the first conveying mechanism, the bottom heating unit in the post-processing mechanism is installed on the second conveying mechanism, and a pre-heating mechanism is further arranged on the first conveying mechanism.

[0021] In the second aspect, the present application further provides a preparation method of the perovskite film, which is prepared by using the preparation device of the perovskite film in any of the above-mentioned embodiments, and comprises the following steps:

[0022] The substrate is conveyed by the conveying mechanism, the precursor solution is injected into the slit coating mechanism by using the external injection system when the substrate is conveyed to the photoelectric induction mechanism, the substrate is once hard coated by the slit coating mechanism, and then is twice coated by the secondary soft film coating mechanism to form a uniform perovskite wet film.

[0023] The substrate conveyed by the conveying mechanism passes through the blowing and drying assembly to blow and dry the perovskite wet film, thereby forming the perovskite film.

[0024] In the alternative embodiment of the present application, the preparation method has at least one of the following features a1-a13:

[0025] Feature a1: the distance between the DC slit bottom of the slit coating mechanism and the substrate is 0 cm-5 cm;

[0026] Feature a2: the liquid outflow rate of the slit coating mechanism is 0.001 mL / min-20 mL / min;

[0027] Feature a3: the width of the linear slit on the slit coating mechanism is 0.1 μm to 500 μm;

[0028] Feature a4: the contact angle between the soft film on the secondary soft film coating mechanism and the substrate is 0° to 90°;

[0029] Feature a5: the distance between the lowest point of the air knife blowing mechanism and the substrate is 0 cm to 10 cm;

[0030] Feature a6: the width of the linear slit air outlet on the air knife blowing mechanism is 0.1 μm to 500 μm;

[0031] Feature a7: the pressure of the linear slit air outlet on the air knife blowing mechanism is 0 MPa to 1 MPa;

[0032] Feature a8: the heating temperature of the preheating mechanism is 20℃ to 200℃;

[0033] Feature a9: the transmission rate of the transmission mechanism is 0 mm / s to 100 mm / s;

[0034] Feature a10: the heating range of the bottom heating unit on the post-processing mechanism is 20℃ to 500℃;

[0035] Feature a11: the heating range of the top processing unit on the post-processing mechanism is 20℃ to 500℃;

[0036] Feature a12: the negative pressure air speed of the top processing unit on the post-processing mechanism is 0 m / s to 12 m / s;

[0037] Feature a13: the preparation method is to prepare a perovskite film by one-step solution method or two-step solution method;

[0038] When the one-step solution method is used to prepare the perovskite film, the solute of the precursor solution used is at least one of one or more of ABX3, wherein A is at least one of a monovalent organic cation and a metal ion, B is a metal ion, and X is at least one halogen element;

[0039] The steps of preparing the perovskite film by the two-step solution method include: first, using a first perovskite precursor solution to coat, and after passing through the blowing and drying assembly, a substrate with metal halide attached is formed; then, using a second perovskite precursor solution to coat on the substrate with metal halide attached, and after passing through the blowing and drying assembly, a perovskite film is formed;

[0040] The solute in the first perovskite precursor solution is at least one of BX2, and the solute in the second perovskite precursor solution is at least one of AX, wherein A is at least one of monovalent organic cation and metal ion, B is a metal ion, and X is at least one halogen element.

[0041] The solvents used to prepare the precursor solution, the first perovskite precursor solution, and the second perovskite precursor solution are all selected from at least one of isopropanol, methoxyethanol, dimethylformamide, dimethyl sulfoxide, N,N-dimethylacetamide, and N-methylpyrrolidone.

[0042] This invention offers the following advantages: A transport mechanism is used to transport the substrate. When the substrate reaches the photoelectric sensing mechanism, an external liquid injection system injects a precursor solution into the slit coating mechanism. The substrate undergoes a first hard coating by the slit coating mechanism, followed by a second soft film coating by the secondary soft film coating mechanism to form a uniform perovskite wet film. The transport mechanism then conveys the substrate through a blow-drying assembly to blow-dry the perovskite wet film, forming a perovskite thin film. The perovskite thin film preparation apparatus provided by this invention can achieve one-step and two-step solution methods for film preparation. The secondary soft coating process can reduce or eliminate hard damage to the film, improving film quality. Automated control and continuous transport facilitate continuous large-area mass production using the solution method, improving production efficiency and reducing production costs. Attached Figure Description

[0043] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0044] Figure 1 This is a schematic diagram of the overall structure of the perovskite coating device provided in an embodiment of the present invention;

[0045] Figure 2 for Figure 1 A first-view structural schematic diagram of the slit coating mechanism in its installed state;

[0046] Figure 3 for Figure 1 A second-view structural schematic diagram of the slit coating mechanism in its installed state;

[0047] Figure 4 for Figure 1 A schematic diagram of the slit coating mechanism;

[0048] Figure 5 for Figure 1Structure diagram of the installation state of the secondary soft film coating mechanism;

[0049] Figure 6 For Figure 1 Structure diagram of the first perspective of the secondary soft film coating mechanism;

[0050] Figure 7 For Figure 1 Structure diagram of the second perspective of the secondary soft film coating mechanism;

[0051] Figure 8 For Figure 1 Structure diagram of the installation state of the air knife blowing mechanism;

[0052] Figure 9 For Figure 1 Structure diagram of the air knife blowing mechanism;

[0053] Figure 10 For Figure 1 Structure diagram of the pre-heating mechanism and the post-processing mechanism;

[0054] Figure 11 Optical picture of the sample prepared in Example 3 without anti-solvent participation and in the air knife blowing mode;

[0055] Figure 12 Optical picture of the sample prepared in Example 4 without anti-solvent participation and without the air knife blowing mode.

[0056] Icon: 100 - perovskite coating device; 001 - substrate; 002 - perovskite film; 003 - blowing and drying assembly; 110 - transmission mechanism; 111 - first transmission mechanism; 112 - second transmission mechanism; 120 - coating mechanism; 121 - slot coating mechanism; 1211 - first slot die; 1212 - second slot die; 1213 - feed port; 1214 - liquid storage cavity; 1215 - straight slot; 122 - secondary soft film coating mechanism; 1221 - front clamping plate; 1222 - rear clamping plate; 1223 - fixing piece; 1224 - soft film; 123 - first screw rod adjusting mechanism; 1231 - first fixed module; 124 - second screw rod adjusting mechanism; 1241 - second fixed module; 130 - air knife blowing mechanism; 131 - first blowing die; 132 - second blowing die; 133 - connecting port; 134 - air supply chamber; 1341 - main cavity; 1342 - connecting channel; 135 - linear slot air outlet; 140 - post-processing mechanism; 141 - top processing unit; 142 - bottom heating unit; 150 - fixed support; 151 - installation cross beam; 152 - first cross beam suspension arm; 153 - second cross beam suspension arm; 154 - third cross beam suspension arm; 155 - first universal ball shaft joint; 156 - second universal ball shaft joint; 160 - photoelectric sensing mechanism; 170 - pre-heating mechanism. DETAILED DESCRIPTION

[0057] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below. If specific conditions are not indicated in the embodiments, the conventional conditions or the conditions suggested by the manufacturers are adopted. If the manufacturers of the reagents or instruments are not indicated, the conventional products that can be purchased in the market are adopted.

[0058] In the description of the present application, it should be noted that the terms “center”, “upper”, “lower”, “left”, “right”, “vertical”, “horizontal”, “inner”, “outer” and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the present application is usually placed, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the device or element must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application. In addition, the terms “first”, “second”, “third” and the like are only used for differentiation in description, and cannot be understood as indicating or implying relative importance.

[0059] In addition, the terms “horizontal”, “vertical” and the like do not mean that the components must be absolutely horizontal or vertical, but can be slightly inclined. For example, “horizontal” only means that it is more horizontal relative to “vertical”, and does not mean that the structure must be completely horizontal, but can be slightly inclined.

[0060] The embodiment of the present application provides a perovskite coating device 100, please refer to Figure 1 , comprising a conveying mechanism 110, a coating mechanism 120, a blowing and drying assembly 003.

[0061] It should be noted that the conveying mechanism 110 is used to convey the substrate 001, so that the substrate 001 passes through the coating mechanism 120 and the blowing and drying assembly 003 in turn, and the precursor solution is coated on the substrate 001 to form a perovskite wet film when passing through the coating mechanism 120; then the blowing and drying assembly 003 blows and dries the perovskite wet film, accelerates the organic solvent volatilization and drying, and forms a perovskite thin film 002.

[0062] The conveying mechanism 110 can be a general conveyor belt or a roller conveyor, and the conveying speed can be 0 mm / s to 100 mm / s (preferably 0 mm / s to 60 mm / s). The substrate can be a structure pre-prepared with a bottom electrode functional layer. Specifically, the substrate material can be a hard conductive material such as indium tin oxide (ITO) conductive glass, fluorine-doped tin oxide (FTO) conductive glass, aluminum-doped zinc oxide (AZO) conductive glass, etc.; or a flexible conductive material such as polyvinyl alcohol (PVA), polyester (PET), polyimide (PI), polyethylene naphthalene glycol (PEN), polydimethylsiloxane (PDMS), copper foil, titanium plate, etc. The substrate material can be any of the above materials, but is not limited thereto.

[0063] In some embodiments, the blowing and drying assembly 003 comprises a wind knife blowing mechanism 130 and a post-processing mechanism 140 arranged in sequence in the conveying direction, the conveying mechanism 110 comprises a first conveying mechanism 111 and a second conveying mechanism 112 for receiving the output material of the first conveying mechanism 111, the coating mechanism 120 and the wind knife blowing mechanism 130 are installed above the first conveying mechanism 111, and the bottom heating unit 142 in the post-processing mechanism 140 is installed on the second conveying mechanism 112. There is a slight gap between the first conveying mechanism 111 and the second conveying mechanism 112, and the substrate 001 output from the first conveying mechanism 111 can fall into the second conveying mechanism 112. The conveying speeds of the first conveying mechanism 111 and the second conveying mechanism 112 can be controlled separately, the coating speed can be changed by adjusting the conveying speed of the first conveying mechanism 111, and the control of different post-processing annealing times can be realized by adjusting the conveying speed of the second conveying mechanism 112.

[0064] In some embodiments, a pre-heating mechanism 170 is further arranged on the first conveying mechanism 111. If the first conveying mechanism 111 is a roller, the roller itself can be provided with the pre-heating mechanism 170; if the first conveying mechanism 111 is a conveyor belt, the pre-heating mechanism 170 can be installed below the conveyor belt, and the conveyor belt can be a heat-resistant metal mesh belt. The pre-heating mechanism 170 pre-heats the substrate, the heating range is 20°C (room temperature) to 200°C, which can accelerate the volatilization and drying of the liquid film, and cooperates with the wind knife blowing mechanism 130 to improve the film forming quality.

[0065] The coating mechanism 120 comprises a slit coating mechanism 121 and a secondary soft film coating mechanism 122 arranged in sequence in the conveying direction, the precursor solution is coated on the substrate 001 by the slit coating mechanism 121, and the secondary coating is performed through the secondary soft film coating mechanism 122, so as to reduce or eliminate the hard damage of the film, improve the quality of the precursor liquid film, improve the flatness of the film, avoid the appearance of the bulk phase defects caused by the liquid film damage in the crystallization growth process of the film, and thus improve the battery photocurrent, fill factor and open circuit voltage and the like; moreover, the improvement of the flatness can also improve the uniformity of the large-area module battery and better adapt between different sub-batteries.

[0066] In some embodiments, referring to Figure 1 、 Figure 2 and Figure 3 , the conveying mechanism 110 is provided with a fixed support 150, the fixed support 150 is connected with a mounting beam 151, the slit coating mechanism 121 is mounted on the mounting beam 151 through a first screw rod adjusting mechanism 123, so as to adjust the height of the slit coating mechanism 121 through the first screw rod adjusting mechanism 123, so as to control the vertical distance between the coating slit outlet and the substrate 001 to be adjustable at 0cm-5cm. Specifically, the fixed support 150 is fixed on the workbench surface of the conveying mechanism 110, which can be in the shape of a gantry, but is not limited thereto.

[0067] In some embodiments, referring to Figure 4 , the slit coating mechanism 121 comprises a first slit die 1211 and a second slit die 1212 fixedly installed opposite to the first slit die 1211, at least one feed port 1213 for connecting an external liquid injection system is arranged on the first slit die 1211, a liquid storage cavity 1214 in communication with the feed port 1213 is formed in the interiors of the first slit die 1211 and the second slit die 1212, a direct-current slit 1215 is in communication with the bottom of the liquid storage cavity 1214, the direct-current slit 1215 extends from the liquid storage cavity 1214 to the bottom of the slit coating mechanism 121, and the direct-current slit 1215 extends from one end of the slit coating mechanism 121 in the horizontal direction to the other end opposite thereto, so as to output the coating liquid onto the substrate 001 through the direct-current slit 1215. The external liquid injection system delivers the precursor solution from the feed port 1213 into the liquid storage cavity 1214 through the components of the delivery pump, the liquid storage cavity 1214 can uniformly flow the precursor solution out of the direct-current slit 1215, so as to facilitate the trace control of the liquid output and coating, and ensure the coating stability and the film uniformity.

[0068] In some embodiments, the first slit die 1211 and the second slit die 1212 can be fixed by a fixing member such as a bolt, but are not limited thereto. The width of the direct-current slit 1215 is not limited and can be 0.1 μm to 500 μm. The width of the direct-current slit 1215 can be adjusted by adding a gasket. The liquid flow rate ranges from 0.001 mL / min to 20 mL / min.

[0069] In some embodiments, referring to Figure 1 、 Figures 5-7 The secondary soft film coating mechanism 122 includes a front clamping plate 1221, a rear clamping plate 1222, and a fixing member 1223 for fixing the front clamping plate 1221 and the rear clamping plate 1222. The soft film 1224 is clamped in the front clamping plate 1221 and the rear clamping plate 1222. The soft film 1224 extends towards the transmission mechanism to perform secondary coating on the material coated on the substrate 001. The secondary coating is achieved by the pressure and the contact angle of the soft film 1224 on the primary liquid film. The secondary coating can effectively repair the film damage caused by the primary hard coating, improve the quality of the precursor liquid film, and facilitate the replacement and cleaning of the soft film module through the clamping plate.

[0070] Specifically, the structure of the fixing member 1223 is not limited and can be a hexagonal bolt. The front and rear clamping plates clamp and place the soft film 1224 by loosening the hexagonal bolt. This structure facilitates the cleaning and replacement of the soft film.

[0071] Further, the first cross beam suspension arm 152 is also fixed on the mounting cross beam 151. The secondary soft film coating mechanism 122 is installed on the first cross beam suspension arm 152 through the second lead screw adjusting mechanism 124 to adjust the contact angle and the pressure of the secondary soft film coating mechanism 122 on the perovskite wet film through the second lead screw adjusting mechanism 124. The contact angle is adjustable between 0° and 90°.

[0072] Specifically, the structure of the first lead screw adjusting mechanism 123 and the second lead screw adjusting mechanism 124 is not limited and can be a structure capable of achieving coarse adjustment and fine adjustment. The lead screw adjustment is a manual adjustment, such as a screw micrometer, a differential head, or the like. The first lead screw adjusting mechanism 123 includes a first fixing module 1231. The slit coating mechanism 121 is connected to the first fixing module 1231 through a buckle or the like. The second lead screw adjusting mechanism 124 includes a second fixing module 1241. The secondary soft film coating mechanism 122 is connected to the second fixing module 1241 through a buckle or the like.

[0073] It can be understood that the lead screw adjustment of the first lead screw adjusting mechanism 123 and the second lead screw adjusting mechanism 124 is not limited to manual adjustment. It can also be automatically controlled by a circuit to achieve precise control and form a memory mode for storage and retrieval.

[0074] In some embodiments, the fixed support 150 is provided with a photoelectric sensing mechanism 160, which is connected to an external liquid injection system, so as to inject liquid by using the external liquid injection system when the substrate 001 is transmitted to the photoelectric sensing mechanism 160 by the transmission mechanism 110, and stop injecting liquid when no substrate passes.

[0075] Specifically, the external liquid injection system can include a container for storing a precursor solution, a delivery pump for delivering the precursor solution, and a controller for controlling the delivery pump to be turned on and off. When the photoelectric sensing mechanism 160 senses the substrate 001, a passing feedback signal is fed back to the controller in the external liquid injection system, and then the controller is used to control the delivery pump to deliver liquid; when no substrate passes, the liquid injection is stopped, realizing automatic control and continuous coating, and at the same time, continuous pumping of the precursor liquid can be avoided, which can cause pollution by dropping onto the workbench, and at the same time, the transmission mechanism 110 realizes continuous coating of the substrate.

[0076] It should be noted that the controller in the external liquid injection system can be an integrated circuit chip with signal processing capability. The above-mentioned controller can be a general-purpose processor, including a central processing unit (CPU), a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device, a discrete gate or transistor logic device, a discrete hardware component, which can realize or execute the disclosed methods, steps and logic block diagrams in the embodiments of the present application. The general-purpose processor can be a microprocessor, and the controller provided in the present embodiment can also be any conventional processor or the like.

[0077] In some embodiments, as Figure 1 and Figure 8, the perovskite coating device 100 further comprises a second cross beam suspension arm 153 and a third cross beam suspension arm 154, the first cross beam suspension arm 152 and the second cross beam suspension arm 153 are connected through a first universal ball shaft joint 155, the second cross beam suspension arm 153 and the third cross beam suspension arm 154 are connected through a second universal ball shaft joint 156, and an end of the third cross beam suspension arm 154 away from the second cross beam suspension arm 153 is connected with the air knife blowing mechanism 130. The first universal ball shaft joint 155 and the second universal ball shaft joint 156 can realize multi-dimensional adjustment of the front and rear distance, vertical height and blowing angle of the air knife blowing mechanism 130, accelerate the volatilization of organic solvents in the precursor liquid film without the participation of anti-solvents, improve the film forming quality, and improve the crystallinity and grain size of the thin film. The first cross beam suspension arm 152 and the first universal ball shaft joint 155 realize up-down and left-right adjustment, change the distance and blowing position between the air knife blowing mechanism 130 and the coating liquid film, and the second cross beam suspension arm 153 and the second universal ball shaft joint 156 realize front-back and left-right adjustment, change the blowing angle between the air knife blowing mechanism 130 and the coating liquid film. Specifically, the first universal ball shaft joint 155 and the second universal ball shaft joint 156 are existing connecting components, and their structure and working principle will not be described in detail here.

[0078] In some embodiments, referring to Figure 9 The air knife blowing mechanism 130 comprises a first blowing die head 131 and a second blowing die head 132 fixedly installed opposite to the first blowing die head 131. The first blowing die head 131 and the second blowing die head 132 are two die heads arranged opposite to each other on the left and right, and can be fixed by bolts or the like. At least one connecting port 133 for connecting the air supply system is arranged on the first blowing die head 131. The air supply chamber 134 is formed in the inner cavities of the first blowing die head 131 and the second blowing die head 132. The first blowing die head 131 and the second blowing die head 132 are arranged at intervals at the bottom to form a linear slit air outlet 135, and the linear slit air outlet 135 is in communication with the air supply chamber 134. The gas delivered by the air supply system enters the air supply chamber 134 through the connecting port and is output through the linear slit air outlet 135. The specific shape of the air supply chamber 134 is not limited.

[0079] In some embodiments, the air supply chamber 134 includes a main body chamber 1341 and a connecting passage 1342 for connecting the main body chamber 1341 and the linear slit air outlet 135, the width of the main body chamber 1341 is greater than the width of the linear slit air outlet 135, and the width of the connecting passage 1342 gradually decreases from top to bottom. The air supply chamber 134 is approximately pentagonal, which can uniformly distribute the air in the air supply system in the blowing device, and then blow out from the linear slit air outlet 135, ensuring that the air curtain is uniform, and the pentagonal air chamber can also achieve the effect of pressurization. The width of the linear slit air outlet 135 can be adjusted by adding a gasket, and the width range is 0.1 μm-500 μm, and the slit air speed is adjusted by pressure, and the pressure range is 0 MPa-1 MPa.

[0080] Specifically, the gas delivered by the air supply system can be any one of nitrogen, argon, dry air, etc. The vertical distance between the linear slit air outlet 135 (i.e. the lowest point of the air knife) and the substrate 001 is about 0 cm-10 cm adjustable; the blowing angle, the blowing direction is perpendicular to the substrate direction, and the left and right sides are adjustable between 0°-90°.

[0081] Please refer to Figure 1 and Figure 10 The post-processing mechanism 140 includes a top processing unit 141 and a bottom heating unit 142, the bottom heating unit 142 is installed on the transmission mechanism to heat from the bottom of the substrate 001, and the top processing unit 141 is oppositely arranged with the bottom heating unit 142, and the top processing unit 141 includes at least one of a heating component and a negative pressure air extraction component. The top processing unit 141 is used for heating and / or negative pressure air extraction from above, and the bottom heating unit 142 is used for annealing treatment from below, which accelerates the formation of perovskite film.

[0082] Specifically, the bottom heating unit 142 heats the substrate 001 from the bottom, and the heating range is 20℃-500℃, and the top processing unit 141 heats the film from the top, or performs negative pressure air extraction on the film from the top, or performs heating and negative pressure air extraction on the film from the top at the same time. The heating range of the top processing unit 141 on the post-processing mechanism 140 is 20℃ (room temperature)-500℃, and the negative pressure air extraction speed is 0 m / s-12 m / s.

[0083] In some embodiments, the top processing unit 141 is a heating and negative pressure integrated device, which can heat and perform negative pressure air extraction on the perovskite wet film after the substrate is transmitted to below the top processing unit 141. That is, the top processing unit 141 integrates the heating device and the negative pressure device to form an integrated structure, which has the functions of heating and negative pressure. Here, the heating mode can be any one of resistance wire, infrared, laser, etc.

[0084] As another embodiment, the bottom heating unit 142 performs heating baking from the bottom of the coated wet film, and the top processing unit 141 performs negative pressure air extraction treatment from the top of the coated wet film, so as to accelerate solution evaporation and drying to form the perovskite film. That is, the top processing unit 141 can only perform negative pressure air extraction.

[0085] As another embodiment, the bottom heating unit 142 performs heating baking from the bottom of the coated wet film, and the top processing unit 141 performs negative pressure air extraction treatment from the top of the coated wet film, so as to accelerate solution evaporation and drying to form the perovskite film. That is, the top processing unit 141 can only perform negative pressure air extraction.

[0086] The overall working principle of the perovskite coating device provided by the application is described as follows: the substrate 001 is conveyed to the preheating mechanism 170 by the first conveying mechanism 111, the preheating mechanism 170 preheats the substrate to be coated to improve the coating environment and facilitate rapid volatilization and drying of the precursor solution; when the substrate passes through the photoelectric induction mechanism 160, the photoelectric induction mechanism 160 controls the precursor solution pump to deliver the precursor solution to the slot coating mechanism 121, and the precursor solution is output to the substrate by the direct current slot 1215 to perform hard coating, and then the substrate is coated twice by the secondary soft film coating mechanism 122 to preliminarily form a perovskite wet film; the coated wet film is conveyed to the air knife blowing mechanism 130 for blowing, and then enters the post-processing mechanism 140 by the second conveying mechanism 112, and the top processing unit 141 performs heating baking and / or negative pressure air extraction from the top, and the bottom heating unit 142 performs annealing treatment from the bottom to accelerate the formation of the perovskite film 002.

[0087] The embodiment of the application also provides a preparation method of a perovskite film, which is prepared by using the preparation device of the perovskite film, and the preparation method comprises the following steps: conveying the substrate 001 by using the conveying mechanism 110, injecting the precursor solution into the slot coating mechanism 121 by using an external injection system when the substrate 001 is conveyed to the photoelectric induction mechanism 160, performing one-time hard coating on the substrate 001 by the slot coating mechanism 121, and then performing secondary coating on the substrate by the secondary soft film coating mechanism 122 to form a uniform perovskite wet film; and conveying the substrate by the conveying mechanism 110 to pass through the blowing and drying assembly 003 to blow and dry the perovskite wet film and form the perovskite film. The one-step solution method and the two-step solution method can be used to prepare the film, the secondary soft coating process can reduce or eliminate hard damage to the film, and the film quality is improved; automatic control is conducive to realizing continuous large-area and large-scale production of the solution method, improving production efficiency, and reducing production cost.

[0088] The preparation method can be a one-step solution method or a two-step solution method, and the specific process is as follows:

[0089] (1) One-step solution method

[0090] The step of preparing the perovskite film by the one-step solution method comprises: 1) placing a substrate 001 with a pre-prepared bottom electrode functional layer on a conveying shaft or conveying belt of a first conveying mechanism 111; 2) the substrate 001 passes through a photoelectric induction mechanism 160, and a liquid injection system starts liquid injection work; the substrate 001 passes through a slot coating mechanism 121, and a slot coating head coats a precursor solution on the upper surface of the substrate to form a first hard coating liquid film; 3) the first hard coating liquid film passes through a second soft film coating mechanism 122, and the liquid film is secondarily coated on the substrate under the action of compressive stress and shear stress to form a wet film with uniform thickness; 4) the wet film with uniform thickness passes through a preheating mechanism 170 and an air knife blowing mechanism 130, and the preheating and air knife blowing are combined to accelerate the volatilization of organic solvents in the wet film; 5) the film after blowing is conveyed by a second conveying mechanism 112 to a top processing unit 141 and a bottom heating unit 142 for post-processing of heating and annealing, so that the perovskite film is obtained.

[0091] When the perovskite film is prepared by the one-step solution method, the solute of the precursor solution used is at least one of one or more of ABX3, wherein A is at least one of a monovalent organic cation and a metal ion, such as one or more of CH3NH 3+ (MA + ), CH(NH2) 2+ (FA + ), Cs + and Rb + , B is one or more of metal ions such as Pb 2+ , Sn 2+ , Ag + , Bi 3+ , and X is a single component or mixed component halogen element such as I - , Br - , Cl - . The solvent of the precursor solution is one or a combination of isopropyl alcohol, methoxy ethanol, dimethyl formamide, dimethyl sulfoxide, N, N dimethyl acetamide, and N-methyl pyrrolidone, which can be any one or more of the above. The concentration of the precursor solution is 0.5 mol / L to 3 mol / L, such as 0.5 mol / L, 1.0 mol / L, 2.0 mol / L, 3.0 mol / L, etc.

[0092] The above preparation method provided by the embodiment of the present application is for preparing the perovskite film by the one-step solution method, which accelerates the drying of the film through air knife blowing and preheating treatment, does not use anti-solvent extraction, is more safe and environmentally friendly, and is conducive to the large-area continuous production of the perovskite film.

[0093] (2) Two-step solution method

[0094] The step of preparing the perovskite film by the two-step solution method comprises:

[0095] 1) Put the substrate 001 with a pre-prepared bottom electrode functional layer onto the conveying shaft or conveying belt of the first conveying mechanism 111;

[0096] 2) The substrate 001 passes through the photoelectric induction mechanism 160, and the liquid injection system starts the liquid injection work. The substrate 001 passes through the slot coating mechanism 121, and the slot coating head coats the first perovskite precursor solution metal halide on the upper surface of the substrate 001 to form a first hard coating liquid film;

[0097] 3) The first hard coating liquid film passes through the second soft film coating mechanism 122, and under the action of compressive stress and shear stress, the liquid film is coated on the substrate to form a wet film with uniform thickness;

[0098] 4) The wet film with uniform thickness passes through the pre-heating mechanism 170 and the air knife blowing mechanism 130, and the combination of pre-heating and air knife blowing accelerates the volatilization of organic solvents in the wet film;

[0099] 5) After the second conveying mechanism 112, the top processing unit 141 and the bottom heating unit 142 are conveyed to the film after blowing, the film is heated and annealed for post-processing, and the substrate with metal halide is obtained;

[0100] 6) The substrate with metal halide passes through the photoelectric induction mechanism 160, and the liquid injection system starts the liquid injection work. The substrate passes through the slot coating mechanism 121, and the slot coating head coats the second perovskite precursor solution organic halide on the upper surface of the substrate to form a first hard coating liquid film;

[0101] 7) The first hard coating liquid film passes through the second soft film coating mechanism 122, and under the action of compressive stress and shear stress, the liquid film is coated on the substrate to form a wet film with uniform thickness;

[0102] 8) The wet film with uniform thickness passes through the pre-heating mechanism 170 and the air knife blowing mechanism 130, and the combination of pre-heating and air knife blowing accelerates the volatilization of organic solvents in the wet film;

[0103] 9) After the second conveying mechanism 112, the top processing unit 141 and the bottom heating unit 142 are conveyed to the film after blowing, the film is heated and annealed for post-processing, and the perovskite film is obtained.

[0104] Among them, the solute of the first perovskite precursor solution (metal halide solution) is at least one of BX2, and the solute of the second perovskite precursor solution is at least one of AX, wherein A is at least one of monovalent organic cation and metal ion, such as CH3NH 3+ (MA + ), CH(NH2) 2+ (FA + ), Cs + and Rb +One or more of the following, where B is a metal ion, such as Pb. 2+ Sn 2+ Ag + Bi 3+ One or more of the following, where X is I - ,Br - Cl - The precursor solution is composed of single or mixed halogen elements. The solvent for the precursor solution is one or a combination of isopropanol, methoxyethanol, dimethylformamide, dimethyl sulfoxide, N,N-dimethylacetamide, and N-methylpyrrolidone, and can be any one or more of these. The concentration of metal halide in the first perovskite precursor solution is 0.2 mol / L to 3 mol / L, and the concentration of organic halide in the second perovskite precursor solution is 0.1 mol / L to 1 mol / L.

[0105] The preparation method provided in this embodiment of the invention is for the preparation of perovskite thin films by a two-step solution method. By using air knife purging and preheating treatment, the drying of metal halide films is accelerated. Organic halides react with metal halide films to form perovskite. Air knife purging accelerates the evaporation of organic solvents. At the same time, anti-solvent extraction is not used, which is safer and more environmentally friendly, and is conducive to the large-area continuous production of perovskite thin films.

[0106] It should be noted that the perovskite coating apparatus and perovskite film preparation method provided in the embodiments of the present invention can be used for coating other functional layer solutions besides the perovskite functional layer. The functional layer solution includes, but is not limited to, one or more of the following solutions: SnO2, TiO2, ZnO, WO3, Nb2O5, Sb2O5, V2O5, Fe2O3, Ta2O5, Zn2SnO4, and NiO. x CuO, Cu2O, CeO x , CdS, ZnS, Cs2S, MoS2, Bi2S3, CdSe, ZnSe, Cs2Se, CuSCN, PEDOT: PSS, P3HT, PCBM, C60, C70, PTAA, Spiro-OMeTAD, 2PACz, MeO-2PACz, MeO-4PACz, BCP.

[0107] The features and performance of the present invention will be further described in detail below with reference to embodiments.

[0108] It should be noted that the apparatus used in the following embodiments is... Figure 1 The device in the middle.

[0109] Example 1

[0110] This embodiment provides a method for preparing a perovskite thin film, comprising the following steps:

[0111] (1) MAI and PbI2 are dissolved in DMF / DMSO at a molar ratio of 1:1.05, and the volume ratio of DMF:DMSO is 4:1, to prepare a perovskite precursor solution of 1.3 mol / L. The perovskite precursor solution is loaded into the liquid injection system, the coating liquid flow rate is 1.5 mL / min, the vertical distance between the slit outlet and the substrate is 150 μm, and the contact angle between the secondary soft film and the substrate is adjusted to 30°.

[0112] (2) The preheating mechanism 170 is set to a temperature of 50°C.

[0113] (3) Turn on the air knife blowing mechanism 130, the vertical distance between the air knife lowest point and the substrate is 1 cm, the air outlet direction is 45° to the substrate, and the air outlet pressure is 0.2 MPa.

[0114] (4) Place the FTO substrate deposited with TiO2 on the first transmission mechanism 111, and the transmission speed is 60 mm / s before passing through the photoelectric induction mechanism 160, and the transmission speed is 5 mm / s after passing through the photoelectric induction mechanism 160.

[0115] (5) The first transmission mechanism 111 sequentially passes the substrate through the preheating mechanism 170 to preheat the substrate, passes through the slit coating mechanism 121 to coat the perovskite precursor liquid, passes through the secondary soft film coating mechanism 122 for secondary coating to improve the wet film coating quality, and passes through the air knife blowing mechanism 130 to accelerate the organic solvent evaporation.

[0116] (6) Turn on the second transmission mechanism 112, and the transmission speed is 10 mm / s.

[0117] (7) Turn on the top processing unit 141 and the bottom heating unit 142 to simultaneously bake the above coated wet film from top to bottom, and the temperature is set to 120°C, the heating time is 15 min, and the substrate with MAPbI3 perovskite film is obtained.

[0118] Example 2

[0119] The present embodiment provides a preparation method of perovskite film, comprising the following steps:

[0120] (1) FAI and PbI2 are dissolved in DMF / DMSO at a molar ratio of 1:1.05, and the volume ratio of DMF:DMSO is 9:1, to prepare a perovskite precursor solution of 1.5 mol / L. The perovskite precursor solution is loaded into the liquid injection system, the coating liquid flow rate is 5 mL / min, the vertical distance between the slit outlet and the substrate is 250 μm, and the contact angle between the secondary soft film and the substrate is adjusted to 45°.

[0121] (2) Open the air knife blowing mechanism 130, the vertical distance between the lowest point of the air knife and the substrate is 2 cm, the air outlet direction is 60° to the substrate, and the air outlet pressure is 0.5 MPa.

[0122] (3) Place the ITO substrate deposited with SnO2 on the first transmission mechanism 111, the conveying speed is 60 mm / s before the substrate passes through the photoelectric induction mechanism 160, and the conveying speed is 8 mm / s after the substrate passes through the photoelectric induction mechanism 160.

[0123] (4) The conveying device sequentially passes the substrate through the slot coating mechanism 121 to coat perovskite precursor solution, passes through the secondary soft film coating mechanism 122 for secondary coating to improve the wet film coating quality, and passes through the air knife blowing mechanism 130 to accelerate the volatilization of organic solvents.

[0124] (5) Open the second transmission mechanism 112, and the conveying speed is 6 mm / s.

[0125] (6) Open the bottom heating unit 142 to heat and bake from the bottom of the above coated wet film, open the top processing unit 141 to simultaneously perform negative pressure air exhaust treatment (negative pressure air exhaust speed is 8 m / s) from the top of the above coated wet film, accelerate solution evaporation and drying, the temperature is set to 150°C, the heating time is 20 min, and a substrate attached with a FAPbI3 perovskite film is obtained.

[0126] Example 3

[0127] The embodiment provides a preparation method of a perovskite film, comprising the following steps:

[0128] (1) Dissolve CsBr and PbI2 into DMF / DMSO according to a molar ratio of 1:1.05, prepare a perovskite precursor solution with a concentration of 1.1 mol / L, fill the perovskite precursor solution into a liquid injection system, the coating liquid flow rate is 2 mL / min, the vertical distance between the slot outlet and the substrate is 200 μm, and the contact angle between the secondary soft film and the substrate is adjusted to 60°.

[0129] (2) The preheating mechanism 170 is set to a temperature of 90°C.

[0130] (3) Open the air knife blowing mechanism 130, the vertical distance between the lowest point of the air knife and the substrate is 2 cm, the air outlet direction is 90° to the substrate, and the air outlet pressure is 0.4 MPa.

[0131] (4) Place the ITO substrate deposited with TiO2 on the first transmission mechanism 111, the conveying speed is 60 mm / s before the substrate passes through the photoelectric induction mechanism 160, and the conveying speed is 5 mm / s after the substrate passes through the photoelectric induction mechanism 160.

[0132] (5) The conveying device sequentially passes the substrate through the preheating mechanism 170 to preheat the substrate, coats the perovskite precursor solution through the slit coating mechanism 121, performs secondary coating through the secondary soft film coating mechanism 122 to improve the wet film coating quality, and accelerates the volatilization of the organic solvent through the air knife blowing mechanism 130.

[0133] (6) The second conveying mechanism 112 is opened, and the conveying speed is 15 mm / s.

[0134] (7) The bottom heating unit 142 is opened to heat and bake the wet film after coating from the bottom, and the top processing unit 141 is opened to simultaneously heat and bake the wet film after coating from the top and perform negative pressure suction treatment (negative pressure suction air speed 5 m / s) to accelerate solution evaporation and drying. The heating temperature is set to 270°C, the heating time is 8 min, and the substrate with the CsPbI2Br perovskite film attached is obtained, and the optical picture is as shown in Figure 8 .

[0135] Example 4

[0136] The embodiment provides a preparation method of a perovskite film, including the following steps:

[0137] (1) CsBr and PbI2 are dissolved into DMF / DMSO according to a molar ratio of 1:1.05 to prepare a perovskite precursor solution with a concentration of 1.1 mol / L. The perovskite precursor solution is loaded into a liquid injection system, the coating liquid flow rate is 2 mL / min, the vertical distance between the slit outlet and the substrate is 200 μm, and the contact angle between the secondary soft film and the substrate is adjusted to 60°.

[0138] (2) The preheating mechanism 170 is set to a temperature of 90°C.

[0139] (3) The ITO substrate with TiO2 deposited thereon is placed on the first conveying mechanism 111, and the conveying speed is 60 mm / s before the substrate passes through the photoelectric induction mechanism 160 and is 5 mm / s after the substrate passes through the photoelectric induction mechanism 160.

[0140] (4) The conveying device sequentially passes the substrate through the preheating mechanism 170 to preheat the substrate, coats the perovskite precursor solution through the slit coating mechanism 121, and performs secondary coating through the secondary soft film coating mechanism 122 to improve the wet film coating quality.

[0141] (5) The second conveying mechanism 112 is opened, and the conveying speed is 15 mm / s.

[0142] (6) Turn on the bottom heating unit 142 to heat and bake the wet film from the bottom after coating, and turn on the top processing unit 141 to heat and bake the wet film from the top after coating and perform negative pressure suction treatment (negative pressure suction air speed 5 m / s) at the same time, accelerate solution evaporation and drying, the heating temperature is set to 270℃, the heating time is 8 min, and the substrate with CsPbI2Br perovskite film is obtained.

[0143] As a comparative example, when the air knife system is not purged, the film forming quality of the film is obviously different from that when the air knife system is purged (Example 3), the film uniformity and flatness are poor, and the optical pictures of Example 3 and Example 4 are as shown in Figure 11 and Figure 12 .

[0144] Example 5

[0145] The embodiment provides a preparation method of a perovskite film, comprising the following steps:

[0146] (1) Dissolve PbI2 into DMSO to prepare a first perovskite precursor solution metal halide with a concentration of 1.6 mol / L, load the first perovskite precursor solution metal halide into a liquid injection system, the coating liquid flow rate is 3 mL / min, the vertical distance between the slit outlet and the substrate is 240 μm, and the contact angle between the secondary soft film and the substrate is adjusted to 60°.

[0147] (2) The preheating mechanism 170 is set to a temperature of 70℃.

[0148] (3) Turn on the air knife purging mechanism 130, the vertical distance between the lowest point of the air knife and the substrate is 1.5 cm, the air outlet direction is 60° to the substrate, and the air outlet pressure is 0.3 MPa.

[0149] (4) Place the FTO substrate on which SnO2 is deposited on the first conveying mechanism 111, the conveying speed is 60 mm / s before the substrate passes through the photoelectric induction mechanism 160, and the conveying speed is 5 mm / s after the substrate passes through the photoelectric induction mechanism 160.

[0150] (5) The conveying device sequentially passes the substrate through the preheating mechanism 170 to preheat the substrate, passes the substrate through the slit coating mechanism 121 to coat the first perovskite precursor solution metal halide, passes the substrate through the secondary soft film coating mechanism 122 to perform secondary coating, improves the wet film coating quality, and passes the substrate through the air knife purging mechanism 130 to accelerate the volatilization of the organic solvent.

[0151] (6) Turn on the second conveying mechanism 112, and the conveying speed is 40 mm / s.

[0152] (7) Turn on the top processing unit 141 and the bottom heating unit 142 to simultaneously bake the wet film after coating from top and bottom, set the temperature to 70°C, and the heating time to 2 min, to obtain a substrate with PbI2metal halide attached.

[0153] (8) Dissolve FAI and MABr into isopropanol at a molar ratio of 0.95:0.05 to configure a second perovskite precursor solution organic halide at 0.5 mol / L, load the second perovskite precursor solution organic halide into the liquid injection system, the coating liquid flow rate is 10 mL / min, the vertical distance between the slit outlet and the substrate is 300 μm, and the contact angle between the secondary soft film and the substrate is adjusted to 30°.

[0154] (9) Turn on the air knife blowing mechanism 130, the vertical distance between the air knife lowest point and the substrate is 1.5 cm, the air outlet direction is 60° to the substrate, and the air outlet pressure is 0.3 MPa.

[0155] (10) Place the substrate with PbI2metal halide attached on the first transmission mechanism 111, the transmission speed is 60 mm / s before the substrate passes through the photoelectric induction mechanism 160, and the transmission speed is 10 mm / s after the substrate passes through the photoelectric induction mechanism 160.

[0156] (11) The conveying device sequentially passes the substrate through the slit coating mechanism 121 to coat the second perovskite precursor solution organic halide, through the secondary soft film coating mechanism 122 for secondary coating to improve the wet film coating quality, and through the air knife blowing mechanism 130 to accelerate the evaporation of the organic solvent.

[0157] (12) Turn on the second transmission mechanism 112, and the transmission speed is 3 mm / s.

[0158] (13) Turn on the bottom heating unit 142 to heat and bake the wet film after coating from the bottom, and turn on the top processing unit 141 to simultaneously heat and bake the wet film after coating from the top and perform negative pressure air extraction treatment (negative pressure air extraction speed 10 m / s) to accelerate the solution evaporation and drying, set the temperature to 150°C, and the heating time to 30 min, to obtain a substrate with perovskite thin film of MA 0.05 FA 0.95 PbI 2.95 Br 0.05 attached.

[0159] Example 6

[0160] The embodiment provides a preparation method of perovskite thin film, including the following steps:

[0161] (1) PbI2 is dissolved in DMF to prepare a first perovskite precursor solution metal halide with a concentration of 1.3 mol / L. The first perovskite precursor solution metal halide is loaded into a liquid injection system. The liquid coating flow rate is 2 mL / min. The vertical distance between the slit outlet and the substrate is 160 μm. The contact angle between the secondary soft film and the substrate is adjusted to 45°.

[0162] (2) The preheating mechanism 170 is set to a temperature of 60°C.

[0163] (3) The air knife blowing mechanism 130 is turned on. The vertical distance between the lowest point of the air knife and the substrate is 5 cm. The air outlet direction is 90° to the substrate. The air outlet pressure is 0.5 MPa.

[0164] (4) The FTO substrate on which PTAA is deposited is placed on the first conveying mechanism 111. The conveying speed is 60 mm / s before the substrate passes through the photoelectric induction mechanism 160, and the conveying speed is 8 mm / s after the substrate passes through the photoelectric induction mechanism 160.

[0165] (5) The conveying device sequentially passes the substrate through the preheating mechanism 170 to preheat the substrate, through the slit coating mechanism 121 to coat the first perovskite precursor solution metal halide, through the secondary soft film coating mechanism 122 for secondary coating to improve the wet film coating quality, and through the air knife blowing mechanism 130 to accelerate the evaporation of the organic solvent.

[0166] (6) The second conveying mechanism 112 is turned on, and the conveying speed is 40 mm / s.

[0167] (7) The bottom heating unit 142 is turned on to heat and bake the wet film from the bottom of the above-coated wet film. The top processing unit 141 is turned on to simultaneously perform negative pressure air suction treatment (negative pressure air suction speed of 6 m / s) from the top of the above-coated wet film, thereby accelerating the evaporation and drying of the solution. The heating temperature is set to 70°C, and the heating time is 2 min. A substrate with PbI2 metal halide attached thereto is obtained.

[0168] (8) FAI and MAI are dissolved in isopropanol at a molar ratio of 0.85:0.15 to prepare a second perovskite precursor solution organic halide with a concentration of 0.4 mol / L. The second perovskite precursor solution organic halide is loaded into a liquid injection system. The liquid coating flow rate is 15 mL / min. The vertical distance between the slit outlet and the substrate is 400 μm. The contact angle between the secondary soft film and the substrate is adjusted to 60°.

[0169] (9) The air knife blowing mechanism 130 is turned on. The vertical distance between the lowest point of the air knife and the substrate is 1 cm. The air outlet direction is 45° to the substrate. The air outlet pressure is 0.4 MPa.

[0170] (10) The substrate with PbI2metal halide attached is placed on the first transmission mechanism 111, the transmission speed is 60 mm / s before the substrate passes through the photoelectric induction mechanism 160, and the transmission speed is 15 mm / s after the substrate passes through the photoelectric induction mechanism 160.

[0171] (11) The conveying device sequentially coats the substrate with the second perovskite precursor solution organic halide through the slot coating mechanism 121, performs secondary coating through the secondary soft film coating mechanism 122 to improve the wet film coating quality, and accelerates the evaporation of the organic solvent through the air knife blowing mechanism 130.

[0172] (12) The second transmission mechanism 112 is opened, and the transmission speed is 8 mm / s.

[0173] (13) The bottom heating unit 142 is opened to heat and bake the wet film from the bottom after coating, and the top processing unit 141 is opened to simultaneously heat and bake the wet film from the top after coating and perform negative pressure air exhaust treatment (negative pressure air exhaust speed 10 m / s), which accelerates the evaporation and drying of the solution. The heating temperature is set to 150°C, and the heating time is 20 min, to obtain a substrate with MA 0.15 FA 0.85 PbI3perovskite thin film.

[0174] Example 7

[0175] The embodiment provides a preparation method of a perovskite thin film, comprising the following steps:

[0176] (1) PbI2is dissolved in NMP to prepare a first perovskite precursor solution metal halide with a concentration of 1.1 mol / L. The first perovskite precursor solution metal halide is loaded into a liquid injection system, the coating liquid flow rate is 1.5 mL / min, the vertical distance between the slot outlet and the substrate is 120 μm, and the contact angle between the secondary soft film and the substrate is adjusted to 60°.

[0177] (2) The air knife blowing mechanism 130 is opened, the vertical distance between the lowest point of the air knife and the substrate is 2 cm, the air outlet direction is 45° to the substrate, and the air outlet pressure is 0.2 MPa.

[0178] (3) The FTO substrate with NiO x deposited thereon is placed on the first transmission mechanism 111, the transmission speed is 60 mm / s before the substrate passes through the photoelectric induction mechanism 160, and the transmission speed is 6 mm / s after the substrate passes through the photoelectric induction mechanism 160.

[0179] (4) The conveying device sequentially coats the substrate with the first perovskite precursor solution metal halide through the slot coating mechanism 121, performs secondary coating through the secondary soft film coating mechanism 122 to improve the wet film coating quality, and accelerates the evaporation of the organic solvent through the air knife blowing mechanism 130.

[0180] (5) Open the second transmission mechanism 112, the transmission speed is 40 mm / s.

[0181] (6) Open the bottom heating unit 142 to heat and bake from the bottom of the wet film after coating, and open the top processing unit 141 to perform negative pressure suction treatment (negative pressure suction air speed 4 m / s) from the top of the wet film after coating at the same time, accelerate solution evaporation and drying, the temperature is set to 70°C, and the heating time is 2 min, to obtain a substrate attached with PbI2metal halide.

[0182] (7) Dissolve CsI, FAI and MABr into a methoxyethanol and NMP mixed solution in a molar ratio of 0.05:0:75:0.2, wherein the volume ratio of methoxyethanol to NMP is 9:1, to configure a second perovskite precursor solution organic halide of 0.8 mol / L, load the second perovskite precursor solution organic halide into the liquid injection system, the coating liquid flow rate is 12 mL / min, the vertical distance between the slit outlet and the substrate is 180 μm, and the contact angle between the secondary soft film and the substrate is adjusted to 60°.

[0183] (8) Open the air knife blowing mechanism 130, the vertical distance between the air knife lowest point and the substrate is 4.5 cm, the air outlet direction is 45° to the substrate, and the air outlet pressure is 0.6 MPa.

[0184] (9) Place the substrate attached with PbI2metal halide on the first transmission mechanism 111, the transmission speed is 60 mm / s before the substrate passes through the photoelectric induction mechanism 160, and the transmission speed is 15 mm / s after the substrate passes through the photoelectric induction mechanism 160.

[0185] (10) The conveying device sequentially passes the substrate through the slit coating mechanism 121 to coat the second perovskite precursor solution organic halide, passes through the secondary soft film coating mechanism 122 for secondary coating to improve the wet film coating quality, and passes through the air knife blowing mechanism 130 to accelerate the organic solvent volatilization.

[0186] (11) Open the second transmission mechanism 112, the transmission speed is 8 mm / s.

[0187] (12) Open the bottom heating unit 142 to heat and bake from the bottom of the wet film after coating, open the top processing unit 141 to perform heating and baking and negative pressure suction treatment (negative pressure suction air speed 8 m / s) from the top of the wet film after coating at the same time, accelerate solution evaporation and drying, and the heating temperature is set to 120°C, and the heating time is 30 min, to obtain a substrate attached with Cs 0.05 MA 0.2 FA 0.75P bI 2.8 Br 0.2Substrate of perovskite thin film.

[0188] The above description is merely that of the preferred embodiments of the application and is not intended to limit its scope. Many modifications and variations will be apparent to those skilled in the art. Embodiments may be practiced otherwise than as specifically described without departing from the spirit and scope of the application. Any references cited herein are incorporated by reference.

Claims

1. An apparatus for preparing perovskite thin films, characterized in that, include: The system includes a transmission mechanism for transmitting the substrate, a photoelectric sensing mechanism for sensing the position of the substrate, a coating mechanism for coating the surface of the substrate to form a perovskite wet film, and a purging and drying assembly for post-processing the perovskite wet film formed after coating. The coating mechanism and the blowing and drying assembly are arranged sequentially in the transmission direction of the transmission mechanism, so that the substrate is transported sequentially through the coating mechanism and the blowing and drying assembly by the transmission mechanism. The coating mechanism includes a slit coating mechanism and a secondary soft film coating mechanism arranged sequentially in the transport direction. The installation position of the photoelectric sensing mechanism corresponds to the slit coating mechanism. The photoelectric sensing mechanism is connected to an external liquid injection system so that when the substrate is transported to the photoelectric sensing mechanism, the external liquid injection system can be used to inject liquid into the slit coating mechanism. The slit coating mechanism includes a first slit die and a second slit die fixedly mounted opposite to the first slit die. The first slit die is provided with at least one inlet for connecting to an external liquid injection system. The interior of the first slit die and the second slit die are formed with a liquid storage cavity communicating with the inlet. The bottom of the liquid storage cavity is connected to a direct current slit. The direct current slit extends from the liquid storage cavity to the bottom of the slit coating mechanism and extends from one end of the slit coating mechanism in the horizontal direction to the opposite end, so as to output coating liquid onto the substrate through the direct current slit. The secondary soft film coating mechanism includes a front clamping plate, a rear clamping plate, and a fixing member for fixing the front clamping plate and the rear clamping plate. A soft film is held between the front clamping plate and the rear clamping plate, and the soft film extends toward the conveying mechanism to perform secondary coating on the material coated on the substrate. The purging and drying assembly includes an air knife purging mechanism and a post-processing mechanism arranged sequentially in the conveying direction. The post-processing mechanism includes a top processing unit and a bottom heating unit. The bottom heating unit is mounted on the conveying mechanism to heat the substrate from the bottom. The top processing unit is arranged opposite to the bottom heating unit. The top processing unit is a heating and negative pressure integrated device to simultaneously heat and / or vacuum the perovskite wet film after the substrate is conveyed to the bottom of the top processing unit. The transmission mechanism is provided with a fixed bracket, and a mounting beam is connected to the fixed bracket. The slit coating mechanism is installed on the mounting beam through a first screw adjustment mechanism so that the height of the slit coating mechanism can be adjusted through the first screw adjustment mechanism. A first crossbeam suspension arm is also fixed on the mounting crossbeam. The secondary soft film coating mechanism is mounted on the first crossbeam suspension arm through a second screw adjustment mechanism, so as to adjust the contact angle and pressure of the secondary soft film coating mechanism on the perovskite wet film through the second screw adjustment mechanism.

2. The apparatus for preparing perovskite thin films according to claim 1, characterized in that, It also includes a second crossbeam suspension arm and a third crossbeam suspension arm. The first crossbeam suspension arm and the second crossbeam suspension arm are connected by a first universal joint. The second crossbeam suspension arm and the third crossbeam suspension arm are connected by a second universal joint. The end of the third crossbeam suspension arm away from the second crossbeam suspension arm is connected to the air knife blowing mechanism.

3. The apparatus for preparing perovskite thin films according to claim 1, characterized in that, The air knife purging mechanism includes a first purging die head and a second purging die head that is opposite to and fixedly installed with the first purging die head. At least one connection port for connecting to an air supply system is provided on the first purging die head. An air supply chamber is formed in the inner cavity of the first purging die head and the second purging die head. The first purging die head and the second purging die head are spaced apart at the bottom to form a linear slit air outlet. The linear slit air outlet communicates with the air supply chamber. The air supply chamber includes a main chamber and a connecting channel for connecting the main chamber and the linear slit air outlet. The width of the main chamber is greater than the width of the linear slit air outlet, and the width of the connecting channel gradually decreases from the top to the bottom.

4. The apparatus for preparing perovskite thin films according to claim 1, characterized in that, The transmission mechanism includes a first transmission mechanism and a second transmission mechanism for receiving the material output from the first transmission mechanism. The coating mechanism and the air knife blowing mechanism are installed above the first transmission mechanism. The bottom heating unit in the post-processing mechanism is installed on the second transmission mechanism. A preheating mechanism is also provided on the first transmission mechanism.

5. A method for preparing a perovskite thin film, characterized in that, The perovskite thin film is prepared using the apparatus described in any one of claims 1-4, comprising: The substrate is transported using a transport mechanism. When the substrate is transported to the photoelectric sensing mechanism, a precursor solution is injected into the slit coating mechanism using an external liquid injection system. The substrate undergoes a first hard coating through the slit coating mechanism and then a second coating through the secondary soft film coating mechanism to form a uniform perovskite wet film. The transport mechanism conveys the substrate through the blow-drying assembly to blow-dry the perovskite wet film, forming a perovskite thin film.

6. The preparation method according to claim 5, characterized in that, The preparation method has at least one of the following characteristics a1-a13: Feature a1: The distance between the bottom of the DC slit on the slit coating mechanism and the substrate is 0cm~5cm; Feature a2: The liquid flow rate of the slit coating mechanism is 0.001 mL / min to 20 mL / min; Feature a3: The width of the DC slit on the slit coating mechanism is 0.1µm~500µm; Feature a4: The contact angle between the soft film on the secondary soft film coating mechanism and the substrate is 0°~90°; Feature a5: The distance between the lowest point of the air knife blowing mechanism and the substrate is 0cm~10cm; Feature a6: The width of the linear slit outlet on the air knife purging mechanism is 0.1µm~500µm; Feature a7: The pressure of the linear slit outlet on the air knife purging mechanism is 0MPa~1MPa; Feature a8: The heating temperature of the preheating mechanism is 20°C ~ 200°C; Feature a9: The transmission rate of the transmission mechanism is 0mm / s to 100mm / s; Feature a10: The heating range of the bottom heating unit on the post-processing mechanism is 20°C ~ 500°C; Feature a11: The heating range of the top processing unit on the post-processing mechanism is 20°C ~ 500°C; Feature a12: The negative pressure exhaust velocity of the top treatment unit on the post-treatment mechanism is 0m / s~12m / s; Feature a13: The preparation method is to prepare perovskite thin films by a one-step solution method or a two-step solution method; When preparing perovskite thin films using a one-step solution method, the solute in the precursor solution is one or more of ABX3, wherein A is at least one of a monovalent organic cation and a metal ion, B is a metal ion, and X is at least one halogen element. The two-step solution method for preparing perovskite thin films includes: firstly, coating with a first perovskite precursor solution, and then forming a substrate with metal halide attached after passing through a blow-drying assembly; then coating the substrate with metal halide attached with a second perovskite precursor solution, and forming a perovskite thin film after passing through a blow-drying assembly. Wherein, the solute of the first perovskite precursor solution is at least one of BX2, and the solute of the second perovskite precursor solution is at least one of AX, wherein A is at least one of monovalent organic cation and metal ion, B is a metal ion, and X is at least one halogen element. The solvents used to prepare the precursor solution, the first perovskite precursor solution, and the second perovskite precursor solution are all selected from isopropanol, methoxyethanol, dimethylformamide, dimethyl sulfoxide, N,N-dimethylacetamide, and N... At least one of methylpyrrolidone.

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