Preparation method and production equipment of perovskite solar cell absorption layer

Abstract

The invention discloses a preparation method and production equipment of a perovskite solar cell absorption layer. The production equipment comprises a workbench; the movable carrying device is mounted on the workbench in a sliding manner, and the movable carrying device is used for carrying and transporting a base; an inkjet printing device; the preparation method comprises the following steps of: taking formamidine tin iodide, cesium tin iodide and 6, 6-phenyl-C61-methyl butyrate as a precursor mixture, adding a solvent, and stirring to obtain a precursor solution; the method comprises the following steps: cleaning a substrate by using ultrasonic waves to remove surface stains, washing by using deionized water, and drying; coating the precursor solution obtained in the step S1 on the substrate obtained in the step S2 in an ink-jet printing manner; and S3, drying the coated substrate in the step S3 to remove moisture, and annealing to obtain the perovskite solar cell absorption layer. And the separation efficiency and the directional transmission capability of charges are improved, so that the photoelectric conversion efficiency of the perovskite solar cell is remarkably improved.

Description

Technical Field

[0001] The present invention relates to the technical field of solar cell production equipment, and in particular to a method for preparing a perovskite solar cell absorption layer and its production equipment, and more particularly to a solid-state device that uses a combination of organic materials and other materials as an active part, and is specifically suitable for the field of methods or equipment for manufacturing or processing such devices or their components. Background Art

[0002] At present, the technical solution for forming the perovskite functional layer (absorption layer) of perovskite solar cells is usually a one-step method, that is, the perovskite solution is coated on the substrate (including rigid substrates such as glass substrates, or flexible substrates, or silicon wafers, or ceramics) by slit coating. Other film layers of perovskite solar cells or other thin-film solar cells, including buffer layers (interface regulation layers), hole transport layers, electron transport layers, etc., are usually formed by magnetron sputtering (PVD), vacuum evaporation, or atomic layer deposition (ALD).

[0003] Whether it is slit coating or vacuum process (including PVD, vacuum evaporation and ALD), the deposition of various functional layers for thin-film solar cells faces the problems of slow production cycle and large equipment footprint. The information disclosed in this background technology section is only intended to increase the understanding of the overall background of the invention, and should not be regarded as an admission or any form of implication that the information constitutes prior art already known to those skilled in the art. Summary of the invention

[0004] The present invention overcomes the deficiencies of the prior art and provides a method for preparing a perovskite solar cell absorption layer and a production device thereof.

[0005] To achieve the above object, the technical solution adopted by the present invention is: a method for preparing an absorption layer of a perovskite solar cell, comprising the following steps:

[0006] S1: Formamidine tin iodide, cesium tin iodide and 6,6-phenyl-C61-butyric acid methyl ester are used as a precursor mixture, a solvent is added, and the mixture is stirred to obtain a precursor solution;

[0007] S2: The substrate is cleaned by ultrasonic cleaning to remove surface stains, then rinsed with deionized water and dried;

[0008] S3: coating the precursor solution obtained in S1 on the substrate obtained in S2 by inkjet printing;

[0009] S4: drying the substrate coated in S3 to remove moisture, and annealing the substrate to obtain a perovskite solar cell absorption layer.

[0010] In a preferred embodiment of the present invention, in S1, the molar ratio of formamidine tin iodide, cesium tin iodide and 6,6-phenyl-C61-butyric acid methyl ester is 1:1:0.3-1, the stirring parameters are 300-500r / min, the stirring temperature is 55-65°C, and the stirring time is 1-2.5h.

[0011] In a preferred embodiment of the present invention, in S1, the solvent is selected from one or a mixture of dimethyl sulfoxide, dimethylformamide, dimethylacetamide or N-methylpyrrolidone, and the ratio of the precursor mixture to the solvent is 1 mol of the precursor mixture and 1.5-2.5 L of the solvent is added.

[0012] In a preferred embodiment of the present invention, in S2, drying is performed by blowing hot air, the hot air temperature is 80-100° C., and the time is 20-30 minutes.

[0013] In a preferred embodiment of the present invention, in S3, the inkjet printing accuracy is 10 μm, the speed is 10 m / s, and the droplet size is 5 nL.

[0014] In a preferred embodiment of the present invention, in S4, the drying temperature is 75-85°C, and the time is 0.5-1.5h; the annealing temperature is 100-200°C, and the time is 20-40min.

[0015] A production device for a perovskite solar cell absorption layer comprises: a workbench, a mobile loading device arranged on the workbench, an inkjet printing device and a drying device,

[0016] A mobile loading device is slidably mounted on the workbench, and the mobile loading device is used to carry and transport the substrate;

[0017] An inkjet printing device is installed on the workbench and is arranged above the moving loading device;

[0018] The drying device is installed on the workbench and arranged above the moving object carrier. Along the transport direction of the substrate, the drying device is located downstream of the inkjet printing device.

[0019] In a preferred embodiment of the present invention, a linear motion mechanism is provided on the workbench, the linear motion mechanism includes a slide rail, and the mobile carrier is slidably installed on the slide rail; a loading device and a unloading device are also provided on both sides of the mobile carrier.

[0020] In a preferred embodiment of the present invention, the mobile loading device includes a loading seat and a loading mechanism, the loading seat is slidably connected to the slide rail, a base is arranged on the loading mechanism, a lifting mechanism is arranged on the loading seat, a horizontal moving mechanism is arranged on the lifting mechanism, and the loading mechanism is installed on the horizontal moving mechanism.

[0021] In a preferred embodiment of the present invention, the carrying mechanism includes a paper roll transmission belt, which is used to carry and transport the substrate. A vacuum absorber is provided below the paper roll transmission belt, which is used to absorb the substrate onto the paper roll transmission belt.

[0022] The present invention solves the defects existing in the background technology and has the following beneficial effects:

[0023] (1) The present invention provides a method for preparing an absorption layer of a perovskite solar cell and a production device thereof, wherein during the preparation process of the perovskite solar cell, a 6,6-phenyl-C61-butyric acid methyl ester molecule having an electric dipole moment is introduced, and the 6,6-phenyl-C61-butyric acid methyl ester molecule is mixed with tin iodine and cesium tin iodine to form an absorption layer, and the electric dipole moment characteristics of the 6,6-phenyl-C61-butyric acid methyl ester molecule enable the 6,6-phenyl-C61-butyric acid methyl ester molecule to form a dipole layer with tin iodine and cesium tin iodine at the interface, and the dipole layer generates an additional built-in electric field. Under illumination conditions, the built-in electric field can more effectively promote the separation of photogenerated charges (electrons and holes), and guide them to be directionally transmitted to the electron transport layer and the hole transport layer, respectively, thereby reducing the recombination loss of electron-hole pairs, improving the separation efficiency and directional transmission capability of charges, and thus significantly improving the photoelectric conversion efficiency of the perovskite solar cell.

[0024] (2) The present invention provides a method for preparing a perovskite solar cell absorption layer and a production device thereof, wherein energy level alignment is achieved by introducing 6,6-phenyl-C61-butyric acid methyl ester molecules at the interface of tin iodine and cesium tin iodine. By introducing 6,6-phenyl-C61-butyric acid methyl ester, the energy level arrangement at the interface of tin iodine and cesium tin iodine is adjusted, so that electrons can more easily cross the interface barrier and be transferred from the perovskite layer to the electron transport layer. This optimization of energy level alignment reduces the electron extraction barrier and reduces the energy loss of electrons during the transmission process, thereby improving the separation efficiency of carriers and reducing the recombination loss of electron-hole pairs. This helps to improve the stability and photoelectric conversion efficiency of perovskite solar cells.

[0025] (3) The present invention provides a method for preparing an absorption layer of a perovskite solar cell and a production device thereof. The electric dipole effect of 6,6-phenyl-C61-butyric acid methyl ester is utilized to increase the work function difference between the cathode and the anode, as well as the work function difference between the upper and lower surfaces of the perovskite film. The electric dipole effect of 6,6-phenyl-C61-butyric acid methyl ester is used to enhance the built-in electric field of the perovskite solar cell. The built-in electric field not only promotes the separation and directional transmission of photogenerated charges, but also increases the transmission speed of charges within the battery, and reduces the recombination probability of charges during transmission, thereby improving the charge collection efficiency. This significantly enhances the transmission and collection efficiency of charges in the perovskite solar cell, and further improves the photoelectric conversion performance and stability of the battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art are briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative work.

[0027] Figure 1 It is a three-dimensional schematic diagram of a production device for a perovskite solar cell according to an embodiment of the present invention;

[0028] Figure 2 A top view of a production device for a perovskite solar cell according to an embodiment of the present invention;

[0029] Figure 3 is a three-dimensional schematic diagram of a mobile loading device in one embodiment of the present invention;

[0030] In the picture;

[0031] 1. Workbench; 11. Table; 12. Linear motion mechanism; 121. Slide rail; 2. Mobile loading device; 21. Loading seat; 22. Loading mechanism; 221. Paper roll transmission belt; 23. Lifting mechanism; 24. Horizontal moving mechanism; 25. Horizontal rotating mechanism; 3. Inkjet printing device; 4. Drying device; 5. Loading device; 6. Unloading device; 7. Image detection device; 8. Base. DETAILED DESCRIPTION

[0032] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein. Therefore, the protection scope of the present invention is not limited to the specific embodiments disclosed below.

[0034] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the scope of protection of the present application. In addition, the terms "first", "second", etc. are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the invention, unless otherwise specified, "multiple" means two or more.

[0035] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood by specific circumstances.

[0036] like Figure 1 As shown, a method for preparing an absorption layer of a perovskite solar cell comprises the following steps:

[0037] S1: Formamidine tin iodide, cesium tin iodide and 6,6-phenyl-C61-butyric acid methyl ester are used as a precursor mixture, a solvent is added, and the mixture is stirred to obtain a precursor solution;

[0038] Among them, the molar ratio of formamidine tin iodide, cesium tin iodide and 6,6-phenyl-C61-butyric acid methyl ester is 1:1:0.3-1, the stirring parameters are 300-500r / min, the stirring temperature is 55-65°C, and the stirring time is 1-2.5h; the solvent is selected from one or a mixture of two of dimethyl sulfoxide, dimethylformamide, dimethylacetamide or N-methylpyrrolidone, and the ratio of the precursor mixture to the solvent is 1 mol of the precursor mixture, and 1.5-2.5L of the solvent is added.

[0039] It should be noted that 6,6-phenyl-C61-butyric acid methyl ester is a fullerene derivative molecule, whose molecular structure contains one or more substituents (such as alkyl, ester, etc.) connected to the fullerene cage. This special molecular structure makes the positive and negative charge centers inside the 6,6-phenyl-C61-butyric acid methyl ester molecule no longer overlap. Specifically, the fullerene cage itself has a certain charge distribution, while the substituent may have an opposite charge or a different charge density, resulting in an uneven charge distribution inside the entire molecule. In the 6,6-phenyl-C61-butyric acid methyl ester molecule, due to the charge transfer or interaction between the substituent and the fullerene cage, the positive and negative charge centers inside the molecule are offset, forming a tiny electric field. The direction of this electric field is consistent with the direction of the electric dipole moment, and the magnitude is proportional to the value of the electric dipole moment.

[0040] Therefore, when 6,6-phenyl-C61-butyric acid methyl ester is mixed with tin iodide and cesium tin iodide, charge redistribution and interaction will occur at their interface. Due to the electric dipole of 6,6-phenyl-C61-butyric acid methyl ester molecules, it will have a specific interaction with tin iodide and cesium tin iodide molecules at the interface. This interaction will cause 6,6-phenyl-C61-butyric acid methyl ester molecules to form an orderly arrangement at the interface, forming a dipole layer. This dipole layer can generate an additional built-in electric field, and the direction of this electric field is consistent with the direction of photogenerated charge separation in perovskite solar cells. When sunlight shines on a perovskite solar cell, photons are absorbed by the perovskite layer and stimulate photogenerated electrons and holes. These photogenerated electrons and holes are separated under the action of the built-in electric field. Electrons are directed to the electron transport layer, i.e., 6,6-phenyl-C61-butyric acid methyl ester, while holes are directed to the hole transport layer. The additional built-in electric field generated by the interface dipole layer enhances this separation process, allowing more photogenerated charges to be effectively separated and transported. After separation, the photogenerated electrons and holes are transmitted in a specific direction under the action of the built-in electric field. The interface dipole layer ensures that the electrons and holes can be transmitted along the correct path, reducing their collision and recombination probability during the transmission process. In the absence of an interface dipole layer, photogenerated electrons and holes may recombine due to collisions during the transmission process, resulting in energy loss. The presence of the interface dipole layer reduces this recombination loss, allowing more photogenerated charges to be effectively collected and converted into electrical energy.

[0041] The 6,6-phenyl-C61-butyric acid methyl ester molecule has a specific electronic structure and energy level distribution. When 6,6-phenyl-C61-butyric acid methyl ester is introduced into the interface of tin iodide and cesium tin iodide, its molecular energy level interacts with the energy level of the perovskite material, thereby adjusting the energy level arrangement at the interface. In the absence of 6,6-phenyl-C61-butyric acid methyl ester, the electron extraction barrier at the interface of tin iodide and cesium tin iodide is high, making it difficult for electrons to transfer from the perovskite layer to the electron transport layer. The introduction of 6,6-phenyl-C61-butyric acid methyl ester reduces this barrier, allowing electrons to more easily cross the interface and transfer to the electron transport layer. A good energy level alignment effect is formed to promote the separation of photogenerated electrons and holes. When 6,6-phenyl-C61-butyric acid methyl ester optimizes the energy level alignment at the interface of tin iodide and cesium tin iodide, the photogenerated electrons and holes can be more effectively separated and transferred to the electron transport layer and the hole transport layer respectively. The electron-hole pair recombination occurring at the interface is one of the main causes of energy loss. Through energy level alignment, 6,6-phenyl-C61-butyric acid methyl ester reduces the occurrence of this recombination, thereby retaining more photogenerated charges for generating electrical energy.

[0042] Since the 6,6-phenyl-C61-butyric acid methyl ester molecule has an electric dipole moment, the positive and negative charge centers inside the molecule do not overlap, thus forming a tiny electric field. When 6,6-phenyl-C61-butyric acid methyl ester is introduced into a perovskite solar cell, its electric dipole effect affects the built-in electric field. The electric dipole effect of 6,6-phenyl-C61-butyric acid methyl ester can change the interfacial charge distribution between it and the adjacent layers (such as the perovskite layer, the electron transport layer or the hole transport layer). This change in interfacial charge distribution will lead to an increase in the work function difference between the cathode and the anode and between the upper and lower surfaces of the perovskite film. The increase in the work function difference means an increase in the built-in electric field strength.

[0043] The enhanced built-in electric field can form a clearer charge transfer path. Electrons and holes are more easily guided to the correct transfer direction under the action of the built-in electric field, reducing the probability of their collision and recombination during the transmission process. The enhanced built-in electric field increases the charge transmission speed. At the same time, it also reduces the loss of charge during the transmission process, thereby improving the charge collection efficiency.

[0044] S2: The substrate is cleaned by ultrasonic cleaning to remove surface stains, and then rinsed with deionized water and dried. The drying is performed by blowing hot air at a temperature of 80-100° C. for 20-30 minutes.

[0045] It should be noted that in the ultrasonic cleaning chamber, under the action of ultrasonic waves, the microbubbles in the cleaning liquid will keep vibrating, and when the sound pressure or sound intensity reaches a certain level, they will rapidly expand and close, generating shock waves. This shock wave can destroy the adsorption of dirt and the surface of the cleaning object, and cause fatigue damage to the dirt layer and be peeled off, thereby achieving the cleaning effect.

[0046] When cleaning, fully immerse the substrate to be cleaned in the cleaning liquid, and the water level cannot exceed the maximum water level line. Start the ultrasonic cleaning machine. After cleaning, turn off the machine and take out the substrate. Then rinse the cleaned substrate with deionized water to remove the residual cleaning agent and other impurities during the cleaning process, and finally dry it with hot air to make the surface of the substrate dry.

[0047] The precursor solution obtained in S1 is coated on the substrate obtained in S2 by inkjet printing, wherein the inkjet printing accuracy is 10 μm, the speed is 10 m / s, and the droplet size is 5 nL.

[0048] The substrate coated in S3 is dried to remove moisture, and annealed to obtain a perovskite solar cell absorption layer, wherein the drying temperature is 75-85°C and the time is 0.5-1.5h; the annealing temperature is 100-200°C and the time is 20-40min.

[0049] A production device for a perovskite solar cell absorption layer comprises: a workbench, a mobile loading device arranged on the workbench, an inkjet printing device and a drying device,

[0050] As shown in the figure, the production equipment of perovskite solar cells in the present invention includes a workbench, a mobile carrier, an inkjet printing device and a drying device; the mobile carrier is slidably installed on the workbench, and the mobile carrier is used to carry and transport the substrate; the inkjet printing device is installed on the workbench and is arranged above the mobile carrier; the drying device is installed on the workbench and is arranged above the mobile carrier, and along the transportation direction of the substrate, the drying device is located downstream of the inkjet printing device.

[0051] It should be noted that the inkjet printing device uses inkjet printing to place the precursor solution prepared in the above method into the inkjet printing device, prints it on the substrate by inkjet printing, and then performs drying and annealing treatment under the action of the drying device. The solvent in the perovskite organic ink evaporates, and an organic salt layer is formed on the inorganic salt layer. The organic salt reacts with the inorganic salt to crystallize to form a perovskite functional layer (absorption layer). It can be understood that the production equipment of the perovskite solar cell of the present invention forms a functional layer or functional film (such as the above-mentioned organic salt layer) on the substrate by inkjet printing through an inkjet printing device, replacing the existing functional layer preparation device, thereby improving the preparation efficiency of the functional layer, that is, improving the production efficiency of the perovskite solar cell.

[0052] The workbench is provided with a linear motion mechanism, which includes a slide rail, and the mobile carrier is slidably installed on the slide rail; a loading device and a unloading device are also provided on both sides of the mobile carrier.

[0053] As shown in the figure, in this embodiment, the workbench is provided with a linear motion mechanism, the linear motion mechanism includes a slide rail, and the mobile object carrier is slidably mounted on the slide rail. It can be understood that the workbench is provided with an interactive linear motion mechanism, and the slide rail plays a role in limiting the movement direction of the mobile object carrier.

[0054] Among them, the linear motion mechanism also includes a stepper motor. Each mobile carrier can be connected to a stepper motor to drive the mobile carrier to perform reciprocating linear motion on the slide rail, thereby improving the degree of automation of the entire equipment.

[0055] Preferably, as shown in the figure, a plurality of movable loading devices are slidably connected to the slide rail, and the movable loading device includes a loading seat and a loading mechanism installed on the loading seat, the loading seat is slidably connected to the slide rail, and the loading mechanism is used to carry the substrate.

[0056] It should be noted that since it takes time for the mobile carrier to receive the substrate, transport the substrate to the inkjet printing device and the drying device, and perform inkjet printing and drying, in order to improve the working efficiency of the entire equipment, multiple mobile carriers are slidably connected to the slide rail.

[0057] For example, when a mobile carrier is located below an inkjet printing device to perform inkjet printing, other mobile carriers can simultaneously receive substrates or dry the substrates after inkjet printing.

[0058] Furthermore, the production equipment of perovskite solar cells includes a loading device and a unloading device installed on a workbench, a mobile carrier is arranged between the loading device and the unloading device, and the mobile carrier also includes a lifting mechanism installed on a carrier seat, and the carrier mechanism is installed on the lifting mechanism.

[0059] The loading device and the unloading device are specifically conveyor belts. When loading is required, the loading mechanism of each mobile loading device is horizontally close to the unloading position of the loading device, and then the loading device transports the substrate to the loading mechanism.

[0060] It should be noted that, since a plurality of mobile carriers are slidably connected on a slide rail, when loading, along the transport direction of the substrate, the mobile carrier located upstream can be moved to the bottom of the loading device, and the height of the carrier can be adjusted by the lifting mechanism, so that the mobile carrier located upstream is moved to the bottom of the loading device, and the mobile carrier located downstream is adjusted by the lifting mechanism to be close to and aligned with the unloading place of the loading device in terms of horizontal height, that is, the substrate is preferentially transported to the mobile carrier located downstream, and after the loading of the mobile carrier located downstream is completed, when the subsequent steps are carried out, the mobile carrier located upstream moves to the unloading place of the loading device, and the height of the carrier can be adjusted by the lifting mechanism to achieve loading. In this way, the production and processing efficiency of the equipment is improved through the above process.

[0061] The unloading process is similar to the loading process. The mobile carrier located downstream unloads the materials first and then hides under the unloading device, allowing the mobile carrier located upstream to unload the materials. The lifting mechanism includes a lifting motor and a mounting seat matched therewith. The linear motion mechanism includes two slide rails arranged at intervals, and each slide rail is slidably connected to multiple mobile carriers.

[0062] It should be noted that after all the mobile carriers on a slide rail have finished loading, all the mobile carriers on the slide rail need to finish unloading before a new loading process can be carried out, that is, after the most upstream mobile carrier on the slide rail has finished loading, it is necessary to wait for it to unload before a new loading process can be carried out. Therefore, in order to further improve production efficiency, two slide rails can be set. When all the mobile carriers on one slide rail have finished loading, the mobile carrier on the other slide rail can load; or the mobile carriers on the two slide rails load alternately, and two sets of conveyor belts are respectively provided on the loading device and the unloading device, corresponding to each slide rail.

[0063] A mobile loading device is slidably mounted on the workbench, and the mobile loading device is used to carry and transport the substrate;

[0064] In a preferred embodiment of the present invention, the mobile loading device includes a loading seat and a loading mechanism, the loading seat is slidably connected to the slide rail, a base is arranged on the loading mechanism, a lifting mechanism is arranged on the loading seat, a horizontal moving mechanism is arranged on the lifting mechanism, and the loading mechanism is installed on the horizontal moving mechanism.

[0065] In a preferred embodiment of the present invention, the carrying mechanism includes a paper roll transmission belt, which is used to carry and transport the substrate. A vacuum absorber is provided below the paper roll transmission belt, which is used to absorb the substrate onto the paper roll transmission belt.

[0066] An inkjet printing device is installed on the workbench and is arranged above the moving loading device;

[0067] The drying device is installed on the workbench and arranged above the moving object carrier. Along the transport direction of the substrate, the drying device is located downstream of the inkjet printing device.

[0068] It should be noted that the movable loading device also includes a horizontal moving mechanism installed on the lifting mechanism, and the loading mechanism is installed on the horizontal moving mechanism. The linear motion mechanism includes two slide rails arranged at intervals, so that the horizontal moving mechanism can move the loading mechanism in the horizontal direction to just below the inkjet printing device.

[0069] The production equipment of the perovskite solar cell in the present invention includes an image detection device installed on a workbench, facing the transportation direction of the substrate, and the image detection device is located upstream of the inkjet printing device, and is used to capture the image of the substrate on the mobile carrier. The image detection device can capture the image of the substrate carried on the carrier mechanism of the mobile carrier, which can be used to confirm whether the carrier mechanism carries a substrate, and avoid the inkjet printing device spraying ink on the carrier mechanism that does not carry the substrate, thereby contaminating the carrier mechanism.

[0070] Furthermore, the mobile object carrier also includes a horizontal rotation mechanism installed on the lifting mechanism, and the object carrier is installed on the horizontal rotation mechanism. That is, the image detection device can capture the image of the substrate carried by the object carrier of the mobile object carrier, and can also be used to determine the placement angle of the substrate. Once the placement angle of the substrate is incorrect, the horizontal rotation mechanism can control the object carrier to rotate in the horizontal plane, so as to rotate the substrate on the object carrier to the correct or required placement angle (i.e., correct the position of the substrate), which is convenient for the subsequent inkjet printing device. The horizontal rotation mechanism includes a drive motor, which can control the rotation of the object carrier.

[0071] In an embodiment, the loading mechanism includes a paper roll transmission belt, which is used to carry and transport the substrate. The loading mechanism also includes a loading drive assembly for driving the paper roll transmission belt. The paper roll transmission belt serves to move the substrate to the center position of the loading mechanism to prevent the substrate from falling when the mobile loading device moves.

[0072] During operation, the carrying mechanism includes two spaced motorized rollers, the two ends of the paper roll transmission belt are respectively wound around the two motorized rollers, and the substrate on the paper roll transmission belt is moved by the rotation of the two spaced motorized rollers. The carrying mechanism also includes a vacuum absorber, which is arranged below the paper roll transmission belt and is used to absorb the substrate on the paper roll transmission belt. This arrangement can ensure that when the horizontal rotation mechanism rotates, the substrate can rotate synchronously at the same angle.

[0073] Embodiment 1:

[0074] Formamidine tin iodide, cesium tin iodide and 6,6-phenyl-C61-butyric acid methyl ester are mixed as a precursor mixture in a molar ratio of 1:1:0.5, and a mixed solution of dimethyl sulfoxide and dimethylformamide in a ratio of 1:1 is added, and 2 L of the solvent is added to the precursor mixture in a ratio of 1 mol to the solvent, and the stirring temperature is 60° C. and the stirring time is 2 h to obtain a precursor solution;

[0075] The substrate was cleaned with ultrasonic waves to remove surface stains, then rinsed with deionized water and dried. The drying was performed by blowing hot air at a temperature of 90° C. for 25 minutes.

[0076] The precursor solution was coated on the substrate obtained in S2 by inkjet printing, with an inkjet printing accuracy of 10 μm, a speed of 10 m / s, and a droplet size of 5 nL.

[0077] The coated substrate was dried at 80°C for 1 hour to remove moisture, and then annealed at 150°C for 30 minutes to obtain a perovskite solar cell absorption layer.

[0078] Experiment 1:

[0079] The preparation method of Example 1 was used as an experimental group, and the molar ratio of formamidine tin iodide, cesium tin iodide and 6,6-phenyl-C61-butyric acid methyl ester in the precursor mixture of the experimental group, the stirring temperature and the inkjet printing speed were changed on the basis of Example 1 to prepare the products respectively. The prepared products were used as several control groups. The experimental group and the control group were placed at an ambient temperature of 25°C and used 1000W / m 2The light intensity is measured, and the AM 1.5G spectrum distribution is used to simulate the actual irradiation of sunlight on the earth. Different voltages are applied to the control group and the experimental group to obtain the JV curve. The open circuit voltage (VOC), short circuit current density (JSC) and maximum power point (MPP) are read from the JV curve to calculate the PCE value (photoelectric conversion efficiency) of the battery. PCE = (Pmax) / (Pin) × 100% is used to calculate the photoelectric conversion efficiency, where Pmax is the output power at the maximum power point, obtained by multiplying Vmax and Jmax (Pmax = Vmax × Jmax), and Pin is the incident light power, which is 1000W / m under standard test conditions. 2 Since Pmax can also be expressed as the ratio of the product of VOC, JSC and fill factor FF to the incident light power Pin (ie PCE = (VOC × JSC × FF) / Pin), the PCE value can also be calculated by this formula, as shown in Table 1.

[0080] Table 1

[0081]

[0082]

[0083] As can be seen from Table 1, in the precision preparation process of perovskite solar cells, the interaction between the concentration of 6,6-phenyl-C61-butyric acid methyl ester, stirring temperature and inkjet printing speed constitutes an intricate network, which has a profound and subtle impact on the photoelectric conversion efficiency (PCE) of the battery.

[0084] First, 6,6-phenyl-C61-butyric acid methyl ester is a key component of the electron transport layer. Excessive concentration of 6,6-phenyl-C61-butyric acid methyl ester will cause particles to form agglomerates in the perovskite layer. These agglomerates will become obstacles to electron transport, increase the probability of electron scattering and recombination during the transmission process, and thus significantly reduce the electron transmission efficiency of the battery. At the same time, high concentrations of PC61BM can also interfere with the normal growth of perovskite crystals, resulting in an increase in crystal defects and a decrease in crystal quality. On the contrary, if the concentration of PC61BM is too low, it will not be able to form an effective dipole layer between the perovskite layer and the electron transport layer, which will affect the energy level alignment between the two, making it difficult for electrons to be transmitted at the interface, which will also reduce the PCE of the battery.

[0085] However, the distribution uniformity of 6,6-phenyl-C61-butyric acid methyl ester in the perovskite layer is not only affected by the concentration, but also regulated by the stirring temperature. If the stirring temperature is too high, the volatilization of the solvent will accelerate, resulting in uneven distribution of the components in the solution, making the distribution of 6,6-phenyl-C61-butyric acid methyl ester in the perovskite layer also uneven. This unevenness will further aggravate the obstacles to electron transport and reduce the electron transport performance of the battery. At the same time, high-temperature stirring may also cause decomposition or phase change of the perovskite precursor, causing irreversible damage to the performance of the battery. On the contrary, if the stirring temperature is too low, the volatilization rate of the solvent will slow down, resulting in insufficient mixing of the components in the solution, which will not only affect the uniformity of the distribution of 6,6-phenyl-C61-butyric acid methyl ester in the perovskite layer, but also slow down the growth rate of perovskite crystals, prolong the preparation time, and increase the preparation cost.

[0086] In addition, the inkjet printing speed also affects the PCE of the battery. Printing too fast will shorten the evaporation time of the solvent on the substrate, resulting in incomplete crystallization of the perovskite particles and the formation of more holes and defects. These defects will become the recombination center of electrons and holes, reducing the photoelectric conversion efficiency of the battery. At the same time, too fast a printing speed can also make the distribution of 6,6-phenyl-C61-butyric acid methyl ester in the perovskite layer more uneven, further exacerbating the obstacles to electron transport. On the contrary, if the printing speed is too slow, the evaporation time of the solvent on the substrate will be too long, resulting in excessive growth of perovskite particles or the formation of larger grains, which will affect the uniformity and crystallization quality of the film, and also reduce the PCE of the battery.

[0087] In summary, the interaction between the concentration of PC61BM, stirring temperature and inkjet printing speed constitutes a complex network, which jointly affects the photoelectric conversion efficiency of perovskite solar cells. In order to obtain high-performance perovskite solar cells, ensure the uniform distribution of PC61BM in the perovskite layer, optimize the crystallization quality and energy level alignment, and control the uniformity and thickness of the film. Only in this way can the photoelectric conversion potential of perovskite solar cells be fully utilized and efficient and stable energy conversion be achieved. Among them, the optimal molar ratio of formamidinium tin iodide, cesium tin iodide and 6,6-phenyl-C61-butyric acid methyl ester is 1:1:0.5, the optimal stirring temperature is 60°C, and the optimal inkjet printing speed is 10m / s.

[0088] The above is based on the ideal embodiment of the present invention. Through the above description, relevant personnel can make various changes and modifications without departing from the technical concept of the present invention. The technical scope of the present invention is not limited to the content in the specification, and the technical scope must be determined according to the scope of the claims.

Claims

1. A method for preparing an absorption layer of a perovskite solar cell, characterized in that: The following steps are involved: S1: Formamidine tin iodide, cesium tin iodide and 6,6-phenyl-C61-butyric acid methyl ester are used as a precursor mixture, a solvent is added, and the mixture is stirred to obtain a precursor solution; S2: The substrate is cleaned by ultrasonic cleaning to remove surface stains, then rinsed with deionized water and dried; S3: coating the precursor solution obtained in S1 on the substrate obtained in S2 by inkjet printing; S4: drying the substrate coated in S3 to remove moisture, and annealing the substrate to obtain a perovskite solar cell absorption layer.

2. The method for preparing a perovskite solar cell absorption layer according to claim 1, characterized in that: In the S1, the molar ratio of formamidine tin iodide, cesium tin iodide and 6,6-phenyl-C61-butyric acid methyl ester is 1:1:0.3-1, the stirring parameters are 300-500r / min, the stirring temperature is 55-65°C, and the stirring time is 1-2.5h.

3. The method for preparing a perovskite solar cell absorption layer according to claim 1, characterized in that: In S1, the solvent is selected from one or a mixture of dimethyl sulfoxide, dimethylformamide, dimethylacetamide or N-methylpyrrolidone, and the ratio of the precursor mixture to the solvent is 1 mol of the precursor mixture and 1.5-2.5 L of the solvent is added.

4. The method for preparing a perovskite solar cell absorption layer according to claim 1, characterized in that: In S2, drying is performed by blowing hot air, the hot air temperature is 80-100°C, and the time is 20-30 minutes.

5. The method for preparing a perovskite solar cell absorption layer according to claim 1, characterized in that: In the S3, the inkjet printing accuracy is 8-11 μm, the speed is 9-11 m / s, and the droplet size is 2-8 nL.

6. The method for preparing a perovskite solar cell absorption layer according to claim 1, characterized in that: In the step S4, the drying temperature is 75-85°C for 0.5-1.5 hours; the annealing temperature is 100-200°C for 20-40 minutes.

7. A production device for a perovskite solar cell absorption layer, based on the absorption layer preparation method of claims 1-6, comprising: A workbench, a mobile loading device, an inkjet printing device and a drying device arranged on the workbench, characterized in that: A mobile loading device, slidably mounted on the workbench, and used for loading and transporting a substrate; An inkjet printing device, mounted on the workbench and arranged above the mobile loading device; The drying device is installed on the workbench and arranged above the movable loading device. Along the transport direction of the substrate, the drying device is located downstream of the inkjet printing device.

8. The production equipment of the perovskite solar cell absorption layer according to claim 7, characterized in that: The workbench is provided with a linear motion mechanism, which includes a slide rail, and the mobile carrier is slidably mounted on the slide rail; a loading device and a unloading device are also provided on both sides of the mobile carrier.

9. The production equipment of the perovskite solar cell absorption layer according to claim 8, characterized in that: The mobile loading device includes a loading seat and a loading mechanism, wherein the loading seat is slidably connected to the slide rail, a base is arranged on the loading mechanism, a lifting mechanism is arranged on the loading seat, a horizontal moving mechanism is arranged on the lifting mechanism, and the loading mechanism is installed on the horizontal moving mechanism.

10. The production equipment of the perovskite solar cell absorption layer according to claim 9, characterized in that: The object-carrying mechanism comprises a paper roll transmission belt, and the paper roll transmission belt is used for carrying and transporting the substrate. A vacuum absorber is arranged below the paper roll transmission belt, and the vacuum absorber is used for adsorbing the substrate on the paper roll transmission belt.

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