Blade coating method preparation method and device of perovskite thin film and perovskite thin film

Abstract

The invention discloses a blade coating preparation method and device of a perovskite thin film and the perovskite thin film, and the method comprises the steps: S100, weighing PbI2 and MAI in a fuming cupboard, dissolving the PbI2 and MAI with GBL to obtain an MAPbI3 solution, and carrying out ball milling on a ball mill to obtain an initial suspension; s200, adding the initial turbid liquid into a PE pipe, then adding magneton and MAI, stirring and heating, and adding PAN when rapid sedimentation begins to obtain a blade coating precursor turbid liquid; s300, pouring the blade coating precursor suspension on one side of a substrate for blade coating, placing the substrate on a heating stage, and covering the substrate with a semi-closed glass cover; s400, adding a GBL and DMF mixed solvent into the bubbler, heating in a water bath, introducing high-purity nitrogen, and introducing the nitrogen carrying the mixed solvent into the glass cover; and S500, removing the perovskite in the electrode area of the pixelated substrate by using a scraper, so that the thermally evaporated metal electrode is exposed in the electrode area. A precise blade coating process is matched with dynamic solvent annealing, and a polymer is added to regulate and control the rheological property of the turbid liquid, so that a spin-coating precursor solution with high stability is obtained.

Description

Technical Field

[0001] This invention belongs to the field of perovskite thin film technology, and more specifically, relates to a method, apparatus and perovskite thin film preparation method of perovskite thin film by blade coating. Background Technology

[0002] As a core component in medical imaging, industrial non-destructive testing, and biomedical applications, X-ray flat panel detectors, with their key performance parameters such as sensitivity, spatial resolution, and signal-to-noise ratio, directly limit the diagnostic accuracy and detection limits of imaging systems. In recent years, metal halide perovskites, with their superior photoelectric physical properties—including high X-ray absorption coefficient, high carrier mobility-lifetime product, tunable bandgap, and low defect state density—have been recognized as key semiconductor materials for constructing next-generation high-resolution, low-dose direct-conversion X-ray detectors.

[0003] Among numerous fabrication technologies, blade coating, as a solution processing technique, is considered a key candidate for large-scale production and commercial application of perovskite optoelectronic devices due to its significant potential in low cost, large-area fabrication, excellent scalability, and continuous roll-to-roll production. However, compared to the precise film formation control exhibited by spin coating on small-area substrates, blade coating still faces a series of unresolved process bottlenecks in fabricating large-area, high-crystallinity, and uniformly dense perovskite thick films.

[0004] First, controlling the crystallization kinetics of thin films is a core challenge. The solvent engineering and rheological properties of the precursor solution are decisive factors determining the final film morphology, defect state density, and photoelectric performance. Perovskite precursor solutions typically rely on high-boiling-point solvents, and their slow and non-uniform evaporation process makes precise control of crystallization kinetics difficult. To address this issue, Jiang Tang's team reported a synergistic rheological engineering strategy. By adding polyacrylonitrile and excess methylammonium iodide to precisely control the viscoelasticity of the perovskite suspension, they successfully constructed a high-sensitivity, low-noise X-ray flat panel detector with a spatial resolution as high as 0.51 lp / pixel, approaching the Nyquist limit determined by pixel size. Furthermore, the viscosity and surface tension of the precursor solution are highly sensitive to process parameters such as ambient temperature and humidity. Such fluctuations can easily lead to uncontrolled wetting and spreading behavior of the liquid film during the coating process, thus severely restricting the process repeatability and batch consistency of device fabrication. Summary of the Invention

[0005] To address the aforementioned deficiencies or improvement needs of existing technologies, this invention provides a method, apparatus, and perovskite thin film preparation via a spin coating process. It employs a precision spin coating process combined with dynamic solvent annealing technology. By adding polymers to regulate the rheological properties of the suspension, a highly stable spin coating precursor solution is obtained, significantly reducing sedimentation, improving film thickness uniformity, and reducing the surface roughness of the perovskite thin film on large-area substrates. This significantly improves the preparation efficiency compared to traditional spin coating methods. Simultaneously, the invention explores the optimization of parameters such as spin coating speed and solvent concentration in the spin coating process. Combined with dynamic solvent annealing technology, the film undergoes a controllable solvation-desolventization recrystallization process in a solvent vapor environment, further eliminating localized shrinkage lines and further improving the uniformity and quality of large-area films.

[0006] To achieve the above objectives, according to a first aspect of the present invention, a method for preparing perovskite thin films by a blade coating method is provided, specifically including the following steps: S100. Weigh PbI2 and MAI in a fume hood, dissolve them in GBL to obtain MAPbI3 solution, add MAPbI3 solution to a ball mill jar, put in small grinding balls, and ball mill on a ball mill to obtain initial suspension. S200. Take the initial suspension and add it to the PE tube, then add the magnetic spool and MAI, stir and heat, and observe the color and fluidity of the suspension at the same time. When the suspension begins to settle rapidly, add PAN and continue stirring to obtain the coating precursor suspension. S300. Prepare a pixelated substrate with ITO, pour the coating precursor suspension onto one side of the substrate, and coat it with a blade coating device. Place the freshly coated film on a hot table and cover it with a semi-enclosed glass cover with ventilation holes. S400. Add a mixture of GBL and DMF solvents to the bubbler, place the bubbler in a water bath and heat it, and introduce high-purity nitrogen gas. Then, introduce the nitrogen gas carrying the mixed solvent into the glass cover and blow it parallel to the sample surface along the coating direction. S500: Use a scraper to remove the perovskite from the pixelated substrate electrode area, exposing the electrode area to thermally evaporated metal electrodes.

[0007] Furthermore, in step S100, the solute concentration of the MAPbI3 solution obtained by dissolving in GBL is 4-4.5 mol / L.

[0008] Further, in step S100, the mass of the small grinding ball is 100-1000mg, the rotation speed of the ball mill is 800-1000rpm, and the grinding time is 6-10h.

[0009] Further, in step S200, the initial suspension added to the PE tube is 2 ml, the mass of MAI added is 60 mg, and after adding the magnetic ball and MAI, it is necessary to stir and heat at 80-90℃ and 1600 rpm for 6-10 h.

[0010] Further, in step S200, when the suspension is precipitated, 60 mg of PAN is added. After adding PAN, the mixture is stirred for 30 min until the viscosity of the suspension, measured by a rotational viscometer at 30 rpm, reaches 900-1000 mPa·s.

[0011] Furthermore, in step S300, the pixelated substrate has a size of 400mm×400mm and is cleaned using plasma or ultraviolet-ozone treatment. In step S300, 10 ml of the precursor suspension is poured onto the pixelated substrate and the coating speed is 0.6-0.8 m / s.

[0012] Further, in step S400, the volume of the mixed solvent of GBL and DMF added to the bubbler is 30-40 ml, and the mixing ratio of GBL and DMF in the mixed solution is 5:1-3:1.

[0013] Furthermore, in step S400, the water bath heating temperature is 60-80℃, and the flow rate of high-purity nitrogen is controlled at 250-300 sccm. When nitrogen is introduced, the initial temperature of the heating stage is set to 80-85℃. The film is heated continuously for 2-3 hours. Then the gas supply is turned off, and the temperature of the heating stage is adjusted to 100℃. The film is heated continuously for 7-8 hours.

[0014] According to a second aspect of the present invention, a blade coating apparatus for preparing perovskite thin films is provided, comprising: a pixelated substrate; The pixelated substrate is covered with an ITO carrier transport layer. A perovskite layer and a metal electrode layer are formed on the surface of the ITO carrier transport layer. The metal electrode layer is located on one side of the ITO carrier transport layer, and a metal electrode layer is also provided on the surface of the perovskite layer.

[0015] According to a third aspect of the present invention, a perovskite thin film is provided, which is prepared by a blade coating method for perovskite thin films.

[0016] In summary, compared with the prior art, the above-described technical solutions conceived by this invention can achieve the following beneficial effects: 1. The perovskite thin film preparation method of the present invention adopts a precision coating process combined with dynamic solvent annealing technology. By adding polymers to regulate the rheological properties of the suspension, a highly stable spin-coating precursor solution is obtained, which significantly reduces sedimentation, improves the uniformity of film thickness, and reduces the surface roughness of perovskite thin films on large-area substrates. The preparation efficiency is greatly improved compared with the traditional spin-coating method.

[0017] 2. The perovskite thin film preparation method of the present invention explores the optimization of parameters such as coating speed and solvent concentration in the coating process. Combined with dynamic solvent annealing technology, the film layer undergoes a controllable solvation-desolventization recrystallization process in a solvent vapor environment, which further eliminates local shrinkage lines and further improves the uniformity and quality of large-area films. Attached Figure Description

[0018] Figure 1 This is a schematic flowchart of a method for preparing a perovskite thin film by a blade coating according to an embodiment of the present invention; Figure 2 This is a schematic diagram illustrating a method for preparing a perovskite thin film by a blade coating according to an embodiment of the present invention; Figure 3 This is a schematic diagram of the structure of a perovskite thin film according to an embodiment of the present invention; Figure 4 This is a surface SEM schematic diagram of a perovskite thin film according to an embodiment of the present invention; Figure 5 This is a cross-sectional SEM schematic diagram of a perovskite thin film according to an embodiment of the present invention; Figure 6 This is a schematic diagram of the It curve performance of a perovskite thin film according to an embodiment of the present invention; Figure 7 This is an XRD diagram of a perovskite thin film according to an embodiment of the present invention.

[0019] In all the accompanying drawings, the same reference numerals denote the same technical features, specifically: 1-pixelated substrate, 2-ITO carrier transport layer, 3-perovskite layer, 4-metal electrode layer. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0021] Example 1 like Figure 1 , 2As shown, this embodiment of the invention provides a method for preparing perovskite thin films by a blade coating method, specifically including the following steps: S100. Weigh PbI2 and MAI in a fume hood, dissolve them in GBL to obtain MAPbI3 solution, add MAPbI3 solution to a ball mill jar, put in small grinding balls, and ball mill on a ball mill to obtain initial suspension. S200. Take the initial suspension and add it to the PE tube, then add the magnetic spool and MAI, stir and heat, and observe the color and fluidity of the suspension at the same time. When the suspension begins to settle rapidly, add PAN and continue stirring to obtain the coating precursor suspension. S300. Prepare a pixelated substrate with ITO, pour the coating precursor suspension onto one side of the substrate, and coat it with a blade coating device. Place the freshly coated film on a hot table and cover it with a semi-enclosed glass cover with ventilation holes. S400. Add a mixture of GBL and DMF solvents to the bubbler, place the bubbler in a water bath and heat it, and introduce high-purity nitrogen gas. Then, introduce the nitrogen gas carrying the mixed solvent into the glass cover and blow it parallel to the sample surface along the coating direction. S500: Use a scraper to remove the perovskite from the pixelated substrate electrode area, exposing the electrode area to thermally evaporated metal electrodes.

[0022] In step S100, the solute concentration of the MAPbI3 solution obtained by dissolving GBL is 4 mol / L.

[0023] In step S100, the mass of the small grinding ball is 100mg, the rotation speed of the ball mill is 800rpm, and the grinding time is 6h.

[0024] In step S200, 2 ml of the initial suspension is added to the PE tube, and 60 mg of MAI is added. After adding the magnetic flux and MAI, the mixture is stirred and heated for 6 hours at 80°C and 1600 rpm.

[0025] In step S200, during the precipitation of the suspension, 60 mg of PAN is added. After adding PAN, the mixture is stirred for 30 min until the viscosity of the suspension reaches 900 mPa·s as measured by a rotational viscometer at 30 rpm.

[0026] In step S300, the pixelated substrate has a size of 400mm×400mm and is cleaned using plasma or ultraviolet-ozone treatment.

[0027] In step S300, 10 ml of the precursor suspension is poured onto the pixelated substrate and the coating speed is 0.6 m / s.

[0028] In step S400, the volume of the GBL and DMF mixed solvent added to the bubbler is 30 ml, and the mixing ratio of GBL and DMF in the mixed solution is 5:1.

[0029] In step S400, the water bath heating temperature is 60°C, and the flow rate of high-purity nitrogen is controlled at 250 sccm.

[0030] In step S400, when nitrogen gas is introduced, the initial temperature of the hot stage is set to 80°C, and the film is continuously heated for 2 hours. Then the gas supply is turned off, and the temperature of the hot stage is adjusted to 100°C, and the film is continuously heated for 7 hours.

[0031] In step S500, the material of the metal electrode is Au, and its thickness is 80 nm.

[0032] A precision spin-coating process combined with dynamic solvent annealing technology was employed. By adding polymers to regulate the rheological properties of the suspension, a highly stable spin-coating precursor solution was obtained, significantly reducing sedimentation, improving film thickness uniformity, and reducing the surface roughness of perovskite films on large-area substrates. This resulted in a significant improvement in preparation efficiency compared to traditional spin-coating methods. Simultaneously, optimization of parameters such as spin-coating speed and solvent concentration in the process was explored. Combined with dynamic solvent annealing, the film underwent a controllable solvation-desolventization recrystallization process in a solvent vapor environment, further eliminating localized shrinkage lines and further improving the uniformity and quality of large-area films.

[0033] Example 2 This invention provides a method for preparing perovskite thin films by a blade coating process, specifically including the following steps: S100. Weigh PbI2 and MAI in a fume hood, dissolve them in GBL to obtain MAPbI3 solution, add MAPbI3 solution to a ball mill jar, put in small grinding balls, and ball mill on a ball mill to obtain initial suspension. S200. Take the initial suspension and add it to the PE tube, then add the magnetic spool and MAI, stir and heat, and observe the color and fluidity of the suspension at the same time. When the suspension begins to settle rapidly, add PAN and continue stirring to obtain the coating precursor suspension. S300. Prepare a pixelated substrate with ITO, pour the coating precursor suspension onto one side of the substrate, and coat it with a blade coating device. Place the freshly coated film on a hot table and cover it with a semi-enclosed glass cover with ventilation holes. S400. Add a mixture of GBL and DMF solvents to the bubbler, place the bubbler in a water bath and heat it, and introduce high-purity nitrogen gas. Then, introduce the nitrogen gas carrying the mixed solvent into the glass cover and blow it parallel to the sample surface along the coating direction. S500: Use a scraper to remove the perovskite from the pixelated substrate electrode area, exposing the electrode area to thermally evaporated metal electrodes.

[0034] In step S100, the solute concentration of the MAPbI3 solution obtained by dissolving in GBL is 4.5 mol / L.

[0035] In step S100, the mass of the small grinding ball is 1000 mg, the rotation speed of the ball mill is 1000 rpm, and the grinding time is 10 h.

[0036] In step S200, 2 ml of the initial suspension is added to the PE tube, and 60 mg of MAI is added. After adding the magnetic flux and MAI, the mixture is stirred and heated for 10 hours at 90°C and 1600 rpm.

[0037] In step S200, during the precipitation of the suspension, 60 mg of PAN is added. After adding PAN, the mixture is stirred for 30 min until the viscosity of the suspension reaches 1000 mPa·s as measured by a rotational viscometer at 30 rpm.

[0038] In step S300, the pixelated substrate has a size of 400mm×400mm and is cleaned using plasma or ultraviolet-ozone treatment.

[0039] In step S300, 10 ml of the precursor suspension is poured onto the pixelated substrate and the coating speed is 0.8 m / s.

[0040] In step S400, the volume of the mixed solvent of GBL and DMF added to the bubbler is 40 ml, and the mixing ratio of GBL and DMF in the mixed solution is 3:1.

[0041] In step S400, the water bath heating temperature is 80℃, and the flow rate of high-purity nitrogen is controlled at 300 sccm.

[0042] In step S400, when nitrogen gas is introduced, the initial temperature of the hot stage is set to 85°C, and the film is continuously heated for 3 hours. Then the gas supply is turned off, and the temperature of the hot stage is adjusted to 100°C, and the film is continuously heated for 8 hours.

[0043] In step S500, the material of the metal electrode is Au, and its thickness is 100 nm.

[0044] Example 3 This invention provides a method for preparing perovskite thin films by a blade coating process, specifically including the following steps: S100. Weigh PbI2 and MAI in a fume hood, dissolve them in GBL to obtain MAPbI3 solution, add MAPbI3 solution to a ball mill jar, put in small grinding balls, and ball mill on a ball mill to obtain initial suspension. S200. Take the initial suspension and add it to the PE tube, then add the magnetic MAI, stir and heat, while observing the color and fluidity of the suspension. When the suspension begins to settle rapidly, add PAN and continue stirring to obtain the coating precursor suspension. S300. Prepare a pixelated substrate with ITO, pour the coating precursor suspension onto one side of the substrate, and coat it with a blade coating device. Place the freshly coated film on a hot table and cover it with a semi-enclosed glass cover with ventilation holes. S400. Add a mixture of GBL and DMF solvents to the bubbler, place the bubbler in a water bath and heat it, and introduce high-purity nitrogen gas. Then, introduce the nitrogen gas carrying the mixed solvent into the glass cover and blow it parallel to the sample surface along the coating direction. S500: Use a scraper to remove the perovskite from the pixelated substrate electrode area, exposing the electrode area to thermally evaporated metal electrodes.

[0045] In step S100, the solute concentration of the MAPbI3 solution obtained by dissolving in GBL is 4.5 mol / L.

[0046] In step S100, the mass of the small grinding ball is 500 mg, the rotation speed of the ball mill is 900 rpm, and the grinding time is 8 h.

[0047] In step S200, 2 ml of the initial suspension is added to the PE tube, and 60 mg of MAI is added. After adding the magnetic flux and MAI, the mixture is stirred and heated for 8 hours at 85°C and 1600 rpm.

[0048] In step S200, during the precipitation of the suspension, 60 mg of PAN is added. After adding PAN, the mixture is stirred for 30 min until the viscosity of the suspension reaches 950 mPa·s as measured by a rotational viscometer at 30 rpm.

[0049] In step S300, the pixelated substrate has a size of 400mm×400mm and is cleaned using plasma or ultraviolet-ozone treatment.

[0050] In step S300, 10 ml of the precursor suspension is poured onto the pixelated substrate and the coating speed is 0.7 m / s.

[0051] In step S400, the volume of the mixed solvent of GBL and DMF added to the bubbler is 35 ml, and the mixing ratio of GBL and DMF in the mixed solution is 4:1.

[0052] In step S400, the water bath heating temperature is 70°C, and the flow rate of high-purity nitrogen is controlled at 275 sccm.

[0053] In step S400, when nitrogen gas is introduced, the initial temperature of the hot stage is set to 85°C, and the film is continuously heated for 3 hours. Then the gas supply is turned off, and the temperature of the hot stage is adjusted to 100°C, and the film is continuously heated for 8 hours.

[0054] In step S500, the metal electrode is made of Au and has a thickness of 90 nm.

[0055] Example 4 This invention provides a method for preparing perovskite thin films by a blade coating process, specifically including the following steps: S100. Weigh PbI2 and MAI in a fume hood, dissolve them in GBL to obtain MAPbI3 solution, add MAPbI3 solution to a ball mill jar, put in small grinding balls, and ball mill on a ball mill to obtain initial suspension. S200. Take the initial suspension and add it to the PE tube, then add the magnetic MAI, stir and heat, while observing the color and fluidity of the suspension. When the suspension begins to settle rapidly, add PAN and continue stirring to obtain the coating precursor suspension. S300. Prepare a pixelated substrate with ITO, pour the coating precursor suspension onto one side of the substrate, and coat it with a blade coating device. Place the freshly coated film on a hot table and cover it with a semi-enclosed glass cover with ventilation holes. S400. Add a mixture of GBL and DMF solvents to the bubbler, place the bubbler in a water bath and heat it, and introduce high-purity nitrogen gas. Then, introduce the nitrogen gas carrying the mixed solvent into the glass cover and blow it parallel to the sample surface along the coating direction. S500: Use a scraper to remove the perovskite from the pixelated substrate electrode area, exposing the electrode area to thermally evaporated metal electrodes.

[0056] In step S100, the solute concentration of the MAPbI3 solution obtained by dissolving GBL is 4 mol / L.

[0057] In step S100, the mass of the small grinding ball is 1000 mg, the rotation speed of the ball mill is 1000 rpm, and the grinding time is 6 h.

[0058] In step S200, 2 ml of the initial suspension is added to the PE tube, and 60 mg of MAI is added. After adding the magnetic flux and MAI, the mixture is stirred and heated for 8 hours at 85°C and 1600 rpm.

[0059] In step S200, during the precipitation of the suspension, 60 mg of PAN is added. After adding PAN, the mixture is stirred for 30 min until the viscosity of the suspension reaches 1000 mPa·s as measured by a rotational viscometer at 30 rpm.

[0060] In step S300, the pixelated substrate has a size of 400mm×400mm and is cleaned using plasma or ultraviolet-ozone treatment.

[0061] In step S300, 10 ml of the precursor suspension is poured onto the pixelated substrate and the coating speed is 0.8 m / s.

[0062] In step S400, the volume of the mixed solvent of GBL and DMF added to the bubbler is 35 ml, and the mixing ratio of GBL and DMF in the mixed solution is 5:1.

[0063] In step S400, the water bath heating temperature is 80℃, and the flow rate of high-purity nitrogen is controlled at 250 sccm.

[0064] In step S400, when nitrogen gas is introduced, the initial temperature of the hot stage is set to 80°C, and the film is continuously heated for 3 hours. Then the gas supply is turned off, and the temperature of the hot stage is adjusted to 100°C, and the film is continuously heated for 8 hours.

[0065] In step S500, the material of the metal electrode is Au, and its thickness is 100 nm.

[0066] Example 5 This invention provides a method for preparing perovskite thin films by a blade coating process, specifically including the following steps: S100. Weigh PbI2 and MAI in a fume hood, dissolve them in GBL to obtain MAPbI3 solution, add MAPbI3 solution to a ball mill jar, put in small grinding balls, and ball mill on a ball mill to obtain initial suspension. S200. Take the initial suspension and add it to the PE tube, then add the magnetic MAI, stir and heat, while observing the color and fluidity of the suspension. When the suspension begins to settle rapidly, add PAN and continue stirring to obtain the coating precursor suspension. S300. Prepare a pixelated substrate with ITO, pour the coating precursor suspension onto one side of the substrate, and coat it with a blade coating device. Place the freshly coated film on a hot table and cover it with a semi-enclosed glass cover with ventilation holes. S400. Add a mixture of GBL and DMF solvents to the bubbler, place the bubbler in a water bath and heat it, and introduce high-purity nitrogen gas. Then, introduce the nitrogen gas carrying the mixed solvent into the glass cover and blow it parallel to the sample surface along the coating direction. S500: Use a scraper to remove the perovskite from the pixelated substrate electrode area, exposing the electrode area to thermally evaporated metal electrodes.

[0067] In step S100, the solute concentration of the MAPbI3 solution obtained by dissolving GBL is 4 mol / L.

[0068] In step S100, the mass of the small grinding ball is 250 mg, the rotation speed of the ball mill is 9000 rpm, and the grinding time is 7 h.

[0069] In step S200, 2 ml of the initial suspension is added to the PE tube, and 60 mg of MAI is added. After adding the magnetic flux and MAI, the mixture is stirred and heated for 9 hours at 80°C and 1600 rpm.

[0070] In step S200, during the precipitation of the suspension, 60 mg of PAN is added. After adding PAN, the mixture is stirred for 30 min until the viscosity of the suspension reaches 1000 mPa·s as measured by a rotational viscometer at 30 rpm.

[0071] In step S300, the pixelated substrate has a size of 400mm×400mm and is cleaned using plasma or ultraviolet-ozone treatment.

[0072] In step S300, 10 ml of the precursor suspension is poured onto the pixelated substrate and the coating speed is 0.6 m / s.

[0073] In step S400, the volume of the mixed solvent of GBL and DMF added to the bubbler is 35 ml, and the mixing ratio of GBL and DMF in the mixed solution is 4:1.

[0074] In step S400, the water bath heating temperature is 80℃, and the flow rate of high-purity nitrogen is controlled at 250 sccm.

[0075] In step S400, when nitrogen gas is introduced, the initial temperature of the hot stage is set to 80°C, and the film is continuously heated for 3 hours. Then the gas supply is turned off, and the temperature of the hot stage is adjusted to 100°C, and the film is continuously heated for 8 hours.

[0076] In step S500, the material of the metal electrode is Au, and its thickness is 100 nm.

[0077] Example 6 This invention provides a method for preparing perovskite thin films by a blade coating process, specifically including the following steps: S100. Weigh PbI2 and MAI in a fume hood, dissolve them in GBL to obtain MAPbI3 solution, add MAPbI3 solution to a ball mill jar, put in small grinding balls, and ball mill on a ball mill to obtain initial suspension. S200. Take the initial suspension and add it to the PE tube, then add the magnetic MAI, stir and heat, while observing the color and fluidity of the suspension. When the suspension begins to settle rapidly, add PAN and continue stirring to obtain the coating precursor suspension. S300. Prepare a pixelated substrate with ITO, pour the coating precursor suspension onto one side of the substrate, and coat it with a blade coating device. Place the freshly coated film on a hot table and cover it with a semi-enclosed glass cover with ventilation holes. S400. Add a mixture of GBL and DMF solvents to the bubbler, place the bubbler in a water bath and heat it, and introduce high-purity nitrogen gas. Then, introduce the nitrogen gas carrying the mixed solvent into the glass cover and blow it parallel to the sample surface along the coating direction. S500: Use a scraper to remove the perovskite from the pixelated substrate electrode area, exposing the electrode area to thermally evaporated metal electrodes.

[0078] In step S100, the solute concentration of the MAPbI3 solution obtained by dissolving GBL is 4 mol / L.

[0079] In step S100, the mass of the small grinding ball is 750 mg, the rotation speed of the ball mill is 9000 rpm, and the grinding time is 9 h.

[0080] In step S200, 2 ml of the initial suspension is added to the PE tube, and 60 mg of MAI is added. After adding the magnetic flux and MAI, the mixture is stirred and heated for 7 hours at 90°C and 1600 rpm.

[0081] In step S200, during the precipitation of the suspension, 60 mg of PAN is added. After adding PAN, the mixture is stirred for 30 min until the viscosity of the suspension reaches 1000 mPa·s as measured by a rotational viscometer at 30 rpm.

[0082] In step S300, the pixelated substrate has a size of 400mm×400mm and is cleaned using plasma or ultraviolet-ozone treatment.

[0083] In step S300, 10 ml of the precursor suspension is poured onto the pixelated substrate and the coating speed is 0.6 m / s.

[0084] In step S400, the volume of the mixed solvent of GBL and DMF added to the bubbler is 35 ml, and the mixing ratio of GBL and DMF in the mixed solution is 3.5:1.

[0085] In step S400, the water bath heating temperature is 65°C, and the flow rate of high-purity nitrogen is controlled at 280 sccm.

[0086] In step S400, when nitrogen gas is introduced, the initial temperature of the hot stage is set to 82°C, and the film is continuously heated for 2.5 hours. Then the gas supply is turned off, and the temperature of the hot stage is adjusted to 100°C, and the film is continuously heated for 7.5 hours.

[0087] In step S500, the material of the metal electrode is Au, and its thickness is 95 nm.

[0088] Example 7 like Figure 3-7 As shown, this embodiment of the invention provides a blade coating apparatus for preparing perovskite thin films, including a pixelated substrate 1 covered with an ITO carrier transport layer 2. A perovskite layer 3 and a metal electrode layer 4 are formed on the surface of the ITO carrier transport layer 2. The metal electrode layer 4 is located on one side of the ITO carrier transport layer 2, and the surface of the perovskite layer 3 is also provided with a metal electrode layer 4.

[0089] Example 8 This invention provides a perovskite thin film prepared by the blade coating method described in Examples 1-6.

[0090] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for preparing perovskite thin films by blade coating, characterized in that, Specifically, the following steps are included: S100. Weigh PbI2 and MAI in a fume hood, dissolve them in GBL to obtain MAPbI3 solution, add MAPbI3 solution to a ball mill jar, put in small grinding balls, and ball mill on a ball mill to obtain initial suspension. S200. Take the initial suspension and add it to the PE tube, then add the magnetic spool and MAI, stir and heat, and observe the color and fluidity of the suspension at the same time. When the suspension begins to settle rapidly, add PAN and continue stirring to obtain the coating precursor suspension. S300. Prepare a pixelated substrate with ITO, pour the coating precursor suspension onto one side of the substrate, and coat it with a blade coating device. Place the freshly coated film on a hot table and cover it with a semi-enclosed glass cover with ventilation holes. S400. Add a mixture of GBL and DMF solvents to the bubbler, place the bubbler in a water bath and heat it, and introduce high-purity nitrogen gas. Then, introduce the nitrogen gas carrying the mixed solvent into the glass cover and blow it parallel to the sample surface along the coating direction. S500: Use a scraper to remove the perovskite from the pixelated substrate electrode area, exposing the electrode area to thermally evaporated metal electrodes.

2. The method for preparing a perovskite thin film by blade coating according to claim 1, characterized in that, In step S100, the solute concentration of the MAPbI3 solution obtained by dissolving in GBL is 4-4.5 mol / L.

3. The method for preparing a perovskite thin film by blade coating according to claim 2, characterized in that, In step S100, the mass of the small grinding ball is 100-1000mg, the rotation speed of the ball mill is 800-1000rpm, and the grinding time is 6-10h.

4. A method for preparing a perovskite thin film by blade coating according to any one of claims 1-3, characterized in that, In step S200, 2 ml of the initial suspension is added to the PE tube, and 60 mg of MAI is added. After adding the magnetic flux and MAI, the mixture is stirred and heated at 80-90°C and 1600 rpm for 6-10 hours.

5. The method for preparing a perovskite thin film by blade coating according to claim 4, characterized in that, In step S200, when the suspension is precipitated, 60 mg of PAN is added. After adding PAN, the mixture is stirred for 30 min until the viscosity of the suspension reaches 900-1000 mPa·s as measured by a rotational viscometer at 30 rpm.

6. A method for preparing a perovskite thin film by blade coating according to any one of claims 1-3, characterized in that, In step S300, the pixelated substrate has a size of 400mm×400mm and is cleaned using plasma or ultraviolet-ozone treatment. In step S300, 10 ml of the precursor suspension is poured onto the pixelated substrate and the coating speed is 0.6-0.8 m / s.

7. A method for preparing a perovskite thin film by blade coating according to any one of claims 1-3, characterized in that, In step S400, the volume of the mixed solvent of GBL and DMF added to the bubbler is 30-40 ml, and the mixing ratio of GBL and DMF in the mixed solution is 5:1-3:

1.

8. The method for preparing a perovskite thin film by blade coating according to claim 7, characterized in that, In step S400, the water bath heating temperature is 60-80℃, and the flow rate of high-purity nitrogen is controlled at 250-300 sccm. When nitrogen is introduced, the initial temperature of the heating stage is set to 80-85℃. The film is heated continuously for 2-3 hours. Then the gas supply is turned off, and the temperature of the heating stage is adjusted to 100℃. The film is heated continuously for 7-8 hours.

9. An apparatus for preparing perovskite thin films by a blade coating method, used to implement the blade coating method for preparing perovskite thin films as described in any one of claims 1-8, characterized in that, include: Pixelated base plate (1); The pixelated substrate (1) is covered with an ITO carrier transport layer (2). A perovskite layer (3) and a metal electrode layer (4) are formed on the surface of the ITO carrier transport layer (2). The metal electrode layer (4) is located on one side of the ITO carrier transport layer (2). The surface of the perovskite layer (3) is also provided with a metal electrode layer (4).

10. A perovskite thin film, characterized in that, It is prepared using a blade coating method as described in any one of claims 1-8 for perovskite thin films.

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