Passivation layer preparation system and method

Abstract

The invention provides a preparation system and method of a passivation layer. The system comprises a transmission mechanism which is provided with a transmission support assembly and is used for bearing and transmitting a substrate; an ultrasonic spraying device, a heating annealing device, a spraying cleaning device and an online monitoring unit are sequentially arranged above the conveying mechanism in the conveying direction of the conveying mechanism, and the ultrasonic spraying device is used for ultrasonically spraying a mixed solution containing a monomolecular layer material on the surface of a substrate to form the substrate paved with a liquid film; the heating and annealing device is used for heating and annealing the substrate on which the liquid film is laid, so that the monomolecular layer material is self-assembled to obtain a self-assembled layer; the spraying and cleaning device is used for spraying and cleaning the substrate provided with the self-assembly layer so as to remove a monomolecular layer material which is weakly combined with the substrate in the self-assembly layer, and a sample to be detected is obtained; the online monitoring unit is used for detecting the thickness of the self-assembly layer in the sample to be detected and the coverage rate of the self-assembly layer on the surface of the substrate, and the qualified sample is the substrate provided with the passivation layer.

Description

Technical Field

[0001] The present invention relates to the technical field of perovskite solar cell preparation, and in particular to a system and method for preparing a passivation layer. Background Art

[0002] Perovskite solar cells (PSCs) have become the most commercially viable new photovoltaic devices due to their low cost, high efficiency, solution processability and large-area preparation. Although the photoelectric conversion efficiency of perovskite solar cells has been greatly improved from the initial 3.8% to more than 26%, there is still a large gap with its theoretical efficiency (33%). Although the stability life of the device has been extended from the initial few minutes to thousands of hours, it is still far from the commercial standard or the service life of more than 25 years of crystalline silicon.

[0003] Studies have shown that during the low-temperature liquid phase preparation of perovskite solar cells, factors such as annealing temperature and crystallization rate can affect the surface and grain boundaries of the perovskite (PVK) film, and lead to the formation of various defects at different interface locations such as the hole transport layer (HTL) or electron transport layer (ETL) of the device. Self-assembled monolayer (SAM) molecules improve the photoelectric conversion efficiency by reducing the resistance of the transport layer, creating interface dipole moments, and reducing interface recombination with the perovskite absorption layer. The introduction of SAM can significantly improve the wet-heat stability and operational stability of perovskite solar cells, providing an effective strategy for the commercialization and long-term application of perovskite solar cells.

[0004] However, the current passivation methods for self-assembled monolayers mainly use wet spin coating or evaporation. In the laboratory, small perovskite solar cells can use a fast and simple spin coating method; when it comes to larger area cells, the thermal evaporation process is energy-intensive and difficult to control. The film layer required for the self-assembled monolayer is very thin, and high temperature will cause the bond between the anchoring group of the small self-assembled monolayer molecule and the substrate to break, making it difficult to form a suitable dense film layer.

[0005] Therefore, it is urgent to study and develop a perovskite passivation and monitoring method suitable for large-scale industrialization, which is of great significance for improving the photoelectric conversion efficiency and stability of perovskite solar cells. Summary of the invention

[0006] The main purpose of the present invention is to provide a system and method for preparing a passivation layer to solve the problem in the prior art that the passivation layer suitable for perovskite solar cells is difficult to achieve large-scale industrial production, and the photoelectric conversion efficiency and stability of perovskite solar cells need to be improved.

[0007] In order to achieve the above-mentioned purpose, the present invention provides a preparation system of a passivation layer on one hand, which preparation system comprises: a transmission mechanism, having a transmission support component, for carrying and transmitting a substrate; an ultrasonic spraying device, a heating annealing device, a spray cleaning device and an online monitoring unit are sequentially arranged above the transmission mechanism according to the transmission direction of the transmission mechanism; the ultrasonic spraying device is used to ultrasonically spray a mixed liquid containing a monomolecular layer material on the surface of the substrate to form a substrate covered with a liquid film; the heating annealing device is used to perform a heating annealing treatment on the substrate covered with the liquid film so that the monomolecular layer material self-assembles to obtain a self-assembled layer; the spray cleaning device is used to spray clean the substrate provided with the self-assembled layer to remove the monomolecular layer material weakly bound to the substrate in the self-assembled layer to obtain a sample to be tested; the online monitoring unit is used to detect the thickness of the self-assembled layer in the sample to be tested and the coverage rate of the self-assembled layer on the substrate surface, and a qualified sample is a substrate provided with a passivation layer.

[0008] Furthermore, the ultrasonic spraying device includes at least one spraying component, which is a disc-shaped structure provided with a through hole.

[0009] Furthermore, the heating annealing device is selected from a microwave heating device or a far infrared heating device.

[0010] Furthermore, the spray cleaning device includes a spray component, which is a disc-shaped structure provided with a through hole.

[0011] Furthermore, the online monitoring unit includes a soft X-ray reflectivity testing device and an online near-infrared testing device.

[0012] Furthermore, the thickness of the self-assembled layer is 2 to 12 nm, and the coverage is ≥ 98% for qualified samples.

[0013] Furthermore, the above-mentioned preparation system also includes a liquid recovery device for recovering waste liquid after spray cleaning.

[0014] Furthermore, the above-mentioned preparation system also includes a control center for controlling the working parameters of the transmission mechanism, the ultrasonic spraying device, the heating annealing device, the spray cleaning device and the online monitoring unit.

[0015] Furthermore, the above-mentioned preparation system also includes a substrate recovery device for screening and recovering unqualified samples according to the test results of the online monitoring unit.

[0016] Furthermore, the transmission support assembly transmits the substrate at a rate of 100 to 300 mm / s.

[0017] In order to achieve the above-mentioned purpose, another aspect of the present invention further provides a method for preparing a passivation layer, which is prepared by using the preparation system of the passivation layer provided by the present application. The preparation method comprises: fixing a substrate on a side surface of a transmission mechanism close to an ultrasonic spraying device to transmit the substrate; the transmission mechanism has a transmission support component; when the substrate is transmitted to the bottom of the ultrasonic spraying device, the ultrasonic spraying device ultrasonically sprays a mixed liquid containing a monomolecular layer material on the surface of the substrate to form a substrate covered with a liquid film; when the substrate is transmitted to the bottom of the heating annealing device, the heating annealing device performs heating annealing treatment on the substrate covered with the liquid film so that the monomolecular layer material self-assembles to obtain a self-assembled layer; when the substrate is transmitted to the bottom of the spray cleaning device, the spray cleaning device sprays and cleans the substrate provided with the self-assembled layer to remove the monomolecular layer material weakly bound to the substrate in the self-assembled layer to obtain a sample to be tested; when the substrate is transmitted to the bottom of the online monitoring unit, the online monitoring unit detects the thickness and passivation bonding state of the sample to be tested, and a qualified sample is a substrate provided with a passivation layer.

[0018] Furthermore, the substrate is selected from a laminated structure of a transparent conductive substrate and a hole transport layer, and preferably the transparent conductive substrate is selected from FTO conductive glass, ITO conductive glass or AZO conductive glass.

[0019] Further, the monolayer material is selected from carbazole derivatives and / or triarylamine compounds; preferably, the carbazole derivative is selected from one or more of the group consisting of [2-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl]phosphonic acid, [4-(3,6-dimethyl-9H-carbazole-9-yl)butyl]phosphonic acid and (4-(5,9-dibromo-7H-dibenzo[c,g]carbazole-7-yl)butyl)phosphonic acid; preferably, the triarylamine compound is selected from one or more of the group consisting of 4,4"-bis(diphenylamino)-1,1':3',1"-triphenyl-5'-carboxylic acid, 4'-[bis(2',4'-dimethoxybiphenyl-4-yl)amino]-biphenyl-4-carboxylic acid and (3-(7-(4-(bis(4-methoxyphenyl)amino)phenyl)benzo[1,2,5]thiadiazole-4-yl)-2-cyanoacrylic acid.

[0020] Furthermore, in the mixed solution, the mass concentration of the monomolecular layer material is 0.2 to 5 mg / mL.

[0021] Furthermore, the solvent in the mixed solution is selected from one or more of the group consisting of ethanol, propanol and DMF.

[0022] Furthermore, the ultrasonic spraying device includes a spraying component, the ultrasonic frequency of the ultrasonic spraying is 20-200 Hz, the pressure of the spraying component is 10-80 kPa, the vertical distance between the spraying component and the substrate is 5-10 cm, and the width of the ultrasonic spraying is 30-40 cm.

[0023] Further, the heating annealing device is selected from a microwave heating device, and preferably the power of the microwave heating device is 600-1500W; or, the heating annealing device is selected from a far-infrared heating device, and preferably the power of the far-infrared heating device is 1000-3000W, so that the temperature of the substrate covered with the liquid film is 100-120°C.

[0024] Furthermore, the spray cleaning device includes a spray component. During the spray cleaning process, the pressure of the spray component is 200-400 kPa, and the flow rate of the liquid for spray cleaning is 10-100 mL / min.

[0025] Furthermore, an organic solvent is used for spray cleaning, and preferably the organic solvent is selected from one or more of the group consisting of ethanol, propanol and DMF; more preferably, the organic solvent is the same as the solvent in the mixed solution.

[0026] When the technical solution of the present invention is applied, the conventional large-scale production of the passivation layer usually adopts a thermal evaporation process, which has high energy consumption and is difficult to accurately control the thickness of the passivation layer, especially when preparing an ultra-thin self-assembled monolayer. The preparation system provided by the present application uses an ultrasonic spraying device to ultrasonically spray a mixed liquid containing a monolayer material on the surface of a substrate, and then performs a heating annealing treatment on it, and uses a spray cleaning device to remove the monolayer material with weak binding force with the substrate in the self-assembled layer, so that the obtained sample to be tested contains only a self-assembled monolayer, which is a layer close to the surface of the substrate, and the chemical groups therein form a strong force with the surface of the substrate.

[0027] In short, the use of the above-mentioned preparation system of the present application can not only realize automated production, reduce energy consumption, and obtain an ultra-thin passivation layer (thickness of 2 to 12 nm), but also can perform online monitoring of the prepared samples to be tested, screen out qualified samples, and improve product yield. The above-mentioned substrate provided with a passivation layer is used to prepare a perovskite solar cell, which can improve the crystallinity and film quality of the perovskite active layer prepared on its surface, thereby improving the photoelectric conversion efficiency and stability of the perovskite solar cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0029] Figure 1 A schematic structural diagram of a system for preparing a passivation layer provided in the present application is shown;

[0030] Figure 2 A schematic diagram of the stacked structure of the perovskite solar cell prepared in the examples and comparative examples of the present application is shown;

[0031] Figure 3 The JV curves of the perovskite solar cells prepared in Example 1 and Comparative Example 1 of the present application are shown.

[0032] The above drawings include the following reference numerals:

[0033] 100, ultrasonic spraying device; 200, heating annealing device; 300, spray cleaning device; 400, online monitoring unit; 500, liquid recovery device; 600, control center; 700, substrate recovery device;

[0034] 10. Passivation layer; 20. ITO transparent conductive glass; 30. Hole transport layer; 40. Perovskite active layer; 50. Electron transport layer; 60. Metal conductive layer. DETAILED DESCRIPTION

[0035] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present invention will be described in detail below in conjunction with the embodiments.

[0036] As described in the background technology, the existing passivation layer suitable for perovskite solar cells is difficult to achieve large-scale industrial production, and the photoelectric conversion efficiency and stability of perovskite solar cells need to be improved. In order to solve the above technical problems, the present application provides a passivation layer preparation system, such as Figure 1 As shown, the preparation system includes: a transmission mechanism, which has a transmission support component for carrying and transmitting a substrate a; according to the transmission direction of the transmission mechanism, an ultrasonic spraying device 100, a heating annealing device 200, a spray cleaning device 300 and an online monitoring unit 400 are sequentially arranged above the transmission mechanism, wherein the ultrasonic spraying device 100 is used to ultrasonically spray a mixed liquid containing a monolayer material on the surface of the substrate a to form a substrate a covered with a liquid film; the heating annealing device 200 is used to perform heating annealing treatment on the substrate a covered with the liquid film so that the monolayer material is self-assembled to obtain a self-assembled layer; the spray cleaning device 300 is used to spray clean the substrate a provided with the self-assembled layer to remove the monolayer material weakly bound to the substrate a in the self-assembled layer to obtain a sample to be tested; the online monitoring unit 400 is used to detect the thickness of the self-assembled layer in the sample to be tested and the coverage of the self-assembled layer on the surface of the substrate a, and the qualified sample is the substrate a provided with a passivation layer.

[0037] The conventional large-scale production of the passivation layer usually adopts a thermal evaporation process, which has high energy consumption and is difficult to accurately control the thickness of the passivation layer, especially when preparing an ultra-thin self-assembled monolayer. The preparation system provided by the present application uses an ultrasonic spraying device 100 to ultrasonically spray a mixed liquid containing a monolayer material on the surface of a substrate a, and then performs a heating annealing treatment on it, and uses a spray cleaning device 300 to remove the monolayer material with a weak binding force with the substrate a in the self-assembled layer, so that the obtained sample to be tested contains only a self-assembled monolayer, which is a layer close to the surface of the substrate a, and the chemical groups therein form a strong force with the surface of the substrate a.

[0038] In short, the use of the above-mentioned preparation system of the present application can not only realize automated production, reduce energy consumption, and obtain an ultra-thin passivation layer (thickness of 2 to 12 nm), but also can perform online monitoring of the prepared samples to be tested, screen out qualified samples, and improve product yield. The above-mentioned substrate provided with a passivation layer is used to prepare a perovskite solar cell, which can improve the crystallinity and film quality of the perovskite active layer prepared on its surface, thereby improving the photoelectric conversion efficiency and stability of the perovskite solar cell.

[0039] It should be noted that in the present application, the monomolecular layer material weakly bonded to substrate a in the self-assembled layer refers to the monomolecular layer material in the second to nth layers (n>2) except the self-assembled monolayer close to the surface of substrate a.

[0040] In a preferred embodiment, the ultrasonic spraying device 100 includes at least one spraying component, which is a disc-shaped structure provided with a through hole. The arrangement of the spraying component enables the mixed liquid containing the monomolecular layer material to be sprayed out from the through hole to form a spray and deposited on the surface of the substrate a, thereby realizing the preparation of the liquid film and facilitating the subsequent preparation of the self-assembled layer. Arranging multiple spraying components is conducive to improving production efficiency.

[0041] The microwave heating device can use microwaves to generate heat for the material to be heated, has high thermal efficiency, and the material to be heated is heated evenly, and is easy to realize automatic control. The far-infrared heating device can emit infrared light so that the material to be heated absorbs part of the infrared light. When the wavelength of the infrared light emitted by the far-infrared heating device is the same as the absorption wavelength of the material to be heated, the molecules inside the material to be heated resonate to generate heat and are heated. In a preferred embodiment, the heating annealing device 200 includes but is not limited to a microwave heating device or a far-infrared heating device. Compared with other heating annealing devices 200, the use of the above types is conducive to uniform heating of the substrate a covered with a liquid film, which is convenient for self-assembly of single-molecule materials and is convenient for precise temperature control.

[0042] In a preferred embodiment, the spray cleaning device 300 includes a spray component, which is a disc-shaped structure provided with through holes. The spray component can spray clean the substrate a provided with the self-assembled layer, thereby facilitating the removal of the monomolecular layer material with weak binding force with the substrate a in the self-assembled layer, so that the obtained sample to be tested contains only the self-assembled monolayer.

[0043] In a preferred embodiment, the preparation system further comprises a liquid recovery device 500 for recovering waste liquid after spray cleaning. The provision of the liquid recovery device 500 is conducive to reducing waste, thereby reducing costs and facilitating green recycling of waste liquid.

[0044] In order to monitor the thickness of the self-assembled layer and the coverage of the self-assembled layer on the surface of the substrate a in real time, thereby improving the controllability and consistency of the passivation layer, in a preferred embodiment, the online monitoring unit 400 includes a soft X-ray reflectivity test device and an online near-infrared test device. Preferably, the thickness of the self-assembled layer is 2 to 12 nm, and the coverage is ≥98% for a qualified sample.

[0045] In a preferred embodiment, the preparation system further includes a control center 600 for controlling the working parameters of the transmission mechanism, the ultrasonic spraying device 100, the heating annealing device 200, the spray cleaning device 300 and the online monitoring unit 400. The setting of the control center 600 is conducive to large-scale industrial production, and is convenient for improving production efficiency and realizing automation.

[0046] In order to improve the yield rate of the passivation layer, the prepared products are screened. Preferably, the above-mentioned preparation system also includes a substrate a recovery device 700, which is used to screen and recover unqualified samples according to the test results of the online monitoring unit 400.

[0047] In a preferred embodiment, the transmission support assembly transmits the substrate a at a rate of 100 to 300 mm / s. The transmission rate includes but is not limited to the above range, and limiting it within the above range is conducive to improving the production efficiency of the passivation layer, and is also conducive to making the obtained passivation layer more uniform, and is conducive to reducing the interface defects between the passivation layer and the substrate a, thereby improving product quality.

[0048] The present application also provides a method for preparing a passivation layer, which is carried out using the above-mentioned passivation layer preparation system provided by the present application. The preparation method comprises: fixing a substrate a on a side surface of a transmission mechanism close to an ultrasonic spraying device 100, and transmitting the substrate a; the transmission mechanism has a transmission support component; when the substrate a is transmitted to the bottom of the ultrasonic spraying device 100, the ultrasonic spraying device 100 ultrasonically sprays a mixed liquid containing a monomolecular layer material on the surface of the substrate a to form a substrate a covered with a liquid film; when the substrate a is transmitted to the bottom of the heating annealing device 200, the heating The thermal annealing device 200 performs heating annealing treatment on the substrate a covered with the liquid film so as to allow the monomolecular layer material to self-assemble and obtain a self-assembled layer; when being transmitted to the bottom of the spray cleaning device 300, the spray cleaning device 300 sprays and cleans the substrate a provided with the self-assembled layer to remove the monomolecular layer material weakly bound to the substrate a in the self-assembled layer to obtain a sample to be tested; when being transmitted to the bottom of the online monitoring unit 400, the online monitoring unit 400 detects the thickness and passivation bonding state of the sample to be tested, and a qualified sample is the substrate a provided with a passivation layer.

[0049] The conventional large-scale production of the passivation layer usually adopts a thermal evaporation process, which has high energy consumption and is difficult to accurately control the thickness of the passivation layer, especially when preparing an ultra-thin self-assembled monolayer. The above-mentioned preparation method provided by the present application uses an ultrasonic spraying device 100 to ultrasonically spray a mixed liquid containing a monolayer material on the surface of a substrate a, and then performs a heating annealing treatment on it, and uses a spray cleaning device 300 to remove the monolayer material with a weak binding force with the substrate a in the self-assembled layer, so that the obtained sample to be tested contains only a self-assembled monolayer, which is a layer close to the surface of the substrate a, and the chemical groups therein form a strong force (hydrogen bond or coordination bond) with the surface of the substrate a.

[0050] In short, the use of the above-mentioned preparation system of the present application can not only realize automated production, reduce energy consumption, and obtain an ultra-thin passivation layer (thickness of 2 to 12 nm), but also can perform online monitoring of the prepared samples to be tested, screen out qualified samples, and improve product yield. The above-mentioned substrate provided with a passivation layer is used to prepare a perovskite solar cell, which can improve the crystallinity and film quality of the perovskite active layer prepared on its surface, thereby improving the photoelectric conversion efficiency and stability of the perovskite solar cell.

[0051] The present application can prepare a passivation layer for various types of substrates a, and its application in the preparation process of perovskite solar cells is conducive to improving its photoelectric conversion efficiency and stability. In a preferred embodiment, substrate a includes but is not limited to a laminated structure of a transparent conductive substrate and a hole transport layer. Preferably, the transparent conductive substrate includes but is not limited to FTO conductive glass, ITO conductive glass or AZO conductive glass; the material of the hole transport layer includes but is not limited to one or more of the group consisting of NiOx (nickel oxide), PTTA and Spiro-OMeTAD. In addition, the present application has no particular restrictions on the thickness of substrate a.

[0052] Compared with other passivation materials, monolayer materials (SAM) have highly adaptable structural modifications and special processing properties, which are beneficial to improving the photoelectric conversion efficiency of perovskite solar cells. In a preferred embodiment, the monolayer materials include but are not limited to carbazole derivatives and / or triarylamine compounds.

[0053] In order to improve the formation of hydrogen bonds between the monomolecular material and the substrate surface or the formation of coordination bonds when the substrate contains metal elements, further exert the passivation effect of the passivation layer, and further improve the crystallinity and film quality of the subsequently prepared perovskite film, preferably, the carbazole derivatives include but are not limited to [2-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl]phosphonic acid (MeO-2PACz), [4-(3,6-dimethyl-9H-carbazole-9-yl)butyl]phosphonic acid (Me-4PACz) and (4-(5,9-dibromo-7H-dibenzo[ c,g]carbazole-7-yl)butyl)phosphonic acid (DCB-BPA) one or more; triarylamine compounds include but are not limited to one or more selected from the group consisting of 4,4"-bis(diphenylamino)-1,1':3',1"-triphenyl-5'-carboxylic acid, 4'-[bis(2',4'-dimethoxybiphenyl-4-yl)amino]-biphenyl-4-carboxylic acid and (3-(7-(4-(bis(4-methoxyphenyl)amino)phenyl)benzo[1,2,5]thiadiazol-4-yl)-2-cyanoacrylic acid.

[0054] In a preferred embodiment, the mass concentration of the monolayer material in the mixed solution is 0.2-5 mg / mL. The mass concentration of the monolayer material includes but is not limited to the above range, and limiting it within the above range is conducive to ultrasonic spraying and subsequent formation of a self-assembled layer of appropriate thickness, thereby reducing waste of the monolayer material.

[0055] In order to improve the dispersibility of the monolayer material and the uniformity of the mixed solution, preferably, the solvent in the mixed solution includes but is not limited to one or more of the group consisting of ethanol, propanol and DMF.

[0056] In a preferred embodiment, the ultrasonic spraying device 100 includes a spraying component, the ultrasonic frequency of the ultrasonic spraying is 20 to 200 Hz, and the pressure of the spraying component is 10 to 80 kPa. The ultrasonic frequency of the ultrasonic spraying and the pressure of the spraying component include but are not limited to the above ranges, and limiting them within the above ranges is conducive to improving the uniformity of the liquid film, thereby facilitating the subsequent formation of a self-assembled layer with uniform quality and fewer defects.

[0057] In a preferred embodiment, the vertical distance between the spraying component and the substrate a is 5 to 10 cm, the width of the ultrasonic spraying is 30 to 40 cm, and the liquid flow rate of the spray cleaning is 10 to 100 mL / min. The vertical distance between the spraying component and the substrate a and the width of the ultrasonic spraying include but are not limited to the above ranges. Limiting them within the above ranges is conducive to improving production efficiency while more accurately controlling the thickness of the liquid film, which is conducive to the subsequent formation of a self-assembled layer with uniform quality and fewer defects.

[0058] It should be noted that the width of ultrasonic spraying in the present application refers to the width of the spray generated by spraying within the vertical distance between the above-mentioned spraying component and the substrate a on the receiving surface (the plane where the surface of the substrate a is located).

[0059] In a preferred embodiment, the heating annealing device 200 includes but is not limited to a microwave heating device, preferably the power of the microwave heating device is 600-1500W; or, the heating annealing device 200 includes but is not limited to a far-infrared heating device, preferably the power of the far-infrared heating device is 1000-3000W, so that the temperature of the substrate a with the liquid film is 100-120° C. Compared with other heating annealing process conditions, the above process conditions are conducive to making the substrate a with the liquid film more uniformly heated, facilitating the self-assembly of the monomolecular material, and facilitating more precise temperature control.

[0060] In a preferred embodiment, the spray cleaning device 300 includes a spray component, and the pressure of the spray component during the spray cleaning process is 200-400 kPa. The pressure of the spray component includes but is not limited to the above range, and limiting it within the above range is conducive to improving the removal rate of the monolayer material with weak bonding force with the substrate a in the self-assembled layer, so that the obtained sample to be tested contains only the self-assembled monolayer, and the thickness of the self-assembled monolayer is more uniform, and the surface defects are less.

[0061] In order to further improve the removal rate of the monolayer material with weaker bonding force with substrate a in the self-assembled layer, so that the thickness of the self-assembled monolayer in the sample to be tested is more uniform and the surface defects are less, preferably, an organic solvent is used for spray cleaning, and the preferred organic solvent includes but is not limited to one or more of the group consisting of ethanol, propanol and DMF.

[0062] In order to further improve the removal rate of the monolayer material with weaker bonding force with substrate a in the self-assembled layer, so as to make the thickness of the self-assembled monolayer in the sample to be tested more uniform and have fewer surface defects, preferably, the organic solvent is the same as the solvent in the mixed solution.

[0063] The present application is further described in detail below in conjunction with specific embodiments. These embodiments should not be construed as limiting the scope of protection claimed in the present application.

[0064] Example 1

[0065] A method for preparing a passivation layer 10, using Figure 1 The preparation system of the passivation layer 10 shown is prepared, including:

[0066] A hole transport layer 30 with a thickness of 20 nm is prepared on the conductive surface side of the ITO transparent conductive glass 20 as a substrate a of this embodiment; wherein the hole transport material is NiOx;

[0067] A substrate a with a size of 30 cm×30 cm is fixed on a side surface of a transmission support assembly close to an ultrasonic spray device 100 (including three spraying parts), and a transmission mechanism is set to transmit the substrate a at a rate of 200 mm / s; when the substrate a is transmitted to the bottom of the ultrasonic spray device 100, the ultrasonic spray device 100 is started, and an ethanol mixed solution containing MeO-2PACz is sprayed on the surface of the substrate a to form a substrate a covered with a liquid film, wherein the mass concentration of MeO-2PACz in the mixed solution is 1.2 mg / mL, the ultrasonic frequency of the ultrasonic spraying is Hz, the spraying pressure is 60 kPa, the vertical distance between the spraying part and the substrate a is 8 cm, and the width of the ultrasonic spraying is 35 cm;

[0068] Subsequently, the substrate a continues to move along the transmission path to the bottom of the microwave heating device, the heating annealing device 200 is started, and the substrate a provided with the liquid film is subjected to heating annealing treatment, so that the MeO-2PACz is self-assembled on the substrate a to form a self-assembled layer; wherein the power of the heating annealing device 200 (microwave heating device) is set to 1200W, so that the temperature of the substrate a provided with the liquid film is 110°C; the substrate a continues to be transmitted to the bottom of the spray cleaning device 300, the spray cleaning device 300 is started, and ethanol is used to spray clean the substrate a provided with the self-assembled layer at a rate of 25mL / min, and the pressure of the spray component is 240kPa, so as to remove the MeO-2PACz part in the self-assembled layer with weaker bonding force with the substrate a, and obtain the sample to be tested;

[0069] Finally, the substrate a is transferred to the bottom of the online monitoring unit 400, and the soft X-ray reflectivity test device and the online near-infrared test device are started. The soft X-ray reflectivity test device measures the thickness of the self-assembled layer in the sample to be tested, and the online near-infrared test device measures the coverage of the self-assembled layer on the surface of the substrate a. Samples with a thickness in the range of 2 to 8 nm and a coverage of ≥98% are qualified samples.

[0070] The above-mentioned preparation system also includes a control center 600, which is used to control the working parameters of the transmission mechanism, the ultrasonic spraying device 100, the heating annealing device 200, the spray cleaning device 300 and the online monitoring unit 400; in addition, the preparation system is also equipped with a substrate a recovery device 700 and a liquid recovery device 500, which are used to screen and recover unqualified samples according to the test results of the online monitoring unit 400, and to recover the waste liquid after spray cleaning.

[0071] Example 2

[0072] The difference from Example 1 is that the speed at which the transmission support assembly transmits substrate a is set to 100 mm / s.

[0073] Example 3

[0074] The difference from Example 1 is that the speed at which the transmission support assembly transmits substrate a is set to 300 mm / s.

[0075] Example 4

[0076] The difference from Example 1 is that the speed at which the transmission support assembly transmits substrate a is set to 400 mm / s.

[0077] Example 5

[0078] The difference from Example 1 is that the monomolecular layer material is Me-4PACz.

[0079] Example 6

[0080] The difference from Example 1 is that the monomolecular layer material is DCB-BPA.

[0081] Example 7

[0082] The difference from Example 1 is that the mass concentration of the monomolecular layer material is 0.2 mg / mL.

[0083] Example 8

[0084] The difference from Example 1 is that the mass concentration of the monomolecular layer material is 5 mg / mL.

[0085] Example 9

[0086] The difference from Example 1 is that the mass concentration of the monomolecular layer material is 20 mg / mL.

[0087] Example 10

[0088] The difference from Example 1 is that the ultrasonic frequency of ultrasonic spraying is 20 Hz, the pressure of the sprayed part is 80 kPa, and the vertical distance between the sprayed part and substrate a is 5 cm.

[0089] Embodiment 11

[0090] The difference from Example 1 is that the ultrasonic frequency of ultrasonic spraying is 200 Hz, the pressure of the sprayed part is 10 kPa, and the vertical distance between the sprayed part and substrate a is 10 cm.

[0091] Example 12

[0092] The difference from Example 1 is that the ultrasonic frequency of ultrasonic spraying is 200 Hz, the pressure of the sprayed part is 10 kPa, and the vertical distance between the sprayed part and substrate a is 20 cm.

[0093] Embodiment 13

[0094] The difference from Example 1 is that the power of the microwave heating device is changed to 600 W, and the temperature of the substrate a covered with the liquid film is set to 100°C.

[0095] Embodiment 14

[0096] The difference from Example 1 is that the power of the microwave heating device is changed to 1500W, so that the temperature of the substrate a covered with the liquid film is 120°C.

[0097] Embodiment 15

[0098] The difference from Example 1 is that the power of the microwave heating device is changed to 600 W, so that the temperature of the substrate a with the liquid film is 70°C.

[0099] Example 16

[0100] The difference from Example 1 is that the pressure of the spray component is 200 kPa, and the flow rate of the spray cleaning liquid is 10 mL / min.

[0101] Embodiment 17

[0102] The difference from Example 1 is that the pressure of the spray component is 400 kPa, and the flow rate of the spray cleaning liquid is 100 mL / min.

[0103] Embodiment 18

[0104] The difference from Example 1 is that the pressure of the spray component is 450 kPa, and the flow rate of the liquid for spray cleaning is 300 mL / min.

[0105] Comparative Example 1

[0106] The difference from Example 1 is that an intermittent method is used to sequentially perform ultrasonic spraying, microwave heating and spray cleaning on substrate a to obtain a sample to be tested, wherein the processing time of ultrasonic spraying is 4s, the processing time of microwave heating is 300s, and the processing time of spray cleaning is 3s. The sample to be tested is transferred to a soft X-ray reflectivity testing device to test the thickness of the self-assembled layer in the sample to be tested, and samples with a thickness in the range of 2 to 8nm are screened. These samples are transferred to an online near-infrared testing device to test the coverage of the self-assembled layer on the surface of substrate a, and samples with a coverage ≥98% are screened as qualified samples.

[0107] Comparative Example 2

[0108] The difference from Example 1 is that the preparation system does not include the spray cleaning device 300. The thickness of the self-assembled layer in the prepared sample to be tested is 30 nm.

[0109] Comparative Example 3

[0110] The difference from Example 1 is that the preparation system does not include an online monitoring unit 400, which results in reduced production efficiency and requires manual transfer to a soft X-ray reflectivity testing device to test the thickness of the self-assembled layer in the sample to be tested, and transfer to an online near-infrared testing device to test the coverage of the self-assembled layer on the surface of substrate a.

[0111] The substrate a provided with the passivation layer 10 prepared in all the above-mentioned embodiments and comparative examples was prepared into a perovskite solar cell and the photovoltaic performance test was carried out.

[0112] The preparation method of perovskite solar cells is as follows:

[0113] (1) Perovskite active layer 40:

[0114] In a nitrogen-filled glove box, PbI 2 , PbBr, CsI, FAI and MAI powders were dispersed in 20 mL of DMF at a molar ratio of 2:0.2:0.1:1:0.6, and stirred for 5 h until completely dissolved to obtain a perovskite precursor solution; the perovskite precursor solution was coated on the surface of one side of the substrate a provided in the present application close to the passivation layer 10 by a slit coating method, and heat treated at 120° C. for 30 min to obtain a (CsPbI 3 ) 0.05 (FAPbI 3 ) 0.9 (MAPbBr 3 ) 0.05 layer;

[0115] (2) Preparation of electron transport layer 50:

[0116] In (CsPbI 3 ) 0.05 (FAPbI 3 ) 0.9 (MAPbBr 3 ) 0.05 A layer of C with a thickness of 20 nm is deposited on the surface of the layer away from the perovskite active layer 40 by atomic layer deposition. 60 ;

[0117] (3) Preparation of metal conductive layer 60:

[0118] A 150 nm thick Ag layer is deposited on the surface of the electron transport layer 50 away from the perovskite active layer 40 to obtain a perovskite solar cell.

[0119] The perovskite solar cell has Figure 2 The stacked structure shown is represented by:

[0120] ITO / NiO x / Me-4PACz / (CsPbI 3 ) 0.05 (FAPbI 3 ) 0.9 (MAPbBr 3 ) 0.05 / C 60 / Ag.

[0121] The photovoltaic performance of the perovskite solar cell devices prepared in all the above embodiments and comparative examples of the present application was tested. The effective area of ​​the devices was 560 cm 2 ; Test conditions are as follows: spectral distribution AM1.5G, light intensity 100mW / cm 2 The JV curves were measured by forward and reverse scanning. The results are shown in Table 1. Figure 3 .

[0122] Table 1

[0123]

[0124] From the above description, it can be seen that the above embodiments of the present invention achieve the following technical effects:

[0125] The conventional large-scale production of the passivation layer usually adopts a thermal evaporation process, which has high energy consumption and is difficult to accurately control the thickness of the passivation layer, especially when preparing an ultra-thin self-assembled monolayer. The preparation system provided by the present application uses an ultrasonic spraying device 100 to ultrasonically spray a mixed liquid containing a monolayer material on the surface of a substrate a, and then performs a heating annealing treatment on it, and uses a spray cleaning device 300 to remove the monolayer material with a weak binding force with the substrate a in the self-assembled layer, so that the obtained sample to be tested contains only a self-assembled monolayer, which is a layer close to the surface of the substrate a, and the chemical groups therein form a strong force with the surface of the substrate a.

[0126] In short, the use of the above-mentioned preparation system of the present application can not only realize automated production, reduce energy consumption, and obtain an ultra-thin passivation layer (thickness of 2 to 12 nm), but also can perform online monitoring of the prepared samples to be tested, screen out qualified samples, and improve product yield. The above-mentioned substrate provided with a passivation layer is used to prepare a perovskite solar cell, which can improve the crystallinity and film quality of the perovskite active layer prepared on its surface, thereby improving the photoelectric conversion efficiency and stability of the perovskite solar cell.

[0127] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A system for preparing a passivation layer, characterized in that: The preparation system comprises: A transmission mechanism, having a transmission support assembly, for carrying and transmitting the substrate; According to the transmission direction of the transmission mechanism, an ultrasonic spraying device (100), a heating annealing device (200), a spray cleaning device (300) and an online monitoring unit (400) are sequentially arranged above the transmission mechanism; The ultrasonic spraying device (100) is used to ultrasonically spray a mixed liquid containing a monomolecular layer material onto the surface of the substrate to form a substrate covered with a liquid film; The heating and annealing device (200) is used to perform heating and annealing treatment on the substrate on which the liquid film is laid, so as to allow the monomolecular layer material to self-assemble to obtain a self-assembled layer; The spray cleaning device (300) is used to spray clean the substrate provided with the self-assembled layer, so as to remove the monomolecular layer material in the self-assembled layer that is weakly bound to the substrate, and obtain a sample to be tested; The online monitoring unit (400) is used to detect the thickness of the self-assembled layer in the sample to be tested and the coverage of the self-assembled layer on the surface of the substrate. The qualified sample is the substrate provided with the passivation layer.

2. The system for preparing a passivation layer according to claim 1, characterized in that: The ultrasonic spraying device (100) comprises at least one spraying component, which is a disc-shaped structure provided with a through hole; Preferably, the heating annealing device (200) is selected from a microwave heating device or a far infrared heating device; Preferably, the spray cleaning device (300) comprises a spray component, which is a disc-shaped structure provided with through holes.

3. The system for preparing a passivation layer according to claim 1 or 2, characterized in that: The online monitoring unit (400) comprises a soft X-ray reflectivity testing device and an online near-infrared testing device; Preferably, the thickness of the self-assembled layer is 2-12 nm, and the coverage is ≥98% for qualified samples.

4. The system for preparing a passivation layer according to any one of claims 1 to 3, characterized in that: The preparation system also includes a liquid recovery device (500) for recovering the waste liquid after the spray cleaning.

5. The system for preparing a passivation layer according to claim 1, characterized in that: The preparation system further comprises a control center (600) for controlling the working parameters of the transmission mechanism, the ultrasonic spraying device (100), the heating annealing device (200), the spray cleaning device (300) and the online monitoring unit (400); Preferably, the preparation system further comprises a substrate recovery device (700) for screening and recovering unqualified samples according to the test results of the online monitoring unit (400).

6. The system for preparing a passivation layer according to claim 1, characterized in that: The transmission support assembly transmits the substrate at a rate of 100 to 300 mm / s.

7. A method for preparing a passivation layer, characterized in that: The preparation method is carried out using the preparation system of the passivation layer according to any one of claims 1 to 6, and the preparation method comprises: The substrate is fixed on a side surface of a transmission mechanism close to the ultrasonic spraying device (100) to transport the substrate; the transmission mechanism has a transmission support component; When the substrate is conveyed to the bottom of the ultrasonic spray coating device (100), the ultrasonic spray coating device (100) ultrasonically sprays a mixed liquid containing a monomolecular layer material onto the surface of the substrate to form a substrate covered with a liquid film; when the substrate is conveyed to the bottom of the heating and annealing device (200), the heating and annealing device (200) performs a heating and annealing treatment on the substrate covered with the liquid film to allow the monomolecular layer material to self-assemble to obtain a self-assembled layer; when the substrate is conveyed to the bottom of the spray cleaning device (300), the spray cleaning device (300) sprays and cleans the substrate provided with the self-assembled layer to remove the monomolecular layer material in the self-assembled layer that is weakly bonded to the substrate to obtain a sample to be tested; when the substrate is conveyed to the bottom of the online monitoring unit (400), the online monitoring unit (400) detects the thickness and passivation bonding state of the sample to be tested, and a qualified sample is a substrate provided with the passivation layer.

8. The method for preparing a passivation layer according to claim 7, characterized in that: The substrate is selected from a laminated structure of a transparent conductive substrate and a hole transport layer, and preferably the transparent conductive substrate is selected from FTO conductive glass, ITO conductive glass or AZO conductive glass; Preferably, the monolayer material is selected from carbazole derivatives and / or triarylamine compounds; preferably, the carbazole derivative is selected from one or more of the group consisting of [2-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl]phosphonic acid, [4-(3,6-dimethyl-9H-carbazole-9-yl)butyl]phosphonic acid and (4-(5,9-dibromo-7H-dibenzo[c,g]carbazole-7-yl)butyl)phosphonic acid; preferably, the triarylamine compound is selected from one or more of the group consisting of 4,4″-bis(diphenylamino)-1,1′:3′,1″-triphenyl-5′-carboxylic acid, 4′-[bis(2′,4′-dimethoxybiphenyl-4-yl)amino]-biphenyl-4-carboxylic acid and (3-(7-(4-(bis(4-methoxyphenyl)amino)phenyl)benzo[1,2,5]thiadiazole-4-yl)-2-cyanoacrylic acid; Preferably, in the mixed solution, the mass concentration of the monolayer material is 0.2 to 5 mg / mL; Preferably, the solvent in the mixed solution is selected from one or more of the group consisting of ethanol, propanol and DMF.

9. The method for preparing a passivation layer according to claim 7, characterized in that: The ultrasonic spraying device (100) comprises a spraying component, the ultrasonic frequency of the ultrasonic spraying is 20 to 200 Hz, the pressure of the spraying component is 10 to 80 kPa, the vertical distance between the spraying component and the substrate is 5 to 10 cm, and the width of the ultrasonic spraying is 30 to 40 cm; Preferably, the heating annealing device (200) is selected from a microwave heating device, and preferably the power of the microwave heating device is 600 to 1500 W; or, the heating annealing device (200) is selected from a far-infrared heating device, and preferably the power of the far-infrared heating device is 1000 to 3000 W, so that the temperature of the substrate on which the liquid film is laid is 100 to 120°C.

10. The method for preparing a passivation layer according to claim 7, characterized in that: The spray cleaning device (300) comprises a spray component, the pressure of the spray component during the spray cleaning process is 200-400 kPa, and the flow rate of the liquid for the spray cleaning is 10-100 mL / min; Preferably, an organic solvent is used for the spray cleaning, and preferably the organic solvent is selected from one or more of the group consisting of ethanol, propanol and DMF; more preferably, the organic solvent is the same as the solvent in the mixed solution.

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