Perovskite quantum dot microarray packaging method, perovskite quantum dot microarray repairing method and perovskite quantum dot microarray preparation method

Abstract

The invention relates to the technical field of photoelectric materials and devices, in particular to a perovskite quantum dot microarray packaging method, a perovskite quantum dot microarray repairing method and a perovskite quantum dot microarray preparation method. The perovskite quantum dot microarray packaging method comprises the following steps: providing a perovskite quantum dot microarray, and providing packaging ink comprising 80-120 parts of matrix resin, 5-20 parts of a dynamic covalent cross-linking agent, 3-15 parts of a two-dimensional nano barrier filler, 0.5 part of a catalyst and a solvent; the dynamic covalent cross-linking agent is prepared from a polyurethane oligomer and bismaleimide; printing and packaging ink on the perovskite quantum dot microarray and the peripheral side of the perovskite quantum dot microarray; carrying out heat treatment at 80 DEG C for 5-10 minutes, and carrying out heat treatment at 120 DEG C for 1-3 minutes; and curing for 30-60 seconds under ultraviolet light of 365 nm until a packaging film is formed. The problems that the perovskite quantum dot microarray device is poor in environmental stability, the packaging layer is prone to brittle fracture and failure, and microscopic damage is irreversible are solved, and the service life and the stability of the perovskite quantum dot microarray device can be guaranteed.

Description

Perovskite quantum dot microarray encapsulation method, repair method, and fabrication method Technical Field

[0001] This application relates to the field of optoelectronic materials and devices, specifically to perovskite quantum dot microarray encapsulation methods, repair methods, and preparation methods. Background Technology

[0002] Perovskite quantum dot microarray devices, with their advantages such as high color purity and tunable emission wavelength, hold significant promise for next-generation display technologies. However, perovskite materials are highly sensitive to water, oxygen, and even light, and their environmental stability issues severely limit their practical application.

[0003] In the encapsulation stage of perovskite quantum dot microarray devices, traditional rigid encapsulation layers such as oxide films are prone to microcracks due to their high material brittleness. These microcracks easily form when the device is subjected to mechanical stress or repeated bending. Once formed, these microcracks provide direct pathways for water vapor and oxygen from the environment, leading to rapid phase separation or oxidative degradation of the perovskite quantum dot material and significant deterioration of the device's photoelectric performance. While flexible polymer encapsulation layers can alleviate stress problems, their large free volume between molecular chains results in insufficient long-term barrier capabilities against water and oxygen, failing to meet high reliability requirements.

[0004] For high-precision perovskite quantum dot microarray devices, each micrometer-scale pixel depends on the integrity of the encapsulation layer. Localized encapsulation failure not only leads to the loss of function of a single pixel but can also affect surrounding areas through thermal diffusion or electric field coupling, causing damage to display uniformity. Furthermore, existing encapsulation technologies lack the ability to repair microscopic damage; once microcracks or interface defects appear, the device's performance and lifespan are significantly affected. Therefore, perovskite quantum dot microarray devices suffer from insufficient environmental stability, susceptibility to encapsulation layer cracking and failure, and irreversible damage in practical applications. Summary of the Invention

[0005] In view of this, this application provides a perovskite quantum dot microarray encapsulation method, a repair method, and a fabrication method, which can effectively improve the environmental stability of perovskite quantum dot microarray devices and have potential damage repair capabilities.

[0006] To improve the above-mentioned technical problems, one technical solution adopted in this application is: providing a perovskite quantum dot microarray encapsulation method, comprising: providing a perovskite quantum dot microarray and providing encapsulation ink; the encapsulation ink, by weight, is uniformly prepared by mixing 80-120 parts of matrix resin, 5-20 parts of dynamic covalent crosslinking agent, 3-15 parts of two-dimensional nano barrier filler, 0.5 parts of catalyst, and solvent, wherein the dynamic covalent crosslinking agent includes furan-terminated polyurethane oligomers and bismaleimide; and utilizing high-precision inkjet printing... The system prints the encapsulation ink onto the perovskite quantum dot microarray and its periphery; heat-treats at 80°C for 5-10 minutes, followed by heat-treating at 120°C for 1-3 minutes; and cures under 365nm ultraviolet light for 30-60 seconds until an encapsulation film is formed on the perovskite quantum dot microarray and its periphery; wherein the matrix resin is a polydimethylsiloxane prepolymer and the solvent is n-heptane; or, the matrix resin is an aqueous polyurethane dispersion and the solvent is a mixed solution of deionized water and ethanol.

[0007] In one specific embodiment, during the gas chromatography-mass spectrometry detection, before the encapsulation ink is printed onto the perovskite quantum dot microarray and its periphery using a high-precision inkjet printing system, the provision of the perovskite quantum dot microarray includes: coating the perovskite quantum dot microarray and its periphery with a long-chain hydrophobic ligand or an inorganic passivation layer.

[0008] In one specific embodiment, the catalyst includes either boron trifluoride diethyl ether complex or trifluoromethanesulfonate.

[0009] In one specific embodiment, the matrix resin is a polydimethylsiloxane prepolymer, the solvent is n-heptane, and the catalyst includes a platinum catalyst.

[0010] In one specific embodiment, the encapsulation ink is prepared by mixing 100 parts of matrix resin, 20 parts of dynamic covalent crosslinking agent, 5 parts of two-dimensional nano barrier filler, and 0.5 parts of catalyst evenly and then adding solvent, based on parts by weight. The viscosity of the encapsulation ink is 10~20 cP.

[0011] In one specific embodiment, the viscosity of the encapsulating ink is 15 cP.

[0012] In one specific embodiment, the encapsulation ink further includes at least one of an antioxidant, an ultraviolet absorber, and a light stabilizer.

[0013] In one specific embodiment, the perovskite quantum dot microarray is composed of any one of CsPbCl3, CsPbBr3, or a mixture of CsPbCl3 and CsPbBr3.

[0014] To improve the above-mentioned technical problems, one technical solution adopted in this application is: to provide a method for repairing a perovskite quantum dot microarray device, used to repair a perovskite quantum dot microarray device prepared by the perovskite quantum dot microarray packaging method as described in any of the above specific embodiments, the method for repairing the perovskite quantum dot microarray device includes: providing the perovskite quantum dot microarray device; heating the perovskite quantum dot microarray device at 80~90℃ for 5~10 minutes.

[0015] To improve the above-mentioned technical problems, one technical solution adopted in this application is: to provide a method for preparing an encapsulation ink, used to implement the perovskite quantum dot microarray encapsulation method as described in any of the above specific embodiments, wherein the method for preparing the encapsulation ink includes: mixing 80-120 parts of matrix resin, 5-20 parts of dynamic covalent crosslinking agent, 3-15 parts of two-dimensional nano barrier filler, 0.5 parts of catalyst, and solvent to obtain an intermediate mixture; stirring the intermediate mixture and then subjecting the intermediate mixture to ultrasonic treatment; and obtaining the encapsulation ink.

[0016] The beneficial effects of this application include: by using the encapsulation method provided in this application, a flexible encapsulation film with dynamic covalent bonds is formed by combining a specific formulation of encapsulation ink with inkjet printing and heat treatment UV curing processes. This film can effectively block water and oxygen permeation and has a certain self-healing ability. It improves the problems of easy cracking and failure of the encapsulation layer, limited barrier ability, and irreversible damage in traditional perovskite quantum dot microarray devices. It can effectively improve the environmental stability of perovskite quantum dot microarray devices, enhance the flexibility and barrier performance of the encapsulation film, and have potential damage repair capabilities, thereby ensuring the stability and service life of perovskite quantum dot microarray devices. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the implementation will be briefly introduced below. Obviously, the drawings described below are some implementations of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0018] Figure 1 is a flowchart illustrating an embodiment of the perovskite quantum dot microarray packaging method of this application. Detailed Implementation

[0019] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of the invention. However, those skilled in the art will understand that the invention can be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, circuits, and methods are omitted so as not to obscure the description of this application with unnecessary detail.

[0020] It should be understood that, when used in this specification and the appended claims, the term "comprising" indicates the presence of the described features, integrals, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.

[0021] It should also be understood that the terminology used in this application specification is for the purpose of describing particular embodiments only and is not intended to limit the application. As used in this application specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise. The terms “first” and “second” are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as “first” or “second” may explicitly or implicitly include at least one of that feature. In the description of this application, “a plurality” means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0022] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0023] Many specific details are set forth in the following description in order to provide a full understanding of this application. However, this application may also be implemented in other ways different from those described herein. Those skilled in the art can make similar extensions without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0024] Perovskite quantum dot microarray devices, with their advantages such as high color purity and tunable emission wavelength, hold significant promise for next-generation display technologies. However, perovskite materials are highly sensitive to water, oxygen, and even light, and their environmental stability issues severely limit their practical application.

[0025] In the encapsulation stage of perovskite quantum dot microarray devices, traditional rigid encapsulation layers such as oxide films are prone to microcracks due to their high material brittleness. These microcracks easily form when the device is subjected to mechanical stress or repeated bending. Once formed, these microcracks provide direct pathways for water vapor and oxygen from the environment, leading to rapid phase separation or oxidative degradation of the perovskite quantum dot material and significant deterioration of the device's photoelectric performance. While flexible polymer encapsulation layers can alleviate stress problems, their large free volume between molecular chains results in insufficient long-term barrier capabilities against water and oxygen, failing to meet high reliability requirements.

[0026] For high-precision perovskite quantum dot microarray devices, each micrometer-scale pixel depends on the integrity of the encapsulation layer. Localized encapsulation failure not only leads to the loss of function of a single pixel but can also affect surrounding areas through thermal diffusion or electric field coupling, causing damage to display uniformity. Furthermore, existing encapsulation technologies lack the ability to repair microscopic damage; once microcracks or interface defects appear, the device's performance and lifespan are significantly affected. Therefore, perovskite quantum dot microarray devices suffer from insufficient environmental stability, susceptibility to encapsulation layer cracking and failure, and irreversible damage in practical applications.

[0027] In order to improve or mitigate the above-mentioned technical problems, the inventors of this application, after long-term research, have proposed at least the following embodiments.

[0028] This application provides a perovskite quantum dot microarray packaging method, referring to Figure 1, which is a schematic flowchart of an embodiment of the perovskite quantum dot microarray packaging method of this application. The perovskite quantum dot microarray packaging method provided in this application may include: S100: providing a perovskite quantum dot microarray and providing packaging ink.

[0029] Based on mass parts, the encapsulation ink is composed of 80-120 parts of matrix resin, 5-20 parts of dynamic covalent crosslinking agent, 3-15 parts of two-dimensional nano barrier filler, 0.5 parts of catalyst, and solvent, which are mixed and uniformly prepared. The dynamic covalent crosslinking agent includes furan-terminated polyurethane oligomers and bismaleimide.

[0030] Perovskite quantum dot microarrays can be prefabricated using various techniques. For example, a perovskite quantum dot layer with a specific pattern can be formed on a substrate using photolithography, or perovskite quantum dots can be transferred to a target area using microcontact printing. The encapsulation ink can be composed of a mixture of multiple components; for example, it can contain only a polymer matrix and a solvent, or a small amount of additives to adjust rheological properties.

[0031] The composition of the encapsulation ink is key to achieving the specific performance of the encapsulation layer. The base resin, as the main material of the encapsulation layer, can be a polymer with good flexibility and adhesion; for example, epoxy resin, acrylic resin, or polyurethane resin can be used.

[0032] Dynamic covalent crosslinking agents include furan-terminated polyurethane oligomers and bismaleimides, which form a crosslinked network through a reversible Diels-Alder reaction, endowing the encapsulation layer with self-healing capabilities. Besides the furan-maleimide system, other types of reversible covalent bonds can also be used, such as disulfide bonds, Schiff base bonds, or borate ester bonds.

[0033] The introduction of two-dimensional nano-barrier fillers aims to improve the water and oxygen barrier properties of the encapsulation layer. For example, alumina nanosheets, boron nitride nanosheets, or clay nanosheets can be selected. Catalysts are used to accelerate or promote cross-linking reactions in the ink; for example, acidic catalysts such as p-toluenesulfonic acid or basic catalysts such as triethylamine can be selected.

[0034] Solvents are used to adjust the viscosity of the encapsulating ink to make it suitable for subsequent printing processes. For example, water, alcohols (such as isopropanol), ketones (such as acetone), or esters (such as ethyl acetate) can be used.

[0035] S200: Uses a high-precision inkjet printing system to print encapsulation ink onto the perovskite quantum dot microarray and its periphery.

[0036] This printing method allows for precise control over the ink deposition location and thickness, ensuring that the encapsulation layer uniformly and completely covers the microarray. Alternatively, other coating techniques can be used, such as slot coating, spin coating, or blade coating, to coat the encapsulation ink onto the microarray surface.

[0037] S300: Heat treatment at 80℃ for 5-10 minutes, followed by heat treatment at 120℃ for 1-3 minutes.

[0038] After ink printing, a step-by-step heat treatment is performed. This step-by-step heat treatment process aims to optimize the cross-linking structure within the encapsulation layer, promote the formation of dynamic covalent bonds, and avoid potential damage to the perovskite quantum dots caused by high temperatures. As an alternative, a single-step heat treatment can also be used, for example, heat treatment can be performed at a fixed temperature (e.g., 100°C) for a certain period of time.

[0039] S400: Irradiate and cure under 365nm ultraviolet light for 30-60 seconds until an encapsulation film is formed on the perovskite quantum dot microarray and its periphery.

[0040] Ultraviolet (UV) light curing can rapidly initiate photopolymerization or photocrosslinking reactions in inks, quickly transforming liquid inks into solid films, thereby improving encapsulation efficiency. Alternatively, other curing methods can be used, such as pure thermal curing or electron beam curing.

[0041] The matrix resin can be polydimethylsiloxane prepolymer, and the solvent is n-heptane. Polydimethylsiloxane prepolymer has flexibility and hydrophobicity, and when used in combination with n-heptane, it can form an encapsulation ink with good flowability and curing properties.

[0042] Optionally, the matrix resin can be an aqueous polyurethane dispersion, and the solvent is a mixture of deionized water and ethanol. Aqueous polyurethane dispersions are environmentally friendly and, when combined with water-ethanol mixed solvents, are suitable for encapsulation applications in aqueous systems.

[0043] For ease of understanding, some key terms in this embodiment are explained below.

[0044] Perovskite quantum dot microarrays refer to micrometer-scale structures composed of perovskite quantum dots with specific geometric arrangements and sizes. These arrays are typically used as the core light-emitting or photosensitive units in optoelectronic devices, and their performance is sensitive to external environmental factors, particularly water and oxygen.

[0045] Encapsulation ink is a liquid material used to form a protective encapsulation layer. This ink is designed to cure and form a thin film with specific physical and chemical properties to isolate perovskite quantum dot microarrays from the external environment.

[0046] Dynamic covalent crosslinking agents are molecules that can undergo reversible bonding and debonding under specific conditions. In this embodiment, the crosslinking agent includes furan-terminated polyurethane oligomers and bismaleimide, which form reversible covalent bonds through the Diels-Alder reaction, thereby endowing the encapsulation layer with self-repairing capabilities.

[0047] Two-dimensional nanobarrier fillers refer to sheet-like materials with nanometer-scale thickness and micrometer-scale lateral dimensions. These fillers can form tortuous diffusion paths in the encapsulation layer, effectively prolonging the time for small molecules such as water and oxygen to penetrate the encapsulation layer, thereby improving the barrier performance of the encapsulation layer.

[0048] A high-precision inkjet printing system is a device capable of precisely jetting tiny droplets to a designated location. Through digital control, this system achieves precise deposition of encapsulation ink on the surface and periphery of a perovskite quantum dot microarray, ensuring the uniformity and integrity of the encapsulation layer.

[0049] Heat treatment is a process that induces or accelerates physical or chemical changes within a material through heating. In this embodiment, heat treatment is used to promote cross-linking reactions in the encapsulation ink, optimizing the structure and properties of the encapsulation film.

[0050] Ultraviolet (UV) curing refers to the process of using UV light of a specific wavelength to initiate photopolymerization or photocrosslinking reactions, rapidly transforming liquid ink into a solid film. This curing method is characterized by high efficiency and low energy consumption.

[0051] Encapsulation films are thin solid layers formed on the surface of perovskite quantum dot microarrays to provide protection and isolation. The performance of these films directly affects the long-term stability and reliability of perovskite quantum dot microarray devices.

[0052] This application proposes a perovskite quantum dot microarray encapsulation method, which aims to form an encapsulation film with flexibility, high barrier properties and self-healing ability through specific material composition and process flow.

[0053] Suppose we need to encapsulate a perovskite quantum dot microarray device for display applications to improve its long-term stability under humid and stressful environments. Traditional encapsulation methods may cause microcracks to form in the encapsulation layer when the device is bent, leading to water and oxygen penetration, resulting in device performance degradation or even failure.

[0054] In this regard, a specific embodiment of the present application proposes an encapsulation method. First, a perovskite quantum dot microarray to be encapsulated is prepared. Simultaneously, an encapsulation ink is prepared. The encapsulation ink is configured to contain 100 parts of polydimethylsiloxane prepolymer as the matrix resin, 20 parts of a dynamic covalent crosslinking agent composed of furan-terminated polyurethane oligomer and bismaleimide, 5 parts of two-dimensional graphene oxide nanosheets as two-dimensional nano-barrier fillers, 0.5 parts of boron trifluoride diethyl ether complex as a catalyst, and an appropriate amount of n-heptane as a solvent, and all components are mixed uniformly.

[0055] Subsequently, using a high-precision inkjet printing system, the prepared encapsulation ink was precisely printed onto the surface and surrounding area of ​​the perovskite quantum dot microarray. Inkjet printing technology ensures that the ink can cover the target area with micron-level precision, forming a uniform liquid ink layer.

[0056] After ink printing, the device undergoes a step-by-step heat treatment. First, the device is heated at 80°C for 7 minutes to promote the initial cross-linking reaction in the ink. Then, the temperature is increased to 120°C and heated at this temperature for another 2 minutes to further optimize the formation of the cross-linking network and enhance the mechanical strength and stability of the encapsulation film.

[0057] Finally, the heat-treated device was exposed to 365nm ultraviolet light for 45 seconds to cure. The ultraviolet light triggered a photopolymerization reaction in the ink, causing the liquid ink to solidify rapidly and form a robust and flexible encapsulation film on the perovskite quantum dot microarray and its surroundings.

[0058] The resulting encapsulation film, due to the flexibility of the matrix resin, can effectively resist external stress and reduce crack formation. The presence of a dynamic covalent crosslinking agent allows the encapsulation film to self-repair when subjected to minor mechanical damage, such as microcracks, by applying appropriate heat to promote the reversible breakage and recombination of furan-maleimide bonds, thus preventing damage accumulation. Two-dimensional graphene oxide nanosheets form meandering paths within the film, significantly extending the distance and time for water and oxygen molecules to permeate, greatly enhancing the barrier properties of the encapsulation layer. High-precision inkjet printing ensures the uniformity and integrity of the encapsulation layer, avoiding localized weak points. Stepwise heat treatment and UV curing work synergistically to optimize the film's structure and performance while ensuring curing efficiency, guaranteeing the long-term stable operation of the perovskite quantum dot microarray device.

[0059] Traditional rigid encapsulation layers, such as oxide films, are prone to microcracks under stress or bending, allowing external water and oxygen to penetrate into the perovskite microarray device. Once damaged, these microcracks are difficult to repair. In contrast, this application introduces dynamic covalent crosslinking agents, such as furan-terminated polyurethane oligomers and bismaleimide, to construct a reversible covalent crosslinking network within the encapsulation film. This network enables the encapsulation film to self-repair through bond breaking and recombination when subjected to mechanical stress or minor damage, effectively preventing the accumulation and propagation of microcracks, thereby significantly improving the durability of the encapsulation layer and the long-term stability of the device.

[0060] Furthermore, while traditional flexible polymer encapsulation layers possess a certain degree of flexibility, their performance in blocking water and oxygen is relatively limited. This application addresses this issue by adding two-dimensional nano-barrier fillers, such as two-dimensional graphene oxide nanosheets, to the encapsulation ink. These nanosheets form highly tortuous diffusion paths within the encapsulation film, significantly extending the distance water and oxygen molecules must travel to penetrate the encapsulation layer, thereby substantially improving the encapsulation layer's water and oxygen barrier performance. This provides significantly stronger protection compared to traditional flexible encapsulation layers that rely solely on the polymer matrix for barrier protection.

[0061] Furthermore, this application employs a high-precision inkjet printing system to precisely print encapsulation ink onto the perovskite quantum dot microarray and its periphery. This precise deposition method ensures that the encapsulation layer can uniformly and completely cover the target area, avoiding localized unevenness or insufficient coverage that may occur with traditional coating methods, thereby improving the reliability of the encapsulation. Simultaneously, the step-by-step heat treatment combined with ultraviolet curing process enables precise control of the crosslinking reaction, ensuring curing efficiency while optimizing the mechanical properties and stability of the film and avoiding potential damage to the quantum dots from high temperatures.

[0062] In summary, the packaging method of this application effectively improves the problems of perovskite quantum dot microarray packaging layers being prone to brittleness under stress, having limited barrier properties, and being subject to irreversible microscopic damage through synergistic optimization of material composition and process flow, providing a reliable packaging improvement solution for the practical application of perovskite microarray devices.

[0063] In some embodiments described above in this application, a packaging method is proposed to protect perovskite quantum dot microarrays. However, during the process of providing the perovskite quantum dot microarray and printing the packaging ink using a high-precision inkjet printing system, the packaging ink may contain water, oxygen, or other substances that may adversely affect the quantum dot microarray, which may lead to failure or performance degradation of the perovskite quantum dot microarray device during the packaging process.

[0064] In this regard, this application further proposes a step of coating the perovskite quantum dot microarray and its periphery with long-chain hydrophobic ligands or an inorganic passivation layer before printing encapsulation ink on the perovskite quantum dot microarray and its periphery using a high-precision inkjet printing system and after providing the perovskite quantum dot microarray.

[0065] Long-chain hydrophobic ligands are organic molecules with relatively long carbon chains and hydrophobic properties, typically containing functional groups at one end that can bind to the surface of perovskite quantum dots. By forming a dense hydrophobic protective layer on the surface of perovskite quantum dots, these ligands effectively prevent direct contact between water molecules and the quantum dots, thereby improving the stability of the quantum dots in humid and hot environments.

[0066] As one approach, long-chain hydrophobic ligands can be aliphatic amine ligands such as oleylamine or octadecylamine, which are adsorbed onto the surface of quantum dots by means of solution impregnation or spin coating.

[0067] As another approach, long-chain hydrophobic ligands can be fatty acid ligands such as oleic acid or caprylic acid, which utilize their carboxyl groups to coordinate with metal ions on the surface of quantum dots to form a hydrophobic protective layer.

[0068] An inorganic passivation layer is a thin film composed of inorganic materials. Its main function is to cover the surface of perovskite quantum dots, forming a physical barrier layer to prevent corrosion from harmful external substances such as water and oxygen. The inorganic passivation layer provides mechanical protection and chemical inertness, effectively preventing water and oxygen penetration, while also passivating defect states on the quantum dot surface, thus improving luminescence efficiency and stability.

[0069] One approach is to grow alumina (Al₂O₃) or titanium oxide (TiO₂) films on the surface of perovskite quantum dot microarrays using atomic layer deposition (ALD) technology. This method enables precise nanoscale thickness control and excellent conformality. Another approach is to prepare silica (SiO₂) or hafnium oxide (HfO₂) films using chemical vapor deposition (CVD) or sputtering to form a dense and uniform inorganic protective layer.

[0070] The coating step in this specific embodiment aims to form a protective coating on the perovskite quantum dot microarray and its surroundings to isolate the quantum dots from potentially harmful components in the subsequent encapsulation ink. This coating can be performed by dip coating, immersing the perovskite quantum dot microarray in a solution containing long-chain hydrophobic ligands or inorganic precursors, and then removing and drying it. Alternatively, it can be performed by spin coating, where a solution is dropped onto the surface of the perovskite quantum dot microarray and uniformly spread to form a thin film by high-speed rotation.

[0071] This specific embodiment introduces a pre-coating step after the perovskite quantum dot microarray is provided and before the encapsulation ink is printed using a high-precision inkjet printing system. This pre-constructs a protective barrier on the surface of the quantum dot microarray. This protective barrier can be a hydrophobic layer formed by long-chain hydrophobic ligands, which effectively repels water molecules from the encapsulation ink, reducing the erosion of the quantum dots by water molecules; or it can be a dense physical barrier layer formed by an inorganic passivation layer, which blocks the intrusion of oxygen and other harmful substances.

[0072] This pre-protection mechanism ensures that the perovskite quantum dot microarray is protected from water and oxygen erosion or chemical damage that may occur during the subsequent encapsulation ink printing and thermal curing processes, thereby significantly reducing the risk of device failure or performance degradation during encapsulation. This pre-coating layer works synergistically with the subsequently formed encapsulation film to provide more comprehensive and reliable protection for the perovskite quantum dot microarray, enhancing the stability of the entire encapsulation method.

[0073] As one specific implementation, after providing the perovskite quantum dot microarray, an oleylamine-toluene solution with a concentration of 1-5 mg / mL can be prepared. The perovskite quantum dot microarray is immersed in this oleylamine-toluene solution for approximately 30 seconds to 2 minutes, allowing oleylamine molecules to be fully adsorbed onto the quantum dot surface. Subsequently, the microarray is removed and gently rinsed with pure toluene to remove excess oleylamine, and then dried in a nitrogen atmosphere or a vacuum oven at 60°C to ensure complete solvent evaporation and strong ligand binding.

[0074] As another specific implementation, after providing the perovskite quantum dot microarray, the microarray can be placed in an atomic layer deposition (ALD) apparatus. At a temperature of 100-150°C, trimethylaluminum (TMA) and water vapor are alternately introduced for 10-50 cycles of deposition, thereby forming a uniform and dense alumina (Al2O3) inorganic passivation layer on the surface of the perovskite quantum dot microarray.

[0075] The above technical solution forms an effective protective barrier on the surface of the quantum dots before the encapsulation ink comes into contact with the perovskite quantum dot microarray. This prevents the quantum dots from being directly exposed to water, oxygen, or other potentially harmful substances in the encapsulation ink during the encapsulation process. This significantly enhances the stability of the perovskite quantum dot microarray, effectively preventing device failure or performance degradation caused by ink during encapsulation, thereby improving the reliability of the encapsulation method and extending the lifespan of the perovskite microarray devices.

[0076] In some embodiments described above, heating allows the DA bonds of furan and maleimide to undergo a reverse reaction (retro-DA) dissociation at a moderate temperature (approximately 110-130°C), and then recombine upon cooling, thereby achieving the reorganization and repair of the network topology, i.e., macroscopically repairing cracks in the encapsulation layer. However, during its implementation, increasing the temperature may lead to the failure or efficiency reduction of the perovskite microarray, affecting the performance of the perovskite microarray device.

[0077] In this regard, this application further proposes that the catalyst may specifically include either boron trifluoride diethyl ether complex or trifluoromethanesulfonate.

[0078] In dynamic covalent chemical reactions, a catalyst is a substance that can accelerate the reaction rate without being consumed. For the reverse reaction (retro-DA) dissociation process of the dynamic covalent bond (DA bond) formed between furan and maleimide in encapsulation ink, the introduction of a suitable catalyst can significantly reduce the activation energy required for the reaction, thereby achieving rapid dissociation of the DA bond at a lower temperature.

[0079] Among them, boron trifluoride diethyl ether complex is a commonly used Lewis acid catalyst. It can enhance the electrophilicity of maleimide components by coordinating with electron acceptor sites such as carbonyl groups, thereby promoting the breaking of DA bonds at lower temperatures.

[0080] Trifluoromethanesulfonates, such as certain metal trifluoromethanesulfonates (e.g., scandium trifluoromethanesulfonate), also act as Lewis acid catalysts, activating reactants through a similar mechanism to accelerate the reverse reaction. The presence of these catalysts allows the molecular network of the encapsulated film to achieve efficient dynamic recombination within a temperature range harmless to the perovskite quantum dot microarray when repair is required.

[0081] By introducing specific catalysts, namely boron trifluoride diethyl ether complexes or trifluoromethanesulfonate, into the encapsulation ink, the activation energy required for the reverse (retro-DA) dissociation of the dynamic covalent bond (DA bond) between furan and maleimide was significantly reduced. When cracks appear in the encapsulation film and need repair, these catalysts can promote the rapid dissociation of the DA bond at relatively low temperatures. When the encapsulation film is damaged and exposed to an appropriate repair temperature, the presence of the catalyst allows the DA bond to break rapidly, thereby allowing the polymer molecular chain segments at the crack interface to acquire sufficient fluidity and interdiffusion. Subsequently, the free furan groups and maleimide groups re-meet at the new interface and, upon cooling or removal of the heat source, re-form stable DA covalent bonds, achieving self-repair of the encapsulation film. This catalytic effect ensures that the repair process can be carried out efficiently at lower temperatures without impairing the performance of the perovskite quantum dot microarray, avoiding the problems of perovskite material degradation or efficiency reduction that may occur due to high-temperature repair.

[0082] As a specific implementation method, boron trifluoride diethyl ether complex can be used as a catalyst in the preparation of the encapsulation ink. After the matrix resin, dynamic covalent crosslinking agent, two-dimensional nano-barrier filler, and solvent are mixed evenly, the boron trifluoride diethyl ether complex is added at a ratio of 0.5 parts by mass. This catalyst maintains its activity after the encapsulation ink has cured to form an encapsulation film. When the encapsulation film develops microcracks due to external stress, during repair operations, such as through localized heating, the boron trifluoride diethyl ether complex can effectively catalyze the reverse dissociation of the DA bond between furan and maleimide. This allows the molecular network of the encapsulation film to dynamically reorganize at a lower temperature, thereby promoting crack closure and restoring the integrity of the encapsulation layer.

[0083] By introducing boron trifluoride diethyl ether complex or trifluoromethanesulfonate as a catalyst into the encapsulation ink, the temperature required for the dynamic covalent bond dissociation in the encapsulation film is significantly reduced, and the reaction rate is accelerated. This allows perovskite quantum dot microarray devices to operate at temperatures far below the traditional reverse reaction temperature when repairing cracks in the encapsulation layer, effectively avoiding potential damage to the perovskite material from high temperatures, such as efficiency reduction or structural failure. This not only ensures the self-healing capability of the encapsulation film but also mitigates the negative impact of the repair process on the performance of the perovskite quantum dot microarray, improving the long-term stability and reliability of the device and extending its lifespan.

[0084] In some of the solutions described above in this application, a matrix resin and a solvent are proposed to encapsulate perovskite quantum dot microarrays. However, when using polydimethylsiloxane prepolymer as the matrix resin and n-heptane as the solvent, existing catalysts may not be able to effectively promote the curing reaction or may interfere with the chemical stability of the quantum dots, resulting in incomplete curing of the encapsulation layer or affecting the long-term reliability of the device.

[0085] In this regard, this application further proposes that when the matrix resin is a polydimethylsiloxane prepolymer and the solvent is n-heptane, the catalyst may include a platinum catalyst.

[0086] The matrix resin is a polydimethylsiloxane prepolymer, which, as the main component of the encapsulation ink, provides excellent flexibility, heat resistance, weather resistance, chemical inertness, and biocompatibility, providing reliable physical protection for the perovskite quantum dot microarray.

[0087] For example, polydimethylsiloxane prepolymers with different molecular weights or functional group types, such as hydroxyl-terminated polydimethylsiloxane or vinyl-terminated polydimethylsiloxane, can be selected to adapt to different crosslinking mechanisms and the performance requirements of the final encapsulation layer.

[0088] Alternatively, a polydimethylsiloxane prepolymer with a specific branched structure may be used to further adjust the rheology and mechanical strength of the encapsulation ink after curing.

[0089] The solvent is n-heptane, which, as a non-polar aliphatic hydrocarbon solvent, has good compatibility with polydimethylsiloxane prepolymer. It can effectively dissolve the solid components in the encapsulation ink and adjust the viscosity of the ink, making it suitable for high-precision inkjet printing.

[0090] Furthermore, in addition to pure heptane, isomeric heptane or mixtures of heptane with other non-polar solvents such as cyclohexane and toluene can also be used, as long as they have good compatibility with polydimethylsiloxane prepolymer and moderate volatility, to ensure the stability of the printing process and minimize solvent residue after curing.

[0091] Based on the above selection of matrix resin and solvent, the catalyst can include a platinum catalyst. Platinum catalysts are commonly used and highly efficient catalysts in hydrosilylation reactions, capable of promoting cross-linking reactions between compounds containing silicon-hydrogen bonds and compounds containing carbon-carbon double bonds. In polydimethylsiloxane systems, platinum catalysts can effectively accelerate the curing process of prepolymers, forming stable cross-linked networks.

[0092] Alternatively, different forms of platinum catalysts can be used, such as caster catalysts (platinum-divinyltetramethyldisiloxane complex), platinum-cyclovinylsiloxane complexes, or supported platinum catalysts.

[0093] Furthermore, different platinum catalysts with varying activities can be selected and their addition amounts adjusted according to the required curing speed and temperature to precisely control the progress of the curing reaction.

[0094] This application presents a highly efficient and stable encapsulation ink system by using polydimethylsiloxane prepolymer as the matrix resin, n-heptane as the solvent, and introducing a platinum catalyst. In the perovskite quantum dot microarray encapsulation method, a perovskite quantum dot microarray and an encapsulation ink are first provided. The polydimethylsiloxane prepolymer in the encapsulation ink provides the basic flexibility and chemical stability required for the encapsulation layer, while n-heptane, as the solvent, ensures good flowability and uniformity of the ink in the inkjet printing system, enabling the encapsulation ink to be accurately printed on the perovskite quantum dot microarray and its periphery.

[0095] This specific catalyst selection ensures that the curing reaction proceeds fully in the polydimethylsiloxane prepolymer and n-heptane system, forming a dense and uniform encapsulation film, thus effectively avoiding encapsulation layer defects caused by incomplete curing. Simultaneously, the introduction of a platinum catalyst, without affecting the chemical stability of the perovskite quantum dots, promotes the rapid formation of the encapsulation layer, providing a stable matrix environment for the subsequent dynamic covalent crosslinking agent. This allows the agent to better exert its self-healing function, further improving the overall performance of the encapsulation layer and the long-term reliability of the device.

[0096] As a specific implementation method, when preparing the encapsulation ink, a vinyl-terminated polydimethylsiloxane prepolymer can be selected as the matrix resin, which has good reactivity and flexibility. High-purity n-heptane can be used as the solvent to ensure the purity of the ink and the stability of the printing process. A castor catalyst can be selected, which exists in the form of a platinum-divinyltetramethyldisiloxane complex and is dissolved in solvents such as xylene for easy addition and dispersion.

[0097] In formulating the encapsulation ink, vinyl-terminated polydimethylsiloxane prepolymer, dynamic covalent crosslinking agent, two-dimensional nano-barrier filler, caster catalyst, and n-heptane are mixed uniformly according to a predetermined mass ratio. Subsequently, this encapsulation ink is precisely printed onto a perovskite quantum dot microarray using a high-precision inkjet printing system. In the subsequent heat treatment and UV curing steps, the caster catalyst efficiently catalyzes the crosslinking reaction of the polydimethylsiloxane prepolymer, rapidly forming an encapsulation film with excellent performance.

[0098] Through the above technical solution, this application effectively improves the problem of low curing efficiency or negative impact on quantum dot stability that may be caused by existing catalysts when using polydimethylsiloxane prepolymer as the matrix resin and n-heptane as the solvent. The introduction of platinum catalyst significantly improves the curing efficiency of the encapsulation ink, ensuring rapid and complete formation of the encapsulation film, thereby obtaining a dense, uniform encapsulation layer with good flexibility. This not only enhances the physical protection and water and oxygen barrier capabilities of the encapsulation layer for the perovskite quantum dot microarray, but also avoids encapsulation layer defects and quantum dot performance degradation that may be caused by incomplete curing, greatly improving the environmental stability and long-term reliability of perovskite microarray devices.

[0099] In some of the solutions described above in this application, encapsulation inks are proposed for forming encapsulation films on perovskite quantum dot microarrays. However, in the implementation process, a wide range of composition ratios of the encapsulation ink may affect the printing accuracy and coating uniformity of the high-precision inkjet printing system, thereby reducing the quality and reliability of the encapsulation film.

[0100] In this regard, this application further proposes an encapsulation ink, which, by weight, is prepared by mixing 100 parts of matrix resin, 20 parts of dynamic covalent crosslinking agent, 5 parts of two-dimensional nano barrier filler, and 0.5 parts of catalyst evenly and then adding solvent, and the viscosity of the encapsulation ink is 10~20 cP.

[0101] The matrix resin, as the main component of the encapsulation ink, provides the flexibility, adhesion, and mechanical strength of the encapsulation film. Its role is to form a continuous polymer matrix, uniformly dispersing other components within it, and ultimately curing to form a protective layer. The matrix resin can be a polymer with good flexibility and chemical stability, such as polydimethylsiloxane prepolymer, which has excellent weather resistance and water / oxygen barrier properties. Alternatively, an environmentally friendly waterborne polyurethane dispersion can be used, which has good film-forming properties and mechanical properties.

[0102] Dynamic covalent crosslinking agents play a crucial role in encapsulation inks. They can form a reversible covalent network during the curing process, endowing the encapsulation film with self-healing capabilities and excellent mechanical properties. These crosslinking agents typically contain two or more functional groups capable of reversible reactions, such as furan-terminated polyurethane oligomers and bismaleimides. Under heating conditions, they can undergo a Diels-Alder reaction to form a crosslinked structure, while under other conditions, they can dissociate, thereby achieving film repair.

[0103] The introduction of two-dimensional nano-barrier fillers aims to significantly improve the water and oxygen barrier performance of encapsulation films. These fillers typically possess a high aspect ratio and a layered structure, enabling them to form tortuous diffusion paths within the polymer matrix. This effectively extends the permeation paths of water and oxygen molecules, thereby reducing the permeation rate. For example, exfoliated graphene, boron nitride nanosheets, or MXene can be selected as two-dimensional nano-barrier fillers.

[0104] Catalysts are used in encapsulation inks to accelerate dynamic covalent crosslinking reactions, ensuring efficient formation of crosslinked networks within a set heat treatment time. The choice of catalyst needs to match the reaction system of the dynamic covalent crosslinking agent; for example, platinum catalysts can be used for hydrosilylation reaction systems.

[0105] The preparation process of encapsulated inks emphasizes the thorough and uniform mixing of all components, which is fundamental to ensuring stable ink performance and consistent print quality. First, solid or high-viscosity components are thoroughly mixed to ensure uniform dispersion within the system and prevent agglomeration. Then, an appropriate amount of solvent is added to adjust the ink's viscosity to meet the requirements of high-precision inkjet printing systems, while simultaneously ensuring stable dispersion of all components in the solution to prevent precipitation or stratification.

[0106] The viscosity of the encapsulation ink is a key parameter affecting inkjet printing performance. Maintaining the viscosity within a specific range of 10-20 cP ensures good ink flow within the printhead, preventing droplet scattering or satellite droplet formation due to excessively low viscosity, and avoiding nozzle clogging or droplet formation difficulties due to excessively high viscosity. This viscosity range facilitates precise droplet ejection and uniform spreading on the substrate, resulting in a high-quality encapsulation film.

[0107] This specific embodiment optimizes the performance of the encapsulating ink in high-precision inkjet printing by precisely defining the mass fractions and overall viscosity of each component. Using 100 parts of matrix resin as the main component of the ink provides the basic flexibility, adhesion, and mechanical strength required for the encapsulation film, ensuring stable film formation. 20 parts of dynamic covalent crosslinking agent form a reversible covalent network during curing, endowing the encapsulated film with self-healing capabilities while enhancing its overall mechanical properties and durability. 5 parts of two-dimensional nano-barrier filler form tortuous diffusion paths within the matrix resin, effectively extending the distance for water and oxygen permeation, thereby significantly improving barrier performance. The addition of 0.5 parts of catalyst precisely controls the rate of the dynamic covalent crosslinking reaction, ensuring efficient and controllable crosslinking during heat treatment, avoiding the negative impact of excessively fast or slow curing on print quality and film performance.

[0108] By adding an appropriate amount of solvent, the viscosity of the encapsulated ink can be precisely controlled within the range of 10~20 cP. This specific viscosity range gives the ink ideal rheological properties in high-precision inkjet printing systems, enabling precise ejection, stable flight, and uniform spreading of ink droplets, effectively avoiding problems such as nozzle clogging, ink droplet scattering, or uneven coating.

[0109] By precisely controlling the component ratios and optimizing the viscosity, this solution ensures the stability, accuracy, and uniformity of the encapsulation ink during the printing process, thereby forming a high-quality, highly reliable encapsulation film. This effectively improves the problem of unstable viscosity caused by the wide composition range of traditional encapsulation inks, which in turn affects printing accuracy and film quality.

[0110] In some of the solutions described above in this application, a viscosity range for the encapsulation ink is proposed to ensure the feasibility of inkjet printing and the formation of the encapsulation film. However, a wide viscosity range may cause ink viscosity fluctuations, affecting printing accuracy and film uniformity, thereby reducing device stability and repair effect.

[0111] In this regard, this application further proposes that the viscosity of the encapsulation ink is 15 cP.

[0112] The viscosity of encapsulation ink is a measure of fluid flow resistance. For inkjet printing, viscosity directly affects droplet formation, jetting stability, flight trajectory, and spreading behavior on the substrate. Precisely setting the viscosity of the encapsulation ink to 15 cP aims to optimize the ink's rheological properties, enabling it to exhibit ideal jetting performance and deposition uniformity during inkjet printing.

[0113] Alternatively, a viscosity of 15 cP can be achieved and maintained by precisely controlling the types and proportions of each component in the encapsulation ink formulation and combining it with a precise mixing process.

[0114] The solution proposed in this application precisely controls the viscosity of the encapsulation ink to 15 cP. This, combined with a high-precision inkjet printing system and specific encapsulation ink components, ensures stable droplet formation and accurate ejection, avoiding printing inconsistencies caused by viscosity fluctuations. During subsequent heat treatment and UV curing, the uniformly deposited ink layer forms a dense and uniform encapsulation film, effectively blocking water and oxygen and improving the environmental stability of the perovskite quantum dot microarray device.

[0115] By employing the aforementioned technical solution, the viscosity of the encapsulation ink is precisely controlled at 15 cP, mitigating the printing inconsistencies caused by a wide viscosity range and ensuring high precision and reliability in the encapsulation process. This specific value optimizes the ink's flowability and deposition characteristics in the inkjet printing system, avoiding printing unevenness or defects caused by viscosity variations. This results in the formation of a more uniform and denser encapsulation film on the perovskite quantum dot microarray, significantly improving the device's environmental stability and long-term reliability, as well as enhancing the overall quality and repairability of the device.

[0116] Traditional perovskite quantum dot microarray encapsulation methods may lack antioxidant and UV resistance when using encapsulation inks to encapsulate perovskite quantum dot microarrays, causing the encapsulation film to degrade easily due to environmental factors during UV curing and subsequent long-term use.

[0117] In response, this application proposes a method for encapsulating perovskite quantum dot microarrays, wherein the encapsulation ink further includes at least one of an antioxidant, an ultraviolet absorber, and a light stabilizer.

[0118] Antioxidants are chemical substances that can inhibit or delay the oxidative degradation of polymer materials. In encapsulation inks and the final encapsulation films, the main role of antioxidants is to capture free radicals, thereby interrupting the oxidation chain reaction and preventing molecular chain breakage, cross-linking, or color changes caused by factors such as oxygen, heat, or light.

[0119] Specifically, antioxidants can be implemented as hindered phenolic antioxidants, such as pentaerythritol tetrakis(β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate) (Irganox 1010) or 2,6-di-tert-butyl-4-methylphenol (BHT). They can also be phosphate ester antioxidants, such as tris(2,4-di-tert-butylphenyl) phosphite (Irgafos 168).

[0120] Ultraviolet (UV) absorbers are compounds that selectively absorb ultraviolet radiation and convert its energy into harmless heat or fluorescence. In perovskite quantum dot microarray encapsulation, UV absorbers effectively block harmful UV light from reaching the perovskite quantum dots and the encapsulation material itself, thereby protecting the optical properties of the quantum dots from attenuation due to UV irradiation and preventing photoaging of the encapsulation material.

[0121] Specifically, UV absorbers may include benzotriazole UV absorbers, such as 2-(2H-benzotriazole-2-yl)-4,6-di-tert-pentylphenol (Tinuvin 328). They may also include benzophenone UV absorbers, such as 2-hydroxy-4-n-octyloxybenzophenone (UV-531).

[0122] Light stabilizers are additives that can inhibit or delay the degradation of polymer materials under light exposure. Unlike UV absorbers, which mainly function by absorbing ultraviolet light, light stabilizers typically stabilize materials through mechanisms such as capturing free radicals, quenching excited-state molecules, or decomposing hydrogen peroxides, thereby extending the lifespan and performance stability of encapsulated films under long-term light exposure.

[0123] Specifically, light stabilizers may include hindered amine light stabilizers (HALS), such as bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate (Tinuvin 770). Nickel complex light stabilizers may also be included, such as nickel salt of 2,2'-thiobis(4-tert-octylphenol).

[0124] The present application proposes a solution that synergizes with the basic perovskite quantum dot microarray encapsulation method by introducing antioxidants, UV absorbers, and / or light stabilizers into the encapsulation ink. Based on the encapsulation ink being a homogeneous mixture of matrix resin, dynamic covalent crosslinking agent, two-dimensional nano-barrier filler, catalyst, and solvent, these additives play a crucial role in ink printing, heat treatment, UV curing, and the long-term use of the device.

[0125] Specifically, after printing encapsulation ink onto the perovskite quantum dot microarray and its periphery using a high-precision inkjet printing system, the antioxidants in the ink effectively inhibit oxidation reactions during exposure to air, maintaining the stability of its components. Subsequently, during heat treatment at 80°C and 120°C, and during curing under 365nm ultraviolet light to form the encapsulation film, the ultraviolet absorber absorbs harmful ultraviolet radiation, protecting the perovskite quantum dots from photodegradation and preventing photoaging of polymer components such as the matrix resin and dynamic covalent crosslinking agent. The light stabilizer further enhances the long-term stability of the encapsulation film under light conditions through mechanisms such as free radical capture. The introduction of these additives results in an encapsulation film that not only possesses the excellent mechanical and barrier properties provided by the dynamic covalent crosslinking agent and two-dimensional nano-barrier filler, but also resists oxidation, ultraviolet radiation, and photodegradation, thereby significantly improving the environmental stability and lifespan of the perovskite quantum dot microarray device.

[0126] Through the above technical solution, in the perovskite quantum dot microarray encapsulation method, the encapsulation ink significantly enhances the environmental stability of the encapsulation film by introducing antioxidants, UV absorbers, and light stabilizers. This effectively improves the problem of the encapsulation film being susceptible to degradation by environmental factors during UV curing and long-term use, avoiding brittleness and failure of the encapsulation layer due to oxidation, UV radiation, or light exposure. Ultimately, this solution can significantly improve the durability and reliability of perovskite quantum dot microarray devices, extend their service life, and overcome key problems in traditional encapsulation technologies such as poor environmental stability, easy brittleness and failure of the encapsulation layer, and irreversible microscopic damage, thus promoting the practical application of perovskite microarray devices.

[0127] In some of the solutions described above in this application, perovskite quantum dot microarrays are proposed for encapsulation. However, in this process, the lack of specified composition may lead to poor encapsulation stability or compatibility issues. For example, perovskite quantum dots with different compositions have different sensitivities to environmental factors such as water and oxygen permeation, which can easily cause local failure or irreversible microscopic damage to the encapsulation layer, thereby affecting the overall reliability and repairability of the device.

[0128] In this specific embodiment, it is further proposed that the composition of the perovskite quantum dot microarray is any one of CsPbCl3, CsPbBr3, or a mixture of CsPbCl3 and CsPbBr3.

[0129] Perovskite quantum dot microarrays refer to the existence of nanoscale semiconductor materials with perovskite crystal structures arranged in a regular pattern. Due to their excellent optoelectronic properties such as high quantum efficiency, narrow emission spectrum, and tunable emission wavelength, they are widely used in displays, lighting, and other fields. CsPbCl3 is a completely inorganic lead halide perovskite quantum dot that typically emits light in the blue spectral region and exhibits good thermal and chemical stability. It can be prepared by various methods, including hot-injection, ligand-assisted redeposition, or ion exchange. CsPbBr3 is also a completely inorganic lead halide perovskite quantum dot, which typically emits light in the green spectral region and possesses excellent photoluminescence quantum efficiency and stability. Its preparation methods are similar to CsPbCl3, including hot-injection, ligand-assisted redeposition, and ion exchange. A mixture of CsPbCl3 and CsPbBr3 refers to the combined use of these two perovskite quantum dots with different compositions, aiming to achieve a wider spectral coverage or specific spectral modulation effects. The mixing method can be to form a solid solution by precisely controlling the proportion of halogen precursors during the synthesis process, or to synthesize them separately and then physically mix them.

[0130] This application addresses the encapsulation compatibility and stability issues arising from unspecified composition by specifically defining the composition of the perovskite quantum dot microarray. By limiting the composition of the perovskite quantum dot microarray to CsPbCl3, CsPbBr3, or mixtures thereof, these all-inorganic lead halide perovskite quantum dots possess excellent intrinsic stability and resistance to water and oxygen, providing a solid foundation for encapsulation. These specifically composed perovskite quantum dots exhibit good chemical compatibility with the matrix resin and dynamic covalent crosslinking agent in the encapsulation ink. This good compatibility facilitates the formation of a uniform and dense encapsulation film on the surface of the perovskite quantum dot microarray, effectively reducing interface defects and stress concentration. During heat treatment and UV curing, the dynamic covalent crosslinking agent in the encapsulation ink reacts to form a self-healing crosslinking network, while two-dimensional nano-barrier fillers further enhance the water and oxygen barrier properties of the encapsulation film. Because the composition of the perovskite quantum dot microarray is optimized, its bonding with the encapsulation film is stronger, and it is less prone to delamination or microcracks, thereby effectively inhibiting the penetration of external water and oxygen and improving the long-term stability and reliability of the device.

[0131] As a specific implementation method, CsPbBr3 quantum dots can be selected as the luminescent material when preparing perovskite quantum dot microarrays. Specifically, CsPbBr3 quantum dots can be synthesized by thermal injection, then dispersed in a suitable solvent, and formed into a regularly arranged microarray structure using micro-nano fabrication techniques.

[0132] Optionally, to achieve broader spectral coverage, a mixed quantum dot microarray of CsPbCl3 and CsPbBr3 can be prepared. Specifically, this can be achieved by separately synthesizing CsPbCl3 and CsPbBr3 quantum dots and then mixing them in a specific ratio to form a microarray, or by precisely controlling the ratio of halogen precursors during synthesis to directly synthesize CsPb(ClxBr1-x)3 solid solution quantum dots and then preparing them into a microarray.

[0133] For example, a perovskite quantum dot microarray primarily used for green emission can be fabricated, its composition being pure CsPbBr3. Alternatively, a perovskite quantum dot microarray for achieving broad spectral coverage can be fabricated, its composition being a mixture of CsPbCl3 and CsPbBr3, wherein CsPbCl3 primarily contributes to blue emission and CsPbBr3 primarily contributes to green emission.

[0134] Through the above technical solution, this application specifies that the composition of the perovskite quantum dot microarray is CsPbCl3, CsPbBr3, or a mixture thereof. These specific perovskite quantum dots exhibit excellent intrinsic stability and good compatibility with the encapsulation ink. This allows the encapsulation film to form a tighter and more stable interface bond with the perovskite quantum dot microarray, effectively reducing interface defects and stress concentration, thereby lowering the risk of microcracks or localized failures in the encapsulation layer. Simultaneously, these all-inorganic perovskite quantum dots themselves have good resistance to water and oxygen. Combined with the sealing encapsulation film formed by the encapsulation ink, they can more effectively block the penetration of external water and oxygen, significantly improving the environmental stability and long-term reliability of the perovskite quantum dot microarray device. Furthermore, due to the enhanced integrity and stability of the encapsulation layer, the overall durability of the device is improved, providing a more solid foundation for subsequent repair operations.

[0135] In traditional perovskite quantum dot microarray devices, if a local failure occurs in the encapsulation layer, the entire pixel may fail and is difficult to repair.

[0136] To address this issue, this application proposes a method for repairing perovskite microarray devices fabricated using a perovskite quantum dot microarray encapsulation method. The method may include: providing the perovskite microarray device; and heating the perovskite microarray device at 80-90°C for 5-10 minutes.

[0137] This application proposes a technique for restoring localized damage or failure of the encapsulation layer in perovskite microarray devices during service. Its core lies in restoring the device's performance and function through external intervention, thereby extending its lifespan. This repair method is not universally applicable to all perovskite devices, but specifically refers to perovskite microarray devices encapsulated with specific encapsulation inks (containing dynamic covalent crosslinking agents). This limitation ensures the compatibility of the repair mechanism with the encapsulation material, enabling subsequent repair operations to effectively activate reversible reactions within the encapsulation layer, thereby achieving self-healing of the damage.

[0138] Providing perovskite microarray devices to be repaired is a prerequisite for the repair process, and the aim is to obtain these devices. These devices can be products found to be defective on the production line, or devices that have experienced performance degradation or partial failure after a period of use. Providing methods can include retrieving them from a warehouse, disassembling them from equipment, or directly screening for defects at the end of the production line.

[0139] Heating the perovskite microarray device at 80–90°C for 5–10 minutes is the core operation of this repair method. The purpose of heating is to provide sufficient energy to activate the reversible reaction of the dynamic covalent crosslinking agent in the encapsulation layer. The temperature range of 80–90°C and the time of 5–10 minutes are optimized conditions designed to ensure the effective breaking and reconstruction of dynamic covalent bonds while avoiding thermal damage or performance degradation to the perovskite quantum dots themselves. Various heating methods can be used, such as hot plate heating, oven heating, infrared heating, or localized heating with a hot air gun.

[0140] The solution in this application activates the reversible properties of dynamic covalent bonds in the encapsulation layer through a specific heat treatment process, thereby repairing local damage and restoring device function.

[0141] Specifically, this repair method is used to repair perovskite microarray devices fabricated using a perovskite quantum dot microarray encapsulation method. This feature ensures compatibility between the repair object and the encapsulation method, avoiding repair failure due to incompatibility of encapsulation materials. After providing the perovskite microarray device to be repaired, the device is heated at 80-90°C for 5-10 minutes. This heating condition, with precise temperature and time control, activates the reversible reaction of the dynamic covalent crosslinking agent in the encapsulation layer. In the encapsulation film formed by the curing of the encapsulation ink, furan-terminated polyurethane oligomers and bismaleimide form a crosslinked network through a reversible Diels-Alder reaction. When the encapsulation film develops microcracks due to stress or bending, these dynamic covalent bonds dissociate under appropriate heating conditions, allowing the polymer segments to gain fluidity. During the heating process of 5-10 minutes, the dissociated polymer segments can rearrange and fill the microcrack area. As heating continues, the dissociated dynamic covalent bonds reform, thereby achieving self-healing of the microcracks and restoring the integrity and barrier properties of the encapsulation film. This repair mechanism allows the encapsulation layer to be repaired through simple heat treatment when local failures occur, significantly improving the reliability and lifespan of perovskite microarray devices.

[0142] As a specific implementation method, when a perovskite microarray device develops visible microcracks on the surface of its encapsulation film after long-term use, or when electrical testing reveals a decline in its barrier performance, leading to device performance degradation, this method can be used for repair.

[0143] For example, the faulty perovskite microarray device can be removed from its application environment and placed on a clean, flat heating platform. The heating platform is set to 85°C and maintained for 7 minutes. During heating, the dynamic covalent crosslinking agent in the encapsulation film undergoes a reversible chemical reaction, causing the encapsulation material to reflow and bond at the microscopic level. After heating, the device is removed from the heating platform and allowed to cool naturally to room temperature. Upon cooling, the dynamic covalent bonds in the encapsulation film reform a stable crosslinked network, effectively repairing the original microcracks and restoring the integrity of the encapsulation film and its barrier properties against water and oxygen. The repaired device can then be retested to verify that its function has been restored.

[0144] This application provides an effective repair method for perovskite microarray devices through the above technical solution, improving upon the technical challenge of repairing traditional perovskite device encapsulation layers once they fail. This method utilizes the reversible properties of the dynamic covalent crosslinking agent in the encapsulation layer, achieving self-healing of microcracks in the encapsulation film through simple heat treatment, significantly improving the reliability and environmental stability of perovskite microarray devices. This not only extends the device's lifespan and reduces maintenance costs but also avoids the complete device failure due to localized failures, which is of great significance for the practical application of perovskite microarray devices.

[0145] This application proposes a method for preparing encapsulation ink, which includes: Step 1: mixing 80-120 parts of matrix resin, 5-20 parts of dynamic covalent crosslinking agent, 3-15 parts of two-dimensional nano barrier filler, 0.5 parts of catalyst and solvent to obtain an intermediate mixture.

[0146] Step 2: After stirring the intermediate mixture, the intermediate mixture is subjected to ultrasonic treatment.

[0147] Step 3: Obtain the encapsulation ink.

[0148] The method for preparing this encapsulation ink first involves physically mixing the matrix resin, dynamic covalent crosslinking agent, two-dimensional nano barrier filler, catalyst, and solvent according to a preset mass ratio to form a preliminary homogeneous mixture.

[0149] Step 2 aims to promote the uniform dispersion of the components in the intermediate mixture, especially for liquid and soluble solid components. By using mechanical force, the components are thoroughly mixed, reducing macroscopic inhomogeneities and ensuring that all components are in full contact before subsequent processing. This lays the foundation for subsequent stirring and ultrasonic treatment and avoids local concentrations that are too high or too low.

[0150] For example, the components can be added sequentially to a mixing container and initially mixed using a planetary mixer, a manual stirring rod, or a low-speed mechanical mixer.

[0151] Alternatively, an automated batching system can be used to precisely control the amount of each component added via metering pumps or weighing systems, and to perform preliminary cyclic mixing during the addition process. Subsequently, the intermediate mixture is stirred.

[0152] Alternatively, a magnetic stirrer can be used, which drives the stir bar to rotate at the bottom of the container by magnetic force, generating eddies to fully mix the liquid.

[0153] Alternatively, mechanical agitators, such as paddle agitators, anchor agitators, or dispersion disc agitators, can be used to apply shear force to the mixture through the rotation of the agitator blades, thereby achieving efficient mixing.

[0154] Following stirring, the intermediate mixture is further subjected to ultrasonic treatment. Step three utilizes the cavitation and mechanical effects of ultrasound to efficiently disperse particles in the intermediate mixture, breaking down agglomerates and ensuring their uniform distribution within the solvent and matrix resin. This is crucial for improving ink stability, preventing sedimentation, ensuring smooth inkjet printing, and achieving the density and barrier properties of the final encapsulation film.

[0155] For example, an ultrasonic homogenizer can be used, with its probe directly inserted into the intermediate mixture. High-frequency vibrations generate strong cavitation, achieving efficient dispersion. Alternatively, an ultrasonic cleaning tank can be used, placing the container holding the intermediate mixture inside. Transducers on the bottom or sidewalls of the tank generate ultrasonic waves to indirectly treat the mixture.

[0156] In the encapsulation ink preparation method provided in this specific embodiment, the problem of uneven dispersion of ink components in the traditional preparation process is effectively improved through a series of synergistic steps. First, the matrix resin, dynamic covalent crosslinking agent, two-dimensional nano barrier filler, catalyst, and solvent are mixed in precise mass proportions to form an intermediate mixture, ensuring the accurate ratio of each key component and laying the material foundation for subsequent fine processing.

[0157] Furthermore, the intermediate mixture is stirred to provide mechanical shear force, promoting the full dissolution and uniform distribution of the liquid and soluble components, thus initially eliminating macroscopic inhomogeneities. Based on this, the stirred intermediate mixture is further subjected to ultrasonic treatment. Utilizing the cavitation effect and microjets of ultrasound, the agglomerates of the two-dimensional nano-barrier filler can be effectively broken down, achieving uniform nanoscale dispersion in the matrix resin and solvent, preventing filler sedimentation and re-agglomeration.

[0158] This progressive "mixing-stirring-ultrasonication" process, with each step interconnected, provides optimized initial conditions for the next, ultimately ensuring high uniformity and stability of the encapsulation ink. The resulting encapsulation ink exhibits uniform component distribution and stable viscosity, significantly improving the printing accuracy of subsequent high-precision inkjet printing systems and the uniformity of the encapsulation film. This not only optimizes the performance of the encapsulation ink itself but also ensures that the encapsulation film prepared using this ink provides excellent barrier properties and repair capabilities, thereby effectively enhancing the environmental stability and reliability of perovskite quantum dot microarray devices.

[0159] As a specific implementation method, the preparation of the encapsulation ink can be carried out according to the following steps: In a clean glass beaker, accurately weigh 100 parts of polydimethylsiloxane prepolymer as the matrix resin, then add 20 parts of a mixture of furan-terminated polyurethane oligomer and bismaleimide as a dynamic covalent crosslinking agent, then add 5 parts of two-dimensional nano-alumina sheets as two-dimensional nano-barrier fillers, and 0.5 parts of boron trifluoride diethyl ether complex as a catalyst. Add an appropriate amount of n-heptane as a solvent to wet all components. Place the beaker on a magnetic stirrer and stir at a medium speed for about 30 minutes to ensure that all liquid and soluble components are initially mixed evenly, forming a milky white or translucent intermediate mixture. After stirring, transfer the beaker to an ultrasonic cleaning tank and sonicate at room temperature for about 1 hour. During the ultrasonic treatment, the mixture can be observed to become more homogeneous, with no obvious particle precipitation or stratification. After the ultrasonic treatment, an encapsulation ink with good dispersibility and stability is obtained.

[0160] The above-described method for preparing encapsulating ink effectively improves upon traditional methods that address issues such as uneven ink component distribution and unstable viscosity due to incomplete mixing or poor dispersion. Specifically, by first performing preliminary mixing, then mechanical stirring, and finally ultrasonic treatment, the components of the encapsulating ink, particularly the two-dimensional nano-barrier filler, are fully and uniformly dispersed, effectively preventing filler agglomeration and sedimentation. This highly uniform and stable encapsulating ink ensures consistent ink rheological properties, high printing accuracy, and uniform, dense encapsulating film thickness when printed using a high-precision inkjet printing system. This significantly enhances the barrier properties of the encapsulating film, effectively preventing the penetration of external water and oxygen, thereby greatly improving the environmental stability and long-term reliability of perovskite quantum dot microarray devices and providing a more reliable basis for the repair of localized failures in the encapsulating film. (Example)

[0161] Preparation of perovskite quantum dot printing ink: CsPbBr3 quantum dots (emission peak ~518nm, photoluminescence quantum yield 75%) were dispersed in a mixed solvent of decane and chlorobenzene to form a printing ink with a concentration of 50mg / mL.

[0162] The printing equipment uses a 355nm ultraviolet nanosecond laser, and the donor consists of quartz glass / 50 nm Ti sacrificial layer / perovskite quantum dot ink layer. The acceptor substrate is a clean polyimide (PI) flexible film.

[0163] Perovskite quantum dot printing process: A 10×10 quantum dot array was printed using laser parameters of 30 μJ single-pulse energy and 20 μm dot spacing, with each dot having a diameter of approximately 5 μm. Fluorescence microscopy showed a uniform array, and the initial average fluorescence intensity was denoted as I0.

[0164] Example of ink material composition: The matrix resin is vinyl-terminated polydimethylsiloxane (PDMS) with a viscosity of 1000 cSt. The dynamic covalent crosslinking agent is furan-modified polyurethane oligomer (Fu-PU) and bismaleimide (BMI). The two-dimensional nano-barrier filler is an aminosilane-modified boron nitride nanosheet (BNNS) dispersion. The catalyst is a platinum catalyst.

[0165] The above components were mixed according to the proportions in Table 1, and after planetary stirring and ultrasonic treatment, three uniform encapsulation inks with a viscosity of 15 cP were obtained, which are suitable for inkjet printing. The three encapsulation inks correspond to Example 1, Example 2 and Example 3, respectively.

[0166] The encapsulation materials used in the comparative examples: Comparative Example 1 used commercially available UV-curable optical adhesive (NOA61) for encapsulation. Commercially available UV-curable optical adhesives have high transparency but lack self-healing capabilities. Comparative Example 2 used a pure PDMS encapsulation layer without dynamic crosslinking agents and BNNS. The pure PDMS encapsulation layer requires the addition of a catalyst in a standard ratio.

[0167] Table 1. Packaging Ink Formulation (Parts by Weight)

[0168] Preparation processes of Examples 1-3 and Comparative Examples 1 and 2: Examples 1-3 and Comparative Example 2 used a piezoelectric inkjet printing platform to print the encapsulation layer. The process was as follows: the prepared encapsulation ink was loaded into the ink cartridge, and the print head was precisely controlled so that the ink droplets covered each quantum dot and its surrounding area of ​​approximately 2 μm. After printing, the layer was preheated on an 80°C hot plate for 3 minutes, then treated at 120°C for 2 minutes, and finally cured under a 365 nm UV lamp for 40 seconds.

[0169] Comparative Example 1 uses spin coating to cover the entire substrate with NOA61 adhesive layer, and then directly irradiates it under a 365nm UV lamp for 60 seconds to cure.

[0170] The performance testing and data analysis included the following key tests to quantitatively evaluate the packaging effect: Mechanical stability test: The sample was fixed on a bending tester and subjected to continuous bending (radius of curvature r = 3 mm). The fluorescence intensity decay of a single micro-dot was monitored after a specific number of bends.

[0171] Self-healing performance test: The sample that has undergone 500 bends was placed on a 90℃ hot stage for 10 minutes and the fluorescence intensity recovery rate was measured after cooling.

[0172] Environmental stability test (accelerated aging test): The sample was placed in a constant temperature and humidity chamber at 85℃ and 85% relative humidity. The fluorescence intensity was measured periodically, and the time it took for the brightness to decay to 80% of the initial value was recorded, i.e., T was recorded. 80 .

[0173] Table 2 Summary of Packaging Performance Test Data

[0174] Comparing Example 1 and Comparative Example 2, it can be found that the dynamic covalent crosslinking agent (Fu-PU / BMI) is the source of the self-healing function. However, the content of the dynamic covalent crosslinking agent needs to be moderate. In Example 3, where the content of the dynamic covalent crosslinking agent is low, insufficient repair ability is observed.

[0175] Compared with Comparative Example 1 and Comparative Example 2, two-dimensional nano-barrier filler (BNNS) is the key to improving barrier properties. In Example 2, increasing the content of BNNS can further reduce water vapor transmission, but may slightly affect light transmittance.

[0176] Quantitative analysis of performance advantages: Taking Example 1 as an example, the retention rate after 500 bends is greater than 92%, T 80 With a recovery rate of over 97% after more than 240 hours, it is evident that it significantly outperforms traditional commercial optical adhesives and pure polymer encapsulation in the three key indicators of mechanical flexibility, active self-healing capability, and long-term environmental stability compared to Comparative Example 1.

[0177] In this application, the terms "embodiment" and "implementation" mean that a specific feature or characteristic described in connection with an embodiment can be included in at least one embodiment of this application. The appearance of these phrases in various places in the specification does not necessarily refer to the same embodiment, nor are they independent or alternative embodiments mutually exclusive with other embodiments. Those skilled in the art will understand, explicitly and implicitly, that the embodiments described in this application can be combined with other embodiments. Furthermore, it should be understood that the features, elements, or characteristics described in the various embodiments of this application can be arbitrarily combined to form another embodiment that does not depart from the spirit and scope of the technical solution of this application, provided there is no contradiction between them.

[0178] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application and are not intended to limit it. Although this application has been described in detail with reference to the above preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions to the technical solutions of this application should not depart from the spirit and scope of the technical solutions of this application.

Claims

1. A method for encapsulating perovskite quantum dot microarrays, characterized in that, include: We provide perovskite quantum dot microarrays and encapsulation inks; The encapsulation ink, by weight, is uniformly prepared from 80-120 parts of matrix resin, 5-20 parts of dynamic covalent crosslinking agent, 3-15 parts of two-dimensional nano barrier filler, 0.5 parts of catalyst, and solvent. The dynamic covalent crosslinking agent includes furan-terminated polyurethane oligomers and bismaleimide. The encapsulation ink is printed onto the perovskite quantum dot microarray and its periphery using a high-precision inkjet printing system. It is then heat-treated at 80°C for 5-10 minutes, followed by heat treatment at 120°C for 1-3 minutes. Finally, it is cured under 365nm ultraviolet light for 30-60 seconds until an encapsulation film is formed on the perovskite quantum dot microarray and its periphery. The matrix resin is a polydimethylsiloxane prepolymer, and the solvent is n-heptane; or, the matrix resin is an aqueous polyurethane dispersion, and the solvent is a mixture of deionized water and ethanol.

2. The perovskite quantum dot microarray encapsulation method according to claim 1, characterized in that, Before printing the encapsulating ink into the perovskite quantum dot microarray and its periphery using a high-precision inkjet printing system, the provision of the perovskite quantum dot microarray includes: coating the perovskite quantum dot microarray and its periphery with a long-chain hydrophobic ligand or an inorganic passivation layer.

3. The perovskite quantum dot microarray encapsulation method according to claim 1, characterized in that, The catalyst includes either boron trifluoride diethyl ether complex or trifluoromethanesulfonate.

4. The perovskite quantum dot microarray encapsulation method according to claim 1, characterized in that, The matrix resin is a polydimethylsiloxane prepolymer, the solvent is n-heptane, and the catalyst includes a platinum catalyst.

5. The perovskite quantum dot microarray packaging method according to claim 1, characterized in that, The encapsulation ink, calculated by mass parts, is prepared by mixing 100 parts of matrix resin, 20 parts of dynamic covalent crosslinking agent, 5 parts of two-dimensional nano barrier filler, and 0.5 parts of catalyst evenly and then adding solvent. The viscosity of the encapsulation ink is 10~20 cP.

6. The perovskite quantum dot microarray encapsulation method according to claim 5, characterized in that, The viscosity of the encapsulation ink is 15 cP.

7. The perovskite quantum dot microarray encapsulation method according to claim 1, characterized in that, The encapsulation ink also includes at least one of antioxidants, ultraviolet absorbers, and light stabilizers.

8. The perovskite quantum dot microarray encapsulation method according to claim 1, characterized in that, The perovskite quantum dot microarray is composed of any one of CsPbCl3, CsPbBr3, or a mixture of CsPbCl3 and CsPbBr3.

9. A method for repairing perovskite quantum dot microarray devices, characterized in that, A method for repairing perovskite quantum dot microarray devices prepared using the perovskite quantum dot microarray packaging method as described in any one of claims 1 to 8, the method comprising: providing the perovskite quantum dot microarray device; heating the perovskite quantum dot microarray device at 80 to 90°C for 5 to 10 minutes.

10. A method for preparing encapsulation ink, characterized in that, For implementing the perovskite quantum dot microarray encapsulation method as described in any one of claims 1 to 8, the encapsulation ink preparation method includes: mixing 80 to 120 parts of matrix resin, 5 to 20 parts of dynamic covalent crosslinking agent, 3 to 15 parts of two-dimensional nano barrier filler, 0.5 parts of catalyst, and solvent to obtain an intermediate mixture; stirring the intermediate mixture and then ultrasonically treating the intermediate mixture; to obtain the encapsulation ink.

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