High-stability perovskite quantum dot photosensitive resin based on DLP photoetching and preparation method and application thereof

Abstract

The invention discloses high-stability perovskite quantum dot photosensitive resin based on DLP photoetching and a preparation method and application thereof, and relates to the field of nanometer optoelectronic materials. The high-stability perovskite quantum dot photosensitive resin is prepared from the following components in percentage by mass: 1 to 8 percent of organosilane coated perovskite quantum dots, 1 to 5 percent of a photoinitiator and 87 to 94 percent of a polymer matrix, the polymer matrix can be subjected to a photopolymerization reaction; the perovskite quantum dot is a CsPbX3 perovskite quantum dot, wherein X is Cl or Br or I. The invention further discloses a preparation method of the perovskite quantum dot. The perovskite quantum dots are coated with organosilane, and a photopolymerization network formed by a polymer matrix is combined, so that dual protection is provided for the quantum dots, the quantum dots not only can be used in a daily living environment, but also can be applied to special environments such as high-humidity or underwater environments, and the application range of the perovskite quantum dots is greatly widened; the problem of poor environmental stability of perovskite quantum dots is effectively solved.

Description

Technical Field

[0001] The present invention relates to the field of nano-photoelectronic materials, and in particular to a high-stability perovskite quantum dot photosensitive resin based on DLP lithography, and a preparation method and application thereof. Background Art

[0002] Perovskite quantum dots (PQDs) have shown great potential for application in optoelectronics, particularly in Micro-LEDs, quantum dot light-emitting diodes (QLEDs), and high-resolution display technologies, due to their excellent photoluminescence properties, such as high quantum yield, narrow emission spectrum, and tunable band gap. However, PQDs face many challenges in practical applications.

[0003] Perovskite quantum dots (QDs) have extremely poor environmental stability and are extremely sensitive to moisture, oxygen, UV light, and heat. Exposure to air for just a few hours can lead to significant degradation, resulting in a sharp drop in luminescence intensity and a shift in the spectrum. Water molecules can disrupt their crystal structure, while oxygen molecules induce surface defects, accelerating non-radiative recombination. Traditional encapsulation methods, such as polymer coatings or inorganic oxide layers, can provide some protection, but often cause QD agglomeration or loss of optical performance due to interfacial compatibility issues.

[0004] Existing patterning technologies also have significant limitations. For example, the resolution of inkjet printing is limited by droplet diffusion and the "coffee ring effect," which occurs when material accumulates at the edges during solvent evaporation, resulting in uneven luminescence. This technology struggles to achieve sub-100-micron (<100μm) precision. Furthermore, capillary forces during solvent evaporation disrupt the dispersion of quantum dots, affecting pattern uniformity. While UV lithography can achieve micron-level high resolution, its process is highly complex, requiring mask alignment, multiple development steps, and etching. Organic solvents in photoresists (such as propylene glycol methyl ether acetate) and strong UV radiation can easily damage ligands on the quantum dot surface, leading to fluorescence quenching. Furthermore, photoresists have poor compatibility with quantum dots, easily inducing phase separation or agglomeration. Other technologies, such as nanoimprinting, are costly and have limited adaptability; electron beam lithography is inefficient and difficult to scale up.

[0005] In terms of multicolor integration, the emission color of perovskite quantum dots depends on the halogen composition (Cl / Br / I), but quantum dots of different compositions vary significantly in their sensitivity to the environment. For example, CsPbI3 is prone to phase transitions. Existing technologies make it difficult to precisely position and stabilize multicolor quantum dots on the same substrate, resulting in a narrow color gamut and poor color consistency in full-color displays.

[0006] From the perspective of large-scale production, traditional methods require a multi-step process, including quantum dot synthesis, separation, redispersion, and patterning. This process is very cumbersome and has a low yield rate. Moreover, quantum dots are susceptible to mechanical stress or chemical contamination during the transfer process, further reducing device performance.

[0007] In summary, current perovskite quantum dot patterning technology faces an irreconcilable contradiction between "stability, resolution, and process efficiency." High-resolution techniques (such as UV lithography) damage quantum dots, while gentler processes (such as inkjet printing) sacrifice resolution. Multi-color integration lacks compatible solutions, and large-scale production lacks an efficient, low-damage, one-step method. Therefore, there is an urgent need to develop a patterning technology that combines high stability, high resolution, multi-color compatibility, and process simplicity to promote the practical application of perovskite quantum dots in optoelectronic devices. Summary of the Invention

[0008] The purpose of the present invention is to overcome the shortcomings of the existing technology and provide a high-stability perovskite quantum dot based on DLP lithography and its preparation method and application. Through specific material ratios and process step design, the technical difficulties of perovskite quantum dots in environmental stability, resolution and multi-color integration are solved, while improving process efficiency and operability.

[0009] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0010] A high-stability perovskite quantum dot photosensitive resin based on DLP lithography comprises, by mass, 1-8% of organosilane-coated perovskite quantum dots, 1-5% of a photoinitiator, and 87-94% of a polymer matrix; the polymer matrix is ​​capable of undergoing a photopolymerization reaction; the perovskite quantum dots are CsPbX3 perovskite quantum dots, wherein X is Cl, Br, or I.

[0011] Furthermore, the organosilane includes at least one silane containing a hydrophobic group and at least one silane containing a polymerizable double bond; and the polymer matrix is ​​a mixture of benzyl methacrylate or methyl methacrylate and a crosslinking agent in a mass ratio of 1-2:1.

[0012] Furthermore, the crosslinking agent is tripropylene glycol diacrylate; the silane containing a hydrophobic group is diphenyldimethoxysilane; and the silane containing a polymerizable double bond is 3-(triethoxysilane)propyl methacrylate.

[0013] Furthermore, the photoinitiator is a mixture of one or more of bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butanone, and 2-hydroxy-2-methylpropiophenone.

[0014] The method for preparing the high-stability perovskite quantum dot photosensitive resin based on DLP lithography as described above comprises:

[0015] Step 1: Preparation of the precursor cesium oleate

[0016] Mix oleic acid, octadecene and CsCO3, heat to 115-125°C, evacuate, dry with magnetic stirring under nitrogen protection, and then heat to 140-160°C to react to obtain a clear cesium oleate solution;

[0017] Step 2: Preparation of organosilane-coated CsPbX3 perovskite quantum dots

[0018] When X in the CsPbX3 perovskite quantum dots is Br or I, the preparation method is as follows: mixing the original ligand octadecene and PbX2, heating to 115-125°C and evacuating the mixture, drying the mixture with magnetic stirring under nitrogen protection, adding organosilane and oleylamine until the solution is clear and free of precipitation, heating to 140-180°C, injecting a preheated cesium oleate solution, reacting for 4.5-5.5 seconds, cooling the mixture to room temperature in an ice-water bath, and introducing air and stirring to hydrolyze the silane to form an organosilica matrix;

[0019] When X in CsPbX3 perovskite quantum dots is Cl, a mixture of octadecene, tri-n-octylphosphine oxide and PbX2 is used as the original ligand, and the preparation method is the same as when X is Br or I;

[0020] Step 3: Purification

[0021] The organosilane-coated perovskite quantum dots prepared in step S2 were pipetted into a centrifuge tube, centrifuged for 10 minutes, and then the precipitate was washed with n-hexane. This operation was repeated, and the solid precipitate was vacuum dried.

[0022] Step 4: Preparation of high-stability perovskite quantum dot photosensitive resin

[0023] In a light-proof environment, the polymer matrix and the crosslinking agent are mixed in proportion, and the photoinitiator and the organosilane-coated perovskite quantum dots are added in proportion to obtain a mixture, and the mixture is ultrasonically dissolved at 35-40° C. to obtain the finished product.

[0024] Furthermore, in step 1, 2.5 mL of oleic acid, 30 mL of octadecene and 0.8 g of CsCO3 were mixed, heated to 115-125°C and vacuumed for 10 min, dried with magnetic stirring under nitrogen protection for 1 h, and then heated to 140-160°C for reaction for 2 h.

[0025] Furthermore, in step 2, when X in the CsPbX3 perovskite quantum dots is Br or I, the original ligand is 10 mL of octadecene and 0.138 g of PbX2; when X in the CsPbX3 perovskite quantum dots is Cl, the original ligand is 10 mL of octadecene, 1 mL of tri-n-octylphosphine oxide and 0.104 g of PbCl2; the amount of organosilane added is 1-3 mL, the amount of oleylamine added is 0.5 mL, and the amount of preheated cesium oleate solution injected is 1 mL; in step 4, the time for ultrasonic dissolution does not exceed 30 min.

[0026] The present invention also provides the use of the high-stability perovskite quantum dot photosensitive resin in patterning using a DLP 3D printer.

[0027] Furthermore, the specific method of patterning using a DLP 3D printer is as follows:

[0028] S1, design the pattern and import it into the DLP 3D printer;

[0029] S2, placing a glass slide in the reaction tank of the DLP 3D printer;

[0030] S3, aspirate high-stability perovskite quantum dot photosensitive resin onto a glass slide and cover it with a fluorinated glass slide;

[0031] S4, select the target pattern on the DLP 3D printer, set the exposure time for printing, and the printing time should not exceed 100 seconds;

[0032] S5, after printing is completed, the slides are separated, the pattern is cleaned with anhydrous ethanol, and air-dried to obtain the final sample.

[0033] Furthermore, in step S4, during the printing process, the exposure wavelength of the DLP lithography is 380-420 nm, and the light intensity is 5-50 mW / cm 2 , the exposure time for a single layer is 20-100 seconds.

[0034] Compared with the prior art, the present invention has the following beneficial effects:

[0035] (1) Traditional perovskite quantum dots are extremely sensitive to moisture, oxygen, ultraviolet light, and heat. They will degrade after short exposure to air, resulting in decreased luminescence intensity and spectral shift. The present invention provides dual protection for quantum dots by coating perovskite quantum dots with organosilane and combining them with a photopolymerization network formed by a polymer matrix. After 180 days in a dry, light-proof environment at room temperature, the luminescence intensity decreases by less than 6%, and after immersion in deionized water for 30 days, it still maintains a luminescence intensity of more than 88.4%. This makes quantum dots not only usable in daily life environments, but also in special environments such as high humidity or underwater. This greatly broadens the application range of perovskite quantum dots and effectively solves the problem of poor environmental stability of perovskite quantum dots.

[0036] (2) The present invention utilizes DLP 3D printing technology to achieve high-precision patterning of perovskite quantum dots. During the printing process, by precisely controlling the exposure time, the construction of precise quantum dot patterns and arrays is completed in a single step. The printed patterns are highly accurate, with clear boundaries and uniform fluorescence distribution. Accuracy of sub-hundred microns or even higher can be achieved, meeting the demand for high-resolution patterns in fields such as optoelectronic devices.

[0037] (3) The present invention has advantages in multi-color integration. Through specific material ratios and processes, it is possible to prepare high-stability perovskite quantum dot photosensitive resins with different halogen components (such as CsPbCl3, CsPbBr3, and CsPbI3), and achieve patterning using DLP 3D printing technology. Quantum dots of different colors can maintain good stability and luminescence performance in the polymer network, making it possible to realize full-color display devices, and is expected to solve the problems of narrow color gamut and poor color consistency of existing full-color display devices.

[0038] (4) The present invention can prepare a highly stable perovskite quantum dot photosensitive resin using a simple method. The DLP 3D printing process is also relatively simple. Simply import the designed pattern into the printer and set the exposure time to complete the printing. This simple process reduces production costs and difficulty, improves production efficiency, is more suitable for large-scale production, and can promote the practical application of perovskite quantum dots in optoelectronic devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 The fluorescence emission spectra of organosilane-coated perovskite quantum dots in Examples 1, 2, and 3 of the present invention are shown;

[0040] Figure 2 XRD patterns of organosilane-coated CsPbBr3 perovskite quantum dots in Example 1 of the present invention and non-silane-coated CsPbBr3 perovskite quantum dots in Comparative Example 1;

[0041] Figure 3 Schematic diagram of the photopolymerization process in Example 1 of the present invention;

[0042] Figure 4 Schematic diagram of the DLP 3D printing process in Example 1 of the present invention;

[0043] Figure 5 The giant panda pattern printed in Example 1 of the present invention;

[0044] Figure 6 The perovskite quantum dot array pattern in Examples 1, 2, and 3 of the present invention;

[0045] Figure 7This is a comparison chart of the quantum yields of CsPbBr3 perovskite quantum dots before and after polymerization in Example 4 of the present invention;

[0046] Figure 8 Schematic diagram of the change in fluorescence intensity of CsPbBr3 perovskite quantum dots after polymerization at room temperature (dry and dark) in Example 4 of the present invention;

[0047] Figure 9 Schematic diagram of the change in fluorescence intensity of CsPbBr3 perovskite quantum dots immersed in deionized water after polymerization in Example 4 of the present invention. DETAILED DESCRIPTION

[0048] The present invention will be further described below with reference to the accompanying drawings and examples. The embodiments of the present invention include but are not limited to the following examples.

[0049] The present invention provides a high-stability perovskite quantum dot photosensitive resin based on DLP lithography, which is composed of a polymer matrix, an organosilane, a photoinitiator, and perovskite quantum dots. The perovskite quantum dots are specifically CsPbX3 perovskite quantum dots (X=Cl, Br, or I). CsPbX3 quantum dots are expected to become the core material of the next generation of optoelectronic devices due to their high luminous efficiency, spectral tunability, and low-cost preparation advantages. The organosilane includes at least one silane containing a hydrophobic group and at least one silane containing a polymerizable double bond. Preferably, the silane containing a hydrophobic group is diphenyldimethoxysilane, and the silane containing a polymerizable double bond is 3-(triethoxysilyl)propyl methacrylate. The polymer matrix is ​​a mixture of benzyl methacrylate (BZMA) or methyl methacrylate (MMA) and a crosslinker (TPGDA, crosslinker). Preferably, the crosslinker is tripropylene glycol diacrylate (TPGDA). The photoinitiator is selected from one or more of bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide (BAPO), 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butanone (Irgacure369), and 2-hydroxy-2-methylpropiophenone (1173).

[0050] Specific examples are given below.

[0051] Example 1

[0052] The perovskite quantum dots in the high-stability perovskite quantum dot photosensitive resin provided in this embodiment are CsPbBr3 perovskite quantum dots, and the specific preparation method is as follows:

[0053] S1, preparation of organosilane-coated CsPbBr3 perovskite quantum dots:

[0054] (1) Preparation of cesium oleate solution: 2.5 mL of oleic acid (OA), 30 mL of octadecene (ODE), and 0.8 g of CsCO3 were added to a 100 mL three-necked flask in sequence. The temperature was raised to 120°C, and a vacuum was applied for 10 minutes. Then, nitrogen was introduced and the mixture was dried under magnetic stirring for 1 hour under nitrogen protection. The temperature was then raised to 150°C and the reaction was continued for 2 hours to obtain a cesium oleate solution.

[0055] (2) Preparation of organosilane-coated quantum dots: 10 mL of octadecene (ODE) and 0.138 g of PbBr2 were added to another 100 mL three-necked flask in sequence. The temperature was raised to 120°C, vacuumed for 10 min, and nitrogen was introduced. The mixture was magnetically stirred and dried for 1 h under nitrogen protection. 0.5 mL of diphenyldimethoxysilane (DMDPS), 0.5 mL of 3-(triethoxysilyl)propyl methacrylate (TESPMA), and 0.5 mL of oleylamine (OAM) were added to the flask and stirred until the solution was clear and free of precipitation. The temperature was then raised to 150°C. 1 mL of preheated cesium oleate solution (100°C) was then injected. After reacting for 5 s, the mixture was rapidly cooled to room temperature in an ice-water bath until no new solid was produced. The flask was placed in an air environment (25° C., 40% humidity) and stirred for 4 hours to allow the silane to hydrolyze and form an organic silica matrix through silanization. The addition of the organic silane served to coat the quantum dots and improve the stability of the quantum dots.

[0056] (3) Purification of quantum dots: Use a pipette to draw the solution from the flask into a centrifuge tube. Then, add a small amount of n-hexane to the flask to clean it, and combine the washing liquid into the centrifuge tube. After centrifugation at 8000 rpm for 10 minutes, wash the precipitate with n-hexane. Repeat this operation twice, pour out the liquid in the centrifuge tube, place the precipitate in a vacuum drying oven, and dry it at 60°C under vacuum for 24 hours to obtain organosilane-coated CsPbBr3 perovskite quantum dot powder. This process removes impurities in the reaction and ensures the purity of the quantum dots.

[0057] The fluorescence emission spectrum of the organosilane-coated CsPbBr3 perovskite quantum dots prepared in this example is shown in FIG. Figure 1 As shown (middle curve), the XRD pattern of organosilane-coated CsPbBr3 perovskite quantum dots is as follows Figure 2 shown (upper curve).

[0058] S2, preparation of organosilane-coated CsPbBr3 perovskite quantum dot photosensitive resin:

[0059] In a brown light-proof glass bottle, 5.52 g of benzyl methacrylate (BZMA) and 3.68 g of tripropylene glycol diacrylate (TPGDA) were added in sequence, followed by 0.2 g of bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide (BAPO) and 0.6 g of the organosilane-coated CsPbBr3 perovskite quantum dot powder prepared in step S1. The glass bottle was then transferred to an ultrasonic cleaner for ultrasonic dissolution (10 min, 35 ° C). Finally, the brown glass bottle was placed in a refrigerator for storage to obtain a finished photosensitive resin product.

[0060] The photosensitive resin prepared above is applied to a DLP 3D printer to achieve quantum dot patterning. The specific method is as follows:

[0061] Place a glass slide with a size of 5cm×2cm in the reaction tank of the DLP 3D printer to ensure that it is placed stably. Use a pipette to draw 0.5mL of photosensitive resin from a brown glass bottle and add it dropwise on the surface of the glass slide to ensure that the liquid is evenly covered. Subsequently, take another glass slide and gently cover it on the reaction liquid, ensuring that the two glass slides are in close contact to ensure that the reaction liquid is evenly distributed on the glass slide. Select a suitable pattern for printing on the printer, and the printing time is usually no more than 100 seconds. The pattern selected in this embodiment is a giant panda and an array diagram. After printing is completed, the glass slide printed with the pattern is cleaned with anhydrous ethanol to wash off the excess reaction liquid. Finally, use an air dryer to air dry the sample until the printed sample is completely dry to obtain the final printed sample.

[0062] During the DLP 3D printing process, photopolymerization occurs. Figure 3 This is a schematic diagram of the photopolymerization process. Under 405nm blue-violet light irradiation, the photoinitiator absorbs light energy and generates free radicals, initiating the polymerization reaction of the methacrylate group. During the polymerization process, the silane-coated quantum dots are evenly distributed in the cross-linked polymer network. After polymerization, the quantum dot array emits uniform fluorescence under 365nm excitation, ensuring the stability and luminescence performance of the quantum dots in the polymer matrix.

[0063] Figure 4The complete process of perovskite quantum dot patterning using DLP technology is demonstrated. First, the pattern and structure are designed according to the requirements in the PC design interface, and these design files are converted into a digital format suitable for the DLP printer through computer software. Then, the digital micromirror device (DMD) in the DLP device accurately projects the computer-generated pattern onto the photosensitive resin of the printing platform. When the resin is exposed to ultraviolet light (405nm wavelength), the photosensitive material in the resin rapidly undergoes polymerization to form a high-resolution pattern structure. The polymerization reaction completes the construction of precise quantum dot patterns and arrays in one step through precise control of the exposure time. In this way, DLP technology can achieve high-precision patterning of perovskite quantum dots and provides important technical support for the application of quantum dots in optoelectronic devices and other fields.

[0064] Figure 5 This is a green giant panda pattern printed using DLP lithography technology. The pattern has clear boundaries and evenly distributed fluorescence. Figure 6 (b) shows an image of a perovskite quantum dot microarray printed in this example. Each dot has a consistent diameter, uniform spacing, and orderly arrangement, demonstrating the high precision of the printing system. Furthermore, the luminous intensity across the array is uniform, with brightness differences of less than 3% between color arrays, demonstrating the optical stability of the printing system in this example.

[0065] Comparative Example 1

[0066] The perovskite quantum dots of this embodiment are CsPbBr3 perovskite quantum dots that are not coated with organosilane. The specific preparation method is as follows:

[0067] (1) Preparation of cesium oleate: the same as step S1 (1) in Example 1.

[0068] (2) Quantum dot synthesis: 10 mL of octadecene (ODE) and 0.138 g of PbBr2 were added to a 100 mL three-necked flask, the temperature was raised to 120°C, and the mixture was evacuated for 10 min, and nitrogen was introduced. The mixture was magnetically stirred and dried under nitrogen protection for 1 h. 0.5 mL of oleylamine (OAM) was added to the flask and stirred until the solution was clear and free of precipitates. The temperature was then raised to 150°C. 1 mL of preheated cesium oleate solution (100°C) was then injected. After reacting for 5 s, the mixture was rapidly cooled to room temperature in an ice-water bath until no new solid was produced.

[0069] (3) Purification of quantum dots: the same as step S1 (3) in Example 1.

[0070] The XRD pattern of the CsPbBr3 perovskite quantum dots prepared in this example is as follows Figure 2As shown (lower curve). As can be seen from the figure, the diffraction peak position of CsPbBr3 remains unchanged after being coated with organosilane, indicating that the modification of silane has no effect on the crystal structure of quantum dots, and a bun peak appears near 2θ = 20°, which can be attributed to the obtained amorphous SiO2 network.

[0071] Example 2

[0072] The perovskite quantum dots in the high-stability perovskite quantum dot photosensitive resin provided in this embodiment are CsPbCl3 perovskite quantum dots. The method for preparing the high-stability perovskite quantum dot photosensitive resin is similar to that in Example 1, but differs from Example 1 in that:

[0073] Preparation of organosilane-coated quantum dots: To a 100mL three-necked flask, 10mL of octadecene (ODE), 1mL of tri-n-octylphosphine oxide (TOP), and 0.104g of PbCl2 were added in sequence. The temperature was raised to 120°C, vacuumed for 10 minutes, and dried under magnetic stirring for 1 hour under nitrogen protection. 0.5mL of diphenyldimethoxysilane (DMDPS), 0.5mL of 3-(triethoxysilyl)propyl methacrylate (TESPMA), and 0.5mL of oleylamine (OAM) were added to the flask and stirred until the solution was clear and free of precipitate. The temperature was then raised to 180°C. 1mL of preheated cesium oleate solution (100°C) was then injected. After reacting for 5 seconds, the mixture was rapidly cooled to room temperature in an ice-water bath until no new solid was produced. Subsequent steps were the same as in Example 1.

[0074] The fluorescence emission spectrum of the organosilane-coated CsPbCl3 perovskite quantum dots prepared in this example is shown in FIG. Figure 1 shown (left curve).

[0075] The method for realizing quantum dot patterning in this embodiment is the same as that in embodiment 1. Figure 6 a is a diagram of the perovskite quantum dot microarray printed in this embodiment. The diameter of each dot is consistent, the spacing is uniform, and the arrangement is orderly, demonstrating the high precision of the printing system; the luminous intensity in the array is uniform, and the brightness difference between the color arrays is less than 3%, reflecting the optical stability of the printing system.

[0076] Example 3

[0077] The perovskite quantum dots in the high-stability perovskite quantum dot photosensitive resin provided in this embodiment are CsPbI3 perovskite quantum dots. The method for preparing the high-stability perovskite quantum dot photosensitive resin refers to Example 1, and during the preparation process, PbBr2 in Example 1 is replaced with PbI2.

[0078] The fluorescence emission spectrum of the organosilane-coated CsPbI3 perovskite quantum dots prepared in this example is shown in FIG. Figure 1 shown (right curve).

[0079] The method for realizing quantum dot patterning in this embodiment is the same as that in embodiment 1. Figure 6 c is a diagram of the perovskite quantum dot microarray printed in this embodiment. The diameter of each dot is consistent, the spacing is uniform, and the arrangement is orderly, demonstrating the high precision of the printing system; the luminous intensity in the array is uniform, and the brightness difference between the color arrays is less than 3%, reflecting the optical stability of the printing system.

[0080] Example 4

[0081] This example uses CsPbBr3 perovskite quantum dots as an example to explore the protective effects of organosilane and polymer matrices on quantum dots. The synthesis of the perovskite quantum dots and the preparation of the quantum dot photosensitive resin in this example refer to Example 1. Using photopolymerization, a 5 cm diameter and 2 cm high plastic sheet containing CsPbBr3 quantum dots was prepared, emitting green fluorescence. Figure 7 This is a comparison of the quantum yield of perovskite quantum dots (CsPbBr3) before and after polymerization in this embodiment. Figure 7 The inset shows the transition from solution to solid state, indicating that the photopolymerization process has been successfully completed and the quantum dots are still uniformly distributed after curing; Figure 7 The fluorescence emission spectra and PLQY before and after polymerization are also shown. The peak intensity of fluorescence emission after polymerization is 98% of that before polymerization. Although the PLQY of quantum dots after polymerization (84.8%) is lower than that of unpolymerized quantum dots (87.3%), it still maintains efficient luminescence performance, indicating that the polymer matrix has little effect on the optical properties of quantum dots.

[0082] Schematic diagram of the fluorescence intensity change of CsPbBr3 perovskite quantum dots after polymerization at room temperature (dry and away from light) Figure 8 As shown in the figure, the PL intensity changes of CsPbBr3 perovskite quantum dot plastic during long-term storage (in a dry, light-shielded environment). The sample was kept in a dry, light-shielded environment at room temperature, and the luminescence intensity was measured regularly under 365nm excitation. The luminescence intensity of the sample decreased by less than 6% after 180 days, indicating that the silane modification and polymer network provide excellent environmental stability for the quantum dots.

[0083] Schematic diagram of the fluorescence intensity change of CsPbBr3 perovskite quantum dots after polymerization and immersion in deionized water. Figure 9 The figure shows the change in luminescence intensity of CsPbBr3 perovskite quantum dot plastic immersed in deionized water (shielded from light). The sample was immersed in deionized water to simulate a high-humidity environment, and the luminescence intensity was tested regularly. After 30 days of storage in water, the sample still retained over 88.4% of its luminescence intensity, indicating that the silane modification layer significantly improved the water resistance of the quantum dots.

[0084] These test results confirm the dual protective effects of silane modification and polymer network, enabling the use of quantum dots in daily life environments and also in high humidity or underwater applications.

[0085] The above embodiment is only one of the preferred implementation methods of the present invention and should not be used to limit the scope of protection of the present invention. Any changes or modifications that have no substantive meaning made to the main design concept and spirit of the present invention, as long as the technical problems solved are still consistent with the present invention, should be included in the scope of protection of the present invention.

Claims

1. A high-stability perovskite quantum dot photosensitive resin based on DLP lithography, characterized in that: The invention comprises, by mass, 1-8% of organosilane-coated perovskite quantum dots, 1-5% of a photoinitiator and 87-94% of a polymer matrix; the polymer matrix can undergo a photopolymerization reaction; the perovskite quantum dots are CsPbX3 perovskite quantum dots, wherein X is Cl, Br or I.

2. The high-stability perovskite quantum dot photosensitive resin based on DLP lithography according to claim 1, characterized in that: The organic silane comprises at least one silane containing a hydrophobic group and at least one silane containing a polymerizable double bond; and the polymer matrix is ​​a mixture of benzyl methacrylate or methyl methacrylate and a crosslinking agent in a mass ratio of 1-2:

1.

3. The high-stability perovskite quantum dot photosensitive resin based on DLP lithography according to claim 2, characterized in that: The crosslinking agent is tripropylene glycol diacrylate; the silane containing a hydrophobic group is diphenyldimethoxysilane; and the silane containing a polymerizable double bond is 3-(triethoxysilane)propyl methacrylate.

4. The high-stability perovskite quantum dot photosensitive resin based on DLP lithography according to claim 3, characterized in that: The photoinitiator is a mixture of one or more of bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butanone, and 2-hydroxy-2-methylpropiophenone.

5. The method for preparing a high-stability perovskite quantum dot photosensitive resin based on DLP lithography according to claim 4, wherein: include: Step 1: Preparation of the precursor cesium oleate Mix oleic acid, octadecene and CsCO3, heat to 115-125°C, evacuate, dry with magnetic stirring under nitrogen protection, and then heat to 140-160°C to react to obtain a clear cesium oleate solution; Step 2: Preparation of organosilane-coated CsPbX3 perovskite quantum dots When X in the CsPbX3 perovskite quantum dots is Br or I, the preparation method is as follows: mixing the original ligand octadecene and PbX2, heating to 115-125°C and evacuating the mixture, drying the mixture with magnetic stirring under nitrogen protection, adding organosilane and oleylamine until the solution is clear and free of precipitation, heating to 140-180°C, injecting a preheated cesium oleate solution, reacting for 4.5-5.5 seconds, cooling the mixture to room temperature in an ice-water bath, and introducing air and stirring to hydrolyze the silane to form an organosilica matrix; When X in CsPbX3 perovskite quantum dots is Cl, a mixture of octadecene, tri-n-octylphosphine oxide and PbX2 is used as the original ligand, and the preparation method is the same as when X is Br or I; Step 3: Purification The organosilane-coated perovskite quantum dots prepared in step S2 were pipetted into a centrifuge tube, centrifuged for 10 minutes, and then the precipitate was washed with n-hexane. This operation was repeated, and the solid precipitate was vacuum dried. Step 4: Preparation of high-stability perovskite quantum dot photosensitive resin In a light-proof environment, the polymer matrix and the crosslinking agent are mixed in proportion, and the photoinitiator and the organosilane-coated perovskite quantum dots are added in proportion to obtain a mixture, and the mixture is ultrasonically dissolved at 35-40° C. to obtain the finished product.

6. The method for preparing a high-stability perovskite quantum dot photosensitive resin based on DLP lithography according to claim 5, characterized in that: In step 1, 2.5 mL of oleic acid, 30 mL of octadecene and 0.8 g of CsCO3 were mixed, heated to 115-125°C and vacuumed for 10 min, dried under magnetic stirring under nitrogen protection for 1 h, and then heated to 140-160°C for reaction for 2 h.

7. The method for preparing a high-stability perovskite quantum dot photosensitive resin based on DLP lithography according to claim 6, characterized in that: In step 2, when X in the CsPbX3 perovskite quantum dots is Br or I, the original ligand is 10mL of octadecene and 0.138g of PbX2; when X in the CsPbX3 perovskite quantum dots is Cl, the original ligand is 10mL of octadecene, 1mL of tri-n-octylphosphine oxide and 0.104g of PbCl2; the amount of organosilane added is 1-3mL, the amount of oleylamine added is 0.5mL, and the amount of preheated cesium oleate solution injected is 1mL; in step 4, the ultrasonic dissolution time does not exceed 30min.

8. Use of the high-stability perovskite quantum dot photosensitive resin according to any one of claims 1 to 4 in patterning using a DLP 3D printer.

9. The use according to claim 8, characterized in that The specific method of patterning using a DLP 3D printer is as follows: S1, design the pattern and import it into the DLP 3D printer; S2, placing a glass slide in the reaction tank of the DLP 3D printer; S3, aspirate high-stability perovskite quantum dot photosensitive resin onto a glass slide and cover it with a fluorinated glass slide; S4, select the target pattern on the DLP 3D printer, set the exposure time for printing, and the printing time should not exceed 100 seconds; S5, after printing is completed, the slides are separated, the pattern is cleaned with anhydrous ethanol, and air-dried to obtain the final sample.

10. The use according to claim 9, characterized in that In step S4, during the printing process, the exposure wavelength of the DLP lithography is 380-420 nm, and the light intensity is 5-50 mW / cm 2 , the exposure time for a single layer is 20-100 seconds.

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