Perovskite nanocrystal array and manufacturing method and application thereof

Abstract

The invention discloses a perovskite nanocrystal array and a manufacturing method and application thereof, and belongs to the technical field of nano functional materials. The perovskite nanocrystal array provided by the invention is provided with the cross-linked polymer nanorod array; a plurality of perovskite nanocrystals are armored in each cross-linkable polymer nanorod; the perovskite nanocrystal is formed by carrying out swelling-deswelling induced in-situ crystallization on a perovskite precursor. According to the method, the cross-linked polymer nano-column arrays are arranged, and the perovskite nano-crystals are armored in each cross-linked polymer nano-column array in situ through a swelling-deswelling mechanism, so that large-scale manufacturing of the perovskite nano-crystal array with nanoscale precision can be effectively achieved; and the formed perovskite nanocrystal can be endowed with excellent environmental stability and surface optical performance, so that the perovskite nanocrystal array has high-quality metasurface optical performance.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of nanofunctional materials, and particularly relates to a perovskite nanocrystal array and a manufacturing method and application thereof. BACKGROUND

[0002] In order to meet the development needs of miniaturized integrated optoelectronic devices, the manufacturing of perovskite nanocrystal arrays has become one of the research hotspots of lead halide perovskite nanocrystals. However, perovskite nanocrystals are generally subject to lattice instability and reduced luminescence in air, which greatly hinders the construction of large-area perovskite nanocrystal arrays. Therefore, the large-scale construction of perovskite nanocrystal arrays has great market value.

[0003] At present, the construction strategies of perovskite nanocrystal arrays are generally divided into "top-down" and "bottom-up" two routes. Among them, the "top-down" construction strategy such as electron beam lithography (EBL), focused ion beam lithography (FIB) and ultraviolet lithography (UVL) can achieve high-precision construction of perovskite arrays, but the equipment relied on by this route is expensive and the process is time-consuming, which restricts the manufacturing of large-area perovskite micro-nano arrays; the "bottom-up" construction strategy such as substrate pre-array, inkjet printing and 3D printing can achieve low-cost manufacturing of large-area perovskite micro-nano arrays, but it relies on a molecular-level self-assembly process, which not only limits the resolution and pixel size of the perovskite nanocrystal array to the micron level, but also easily causes the non-uniformity of the array structure, reducing the performance of perovskite devices.

[0004] Therefore, the miniaturization of perovskite pixels and the optimization of the resolution and stability of perovskite nanocrystal arrays are still challenging, and it is necessary to develop an efficient construction method for large-area perovskite nanocrystal patterns with ultra-high resolution and excellent stability. SUMMARY

[0005] The application discloses a perovskite nanocrystal array and a manufacturing method and application thereof, which effectively achieves the construction of a perovskite nanocrystal array with a nanoscale resolution and a centimeter-level area by setting a combination technology of nano-imprint soft lithography combined with swelling-deswelling induced in-situ crystallization.

[0006] In order to achieve the above-mentioned purpose, the application provides the following technical scheme:

[0007] The first aspect of the application provides a perovskite nanocrystal array, which has a cross-linked polymer nanocolumn array arranged therein;

[0008] Each of the cross-linked polymer nanocolumns is armored with a plurality of perovskite nanocrystals;

[0009] The perovskite nanocrystals are formed by swelling-deswelling induced in-situ crystallization of perovskite precursors.

[0010] According to the first aspect of the present disclosure, the cross-linking polymer further co-polymerizes a perovskite passivation monomer.

[0011] According to the first aspect of the present disclosure, the perovskite passivation monomer is selected from at least one of 4-vinylpyridine, acrylic acid, dimethylaminoethyl methacrylate, 2-(methylthio)ethyl methacrylate, 2-methacryloyloxyethylphosphocholine, or carboxybetaine methacrylate.

[0012] According to the first aspect of the present disclosure, the cross-linking polymer comprises a thermal cross-linking polymer and a photo cross-linking polymer;

[0013] and / or, the thermal cross-linking polymer comprises poly(styrene-r-glycidyl methacrylate);

[0014] and / or, the photo cross-linking polymer comprises poly(styrene-r-(4-acryloyloxybenzophenone)).

[0015] According to the first aspect of the present disclosure, the cross-linking polymer nanocolumn array has the following geometric characteristics:

[0016] (1) the period is 350-600 nm;

[0017] (2) the height is 350-400 nm;

[0018] (3) the area is 1-64 mm 2 .

[0019] The second aspect of the present application further provides a method for manufacturing a perovskite nanocrystal array, which comprises the following steps:

[0020] providing a nanopore array soft template;

[0021] after loading the nanopore array soft template with a cross-linking polymer precursor solution, the nanopore array soft template is used for imprinting a hydrophilic perovskite substrate, and after the imprinting is completed, solvent evaporation and demolding treatment are sequentially performed, so that a cross-linking polymer nanocolumn array precursor is formed on the hydrophilic perovskite substrate;

[0022] after etching treatment of the cross-linking polymer nanocolumn array precursor, cross-linking of the cross-linking polymer lattice is initiated, and a cross-linking polymer nanocolumn array is obtained;

[0023] after sequentially immersing the cross-linking polymer nanocolumn array in a lead bromide DMF solution for swelling, and immersing in a cesium bromide methanol solution for deswelling and inducing in-situ crystallization, annealing and drying are performed, and the perovskite nanocrystal array is obtained.

[0024] According to the second aspect of the present disclosure, the etching treatment comprises oxygen plasma etching or reactive ion beam etching.

[0025] The etching parameters of the oxygen plasma etching are: the pressure in the cavity is 60 Pa, the radio frequency source power is 20 W, and the processing time is 240-420 s.

[0026] The etching parameters of the reactive ion beam etching are: the oxygen flow rate is 35 s.c.c.m., the pressure is 60 Pa, the power is 60 W, and the processing time is 20-40 s.

[0027] According to the second aspect of the present disclosure, the preparation method of the nanopore array soft template comprises:

[0028] etching a silicon nanopillar array template;

[0029] After injecting SYLGARD 184-PDMS into the silicon nanopillar array template and removing the bubbles, sequentially performing solidification and demolding, a nanopore array soft template is obtained.

[0030] The array pattern of the nanopore array soft template is complementary to that of the silicon nanopillar array template.

[0031] According to the second aspect of the present disclosure, the molar concentration of the lead bromide DMF solution is 0.5-1 mol / L, and the concentration of the cesium bromide methanol solution is 10-15 mg / mL.

[0032] The third aspect of the present application further provides an application of the perovskite nanocrystal array of the present application to the manufacture of a perovskite light-emitting device.

[0033] Compared with the prior art, the advantages or beneficial effects of the embodiments of the present application at least include:

[0034] The perovskite nanocrystal array provided by the first aspect of the present application can achieve the regulation of the pixel size of the perovskite nanocrystal array by adjusting the lattice parameters and pixel size of the cross-linked polymer nanopillar array, effectively achieving the large-scale manufacturing of the nanoscale precision perovskite nanocrystal array; secondly, the cross-linked polymer nanopillar armor structure can protect the perovskite nanocrystal, not only giving the perovskite nanocrystal excellent environmental stability, but also achieving the optimization of the surface optical performance of the perovskite nanocrystal array, giving the perovskite nanocrystal array high-quality metasurface optical performance, such as surface lattice resonance with a quality factor of 121, strong coupling Rabi splitting phenomenon, etc.

[0035] The manufacturing method provided in the second aspect of the present application constructs a cross-linked polymer nanocolumn array on a hydrophilic perovskite substrate through nanoimprint soft lithography technology, and in-situ armors perovskite nanocrystals in the cross-linked polymer nanocolumn through swelling-deswelling, so that the high-efficiency manufacturing of a perovskite nanocrystal array with nanoscale resolution and centimeter-scale area is achieved. Specifically, the nanoimprint soft lithography technology is used to create a cross-linked polymer nanocolumn array on a hydrophilic perovskite substrate, which not only effectively achieves the accurate regulation of the lattice parameters and pixel size of the perovskite nanocrystal array, but also can achieve the repeated construction of the perovskite nanocrystal array through the nanoimprint of the nanocolumn array soft template. At the same time, the swelling-deswelling is used to in-situ generate perovskite nanocrystals in the cross-linked polymer nanocolumn and form an armored structure, which effectively avoids the direct damage of the high-energy beam in the etching process of the perovskite micro-nano array construction. Therefore, the perovskite nanocrystal array can not only have excellent photoelectric performance, but also can achieve the large-scale construction of the perovskite nanocrystal array with nanoscale resolution and centimeter-scale area. BRIEF DESCRIPTION OF DRAWINGS

[0036] In order to more clearly illustrate the technical solutions of the present application, the drawings needed in the following embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments described in the present application, and other drawings can also be obtained according to these drawings without creative labor for those skilled in the art.

[0037] Figure 1 The structural schematic diagram of the perovskite nanocrystal array provided in the present application is shown in the figure.

[0038] Figure 2 The laser confocal microscope image of the perovskite nanocrystal array manufactured in Example 1 of the present application is shown in the figure.

[0039] Figure 3 The structural color optical photo and the optical photo under ultraviolet excitation of the perovskite nanocrystal array manufactured in Example 1 of the present application are shown in the figure.

[0040] Figure 4 The optical photo of the flexible perovskite nanocrystal array manufactured in Example 2 of the present application is shown in the figure.

[0041] Figure 5 The particle size distribution of the polymer nanocolumn of the perovskite nanocrystal array obtained by different oxygen plasma etching time and the change curve of the average particle size with the oxygen plasma etching treatment time provided in the present application are shown in the figure.

[0042] Figure 6 The water contact angle test result figure provided in the present application is shown in the figure.

[0043] Figure 7 The water stability test result figure provided in the present application is shown in the figure.

[0044] Figure 8 Figures of the luminescence performance test results of the perovskite nanocrystal arrays manufactured in Example 5 and Example 6 provided in the present application;

[0045] Figure 9 Figures of the SEM and super surface optical property characterization results of the perovskite nanocrystal arrays with different periods provided in the present application. DETAILED DESCRIPTION

[0046] The technical solutions of the present application will be described clearly and completely below in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making creative efforts fall within the scope of protection of the present application.

[0047] In the related description of the present application, the term “and / or” is used to describe the association relationship of the associated objects, which means that there can be three kinds of relationships, for example, A and / or B, which can mean that A exists alone, B exists alone and A and B exist simultaneously. Wherein A and B can be singular or plural.

[0048] In the related description of the present application, the term “at least one” means one or more, wherein “multiple” means two or more than two. “At least one” or similar description means any combination of the items, including any combination of single item or multiple items. For example, “at least one of A, B or C”, or “at least one of A, B and C”, means one of A, B, C, A+B, A+C, B+C, or A+B+C, wherein A, B, C can be single or multiple.

[0049] In the related description of the present application, the order of the serial numbers does not mean the order of execution, and part or all of the steps can be executed in parallel or in sequence, and the execution order of each process should be determined according to its function and inherent logic, and should not constitute a limitation on the implementation process of the present application.

[0050] In the related description of the present application, the numerical range should be understood as also specifically disclosing each intermediate value between the upper limit and the lower limit of the range. Each smaller range between any stated value or stated range and any other stated value or intermediate value within the stated range also belongs to the disclosure of the present application. The upper limit and the lower limit of these smaller ranges can be independently included or excluded from the range.

[0051] Unless otherwise defined, all technical / scientific terms used in this application have the meanings commonly used by one of ordinary skill in the art. Although possible, any materials and / or methods similar or equivalent to those described herein can be used in the practice of this application. Additionally, all literature cited in this application is hereby expressly incorporated by reference for the purpose of disclosing and describing the materials and / or methods described therein. In case of conflict between any document incorporated by reference and the technical content of this application, the technical content of this application controls.

[0052] In a first aspect, the embodiments of the present application provide a perovskite nanocrystal array.

[0053] According to Figure 1 As shown in the figure, the perovskite nanocrystal array has a cross-linked polymer nanocolumn array arranged; each of the cross-linked polymer nanocolumns is armored with a plurality of perovskite nanocrystals; and the perovskite nanocrystals are formed in situ by swelling-de-swelling of perovskite precursors. Wherein, the armoring refers to a structure in which the perovskite nanocrystals are encapsulated inside the cross-linked polymer nanocolumn as an armoring layer.

[0054] The embodiments of the present application can effectively achieve the large-scale manufacturing of the nanoscale precision perovskite nanocrystal array by arranging the cross-linked polymer nanocolumn array and in-situ armoring the perovskite nanocrystals in each cross-linked polymer nanocolumn array through swelling-de-swelling. First, the pixel size of the perovskite nanocrystal array can be precisely controlled by adjusting the lattice parameters and pixel size of the cross-linked polymer nanocolumn array. Second, the perovskite nanocrystals can be effectively protected by the armoring structure, which not only endows the perovskite nanocrystal array with excellent environmental stability, but also optimizes the surface optical performance of the perovskite nanocrystal array, and endows the perovskite nanocrystal array with high-quality metasurface optical performance, such as surface lattice resonance with a quality factor of 121, strong coupling Rabi splitting phenomenon, etc.

[0055] In the exemplary scheme of the present disclosure, the cross-linked polymer of the embodiments of the present application also co-polymerizes perovskite passivation monomers. Wherein, the perovskite passivation monomers described in the present application refer to small molecule compounds capable of passivating defect sites of perovskite nanocrystals, which can be preferably 4-vinylpyridine, acrylic acid, dimethylaminoethyl methacrylate, 2-(methylthio) ethyl methacrylate, 2-methacryloyloxyethyl phosphocholine, or carboxybetaine methacrylate, etc.

[0056] It should be noted that the present application co-polymerizes perovskite passivation monomers on the cross-linkable polymer, which effectively optimizes the optical performance of the perovskite nanocrystal array. For example, the perovskite nanocrystal array with 4-vinylpyridine (4-VP) passivation monomers can achieve about 5 times of luminescence enhancement effect.

[0057] In the exemplary scheme of the present disclosure, the cross-linked polymer of the present embodiment is preferably a thermal cross-linked polymer and a photo cross-linked polymer. The thermal cross-linked polymer can be poly(styrene-r-glycidyl methacrylate), and the photo cross-linked polymer can be poly(styrene-r-(4-acryloyloxybenzophenone)). Of course, the two specific polymers described in the present embodiment are only for illustration, and are not intended to limit the polymer materials, which can also be other thermal cross-linked or photo cross-linked polymers.

[0058] It should be noted that the present application does not have special limitations on the synthesis of monomers and specific processes of poly(styrene-r-glycidyl methacrylate) and poly(styrene-r-(4-acryloyloxybenzophenone)). In the present embodiment, styrene (St) and glycidyl methacrylate (GMA) are used as monomers to synthesize poly(styrene-r-glycidyl methacrylate), and styrene (St) and 4-acryloyloxybenzophenone (BPA) are used as monomers to synthesize poly(styrene-r-(4-acryloyloxybenzophenone)). Preferably, a perovskite passivation monomer is added to the synthesis monomers to enhance the optical performance of the perovskite nanocrystal array.

[0059] In the exemplary scheme of the present disclosure, the cross-linked polymer nanocolumn array has the following geometric characteristics:

[0060] (1) The period is 350-600 nm;

[0061] (2) The height is 350-400 nm;

[0062] (3) The area is 1-64 mm 2 .

[0063] It should be noted that the geometric characteristics of the cross-linked polymer nanocolumn array described in the present embodiment can be accurately controlled by the parameters of the template used and the subsequent etching parameters. Selecting the geometric characteristics can effectively optimize the lattice parameters and pixel size, and effectively achieve the large-scale manufacturing of the perovskite nanocrystal array with nanoscale precision.

[0064] In a second aspect, the present embodiment also provides a method for manufacturing the perovskite nanocrystal array of the present application, which preferably comprises the following steps:

[0065] Providing a nanopore array soft template;

[0066] After loading the cross-linkable polymer precursor solution on the nanopore array soft template, the hydrophilic perovskite substrate is subjected to imprinting, and after the imprinting is completed, solvent evaporation and demolding treatment are sequentially performed, so as to form a cross-linkable polymer nanocolumn array precursor on the hydrophilic perovskite substrate;

[0067] After etching treatment is performed on the cross-linkable polymer nanocolumn array precursor, cross-linking of the cross-linkable polymer dot array is initiated, and a cross-linked polymer nanocolumn array is obtained;

[0068] After the cross-linked polymer nanocolumn array is sequentially immersed in a lead bromide DMF solution for swelling, and immersed in a cesium bromide methanol solution for deswelling and inducing in-situ crystallization, and then annealing and drying, the perovskite nanocrystal array is obtained.

[0069] It should be noted that the hydrophilic perovskite substrate of the present application refers to a hydrophilic perovskite substrate obtained by surface hydrophilic modification treatment of a perovskite substrate (such as a silicon wafer, a quartz glass wafer, a glass wafer, etc.). In the present application, the specific method of surface hydrophilic modification is not particularly limited, and the hydrophilic perovskite substrate can be formed as the standard; the size of the perovskite substrate is not particularly limited in the present application, and can be selected according to the design requirements of the perovskite nanocrystal array, for example, the silicon wafer substrate and the quartz glass wafer substrate provided in the embodiments of the present application are 0.5x0.5cm 2 ~5x5cm 2 .

[0070] In the exemplary scheme of the present disclosure, the perovskite substrate is preferably modified by oxygen plasma cleaning or piranha solution cleaning in the embodiments of the present application. When the hydrophilic perovskite substrate is prepared by the oxygen plasma cleaning process, the perovskite substrate can be placed in the cavity of the plasma cleaning machine with air / oxygen pressure of 200-1000 mbar and radio frequency source power of 5-20 W for oxygen plasma cleaning treatment for 60-300 s; when the hydrophilic perovskite substrate is prepared by the piranha solution cleaning process, the perovskite substrate can be soaked in the piranha solution and boiled on a heating plate at a temperature of 100-130℃ for 30-60 min, and then washed with deionized water to neutral.

[0071] It should be noted that the specific parameters for initiating cross-linking of the cross-linkable polymer dot array are not particularly limited in the present application, and can be reasonably set according to the properties of the cross-linkable polymer. For example, the present application initiates thermal cross-linking at 190℃ under inert gas protection / vacuum environment; the initiation of photo-crosslinking is 60W ultraviolet light irradiation for 10min, and the wavelength range is 340-375nm.

[0072] It should be noted that the nano-pore array soft template described in the present application refers to a template capable of imprinting a nano-pillar array, and a PDMS soft template which can be preferably complementary to the target nano-pillar array. In the present application, the silicon nano-pillar array template with a specific array structure can be etched by micro-nano technology, and then the PDMS is used to replicate the silicon nano-pillar array template. Specifically, the SYLGARD 184-PDMS is poured on the silicon nano-pillar array template after the bubbles are removed, and then the PDMS template is cured at a temperature of 80°C for more than 2h, and after the curing process is completed, the PDMS template is peeled off from the silicon nano-pillar array template, and the nano-pore array soft template is obtained.

[0073] It should be noted that the etched silicon nano-pillar array template described in the present application refers to etching a nano-pillar array template on a silicon substrate by an etching method known in the art. For example, the present application etches a nano-pillar array pattern on a silicon substrate by a combination of electron beam exposure and inductively coupled plasma etching technology. Specifically, the electron beam photoresist is spin-coated on the silicon substrate, and the electron beam exposure system is used to expose different period arrays under a beam current of 2nA and a writing field of 1mm×1mm, for example, the periods are 350nm, 400nm, 450nm and 600nm, and the area is 1mm×1mm. After exposure, development is performed, a 20nm chromium sacrificial layer is grown by electron beam evaporation, and the unexposed part of the electron beam photoresist and the chromium sacrificial layer is stripped using an organic solvent such as acetone, leaving the exposed part of the chromium metal pattern. Finally, inductively coupled plasma etching is used to etch a depth of 400nm, and the residual chromium is removed by soaking in a chromium removal solution, to obtain a silicon nano-pillar array template.

[0074] It should be understood in the art that, in order to avoid the adhesion of the nano-pore array soft template to the silicon nano-pillar array template, the silicon nano-pillar array template can be passivated, for example, the silicon nano-pillar array template is treated with 1H, 1H, 2H, 2H-perfluorooctyltrichlorosilane vapor for 2-24h to passivate the surface of the silicon nano-pillar array template.

[0075] It should be noted that the present application does not have special limitations on the specific solvents used to prepare the cross-linkable polymer precursor solution and the concentration of the prepared solution, as long as the cross-linkable polymer precursor solution can diffuse into the nano-pores of the nano-pore array soft template and the cross-linkable polymer dot array is cross-linked. The solvent selected in the present application can be toluene, ethyl acetate, anisole, etc. The concentration of the cross-linkable polymer precursor solution is 1wt%.

[0076] In the exemplary scheme of the present disclosure, the etching treatment of the cross-linkable polymer nanocolumn array precursor can use oxygen plasma etching and reactive ion beam etching. The etching parameters of the oxygen plasma etching are as follows: the pressure in the cavity of the plasma cleaning machine is 60 Pa, the radio frequency source power is 20 W, and the processing time is 240-420 s. The etching parameters of the reactive ion beam etching are as follows: the oxygen flow rate in the cavity of the reactive ion beam etching machine is 35 s.c.c.m., the gas pressure is 60 Pa, the radio frequency source power is 60 W, and the processing time is 20-40 s. The size of the cross-linked polymer nanocolumns can be adjusted by adjusting the etching time, so as to achieve the size adjustment within 168-65 nm.

[0077] In the exemplary scheme of the present disclosure, the molar concentration of the lead bromide DMF solution is preferably 0.5-1 mol / L, including but not limited to 0.5 mol / L, 0.67 mol / L and 1 mol / L; the concentration of the cesium bromide methanol solution is preferably 10-15 mg / mL, including but not limited to 10 mg / mL, 12 mg / mL and 15 mg / mL.

[0078] The present application also provides an application of the perovskite nanocrystal array, specifically, the perovskite nanocrystal array is used for manufacturing a perovskite light-emitting device. The perovskite light-emitting device includes but is not limited to a perovskite light-emitting diode.

[0079] The technical scheme of the present application will be further described below in combination with specific embodiments.

[0080] Embodiment 1

[0081] The present embodiment provides a manufacturing method of a perovskite nanocrystal array, specifically including:

[0082] S1- Hydrophilic modification of the substrate: a quartz glass sheet with a size of 1*1 cm 2 is immersed in an arowana solution and boiled on a hot plate at 130℃ for 1 h, then washed with deionized water until neutral, dried by nitrogen gas flow and dried in an oven at 100℃ for 1 h to obtain a hydrophilic quartz glass sheet.

[0083] S2 - Synthesis of polymer: azobisisobutyronitrile (AIBN, 4.60 mg / 0.028 mmol), 4-cyano-4-(thiobenzoylthio) pentanoic acid (CTBP, 23.33 mg / 0.0835 mmol), styrene (St, 16.525 g / 158.65 mmol), glycidyl methacrylate (GMA, 0.94 g / 6.61 mmol) were added into a 100 mL flask, the flask was sealed and bubbled with high purity nitrogen for 30 min to remove oxygen in the system; the mixed solution was reacted in an oil bath pot with a temperature of 80 °C for 16 h, the reaction was terminated by liquid nitrogen cooling, the obtained viscous mixture was diluted with THF and precipitated with n-hexane for 3 times; the precipitated solid was placed in a vacuum drying box overnight to obtain poly(styrene-r-glycidyl methacrylate), which was prepared into a 1 wt% P(St-r-GMA) polymer toluene solution for standby.

[0084] S3 - Fabrication of PDMS template: after the silicon nanocolumn array template (period 600 nm) was passivated with 1H, 1H, 2H, 2H-perfluorooctyltrichlorosilane in a vacuum dryer for 10 h, SYLGARD 184-PDMS was poured onto the silicon nanocolumn array template after removing bubbles, and cured at a temperature of 80 °C for more than 2 h, after the curing process was completed, it was peeled off from the silicon nanocolumn array template to obtain a nanohole array PDMS template with a surface having a complementary pattern to the silicon nanocolumn array template;

[0085] S4 - Construction of polymer nanocolumn array: the array structure surface of the PDMS template was immersed with 1 wt% P(St-r-GMA) polymer toluene solution for 10 s, and the nanohole array PDMS template immersed with the polymer toluene solution was contacted with a hydrophilic quartz glass for 30 min after being pressed, then the solvent was volatilized and the nanohole array PDMS template was peeled off, and a polymerizable nanocolumn array precursor was formed on the quartz glass;

[0086] S5 - Oxygen plasma etching: the polymerizable nanocolumn array precursor was placed in the cavity of the plasma cleaning machine with air pressure of 60 Pa and radio frequency source power of 20 W, and treated with oxygen plasma for 360 s;

[0087] S6 - Thermal crosslinking of polymer lattice: the polymerizable nanocolumn array precursor was placed in a tube furnace, high purity nitrogen was introduced, and heated at a temperature of 190 °C for 12 h to obtain a crosslinked polymer nanocolumn array;

[0088] S7-In situ growth of perovskite nanocrystals within a cross-linked polymer matrix: Immerse the cross-linked polymer nanopillar array in a 0.67 mol / L PbBr2 solution in DMF for 15 minutes to allow the cross-linked polymer nanopillars to fully swell. Immediately remove the array and immerse it in a 10 mg / mL cesium bromide solution in methanol for 2 minutes to allow the cross-linked polymer nanopillars to deswell and crystallize in situ. Rinse with methanol to remove the perovskite nanocrystals outside the cross-linked polymer nanopillar array.

[0089] S8-Annealing: The quartz glass slide with the perovskite nanocrystal array is annealed at 100°C for 10 minutes and then cooled to obtain the perovskite nanocrystal array.

[0090] The structure of the perovskite nanocrystal array produced in Example 1 was characterized, and the results were Figures 2-3 As shown. Among them, Figure 2 This is a laser confocal microscopy image of the perovskite nanocrystal array; Figure 3 These are the structural color optical photographs of the perovskite nanocrystal array and the optical photographs under ultraviolet light excitation.

[0091] according to Figures 2-3 It can be seen that the perovskite nanocrystal array manufactured in Example 1 has a period of 600 nm and a large uniform array area of ​​8 mm×8 mm; the perovskite nanocrystals emitting green fluorescence are selectively loaded in the cross-linked polymer column array.

[0092] Example 2

[0093] This embodiment provides a method for manufacturing a flexible perovskite nanocrystal array, which specifically includes:

[0094] S1 - Preparation of PDMS flexible substrate: Commercial SYLGARD 184-PDMS was mixed in a mass ratio of Glue A (PDMS matrix): Glue B (curing agent) = 10:1. After removing bubbles in a vacuum desiccator, the mixture was poured into a plastic dish and left at room temperature for approximately 24 hours to obtain a PDMS flexible substrate.

[0095] S2-synthesis of polymer (same as Example 1);

[0096] Preparation of S3-PDMS template (same as in Example 1);

[0097] S4-Constructing polymer nanopillar arrays: The array structure surface of the PDMS template was infiltrated with a polymer toluene solution of P(St-r-GMA) for 10 seconds, and the PDMS template infiltrated with the cross-linkable polymer toluene solution was placed in contact with the PDMS flexible substrate for 30 minutes. The solvent was evaporated and the PDMS template was peeled off to form a polymer nanopillar array precursor on the PDMS flexible substrate.

[0098] S5-oxygen plasma etching (same as example 1);

[0099] S6-thermal crosslinking of the polymer lattice (same as example 1);

[0100] S7-in situ growth of perovskite on the polymer lattice (same as example 1);

[0101] S8-annealing: the PDMS flexible substrate with the perovskite nanocrystal array is annealed at a temperature of 100℃ for 10min and then cooled, and after cooling, a flexible perovskite nanocrystal array is obtained.

[0102] wherein, Figure 4 An optical photo of the flexible perovskite nanocrystal array is shown.

[0103] According to Figure 4 It can be known that the manufacturing method provided by the present application can also construct the perovskite nanocrystal array on a flexible substrate such as PDMS, and obtain a large-area array with a period of 600nm and an area of about 8mm*8mm.

[0104] Example 3

[0105] The present embodiment provides a manufacturing method of a perovskite nanocrystal array, and the difference from example 1 is that the oxygen plasma treatment time in step S5 is 240s, and the rest is the same.

[0106] Example 4

[0107] The present embodiment provides a manufacturing method of a perovskite nanocrystal array, and the difference from example 1 is that the oxygen plasma treatment time in step S5 is 420s, and the rest is the same.

[0108] Example 5

[0109] The present embodiment provides a manufacturing method of a perovskite nanocrystal array, and the difference from example 1 is that the oxygen plasma treatment time in step S5 is 420s, and the rest is the same.

[0110] S1-hydrophilic modification of the substrate (same as example 1);

[0111] Synthesis of S2 -polymer: azobisisobutyronitrile (AIBN, 12.80 mg / 0.01 mmol), 1,4-dioxane (16.3 mL), styrene (2.31 mL / 20 mmol), 4-acryloyloxybenzophenone (BPA, 0.252 g / 1 mmol) were added into a 100 mL flask, the flask was sealed and bubbled with high purity nitrogen for 30 min to remove oxygen in the system; the mixed solution was reacted in an oil bath pot with a temperature of 80 °C for 8 h, the reaction was terminated by liquid nitrogen cooling, the obtained viscous mixture was diluted with THF and precipitated with n-hexane for 3 times; the precipitated solid was put into a vacuum drying oven overnight to obtain poly(styrene-r-(4-acryloyloxybenzophenone)) (P(St-r-BPA)), which was prepared into a 1 wt% P(St-r-BPA) polymer toluene solution;

[0112] Synthesis of S3 -adhesion polymer: azobisisobutyronitrile (AIBN, 12.80 mg / 0.01 mmol), 1,4-dioxane (16.3 mL), styrene (St, 2.31 mL / 20 mmol), 4-acryloyloxybenzophenone (BPA, 0.252 g / 1 mmol) and methacryloyloxypropyltrimethoxysilane (MPS, 248.3 mL / 1 mmol) were added into a 100 mL flask, the flask was sealed and bubbled with high purity nitrogen for 30 min to remove oxygen in the system; the mixed solution was reacted in an oil bath pot with a temperature of 80 °C for 8 h, the reaction was terminated by liquid nitrogen cooling, the obtained viscous mixture was diluted with THF and precipitated with n-hexane for 3 times; the precipitated solid was put into a vacuum drying oven overnight to obtain poly(styrene-r-(4-acryloyloxybenzophenone)-r-methacryloyloxypropyltrimethoxysilane) (P(St-r-BPA-r-MPS));

[0113] S4 -Preparation of PDMS template (same as Example 1);

[0114] S5 -Construction of polymer nanopillar array: P(St-r-BPA-MPS) was dissolved in toluene to prepare a 0.5 wt% adhesion layer solution, 50 μL was added dropwise to a hydrophilic quartz glass slide using a pipette, and then spin-coated at a speed of 4000 rpm and an acceleration of 1000 rpm / s for 60 s, followed by crosslinking by heating at a temperature of 80 °C for 5 min and irradiation with a 365 nm UV lamp at a power of 60 W for 10 min to form a polymer adhesion layer on the surface of the quartz glass slide, then the PDMS template was contacted with the polymer toluene solution for 10 s to allow the PDMS template to adhere to the polymer toluene solution, and the PDMS template with the adhered polymer toluene solution was contacted with the quartz glass slide with the polymer adhesion layer for 30 min, then the solvent was volatilized and the PDMS template was peeled off, forming a polymer nanopillar array precursor on the quartz glass slide;

[0115] S6 - Oxygen plasma etching (same as example 1);

[0116] S7 - Photocrosslinking of polymer lattice: The polymer nanopillar lattice precursor was placed under a 60W 365nm UV lamp for 10min to crosslink the polymer nanopillar lattice;

[0117] S8 - In-situ growth of perovskite nanocrystals within the crosslinked polymer nanopillar lattice (same as example 1);

[0118] S9 - Annealing: The quartz glass slide with perovskite nanocrystal lattice was annealed at 100°C for 10min and then cooled down to obtain the perovskite nanocrystal lattice.

[0119] Example 6

[0120] The present example provides a method for fabricating a perovskite nanocrystal lattice with enhanced luminescence, specifically comprising:

[0121] S1 - Hydrophilic modification of the substrate (same as example 1);

[0122] S2 - Synthesis of copolymeric perovskite passivation monomer crosslinked polymer: Azobisisobutyronitrile (AIBN, 12.80mg / 0.01mmol), 1,4-dioxane (16.3mL), styrene (2.31mL / 20mmol), 4-acryloyloxybenzophenone (BPA, 0.252g / 1mmol) and 4-vinylpyridine (4-VP, 210.2μL / 2mmol) were added into a 100mL flask, the flask was sealed and bubbled with high purity nitrogen for 30min to remove oxygen in the system; the mixed solution was reacted in an oil bath at 80°C for 8h, the reaction was terminated by liquid nitrogen cooling, the obtained viscous mixture was diluted with THF and precipitated with n-hexane for 3 times. The precipitated solid was placed in a vacuum drying oven overnight to obtain poly(styrene-r-(4-acryloyloxybenzophenone)-r-(4-vinylpyridine)) (P(St-r-BPA-r-4VP)), and a 1wt% P(St-r-BPA-r-4VP) polymer toluene solution was prepared;

[0123] S3-Synthesis of Adhesion Polymer: Azobisisobutyronitrile (AIBN, 12.80 mg / 0.01 mmol), 1,4-dioxane (16.3 mL), styrene (St, 2.31 mL / 20 mmol), 4-acryloyloxybenzophenone (BPA, 0.252 g / 1 mmol) and methacryloxypropyltrimethoxysilane (MPS, 248.3 mL / 1 mmol) were added into a 100 mL flask, the flask was sealed and bubbled with high purity nitrogen for 30 min to remove oxygen in the system; the mixed solution was reacted in an oil bath pot with a temperature of 80 °C for 8 h, the reaction was terminated by liquid nitrogen cooling, the obtained viscous mixture was diluted with THF and precipitated with n-hexane for 3 times; the precipitated solid was put into a vacuum drying box overnight to obtain poly(styrene-r-(4-acryloyloxybenzophenone)-r-methacryloxypropyltrimethoxysilane) (P(St-r-BPA-r-MPS));

[0124] S3-Preparation of PDMS template (same as Example 1);

[0125] S4-Construction of polymer nanocolumn array (same as Example 5);

[0126] S5-Oxygen plasma etching (same as Example 1);

[0127] S6-Photo-crosslinking of polymer lattice (same as Example 5);

[0128] S7-In-situ growth of perovskite nanocrystals in polymer lattice (same as Example 1);

[0129] S8-Annealing (same as Example 1), to obtain perovskite nanocrystal array with enhanced luminescence.

[0130] The particle size distribution of the perovskite nanocrystal arrays prepared in Examples 1, 3 and 4 was tested respectively, and the change of the average particle size with the oxygen plasma etching treatment time was analyzed, and the results are shown in FIG. 1. Figure 5 In the figure, a, b and c respectively correspond to the particle size distribution of the perovskite nanocrystal arrays of Examples 3, 1 and 4; d is the curve of the change of the average particle size of the perovskite nanocrystal array with the oxygen plasma etching treatment time.

[0131] According to Figure 5 It can be known that the average particle size of the perovskite nanocrystal array prepared in Example 1 is 89.3 nm; the average particle size of the perovskite nanocrystal array prepared in Example 3 is 167.8 nm; and the average particle size of the perovskite nanocrystal array prepared in Example 4 is 64.8 nm.

[0132] To clarify the performance of the perovskite nanocrystal array manufactured by the embodiment of the present application, the present application also provides Comparative Example 1 (a pure-phase perovskite thin film) and Comparative Example 2 (a perovskite-polymer hybrid thin film), and analyzes the water stability and water contact angle of Example 1 and the two comparative examples.

[0133] Comparative Example 1

[0134] The present comparative example provides a method for manufacturing a pure-phase perovskite thin film, specifically comprising:

[0135] S1 - Hydrophilic modification of the substrate (same as Example 1);

[0136] S2 - Preparation of a lead bromide thin film: spin coating a 0.67 mol / L PbBr2 DMF solution onto a hydrophilic quartz glass at a speed of 2000 rpm for 30 s, and rapidly adding an anti-solvent chlorobenzene onto the hydrophilic quartz glass at the 7th s of the spin coating to produce a tightly uniform PbBr2 thin film;

[0137] S3 - Annealing: annealing the prepared thin film at 90°C for 30 min to completely remove residual solvents;

[0138] S4 - Formation of a pure-phase perovskite thin film: immersing the PbBr2 thin film into a 0.07 mol / L CsBr methanol solution for 10 min, sequentially rinsing with isopropanol and drying with high-purity nitrogen, and then heating to 250°C on an electric furnace and maintaining for 5 min to form a pure-phase perovskite thin film.

[0139] Comparative Example 2

[0140] The present comparative example provides a method for manufacturing a perovskite-polymer hybrid thin film, specifically comprising:

[0141] S1 - Hydrophilic modification of the substrate (same as Example 1);

[0142] S2 - Preparation of a polymer-lead bromide thin film: spin coating a mixed DMF solution of PbBr2 (0.67 mol / L) and P(St-r-GMA) (10 wt%) onto a hydrophilic quartz glass at a speed of 2000 rpm for 30 s;

[0143] S3 - Annealing (same as Comparative Example 1);

[0144] S4 - Formation of a perovskite-polymer hybrid thin film: immersing the polymer-lead bromide thin film into a 0.07 mol / L CsBr methanol solution for 10 min, sequentially rinsing with isopropanol and drying with high-purity nitrogen, and then heating to 250°C on an electric furnace and maintaining for 5 min to form a perovskite-polymer hybrid thin film.

[0145] The water contact angle and water stability of the perovskite nanocrystal array manufactured in Example 1 and the film samples manufactured in Comparative Examples 1-2 were tested respectively (after each sample was immersed in water for a certain time, it was taken out and dried, the fluorescence spectrum under 365 nm ultraviolet light excitation was tested, and the peak value of the fluorescence spectrum was counted), and the results are shown in Table 1. Figures 6-7 Table 1 Figure 6 Fig. 1 is a water contact angle test result diagram; Figure 7 Fig. 2 is a water stability test result diagram.

[0146] According to Table 1 and Fig. 1 and Fig. 2, Figures 6-7 It can be known that the perovskite nanocrystal array prepared by the present application has excellent hydrophobicity and good water stability.

[0147] In order to illustrate the influence of the addition of the perovskite passivation monomer in the present application on the luminescent performance of the perovskite nanocrystal array, the luminescent performance of the perovskite nanocrystal array manufactured in Example 5 and Example 6 was tested, and the results are shown in Table 2. Figure 8 Table 2 Figure 8 Fig. 3 is a luminescent performance test result diagram of the perovskite nanocrystal array manufactured in Example 5 and Example 6.

[0148] According to Table 2 and Fig. 3, Figure 8 It can be known that after the copolymerization of the perovskite passivation monomer in the polymer in Example 6, the fluorescence of the perovskite nanocrystal array is enhanced by about 5 times.

[0149] According to the manufacturing method of Example 5, perovskite nanocrystal arrays with periods of 350 nm, 400 nm and 450 nm were manufactured respectively, and the super surface optical properties of the perovskite nanocrystal arrays with different periods were characterized, and the results are shown in Table 3. Figure 9 Table 3 Figure 9 Fig. 4 is a SEM and super surface optical property characterization result diagram of the perovskite nanocrystal array with different periods (a is an angle-resolved transmission spectrum diagram; b is a 0° angle spectrum diagram).

[0150] According to Table 3 and Fig. 4, Figure 9 It can be known that the resonance wavelength of the 350 nm period perovskite nanometer array is 536.1 nm, and the quality factor Q is 128.3; the resonance wavelength of the 400 nm period perovskite nanometer array is 592.9 nm, and the quality factor Q is 81.46; the resonance wavelength of the 450 nm period perovskite nanometer array is 753.7 nm, and the quality factor Q is 67.25. At the same time, the phenomenon of strong coupling energy band splitting can be observed from the 350 nm period perovskite nanometer array.

[0151] Each embodiment in the present specification is described in a progressive manner, and the same or similar parts between each embodiment can be mutually referred to, and each embodiment mainly illustrates the difference from other embodiments.

[0152] The above examples are only used to illustrate the technical solutions of the present application, and are not intended to limit the present application; although the present application has been described in detail with reference to the foregoing examples, those skilled in the art should understand that the technical solutions recorded in the foregoing examples can still be modified, or some or all of the technical features thereof can be replaced by equivalents; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the present application.

Claims

1. A perovskite nanocrystal array, characterized in that: A cross-linked polymer nanopillar array is provided; Each of the cross-linked polymer nanocolumns is armored with a plurality of perovskite nanocrystals; The perovskite nanocrystals are formed by in-situ crystallization of a perovskite precursor through swelling-deswelling induction.

2. The perovskite nanocrystal array according to claim 1, wherein: The cross-linked polymer is also copolymerized with a perovskite passivation monomer.

3. The perovskite nanocrystal array according to claim 2, wherein: The perovskite passivation monomer is selected from at least one of 4-vinylpyridine, acrylic acid, dimethylaminoethyl methacrylate, 2-(methylthio)ethyl methacrylate, 2-methacryloyloxyethyl phosphorylcholine or methacrylate carboxybetaine.

4. The perovskite nanocrystal array according to claim 1, wherein: The cross-linked polymer comprises a thermal cross-linked polymer and a photo cross-linked polymer; and / or, the thermally cross-linked polymer comprises poly(styrene-r-glycidyl methacrylate); And / or, the photo-crosslinkable polymer comprises poly(styrene-r-(4-acryloyloxybenzophenone)).

5. The perovskite nanocrystal array according to claim 1, wherein: The cross-linked polymer nanocolumn array has the following geometric features: (1) Period is 350-600 nm; (2) Height is 350-400 nm; (3) Area 1 to 64 mm 2 .

6. A method for manufacturing a perovskite nanocrystal array according to any one of claims 1 to 5, Its characteristics include: Providing a nanopore array soft template; After the nanopore array soft template is loaded with a cross-linkable polymer precursor solution, it is used to imprint a hydrophilic perovskite substrate, and after the imprinting is completed, the solvent is volatilized and the mold is released in sequence to form a cross-linkable polymer nanocolumn array precursor on the hydrophilic perovskite substrate; After etching the cross-linkable polymer nanocolumn array precursor, cross-linking of the cross-linkable polymer lattice is initiated to obtain a cross-linked polymer nanocolumn array; The cross-linked polymer nanocolumn array is sequentially immersed in a DMF solution of lead bromide for swelling, and immersed in a methanol solution of cesium bromide for deswelling and inducing in-situ crystallization, and then annealed and dried to obtain the perovskite nanocrystal array.

7. The manufacturing method according to claim 6, wherein: The etching process comprises oxygen plasma etching or reactive ion beam etching; The etching parameters of the oxygen plasma etching are: chamber pressure of 60 Pa, RF source power of 20 W, and processing time of 240 to 420 s; The etching parameters of the reactive ion beam etching are: oxygen flow rate of 35s.ccm, gas pressure of 60Pa, power of 60W, and processing time of 20 to 40s.

8. The manufacturing method according to claim 6, wherein: The method for preparing the nanopore array soft template comprises: etching a silicon nanopillar array template; Injecting SYLGARD 184-PDMS into the silicon nanopillar array template and removing bubbles, followed by curing and demolding, thereby obtaining a nanopore array soft template; The array pattern of the nanohole array soft template is complementary to that of the silicon nanopillar array template.

9. The manufacturing method according to claim 6, wherein: The molar concentration of the lead bromide DMF solution is 0.5-1 mol / L, and the concentration of the cesium bromide methanol solution is 10-15 mg / mL.

10. Use of the perovskite nanocrystal array according to any one of claims 1 to 5 for manufacturing a perovskite light-emitting device.

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