Perovskite fiber membrane modified by double ligands and responded to water stimulation as well as preparation method and application of perovskite fiber membrane

Abstract

The invention belongs to the technical field of anti-counterfeiting optical materials and application thereof, and particularly relates to a double-ligand modified and water stimulus responsive perovskite fiber membrane as well as a preparation method and application thereof. The preparation method comprises the following steps: firstly dissolving metal halide salt BX2 and AX powder in a polar solvent to form a perovskite ABX3 precursor solution, then adding a cyclodextrin cyclic supramolecule and long-chain fatty amine double-ligand system into the obtained precursor solution, and then fully mixing the obtained mixed solution with a high-molecular polymer solution to prepare a spinning solution suitable for electrostatic spinning. And finally, preparing the large-area reversible intelligent fluorescent fiber membrane with the water stimulus response through an electrostatic spinning technology. The water stimulus response intelligent fluorescent fiber membrane based on the perovskite nanocrystals can be applied to the anti-counterfeiting field, such as single information encryption, dual information encryption, anti-counterfeiting labels and high-resolution anti-counterfeiting, is especially suitable for anti-counterfeiting in an underwater environment, and has a wide application prospect.

Description

Technical Field

[0001] The present invention belongs to the technical field of anti-counterfeiting optical materials and their applications, and particularly relates to a perovskite fiber membrane modified by dual ligands and responsive to water stimuli, and a preparation method and application thereof. Background Art

[0002] In the current era of rapid technological development, anti-counterfeiting technology plays a crucial role in various fields, especially in the protection of high-value products, important documents, and intellectual property rights. With the continuous emergence of new materials and encryption technologies, traditional anti-counterfeiting means have gradually become difficult to meet the growing security requirements. As a new type of optoelectronic material, perovskite materials exhibit great application potential due to their unique physical and chemical properties. Perovskite materials not only have excellent properties such as adjustable bandgap, high absorption coefficient, high fluorescence quantum yield, high color purity, high carrier mobility, and long carrier diffusion distance, but also show attractive application prospects in multiple fields such as light-emitting and display lighting devices, solar cells, and detection imaging. In addition, the multiple response characteristics and dynamic color change ability of perovskite materials endow them with great potential in anti-counterfeiting and intelligent material applications, enabling the creation of highly customized anti-counterfeiting labels. However, the stability of perovskite materials is affected by environmental factors, especially the influence of moisture in the environment, which limits the durability and reliability of their practical applications in high-humidity environments and even underwater environments. Therefore, researchers have adopted means such as designing a dual ligand strategy and polymer encapsulation technology to improve the water stability of perovskite materials, aiming to achieve a dynamic reversible transformation of perovskite properties under moisture stimulation.

[0003] Under this background, electrospinning technology, as an efficient and low-cost method for preparing nanofibers, has received extensive attention. Electrospinning technology can stretch and volatilize the solvent of a polymer under a high-voltage electric field to obtain fibers of different sizes. This technology not only has a simple manufacturing device and low spinning cost, but also can prepare a rich variety of nanofibers, thus having a wide application prospect in the field of materials science and technology. Based on the characteristics of electrospinning technology, current researchers focus on the innovative application of the dual ligand confinement effect in the surface passivation and spatial dispersion of perovskite nanocrystals. By carefully designing a synergistic dual ligand system to interact with perovskite materials, the surface properties of perovskite nanocrystals are improved, and the humidity stability and luminescence performance of the materials are greatly enhanced. This strategy makes full use of the design concept of dual ligands, not only enhancing the reliability of perovskite materials in humid and high-temperature environments, but also making their application in the field of anti-counterfeiting materials more advantageous.

[0004] However, there have been no reported applications of using electrospinning technology to prepare perovskite anti-counterfeiting materials, making it a completely new research direction and application field. If electrospinning technology can be combined with the dual-ligand strategy for synthesizing perovskite materials, it is expected to develop a new type of high-performance anti-counterfeiting material that meets the market's demand for high-security, high-reliability, and highly customized anti-counterfeiting solutions. Therefore, exploring the preparation of perovskite nanocrystal anti-counterfeiting materials using electrospinning technology can not only solve the stability challenges faced by current materials in practical applications but also provide new possibilities for future widespread applications in anti-counterfeiting technology and other fields.

[0005] In summary, the present invention aims to effectively improve the performance of perovskite materials by combining electrospinning technology with the method based on the dual-ligand confinement effect, to address the deficiencies of traditional preparation methods, in order to provide technical support for the widespread application of perovskite materials and also open up a brand-new direction for the development of anti-counterfeiting technology. Summary of the Invention

[0006] To overcome the above-mentioned deficiencies of the prior art, the present invention provides a preparation method of a water-stimulus-responsive intelligent fluorescent perovskite fiber membrane based on the dual-ligand strategy. The prepared water-stimulus-responsive intelligent fluorescent fiber membrane based on perovskite nanocrystals can be applied to the anti-counterfeiting field, such as single-message encryption, dual-message encryption, anti-counterfeiting labels, and high-resolution anti-counterfeiting, etc., especially suitable for anti-counterfeiting in underwater environments, and has broad application prospects.

[0007] To achieve the above object, the technical solution adopted by the present invention is:

[0008] The first aspect of the present invention provides a preparation method of a water-stimulus-responsive reversible intelligent fluorescent perovskite fiber membrane based on perovskite nanocrystals, comprising the following steps:

[0009] S11. Dissolve metal halide BX2 and AX powder in a polar solvent to obtain a perovskite ABX3 precursor solution;

[0010] wherein A is selected from Cs + , Rb + , MA + , Na + , FA + , MA + (methylammonium cation, CH3NH3 + ), FA + (formamidinium cation, CH(NH2)2 + ), PEA + (phenethylammonium cation, C6H5CH2NH3 + ), EA + (ethylammonium ion, C2H5NH3 + ) or GA+ (At least one of guanidinium ions, C(NH2)3 + ); B is selected from Bi 3+ , Ge 2+ , Pb 2+ , Cu 2+ , Mn 2+ , Ag + , In 3+ or Sn 2+ ; X is selected from at least one of Cl - , Br - or I - );

[0011] S12. Add long-chain fatty amine ligands and cyclodextrin-based cyclic supramolecular ligands to the precursor solution of S11, and then mix the resulting mixed solution with the polymer solution to prepare a spinning solution;

[0012] The cyclodextrin-based cyclic supramolecular ligand is a cyclodextrin-based compound or a cyclic supramolecule with an inclusion guest molecule structure; the long-chain fatty amine ligand is an organic amine compound with a carbon chain length in the range of C8-C22, including two categories of saturated fatty amines and unsaturated fatty amines (specifically depending on whether there are unsaturated C-C bonds in the long chain); the polymer includes organic solvent-soluble polymers, water-soluble polymers, natural polymers and their derivatives, or special plastics;

[0013] S13. Prepare a water-stimulus-responsive reversible intelligent fluorescent fiber membrane based on perovskite nanocrystals by electrospinning the spinning solution of S12.

[0014] Preferably, in the perovskite nanocrystal ABX3, A is Cs + ; B is Pb 2+ , X is Br - .

[0015] Preferably, the cyclodextrin-based compounds include α-cyclodextrin (α-CD), β-cyclodextrin (β-CD), γ-cyclodextrin (γ-CD), 2-hydroxypropyl-β-cyclodextrin, iodobutyl ether-β-cyclodextrin, quaternary ammonium cation β-cyclodextrin, and the cyclic supramolecules include crown ethers, cucurbiturils, porphyrins, covalent organic framework materials, metal organic framework materials; the long-chain fatty amine ligands include decylamine C 10 H 21 NH2, N-methyldodecylamine C 13 H 29 N, N,N-methyldodecylamine C 14 H 31 N, palmitamine C 16 H 35 N, oleylamine C18 H 37 N。

[0016] Taking quaternary ammonium salt cationic β-cyclodextrin as an example, in the method of the present invention, its contribution to perovskite nanocrystals is mainly reflected in two aspects. First, the anion of the quaternary ammonium salt cationic β-cyclodextrin supramolecule acts as a donor of halide, and undergoes an ion exchange reaction with halide ions in the precursor solution, thereby adjusting the emission wavelength of ABX3 perovskite to different bands. Second, due to the unique supramolecular structure of cyclodextrin and its derivatives, it can have a strong interaction with perovskite nanocrystals, stabilize the lattice structure, and effectively passivate the defects on the crystal surface, thereby inhibiting the non-radiative recombination process, accelerating the radiative recombination rate, and significantly improving the luminescence efficiency and stability of perovskite nanocrystals. In addition, the long-chain fatty amine (such as oleylamine) introduced in this method, as a hydrophobic linear small molecule ligand, is conducive to the uniform dispersion of perovskite nanocrystals in the colloidal solution, and plays an auxiliary modification and size confinement role for perovskite nanocrystals in the present invention.

[0017] Preferably, the high molecular polymer includes polyacrylonitrile (PAN), polyamide (PA), polyvinyl chloride (PVC), polyvinylidene fluoride (PVDF), polystyrene (PS), polybenzimidazole (PBI), polyaniline, acrylonitrile-butadiene-styrene copolymer (ABS), polycarbonate (PC), polymethyl methacrylate (PMMA), polyethylene (PE), polytrimethylene terephthalate (PTT), polypropylene (PP), polyethylene terephthalate (PET), polycaprolactone (PCL), polyhydroxybutyrate (PHA), polysulfone (PSU), polyethyleneimine (PEI), polyvinyl butyral (PVB), polyvinyl alcohol (PVA), polyvinylpyrrolidone (PVP), polyacrylic acid (PAA), polyacrylamide (PAM), polyethylene glycol (PEG), cellulose, chitosan (CS), silk fibroin, collagen, high-temperature nylon special plastics, polyphenylene sulfide (PPS) special plastics.

[0018] More preferably, the high-temperature nylon special plastics and polyphenylene sulfide (PPS) special plastics include barrier plastics, corrosion-resistant plastics, thermoplastic elastomers, rubbers, etc.

[0019] Preferably, for the high molecular polymer soluble in organic solvents, the solvent for dissolving the high molecular polymer is DMF.

[0020] Preferably, the molar concentration of the perovskite ABX3 precursor solution is 0.01 - 1 M. In the precursor solution, the molar concentration ratio of metal halide BX2 to AX is 1:1 or any ratio that can form a non-stoichiometric ratio of perovskite.

[0021] Preferably, the volume ratio of the perovskite ABX3 precursor solution to the polymer solution is 50 - 1000 μL: 1 - 100 mL.

[0022] Preferably, the mass concentration of the polymer solution is 10% - 25%.

[0023] Preferably, the feed ratio of the cyclodextrin-based cyclic supramolecular ligand to the spinning solution is 0.001 - 10 g: 1 - 10 mL; the volume ratio of the long-chain fatty amine ligand to the spinning solution is 10 - 100 μL: 1 - 10 mL.

[0024] Preferably, the polar solvent includes one or a mixture of more of 2-methyltetrahydrofuran (MeTHF), tetrahydrofuran (THF), N-methylpyrrolidone (NMP), 2-methoxyethanol (2-ME), γ-butyrolactone (GBL), acetonitrile (ACN), dimethylformamide (DMF), and dimethyl sulfoxide (DMSO).

[0025] More preferably, the polar solvent is mainly DMF and is mixed with other organic solvents in a ratio of 1:(0 - 1). Specifically, the polar solvent is DMF / DMSO = 4:1.

[0026] Preferably, electrospinning the spinning solution by electrospinning technology means loading the spinning solution into a syringe, then loading the syringe onto a pushing device, pasting a layer of fiber cloth or aluminum foil on the rotating shaft or the receiving plate, and then using an electrospinning machine to electrospin the spinning solution.

[0027] More preferably, during electrospinning, the rotation speed is 150 - 1000 revolutions per minute, the pushing rate of the spinning solution is 0.1 - 20 mL / hour, the initial distance between the needle and the rotating shaft is 1 - 2 cm, the voltage is 8 - 30 kV, and the temperature is 15 - 60 °C.

[0028] More preferably, the syringe specifications are 1, 2.5, 5, 10, 20, 50, 100 mL, etc., and the diameter of the needle hole is 0.1 - 1 mm.

[0029] More preferably, the area of the water-stimulus-responsive intelligent fluorescent fiber membrane based on perovskite nanocrystals prepared can be 5 - 35 cm (width) × 5 - 35 cm (length), and its fiber area is determined by the diameter of the rotating shaft and the size of the receiving plate, and can be adjusted as needed.

[0030] The second aspect of the present invention provides a water-stimulus-responsive reversible intelligent fluorescent fiber membrane based on perovskite nanocrystals prepared by the preparation method described in the first aspect.

[0031] The third aspect of the present invention provides the application of the water-stimulus-responsive reversible intelligent fluorescent fiber membrane based on perovskite nanocrystals described in the second aspect in anti-counterfeiting technology.

[0032] First, the metal halide salts BX2 and AX (A = Cs + , Rb + , etc.; B = Pb 2+ , Sn 2+ , etc.; X = Cl - , Br - , I - , etc.) are dissolved in a polar solvent to obtain an inorganic perovskite ABX3 precursor solution. Then, a dual-ligand system with a synergistic effect (including cyclodextrin-based cyclic supramolecules and long-chain fatty amines) is added to the obtained precursor solution, and then the obtained mixed solution is mixed with a polymer solution to prepare a spinning solution suitable for electrospinning. Finally, the spinning solution is processed by electrospinning technology to prepare a large-area water-stimulus-responsive intelligent fluorescent fiber membrane based on perovskite nanocrystals. Under external moisture stimulation, the photoluminescence fluorescence peak of the prepared water-stimulus-responsive intelligent fluorescent fiber membrane based on perovskite nanocrystals changes from dark blue (460 nm) to cyan (504 nm), and during the reciprocating wet and dry processes, the dynamic luminescence color change can be reversibly cycled multiple times. At the same time, the preparation method of the present invention has the advantages of easily available raw materials, simple operation, strong process controllability, and high repeatability, which is conducive to realizing the industrial-scale production of large-area water-stimulus-responsive reversible intelligent fluorescent fiber membranes. In addition, the present invention also covers the anti-counterfeiting technology applications based on the fiber membrane, including but not limited to single information encryption, dual information encryption, anti-counterfeiting labels, and high-resolution anti-counterfeiting technology, especially anti-counterfeiting applications suitable for underwater environments. The fiber membrane can realize the large-scale production of anti-counterfeiting material raw materials at low cost, is suitable for manufacturing anti-counterfeiting materials in various forms, and has good processability, and can be widely applied to different scenarios.

[0033] The mechanism of water-induced color change is as follows:

[0034] When the water-stimulus-responsive reversible intelligent fluorescent fiber membrane based on perovskite nanocrystals interacts with water molecules, the photoluminescence emission wavelength thereof will change, specifically manifested as a change from dark blue to cyan, as shown in the attached Figure 5 of the specification. Further, by drying and dehumidifying the fluorescent fiber membrane after water treatment, its luminescence color can be reversely changed from cyan to dark blue, thus realizing the reversible conversion of the luminescence color.

[0035] The fourth aspect of the present invention provides a method for constructing a single information encryption system, including the following steps:

[0036] S21. Dissolve metal halide BX2 and AX powder in a polar solvent to obtain a perovskite ABX3 precursor solution;

[0037] where A is selected from Cs + , Rb + , MA + , Na + , FA + , MA + (methylammonium cation, CH3NH3 + ), FA + (formamidinium cation, CH(NH2)2 + ), PEA + (phenethylammonium cation, C6H5CH2NH3 + ), EA + (ethylammonium ion, C2H5NH3 + ), or GA + (guanidinium ion, C(NH2)3 + ); B is selected from Bi 3+ , Ge 2+ , Pb 2+ , Cu 2+ , Mn 2+ , Ag + , In 3+ , or Sn 2+ ; X is selected from at least one of Cl - , Br - , or I - ;

[0038] S22. Add a cyclodextrin-based cyclic supramolecular ligand to the precursor solution of S11, and then mix the resulting mixed solution with a polymer solution to form a spinning solution;

[0039] The cyclodextrin-based cyclic supramolecular ligand is a cyclodextrin-based compound or a cyclodextrin derivative having the same inclusion guest molecule structure; the polymer includes an organic solvent-soluble polymer, a water-soluble polymer, a natural polymer and its derivatives, or a special plastic;

[0040] S23. Prepare a fluorescent fiber membrane based on perovskite nanocrystals by electrospinning the spinning solution of S12;

[0041] S24. Precisely pattern the fluorescent fiber membrane based on perovskite nanocrystals prepared in S23 and the water-stimulus-responsive intelligent fluorescent fiber membrane described in the second aspect into the same dot size, and paste and fix them on a non-fluorescent substrate material according to the target information;

[0042] S25. According to the ASCII binary encoding table of international standards, the prepared water-stimulus-responsive intelligent fluorescent fiber membrane based on perovskite nanocrystals and the fluorescent fiber membrane based on perovskite nanocrystals are precisely sized and cut. The dark blue fluorescent region is defined as the binary code "0", and the cyan fluorescent region is defined as the binary code "1", thereby constructing a binary information encryption array code.

[0043] Preferably, in the perovskite nanocrystal ABX3, A is Cs + ; B is Pb 2+ , and X is Br - .

[0044] Preferably, the cyclodextrin-based cyclic supramolecular ligands include α-cyclodextrin (α-CD), β-cyclodextrin (β-CD), γ-cyclodextrin (γ-CD), 2-hydroxypropyl-β-cyclodextrin, iodobutyl ether-β-cyclodextrin, and quaternary ammonium cation β-cyclodextrin.

[0045] Preferably, the high molecular polymers include polyacrylonitrile (PAN), polyamide (PA), polyvinyl chloride (PVC), polyvinylidene fluoride (PVDF), polystyrene (PS), polybenzimidazole (PBI), acrylonitrile-butadiene-styrene copolymer (ABS), polycarbonate (PC), polymethyl methacrylate (PMMA), polyethylene (PE), polytrimethylene terephthalate (PTT), polypropylene (PP), polyethylene terephthalate (PET), polycaprolactone (PCL), polyhydroxybutyrate (PHA), polysulfone (PSU), polyethyleneimine (PEI), polyvinyl butyral (PVB), polyvinyl alcohol (PVA), polyvinylpyrrolidone (PVP), polyacrylic acid (PAA), polyacrylamide (PAM), polyethylene glycol (PEG), cellulose, chitosan (CS), silk fibroin, collagen, high-temperature nylon special plastics, and polyphenylene sulfide (PPS) special plastics.

[0046] More preferably, the high-temperature nylon special plastics and polyphenylene sulfide (PPS) special plastics include barrier plastics, corrosion-resistant plastics, thermoplastic elastomers, rubbers, etc.

[0047] Preferably, for the organic solvent-soluble high molecular polymer, the solvent for dissolving the high molecular polymer is DMF.

[0048] Preferably, the molar concentration of the perovskite ABX3 precursor solution is 0.01 - 1 M. In the precursor solution, the molar concentration ratio of the metal halide BX2 to AX is 1:1 or any ratio that can form a non-stoichiometric ratio of perovskite.

[0049] Preferably, the volume ratio of the perovskite ABX3 precursor solution to the polymer solution is 50 - 1000 μL: 1 - 100 mL.

[0050] Preferably, the mass concentration of the polymer solution is 10% - 25%.

[0051] Preferably, the feed ratio of the cyclodextrin - like cyclic supramolecular ligand to the spinning solution is 0.001 - 10 g: 1 - 10 mL.

[0052] Preferably, the polar solvent includes one or a mixture of more than one of 2 - methyltetrahydrofuran (MeTHF), tetrahydrofuran (THF), N - methylpyrrolidone (NMP), 2 - methoxyethanol (2 - ME), γ - butyrolactone (GBL), acetonitrile (ACN), dimethylformamide (DMF), and dimethyl sulfoxide (DMSO).

[0053] More preferably, the polar solvent is mainly DMF and is mixed with other organic solvents in a ratio of 1:(0 - 1). Specifically, the polar solvent is DMF / DMSO = 4:1.

[0054] Preferably, electrospinning the spinning solution by electrospinning technology means loading the spinning solution into a syringe, then loading the syringe onto a pushing device, pasting a layer of fiber cloth or aluminum foil on the rotating shaft or the receiving plate, and then using an electrospinning machine to electrospin the spinning solution.

[0055] More preferably, during electrospinning, the rotation speed is 150 - 1000 revolutions per minute, the pushing rate of the spinning solution is 0.1 - 20 mL / hour, the initial distance between the needle and the rotating shaft is 1 - 2 cm, the voltage is 8 - 30 kV, and the temperature is 15 - 60 °C.

[0056] More preferably, the syringe specifications are 1, 2.5, 5, 10, 20, 50, 100 mL, etc., and the diameter of the needle hole is 0.1 - 1 mm.

[0057] More preferably, the area of the prepared fluorescent fiber membrane based on perovskite nanocrystals can be 5 - 35 cm (width) × 5 - 35 cm (length), and its fiber area is determined by the diameter of the rotating shaft and the size of the receiving plate, and can be adjusted as needed.

[0058] The fifth aspect of the present invention provides a method for constructing a dual - information encryption system, including the following steps:

[0059] S31. Use a polymer solution as the spinning solution, and spin the spinning solution through electrospinning technology to make a non-luminescent PS nanofiber membrane. The polymer includes an organic solvent-soluble polymer, a water-soluble polymer, a natural polymer and its derivatives, or a special plastic.

[0060] S32. Prepare a fluorescent fiber membrane based on perovskite nanocrystals according to the method described in the fourth aspect, and then precisely pattern it, together with the PS nanofiber membrane prepared in S31 and the water-stimulus-responsive intelligent fluorescent fiber membrane based on perovskite nanocrystals described in the second aspect, into the same dot size, and paste and fix them on a non-fluorescent substrate material according to the target information, thus obtaining a dual information encryption system.

[0061] Preferably, the polymer includes polyacrylonitrile (PAN), polyamide (PA), polyvinyl chloride (PVC), polyvinylidene fluoride (PVDF), polystyrene (PS), polybenzimidazole (PBI), acrylonitrile-butadiene-styrene copolymer (ABS), polycarbonate (PC), polymethyl methacrylate (PMMA), polyethylene (PE), polytrimethylene terephthalate (PTT), polypropylene (PP), polyethylene terephthalate (PET), polycaprolactone (PCL), polyhydroxybutyrate (PHA), polysulfone (PSU), polyethyleneimine (PEI), polyvinyl butyral (PVB), polyvinyl alcohol (PVA), polyvinylpyrrolidone (PVP), polyacrylic acid (PAA), polyacrylamide (PAM), polyethylene glycol (PEG), cellulose, chitosan (CS), silk fibroin, collagen, high-temperature nylon special plastic, polyphenylene sulfide (PPS) special plastic.

[0062] More preferably, the high-temperature nylon special plastic and the polyphenylene sulfide (PPS) special plastic include barrier plastics, corrosion-resistant plastics, thermoplastic elastomers, rubbers, etc.

[0063] Preferably, the mass concentration of the polymer solution is 10%-25%.

[0064] Preferably, for the organic solvent-soluble polymer, the solvent for dissolving the polymer is DMF.

[0065] Preferably, electrospinning the spinning solution means loading the spinning solution into a syringe, then loading the syringe onto a pushing device, pasting a layer of fiber cloth or aluminum foil on the rotating shaft or the receiving plate, and then using an electrospinning machine to spin the spinning solution.

[0066] More preferably, during spinning, the rotation speed is 150 - 1000 revolutions per minute, the pushing rate of the spinning solution is 0.1 - 20 milliliters per hour, the initial distance between the needle and the rotating shaft is 1 - 2 centimeters, the voltage is 8 - 30 kilovolts, and the temperature is 15 - 60 °C.

[0067] More preferably, the syringe specifications are 1, 2.5, 5, 10, 20, 50, 100 mL, etc., and the diameter of the needle hole is 0.1 - 1 mm.

[0068] More preferably, the area of the prepared perovskite nanocrystal-based fluorescent fiber membrane can be 5 - 35 cm (width) × 5 - 35 cm (length). Its fiber area is determined by the diameter of the rotating shaft and the size of the receiving plate, and can be adjusted as needed.

[0069] The sixth aspect of the present invention provides a method for constructing an anti-counterfeiting label, specifically: first, prepare a perovskite nanocrystal-based fluorescent fiber membrane according to the method described in the fourth aspect, and then perform precise patterning on it with the water-stimulus-responsive intelligent fluorescent fiber membrane based on perovskite nanocrystals described in the second aspect, and then combine them to form an anti-counterfeiting label.

[0070] The seventh aspect of the present invention provides a method for constructing a high-resolution anti-counterfeiting system, specifically: perform different humidity treatments on the water-stimulus-responsive intelligent fluorescent fiber membrane based on perovskite nanocrystals described in the second aspect. The fiber membrane will exhibit a progressive change from dark blue fluorescence to cyan fluorescence, thus forming different information encodings. Then, precisely detect the photoluminescence fluorescence peak with a precision spectrometer and correspond specific wavelengths to specific information to obtain a high-resolution anti-counterfeiting system.

[0071] Compared with the prior art, the beneficial effects of the present invention are:

[0072] The present invention discloses a preparation method of a water-stimulus-responsive intelligent fluorescent perovskite fiber membrane based on a dual-ligand strategy and its application in anti-counterfeiting technology. The preparation method is as follows: First, a metal halide BX2 and AX powder are dissolved in a polar solvent to form a perovskite ABX3 precursor solution. Then, a cyclodextrin-based cyclic supramolecule and a long-chain fatty amine dual-ligand system are added to the obtained precursor solution, and the obtained mixed solution is fully mixed with a polymer solution to prepare a spinning solution suitable for electrospinning. Finally, a large-area water-stimulus-responsive reversible intelligent fluorescent fiber membrane is prepared by electrospinning technology. The preparation method of the present invention has the advantages of easily available raw materials, simple operation, strong process controllability, and high repeatability, which is conducive to realizing the industrial-scale production of large-area luminescent fiber membranes. In addition, the present invention also covers the application of anti-counterfeiting technology based on the fiber membrane, including but not limited to single information encryption, dual information encryption, anti-counterfeiting labels, and high-resolution anti-counterfeiting technology. The fiber membrane can realize the mass production of anti-counterfeiting material raw materials at low cost, is suitable for manufacturing anti-counterfeiting materials in various forms, and has good processability, and can be widely applied to different scenarios.

[0073] The applications of anti-counterfeiting technology are as follows:

[0074] (1) Single information encryption: According to the international standard ASCII binary coding table, precise size cutting is performed on the prepared water-stimulus-responsive reversible intelligent fluorescent fiber membrane 1 based on inorganic perovskite materials and the fluorescent fiber membrane 2 based on inorganic perovskite materials. By setting the dark blue fluorescent area as the binary code "0" and the cyan fluorescent area as the binary code "1", a binary information encryption array code is constructed.

[0075] (2) Dual information encryption: Precise size cutting is performed on the prepared water-stimulus-responsive reversible intelligent fluorescent fiber membrane based on perovskite nanocrystals, the fluorescent fiber membrane based on perovskite nanocrystals, and the PS nanofiber membrane. Subsequently, photoexcitation treatment with a wavelength of 365 nm and water treatment are respectively applied to the above-patterned information. Through these two treatment conditions, patterns with different fluorescence emissions can be induced on the fiber membrane. Further, taking the luminescence color of the fiber membrane under different treatment conditions as an information carrier, the process of secondary information encryption is realized.

[0076] (3) Anti-counterfeiting label: The water-stimulus-responsive reversible intelligent fluorescent fiber membrane based on perovskite nanocrystals can be used to manufacture anti-counterfeiting labels for various commodities. When the label comes into contact with moisture (such as rainwater, high-humidity environment, deep sea), the color of the fiber membrane will change significantly, and this change can be directly observed by the user with the naked eye, thereby realizing the rapid identification of the authenticity of the commodity.

[0077] (4) High-resolution anti-counterfeiting technology: The prepared water-stimulus-responsive reversible intelligent fluorescent fiber membrane based on perovskite nanocrystals has a precisely tunable fluorescence emission peak ranging from 460 nm to 506 nm, which is invisible to the naked eye under normal conditions. It has a high technical threshold and low replicability, and can be used as an optical image anti-counterfeiting technology in combination with a spectrometer. Description of the Drawings

[0078] Figure 1 It is a full-scale drawing of the water-stimulus-responsive intelligent fluorescent fiber membrane based on perovskite nanocrystals;

[0079] Figure 2 It is an SEM image of the water-stimulus-responsive intelligent fluorescent fiber membrane based on perovskite nanocrystals;

[0080] Figure 3 It is a fluorescence microscope image of the water-stimulus-responsive intelligent fluorescent fiber membrane based on perovskite nanocrystals;

[0081] Figure 4 It is the fluorescence quantum yield of the water-stimulus-responsive intelligent fluorescent fiber membrane based on perovskite nanocrystals;

[0082] Figure 5 It is a full-scale drawing of the pH-dependent hydrochromism of the water-stimulus-responsive intelligent fluorescent fiber membrane based on perovskite nanocrystals;

[0083] Figure 6 It is a full-scale drawing of the single-message encryption of the water-stimulus-responsive intelligent fluorescent fiber membrane based on perovskite nanocrystals and an analysis of the decryption process;

[0084] Figure 7 It is a cyclic photoluminescence intensity diagram of the decryption process of the water-stimulus-responsive intelligent fluorescent fiber membrane based on perovskite nanocrystals;

[0085] Figure 8 It is a full-scale drawing of the double-message encryption of the water-stimulus-responsive intelligent fluorescent fiber membrane based on perovskite nanocrystals and an analysis of the decryption process;

[0086] Figure 9 It is a schematic diagram of the anti-counterfeiting label of the water-stimulus-responsive intelligent fluorescent fiber membrane based on perovskite nanocrystals.

[0087] Figure 10 It is a schematic diagram of the high-resolution anti-counterfeiting technology of the water-stimulus-responsive intelligent fluorescent fiber membrane based on perovskite nanocrystals. Detailed Description of the Invention

[0088] The specific embodiments of the present invention are further described below. It should be noted that the description of these embodiments is used to help understand the present invention, but does not constitute a limitation of the present invention. In addition, the technical features involved in each embodiment of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0089] The experimental methods in the following examples are conventional methods unless otherwise specified, and the experimental materials used in the following examples are commercially available unless otherwise specified.

[0090] In view of the problems existing in the existing anti-counterfeiting technology, the present invention proposes a preparation method of a water-stimulation-responsive reversible intelligent fluorescent fiber membrane based on perovskite nanocrystals and its application in anti-counterfeiting technology. According to the large-area water-stimulation-responsive reversible intelligent fluorescent fiber membrane obtained by the preparation method, when the humidity increases, its photoluminescence fluorescence peak will undergo a red shift phenomenon, thereby achieving a visualized water-induced color change effect, and having a fluorescent dual anti-counterfeiting function. Under ultraviolet light excitation, the fiber membrane can display the first anti-counterfeiting information; after water treatment, the second anti-counterfeiting information is presented, which significantly enhances the anti-counterfeiting effectiveness of the fluorescent pattern. In addition, the fiber membrane also has the reversibility of water-induced color change, that is, the fiber membrane that has changed color after water treatment can be restored to the original first anti-counterfeiting information state after dehydration and drying, which effectively improves the sustainable use of anti-counterfeiting materials.

[0091] The following is a further explanation of the process of constructing a water-stimulation-responsive reversible smart fluorescent fiber membrane based on perovskite nanocrystals and its application in the field of anti-counterfeiting in conjunction with Examples 1-5.

[0092] Example 1: A method for preparing a water-stimulation-responsive smart fluorescent perovskite fiber membrane based on a dual-ligand strategy

[0093] The specific preparation method comprises the following steps:

[0094] (1) Weigh 0.05 mmol CsBr and 0.05 mmol PbBr2 and dissolve them in a mixed solvent of 1 mL DMF / DMSO = 4:1, and stir thoroughly (2-3 hours) to obtain a perovskite ABX3 precursor solution;

[0095] (2) Add 50 mg of quaternary ammonium cationic β-cyclodextrin (a type of cyclodextrin) and 20 μL of oleylamine liquid to 1 mL of perovskite ABX3 precursor solution and mix thoroughly;

[0096] (3) preparing a PS (polystyrene) / DMF (N,N-dimethylformamide) polymer solution with a mass fraction of 17%, then taking 450uL of the precursor solution in step (2) and adding it to 3mL of the PS polymer solution, and uniformly mixing to obtain a spinning solution 1;

[0097] (4) Inject the spinning solution 1 into the syringe and install the syringe on the pushing device. Pre-lay a layer of fiber cloth or metal aluminum foil on the rotating shaft or receiving plate. Subsequently, the spinning solution 1 is spun with the aid of an electrospinning device, wherein the rotation speed is 400 rpm, the spinning solution supply rate is 0.5 mL / hour, the distance between the needle and the rotating shaft is maintained at 10 cm, the inner diameter of the needle is 0.4 mm, the spinning voltage is 15 kV, the temperature of the inner cavity of the spinning machine is 30°C, and ventilation is maintained during spinning. Finally, a water-stimulated responsive smart fluorescent fiber membrane based on perovskite nanocrystals is obtained, with a size of 14×25 cm 2 ,like Figure 1 shown.

[0098] Scanning electron microscopy (SEM, Figure 2 ) and fluorescence microscopy ( Figure 3 ) The microstructure of the prepared perovskite nanocrystal-based water-stimulation-responsive smart fluorescent fiber membrane was observed, and its fluorescence quantum yield ( Figure 4 ) was precisely measured and the quantum yield was 64.7%. The observation results showed that the fiber membrane exhibited a uniform outer diameter and surface morphology, and had excellent luminescence efficiency. The fluorescence microscope image clearly showed that the fiber surface emitted light uniformly.

[0099] In addition, after water treatment (such as water spraying, underwater immersion, etc.) of the prepared perovskite nanocrystal-based water-stimulation-responsive smart fluorescent fiber membrane, the photoluminescence color of the fiber surface changed from dark blue to turquoise, and the addition of aqueous solutions with different pH values ​​(pH 2-13) on the fiber membrane surface could induce the occurrence of water-induced color change, such as Figure 5 As shown, it is demonstrated that the fluorescent fiber membrane has hydrochromic potential in various application scenarios.

[0100] Example 2: Construction of a single information encryption system based on water-stimulated intelligent fluorescent fiber membranes of perovskite nanocrystals

[0101] The specific preparation method comprises the following steps:

[0102] (1) Weigh 0.05 mmol CsBr and 0.05 mmol PbBr2 and dissolve them in a mixed solvent of 1 mL DMF / DMSO = 4:1, and stir thoroughly (2-3 hours) to obtain a perovskite ABX3 precursor solution;

[0103] (2) Add 50 mg of quaternary ammonium salt cation β-cyclodextrin (one of the cyclodextrins) to 1 mL of perovskite ABX3 precursor solution and mix well.

[0104] (3) Prepare a 17% (by mass) PS (polystyrene) / DMF (N,N-dimethylformamide) polymer solution. Then, take 450 μL of the precursor solution from step (2) and add it to 3 mL of the PS polymer solution. After uniform mixing, obtain spinning solution 2.

[0105] (4) Inject spinning solution 2 into a syringe and install the syringe on a pushing device. Pre-lay a layer of fiber cloth or aluminum foil on the rotating shaft or receiving plate. Subsequently, perform electrospinning on spinning solution 2 using an electrospinning device, with a rotation speed of 400 revolutions per minute, a spinning solution feeding rate of 0.5 mL per hour, a distance between the needle and the rotating shaft of 10 cm, a needle inner diameter of 0.4 mm, a spinning voltage of 15 kV, a temperature inside the spinning machine cavity of 30 °C, and ventilation maintained during spinning. Finally, obtain a fluorescent fiber membrane based on perovskite nanocrystals, with dimensions of 14×25 cm 2 ;

[0106] (5) Precisely pattern the prepared fluorescent fiber membrane based on perovskite nanocrystals and the water-stimulus-responsive intelligent fluorescent fiber membrane based on perovskite nanocrystals in Example 1 into the same dot size, and paste and fix them on a non-fluorescent substrate material according to the target information. In this example, ordinary black cardboard is selected.

[0107] (6) According to the international standard ASCII binary coding table, precisely cut the prepared water-stimulus-responsive intelligent fluorescent fiber membrane based on perovskite nanocrystals and the fluorescent fiber membrane based on perovskite nanocrystals. Define the dark blue fluorescent region as the binary code "0" and the cyan fluorescent region as the binary code "1", thereby constructing a binary information encryption array code. The physical diagram and its decryption process analysis are as Figure 6 shown.

[0108] Under ultraviolet (365 nm) excitation, the water-stimulus-responsive intelligent fluorescent fiber membrane based on perovskite nanocrystals and the fluorescent fiber membrane based on perovskite nanocrystals emit the same dark blue fluorescence, both corresponding to the same binary code "0". The array code is as follows:

[0109]

[0110] After water treatment, the photoluminescence of the water-stimulus-responsive reversible intelligent fluorescent fiber membrane based on perovskite nanocrystals redshifts to cyan (while the color of the fluorescent fiber membrane based on perovskite nanocrystals remains unchanged), corresponding to the binary code "1", and combines to generate the corresponding encrypted information. The array code is as follows:

[0111]

[0112] Perform a dehumidifying and drying operation on the encrypted information after the above water treatment. Based on the water-stimulated response of perovskite nanocrystals, the photoluminescence of the intelligent fluorescent fiber membrane returns to dark blue fluorescence, and the encrypted information is hidden again. The number of such cycles can reach 20 times.

[0113] Among them, the water treatment includes applications such as spraying the information carrier and soaking it underwater, and dropping various solutions with different properties (acidic solutions, alkaline solutions, water-based liquids such as water). After color change, no obvious difference in color is found. These characteristics make it have high security and difficulty in replication in underwater information encryption.

[0114] Example 3: Construct a dual information encryption system based on a water-stimulated response intelligent fluorescent fiber membrane of perovskite nanocrystals

[0115] The specific preparation method includes the following steps:

[0116] (1) Prepare a PS (polystyrene) / DMF (N,N-dimethylformamide) polymer solution with a mass fraction of 17%. Take 3 mL as spinning solution 3;

[0117] (2) Inject spinning solution 3 into a syringe, and install this syringe on a pushing device. Pre-lay a layer of fiber cloth or aluminum foil on the rotating shaft or receiving plate. Subsequently, perform a spinning operation on spinning solution 3 with the help of an electrospinning device, where the rotation speed is 400 revolutions per minute, the feeding speed of the spinning solution is 0.5 mL / hour, the distance between the needle and the rotating shaft is kept at 10 cm, the inner diameter of the needle is 0.4 mm, the spinning voltage is 15 kV, the temperature inside the spinning machine cavity is 30 °C, and ventilation is maintained during spinning. Finally, a PS nanofiber membrane is obtained, with a size of 14×25 cm 2 ;

[0118] (3) Precisely pattern the obtained PS nanofiber membrane, the fluorescent fiber membrane based on perovskite nanocrystals in Example 2, and the water-stimulated response intelligent fluorescent fiber membrane based on perovskite nanocrystals in Example 1 into the same dot size, and paste and fix them on a non-fluorescent substrate material according to the target information. In this example, the selected material is black cardboard, as Figure 7 shown.

[0119] In a daylight environment, the observable information includes the PS nanofiber membrane of Example 3, the perovskite nanocrystal-based fluorescent fiber membrane of Example 2, and the water-stimulated responsive intelligent fluorescent fiber membrane of Example 1; under ultraviolet (365 nm) excitation, both the water-stimulated responsive intelligent fluorescent fiber membrane based on perovskite nanocrystals and the perovskite nanocrystal-based fluorescent fiber membrane emit a consistent dark blue fluorescence (the PS nanofiber membrane has no fluorescent color), presenting the first layer of encrypted information; after water treatment, the photoluminescence of the water-stimulated responsive intelligent fluorescent fiber membrane based on perovskite nanocrystals redshifts to cyan-green, presenting the second layer of encrypted information, thus achieving dual information encryption. As Figure 8 shown, "88" under bright field becomes "89" after the first decryption by photoluminescence, and then further becomes "35" after the second decryption by water treatment.

[0120] Example 4: Construction of an anti-counterfeiting label for a water-stimulated responsive intelligent fluorescent fiber membrane based on perovskite nanocrystals

[0121] The specific preparation method is as follows:

[0122] According to the required information, precise patterning is performed on the perovskite nanocrystal-based fluorescent fiber membrane of Example 2 and the water-stimulated responsive intelligent fluorescent fiber membrane of Example 1, and they are combined to form an anti-counterfeiting label. The schematic diagram is as Figure 9 shown.

[0123] When the anti-counterfeiting label undergoes water treatment, the true product label of the water-stimulated responsive intelligent fluorescent fiber membrane based on perovskite nanocrystals will emit cyan-green fluorescence; while counterfeit and shoddy products, which do not contain this water-stimulated responsive intelligent fluorescent fiber membrane, will remain dark blue fluorescent after water treatment. Thus, consumers can easily distinguish between true products and counterfeit and shoddy products. Among them, water treatment includes methods such as spraying water on the surface of the commodity label and applying it to underwater anti-counterfeiting labels. For high-value-added underwater equipment, such as diving equipment and underwater detection instruments, the water-stimulated responsive color-changing fluorescent fiber membrane based on perovskite nanocrystals can adapt to harsh underwater environmental conditions, showing excellent properties such as acid-base resistance, flexible mechanical properties, and being processable into various forms, enabling it to firmly adhere to the surface of underwater equipment. Even under long-term immersion or water flow impact, it will not easily fall off or lose its anti-counterfeiting function, thus effectively preventing the emergence of counterfeit and shoddy underwater equipment. By attaching an anti-counterfeiting label made of a water-stimulated responsive color-changing fluorescent fiber membrane based on perovskite nanocrystals to key parts of underwater equipment, operators can use a light source with a specific wavelength to irradiate the anti-counterfeiting label during underwater operations, quickly and accurately identify the authenticity of the equipment according to the change in fluorescent color, and promptly discover and eliminate counterfeit and shoddy products to ensure the safety and efficiency of underwater operations.

[0124] Example 5: Construction of a High-Resolution Anti-Counterfeiting System for a Water-Stimulus Responsive Smart Fluorescent Fiber Membrane Based on Perovskite Nanocrystals

[0125] The specific preparation method is as follows:

[0126] The water-stimulus responsive smart fluorescent fiber membrane based on perovskite nanocrystals in Example 1 is treated with different humidities. The fiber membrane will show a progressive change from dark blue fluorescence to cyan fluorescence, thus constituting different information codes. The photoluminescence fluorescence peaks are accurately detected by means of a precision spectrometer, and specific wavelengths are corresponded to specific information. The schematic diagram is as Figure 10 shown. Figure 10 The high-resolution anti-counterfeiting shown in [Figure]. The gradual change of PL and color coordinates is the change of the emission color under different humidities. The different colored letters on the right correspond to different color information to be distinguished under different humidities.

[0127] In this system, although the two extreme states can be visually distinguished by the naked eye, the intermediate transitional fluorescence color change is subtle and difficult to accurately identify by the naked eye. Therefore, combined with high-precision detection instruments, the rapid response and accurate measurement of environmental humidity are realized by monitoring the color change, so as to realize the fine interpretation of information and construct an anti-counterfeiting system with a higher safety factor.

[0128] The above has described the embodiments of the present invention in detail, but the present invention is not limited to the described embodiments. For those skilled in the art, without departing from the principle and spirit of the present invention, various changes, modifications, substitutions and variations of these embodiments still fall within the protection scope of the present invention.

Claims

1. A preparation method of a water-stimulus-responsive reversible intelligent fluorescent fiber membrane based on perovskite nanocrystals, characterized in that, It includes the following steps: S11. Dissolve metal halide salt BX2 and AX powder in a polar solvent to obtain a perovskite ABX3 precursor solution; wherein A is selected from Cs + , Rb + , MA + , Na + , FA + , MA+, FA+, PEA+, EA+ or GA+; B is selected from Bi 3+ , Ge 2 + , Pb 2+ , Cu 2+ , Mn 2+ , Ag + , In 3+ or Sn 2+ ; X is selected from Cl - , Br - or I - ; S12. Add a long-chain fatty amine ligand and a cyclodextrin-based cyclic supramolecular ligand to the precursor solution in S11, and then mix the resulting mixed solution with a polymer solution to prepare a spinning solution; The cyclodextrin-based cyclic supramolecular ligand is a cyclodextrin-based compound or a cyclic supramolecule having a host-guest molecular structure; the long-chain fatty amine ligand is an organic amine compound with a carbon chain length in the range of C8-C22, including two categories of saturated fatty amines and unsaturated fatty amines; the polymer includes an organic solvent-soluble polymer, a water-soluble polymer, a natural polymer and its derivatives, or a special plastic; S13. Prepare a water-stimulus-responsive reversible intelligent fluorescent fiber membrane based on perovskite nanocrystals by electrospinning the spinning solution in S12.

2. The preparation method of a water-stimulus-responsive reversible intelligent fluorescent fiber membrane based on perovskite nanocrystals according to claim 1, characterized in that, The cyclodextrin compounds include α-cyclodextrin, β-cyclodextrin, γ-cyclodextrin, 2-hydroxypropyl-β-cyclodextrin, iodobutyl ether-β-cyclodextrin, and quaternary ammonium cation β-cyclodextrin. The cyclic supramolecules include crown ethers, cucurbiturils, porphyrins, covalent organic framework materials, and metal organic framework materials. The long-chain fatty amine ligands include decylamine C 10 H 21 NH2, N-methyldodecylamine C 13 H 29 N, N,N-methyldodecylamine C 14 H 31 N, palmitamine C 16 H 35 N, oleylamine C 18 H 37 N. The high molecular polymers include polyacrylonitrile, polyamide, polyvinyl chloride, polyvinylidene chloride, polystyrene, polybenzimidazole, polyaniline, acrylonitrile-butadiene-styrene copolymer, polycarbonate, polymethyl methacrylate, polyethylene, polypropylene glycol terephthalate, polypropylene, polyethylene terephthalate, polycaprolactone, polyhydroxybutyrate, polysulfone, polyethyleneimine, polyvinyl butyral, polyvinyl alcohol-polyvinylpyrrolidone, polyacrylic acid, polyacrylamide, polyethylene glycol, cellulose, chitosan, silk fibroin, collagen, high-temperature nylon special plastics, and polyphenylene sulfide special plastics.

3. The preparation method of a water-stimulus-responsive reversible intelligent fluorescent fiber membrane based on perovskite nanocrystals according to claim 1, characterized in that, The molar concentration of the perovskite ABX3 precursor solution is 0.01-1M; the volume ratio of the perovskite ABX3 precursor solution to the polymer solution is 50-1000 μL: 1-100 mL.

4. The preparation method of a water-stimulus-responsive reversible intelligent fluorescent fiber membrane based on perovskite nanocrystals according to claim 1, characterized in that, The mass concentration of the polymer solution is 10%-25%; the material-liquid ratio of the cyclodextrin-based cyclic supramolecular ligand to the spinning solution is 0.001-10 g: 1-10 mL; the volume ratio of the long-chain fatty amine ligand to the spinning solution is 10-100 μL: 1-10 mL.

5. A water-stimulus-responsive reversible intelligent fluorescent fiber membrane based on perovskite nanocrystals prepared by the preparation method according to any one of claims 1-5.

6. Application of the water-stimulus-responsive reversible intelligent fluorescent fiber membrane based on perovskite nanocrystals according to claim 5 in anti-counterfeiting technology.

7. A construction method of a single - layer information encryption system, characterized in that, It includes the following steps: S21. Dissolve metal halide salt BX2 and AX powder in a polar solvent to obtain a perovskite ABX3 precursor solution; where A is selected from Cs + , Rb + , MA + , Na + , FA + , MA+, FA+, PEA+, EA+ or GA+; B is selected from Bi 3+ , Ge 2 + , Pb 2+ , Cu 2+ , Mn 2+ , Ag + , In 3+ or Sn 2+ ; X is selected from Cl - , Br - or I - ; S22. Add a cyclodextrin-based cyclic supramolecular ligand to the precursor solution in S11, and then mix the resulting mixed solution with a polymer solution to prepare a spinning solution; The cyclodextrin-based cyclic supramolecular ligand is a cyclodextrin-based compound or a cyclodextrin derivative having a host-guest molecular structure; the polymer includes an organic solvent-soluble polymer, a water-soluble polymer, a natural polymer and its derivatives, or a special plastic; S23. Prepare a fluorescent fiber membrane based on perovskite nanocrystals by electrospinning the spinning solution in S12; S24. Precisely pattern the fluorescent fiber membrane based on perovskite nanocrystals prepared in S23 and the water-stimulus-responsive intelligent fluorescent fiber membrane based on perovskite nanocrystals according to claim 5 into the same dot size, and paste and fix them on a non-fluorescent substrate material according to the target information. S25. According to the ASCII binary coding table of international standards, the prepared water-stimulus-responsive intelligent fluorescent fiber membrane based on perovskite nanocrystals and the fluorescent fiber membrane based on perovskite nanocrystals are precisely sized and cut. The dark blue fluorescent region is defined as the binary code "0", and the cyan fluorescent region is defined as the binary code "1", thereby constructing a binary information encryption array code.

8. A method for constructing a dual information encryption system, characterized in that, It includes the following steps: S31. Using a polymer solution as the spinning solution, the spinning solution is spun by electrospinning technology to make a non-luminescent PS nanofiber membrane. The polymer includes an organic solvent-soluble polymer, a water-soluble polymer, a natural polymer and its derivatives, or a special plastic. S32. Prepare the fluorescent fiber membrane based on perovskite nanocrystals according to the method of claim 7, and then precisely pattern it with the PS nanofiber membrane prepared in S31 and the water-stimulus-responsive intelligent fluorescent fiber membrane based on perovskite nanocrystals of claim 5 into the same dot size, and paste and fix it on a substrate material without fluorescence characteristics according to the target information, thus obtaining a dual information encryption system.

9. A method for constructing an anti-counterfeiting label, characterized in that, First, prepare the fluorescent fiber membrane based on perovskite nanocrystals according to the method of claim 7, and then perform precise patterning on it and the water-stimulus-responsive intelligent fluorescent fiber membrane based on perovskite nanocrystals of claim 5, and then combine them to form an anti-counterfeiting label.

10. A method for constructing a high-resolution anti-counterfeiting system, characterized in that, The water-stimulus-responsive intelligent fluorescent fiber membrane based on perovskite nanocrystals of claim 5 is treated with different humidities. The fiber membrane will show a progressive change from dark blue fluorescence to cyan fluorescence, thereby constituting different information codes. Then, the photoluminescence fluorescence peak is precisely detected by means of a precision spectrometer, and a specific wavelength is corresponded to a specific information, thus obtaining a high-resolution anti-counterfeiting system.

Images