Preparation method of organic sn(iv) metal halide reversible luminescence conversion triple anti-counterfeiting material and anti-counterfeiting method

Abstract

This invention relates to the field of encryption and anti-counterfeiting technology, specifically to a method for preparing and using an organic Sn(IV)-based metal halide reversible light-emitting conversion triple anti-counterfeiting material, comprising introducing organic ligands into a Sn(IV)X4 lattice and doping with ns 2 This invention uses Sn(IV) with a high oxidation state to replace Pb(II) in order to obtain anti-counterfeiting materials. 4+ The outer electron configuration is 4d 10 5s 0 The absence of unstable 5s orbitals gives Sn(IV)-based metal halides their typically excellent environmental and thermal stability, providing the compounds with a rigid crystal structure and stereochemical inertness. Furthermore, through ns... 2 Type Sb metal ions 3+ Doping strategies are employed to enhance the luminescence efficiency of low-dimensional organotin (IV)-based metal halides. This invention utilizes Sb... 3+ Ion doping methods are used to modulate the optical properties of compounds. Sb 3+ Ions belong to ns 2 Type metal ions and Sn 4+ With similar ionic radii and unique photophysical properties, it solves the problem of low luminous efficiency in existing luminescent materials.

Description

Technical Field

[0001] This invention relates to the field of encryption and anti-counterfeiting technology, and in particular to a method for preparing and anti-counterfeiting a triple anti-counterfeiting material based on an organic Sn(IV)-based metal halide reversible light-emitting conversion material. Background Technology

[0002] Although lead halide perovskites are easy to synthesize and have high luminescence efficiency, their poor stability and the inherent toxicity of lead severely limit their further applications.

[0003] The current conventional solution is to use Sn(II) instead of Pb(II) to address the toxicity and environmental unfriendliness of Pb. This is because Sn(II) and Pb(II) belong to Group IVA among many lead-free metal halides, giving them similar ionic radii, coordination configurations, and crystal structures, resulting in good optical properties. However, Sn(II) has a 4d electron configuration. 10 5s 2 The presence of high-energy 5s orbital electrons makes them easily oxidized to +4 valence, accompanied by the formation of high defect density, leading to rapid nonradiative relaxation and thus a sharp decrease in luminescence efficiency. Summary of the Invention

[0004] The purpose of this invention is to provide a method for preparing and anti-counterfeiting a triple anti-counterfeiting material based on organic Sn(IV)-based metal halide reversible luminescence conversion, aiming to solve the problems of low luminescence efficiency and poor stability of existing luminescent materials.

[0005] To achieve the above objectives, in a first aspect, the present invention provides a method for preparing an organic Sn(IV)-based metal halide reversible luminescence conversion triple anti-counterfeiting material, comprising the following steps:

[0006] Organic ligands were introduced into the Sn(IV)X4 lattice and doped with ns 2 Type metal ions are used to obtain anti-counterfeiting materials.

[0007] The organic ligand is tetrapropylammonium chloride (TPA). + Two materials, (TPA)SnCl5(H2O)·2H2O and (TPA)2SnCl6, were synthesized.

[0008] The ns 2 The type of metal ion is antimony ion Sb 3+ Synthesis of (TPA)SnCl5(H2O)·2H2O:Sb 3+ And (TPA)2SnCl6:Sb 3+ Two materials.

[0009] The preparation method of (TPA)SnCl5(H2O)·2H2O includes:

[0010] Weigh 1 mmol TPACl and 1 mmol SnCl4 and add them to 5 ml of hydrochloric acid. Dissolve and react at 80 °C for 12 h. After the solution evaporates, take the bottom transparent crystals, wash and dry them to obtain (TPA)SnCl5(H2O)·2H2O.

[0011] Wherein, (TPA)SnCl5(H2O)·2H2O:Sb 3+ The preparation methods include:

[0012] Weigh 1 mmol TPACl, 1 mmol SnCl4, and 0.1 mmol SbCl3 and add them to 5 ml of hydrochloric acid. Dissolve and react at 80 °C for 12 h. After the solution evaporates, collect the transparent crystals at the bottom, wash and dry them to obtain (TPA)SnCl5(H2O)·2H2O:Sb 3+ .

[0013] The preparation method of (TPA)₂SnCl₆ includes:

[0014] Weigh 2 mmol TPACl and 1 mmol SnCl4 and add them to 5 ml DMF to dissolve and react completely. Slowly disperse the ether into the solution to obtain a transparent single crystal. Wash and dry to obtain (TPA)2SnCl6.

[0015] Among them, (TPA)2SnCl6:Sb 3+ The preparation methods include:

[0016] Weigh 2 mmol TPACl, 1 mmol SnCl4, and 0.1 mmol SbCl3 and add them to 5 ml DMF to dissolve and react completely. Slowly disperse diethyl ether into the solution to obtain transparent single crystals. Wash and dry to obtain (TPA)2SnCl6:Sb 3+ .

[0017] Secondly, this invention provides an anti-counterfeiting method for an organic Sn(IV)-based metal halide reversible luminescence conversion triple anti-counterfeiting material, comprising the following steps:

[0018] After drying the anti-counterfeiting material, grind it thoroughly for 15 minutes, then mix it with polydimethylsiloxane (PDMS) or alcohol, and stir vigorously for 15 minutes to ensure the mixture is evenly distributed.

[0019] The mixture is printed onto the surface of an object requiring anti-counterfeiting using screen printing technology in any pattern. After solidification and drying, the anti-counterfeiting effect is achieved.

[0020] This invention discloses a method for preparing an organic Sn(IV)-based metal halide reversible light-emitting conversion triple anti-counterfeiting material, which involves introducing organic ligands into the Sn(IV)X4 lattice and doping with ns. 2 This invention uses Sn(IV) with a high oxidation state to replace Pb(II) in order to obtain anti-counterfeiting materials. 4+ The outer electron configuration is 4d 10 5s 0 The absence of unstable 5s orbitals gives Sn(IV)-based metal halides their typically excellent environmental and thermal stability, providing the compounds with a rigid crystal structure and stereochemical inertness. Furthermore, through ns... 2 Type Sb metal ions 3+ Doping strategies are employed to enhance the luminescence efficiency of low-dimensional organotin (IV)-based metal halides. This invention utilizes Sb... 3+ Ion doping methods are used to modulate the optical properties of compounds. Sb 3+ Ions belong to ns 2 Type metal ions and Sn 4+ With similar ionic radii and unique photophysical properties, it solves the problem of low luminous efficiency in existing luminescent materials. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the preparation process of a series of organic Sn(IV)-based metal halide reversible light-emitting conversion triple anti-counterfeiting materials provided by the present invention.

[0023] Figure 2 This invention provides an organic Sn(IV)-based metal halide ((TPA)2SnCl6:Sb) under different excitation wavelengths. 3+ A schematic diagram showing that different emission curves can be obtained by changing the excitation light of the reversible light-emitting conversion triple anti-counterfeiting material.

[0024] Figure 3 This is a schematic diagram of XRD testing, verifying that the two structures of the organic Sn(IV)-based metal halide provided by this invention can be reversibly transformed through solvent treatment.

[0025] Figure 4The excitation and emission spectra and physical images verify the organic Sn(IV)-based metal halide ((TPA)2SnCl6:Sb provided by this invention). 3+ The compound Sb is a triple anti-counterfeiting material with reversible light-emitting conversion properties. 3+ A schematic diagram showing that -2 emits warm white light when excited by 315nm ultraviolet light and orange light when excited by 365nm ultraviolet light.

[0026] Figure 5 This is a step-by-step diagram of the anti-counterfeiting scheme.

[0027] Figure 6 This is a schematic diagram showing that the anti-counterfeiting pattern can maintain a high luminous intensity and the luminous wavelength will not change even after 10 cycles of processing. Detailed Implementation

[0028] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0029] Please see Figures 1 to 3 First aspect:

[0030] Example 1: This invention provides a method for preparing an organic Sn(IV)-based metal halide reversible light-emitting conversion triple anti-counterfeiting material, comprising the following steps:

[0031] The organic ligand tetrapropylammonium chloride (TPACl) was introduced into the Sn(IV)X4 lattice and doped with ns 2 Type 1 metal ion (Sb) 3+ ), thus obtaining anti-counterfeiting materials.

[0032] Example 2: This invention provides a method for preparing an organic Sn(IV)-based metal halide reversible light-emitting conversion triple anti-counterfeiting material, comprising the following steps:

[0033] Introducing TPA into the Sn(IV)X4 lattice + The cation was prepared by (TPA)SnCl5(H2O)·2H2O (1), and doped with Sb. 3+ Preparation of (TPA)SnCl5(H2O)·2H2O:Sb 3+ , thus obtaining anti-counterfeiting materials.

[0034] Specifically, the preparation method of (TPA)SnCl5(H2O)·2H2O includes:

[0035] Weigh 1 mmol TPACl and 1 mmol SnCl4 and add them to 5 ml of hydrochloric acid. Dissolve and react at 80 °C for 12 h. After the solution evaporates, take the bottom transparent crystals, wash and dry them to obtain (TPA)SnCl5(H2O)·2H2O.

[0036] The (TPA)SnCl5(H2O)·2H2O:Sb 3+ The preparation methods include:

[0037] Weigh 1 mmol TPACl, 1 mmol SnCl4, and 0.1 mmol SbCl3 and add them to 5 ml of hydrochloric acid. Dissolve and react at 80 °C for 12 h. After the solution evaporates, collect the transparent crystals at the bottom, wash and dry them to obtain (TPA)SnCl5(H2O)·2H2O:Sb 3+ .

[0038] Example 3: This invention provides a method for preparing an organic Sn(IV)-based metal halide reversible light-emitting conversion triple anti-counterfeiting material, comprising the following steps:

[0039] Introducing TPA into the Sn(IV)X4 lattice + The cation was prepared as (TPA)2SnCl6(2) and doped with Sb. 3+ Preparation of (TPA)2SnCl6:Sb 3+ , thus obtaining anti-counterfeiting materials.

[0040] Specifically, the preparation method of (TPA)₂SnCl₆ includes:

[0041] Weigh 2 mmol TPACl and 1 mmol SnCl4 and add them to 5 ml DMF to dissolve and react completely. Slowly disperse the ether into the solution to obtain a transparent single crystal. Wash and dry to obtain (TPA)2SnCl6.

[0042] The (TPA)2SnCl6:Sb 3+ The preparation methods include:

[0043] Weigh 2 mmol TPACl, 1 mmol SnCl4, and 0.1 mmol SbCl3 and add them to 5 ml DMF to dissolve and react completely. Slowly disperse diethyl ether into the solution to obtain transparent single crystals. Wash and dry to obtain (TPA)2SnCl6:Sb 3+ .

[0044] By changing different external stimuli (excitation light sources), the (TPA)2SnCl6:Sb 3+Different light emission: This luminescent material exhibits two emission peaks (a high-energy peak at 500 nm and a low-energy peak at 630 nm). Changing the excitation light yields different emission curves. Figure 2 According to the normalization of the low energy peak, it can be seen that the intensity of the high energy peak is the highest when the excitation wavelength is 315nm, at which time white light can be emitted, and orange light can be emitted when the wavelength is 365nm.

[0045] Two materials, (TPA)SnCl5(H2O)·2H2O and (TPA)2SnCl6, can be interconverted after treatment with DMF and hydrochloric acid, and can be used to achieve triple anti-counterfeiting through solvent treatment. Figure 3 XRD test verification (doped samples of two materials (TPA) SnCl5(H2O)·2H2O:Sb) 3+ and (TPA)2SnCl6:Sb 3+ This phenomenon also exists. The equation for the reaction is:

[0046]

[0047]

[0048] Specifically, by adjusting the precursor ratio, the product structure can be controlled, thereby altering the type of luminescent center structure (e.g., Figure 1 ).

[0049] Beneficial effects

[0050] 1. Lead halide perovskites have great potential in information encryption applications, but their poor stability and the inherent toxicity of lead severely limit their further application. The luminescent material proposed in this invention is lead-free, an environmentally friendly material with broad application prospects.

[0051] 2. Many low-dimensional organic-inorganic hybrid lead-free metal halides on the market can respond differently to different photoexcitations, but most of them suffer from poor stability, low luminescence efficiency, irreversible luminescence, and slow response speed. This invention achieves luminescence regulation by doping ns²-type metal ions with multimode dynamic luminescence characteristics into low-dimensional organic Sn(IV)-based metal halides. Its structure is stable, maintaining over 90% of its original luminescence intensity after four months of storage under ambient humidity and temperature. Furthermore, it exhibits high luminescence efficiency, with a fluorescence quantum efficiency as high as 93.36%. Nanosecond-level fluorescence lifetimes measured using an Edinburgh FLS-1000 spectrometer demonstrate that the luminescent material proposed in this invention has a fast response speed.

[0052] 3. This invention utilizes screen printing technology, combined with its different optical responses under various external stimuli and its luminescence characteristics under different configurations, to design a reasonable information encryption model. This results in a new multi-dynamic information encryption technology with fast response speed and high security, representing a novel application of low-dimensional lead-free metal halide information encryption.

[0053] 4. The luminescent material proposed in this invention can achieve triple anti-counterfeiting applications due to the reversible changes in its structure and luminescent properties.

[0054] Please see Figures 4 to 6 Secondly, the present invention provides an anti-counterfeiting method for an organic Sn(IV)-based metal halide reversible luminescence conversion triple anti-counterfeiting material, comprising the following steps:

[0055] After drying the anti-counterfeiting material, grind it thoroughly for 15 minutes, then mix it with polydimethylsiloxane (PDMS) or alcohol, and stir vigorously for 15 minutes to ensure uniform distribution of the mixture. Use screen printing technology to print the mixture onto the surface of the object requiring anti-counterfeiting in any pattern, and achieve the anti-counterfeiting effect after solidification and drying.

[0056] Specifically, the basic principle of anti-counterfeiting is: (1) Two compounds (compound (TPA)SnCl5(H2O)·2H2O:Sb 3+ Compound (TPA)2SnCl6:Sb 3+ (1) The two compounds can be converted to each other by different solutions. (2) The two compounds have different luminescent properties: compound (TPA)SnCl5(H2O)·2H2O:Sb 3+ The compound (TPA)2SnCl6:Sb does not emit light under different ultraviolet light excitations. 3+ It can emit warm white light under 315nm ultraviolet light excitation and orange light under 365nm ultraviolet light excitation. Figure 4 (3) The luminescent material powder proposed in this invention can be well coated by PDMS polymer without changing the luminescent properties. The screen-printed pattern after the powder is mixed with PDMS can resist the treatment of different solvents.

[0057] Figure 5 The anti-counterfeiting scheme is designed based on the above principle: For a 3x3 encrypted dot matrix, we print the compound (TPA)2SnCl6:Sb along one diagonal line. 3+ Powder, the remaining spots use a compound (TPA) dispersed in alcohol: SnCl5(H2O)·2H2O:Sb 3+Printing. When irradiated with 315nm ultraviolet light, only the diagonal areas are bright white, thus obtaining information I. The pattern is treated with a TPACl DMF solution, dried, and then irradiated with 315nm light; all dots become bright white, obtaining information II. Subsequently, irradiation with 365nm light causes all dots to emit orange light, obtaining information III. Treating the pattern with hydrochloric acid and drying restores its chemical composition to its initial state, and it maintains high luminescence properties after any number of cycles (e.g., ...). Figure 6 ).

[0058] The above-disclosed embodiments are merely preferred examples of the preparation method and anti-counterfeiting method of an organic Sn(IV)-based metal halide reversible light-emitting conversion triple anti-counterfeiting material of the present invention. Of course, they should not be construed as limiting the scope of the present invention. Those skilled in the art can understand that implementing all or part of the above-described embodiments and making equivalent changes in accordance with the claims of the present invention are still within the scope of the invention.

Claims

1. A method for preparing an organic Sn(IV)-based metal halide reversible luminescence conversion triple anti-counterfeiting material, characterized in that, Includes the following steps: The organic ligand tetrapropylammonium chloride (TPACl) was introduced into the Sn(IV)Cl4 lattice and doped with ns 2 Type Sb metal ions 3+ The anti-counterfeiting material (TPA) SnCl5(H2O)·2H2O:Sb was obtained. 3+ and (TPA)2SnCl6:Sb 3+ .

2. The preparation method of the organic Sn(IV)-based metal halide reversible luminescence conversion triple anti-counterfeiting material as described in claim 1, characterized in that, The (TPA)SnCl5(H2O)·2H2O:Sb 3+ The preparation methods include: Weigh 1 mmol TPACl, 1 mmol SnCl4, and 0.1 mmol SbCl3 and add them to 5 ml of hydrochloric acid. Dissolve and react at 80 °C for 12 h. After the solution evaporates, collect the transparent crystals at the bottom, wash and dry them to obtain (TPA)SnCl5(H2O)·2H2O:Sb 3+ .

3. The preparation method of the organic Sn(IV)-based metal halide reversible luminescence conversion triple anti-counterfeiting material as described in claim 1, characterized in that, The (TPA)2SnCl6:Sb 3+ The preparation methods include: Weigh 2 mmol TPACl, 1 mmol SnCl4, and 0.1 mmol SbCl3 and add them to 5 ml DMF to dissolve and react completely. Slowly disperse diethyl ether into the solution to obtain transparent single crystals. Wash and dry to obtain (TPA)2SnCl6:Sb 3+ .

4. A method for preventing counterfeiting of an organic Sn(IV)-based metal halide reversible light-emitting conversion triple anti-counterfeiting material, comprising an anti-counterfeiting material prepared by the method described in claim 1, characterized in that... Includes the following steps: After drying the anti-counterfeiting material, grind it thoroughly for 15 minutes, then mix it with polydimethylsiloxane (PDMS) or alcohol, and stir vigorously for 15 minutes to make the mixture evenly distributed. The mixture is printed in any pattern onto the surface of the object requiring anti-counterfeiting using screen printing technology. After solidification and drying, the anti-counterfeiting effect is achieved.

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