High-transparency manganese-based halide luminous organogel and preparation method thereof

Abstract

The invention discloses a high-transparency manganese-based halide luminescent organogel and a preparation method thereof, and the preparation method comprises the following steps: dissolving manganese bromide and isoamyl triphenyl phosphonium bromide in 1-vinyl-2-pyrrolidone to obtain a mixture; adding 1-hydroxycyclohexyl phenyl ketone into the mixture, and carrying out ultrasonic treatment to obtain a transparent solution; and carrying out a photocuring reaction on the transparent solution to obtain the high-transparency manganese-based halide luminous organogel. According to the preparation method, all the raw materials are directly mixed to prepare a uniform and transparent solution, under the irradiation of ultraviolet light, polymerization reaction of monomers is synchronously realized to form a high-transmittance gel network and in-situ generation of a manganese-based halide light-emitting unit, and finally, the amorphous manganese-based halide light-emitting organic gel with high transparency is obtained.

Description

Technical Field

[0001] This invention relates to the field of luminescent organic gel technology, specifically to a highly transparent manganese-based halide luminescent organic gel and its preparation method. Background Technology

[0002] Photopolymerization is a common method for preparing highly transparent polymer gels or resins. This method typically involves mixing photopolymerizable monomers (such as acrylates, methacrylates, and epoxy acrylates) with a crosslinking agent and a photoinitiator to form a transparent precursor solution. After injecting the precursor solution into a mold or coating it onto a substrate, under irradiation with a specific wavelength light source (such as ultraviolet light), the photoinitiator decomposes to generate free radicals or cationic reactive species, initiating monomer polymerization and crosslinking reactions, ultimately curing into a transparent polymer gel or solid with high light transmittance, certain elasticity, and shape adaptability. These materials are widely used in optical devices, biomedical materials, and 3D printing. If luminescent properties are required, pre-synthesized luminescent materials such as quantum dots, organic dyes, or rare-earth complexes are usually physically incorporated into the precursor solution before curing.

[0003] Currently, the preparation of manganese-based halide luminescent organic gels mainly involves pre-synthesizing crystalline or powdered manganese-based halides using solution-phase synthesis or mechanochemical methods (such as ball milling), and then dispersing them as fillers in a polymer matrix (such as gels formed through thermosetting or photocuring) to obtain composite luminescent materials. A typical example is the pre-synthesized (C) halide... 38 H 34 P2) MnBr4 crystal powder is dispersed in a transparent solution containing butyl acrylate, crosslinking agent and photoinitiator, and polymerized by ultraviolet light to form a photocurable gel coated with manganese halide luminescent material. This method has the following limitations: (1) The pre-synthesized luminescent material is prone to aggregation during dispersion, affecting the uniformity and light transmittance of the material; (2) Physical doping may lead to interface defects between the luminescent material and the matrix, reducing luminous efficiency and stability; (3) The step-by-step process (synthesizing the luminescent material first, then preparing the gel) is relatively cumbersome, and it is difficult to accurately control the distribution of the luminescent material in the gel network and the interface interaction; (4) Under the current technology, photocurable gels directly doped with pre-synthesized manganese halide often cannot achieve high luminous efficiency and high light transmittance at the same time. Summary of the Invention

[0004] The purpose of this invention is to provide a highly transparent manganese-based halide luminescent organic gel and its preparation method. The preparation method of this invention involves directly mixing the raw materials to form a homogeneous transparent solution. Under ultraviolet light irradiation, the polymerization reaction of the monomers is simultaneously realized to form a highly transparent gel network and the in-situ generation of manganese-based halide luminescent units, ultimately obtaining an amorphous manganese-based halide luminescent organic gel with high transparency.

[0005] In order to achieve the above-mentioned objectives of the present invention, the following technical solution is adopted:

[0006] The first aspect of this invention provides a method for preparing a highly transparent manganese-based halide luminescent organic gel, the method comprising the following steps:

[0007] (a) Manganese bromide (MnBr2) and isopentyltriphenylphosphine bromide (i-AmTPPBr, C 23 H 26 BrP) is dissolved in 1-vinyl-2-pyrrolidone (NVP) to give a mixture;

[0008] (b) Add 1-hydroxycyclohexylphenyl ketone (HCPK) to the mixture and sonicate to obtain a transparent solution;

[0009] (c) The transparent solution is subjected to photocuring reaction to obtain the highly transparent manganese halide luminescent organic gel.

[0010] Preferably, the molar ratio of manganese bromide to isopentyltriphenylphosphine bromide is 1:(1.8~2.2).

[0011] Preferably, the total mass of manganese bromide and isopentyltriphenylphosphine bromide is 10% to 50% of the mass of the mixture.

[0012] Preferably, the amount of 1-hydroxycyclohexylphenyl ketone added is 1% to 2% of the mass of the mixture.

[0013] Preferably, the ultrasonic treatment time is 3 to 8 minutes.

[0014] Preferably, the photocuring reaction includes irradiation with 365nm ultraviolet light for 3-5 minutes.

[0015] A second aspect of the present invention provides a highly transparent manganese-based halide luminescent organic gel prepared by the above-described preparation method.

[0016] Compared with the prior art, the beneficial effects of the present invention include at least the following:

[0017] The preparation method of this invention avoids the problems of luminescent agglomeration and uneven distribution. Existing techniques typically incorporate pre-synthesized manganese-based halide nanocrystals or powders into the gel precursor solution through physical dispersion. Due to van der Waals forces between particles and high interfacial energy, agglomeration and sedimentation easily occur, leading to concentration fluctuations within the material and significantly affecting the uniformity of luminescence. However, this invention, through the photocuring process, allows the precursor ions (Mn... 2+ ,Br - (etc.) react in situ within the gel network to directly generate uniformly dispersed amorphous manganese halide luminescent clusters, ensuring the spatial uniformity of luminescent units at the molecular scale.

[0018] The preparation method of this invention effectively overcomes the light scattering problem, synergistically achieving high luminous efficiency and high transmittance. Existing technologies, due to the refractive index difference between the pre-synthesized luminescent material and the polymer matrix, coupled with the introduction of interfacial micro-defects by physical doping, easily induce light scattering; aggregates further exacerbate scattering losses, making it difficult to simultaneously achieve high luminous efficiency and high transparency. In this invention, [MnBr4] is generated in situ... 2- The luminescent centers are tightly coupled to the gel network through van der Waals forces, which significantly suppresses interfacial scattering. The precursor liquid itself is a homogeneous and transparent system, and this property is maintained after curing, enabling the material to have a transmittance of over 90% in the visible light region (400–800 nm).

[0019] The preparation method of this invention simplifies the preparation process and improves process controllability and consistency. Existing technologies require multiple separation operations: including pre-synthesis of the luminescent material, purification and drying, dispersion into a gel precursor solution (requiring optimization of concentration, solvent, and ultrasonic parameters), and finally photocuring. This process is cumbersome, and fluctuations in the dispersion process directly affect the uniformity and luminescent properties of the material. The preparation method of this invention adopts a one-step simultaneous synthesis strategy: manganese salt, organic ligand, NVP monomer, and photoinitiator are directly formulated into a homogeneous precursor solution, and the polymerization reaction and luminescent material generation are simultaneously triggered by a single ultraviolet irradiation (e.g., 365 nm), eliminating intermediate steps and achieving centralized and precise control of the ratio, light intensity, and reaction time.

[0020] This invention is compatible with complex structure molding processes and supports diverse device designs. In existing technologies, when constructing complex three-dimensional structures, physically doped luminescent materials are prone to gradient distribution or sedimentation due to the fluidity of the precursor solution or curing shrinkage, which severely limits the design freedom of device configuration. The precursor solution of the preparation method of this invention has low viscosity and rapid photocuring characteristics, which can be well adapted to advanced molding processes such as 3D printing and micro / nano imprinting. The luminescent material is generated in situ simultaneously during the curing process, ensuring that even in complex three-dimensional structures, molecular-level uniform distribution and stable luminescence can be achieved. Attached Figure Description

[0021] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the accompanying drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn to scale.

[0022] Figure 1 The image shows the luminescence of the highly transparent manganese-based halide luminescent organic gel in Example 1 of the present invention under ultraviolet light.

[0023] Figure 2The image shows the luminescence of the highly transparent manganese-based halide luminescent organic gel in Example 2 of the present invention under ultraviolet light.

[0024] Figure 3 The image shows the luminescence of the highly transparent manganese-based halide luminescent organic gel in Example 3 of the present invention under ultraviolet light.

[0025] Figure 4 The PXRD patterns of Mn-C, Mn-PVP, and PVP in the experimental examples of this invention are shown below.

[0026] Figure 5 The FT-IR spectra of Mn-C, Mn-PVP, and PVP in the experimental examples of this invention are shown below.

[0027] Figure 6 The transmittance spectra of Mn-C, Mn-PVP, and PVP in the experimental examples of this invention are shown.

[0028] Figure 7 The excitation (PLE) and emission (PL) spectra of Mn-PVP in the experimental examples of this invention are shown.

[0029] Figure 8 This is a comparison of the fluorescence lifetime of Mn-PVP in the experimental examples of this invention;

[0030] Figure 9 The fluorescence quantum yield of Mn-PVP in the experimental example of this invention is shown. Detailed Implementation

[0031] The embodiments of the technical solution of the present invention will be described in detail below with reference to the examples. The following embodiments are only used to illustrate the technical solution of the present invention more clearly, and are therefore only examples, and should not be used to limit the scope of protection of the present invention.

[0032] It should be noted that, unless otherwise stated, the technical or scientific terms used in this application should have the ordinary meaning as understood by one of ordinary skill in the art to which this invention pertains.

[0033] This invention provides a method for preparing a highly transparent manganese-based halide luminescent organic gel, the method comprising the following steps:

[0034] (a) Manganese bromide (MnBr2) and isopentyltriphenylphosphine bromide (i-AmTPPBr, C 23 H 26 BrP) is dissolved in 1-vinyl-2-pyrrolidone (NVP) to give a mixture;

[0035] (b) Add 1-hydroxycyclohexylphenyl ketone (HCPK) to the mixture and sonicate to obtain a transparent solution;

[0036] (c) The transparent solution is subjected to photocuring reaction to obtain the highly transparent manganese halide luminescent organic gel.

[0037] In one embodiment, the molar ratio of manganese bromide to isopentyltriphenylphosphine bromide is 1:(1.8~2.2).

[0038] In one embodiment, the total mass of manganese bromide and isopentyltriphenylphosphine bromide is 10% to 50% of the mass of the mixture.

[0039] In one embodiment, the amount of 1-hydroxycyclohexylphenyl ketone added is 1% to 2% of the mass of the mixture.

[0040] In one embodiment, the ultrasonic treatment time is 3 to 8 minutes.

[0041] In one embodiment, the photocuring reaction includes irradiation with 365nm ultraviolet light for 3-5 minutes.

[0042] Another embodiment of the present invention provides a highly transparent manganese-based halide luminescent organic gel prepared by the above preparation method.

[0043] The technical solution of the present invention will be further described in detail below through specific embodiments.

[0044] Example 1

[0045] This embodiment describes a method for preparing a highly transparent manganese-based halide luminescent organic gel, the preparation method comprising the following steps:

[0046] (a) Manganese bromide and isopentyltriphenylphosphine bromide are dissolved in 1-vinyl-2-pyrrolidone to obtain a mixture, wherein the molar ratio of manganese bromide to isopentyltriphenylphosphine bromide is 1:2; and the total mass of manganese bromide and isopentyltriphenylphosphine bromide is 10% of the mass of the mixture.

[0047] (b) Add 1-hydroxycyclohexylphenyl ketone to the mixture and sonicate for 5 min to remove foaming, obtaining a clear solution; wherein the amount of 1-hydroxycyclohexylphenyl ketone added is 1% of the mass of the mixture;

[0048] (c) The transparent solution was cured under 365nm ultraviolet light for 3 minutes to obtain the highly transparent manganese halide luminescent organic gel.

[0049] Example 2

[0050] This embodiment describes a method for preparing a highly transparent manganese-based halide luminescent organic gel, the preparation method comprising the following steps:

[0051] (a) Manganese bromide and isopentyltriphenylphosphine bromide are dissolved in 1-vinyl-2-pyrrolidone to obtain a mixture, wherein the molar ratio of manganese bromide to isopentyltriphenylphosphine bromide is 1:2; and the total mass of manganese bromide and isopentyltriphenylphosphine bromide is 30% of the mass of the mixture.

[0052] (b) Add 1-hydroxycyclohexylphenyl ketone to the mixture and sonicate for 5 min to remove foaming, obtaining a clear solution; wherein the amount of 1-hydroxycyclohexylphenyl ketone added is 1.5% of the mass of the mixture;

[0053] (c) The transparent solution was cured under 365nm ultraviolet light for 3 minutes to obtain the highly transparent manganese halide luminescent organic gel.

[0054] Example 3

[0055] This embodiment describes a method for preparing a highly transparent manganese-based halide luminescent organic gel, the preparation method comprising the following steps:

[0056] (a) Manganese bromide and isopentyltriphenylphosphine bromide are dissolved in 1-vinyl-2-pyrrolidone to obtain a mixture, wherein the molar ratio of manganese bromide to isopentyltriphenylphosphine bromide is 1:2; and the total mass of manganese bromide and isopentyltriphenylphosphine bromide is 50% of the mass of the mixture;

[0057] (b) Add 1-hydroxycyclohexylphenyl ketone to the mixture and sonicate for 5 min to remove foaming and obtain a clear solution; wherein the amount of 1-hydroxycyclohexylphenyl ketone added is 2% of the mass of the mixture;

[0058] (c) The transparent solution was cured under 365nm ultraviolet light for 3 min to obtain the highly transparent manganese halide luminescent organic gel (denoted as Mn-PVP).

[0059] Comparative Example 1

[0060] This comparative example illustrates a method for preparing an organic gel, the method comprising the following steps:

[0061] (a) Add 1-hydroxycyclohexylphenyl ketone to 1-vinyl-2-pyrrolidone and sonicate for 5 min to remove foaming, to obtain a clear solution; wherein the amount of 1-hydroxycyclohexylphenyl ketone added is 2% of the mass of the mixture;

[0062] (b) The transparent solution was cured under 365 nm ultraviolet light for 3 min to obtain the organic gel (denoted as PVP).

[0063] Experimental Example

[0064] 1. Obtain the highly transparent manganese-based halide luminescent organic gels prepared in Examples 1-3 respectively, and place them under a 365nm ultraviolet lamp as shown below. Figures 1-3 As shown;

[0065] Figure 1 The luminescence of the highly transparent manganese-based halide luminescent organic gel in Example 1 of the present invention is shown. Figure 2 The luminescence of the highly transparent manganese-based halide luminescent organic gel in Example 2 of this invention; Figure 3 The image shows the luminescence of the highly transparent manganese-based halide luminescent organic gel in Example 3 of this invention.

[0066] Depend on Figures 1-3 It can be seen that under UV irradiation, the luminescence intensity of the gel increases with the increase of the weight percentage of manganese-based halides in the gel.

[0067] 2. X-ray diffraction analysis was performed on manganese-based halide single crystals (Mn-C, (i-AmTPP)2MnBr4 single crystals synthesized by antisolvent diffusion), the highly transparent manganese-based halide luminescent organic gel (Mn-PVP) of Example 3, and the organic gel (PVP) prepared in Comparative Example 1. The analysis results are as follows: Figure 4 As shown;

[0068] Depend on Figure 4 It can be seen that, unlike the sharp diffraction peaks of single crystals, both PVP and Mn-PVP exhibit broadened diffuse peaks, which are typical amorphous diffraction peaks, indicating that the organic gel has an amorphous structure.

[0069] 3. Fourier transform infrared spectroscopy analysis was performed on manganese-based halide single crystals (Mn-C, (i-AmTPP)2MnBr4 single crystals synthesized by antisolvent diffusion), the highly transparent manganese-based halide luminescent organic gel (Mn-PVP) of Example 3, and the organic gel (PVP) prepared in Comparative Example 1. The analysis results are as follows: Figure 5 As shown;

[0070] Depend on Figure 5 It can be seen that the Fourier transform infrared spectra of Mn-PVP, PVP, and Mn-C show that Mn-PVP has the same FT-IR characteristic peaks as PVP and Mn-C. This indicates that Mn-PVP possesses the characteristic structures of both PVP and Mn-C.

[0071] 4. The transmittance spectrum of the highly transparent manganese-based halide luminescent organic gel (Mn-PVP) of Example 3 was analyzed, and the results are as follows: Figure 6 As shown;

[0072] Depend on Figure 6 It can be seen that Mn-PVP has an excellent transmittance of 98% in the visible light band, indicating that it has a high transparency.

[0073] 5. Comparison of excitation (PLE) and emission (PL) spectra and fluorescence lifetime of the highly transparent manganese-based halide luminescent organic gel (Mn-PVP) of Example 3, the results are as follows: Figures 7-8 As shown;

[0074] Figure 7 Excitation (PLE) and emission (PL) spectra; Figure 8 This is a fluorescence lifetime plot;

[0075] Depend on Figures 7-8 It can be seen that Mn-PVP has three excitation peaks located at 326 nm, 365 nm, and 453 nm, respectively, and its emission peak is located at 520 nm. Its fluorescence lifetime at a wavelength of 365 nm is 0.302 ms.

[0076] 6. The fluorescence quantum yield of the highly transparent manganese-based halide luminescent organic gel (Mn-PVP) of Example 3 was determined, and the results are as follows: Figure 9 As shown;

[0077] Depend on Figure 9 It can be seen that the fluorescence quantum yield of 50% Mn-PVP is 14%.

[0078] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be covered within the scope of the claims and specification of the present invention.

Claims

1. A method for preparing a highly transparent manganese-based halide luminescent organic gel, characterized in that, The preparation method includes the following steps: (a) Manganese bromide and isopentyltriphenylphosphine bromide were dissolved in 1-vinyl-2-pyrrolidone to obtain a mixture; (b) Add 1-hydroxycyclohexylphenyl ketone to the mixture and sonicate to obtain a transparent solution; (c) The transparent solution is subjected to photocuring reaction to obtain the highly transparent manganese-based halide luminescent organic gel.

2. The preparation method according to claim 1, characterized in that, The molar ratio of manganese bromide to isopentyltriphenylphosphine bromide is 1:(1.8~2.2).

3. The preparation method according to claim 1, characterized in that, The total mass of manganese bromide and isopentyltriphenylphosphine bromide is 10% to 50% of the mass of the mixture.

4. The preparation method according to claim 1, characterized in that, The amount of 1-hydroxycyclohexylphenyl ketone added is 1% to 2% of the mass of the mixture.

5. The preparation method according to claim 1, characterized in that, The ultrasonic treatment time is 3-8 minutes.

6. The preparation method according to claim 1, characterized in that, The photocuring reaction involves irradiation with 365nm ultraviolet light for 3-5 minutes.

7. The highly transparent manganese-based halide luminescent organic gel prepared by the preparation method according to any one of claims 1 to 6.

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