Zero-dimensional hybrid manganese-based green light emitting material and preparation method and application thereof

Abstract

The invention discloses a zero-dimensional hybrid manganese-based green light emitting material as well as a preparation method and application thereof, and belongs to the technical field of functional hybrid materials. The zero-dimensional hybrid manganese-based green light emitting material is benzyl dimethyl phenyl ammonium chloride manganese bromide, the chemical formula is [BnPh (Me) 2N] 2MnBr4, and benzyl dimethyl phenyl ammonium chloride and manganese bromide are stacked through coulomb interaction. The zero-dimensional hybrid manganese-based green light emitting material obtained by the invention has long light emitting life.

Description

Technical Field

[0001] The present invention relates to the technical field of functional hybrid materials, and more specifically to a zero-dimensional hybrid manganese-based green light emitting material and a preparation method and application thereof. Background Art

[0002] In recent years, hybrid metal halides have attracted widespread attention due to their excellent optoelectronic properties. They have shown great application potential in the fields of solar cells, photodiodes, lasers and detectors. By chemically combining organic cations and inorganic metal halide polyhedra of different sizes and configurations, their inorganic frameworks have been expanded from high dimensions to low dimensions. Among them, low-dimensional hybrid metal halides exhibit outstanding luminescence properties due to the natural quantum confinement effect of their structure, especially zero-dimensional hybrid manganese-based halides. Zero-dimensional hybrid manganese-based halides usually emit strong red or green light and have a narrow half-peak width. The specific luminescence color depends on the Mn 2+ The coordination environment of the ion, when Mn 2+ When the ion is tetrahedral coordinated, the corresponding compound emits green light, while when it is hexahedral coordinated, it emits red light, but their luminescence mechanism is the same as that of Mn 2+ The dd transition of 3d electrons emits light. The dispersed manganese halides in the zero-dimensional hybrid manganese-based halide structure are surrounded by organic cations, showing typical zero-dimensional semiconductor properties. In addition, they have the characteristics of simple synthesis, adjustable structure, excellent performance, and environmental friendliness, which has triggered a wave of preparation of such materials. At present, a large number of zero-dimensional hybrid manganese-based halides constructed by organic cations of different configurations and sizes have been reported, and they are widely used as economical and environmentally friendly luminescent materials, such as in light-emitting diodes, X-ray scintillators, lasers and other fields. Since the luminescence mechanism of this type of compound is generally Mn 2+ The luminescence is caused by the dd electron transition of the reported compounds. The luminescence lifetime is generally in the microsecond level, which greatly limits its application in luminescence, display, sensing and other fields. Summary of the Invention

[0003] In response to the above problems, the present invention provides a zero-dimensional hybrid manganese-based green light emitting material and a preparation method and application thereof. The zero-dimensional hybrid manganese-based green light emitting material has a long luminescence lifetime of milliseconds.

[0004] The first object of the present invention is to provide a zero-dimensional hybrid manganese-based green light emitting material. The zero-dimensional hybrid manganese-based green light emitting material is benzyldimethylphenylammonium chloride manganese bromide, with a chemical formula of [BnPh(Me)2N]2MnBr4. Benzyldimethylphenylammonium chloride and manganese bromide are formed by Coulomb interaction stacking.

[0005] In a preferred embodiment of the present invention, the space group of the zero-dimensional hybrid manganese-based green light emitting material is P twenty one / n , the unit cell parameters of the zero-dimensional hybrid manganese-based green light emitting material are: a =14.9721Å, b =9.7209Å, c =22.6847Å, α =90°, β= 101.6577°, γ =90°.

[0006] In a preferred embodiment of the present invention, the space group of the zero-dimensional hybrid manganese-based green light emitting material is P twenty one / n , the unit cell parameters of the zero-dimensional hybrid manganese-based green light emitting material are: a =14.9042Å, b =9.7138Å, c =22.6055Å, α =90°, β =101.6072°, γ =90°.

[0007] The second object of the present invention is to provide a method for preparing the above-mentioned zero-dimensional hybrid manganese-based green light emitting material, comprising the following steps: The zero-dimensional hybrid manganese-based green light emitting material is prepared by a room temperature volatilization method using water or a mixed solution of water and an alcohol organic solvent as a solvent and benzyldimethylphenylammonium chloride and manganese bromide as raw materials.

[0008] In a preferred embodiment of the present invention, the molar ratio of benzyldimethylphenylammonium chloride to manganese bromide is 1:1 to 1.2.

[0009] In a preferred embodiment of the present invention, in the mixed solution of water and alcoholic organic solvent, the volume ratio of water to the alcoholic organic solvent is 1:1-1.5.

[0010] In a preferred embodiment of the present invention, the ratio of benzyldimethylphenylammonium chloride to solvent is 0.5 mmol: 4 mL to 5 mL.

[0011] The third object of the present invention is to provide the use of the above zero-dimensional hybrid manganese-based green light emitting material in the preparation of light-emitting and display materials.

[0012] Compared with the prior art, the present invention has the following beneficial effects: The zero-dimensional hybrid manganese-based green light-emitting material provided by the present invention has the chemical formula [BnPh(Me)2N]2MnBr4. It is a green block crystal that exhibits strong green light emission and a long carrier lifetime. During preparation, benzyldimethylphenylammonium chloride is used as an organic cationic ligand. Manganese bromide and a solvent are added. A room-temperature solvent evaporation method is used to generate the material through Coulombic interactions between the positively and negatively charged groups or units in the raw materials. This method does not require expensive reaction equipment and can be prepared in an ordinary laboratory using a small amount of raw materials. It has the advantages of simple operation, low cost, and no pollution. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is the XRD pattern of the zero-dimensional hybrid manganese-based green light emitting material with long luminescence lifetime according to Example 1 of the present invention.

[0014] Figure 2 This is a structural diagram of a zero-dimensional hybrid manganese-based green light emitting material with a long luminescence lifetime according to Example 1 of the present invention, wherein a is a zero-dimensional hybrid manganese-based green light emitting material, and b is benzyldimethylphenylammonium chloride.

[0015] Figure 3 This is a thermogravimetric diagram of the zero-dimensional hybrid manganese-based green light emitting material with long luminescence lifetime according to Example 1 of the present invention.

[0016] Figure 4 The UV-visible absorption spectrum and emission spectra under excitation of light of different wavelengths of the zero-dimensional hybrid manganese-based green light emitting material with long luminescence lifetime according to Example 1 of the present invention are shown.

[0017] Figure 5 The position of the luminescent color of the zero-dimensional hybrid manganese-based green light emitting material with a long luminescent lifetime in Example 1 of the present invention in the color coordinates.

[0018] Figure 6 This is a time-resolved fluorescence emission spectrum and lifetime fitting diagram of the zero-dimensional hybrid manganese-based green light-emitting material with long luminescence lifetime according to Example 1 of the present invention. DETAILED DESCRIPTION

[0019] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0020] The luminescence lifetime of zero-dimensional hybrid metal halides is closely related to the configuration and electronic structure of their organic cations. Therefore, designing organic cations with ideal electronic structures and manipulating the band structure of zero-dimensional hybrid manganese halides are key to developing materials with long luminescence lifetimes. However, achieving this goal remains a significant challenge.

[0021] Based on this, the present invention provides a zero-dimensional hybrid manganese-based green light-emitting material with a long luminescence lifetime in the form of green bulk crystals, exhibiting strong green light emission and a long carrier lifetime. This luminescent material is prepared using an organic cationic ligand as a raw material and deionized water as a benign solvent, using a room-temperature solvent evaporation method. This method eliminates the need for expensive reaction equipment and allows the target product to be prepared in a standard laboratory using only a small amount of raw materials. It offers advantages such as simple operation, low cost, and zero pollution.

[0022] Example 1 Preparation of a zero-dimensional hybrid manganese-based green light-emitting material with a long luminescence lifetime: First, manganese bromide tetrahydrate (0.5 mmol, 143 mg), benzyldimethylphenylammonium chloride (0.5 mmol, 124 mg), and distilled water (5 mL) were added to a 15 mL glass vial and ultrasonically stirred until the solution clarified. The vial was then transferred to a fume hood and evaporated at room temperature. After approximately 5 days, green, blocky crystals formed, representing the target crystals.

[0023] The zero-dimensional hybrid manganese-based green light emitting material with long luminescence lifetime prepared in Example 1 was characterized by XRD powder diffraction, with a maximum voltage of 40KV. Turn on the instrument switch, then open the test software and turn on the X-ray light source. Place the sample on a clean silicon wafer, flatten it with a scraper, press the "Door Lock" button, and open the door after two beeps. Place the silicon wafer with the sample, close the door, set the test conditions, scan rate of 3deg / min, 2θ of 5°~45°, and obtain the experimental spectrum. The results are as follows: Figure 1 As shown. Figure 1 It can be clearly seen that the XRD pattern of the experimentally synthesized crystals is almost consistent with the results of the theoretical calculation value fitting, indicating that the purity of the obtained crystals is very high.

[0024] The zero-dimensional hybrid manganese-based green light emitting material with long luminescence lifetime of the present invention is a centrosymmetric, zero-dimensional bulk crystal, named benzyldimethylphenylammonium manganese bromide, with the chemical formula [BnPh(Me)2N]2MnBr4, and the structural formula is as follows: Figure 2 Its space group is P twenty one / n , the crystal cell parameters are: a =14.9721(15)Å, b =9.7209(10)Å, c =22.6847(2)Å,α= 90°, β=101.6577(10)°, γ =90°. In its structure, each Mn²⁺ ion coordinates with four adjacent Br⁻ ions to form an independent tetrahedron. Each [MnBr4] 2- The tetrahedrons are all counter-cations BnPh(Me)2N + Surrounded by, the two are stacked together completely through Coulomb interaction.

[0025] The thermal stability of the zero-dimensional hybrid manganese-based green light emitting material with long luminescence lifetime prepared in Example 1 was tested using a thermogravimetric analyzer. 6 mg of sample was weighed and the test was performed in air atmosphere with a scanning range of 25°C to 800°C and a scanning rate of 10°C / min. The results are shown in Figure 2. Figure 3 As shown, from Figure 3 It can be clearly seen that the prepared crystals have good thermal stability and the decomposition temperature is about 171 °C.

[0026] The ultraviolet-visible absorption spectrum and fluorescence emission spectrum of the zero-dimensional hybrid manganese-based green light emitting material with long luminescence lifetime prepared in Example 1 were tested using an ultraviolet-visible absorption spectrometer and a fluorescence spectrometer. The results are as follows: Figure 4 As shown. It can be found that there are obvious absorption peaks at 361nm, 375nm, 436nm and 450nm in its absorption spectrum. According to the tetrahedral coordination environment of Mn 2+ Energy level splitting diagram, their four absorption peaks correspond to the transitions between the ground state and excited state energy levels of 6A1→4E(D), 6A1→4T2(D), 6A1→4A1(G), 4E(G) and 6A1→4A2(G). Under ultraviolet light excitation, the target compound emits strong green light with an emission center of 515.6nm and a half-peak width of 51nm. Under excitation of light of different wavelengths, its emission peak position remains consistent, and the emission intensity decreases slightly with increasing excitation wavelength. The reason is that as the excitation wavelength increases, the excitation energy decreases. The position of the green light emitted by the target compound in the color coordinate is (0.19, 0.68), which is very close to the standard green light (0.3, 0.6), such as Figure 5 shown.

[0027] The time-resolved emission spectrum and fluorescence quantum yield of the zero-dimensional hybrid manganese-based green light emitting material with long luminescence lifetime prepared in Example 1 were tested using a fluorescence spectrometer. The time-resolved emission spectrum results are shown in Figure 2. Figure 6 As shown, the average carrier lifetime of the target material, obtained by fitting a double exponential decay function, is 1.3 ms. This value is significantly higher than the highest value (0.56 ms) reported for zero-dimensional hybrid manganese bromine compounds. This indicates that the target compound has an exceptionally long luminescence lifetime. Furthermore, the target compound exhibits a fluorescence quantum yield of 62.39%.

[0028] Example 2 A zero-dimensional hybrid manganese-based green light-emitting material with a long luminescence lifetime can also be prepared by the following method: first, manganese bromide tetrahydrate (0.5 mmol, 143 mg), benzyldimethylphenylammonium chloride (0.5 mmol, 124 mg), ethanol (2 mL), and distilled water (2 mL) are added to a 15 mL glass vial and ultrasonically stirred until the solution is clear; then the glass vial is transferred to a fume hood for evaporation at room temperature. After about 4 days, pale yellow target crystals are formed. Its space group is P twenty one / n , the crystal cell parameters are: a =14.9042(10)Å, b =9.7138(10)Å, c =22.6055(3)Å, α =90°, β =101.6072(8)°, γ =90°.

[0029] Example 3 A zero-dimensional hybrid manganese-based green light-emitting material with a long luminescence lifetime can also be prepared by the following method: Manganese bromide tetrahydrate (0.6 mmol, 172 mg), benzyldimethylphenylammonium chloride (0.5 mmol, 124 mg), ethanol (2.5 mL), and distilled water (2 mL) are first added to a 15 mL glass vial and ultrasonically stirred until the solution is clear. The vial is then transferred to a fume hood and evaporated at room temperature. The target pale yellow crystals form after approximately four days.

[0030] Example 4 A zero-dimensional hybrid manganese-based green light-emitting material with a long luminescence lifetime can also be prepared by the following method: Manganese bromide tetrahydrate (0.55 mmol, 158 mg), benzyldimethylphenylammonium chloride (0.5 mmol, 124 mg), ethanol (3 mL), and distilled water (2 mL) are first added to a 15 mL glass vial and ultrasonically stirred until the solution is clear. The vial is then transferred to a fume hood and evaporated at room temperature. After approximately four days, pale yellow crystals of the desired substance form.

[0031] Li Zhigang et al. published "Giant Emission Enhancement from Hybrid Manganese Bromide Via Pressure-Induced Band-Edge Carrier Reconfiguration" in "Advanced Functional Materials" Volume 34, 2024. The compound [BPPH]2MnBr4 synthesized with bis(triphenylphosphine)imide (BPPH) as a ligand has a fluorescence lifetime of 0.15ms; Li Kai et al. published "Temperature- and Pressure-Dependent Emissions and Crystal-Glass Transition of a Hybrid Manganese Bromide" in "Chinese Journal of Chemistry" Volume 43, 2025. The compound [4-MTPP]2MnBr4 synthesized with 4-methoxybenzyltriphenylphosphine (4-MTPP) as a ligand has a fluorescence lifetime of 0.37ms.

[0032] The performance of [BnPh(Me)2N]2MnBr4 prepared in Example 1 of the present invention is 1.3ms, which is better than [BPPH]2MnBr4 and [4-MTPP]2MnBr4. The zero-dimensional hybrid manganese-based green light emitting material prepared by the present invention has a long luminescence lifetime.

[0033] Although the preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0034] Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if such changes and modifications fall within the scope of the claims and their equivalents, the present invention is intended to include such changes and modifications.

Claims

1. A zero-dimensional hybrid manganese-based green light emitting material, characterized in that: The zero-dimensional hybrid manganese-based green light emitting material is benzyldimethylphenylammonium chloride manganese bromide, with the chemical formula [BnPh(Me)2N]2MnBr4. Benzyldimethylphenylammonium chloride and manganese bromide are stacked through Coulomb interaction.

2. The zero-dimensional hybrid manganese-based green light emitting material according to claim 1, characterized in that: The space group of the zero-dimensional hybrid manganese-based green light emitting material is P twenty one / n , the unit cell parameters of the zero-dimensional hybrid manganese-based green light emitting material are: a =14.9721Å, b =9.7209Å, c =22.6847Å, α =90°, β= 101.6577°, γ =90°.

3. The zero-dimensional hybrid manganese-based green light emitting material according to claim 1, characterized in that: The space group of the zero-dimensional hybrid manganese-based green light emitting material is P twenty one / n , the unit cell parameters of the zero-dimensional hybrid manganese-based green light emitting material are: a =14.9042Å, b =9.7138Å, c =22.6055Å, α =90°, β =101.6072°, γ =90°.

4. A method for preparing the zero-dimensional hybrid manganese-based green light emitting material according to claim 1, characterized in that: The following steps are involved: The zero-dimensional hybrid manganese-based green light emitting material is prepared by a room temperature volatilization method using water or a mixed solution of water and an alcohol organic solvent as a solvent and benzyldimethylphenylammonium chloride and manganese bromide as raw materials.

5. The method for preparing a zero-dimensional hybrid manganese-based green light emitting material according to claim 4, characterized in that: The molar ratio of benzyldimethylphenylammonium chloride to manganese bromide is 1:1~1.

2.

6. The method for preparing a zero-dimensional hybrid manganese-based green light emitting material according to claim 4, characterized in that: In the mixed solution of water and alcohol organic solvent, the volume ratio of water to the alcohol organic solvent is 1:1~1.

5.

7. The method for preparing a zero-dimensional hybrid manganese-based green light emitting material according to claim 4, characterized in that: The ratio of benzyldimethylphenylammonium chloride to solvent is 0.5mmol:4mL~5mL.

8. Use of the zero-dimensional hybrid manganese-based green light emitting material according to claim 1 in the preparation of luminescent and display materials.

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