Multicolor luminous hydrogen bond-organic framework material and preparation method thereof

Abstract

The invention provides a multicolor light-emitting hydrogen bond-organic framework material, which is formed by connecting an organic ligand and an organic solvent molecule through a hydrogen bond, the chemical formula of the multicolor light-emitting hydrogen bond-organic framework material is [(L) x (G) y (R) z], L is tetra [4-(3, 5-dicarboxyphenyl)] tetraphenylethylene, G represents a good solvent, and R represents a poor solvent; x is 0.5-1, y is 1-4, and z is 1-2. The novel hydrogen bond-organic framework material is constructed by introducing solvent molecules, and abundant hydrogen bonds are provided by introducing the solvent, so that the rigidity of the framework is improved, the conformation of organic molecules is changed, the non-radiative energy loss of the organic molecules is inhibited, and the light-emitting quantum yield of the hydrogen bond-organic framework material is greatly improved; and the highest light-emitting quantum yield can reach 100%. The multicolor light-emitting hydrogen bond-organic framework material can achieve tuning of light-emitting colors through pressure treatment engineering, the method is simple and environmentally friendly, and the repeatability of light-emitting tuning is good.

Description

Technical Field

[0001] The present invention belongs to the technical field of preparation of multicolor luminescent materials, and in particular relates to a multicolor luminescent hydrogen bond-organic framework material and a preparation method thereof. Background Art

[0002] For a long time, constructing multicolor photoluminescent materials with tunable properties has been a research goal that has attracted much attention from researchers, because these materials have broad application potential in lighting displays, chemical and biological sensors, bioimaging, information encryption and high-density optical storage.

[0003] Hydrogen-bonded organic frameworks (HOFs) are a class of crystalline porous framework materials composed of organic or metal-organic building blocks connected by hydrogen bonds. In addition to hydrogen bonds, other intermolecular forces such as π-π stacking, electrostatic interactions, and van der Waals forces also play a very important role in the construction and stability of HBOFs. This type of material has the advantages of adjustable pore structure and function, low biotoxicity, mild synthesis conditions, high crystallinity, solvent processability, easy repair and regeneration, and is widely used in gas adsorption and separation, heterogeneous catalysis, fluorescence and sensing, biological applications and other fields. The diversity of its organic building blocks and the infinite combination characteristics make HBOFs an excellent platform for achieving tunable and controllable luminescence behavior. At present, the research on multicolor luminescent materials based on HBOFs is still in its early stages, and the control methods are single.

[0004] For example, the patent application with publication number CN112920794A discloses a hydrogen bond organic framework composite luminescent material, including a mass molar ratio of 20-40 mg: 4×10 -7 The patent application discloses a hydrogen-bonded organic framework material and an organic red dye. The hydrogen-bonded organic framework material is prepared from an organic ligand and N,N-dimethylformamide in a molar volume ratio of 0.000225 mol to 0.8-1.2 L. Yellow light emission is achieved by adjusting the amount of dye and main framework material, with a luminescence quantum yield of 10.9%. When packaged into a commercial 460nm blue LED chip, white light emission is achieved.

[0005] For example, the patent application with publication number CN117986611A discloses two isostructural pentaerythrene octacarboxylic acid-based hydrogen-bonded organic framework composite materials with white light emission. The material is a complex of the hydrogen-bonded organic framework and the organic dyes 3,6-di(2-thienyl)diketopyrrolopyrrole and 9-anthraldehyde.

[0006] Achieving tunable multicolor luminescence performance of hydrogen-bonded organic framework materials based on a single organic ligand remains challenging. Therefore, developing effective strategies to achieve tunable emission colors of a single luminescent material is crucial. In addition, the luminescence quantum yield of hydrogen-bonded organic framework materials also needs to be improved. Summary of the Invention

[0007] Based on the above technical problems existing in the prior art, the present invention provides a multi-color luminescent hydrogen bond-organic framework material and a preparation method thereof.

[0008] The present invention provides a multi-color luminescent hydrogen bond-organic framework material, which is formed by organic ligands and organic solvent molecules connected by hydrogen bonds. The chemical formula of the multi-color luminescent hydrogen bond-organic framework material is [(L) x (G) y (R) z ], wherein L is tetrakis[4-(3,5-dicarboxyphenyl)]tetraphenylethylene, G represents a good solvent, R represents a poor solvent; x=0.5~1, y=1~4, z=1~2.

[0009] The good solvent refers to a solvent that has good solubility for L, and the poor solvent refers to a solvent that has weak solubility for L.

[0010] The structural formula of tetrakis[4-(3,5-dicarboxyphenyl)]tetraphenylethylene is as shown in Formula I:

[0011]

[0012] Preferably, when x=0.5, y=1, and z=1, the fluorescence quantum yield of the multicolor luminescent hydrogen bond-organic framework material is the highest, reaching 100%.

[0013] Preferably, the good solvent is one of N,N-dimethylformamide, N,N-dimethylacetamide and N,N-diethylformamide.

[0014] Preferably, the poor solvent is one of methanol, acetone, tetrahydrofuran, ethanol, dimethyl sulfoxide and dichloromethane.

[0015] The present invention provides a method for preparing the multicolor luminescent hydrogen bond-organic framework material, comprising the following steps:

[0016] The organic ligand L is dissolved in a good solvent G, and then a poor solvent R is added, and the mixture is allowed to stand for precipitation to obtain the multi-color luminescent hydrogen bond-organic framework material. The prepared multi-color luminescent hydrogen bond-organic framework material is a green rectangular block crystal.

[0017] Preferably, the volume ratio of the good solvent G to the poor solvent R is 1:5-10.

[0018] Preferably, the concentration of the organic ligand L in the good solvent G is 2 to 10 mmol / L.

[0019] Preferably, the standing time is 7 to 15 days.

[0020] The present invention also provides a method for tuning the fluorescence emission color of the multi-color luminescent hydrogen bond-organic framework material, using the multi-color luminescent hydrogen bond-organic framework material as the initial material, and pressurizing the initial material through a diamond anvil press, thereby changing the fluorescence emission color of the multi-color luminescent hydrogen bond-organic framework material.

[0021] Preferably, when the multi-color luminescent hydrogen bond-organic framework material is pressurized to 0.24 Gpa, the multi-color luminescent hydrogen bond-organic framework material exhibits cyan luminescence with a central wavelength of 483 nm; when the multi-color luminescent hydrogen bond-organic framework material is pressurized to 1.80 Gpa, the multi-color luminescent hydrogen bond-organic framework material exhibits green luminescence with a central wavelength of 523 nm; when the multi-color luminescent hydrogen bond-organic framework material is pressurized to 7.49 Gpa, the multi-color luminescent hydrogen bond-organic framework material exhibits red luminescence with a central wavelength of 600 nm.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] (1) The present invention realizes the construction of a new hydrogen bond-organic framework material by introducing solvent molecules. The introduction of solvent provides abundant hydrogen bonds, thereby improving the rigidity of the framework and changing the conformation of organic molecules, inhibiting their non-radiative energy loss, and greatly improving the luminescence quantum yield of the hydrogen bond-organic framework material, with a maximum luminescence quantum yield of 100%.

[0024] (2) The multi-color luminescent hydrogen bond-organic framework material of the present invention can achieve luminescence color tuning through pressure treatment engineering. The method is simple and environmentally friendly, and the luminescence tuning is highly repeatable, which opens up new application prospects for multi-color luminescent hydrogen bond-organic framework materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a crystal structure diagram of the hydrogen bond-organic framework material HOF-1 provided in Example 1 of the present invention.

[0026] Figure 2 This is the fluorescence spectrum of the hydrogen bond-organic framework material HOF-1 provided in Example 1 of the present invention under 350nm excitation light and normal pressure.

[0027] Figure 3 This is a fluorescence spectrum diagram of the hydrogen bond-organic framework material HOF-1 provided in Example 1 of the present invention when pressure is applied and released.

[0028] Figure 4 This is a CIE chromaticity diagram and fluorescence micrograph of the hydrogen bond-organic framework material HOF-1 provided in Example 1 of the present invention during the pressurization process.

[0029] Figure 5 This is the fluorescence spectrum of the hydrogen bond-organic framework material HOF-2 provided in Example 2 of the present invention under 350nm excitation light and normal pressure.

[0030] Figure 6 This is the fluorescence spectrum of the hydrogen bond-organic framework material HOF-3 provided in Example 3 of the present invention under 350nm excitation light and normal pressure. DETAILED DESCRIPTION

[0031] Example 1

[0032] A multicolor luminescent hydrogen bond-organic framework material, the chemical formula of which is [(L) x (G) y (R) z ], wherein L is tetrakis[4-(3,5-dicarboxyphenyl)]tetraphenylethylene, G is N,N-diethylformamide, R is methanol, x=0.5, y=1, z=1.

[0033] The preparation method of the multi-color luminescent hydrogen bond-organic framework material is as follows: in a small bottle, the organic ligand tetrakis[4-(3,5-dicarboxyphenyl)]tetraphenylethylene (10 mg, 0.01 mmol) is ultrasonically dissolved in 1 mL of a good solvent, N,N-diethylformamide, and then 5 mL of a poor solvent, methanol, is added to the small bottle. The mixture is allowed to stand for 7 days to precipitate a rectangular crystalline hydrogen bond-organic framework material, which is then vacuum-dried at room temperature. The crystal structure thereof is analyzed by single crystal X-ray diffractometry and is designated as HOF-1. Figure 1 shown.

[0034] Fluorescence performance tests show that the hydrogen bond-organic framework material exhibits green light emission with a maximum luminescence wavelength of 500nm under 350nm excitation, and the fluorescence quantum yield reaches 100%. Figure 2 shown.

[0035] T301 stainless steel was used as a sealing metal gasket. First, a diamond anvil press with an anvil diameter of 400um was used to pre-press it to a thickness of 42-45um. Then, a hole with a diameter of 150um was drilled in the center of the pre-pressed position with a drill bit as a pressure cavity. A hydrogen bond-organic framework sample with a diameter of 50-100um and a standard pressure ruby were placed in the pressure cavity together. Silicone oil with a viscosity coefficient of 10cst was used as the pressure transmission medium for cavity packaging. The pressure was increased from room temperature to 10GPa. During the pressurization process, in-situ optical performance tests were carried out simultaneously. A 355nm laser was used as the excitation light source, and the sample fluorescence signal was collected using an Ocean Optics QEPro spectrometer. The results are shown in Figure 2. Figure 3 As shown, as the pressure increases, the fluorescence intensity of the hydrogen-bonded-organic framework material gradually decreases, accompanied by a red shift of the fluorescence peak, with the red shift wavelength exceeding 115nm. When the pressure is released, the fluorescence peak of the material blue-shifts back to its initial state. When the pressure is 0.24GPa, the hydrogen-bonded-organic framework material exhibits cyan luminescence with a central wavelength of 483nm; when the pressure is 1.80GPa, the hydrogen-bonded-organic framework material exhibits green luminescence with a central wavelength of 523nm; and when the pressure is 7.49GPa, the hydrogen-bonded-organic framework material exhibits red luminescence with a central wavelength of 600nm. Figure 4 The CIE chromaticity diagram and in-situ high-pressure fluorescence photographs of the crystal also show that the hydrogen bond-organic framework material has obvious multicolor luminescence characteristics under pressure engineering processing conditions.

[0036] Example 2

[0037] A multicolor luminescent hydrogen bond-organic framework material, the chemical formula of which is [(L) x (G) y (R) z ], wherein L is tetrakis[4-(3,5-dicarboxyphenyl)]tetraphenylethylene, G is N,N-dimethylformamide, R is tetrahydrofuran, x=1, y=4, z=2.

[0038] The preparation method of the multi-color luminescent hydrogen bond-organic framework material is as follows: in a small bottle, the organic ligand tetrakis[4-(3,5-dicarboxyphenyl)]tetraphenylethylene (10 mg, 0.01 mmol) is ultrasonically dissolved in 1 mL of the good solvent N,N-dimethylformamide, and then 10 mL of the poor solvent tetrahydrofuran is added to the small bottle. The material is allowed to stand for 15 days to precipitate a rectangular crystalline hydrogen bond-organic framework material, which is then vacuum-dried at room temperature and recorded as HOF-2.

[0039] Fluorescence performance tests show that the hydrogen bond-organic framework material exhibits blue light emission with a maximum wavelength of 445nm under 350nm excitation, and the fluorescence quantum yield reaches 40%. Figure 5This material is mainly composed of hydrogen bonds between organic ligands. Due to the large size of the ligands, it is difficult to form stable multiple hydrogen bonds. Therefore, it is not as good as the rigid hydrogen bond-organic framework structure in Example 1, which uses solvent molecules to fix the organic ligands through hydrogen bonds to obtain a stable luminescence quantum yield and higher yield.

[0040] Example 3

[0041] A multicolor luminescent hydrogen bond-organic framework material, the chemical formula of which is [(L) x (G) y (R) z ], wherein L is tetrakis[4-(3,5-dicarboxyphenyl)]tetraphenylethylene, G is N,N-dimethylacetamide, R is acetone, x=0.5, y=2, z=2.

[0042] The preparation method of the multi-color luminescent hydrogen bond-organic framework material is as follows: in a small bottle, the organic ligand tetrakis[4-(3,5-dicarboxyphenyl)]tetraphenylethylene (10 mg, 0.01 mmol) is ultrasonically dissolved in 5 mL of the good solvent N,N-dimethylacetamide, and then 25 mL of the poor solvent acetone is added to the small bottle. The material is allowed to stand for 15 days to precipitate a rectangular crystalline hydrogen bond-organic framework material, which is then vacuum-dried at room temperature and recorded as HOF-3.

[0043] Fluorescence performance tests show that the hydrogen bond-organic framework material exhibits blue-green light emission with a maximum luminescence wavelength of 480nm under 350nm excitation, and the fluorescence quantum yield reaches 71%. Figure 6 shown.

[0044] Example 4

[0045] A multicolor luminescent hydrogen bond-organic framework material, the chemical formula of which is [(L) x (G) y (R) z ], wherein L is tetrakis[4-(3,5-dicarboxyphenyl)]tetraphenylethylene, G is N,N-dimethylformamide, R is ethanol, x=1, y=4, z=2.

[0046] The preparation method of the multi-color luminescent hydrogen bond-organic framework material is as follows: in a small bottle, the organic ligand tetrakis[4-(3,5-dicarboxyphenyl)]tetraphenylethylene (10 mg, 0.01 mmol) is ultrasonically dissolved in 1 mL of the good solvent N,N-dimethylformamide, and then 10 mL of the poor solvent ethanol is added to the small bottle. The material is allowed to stand for 15 days to precipitate a rectangular crystalline hydrogen bond-organic framework material, which is then vacuum-dried at room temperature and recorded as HOF-4.

[0047] Example 5

[0048] A multicolor luminescent hydrogen bond-organic framework material, the chemical formula of which is [(L)x (G) y (R) z ], wherein L is tetrakis[4-(3,5-dicarboxyphenyl)]tetraphenylethylene, G is N,N-dimethylacetamide, R is dichloromethane, x=0.5, y=2, z=2.

[0049] The preparation method of the multi-color luminescent hydrogen bond-organic framework material is as follows: in a small bottle, the organic ligand tetrakis[4-(3,5-dicarboxyphenyl)]tetraphenylethylene (10 mg, 0.01 mmol) is ultrasonically dissolved in 5 mL of the good solvent N,N-dimethylacetamide, and then 25 mL of the poor solvent dichloromethane is added to the small bottle. The material is allowed to stand for 15 days to precipitate a rectangular crystalline hydrogen bond-organic framework material, which is then vacuum-dried at room temperature and recorded as HOF-5.

[0050] Example 6

[0051] A multicolor luminescent hydrogen bond-organic framework material, the chemical formula of which is [(L) x (G) y (R) z ], wherein L is tetrakis[4-(3,5-dicarboxyphenyl)]tetraphenylethylene, G is N,N-dimethylacetamide, R is dimethyl sulfoxide, x=0.5, y=2, z=2.

[0052] The preparation method of the multi-color luminescent hydrogen bond-organic framework material is as follows: in a small bottle, the organic ligand tetrakis[4-(3,5-dicarboxyphenyl)]tetraphenylethylene (10 mg, 0.01 mmol) is ultrasonically dissolved in 5 mL of the good solvent N,N-dimethylacetamide, and then 25 mL of the poor solvent dimethyl sulfoxide is added to the small bottle. The material is allowed to stand for 15 days to precipitate a rectangular crystalline hydrogen bond-organic framework material, which is then vacuum-dried at room temperature and recorded as HOF-6.

Claims

1. A multicolor luminescent hydrogen bond-organic framework material, characterized in that: The organic ligand and the organic solvent molecules are connected by hydrogen bonds, and the chemical formula of the multi-color luminescent hydrogen bond-organic framework material is [(L) x (G) y (R) z ], wherein L is tetrakis[4-(3,5-dicarboxyphenyl)]tetraphenylethylene, G represents a good solvent, R represents a poor solvent; x=0.5~1, y=1~4, z=1~2.

2. The multicolor luminescent hydrogen bond-organic framework material according to claim 1, characterized in that: x=0.5, y=1, z=1.

3. The multicolor luminescent hydrogen bond-organic framework material according to claim 1, characterized in that: The good solvent is one of N,N-dimethylformamide, N,N-dimethylacetamide and N,N-diethylformamide.

4. The multicolor luminescent hydrogen bond-organic framework material according to claim 1, characterized in that The poor solvent is one of methanol, acetone, tetrahydrofuran, ethanol, dimethyl sulfoxide and dichloromethane.

5. The method for preparing the multicolor luminescent hydrogen bond-organic framework material according to any one of claims 1 to 4, characterized in that: The following steps are involved: The organic ligand L is dissolved in a good solvent G, and then a poor solvent R is added, and the mixture is allowed to stand for precipitation to obtain the multi-color luminescent hydrogen bond-organic framework material.

6. The method for preparing the multicolor luminescent hydrogen bond-organic framework material according to claim 5, characterized in that: The volume ratio of the good solvent G to the poor solvent R is 1:5-10.

7. The method for preparing the multicolor luminescent hydrogen bond-organic framework material according to claim 5, characterized in that: The concentration of the organic ligand L in the good solvent G is 2-10 mmol / L.

8. The method for preparing the multicolor luminescent hydrogen bond-organic framework material according to claim 5, characterized in that: The standing time is 7 to 15 days.

9. A method for tuning the fluorescence emission color of the multicolor luminescent hydrogen bond-organic framework material according to any one of claims 1 to 4, characterized in that: The multicolor luminescent hydrogen bond-organic framework material is used as an initial material, and the initial material is pressurized by a diamond anvil cell press, thereby changing the fluorescence emission color of the multicolor luminescent hydrogen bond-organic framework material.

10. The method according to claim 9, characterized in that When the multi-color luminescent hydrogen bond-organic framework material is pressurized to 0.24 Gpa, the multi-color luminescent hydrogen bond-organic framework material exhibits cyan luminescence; when the multi-color luminescent hydrogen bond-organic framework material is pressurized to 1.80 Gpa, the multi-color luminescent hydrogen bond-organic framework material exhibits green luminescence; when the multi-color luminescent hydrogen bond-organic framework material is pressurized to 7.49 Gpa, the multi-color luminescent hydrogen bond-organic framework material exhibits red luminescence.

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