Pyrazolyl gallium oxide clusters with blue light performance, their preparation methods and uses
Synthesis of pyrazolyl gallium oxide clusters through solvent thermal reactions solved the problem of insufficient blue light components in white LEDs, and efficient blue fluorescent materials were prepared for fluorescent light-emitting devices and anti-counterfeiting labels, which improved the color rendering and application potential of LEDs.
Patent Information
- Application Number
- CN202211232698.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2022-10-10
- Publication Date
- 2025-07-29
- Estimated Expiration
- 2042-10-10
AI Technical Summary
The lack of blue light components in existing white LEDs leads to poor color rendering and high color temperature, and insufficient research on blue light phosphors, limiting the application potential of LEDs.
The pyrazolyl ligand, 2-fluorobenzoic acid and gallium chloride were used as raw materials to synthesize pyrazolyl gallium oxide clusters with blue light properties through solvothermal reactions. The electron conjugation system of the pyrazolyl ligand and the coordination ability of nitrogen atoms were used to form a cluster with strong fluorescence properties.
A blue-ray fluorescent material with excellent fluorescent quantum yield was prepared, which is suitable for the luminescent layer and anti-counterfeiting label of fluorescent light-emitting devices, which solves the problem of insufficient blue-ray components and improves the color rendering and luminous efficiency of LEDs.
Smart Images
Figure CN115504997B_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the technical field of preparation of fluorescent materials, and particularly relates to a pyrazolyl gallium oxide cluster with blue light performance, a preparation method thereof and uses thereof. Background Art
[0002] With the development of lighting technology, the research on LEDs has become more and more mature. At present, there are mainly two methods to obtain white LEDs: one is that a blue LED chip directly excites a yellow phosphor, and the light emitted by the two is mixed to form white light. This method is currently the most mature, but the white light obtained in this way lacks the red part, which will lead to poor color rendering of the emitted light and a relatively high color temperature. The other is that under the excitation of near-ultraviolet or ultraviolet light, the light emitted by three kinds of phosphors (red, blue, green) is mixed together to form white light. The white LEDs prepared by this excitation method have the advantages of high color rendering, high luminous efficiency, energy conservation and environmental protection, and can be applied to display, lighting and other aspects. The blue phosphors under near-ultraviolet light excitation are relatively few, and most of the phosphor technologies stay in the medium and long wavelength (green light, red light) emission bands. Due to the lack of the short wavelength blue light band, the overall application of LEDs still appears to be somewhat insufficient. Secondly, the main component of the blue LED chip, namely the blue light diode, also requires a blue phosphor for its light-emitting layer.
[0003] In summary, there is an urgent need to develop a phosphor with blue light performance at short wavelengths, which will have great market prospects and application values in the fields of photoluminescence and electroluminescence. Summary of the Invention
[0004] One of the purposes of the present invention is to provide a preparation method of a pyrazolyl gallium oxide cluster with blue light performance at short wavelengths.
[0005] To achieve the above purpose, the present invention adopts the following technical solutions: A preparation method of a pyrazolyl gallium oxide cluster with blue light performance, comprising the following steps:
[0006] S1. Weigh 2-fluorobenzoic acid and a pyrazolyl ligand and dissolve them in a solvent to obtain a mixed solution; weigh gallium chloride and mix it with the above mixed solution, and discharge the hydrogen chloride gas generated by the hydrolysis of gallium chloride to obtain a miscible mixture;
[0007] S2. Ultrasonically dissolve the miscible mixture in step S1 under a water bath condition, and then carry out a solvothermal reaction at 100-120 °C;
[0008] S3. After the reaction is completed, take out the miscible mixture and cool it, and place it at room temperature to wait for the solvent to slowly volatilize, and then pyrazolyl gallium oxide clusters with blue light performance can be precipitated.
[0009] As a further improvement of the preparation method of the pyrazolyl gallium oxide cluster with blue light performance:
[0010] Preferably, the solvent in step S1 is N,N-dimethylformamide.
[0011] Preferably, in step S1, gallium chloride is weighed in a glove box under inert gas protection.
[0012] Preferably, the inert gas is nitrogen.
[0013] Preferably, the pyrazolyl ligand in step S1 is pyrazole or 4-methylpyrazole.
[0014] Preferably, the molar mass ratio of gallium chloride, 2-fluorobenzoic acid, and pyrazolyl ligand in step S1 is 1:(1-2):(3.1-13.3).
[0015] Preferably, in step S2, the temperature of the water bath condition is 20-25 °C, and ultrasonic dissolution is carried out for 20-30 min under the water bath condition.
[0016] Preferably, the time of the solvothermal reaction in step S2 is 72-84 h.
[0017] The second object of the present invention is to provide a pyrazolyl gallium oxide cluster with blue light performance prepared by the preparation method of any one of the above.
[0018] The third object of the present invention is to provide the use of the above-mentioned pyrazolyl gallium oxide cluster with blue light performance in a fluorescent light-emitting device.
[0019] The beneficial effects of the present invention compared with the prior art are as follows:
[0020] 1) The present invention uses a pyrazolyl ligand, 2-fluorobenzoic acid, and gallium chloride as raw materials. By studying the synthesis and luminescence properties of pyrazolyl ligand clusters, a fluorescent light-emitting compound with excellent fluorescence quantum yield is prepared by a solvothermal reaction synthesis method. The pyrazolyl ligand (pyrazole, 4-methylpyrazole) has a pyrazole five-membered ring, contains an electron conjugate system and strong π-π* absorption transitions, and has the possibility of emitting strong fluorescence. At the same time, the nitrogen atom of the pyrazolyl ligand has rich and diverse coordination abilities, and can form metal clusters with novel structures of different dimensions with metal ions. The fluorine in 2-fluorobenzoic acid and the nitrogen in the pyrazolyl ligand have strong electron-withdrawing abilities, and can form hydrogen bonds or generate π-π stacking / C-H...π interactions between clusters. On the one hand, this promotes the aggregation and crystallization of clusters, and on the other hand, it enhances the charge transfer between clusters and ligands, thereby affecting the luminescence intensity or fluorescence performance. The blue fluorescence luminescence intensity of the clusters can be improved by adjusting the content of 2-fluorobenzoic acid and the content of the pyrazolyl ligand, and at the same time, it is beneficial to the crystallization of the clusters.
[0021] 2) The preparation method of the present invention provides a rich material basis for the fabrication of light-emitting devices. The solvothermal reaction synthesis method is easy to operate, has sufficient raw material sources, low production costs, and high yields and purities of cluster synthesis, making it suitable for the requirements of large-scale production.
[0022] 3) The components of the target product prepared by the present invention were analyzed by EDS energy spectrum. The main constituent elements of the prepared target product include gallium, carbon, chlorine, nitrogen, and oxygen. The maximum excitation wavelength of the prepared gallium oxide clusters was measured by an Edinburgh FLS-1000 steady-state fluorescence spectrometer to be in the range of 359 - 361 nm, and there was a strong emission in the nearby blue light region of 433 - 436 nm. The absolute quantum yield of the product was 15.01% - 17.70%. The pyrazolyl gallium clusters with blue light properties prepared by the present invention are a new type of fluorescent light-emitting material and can be used for making the light-emitting layer of blue fluorescent light-emitting devices and anti-counterfeiting labels, etc. BRIEF DESCRIPTION OF THE DRAWINGS
[0023] Figure 1 It is the EDS energy spectrum elemental analysis result of the gallium oxide clusters prepared in Example 1.
[0024] Figure 2 It is the fluorescence emission spectrum diagram of the gallium oxide clusters prepared in Example 1.
[0025] Figure 3 It is the fluorescence excitation spectrum diagram of the gallium oxide clusters prepared in Example 1.
[0026] Figure 4 It is the EDS energy spectrum elemental analysis result of the gallium oxide clusters prepared in Example 2.
[0027] Figure 5 It is the fluorescence emission spectrum diagram of the gallium oxide clusters prepared in Example 2.
[0028] Figure 6 It is the fluorescence excitation spectrum diagram of the gallium oxide clusters prepared in Example 2. DETAILED DESCRIPTION OF THE EMBODIMENTS
[0029] In order to make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below in conjunction with embodiments. Based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts fall within the scope of protection of the present invention.
[0030] Example 1
[0031] This example provides a preparation method of pyrazolyl gallium oxide clusters with blue light properties, which specifically includes the following steps:
[0032] S1. Weigh pyrazole (C3H4N2, 2.350 mmol) and 2-fluorobenzoic acid (C7H5FO2, 0.177 mmol). Dissolve and mix them in DMF (N,N-dimethylformamide) to obtain a mixed solution. Weigh gallium chloride (GaCl3, 0.177 mmol) reagent in a glove box under the protection of inert gas nitrogen, put it into a 20 mL disposable scintillation vial, and add the mixed solution. Then, discharge the hydrogen chloride gas generated by the hydrolysis of gallium chloride in the vial to obtain a miscible mixture.
[0033] S2. Ultrasonically dissolve the miscible mixture in step S1 in a 20 °C water bath for 25 min. After drying the moisture on the outer wall of the bottle, put it into an oven preheated to 120 °C, take it out after heating for 72 h, let it stand at room temperature, and slowly volatilize the solvent. After several days, crystals can be precipitated to obtain the target product, namely pyrazolyl gallium oxide cluster.
[0034] The target product prepared in this example was characterized by scanning electron microscopy combined with EDS energy spectrum analysis. The results showed that the main elements of the material were gallium, carbon, chlorine, nitrogen, and oxygen ( Figure 1 ). The product was measured by an Edinburgh FLS-1000 steady-state fluorescence spectrometer and showed blue light emission with a maximum emission wavelength of 436 nm ( Figure 2 ), where the maximum excitation wavelength was 361 nm ( Figure 3 ), and the absolute quantum yield was 16.02%. Using the CIE1931 color coordinate calculation software to calculate the fluorescence emission spectrum data obtained by the test, it was found that the color coordinate of the gallium oxide cluster was (0.17, 0.09), indicating that the luminescence color of the target product was blue.
[0035] Example 2
[0036] This example provides a preparation method of pyrazolyl gallium oxide cluster with blue light performance, which specifically includes the following steps:
[0037] S1. Weigh 4-methylpyrazole (C4H6N2, 1.020 mmol) and 2-fluorobenzoic acid (C7H5FO2, 0.176 mmol). Dissolve and mix them in DMF (N,N-dimethylformamide) to obtain a mixed solution. Weigh gallium chloride (GaCl3, 0.176 mmol) reagent in a glove box under the protection of inert gas nitrogen, put it into a 20 mL disposable scintillation vial, and add the mixed solution. Then, discharge the hydrogen chloride gas generated by the hydrolysis of gallium chloride in the vial to obtain a miscible mixture.
[0038] S2. Ultrasonically dissolve the miscible mixture in step S1 in a 25 °C water bath for 25 min. After drying the moisture on the outer wall of the bottle, put it into an oven preheated to 120 °C, take it out after heating for 72 h, let it stand at room temperature, and slowly volatilize the solvent. After several days, crystals can be precipitated to obtain the target product, namely pyrazolyl gallium oxide cluster.
[0039] The target product obtained in this example was characterized by scanning electron microscopy combined with EDS energy spectrum analysis. The results showed that the main constituent elements of the material were gallium, carbon, oxygen, chlorine, and nitrogen ( Figure 4 ). The product was measured by an Edinburgh FLS-1000 steady-state fluorescence spectrometer and showed blue light emission with a maximum emission wavelength of 433 nm ( Figure 5 ), where the maximum excitation wavelength was 359 nm ( Figure 6 ), and the absolute quantum yield was 17.70%. The fluorescence emission spectrum data obtained from the test was calculated using CIE1931 color coordinate calculation software, and the color coordinates of the gallium oxide cluster were found to be (0.16, 0.09), indicating that the emission color of the target product was blue.
[0040] Example 3
[0041] This example provides a preparation method for pyrazolyl gallium oxide clusters with blue light performance, which specifically includes the following steps:
[0042] S1. Weigh pyrazole (C3H4N2, 2.350 mmol) and 2-fluorobenzoic acid (C7H5FO2, 0.352 mmol), dissolve and mix them in DMF (N,N-dimethylformamide) to obtain a mixed solution; weigh gallium chloride (GaCl3, 0.176 mmol) reagent in a glove box protected by inert gas nitrogen and put it into a 20 mL disposable scintillation vial, then add the mixed solution and expel the hydrogen chloride gas generated by the hydrolysis of gallium chloride in the vial to obtain a miscible mixture;
[0043] S2. Ultrasonically dissolve the miscible mixture in step S1 for 25 min under the condition of a 25 °C water bath. After drying the moisture on the outer wall of the bottle, put it into an oven preheated to 120 °C, take it out after heating for 72 h, let it stand at room temperature, and slowly evaporate the solvent. Crystals can be precipitated after several days to obtain the target product, namely pyrazolyl gallium oxide clusters.
[0044] The product was measured by an Edinburgh FLS-1000 steady-state fluorescence spectrometer and showed blue light emission with a maximum emission wavelength of 436 nm, where the maximum excitation wavelength was 360 nm, and the absolute quantum yield was 15.01%. The fluorescence emission spectrum data obtained from the test was calculated using CIE1931 color coordinate calculation software, and the color coordinates of the gallium oxide cluster were found to be (0.16, 0.10), indicating that the emission color of the target product was blue.
[0045] The test results of the products obtained in the above Examples 1-3 confirmed that the pyrazolyl gallium oxide clusters prepared by the present invention have blue light fluorescence performance with short wavelengths and can be used for making the light-emitting layer of blue fluorescent light-emitting devices and anti-counterfeiting labels, etc.
[0046] Those skilled in the art should understand that the above are only several specific embodiments of the present invention, rather than all embodiments. It should be noted that many modifications and improvements can be made by those of ordinary skill in the art, and all modifications or improvements that do not exceed the scope described in the claims shall be regarded as the protection scope of the present invention.
Claims
1. A preparation method of a pyrazolyl gallium oxide cluster with blue light performance, characterized in that, It includes the following steps: S1. Weigh 2-fluorobenzoic acid and pyrazolyl ligand and dissolve them in a solvent to obtain a mixed solution; weigh gallium chloride and mix it with the above mixed solution, and discharge the hydrogen chloride gas generated by the hydrolysis of gallium chloride to obtain a miscible mixture; the pyrazolyl ligand is pyrazole or 4-methylpyrazole; S2. Ultrasonically dissolve the miscible mixture in step S1 under the condition of a water bath, and then carry out a solvothermal reaction at 100-120 °C; S3. After the reaction is completed, take out the miscible mixture and cool it, and place it at room temperature to wait for the solvent to slowly volatilize, and pyrazolyl gallium oxide clusters with blue light performance can be precipitated.
2. The preparation method of a pyrazolyl gallium oxide cluster having blue light performance according to claim 1, characterized in that, The solvent in step S1 is N,N-dimethylformamide.
3. The preparation method of a pyrazolyl gallium oxide cluster having blue light performance according to claim 1, characterized in that, In step S1, gallium chloride is weighed in a glove box protected by an inert gas, and after being added to a scintillation vial, it is mixed with the mixed solution in the scintillation vial.
4. The preparation method of a pyrazolyl gallium oxide cluster having blue light performance according to claim 3, characterized in that, The inert gas is nitrogen.
5. The preparation method of a pyrazolyl gallium oxide cluster with blue light performance according to claim 1, characterized in that, In step S1, the molar mass ratio of gallium chloride, 2-fluorobenzoic acid, and pyrazolyl ligand is 1:(1-2):(3.1-13.3).
6. The preparation method of a pyrazolyl gallium oxide cluster having blue light performance according to claim 1, characterized in that, In step S2, the temperature of the water bath condition is 20-25 °C, and ultrasonic dissolution is carried out for 20-30 min under the water bath condition.
7. The preparation method of a pyrazolyl gallium oxide cluster having blue light performance according to claim 1, characterized in that, In step S2, the time of the solvothermal reaction is 72-84 h.
8. Pyrazolyl gallium oxide clusters with blue light performance prepared by the preparation method according to any one of claims 1-7.
9. Use of the pyrazolyl gallium oxide clusters with blue light performance according to claim 8 in a fluorescent light-emitting device.
Citation Information
Patent Citations
I-II-III-VI family quantum dots and preparation method thereof
CN102154007A
Organic luminous element
CN103996795A