Zinc-based coordination polymer room-temperature phosphorescent material, and preparation method and application thereof

Abstract

The application belongs to the field of nanometer luminescent material preparation, and discloses a zinc-based coordination polymer room-temperature phosphorescent material, a preparation method and application thereof. 2,3-pyridinedicarboxylic acid is selected as an organic ligand, combined with metal ions, and a zinc-based coordination polymer room-temperature phosphorescent material is prepared through a solvothermal method. The preparation method is simple, easy to operate, low in risk and green and environment-friendly. The zinc-based coordination polymer room-temperature phosphorescent material has the advantages of nanometer size, longer phosphorescent lifetime and no crystal dependency; after external excitation stops, the visible light emission phenomenon can last more than 2 seconds, and the zinc-based coordination polymer room-temperature phosphorescent material can be widely applied to sensing detection, anti-counterfeiting safety, photoelectric application and biological imaging.

Description

Technical Field

[0001] This invention belongs to the field of nanoluminescent material preparation, specifically relating to a zinc-based coordination polymer room temperature phosphorescent material, its preparation method, and its application. Background Technology

[0002] Phosphorescence can be further divided into low-temperature phosphorescence and room-temperature phosphorescence (RTP) based on its activation temperature. Traditional phosphorescent materials' triplet excited states are easily deactivated at room temperature via non-radiative transitions, thus phosphorescent signals can only be collected at low temperatures; this is called low-temperature phosphorescence. Compared to low-temperature phosphorescent materials, RTP materials can generate phosphorescence at room temperature. From an operational and cost perspective, RTP materials have broader application value in fields such as sensing and detection, anti-counterfeiting and security, optoelectronic applications, bioimaging, and botany.

[0003] Organometallic coordination polymers (CPs) are an interesting class of hybrid materials, forming an infinite network structure extended from inorganic metal ions (or clusters) and organic ligands through coordination interactions. Currently reported room-temperature phosphorescent materials using pyridine-based carboxylic acids as organic ligands suffer from drawbacks such as large particle size, short phosphorescence lifetime, complex ligand structures, and crystal dependence, hindering their further applications. Therefore, developing room-temperature phosphorescent coordination polymer materials with unique emission capabilities, high customizability, and simple synthetic routes has become a key research focus in the field of room-temperature phosphorescence. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a zinc-based coordination polymer room temperature phosphorescent material, its preparation method, and its application. Specifically, the following technical solution is adopted: According to a first aspect of the present invention, a method for preparing a zinc-based coordination polymer room-temperature phosphorescent material is provided, comprising the following steps: 2,3-pyridinedicarboxylic acid and zinc acetate dihydrate were dissolved in N,N-dimethylformamide, mixed thoroughly, and heated for 4-20 h. After the reaction was completed, the mixture was centrifuged, washed, and dried to obtain a zinc-based coordination polymer room temperature phosphorescent material.

[0005] This invention uses 2,3-pyridinedicarboxylic acid as an organic ligand to bind with metal ions, and prepares zinc-based coordination polymer room-temperature phosphorescent materials via a solvothermal method. The preparation method employed in this invention is simple, low-risk, and environmentally friendly, and can be widely applied in industrial production, providing a new approach and method for developing room-temperature phosphorescent materials using pyridine carboxylic acids as organic ligands.

[0006] Preferably, the heating time is 12 h. When the heating time is 12 h, the obtained zinc-based coordination polymer room temperature phosphorescent material has small particle size, long phosphorescence lifetime, and optimal luminescence performance.

[0007] Preferably, the ratio of 2,3-pyridinedicarboxylic acid, zinc acetate dihydrate, and N,N-dimethylformamide is 0.083 g: 0.109 g: 20 mL. When this ratio is used in the reaction, the resulting product exhibits optimal afterglow properties.

[0008] Preferably, triethylamine is added before heating to adjust the pH of the solution to 6.5. A pH of 6.5 facilitates the deprotonation of the carboxyl group on the ligand's carboxylic acid, making it easier for metal ions to bind to the ligand. More preferably, the concentration of triethylamine is 99.5%.

[0009] Preferably, the heating temperature is 90℃-170℃. When the heating temperature is below 90℃, the reaction conditions are too mild, which is not conducive to the formation of afterglow characteristics; when the heating temperature is above 170℃, the temperature is too high, and 2,3-pyridinedicarboxylic acid is easily decomposed. More preferably, the heating temperature is 130℃. When the heating temperature is 130℃, the obtained zinc-based coordination polymer room temperature phosphorescent material has a small particle size, a long phosphorescence lifetime, and the best luminescence performance.

[0010] According to a second aspect of the present invention, a zinc-based coordination polymer room-temperature phosphorescent material is also provided, prepared by the above-described method, having an average particle size of 180 nm. Compared to other room-temperature phosphorescent coordination polymers constructed from pyridine carboxylic acid ligands, the zinc-based coordination polymer room-temperature phosphorescent material prepared by the present invention has advantages such as nanoscale size, longer phosphorescence lifetime, and no crystal dependence. Furthermore, the material exhibits two emission peaks in its instantaneous spectrum at 410 nm and 478 nm, and one emission peak in its delayed spectrum at 505 nm; the optimal excitation wavelength is 360 nm, and a green afterglow of more than 2 s can be observed after the ultraviolet lamp is turned off.

[0011] According to a third aspect of the present invention, the above-mentioned zinc-based coordination polymer room temperature phosphorescent material is also provided for applications in sensing and detection, anti-counterfeiting and security, optoelectronic applications, and bioimaging.

[0012] The beneficial effects of this invention are as follows: This invention uses 2,3-pyridinedicarboxylic acid as an organic ligand, which combines with metal ions to prepare zinc-based coordination polymer room-temperature phosphorescent materials via a solvothermal method. The preparation method used in this invention is simple, easy to implement, low-risk, and environmentally friendly. The zinc-based coordination polymer room-temperature phosphorescent material prepared by this invention has advantages such as nanoscale size, longer phosphorescence lifetime, and no crystal dependence; after external excitation stops, the visible luminescence phenomenon lasts for more than 2 seconds, and it can be widely used in sensing detection, anti-counterfeiting security, optoelectronic applications, and bioimaging. Attached Figure Description

[0013] Figure 1 The image shown is a SEM image of the zinc-based coordination polymer room-temperature phosphorescent material prepared in Example 1. Figure 2 The image shows the excitation spectrum of the zinc-based coordination polymer room-temperature phosphorescent material prepared in Example 1; Figure 3 The image shows the instantaneous spectrum of the zinc-based coordination polymer room-temperature phosphorescent material prepared in Example 1; Figure 4 The image shows the delayed spectrum of the zinc-based coordination polymer room-temperature phosphorescent material prepared in Example 1; Figure 5 The image shows the time-resolved spectrum of the zinc-based coordination polymer room-temperature phosphorescent material prepared in Example 1; Figure 6 The images shown are afterglow photographs of the zinc-based coordination polymer room-temperature phosphorescent materials prepared in Examples 1-5 at different reaction temperatures; Figure 7 The images shown are afterglow photographs of the zinc-based coordination polymer room-temperature phosphorescent materials prepared in Examples 1 and 6-9 at different reaction times. Detailed Implementation

[0014] The following will provide a clear and complete description of the concept and technical effects of the present invention in conjunction with the embodiments and accompanying drawings, so as to fully understand the purpose, solution and effects of the present invention. It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of this application can be combined with each other.

[0015] Example 1 A zinc-based coordination polymer room-temperature phosphorescent material, the preparation method of which includes the following steps: First, 0.083 g of 2,3-pyridinedicarboxylic acid was dissolved in 20 mL of N,N-dimethylformamide. Then, 0.109 g of zinc acetate dihydrate was added to the solution and stirred for 10 min. Triethylamine was then added to adjust the pH of the solution to 6.5, and the mixture was stirred for another 10 min. The solution was then transferred to a reaction vessel and reacted in a forced-air drying oven at 130 °C for 12 h. After centrifuging the precipitate, it was washed three times with N,N-dimethylformamide and dried in a vacuum drying oven at 60 °C for 24 h to obtain the zinc-based coordination polymer room-temperature phosphorescent material.

[0016] The morphology and optical properties of the sample were then characterized, and the results are as follows: Figure 1-5 As shown.

[0017] like Figure 1 The image shown is a SEM image of the prepared zinc-based coordination polymer room temperature phosphorescent material, which shows that its average particle size is 180 nm.

[0018] like Figure 2 The figure shows the excitation spectrum of the prepared zinc-based coordination polymer room temperature phosphorescent material. As can be seen from the figure, the optimal excitation wavelength is 360 nm.

[0019] like Figure 3 The figure shows the instantaneous spectrum of the prepared zinc-based coordination polymer room temperature phosphorescent material. As can be seen from the figure, there are two emission peaks at 410 nm and 478 nm.

[0020] like Figure 4 The figure shows the delayed spectrum of the prepared zinc-based coordination polymer room temperature phosphorescent material. As can be seen from the figure, the maximum phosphorescence emission wavelength is 505 nm.

[0021] like Figure 5 The image shows the time-resolved spectrum of the prepared zinc-based coordination polymer room-temperature phosphorescent material, with an emission lifetime of approximately 0.8 s. The upper right corner shows photographs of the material under a UV lamp and with the UV lamp off. It can be seen that the material's fluorescence color is blue, and its phosphorescence color is green.

[0022] Example 2 A zinc-based coordination polymer room-temperature phosphorescent material is prepared by a method that differs from the temperature adjustment of the drying oven in Example 1 by changing it to 90 °C. The specific steps include: First, 0.083 g of 2,3-pyridinedicarboxylic acid was dissolved in 20 mL of N,N-dimethylformamide. Then, 0.109 g of zinc acetate dihydrate was added to the solution and stirred for 10 min. Triethylamine was then added to adjust the pH of the solution to 6.5, and the mixture was stirred for another 10 min. The solution was then transferred to a reaction vessel and reacted in a forced-air drying oven at 90 °C for 12 h. After centrifuging the precipitate, it was washed three times with N,N-dimethylformamide and dried in a vacuum drying oven at 60 °C for 24 h to obtain the zinc-based coordination polymer room-temperature phosphorescent material.

[0023] Example 3 A zinc-based coordination polymer room-temperature phosphorescent material is prepared by modifying the temperature of the drying oven in Example 1 to 110 °C, and specifically includes the following steps: First, 0.083 g of 2,3-pyridinedicarboxylic acid was dissolved in 20 mL of N,N-dimethylformamide. Then, 0.109 g of zinc acetate dihydrate was added to the solution and stirred for 10 min. Triethylamine was then added to adjust the pH of the solution to 6.5, and the mixture was stirred for another 10 min. The solution was then transferred to a reaction vessel and reacted in a forced-air drying oven at 110 °C for 12 h. After centrifuging the precipitate, it was washed three times with N,N-dimethylformamide and dried in a vacuum drying oven at 60 °C for 24 h to obtain the zinc-based coordination polymer room-temperature phosphorescent material.

[0024] Example 4 A zinc-based coordination polymer room-temperature phosphorescent material is prepared by modifying the temperature of the drying oven in Example 1 to 150 °C, and specifically includes the following steps: First, 0.083 g of 2,3-pyridinedicarboxylic acid was dissolved in 20 mL of N,N-dimethylformamide. Then, 0.109 g of zinc acetate dihydrate was added to the solution and stirred for 10 min. Triethylamine was then added to adjust the pH of the solution to 6.5, and the mixture was stirred for another 10 min. The solution was then transferred to a reaction vessel and reacted in a forced-air drying oven at 150 °C for 12 h. After centrifuging the precipitate, it was washed three times with N,N-dimethylformamide and dried in a vacuum drying oven at 60 °C for 24 h to obtain the zinc-based coordination polymer room-temperature phosphorescent material.

[0025] Example 5 A zinc-based coordination polymer room-temperature phosphorescent material is prepared by modifying the temperature of the drying oven in Example 1 to 170 °C, and specifically includes the following steps: First, 0.083 g of 2,3-pyridinedicarboxylic acid was dissolved in 20 mL of N,N-dimethylformamide. Then, 0.109 g of zinc acetate dihydrate was added to the solution and stirred for 10 min. Triethylamine was then added to adjust the pH of the solution to 6.5, and the mixture was stirred again for 10 min. The solution was then transferred to a reaction vessel and reacted in a forced-air drying oven at 170 °C for 12 h. After centrifuging the precipitate, it was washed three times with N,N-dimethylformamide and dried in a vacuum drying oven at 60 °C for 24 h to obtain the zinc-based coordination polymer room-temperature phosphorescent material.

[0026] like Figure 6 The image shows afterglow photographs of the zinc-based coordination polymer room-temperature phosphorescent materials prepared in Examples 1-5. As can be seen from the image, the material exhibits the best luminescence performance when the reaction temperature is 130 °C.

[0027] Example 6 A zinc-based coordination polymer room-temperature phosphorescent material is prepared by modifying the drying oven setting time in Example 1 to 4 hours, and specifically includes the following steps: First, 0.083 g of 2,3-pyridinedicarboxylic acid was dissolved in 20 mL of N,N-dimethylformamide. Then, 0.109 g of zinc acetate dihydrate was added to the solution and stirred for 10 min. Triethylamine was then added to adjust the pH of the solution to 6.5, and the mixture was stirred for another 10 min. The solution was then transferred to a reaction vessel and reacted in a forced-air drying oven at 130 °C for 4 h. After centrifuging the precipitate, it was washed three times with N,N-dimethylformamide and dried in a vacuum drying oven at 60 °C for 24 h to obtain the zinc-based coordination polymer room-temperature phosphorescent material.

[0028] Example 7 A zinc-based coordination polymer room-temperature phosphorescent material is prepared by modifying the drying oven setting time in Example 1 to 8 hours, and specifically includes the following steps: First, 0.083 g of 2,3-pyridinedicarboxylic acid was dissolved in 20 mL of N,N-dimethylformamide. Then, 0.109 g of zinc acetate dihydrate was added to the solution and stirred for 10 min. Triethylamine was then added to adjust the pH of the solution to 6.5, and the mixture was stirred for another 10 min. The solution was then transferred to a reaction vessel and reacted in a forced-air drying oven at 130 °C for 8 h. After centrifuging the precipitate, it was washed three times with N,N-dimethylformamide and dried in a vacuum drying oven at 60 °C for 24 h to obtain the zinc-based coordination polymer room-temperature phosphorescent material.

[0029] Example 8 A zinc-based coordination polymer room-temperature phosphorescent material is prepared by modifying the drying oven setting time in Example 1 to 16 hours, and specifically includes the following steps: First, 0.083 g of 2,3-pyridinedicarboxylic acid was dissolved in 20 mL of N,N-dimethylformamide. Then, 0.109 g of zinc acetate dihydrate was added to the solution and stirred for 10 min. Triethylamine was then added to adjust the pH of the solution to 6.5, and the mixture was stirred for another 10 min. The solution was then transferred to a reaction vessel and reacted in a forced-air drying oven at 130 °C for 16 h. After centrifuging the precipitate, it was washed three times with N,N-dimethylformamide and dried in a vacuum drying oven at 60 °C for 24 h to obtain the zinc-based coordination polymer room-temperature phosphorescent material.

[0030] Example 9 A zinc-based coordination polymer room-temperature phosphorescent material is prepared by modifying the drying oven setting time in Example 1 to 20 hours. The specific steps include: First, 0.083 g of 2,3-pyridinedicarboxylic acid was dissolved in 20 mL of N,N-dimethylformamide. Then, 0.109 g of zinc acetate dihydrate was added to the solution and stirred for 10 min. Triethylamine was then added to adjust the pH of the solution to 6.5, and the mixture was stirred for another 10 min. The solution was then transferred to a reaction vessel and reacted in a forced-air drying oven at 130 °C for 20 h. After centrifuging the precipitate, it was washed three times with N,N-dimethylformamide and dried in a vacuum drying oven at 60 °C for 24 h to obtain the zinc-based coordination polymer room-temperature phosphorescent material.

[0031] like Figure 7 The image shows afterglow photographs of the zinc-based coordination polymer room-temperature phosphorescent materials prepared in Examples 1 and 6-9. As can be seen from the figure, the material exhibits the best luminescence performance when the reaction time is 12 h.

[0032] Although the description of the invention has been quite detailed and particularly of several described embodiments, it is not intended to limit it to any of these details or embodiments or any particular embodiment, but should be considered as providing a broad possible interpretation of the claims by referring to the appended claims and taking into account the prior art, thereby effectively covering the intended scope of the invention. Furthermore, the invention has been described above with respect to embodiments foreseeable by the inventors in order to provide a useful description, and non-substantial modifications to the invention that have not yet been foreseen may still represent equivalent modifications.

Claims

1. A method for preparing a zinc-based coordination polymer room-temperature phosphorescent material, characterized in that, Includes the following steps: 2,3-pyridinedicarboxylic acid and zinc acetate dihydrate were dissolved in N,N-dimethylformamide, mixed thoroughly, and heated for 12 h. After the reaction was completed, the mixture was centrifuged, washed, and dried to obtain a zinc-based coordination polymer room temperature phosphorescent material. The heating temperature is 130°C; The ratio of the 2,3-pyridine dicarboxylic acid, the zinc acetate dihydrate, and the N,N-dimethylformamide is 0.083 g: 0.109 g: 20 mL; Before heating, triethylamine needs to be added to adjust the pH of the solution to 6.

5.

2. The preparation method according to claim 1, characterized in that, The concentration of the triethylamine is 99.5%.

3. A zinc-based coordination polymer room-temperature phosphorescent material, characterized in that, It is prepared by the preparation method according to any one of claims 1-2.

4. The zinc-based coordination polymer room-temperature phosphorescent material according to claim 3, characterized in that, The zinc-based coordination polymer room-temperature phosphorescent material has an average particle size of 180 nm.

5. The application of the zinc-based coordination polymer room-temperature phosphorescent material according to claim 3 in sensing and detection, anti-counterfeiting and security, optoelectronic applications, and bioimaging.

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