Organic-inorganic hybrid material with X-ray scintillation performance as well as preparation method and application of organic-inorganic hybrid material

Abstract

The invention provides an organic-inorganic hybrid material with X-ray scintillation performance as well as a preparation method and application of the organic-inorganic hybrid material. The preparation method of the organic-inorganic hybrid material comprises the following steps: fully mixing uranium salt, boric acid (H3BO3), isonicotinic acid and deionized water (H2O), carrying out a heating reaction, and washing and drying a solid product to obtain the organic-inorganic hybrid material with the X-ray scintillation performance. The synthesis method of the material is simple and convenient, mild in reaction condition, low in cost and high in yield. The material provided by the invention can effectively absorb high-energy X-rays and convert the X-rays into visible light, and has the properties of high light output, stable material, strong ray retardation capability and the like. The organic-inorganic hybrid material combines the advantages of organic and inorganic materials, such as structural diversity, tunability and good processability, and provides a new thought for the development of novel scintillation materials.

Description

Technical Field

[0001] The present invention belongs to the technical field of scintillators, and particularly relates to an organic-inorganic hybrid material with X-ray scintillation performance, a preparation method thereof, and applications thereof. Background Art

[0002] A scintillator material is a material that can convert high-energy particles or rays into visible light. X-ray scintillator materials have wide applications in the fields of medical imaging, security inspection, materials science, high-energy physics, etc.

[0003] The development history of scintillator materials can be traced back to the end of the 19th century and the beginning of the 20th century. German physicist Roentgen discovered X-rays and took the first X-ray photograph in human history, making CaWO 4 become the world's first scintillator material. Early inorganic scintillators included crystals such as ZnS, NaI, and CsI. The luminous efficiency of such pure inorganic salt crystals was relatively low. Currently, scintillators are mainly divided into two categories: organic scintillators and inorganic scintillators. Although organic scintillating materials such as anthracene, naphthalene, and pyrene have advantages such as high cost-effectiveness, fast attenuation, and good processability, due to the lack of high atomic number components, their ability to block X-rays is weak, and their light output ability is limited. Inorganic scintillator materials include NaI:Tl, CsI:Tl, Bi 4 Ge 3 O 12 (BGO), etc. Compared with NaI and CsI, after doping with Tl + , the luminous efficiency of NaI:Tl and CsI:Tl is significantly improved. However, such materials are prone to deliquescence, severely limiting their application scope. The BGO material has good stability, a large density of the material itself, and a strong ability to block high-energy rays, meeting the application characteristics of scintillator materials. However, the raw materials of this material are expensive and the preparation process is relatively complex, which increases the production cost and preparation difficulty, and it can only be used in specific fields currently.

[0004] Therefore, finding a scintillator with high light output, material stability, strong ray blocking ability, etc., which has high performance and low price, is still an important content in the development of scintillators. Summary of the Invention

[0005] Aiming at the deficiencies of the existing technology, the present invention provides an organic-inorganic hybrid material with X-ray scintillation performance, a preparation method thereof, and applications thereof. The material synthesis method of the present invention is simple, the reaction conditions are mild, the cost is low, and the yield is high. The material of the present invention can effectively absorb high-energy X-rays and convert them into visible light, and has properties such as high light output, material stability, and strong ray blocking ability. The organic-inorganic hybrid material of the present invention combines the advantages of organic and inorganic materials, such as structural diversity, tunability, and good processability, providing new ideas for the development of new scintillator materials.

[0006] The technical solution of the present invention is as follows:

[0007] A method for preparing an organic-inorganic hybrid material having X-ray scintillation performance comprises the steps of:

[0008] Uranium salt, boric acid (H 3 BO 3 ), isonicotinic acid and deionized water (H 2 O) are fully mixed, heated for reaction, and the solid product is washed and dried to obtain an organic-inorganic hybrid material with X-ray scintillation performance.

[0009] Preferably according to the present invention, the uranium salt is uranyl nitrate hydrate or uranyl acetate hydrate.

[0010] Preferably according to the present invention, the molar ratio of the uranium salt to the boric acid is 1:5-20, preferably 1:10-15, and further preferably 1:15.

[0011] Preferably according to the present invention, the molar ratio of the uranium salt to isonicotinic acid is 1:1-2, preferably 1:1.5.

[0012] Preferably according to the present invention, the volume ratio of the molar amount of the uranium salt to the deionized water is 2-4 mmol / mL.

[0013] Preferably, according to the present invention, the heating reaction temperature is 170-220° C. and the reaction time is 2-4 days.

[0014] An organic-inorganic hybrid material with X-ray scintillation performance is prepared by the above method.

[0015] According to the preferred embodiment of the present invention, the structure of the organic-inorganic hybrid material is shown as follows:

[0016]

[0017] Application of the above organic-inorganic hybrid material with X-ray scintillation performance in X-ray scintillator materials.

[0018] Technical features and beneficial effects of the present invention:

[0019] 1. The present invention provides a new method for synthesizing a uranium-containing hybrid material with X-ray scintillation performance. The material synthesis method is simple, the reaction conditions are mild, high temperature and high pressure and long reaction time are not required, the preparation cost and production difficulty are reduced, and the material is easy to prepare with a yield of up to 70%.

[0020] 2. As a scintillator material, the uranium-containing compound of the present invention has a uranyl luminescence center that is intrinsic luminescence. There is no need to introduce a ligand for energy transfer, and the energy of the excitation source can be directly transferred to the element itself for luminescence. Due to its high atomic number and rich energy level structure, uranium shows significant advantages in X-ray absorption and energy conversion, and has a high X-ray absorption efficiency. The material of the present invention can effectively absorb high-energy X-rays and convert them into visible light, and has advantages such as high light output, material stability, and strong ray blocking ability.

[0021] 3. The organic-inorganic hybrid material synthesized by the method of the present invention combines the advantages of organic materials and inorganic materials, and has structural diversity, controllability, and excellent properties.

[0022] 4. In the method of the present invention, boric acid not only serves as a component of the inorganic ligand in the hybrid material, but also serves as a reaction solvent, providing reaction conditions for the preparation of the hybrid material during the reaction process. Therefore, the reaction temperature is very important during the material preparation process. This preparation process needs to be carried out under the molten condition of boric acid. Therefore, the reaction temperature must be higher than the melting point of boric acid to ensure that the reactants are in a liquid state, thereby promoting the reaction. The melting point of boric acid is about 170 degrees. If the reaction temperature is too low and does not reach the melting point of boric acid, the reaction cannot proceed and the target product cannot be obtained. The raw material ratio is also relatively important during the material preparation process. If the ratio is inappropriate, the resulting product has no response to X-rays, or the yield is extremely low, or the target product cannot be obtained. As a whole, the method of the present invention can achieve the excellent effects of the present invention only when each step and each condition work together. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 Emission spectrum of the organic-inorganic hybrid material obtained in Example 1 under UV irradiation.

[0024] Figure 2 Emission spectrum of the organic-inorganic hybrid material obtained in Example 1 under X-ray irradiation.

[0025] Figure 3 Emission data graph of the organic-inorganic hybrid material obtained in Example 1 under different X-ray intensities.

[0026] Figure 4 Normalized graph of different X-ray intensities and emission intensities of the organic-inorganic hybrid material obtained in Example 1.

[0027] Figure 5 Absorption coefficient graph of the organic-inorganic hybrid material obtained in Example 1 at 30 eV - 30 KeV.

[0028] Figure 6 Powder diffraction pattern of the organic-inorganic hybrid materials obtained in Example 1 and Example 2. DETAILED DESCRIPTION OF THE INVENTION

[0029] The present invention is further described below by means of specific examples, but is not limited thereto.

[0030] The materials and reagents used in the examples are commercially available unless otherwise specified; the methods used are all prior art unless otherwise specified.

[0031] Example 1

[0032] A method for preparing an organic-inorganic hybrid material having X-ray scintillation performance comprises the steps of:

[0033] The reactant 0.2mmol UO 2 (NO 3 ) 2 6H 2 O, 3mmol H 3 BO 3 and 0.3mmol isonicotinic acid were placed in a 10ml polytetrafluoroethylene reactor, 100μL deionized water was added, fully dispersed, sealed, heated to 200℃, heated for reaction for 3 days, then gradually cooled to room temperature, filtered, the product was washed with a large amount of boiling water and ethanol in turn, and dried at room temperature to obtain an organic-inorganic hybrid material (yield 70%). In the organic-inorganic hybrid material, the central metal ion UO 2 2+ A one-dimensional chain structure is formed by linking boric acid and isonicotinic acid.

[0034] The organic-inorganic hybrid material prepared in this embodiment is irradiated with ultraviolet rays and X-rays, and the luminescence spectrum obtained is as follows: Figure 1 and Figure 2 As shown. By comparison, it is found that the two luminescence mechanisms of the two figures are the same, both originating from the intrinsic luminescence of the uranyl center. In addition, the relationship between different X-ray powers and the fluorescence intensity of the organic-inorganic hybrid material prepared in this embodiment is tested. The experimental results show that as the X-ray energy increases, the sample fluorescence intensity also increases ( Figure 3 ), and the fluorescence intensity is linearly related to the irradiated X-ray power ( Figure 4 ), which indicates that the organic-inorganic hybrid material prepared in this embodiment meets the characteristics of scintillator application.

[0035] The quantum yield of the organic-inorganic hybrid material obtained in this embodiment can reach 40.60%, showing a relatively high luminous efficiency, and can effectively convert the absorbed energy into light energy.

[0036] In order to verify the absorption efficiency of the organic-inorganic hybrid material prepared in this example for X-rays, the absorption efficiency of the organic-inorganic hybrid material prepared in this example and the commercial CsI:Tl scintillator in the X-ray energy range of 30eV-30KeV was calculated. The results are as follows: Figure 5As shown, above 22KeV, the organic-inorganic hybrid material prepared in this embodiment has a higher radiation blocking ability than CsI:Tl.

[0037] Example 2

[0038] A method for preparing an organic-inorganic hybrid material having X-ray scintillation performance comprises the steps of:

[0039] The reactant 0.2mmol UO 2 (Ac) 2 6H 2 O, 3mmol H 3 BO 3 and 0.3mmol isonicotinic acid were placed in a 10ml polytetrafluoroethylene reactor, 50μL deionized water was added, fully dispersed, sealed, heated to 180℃, heated for reaction for 3 days, then gradually cooled to room temperature, filtered, the product was washed with a large amount of boiling water and ethanol in turn, and dried at room temperature to obtain an organic-inorganic hybrid material. (yield 45%)

[0040] Its powder XRD is as follows Figure 6 As shown, it can be seen from the figure that the product structure in Example 2 is the same as the product structure in Example 1.

[0041] Comparative Example 1

[0042] A method for preparing an organic-inorganic hybrid material having X-ray scintillation performance comprises the steps of:

[0043] The reactant 0.2mmol UO 2 (NO 3 ) 2 6H 2 O, 3mmol H 3 BO 3 and 0.3mmol isonicotinic acid were placed in a 10ml polytetrafluoroethylene reactor, 100μL deionized water was added, fully dispersed, sealed, heated to 160℃, heated for 3 days, and then gradually cooled to room temperature. It was found that no product was generated in the reaction. It can be seen that the reaction temperature is crucial to the synthesis of the organic-inorganic hybrid material, and lowering the temperature is not conducive to product synthesis.

[0044] Comparative Example 2

[0045] A method for preparing an organic-inorganic hybrid material having X-ray scintillation performance comprises the steps of:

[0046] The reactant 0.2mmol UO 2 (NO 3 ) 2 6H 2 O, 0.3 mmol H 3 BO3 0.3 mmol of isonicotinic acid was placed in a 10 mL polytetrafluoroethylene reaction kettle, 100 μL of deionized water was added, and the mixture was fully dispersed, sealed, heated to 200 °C, and reacted for 3 days. Then it was gradually cooled to room temperature, and it was found that no product was formed in this reaction. Thus, it can be seen that the dosage of boric acid in the reaction is crucial for the synthesis of this organic-inorganic hybrid material. Boric acid not only serves as a component of the inorganic ligand in the material but also acts as a reaction solvent during the material preparation process, providing reaction conditions for the material preparation process.

Claims

1. A method for preparing an organic-inorganic hybrid material having X-ray scintillation performance, comprising the steps of: Uranium salt, boric acid (H3BO3), isonicotinic acid and deionized water (H2O) are fully mixed, heated for reaction, and the solid product is washed and dried to obtain an organic-inorganic hybrid material with X-ray scintillation performance.

2. The method for preparing the organic-inorganic hybrid material with X-ray scintillation performance according to claim 1, characterized in that: The uranium salt is uranyl nitrate hydrate or uranyl acetate hydrate.

3. The method for preparing the organic-inorganic hybrid material with X-ray scintillation performance according to claim 1, characterized in that: The molar ratio of the uranium salt to the boric acid is 1:5-20, preferably 1:10-15, and more preferably 1:

15.

4. The method for preparing the organic-inorganic hybrid material with X-ray scintillation performance according to claim 1, characterized in that: The molar ratio of the uranium salt to isonicotinic acid is 1:1-2, preferably 1:1.

5.

5. The method for preparing the organic-inorganic hybrid material with X-ray scintillation performance according to claim 1, characterized in that: The molar amount of the uranium salt and the volume ratio of deionized water are 2-4 mmol / mL.

6. The method for preparing the organic-inorganic hybrid material with X-ray scintillation performance according to claim 1, characterized in that: The heating reaction temperature is 170-220°C; the reaction time is 2-4 days.

7. An organic-inorganic hybrid material with X-ray scintillation performance, characterized in that: Prepared by the method according to any one of claims 1 to 6.

8. Use of the organic-inorganic hybrid material having X-ray scintillation performance prepared by the method of any one of claims 1 to 6 in X-ray scintillator materials.

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