阅读说明：本技术 金属有机杂化晶格材料及其在辐照源检测中的应用 (Metal organic hybrid lattice material and application thereof in irradiation source detection ) 是由 王建强 陆黄杰 林健 于 2020-06-04 设计创作，主要内容包括：本发明涉及一种金属有机杂化晶格材料及其在辐照源检测中的应用。本发明将水溶性钍盐与2,2’:6’,2”-三联吡啶-4’-甲酸在水和有机溶剂的混合溶剂中发生溶剂热反应,得到金属有机杂化晶格材料。晶体材料在紫外线、X射线、γ射线、β射线等辐照条件下产生辐照变色以及辐照光致荧光变化。该材料可用于大剂量射线辐照后的定性以及定量检测标定,与传统的辐照变色指示标签相比,实现可视化定性以及定量检测的同时,材料的辐照稳定性强、重复使用率高、检测限范围宽、线性关系好,可解决传统材料依赖专业的光学设备进行辐照剂量定量的问题。(The invention relates to a metal organic hybrid lattice material and application thereof in irradiation source detection. According to the invention, water-soluble thorium salt and 2,2', 6',2 '-terpyridine-4' -formic acid are subjected to solvothermal reaction in a mixed solvent of water and an organic solvent to obtain the metal organic hybrid lattice material. The crystal material generates irradiation discoloration and irradiation photoluminescence change under the irradiation conditions of ultraviolet rays, X rays, gamma rays, beta rays and the like. The material can be used for qualitative and quantitative detection calibration after large-dose ray irradiation, compared with the traditional irradiation color-changing indication label, the material realizes visual qualitative and quantitative detection, has strong irradiation stability, high reuse rate, wide detection limit range and good linear relation, and can solve the problem that the traditional material depends on professional optical equipment to carry out irradiation dose quantification.)

1. A preparation method of a metal organic hybrid lattice material is characterized by comprising the following steps:

carrying out solvothermal reaction on water-soluble thorium salt and 2,2', 6',2 '-terpyridine-4' -formic acid in a mixed solvent of water and an organic solvent at the reaction temperature of 80-120 ℃ to obtain crystals after the reaction is completed, wherein the crystals comprise the metal organic hybrid lattice material; wherein the mixed solvent also comprises 1.6-2.5 wt% of hydrochloric acid, and the molar ratio of the water-soluble thorium salt to the 2,2':6',2 '-terpyridine-4' -carboxylic acid is 1-2: 1-2.

2. The method of claim 1, wherein: the water-soluble thorium salt is thorium nitrate.

3. A metal-organic hybrid lattice material prepared by the method of any one of claims 1 or 2, having a chemical formula of [ Th₆O₄(OH)₄(H₂O)₆](H₁₀C₁₆N₃O₂)₈(COOH)₄。

4. Use of a metal organic hybrid lattice material according to claim 3 for detecting a source of radiation; the radiation source comprises ultraviolet and/or ionizing radiation rays.

5. Use according to claim 4, characterized in that: the wavelength of the ultraviolet ray is 400nm-10nm, and the photon energy is 3.10-124 eV.

6. Use according to claim 4, characterized in that: the ionizing radiation ray comprises one or more of an X ray, a gamma ray and a beta ray.

7. Use according to claim 6, characterized in that: in the qualitative detection, the detection dose of the X-ray is more than 200KGy, in the quantitative detection, the dose detection limit range of the gamma-ray is below 80KGy, and in the qualitative detection, the detection dose of the beta-ray is more than 200 KGy.

8. A method of detecting an irradiation source, said irradiation source comprising ultraviolet and/or ionizing radiation rays, characterized by: comprising a step of establishing a detection criterion and a detection step,

the step of establishing a detection standard comprises the steps of irradiating the metal-organic hybrid lattice material according to claim 3 by using the irradiation source with known wavelength or intensity, and establishing a detection standard according to the color change of the metal-organic hybrid lattice material or the change of optical signal values before and after irradiation;

the detection step comprises irradiating the metal-organic hybrid lattice material of claim 3 with an irradiation source of unknown wavelength or intensity, comparing the color change of the metal-organic hybrid lattice material or the change in optical signal value before and after irradiation with a detection standard, and performing qualitative or quantitative analysis on the irradiation source of unknown wavelength or intensity.

9. The use of a metal organic hybrid lattice material according to claim 3 for the preparation of a photoluminescent change indicator label, characterized in that: the photoluminescence change indication label comprises at least one transparent quartz container and the metal-organic hybrid lattice material sealed in the quartz container.

10. A photoluminescent change indicator label, characterized by: comprising at least one transparent quartz container and the metal-organic hybrid lattice material of claim 3 sealed in the quartz container.

Technical Field

The invention relates to the field of radiation detection materials, in particular to a metal organic hybrid lattice material and application thereof in radiation source detection.

Background

With the rapid development of nuclear energy and nuclear technology in China, radioactive isotopes and irradiation technology are widely applied in the fields of industry, agriculture, medical treatment, science, geological survey and the like in China, and therefore, the radioactive isotopes and the irradiation technology face potential ionizing radiation pollution risks. The development of an efficient, sensitive and rapid ionizing radiation detection technology is a key for preventing and treating radiation pollution and is an important precondition for guaranteeing human health and sustainable development of nuclear energy nuclear technology. The nuclear detection technology is used as a sharp tool for preventing and treating radiation pollution, and can be used for radiation safety monitoring in the fields of nuclear energy utilization, industrial automation, nuclear medicine imaging, environmental radioactive source monitoring and the like.

At present, a plurality of commercial materials applied to ionizing radiation measurement are developed, and an irradiation photoluminescence material serving as a luminous signal output type irradiation detection material is widely applied to X, gamma and other ray detection, but the traditional irradiation photoluminescence materials (glass, ceramics, high polymer, inorganic salt crystal and the like) still have the problems of low sensitivity, narrow detection limit range, poor linear relation, complex test equipment and data processing and the like, and the stability and the reuse rate of other parts of materials are also required to be improved. The traditional irradiation photoluminescence detection material has poor ray blocking capability, so that the irradiation stability is poor and the sensitivity is low, thereby limiting the application prospect of the material, relying on optical instrument equipment for testing and analyzing when quantifying the ray dose, and being an irradiation detection mode with low efficiency and poor economy.

While commercial radiation color-changing indicator labels generally use polyvinyl butyral (PVB) and ethanol-based dyes, the material can only be used as a disposable radiation detection test paper. Meanwhile, in the detection process, a detector identifies the color change of the indicating label paper after irradiation by naked eyes, compares the color change with the chromaticity of a standard indicating label card, and performs qualitative or semi-quantitative irradiation detection analysis, wherein the accurate quantitative analysis of the ray dose is yet to be improved.

Disclosure of Invention

In order to solve the technical problems, the invention aims to provide a metal organic hybrid lattice material and an application thereof in detecting an irradiation source.

The first purpose of the invention is to provide a preparation method of a metal organic hybrid lattice material, which comprises the following steps:

carrying out solvothermal reaction on water-soluble thorium salt and 2,2', 6',2 '-terpyridine-4' -formic acid in a mixed solvent of water and an organic solvent at the reaction temperature of 80-120 ℃ to obtain blocky transparent crystals after complete reaction, wherein the blocky transparent crystals comprise metal organic hybrid lattice materials; wherein, the mixed solvent also comprises 1.6 to 2.5 weight percent of inorganic acid, and the molar ratio of the water-soluble thorium salt to the 2,2':6',2 '-terpyridine-4' -formic acid is 1 to 2: 1-2.

Further, the water-soluble thorium salt is thorium nitrate.

Furthermore, the concentration of the water-soluble thorium salt in the solvent thermal reaction system is 0.025mmol/mL-0.5 mmol/mL.

Further, the volume ratio of water to the organic solvent is 1-3: 1-3.

Further, the organic solvent is selected from N, N' -Dimethylformamide (DMF), and the volume ratio of water to DMF is 1-3: 1-3.

Further, the solvothermal reaction time is 1-2 days.

In the present invention, 1.6 to 2.5 wt% of the inorganic acid means that the inorganic acid accounts for 1.6 to 2.5 wt% of the whole reaction solution.

In the above preparation method, the inorganic acid functions to adjust the reaction pH, and the concentration thereof refers to the mass fraction of the inorganic acid in the mixed solvent. The water is used for dissolving thorium salt, and the organic solvent is used for dissolving 2,2', 6',2 '-terpyridine-4' -formic acid.

The second purpose of the invention is to protect the metal organic hybrid lattice material prepared by the preparation method, and the chemical formula is [ Th₆O₄(OH)₄(H₂O)₆](H₁₀C₁₆N₃O₂)₈(COOH)₄. The metal center of the metal-organic hybrid lattice material is tetravalent thorium element, and the ligand is 2,2', 6',2 '-terpyridine-4' -formic acid.

The third purpose of the invention is to disclose the application of the metal organic hybrid lattice material in detecting an irradiation source; the radiation source comprises ultraviolet and/or ionizing radiation rays.

Further, the ultraviolet ray has a wavelength of 400nm to 10nm and a photon energy of 3.10 to 124 eV.

Further, the ultraviolet quantitative detection energy range is 0-4.2 mJ. When the energy is more than 4.2mJ, the fluorescence signal value is unchanged and is not changedThen, the product is processedAnd (5) carrying out quantitative detection.

Further, the ionizing radiation rays include one or more of X-rays, gamma-rays and beta-rays.

Furthermore, the qualitative detection dose of the X-ray is more than 200KGy, the dose detection limit range of the gamma-ray is about 0-80KGy, and the qualitative detection dose of the beta-ray is more than 200 KGy.

The metal organic hybrid lattice material of the invention generates fluorescence change under the irradiation of ultraviolet rays and ionizing radiation rays due to the intrinsic photoluminescence property of the ligand, and the characteristic is the irradiation fluorescence change characteristic; meanwhile, under different irradiation conditions, the metal organic hybrid lattice material can generate different color changes, namely the irradiation color change characteristic. By utilizing the two characteristics, the method can be applied to detecting the irradiation source to realize qualitative or quantitative analysis of the irradiation source.

After the metal organic hybrid lattice material is subjected to irradiation fluorescence change and irradiation discoloration, the fluorescence characteristic peak signal intensity value before irradiation can be recovered under the heating condition, so that the material can be recycled in the irradiation detection process.

Further, after irradiation, the material can be heated at 100-150 ℃ for 1-3 days to recover the fluorescence characteristic peak signal intensity value. Because the irradiation excites the organic ligand to generate free radicals, an Electron Paramagnetic Resonance (EPR) spectrum is used for analyzing and generating free radical signals after the irradiation, free electrons are transferred in a pyridine ring of the ligand, pi-pi interaction in the structure is enhanced at the same time, so that the fluorescence of the material is changed, the free radical signals disappear after heating, and the enhanced fluorescence characteristic peak signals are restored to initial values.

It is a fourth object of the present invention to provide a method of inspecting an irradiation source, the irradiation source including ultraviolet rays and/or ionizing radiation rays, the method of inspecting an irradiation source including a step of establishing an inspection standard and a step of inspecting,

the step of establishing the detection standard comprises the steps of irradiating the metal-organic hybrid lattice material by adopting an irradiation source with known wavelength or intensity, and establishing the detection standard according to the color change of the metal-organic hybrid lattice material or the change of optical signal values before and after irradiation;

the detection step comprises the steps of irradiating the metal-organic hybrid lattice material by using an irradiation source with unknown wavelength or intensity, comparing the color change of the metal-organic hybrid lattice material or the change of optical signal values before and after irradiation with a detection standard, and carrying out qualitative or quantitative analysis on the irradiation source with unknown wavelength or intensity.

Furthermore, the wavelength of the ultraviolet light is 400nm-10nm, the photon energy is 3.10-124eV, and the detection energy range is about 0-4.2 mJ.

Further, the ionizing radiation rays include one or more of X-rays, gamma-rays and beta-rays.

Further, the step of establishing a detection standard may comprise establishing a qualitative detection standard or a quantitative detection standard.

And establishing a qualitative detection standard, wherein the establishment of a visual irradiation discoloration qualitative detection standard or a visual photoluminescence change qualitative detection standard is included.

And establishing a visual irradiation discoloration qualitative detection standard, irradiating the original metal organic hybrid lattice material under irradiation sources with different known wavelengths or intensities, recording the color generated by the metal organic hybrid lattice material, and establishing the relationship between the wavelengths or intensities of different irradiation sources and the color to serve as the detection standard.

The recording mode can adopt a microscope and an image acquisition system to shoot.

Establishing a visual photoluminescence change qualitative detection standard, irradiating the original metal organic hybrid lattice material under irradiation sources with different known wavelengths or intensities, then carrying out photo acquisition on the lattice material before and after irradiation by using a picture acquisition system, and establishing the relationship between different irradiation sources and fluorescence characteristic peaks and signal intensities by using a fluorescence spectrometer, wherein the relationship is used as the detection standard. When the quantitative detection standard is established, the original metal organic hybrid lattice material is irradiated under irradiation sources with different known wavelengths or intensities, then the fluorescence signal intensity of the lattice material before and after irradiation is collected, the color rendering index is linearly fitted with the wavelength or dose of the irradiation source, and a linear calibration curve between the wavelength or dose of the irradiation source and the color rendering index is established. When the fluorescence signal intensity of the lattice material before and after irradiation is collected, a photographic collection system can be used for collecting and fluorescence color in the picture can be extracted by image processing software such as Photoshop and the like.

The detection step may comprise qualitative or quantitative detection.

When the qualitative detection is carried out, the method comprises visual irradiation color change qualitative detection or visual photoluminescence change qualitative detection.

When the visual irradiation discoloration qualitative detection is carried out, an irradiation source (namely, an irradiation source to be detected) with unknown wavelength or intensity is adopted to irradiate the original metal organic hybrid lattice material, the color generated by the original metal organic hybrid lattice material is compared with the visual irradiation discoloration qualitative detection standard, and the known wavelength or intensity corresponding to the same color change is found out, so that the type of the irradiation source to be detected is determined.

When the visual photoluminescence change qualitative detection is carried out, an irradiation source (namely, an irradiation source to be detected) with unknown wavelength or intensity is adopted to irradiate the original metal organic hybrid lattice material, then, a picture acquisition system is utilized to acquire the fluorescence characteristic peak and the signal intensity of the irradiated lattice material, the fluorescence characteristic peak and the signal intensity are compared with the visual photoluminescence change qualitative detection standard, the same fluorescence characteristic peak and the irradiation source type corresponding to the signal intensity are found out, and therefore the type of the irradiation source to be detected is determined.

When quantitative detection is carried out, an irradiation source (namely, an irradiation source to be detected) with unknown wavelength or intensity is adopted to irradiate the original metal organic hybrid lattice material, then the fluorescence signal intensity of the irradiated lattice material is collected, and the wavelength or dose corresponding to the color rendering index of the fluorescence signal intensity is found out on a linear calibration curve, so that the accurate wavelength or intensity of the irradiation source to be detected is determined.

Further, during qualitative detection, the detection dose of X-rays is greater than 200KGy, the detection dose of gamma-rays is greater than 200KGy, and the detection dose of beta-rays is greater than 200 KGy.

Furthermore, during quantitative detection, the dosage detection limit of gamma rays is about 0-80 KGy.

Further, when the signal change of the ultraviolet radiation is collected, the method also comprises the step of collecting the signal of the metal organic hybrid lattice material under a xenon lamp of a solid-state spectrometer.

A fifth object of the present invention is to claim the application of the above metal-organic hybrid lattice material in the preparation of a photoluminescent change indicator label, which comprises at least one transparent quartz container and the metal-organic hybrid lattice material sealed in the quartz container.

Further, the blocky transparent crystal prepared by the method is ground into powder and is packaged in a quartz container to prepare the photoluminescence change indication label, namely the irradiation detection component is formed. After the metal organic hybrid lattice material is subjected to photoluminescence change and photochromic behavior, the fluorescence characteristic peak signal intensity value before irradiation can be recovered under the heating condition, so that the photoluminescence change indication label can be heated for repeated use.

A sixth object of the present invention is to provide a photoluminescent change indicator label, comprising at least one transparent quartz container and the above metal-organic hybrid lattice material sealed in the quartz container.

Under the irradiation of X, gamma and beta rays with large dose of 200KGy, the color of the crystal in the photoluminescence change indication label is changed from pink to yellow brown, so that the visual irradiation qualitative detection of large dose of rays can be carried out, and meanwhile, the color change phenomenon can be also shown under the high-frequency ultraviolet irradiation, so that the visible irradiation qualitative detection of ultraviolet rays can be used.

Meanwhile, when the crystal in the photoluminescent change indication label receives radiation irradiation with different doses, the change of the photoluminescent spectrum and the color of the fluorescent photo can generate a regular change trend along with the dose, and the regular change trend is acquired and analyzed by different optical devices and camera systems.

The invention takes 2,2', 6',2 '-terpyridine-4' -formic acid as ligand, coordinates with tetravalent thorium element under solvothermal condition for crystallization, and the crystal material generates photochromism and photoluminescence change under irradiation conditions of high-frequency ultraviolet ray, X ray, gamma ray, beta ray and the like. The material can be used for qualitative and quantitative detection calibration after large-dose ray irradiation, compared with the traditional irradiation color-changing indication label, the material realizes visual qualitative and quantitative detection, has strong irradiation stability, high reuse rate, wide detection limit range and good linear relation, and can solve the problem that the traditional material depends on professional optical equipment to carry out irradiation dose quantification.

By the scheme, the invention at least has the following advantages:

(1) compared with the traditional hybrid materials, inorganic materials, high molecular materials and the like, the invention introduces actinide metal thorium and organic photoluminescence ligands to construct metal-organic hybrid lattice materials as novel irradiation photoluminescence detection materials, and has wider detection limit range and better linear relation;

(2) the metal organic hybrid lattice material has strong irradiation stability and high repeated utilization rate;

(3) the metal organic hybrid lattice material can realize the visual qualitative detection of rays by using the radiation discoloration effect and the visual quantitative detection of rays by using the radiation photoluminescence change;

(4) the original crystal material is designed into a packaging component, so that the testing and the use under an irradiation field are convenient, the crystal material can be repeatedly utilized after being heated, the stability of the material is ensured, and the crystal material cannot be damaged and influenced by external environments such as wind erosion and the like;

(5) the irradiation photoluminescence quantitative indication label provided by the invention is a novel visual irradiation indication label designed on the basis of a commercial irradiation color-changing indication label, is also a novel irradiation dose calibration method, achieves a very wide irradiation detection limit range, realizes accurate detection of dose by using the change of a fluorescence signal, and can solve the problem that the traditional material needs to depend on professional optical equipment for irradiation dose quantification.

The foregoing description is only an overview of the technical solutions of the present invention, and in order to make the technical solutions of the present invention more clearly understood and to implement them in accordance with the contents of the description, the following description is made with reference to the preferred embodiments of the present invention and the accompanying detailed drawings.

Drawings

FIG. 1 is a schematic structural view of a crystalline material prepared in example 1 of the present invention;

FIG. 2 is a powder diffraction pattern of crystalline material tested in example 1 of the present invention before and after irradiation;

FIG. 3 is a graph showing the thermal stability analysis of the crystalline material tested in example 2 of the present invention;

FIG. 4 shows the fluorescence stability test results of the crystalline material tested in example 3 of the present invention after irradiation;

FIG. 5 is a diagram of an irradiation detection device and an irradiation fluorescence cycle designed in embodiment 4 of the present invention;

FIG. 6 is a graph of the free radical signal of the crystal before and after UV radiation exposure as tested in example 4 of the present invention;

FIG. 7 is a crystal discoloration diagram of example 5 under irradiation of different irradiation sources;

FIG. 8 is a plot of the photoluminescence of crystals before and after irradiation with 200KGy beta radiation as tested in example 6 of the present invention;

FIG. 9 is a plot of the photoluminescence of the crystals before and after irradiation with 200KGy gamma rays as tested in example 6 of the present invention;

FIG. 10 is a plot of the photoluminescence of the crystals before and after irradiation with 200KGy X-rays as tested in example 6 of the present invention;

FIG. 11 is a graph of a linear fitting quantitative method of the irradiation photoluminescence indicator label and the dose after different doses of gamma ray irradiation in example 7 of the invention;

FIG. 12 is a schematic view of irradiation detection under X-ray irradiation field of Shanghai light source BL14W1 line station in embodiment 8 of the present invention;

FIG. 13 is a graph of the UV-visible absorbance of crystals after exposure to various doses of UV radiation as tested in example 9 of the present invention;

FIG. 14 is a photograph of the photoluminescence of the crystals after exposure to different doses of UV radiation as tested in example 9 of the present invention;

FIG. 15 is a graph of the photoluminescence spectra after exposure to different doses of UV radiation as tested in example 9 of the invention;

FIG. 16 is a CIE chart after exposure to different doses of UV radiation as tested in example 9 of the present invention;

FIG. 17 is a graph of dose versus spectral peak intensity for different doses of UV radiation as tested in example 9 of the present invention.

Detailed Description

The following examples are given to further illustrate the embodiments of the present invention. The following examples are intended to illustrate the invention but are not intended to limit the scope of the invention.