Multicolor rare earth scintillation crystal and preparation method and application thereof

Abstract

The invention discloses a multicolor rare earth scintillation crystal and a preparation method and application thereof, and belongs to the field of luminescent crystal materials and scintillation materials. The chemical formula of the multicolor rare earth scintillation crystal is [Ln (BDC) 1.5 (DMA)] n, wherein Ln is rare earth ion Tb < 3 + > and / or Eu < 3 + >, BDC is deprotonated terephthalic acid, and DMA is N, N-dimethylacetamide; n is infinity and represents continuous repeated infinite extension. The multicolor rare earth scintillation crystal has potential application value in multicolor fluorescent materials, X-ray detection and imaging materials and radiation detection dosimeters. The preparation method disclosed by the invention can be simply realized through solution reaction under relatively mild conditions, and is low in cost and high in industrial feasibility.

Description

Technical Field

[0001] The present application relates to a multi-color rare earth scintillation crystal and a preparation method and application thereof, belonging to the field of luminescent crystal materials and scintillation materials. Background Art

[0002] With the rapid development of science and technology, radiation detectors play a huge role in medical diagnosis and treatment, homeland security, astrophysics, and space exploration. Currently, the most widely used radiation detector is the indirect radiation detector, the core of which is the scintillator. Scintillator is a material that can convert high-energy X-rays and gamma-rays into low-energy ultraviolet / visible light. Traditional inorganic scintillators such as CsI:Tl, Bi4Ge3O 12 (BGO), PbWO4 (PWO), YAlO3:Ce, YLu2(SiO4)3:Ce (LYSO:Ce) have been widely used in the market, but these materials are usually grown into bulk crystals at temperatures exceeding 1700°C, and the preparation conditions are harsh and the cost is high. Organic scintillators such as naphthalene and anthracene are easy to synthesize, have a fast response time, and are easy to composite with flexible substrates, but they are mostly composed of light atoms such as C, N, and O, and have poor absorption of X-rays. Metal-organic frameworks (MOFs) are crystalline materials constructed from inorganic nodes (metal atoms or metal clusters) and organic ligands. They have the advantages of functional adjustability, structural designability, and mild synthesis process, and have great potential in the field of radiation detection or medical imaging. However, the organic scintillators composed of Pb 2+ 、Ba 2+ 、Zr 4+ or Sr 2+ The RL properties of the constructed blinking MOFs come from ligand luminescence and can only show relatively limited blinking intensity and sensitivity. Summary of the Invention

[0003] In view of the above, the present application aims to address at least one of the problems existing in existing scintillator technology, namely, harsh reaction conditions, long synthesis cycles, and limited light output. The present application provides a rare earth scintillating material that can be synthesized using a simple solvothermal reaction. The compound, composed of heavy rare earth metals as inorganic components, is capable of achieving efficient X-ray attenuation; the compound also exhibits efficient photoluminescence and scintillation luminescence properties, with strong scintillation luminescence intensity, high scintillation light output, and a low X-ray detection limit. Furthermore, by simply adjusting the ratio of Tb and Eu elements in the reaction system, crystalline compounds with a variety of photoluminescence and scintillation luminescence colors can be prepared.

[0004] According to a first aspect of the present application, a multi-color rare earth scintillation crystal is provided. The multi-color rare earth scintillation crystal has good water stability, thermal stability, and radiation stability, and exhibits multi-color luminescence visible to the naked eye under ultraviolet light and X-ray irradiation. The multi-color rare earth scintillation crystal exhibits a green (Tb) luminescence visible to the naked eye under ultraviolet light and X-ray irradiation at 365 nm. 3+ ) or red (Eu 3+ ) fluorescence, and by changing the Tb 3+ and Eu 3+ By adjusting the addition ratio, fluorescent scintillating crystals with various luminescent colors, from green to red, can be obtained. They have potential applications in multicolor fluorescent materials, X-ray detection and imaging materials, and radiation detection dosimeters.

[0005] A multi-color rare earth scintillation crystal, wherein the chemical formula of the multi-color rare earth scintillation crystal is [Ln(BDC) 1.5 (DMA)] n ;

[0006] Among them, Ln is the rare earth ion Tb 3+ and / or Eu 3+ , BDC is deprotonated terephthalic acid, DMA is N,N-dimethylacetamide;

[0007] n is ∞, which means it will be repeated and extended infinitely.

[0008] Ln can be selected from any one of Tb and Eu or different ratios between the two.

[0009] Alternatively, when Ln is a rare earth ion Tb 3+ and Eu 3+ When Eu 3+ The proportion is 0.5% to 15%.

[0010] Optionally, the multi-color rare earth scintillation crystal is a three-dimensional framework structure, and its minimum asymmetric structural unit contains 1.5 BDC 2- Ligand, 1 Ln 3+ Metal ions, 1 DMA molecule;

[0011] Ln 3+ The metal ion is Tb in an octa-coordinate configuration. 3+ / Eu 3+ Metal ions;

[0012] Ln 3+ Metal ions are respectively combined with the four BDC 2- Seven O atoms on the carboxylate group of the ligand and one O atom on DMA are coordinated.

[0013] Optionally, the multi-color rare earth scintillating crystal belongs to the triclinic system and has a P-1 space group structure;

[0014] The unit cell parameters of the crystal are: α=93~94°, β=114~115°, γ=116~118°;

[0015] Preferably, α=93.1~93.5°, β=114.1~114.7°, γ=116.5~117.2°.

[0016] Preferably, α=93.17-93.38°, β=114.28-114.49°, and γ=116.93-117.12°.

[0017] Optionally, the multi-color rare earth scintillation crystal has a size of 2 mm×2 mm×1 mm.

[0018] Optionally, the thermal decomposition temperature of the multi-color rare earth scintillation crystal is ≥200°C.

[0019] Preferably, the thermal decomposition temperature of the multi-color rare earth scintillation crystal is ≥250° C. The above thermal decomposition temperature indicates that the multi-color rare earth scintillation crystal has good thermal stability.

[0020] Optionally, the multi-color rare earth scintillation crystal can emit light of multiple colors under ultraviolet light or X-ray irradiation.

[0021] The multi-color rare earth scintillation crystal is usually a colorless transparent block crystal with a three-dimensional structure. 1.5 (DMA)] n It emits bright green light under the excitation of light with a wavelength of 290-450nm and X-rays. 1.5 (DMA)] n It emits bright red light under the excitation of light with a wavelength of 290-450nm and X-rays.

[0022] The multi-color rare earth scintillation crystal is prepared by changing the Tb 3+ and Eu 3+ The addition ratio of Tb and Eu can be adjusted to obtain fluorescent scintillating crystals with various luminescent colors from green to red. The luminescent colors of the multi-color rare earth scintillating crystals with different ratios of Tb and Eu can be any one of green, light green, yellow-green, yellow, orange-yellow, orange, orange-red, and red.

[0023] Among them, ([Tb(BDC) 1.5 (DMA)] n) is a Tb-based rare earth scintillating material, [Eu(BDC) 1.5 (DMA)] n ) is Eu-based rare earth scintillating material.

[0024] Optionally, the Tb-based rare earth scintillating material ([Tb(BDC) 1.5 (DMA)] n ) has a green light RGB color coordinate of (0.29-0.31, 0.61-0.63), and the Eu-based rare earth scintillating material ([Eu(BDC) 1.5 (DMA)] n )'s red light RGB color coordinates are (0.65~0.66,0.33~0.34).

[0025] Preferably, the Tb-based rare earth scintillating material ([Tb(BDC) 1.5 (DMA)] n ) has a green light RGB color coordinate of (0.295-0.305, 0.618-0.625), and the Eu-based rare earth scintillating material ([Eu(BDC) 1.5 (DMA)] n )'s red light RGB color coordinates are (0.652~0.658,0.335~0.337).

[0026] More preferably, the Tb-based rare earth scintillating material ([Tb(BDC) 1.5 (DMA)] n ) has a green light RGB color coordinate of (0.300, 0.621), and the Eu-based rare earth scintillating material ([Eu(BDC) 1.5 (DMA)] n )'s red light RGB color coordinates are (0.655, 0.336).

[0027] Optionally, the RGB color coordinates of the rare earth scintillating materials with different proportions of Tb and Eu are in the range of (0.300-0.655, 0.621-0.336).

[0028] Optionally, the photoluminescence quantum yield of the Tb-based rare earth scintillating material is ≥70%, and the photoluminescence quantum yield of the Eu-based rare earth scintillating material is ≥50%;

[0029] Preferably, the photoluminescence quantum yield of the Tb-based rare earth scintillating material is ≥80%, and the photoluminescence quantum yield of the Eu-based rare earth scintillating material is ≥60%.

[0030] Optionally, the luminescence lifetime of the multi-color rare earth scintillation crystal is 1.0 to 4.0 ms.

[0031] Preferably, the luminescence lifetime of the multi-color rare earth scintillation crystal is 1.10 to 2.50 ms.

[0032] More preferably, the luminescence lifetime of the multi-color rare earth scintillation crystal is 1.20 to 1.50 ms.

[0033] Optionally, the Tb-based rare earth scintillating material ([Tb(BDC) 1.5 (DMA)] n ) has an X-ray light output of ≥20,000 photons / MeV, and the Eu-based rare earth scintillating material ([Eu(BDC) 1.5 (DMA)] n ) has an X-ray light output ≥ 1000 photons / MeV.

[0034] Preferably, the Tb-based rare earth scintillating material ([Tb(BDC) 1.5 (DMA)] n ) has an X-ray light output of ≥30,000 photons / MeV, and the Eu-based rare earth scintillating material ([Eu(BDC) 1.5 (DMA)] n ) has an X-ray light output ≥ 2000 photons / MeV.

[0035] Optionally, the scintillation intensity of the Tb-based rare earth scintillating material is 20 times that of a bismuth germanium oxide (BGO) scintillating crystal, and the scintillation intensity of the Eu-based rare earth scintillating material is 1 times that of a bismuth germanium oxide (BGO) scintillating crystal.

[0036] Preferably, the scintillation intensity of the Tb-based rare earth scintillating material is 30 to 50 times that of the bismuth germanium oxide (BGO) scintillation crystal, and the scintillation intensity of the Eu-based rare earth scintillating material is 1 to 2 times that of the bismuth germanium oxide (BGO) scintillation crystal.

[0037] Optionally, the X-ray detection lower limit of the Tb-based rare earth scintillating material is ≤300 nGy / s, and the X-ray detection lower limit of the Eu-based rare earth scintillating material is ≤3 μGy / s.

[0038] Preferably, the X-ray detection lower limit of the Tb-based rare earth scintillating material is ≤200 nGy / s, and the X-ray detection lower limit of the Eu-based rare earth scintillating material is ≤2 μGy / s.

[0039] Preferably, the X-ray detection lower limit of the Tb-based rare earth scintillating material is ≤100 nGy / s, and the X-ray detection lower limit of the Eu-based rare earth scintillating material is ≤1 μGy / s.

[0040] More preferably, the X-ray detection lower limit of the Tb-based rare earth scintillating material is 73.1 nGy / s, and the X-ray detection lower limit of the Eu-based rare earth scintillating material is 0.67 μGy / s.

[0041] According to a second aspect of the present application, a method for preparing the multi-color rare earth scintillation crystal is provided. The method can be simply achieved through solution reaction under relatively mild conditions, has low cost, and is highly industrially feasible.

[0042] The method for preparing the multi-color rare earth scintillation crystals is as follows: placing a mixed solution containing terephthalic acid, a Ln metal source, and a solvent in a sealed container and reacting the mixture to obtain the multi-color rare earth scintillation crystals;

[0043] The solvent includes N,N-dimethylacetamide and hydrogen halide, and at least one of water, methanol and ethanol.

[0044] Optionally, the Ln metal source is selected from at least one of nitrates, acetates, and chlorides corresponding to Tb and Eu;

[0045] The hydrogen halide is selected from at least one of HCl and HBr.

[0046] Optionally, the Tb metal source is selected from at least one of Tb(NO3)3(H2O)6, Tb(CH3COO)3(H2O)6, and TbCl3(H2O)6; the Eu metal source is selected from at least one of Eu(NO3)3(H2O)6, Eu(CH3COO)3(H2O)6, and EuCl3.

[0047] Optionally, the solvent is N,N-dimethylacetamide, water and hydrogen halide solution.

[0048] Optionally, the molar ratio of terephthalic acid to Ln metal source is 1:1 to 1:2;

[0049] The molar amount of the Ln metal source is calculated based on the molar amount of the Ln element in the metal source.

[0050] Optionally, the molar ratio of the organic ligand terephthalic acid to the Ln metal source is independently selected from any value among 1:1.0, 1:1.1, 1:1.2, 1:1.3, 1:1.4, 1:1.5, 1:1.6, 1:1.7, 1:1.8, 1:1.9, 1:2.0 or any range therebetween.

[0051] Optionally, the multi-color rare earth scintillation crystal can be prepared by changing the Tb 3+ and Eu 3+ The addition ratio is obtained, Tb 3+ and Eu 3+The addition ratio can be selected from any one of 0.995:0.005, 0.99:0.01, 0.98:0.02, 0.97:0.03, 0.96:0.04, 0.95:0.05, 0.94:0.06, 0.93:0.07, 0.92:0.08, 0.91:0.09, 0.9:0.1, and 0.85:0.15.

[0052] Optionally, the molar volume ratio of the Ln metal source to the total amount of solvent is 0.1 mmol: 3 to 8 mL.

[0053] Optionally, the molar volume ratio of the Ln metal source to N,N-dimethylacetamide is 0.1 mmol:3-5 mL.

[0054] Optionally, the molar volume ratio of the Ln metal source to water, methanol or ethanol is 0.1 mmol:1-3 mL.

[0055] Optionally, the molar volume ratio of the Ln metal source to the hydrogen halide is 0.1 mmol: 0.05 to 0.2 mL.

[0056] Optionally, the reaction temperature is 80 to 140° C., and the reaction time is 24 to 72 hours;

[0057] Preferably, the reaction temperature is 90-120° C., and the reaction time is 36-54 hours.

[0058] Optionally, the reaction temperature is independently selected from any value among 80°C, 85°C, 90°C, 95°C, 100°C, 105°C, 110°C, 115°C, 120°C, 125°C, 130°C, 135°C, 140°C or any range therebetween.

[0059] Optionally, the reaction time is independently selected from any value among 24h, 30h, 36h, 42h, 48h, 54h, 60h, 66h, 72h, or any range value therebetween.

[0060] As a preferred embodiment, the method for preparing the multi-color rare earth scintillation crystal comprises:

[0061] Tb(NO3)3(H2O)6 and terephthalic acid at a molar ratio of 1:1 were placed in a 10 mL glass vial, and then DMA, water, and HCl solvent were added to carry out a solvothermal reaction. The volume ratio of Tb(NO3)3(H2O)6 to DMA was 0.1 mmol:3 mL, the volume ratio of Tb(NO3)3(H2O)6 to water was 0.1 mmol:2 mL, and the volume ratio of Tb(NO3)3(H2O)6 to HCl was 0.1 mmol:0.1 mL. The reaction temperature was 100°C and the reaction time was 48 hours. After the reaction was completed, it was cooled to room temperature, filtered, and washed with DMA and ethanol to obtain colorless block crystals, namely the three-dimensional structure [Tb(BDC) 1.5 (DMA)] n The yield was 59%.

[0062] According to a third aspect of the present application, an application of the multi-color rare earth scintillation crystal described above is provided.

[0063] The above-mentioned multi-color rare earth scintillation crystal is used in multi-color fluorescent materials, light-emitting diodes, X-ray detection materials, radiation detection dosimeters, and radiation imaging devices.

[0064] The beneficial effects of this application include:

[0065] (1) The multi-color rare earth scintillation crystal provided in this application is used as a fluorescent scintillation material, which exhibits multiple colors of photoluminescence and scintillation luminescence visible to the naked eye under ultraviolet light and X-ray irradiation, and can be used to make multi-color fluorescent materials, high-energy radiation detection materials and devices, etc.

[0066] (2) The multi-color rare earth scintillation crystal provided by the present application has good thermal stability and excellent X-ray scintillation performance. Experimental determination shows that the upper limit of thermal stability of this type of scintillation material is as high as 250°C. The compound [Tb(BDC) 1.5 DMA] n The scintillation intensity is about 40.48 times that of bismuth germanium oxide (BGO) scintillation crystal. The compound [Eu(BDC) 1.5 DMA] n The scintillation intensity is approximately 1.85 times that of BGO, and it overcomes the drawbacks of heavy metal pollution and high industrial energy consumption in traditional commercial scintillators, making it of great commercial value in the field of scintillating materials. The crystal provided by the present invention has good X-ray response sensitivity and irradiation stability.

[0067] (3) The multi-color rare earth scintillation crystal according to the present application can be used as an X-ray scintillation material to achieve X-ray scintillation detection with high sensitivity, low detection limit and stable light response. 1.5 (DMA)] nand compounds [Eu(BDC) 1.5 (DMA)] n The materials exhibit sensitive X-ray detection capabilities, with detection limits as low as 73.1 nGy / s and 0.67 μGy / s, respectively, both below the standard medical diagnostic dose of 5.50 μGy / s. Their scintillation light outputs are 41,317 and 2,127 photons / MeV, respectively. The high scintillation light output and low X-ray detection limit of these rare earth scintillating materials can further improve the spatial resolution of imaging displays, which is crucial for high-quality imaging. This makes them commercially valuable in the fields of high-energy particle detection and imaging display materials.

[0068] (4) The preparation method of the multi-color rare earth scintillation crystal provided by the present invention is simple, and the prepared crystal has high purity and good crystallinity as a fluorescent scintillation material, and is suitable for large-scale industrial production. BRIEF DESCRIPTION OF THE DRAWINGS

[0069] Figure 1 The crystal material of sample #1 [Tb(BDC) 1.5 (DMA)] n Schematic diagram of the coordination environment.

[0070] Figure 2 The crystal material of sample #1 [Tb(BDC) 1.5 (DMA)] n X-ray powder diffraction pattern of .

[0071] Figure 3 The crystal material of sample #1 [Tb(BDC) 1.5 (DMA)] n Photoluminescence spectrum.

[0072] Figure 4 The crystal material of sample #1 [Tb(BDC) 1.5 (DMA)] n luminous color coordinate diagram.

[0073] Figure 5 The crystal material of sample #1 [Tb(BDC) 1.5 (DMA)] n Photoluminescence quantum yield diagram.

[0074] Figure 6 The crystal material of sample #1 [Tb(BDC) 1.5 (DMA)] n Fluorescence lifetime spectrum.

[0075] Figure 7 The X-ray dose rate of sample #1 crystal material [Tb(BDC) 1.5(DMA)] n , LYSO:Ce, BGO and sample #2 crystal materials [Eu(BDC) 1.5 (DMA)] n Comparison of scintillation emission spectra.

[0076] Figure 8 The crystal material of sample #1 [Tb(BDC) 1.5 (DMA)] n Linear plot of scintillation intensity versus X-ray dose.

[0077] Figure 9 The crystal material of sample #1 [Tb(BDC) 1.5 (DMA)] n X-ray detection limit diagram.

[0078] Figure 10 The crystal material of sample #1 [Tb(BDC) 1.5 (DMA)] n Thermogravimetric curve of .

[0079] Figure 11 The crystal material of sample #1 [Tb(BDC) 1.5 (DMA)] n and sample #2 crystal material [Eu(BDC) 1.5 (DMA)] n Radiation stability diagram.

[0080] Figure 12 The crystal material of sample #2 [Eu(BDC) 1.5 (DMA)] n X-ray powder diffraction pattern of .

[0081] Figure 13 The crystal material of sample #2 [Eu(BDC) 1.5 (DMA)] n Photoluminescence spectrum.

[0082] Figure 14 The crystal material of sample #2 [Eu(BDC) 1.5 (DMA)] n luminous color coordinate diagram.

[0083] Figure 15 The crystal material of sample #2 [Eu(BDC) 1.5 (DMA)] n Photoluminescence quantum yield diagram.

[0084] Figure 16 The crystal material of sample #2 [Eu(BDC) 1.5 (DMA)]n Fluorescence lifetime spectrum.

[0085] Figure 17 The crystal material of sample #2 [Eu(BDC) 1.5 (DMA)] n Linear plot of scintillation intensity versus X-ray dose.

[0086] Figure 18 The crystal material of sample #2 [Eu(BDC) 1.5 (DMA)] n X-ray detection limit diagram.

[0087] Figure 19 Is the sample #2 crystal material [Eu(BDC) 1.5 (DMA)] n Thermogravimetric curve of . DETAILED DESCRIPTION

[0088] The present application is described in detail below with reference to embodiments, but the present application is not limited to these embodiments.

[0089] Unless otherwise specified, the raw materials in the examples of this application were purchased through commercial channels.

[0090] Unless otherwise specified, conventional methods were used for testing, and instrument settings were those recommended by the manufacturer.

[0091] The analytical measuring instruments used in the examples of this application are as follows:

[0092] Single crystal structure characterization: collected on a Rigaku FR-X single crystal diffractometer, Mo target, K α Radiation source (λ=0.7107nm), test temperature 293K.

[0093] Thermogravimetric analysis: performed using a METTLER TOLEDO thermogravimetric analyzer.

[0094] Photoluminescence spectra, quantum yields, and decay lifetimes were measured using an FLS1000 fluorescence spectrometer.

[0095] The scintillation performance (scintillation intensity, X-ray detection limit and X-ray irradiation stability) was carried out on an X-ray scintillation spectrometer.

[0096] XRD was performed using a Rigaku Miniflex 600 X-ray diffractometer.

[0097] Example 1

[0098] Tb(NO3)3(H2O)6 (0.1mmol) and terephthalic acid (0.1mmol) were placed in a 10mL glass vial in a 1:1 molar ratio, and then DMA (3ml), water (2ml), and HCl (0.1ml) were added. The mixed solution was placed in a sealed container for reaction at a temperature of 100°C for 48h. After the reaction was completed, the mixture was cooled to room temperature, filtered, washed with DMA and ethanol, and obtained as colorless transparent block crystals [Tb(BDC) 1.5 (DMA)] n , recorded as sample #1.

[0099] Example 2

[0100] Eu(NO3)3(H2O)6 (0.1mmol) and terephthalic acid (0.1mmol) were placed in a 10mL glass vial in a 1:1 molar ratio, and then DMA (3ml), water (2ml), and HCl (0.1ml) solvent were added. The mixed solution was placed in a sealed container for reaction at a temperature of 100°C for 48h. After the reaction was completed, it was cooled to room temperature, filtered, washed with DMA and ethanol, and obtained as colorless transparent block crystals [Eu(BDC) 1.5 (DMA)] n , recorded as sample #2.

[0101] Example 3

[0102] Tb(NO3)3(H2O)6 (0.099 mmol), Eu(NO3)3(H2O)6 (0.001 mmol), and terephthalic acid (0.1 mmol) were placed in a 10 mL glass vial in a 1:1 molar ratio, and then DMA (3 ml), water (2 ml), and HCl (0.1 ml) were added. The mixed solution was placed in a sealed container for reaction at a temperature of 100°C for 48 h. After the reaction was completed, the mixture was cooled to room temperature, filtered, washed with DMA and ethanol, and obtained as colorless transparent block crystals [Tb 0.99 Eu 0.01 (BDC) 1.5 (DMA)] n , recorded as sample #3.

[0103] Example 4

[0104] Tb(NO3)3(H2O)6 (0.096 mmol), Eu(NO3)3(H2O)6 (0.004 mmol), and terephthalic acid (0.1 mmol) were placed in a 10 mL glass vial in a 1:1 molar ratio, and then DMA (3 ml), water (2 ml), and HCl (0.1 ml) were added. The mixed solution was placed in a sealed container for reaction at a temperature of 100°C for 48 h. After the reaction was completed, the mixture was cooled to room temperature, filtered, washed with DMA and ethanol, and obtained as colorless transparent block crystals [Tb 0.96 Eu 0.04 (BDC) 1.5 (DMA)] n , recorded as sample #4.

[0105] Example 5

[0106] Tb(NO3)3(H2O)6 (0.094 mmol), Eu(NO3)3(H2O)6 (0.006 mmol), and terephthalic acid (0.1 mmol) were placed in a 10 mL glass vial in a 1:1 molar ratio, and then DMA (3 ml), water (2 ml), and HCl (0.1 ml) were added. The mixed solution was placed in a sealed container for reaction at a temperature of 100°C for 48 h. After the reaction was completed, the mixture was cooled to room temperature, filtered, washed with DMA and ethanol, and obtained as colorless transparent block crystals [Tb 0.94 Eu 0.06 (BDC) 1.5 (DMA)] n , recorded as sample #5.

[0107] Example 6

[0108] Tb(NO3)3(H2O)6 (0.1mmol) and terephthalic acid (0.1mmol) were placed in a 10mL glass vial in a 1:1 molar ratio, and then DMA (3ml), water (2ml), and HBr (0.1ml) solvent were added. The mixed solution was placed in a sealed container for reaction at a temperature of 100°C for 48h. After the reaction was completed, the mixture was cooled to room temperature, filtered, washed with DMA and ethanol, and obtained as colorless transparent block crystals [Tb(BDC) 1.5 (DMA)] n , recorded as sample #6.

[0109] Example 7

[0110] Tb(NO3)3(H2O)6 (0.1mmol) and terephthalic acid (0.1mmol) were placed in a 10mL glass vial in a 1:1 molar ratio, and then DMA (3ml), water (2ml), and HCl (0.1ml) solvent were added. The mixed solution was placed in a sealed container for reaction at a temperature of 120°C for 48h. After the reaction was completed, the mixture was cooled to room temperature, filtered, washed with DMA and ethanol, and obtained as colorless transparent block crystals [Tb(BDC) 1.5 (DMA)] n , recorded as sample #7.

[0111] Example 8

[0112] Tb(CH3COO)3(H2O)6 (0.1mmol) and terephthalic acid (0.1mmol) were placed in a 10mL glass vial in a 1:1 molar ratio, and then DMA (3ml), water (2ml), and HCl (0.1ml) were added. The mixed solution was placed in a sealed container for reaction at a temperature of 100°C for 48h. After the reaction was completed, the mixture was cooled to room temperature, filtered, washed with DMA and ethanol, and obtained as colorless transparent block crystals [Tb(BDC) 1.5 (DMA)] n , recorded as sample #8.

[0113] Example 9

[0114] TbCl3(H2O)6 (0.1mmol) and terephthalic acid (0.1mmol) were placed in a 10mL glass vial in a 1:1 molar ratio, and then DMA (3ml), water (2ml), and HCl (0.1ml) were added. The mixed solution was placed in a sealed container for reaction at a temperature of 100°C for 48h. After the reaction was completed, the mixture was cooled to room temperature, filtered, washed with DMA and ethanol, and obtained as colorless transparent block crystals [Tb(BDC) 1.5 (DMA)] n , recorded as sample #9.

[0115] Example 10

[0116] EuCl3 (0.01 mmol) and terephthalic acid (0.1 mmol) were placed in a 10 mL glass vial in a 1:1 molar ratio, and then DMA (3 ml), water (2 ml), and HCl (0.1 ml) were added. The mixed solution was placed in a sealed container for reaction at a temperature of 100 ° C. and a reaction time of 48 h. After the reaction was completed, the mixture was cooled to room temperature, filtered, washed with DMA and ethanol, and obtained as colorless transparent block crystals [Eu(BDC) 1.5 (DMA)] n, recorded as sample #10.

[0117] Test Example 1[Tb(BDC) 1.5 (DMA)] n Structural characterization of crystalline materials

[0118] The structure of sample #1 prepared in Example 1 was characterized.

[0119] Sample #1[Tb(BDC) 1.5 (DMA)] n X-ray single crystal diffraction was performed on a Rigaku FR-X single crystal diffractometer (test conditions: Mo target, K α Radiation source (λ=0.07107nm, test temperature 293K), after passing through Olex 2 1.5 Analyze the structure.

[0120] The X-ray single crystal diffraction analysis results show that the crystalline material structure of sample #1 is [Tb(BDC) 1.5 (DMA)] n , belongs to the monoclinic P-1 space group. The unit cell parameters are α=93.377(4)°, β=114.480(4)°, γ=116.935(6)°, Z=1,

[0121] Crystal material of sample #1 [Tb(BDC) 1.5 (DMA)] n The coordination environment diagram is shown in the attached Figure 1 As shown, the minimum asymmetric structural unit contains 1 Tb 3+ Metal ions, 1.5 BDC 2- ligand and one coordinated DMA molecule.

[0122] Tb 3+ The metal ion is coordinated with 8 oxygen atoms, which are respectively from 4 BDC 2- There are 7 O atoms on the carboxylate group of the ligand and 1 O atom from the coordinated DMA molecule.

[0123] The X-ray powder diffraction spectrum of sample #1 is shown in the attached figure. Figure 2 As shown, the experimental results (1 represents sample #1) are consistent with the simulation results (simulation line), indicating that the material is pure phase, that is, Tb-based rare earth scintillating material [Tb(BDC) 1.5 (DMA)] n .

[0124] Samples #6, #7, #8, and #9 were tested using the same method as above. The X-ray single crystal diffraction analysis results of samples #6, #7, #8, and #9 were consistent with those of sample #1; the XRD test results of samples #6, #7, #8, and #9 were consistent with those of sample #1.

[0125] Test Example 2[Tb(BDC) 1.5 (DMA)] n Photoluminescence performance test of crystal materials

[0126] The photoluminescence performance of sample #1 prepared in Example 1 was tested.

[0127] Sample #1[Tb(BDC) 1.5 (DMA)] n The photoluminescence performance of the crystal material was tested on Edinburgh FL1000. The excitation and emission spectra are shown in the attached figure. Figure 3 As shown, under the excitation of the optimal wavelength of 308nm, the compound exhibits green light emission at 488, 542, 582 and 620nm. The RGB color coordinates of the blue light emitting crystal material are calculated to be (0.300, 0.621) (as shown in FIG. Figure 4 ). Figure 5 It can be seen that the photoluminescence quantum yield (PLQY) of sample 1 is as high as 83.80%, which is unusual in rare earth complexes.

[0128] The luminescence lifetime was tested using the Edinburgh FL1000 microsecond lamp and PMT detector. The luminescence lifetime and fitting curve are shown in the attached figure. Figure 6 As shown, the luminescence lifetime test shows that sample #1[Tb(BDC) 1.5 (DMA)] n The lifetime of the crystal material is 1.405ms, which is in the ms level.

[0129] Samples #6, #7, #8, and #9 were tested using the same method as above. The photoluminescence performance test results of samples #6, #7, #8, and #9 were consistent with those of sample #1.

[0130] Test Example 3[Tb(BDC) 1.5 (DMA)] n Scintillation luminescence and X-ray imaging performance testing of crystal materials

[0131] The scintillation luminescence performance of sample #1 prepared in Example 1 was tested.

[0132] Sample #1[Tb(BDC) 1.5 (DMA)] nThe scintillation luminescence test of crystal materials is carried out on an X-ray scintillation spectrometer. The main part of the instrument is the X-ray scintillation spectrometer, in which the excitation source is a high-purity tungsten target (model: MAGPRO X-ray sources). The scintillation spectrum is shown in the attached figure. Figure 7 Under X-ray irradiation with constant tube voltage and different tube current, the compound showed scintillation signals at 488, 542, 582 and 620 nm. The scintillation luminescence performance of sample 1 was characterized, and the scintillation intensity of sample 1 was much higher than that of commercial scintillators LYSO:Ce and BGO (such as Figure 7 The linear spectrum of scintillation luminescence intensity and X-ray dose is shown in the attached figure. Figure 8 , with the increase of X-ray dose, the scintillation signal intensity increases linearly, and has a higher response sensitivity to X-rays. In addition, Figure 9 The detection limit of the characterized sample 1 was 73.1 nGy / s, which is about 75 times lower than the detection limit of 5.5 μGy / s required for commercial medical diagnosis.

[0133] Samples #6, #7, #8, and #9 were tested using the same method as above. The scintillation luminescence performance test results of samples #6, #7, #8, and #9 were consistent with those of sample #1.

[0134] Test Example 4[Tb(BDC) 1.5 (DMA)] n Stability testing of crystal materials

[0135] Thermogravimetric analysis of sample 1 showed the following results: Figure 10 As shown. Figure 10 It can be seen that sample 1 remains stable below about 258°C, showing excellent thermal stability.

[0136] The irradiation stability test was conducted on the sample #1 prepared in Example 1. Under at least 3 hours of continuous X-ray irradiation (irradiation conditions: X-ray tube voltage 50kV, X-ray dose rate 42.29mGy / s), the scintillation performance of sample 1 did not significantly decrease (due to Figure 11 visible).

[0137] Samples #6, #7, #8, and #9 were tested using the same method as above. The radiation stability test results of samples #6, #7, #8, and #9 were consistent with those of sample #1.

[0138] The above descriptions are merely several embodiments of the present invention and do not constitute any form of limitation to the present invention. Although the present invention is disclosed as above in terms of preferred embodiments, they are not intended to limit the present invention. Any technician familiar with the present profession who, without departing from the scope of the technical solution of the present invention, makes slight changes or modifications using the technical contents disclosed above are equivalent to equivalent implementation cases and fall within the scope of the technical solution.

[0139] Test Example 5 [Eu(BDC) 1.5 (DMA)] n Photoluminescence performance test of crystal materials

[0140] The X-ray powder diffraction spectrum of sample #2 is shown in the attached figure. Figure 12 As shown, the experimental results are consistent with the simulation results (simulation line), indicating that the material is a pure phase, that is, Eu-based rare earth scintillating material [Eu(BDC) 1.5 (DMA)] n .

[0141] The photoluminescence performance of sample #2 prepared in Example 2 was tested.

[0142] Sample #2 [Eu(BDC) 1.5 (DMA)] n The photoluminescence performance of the crystalline materials was tested on an Edinburgh FL1000.

[0143] Excitation and emission spectra are shown in the attached Figure 13 As shown, under the excitation of the optimal wavelength of 300nm, the compound exhibits red light emission at 589, 612, 652 and 700nm. The RGB color coordinates of the red light-emitting crystal material are calculated to be (0.655, 0.336) (as shown in FIG. Figure 14 ). Figure 15 It can be seen that the photoluminescence quantum yield (PLQY) of sample 2 is as high as 67.96%.

[0144] The luminescence lifetime was tested using the Edinburgh FL1000 microsecond lamp and PMT detector. The luminescence lifetime and fitting curve are shown in the attached figure. Figure 16 As shown, the luminescence lifetime test shows that sample #1 [Eu(BDC) 1.5 (DMA)] n The lifetime of the crystal material is 1.293ms, which is in the ms level.

[0145] Sample #10 was tested using the same method as above. The photoluminescence performance test results of sample #10 were consistent with those of sample #2.

[0146] Test Example 6 [Eu(BDC) 1.5 (DMA)] n Scintillation luminescence and X-ray imaging performance testing of crystal materials

[0147] The scintillation luminescence performance of sample #2 prepared in Example 2 was tested.

[0148] Sample #2 [Eu(BDC) 1.5(DMA)] n The scintillation luminescence test of the crystal material was carried out on an X-ray scintillation spectrometer. The main part of the instrument is an Edinburgh FLS1000 fluorescence spectrometer, in which the excitation source is a high-purity tungsten target (model: MAGPRO X-ray sources). The scintillation spectrum is shown in the attached figure. Figure 7 Under X-ray irradiation with constant tube voltage and different tube current, the compound showed scintillation signals at 589, 612, 652 and 700 nm. The linear spectrum of scintillation luminescence intensity versus X-ray dose is shown in the attached figure. Figure 17 , with the increase of X-ray dose, the scintillation signal intensity increases linearly. In addition, Figure 18 The detection limit of characterized sample 2 is 0.67 μGy / s, which is lower than the detection limit of 5.5 μGy / s required for commercial medical diagnosis.

[0149] Sample #10 was tested using the same method as above. The scintillation performance test results of sample #10 were consistent with those of sample #2.

[0150] Test Example 7 [Eu(BDC) 1.5 (DMA)] n Stability testing of crystal materials

[0151] The radiation stability test was performed on sample #2 prepared in Example 2.

[0152] For #2[Eu(BDC) 1.5 (DMA)] n Thermogravimetric analysis of the crystal material was performed, and the results were as follows Figure 19 As shown. Figure 19 It can be seen that sample 2 remains stable below about 276°C, showing excellent thermal stability.

[0153] Sample #2 [Eu(BDC) 1.5 (DMA)] n The irradiation stability test of the crystal material is carried out on an X-ray scintillation spectrometer. The sample is irradiated under continuous high dose rate X-rays and its luminescence intensity is recorded, such as Figure 11 As shown, under at least 3 hours of continuous X-ray irradiation (irradiation conditions: X-ray tube voltage 50 kV, X-ray dose rate 42.29 mGy / s), the scintillation performance of sample 1 does not decrease significantly, which shows that it has good irradiation stability.

[0154] Sample #10 was tested using the same method as above. The radiation stability test results of sample #10 were consistent with those of sample #2.

[0155] The above descriptions are merely a few embodiments of the present application and do not constitute any form of limitation to the present application. Although the present application discloses the preferred embodiments as above, they are not intended to limit the present application. Any technical personnel familiar with the present profession, without departing from the scope of the technical solution of the present application, using the technical content disclosed above to make slight changes or modifications are equivalent to equivalent implementation cases and fall within the scope of the technical solution.

Claims

1. A multi-color rare earth scintillation crystal, characterized in that: The chemical formula of the multi-color rare earth scintillation crystal is [Ln(BDC) 1.5 (DMA)] n ; Among them, Ln is the rare earth ion Tb 3+ and / or Eu 3+ , BDC is deprotonated terephthalic acid, DMA is N,N-dimethylacetamide; n is ∞, which means it will be repeated and extended infinitely.

2. The multi-color rare earth scintillation crystal according to claim 1, characterized in that: When Ln is rare earth ion Tb 3+ and Eu 3+ When Eu 3+ The proportion is 0.5% to 15%.

3. The multi-color rare earth scintillation crystal according to claim 1, characterized in that: The multi-color rare earth scintillation crystal is a three-dimensional framework structure, and its minimum asymmetric structural unit contains 1.5 BDC 2- Ligand, 1 Ln 3+ Metal ions, 1 DMA molecule; Ln 3+ The metal ion is Tb in an octa-coordinate configuration. 3+ / Eu 3+ Metal ions; Ln 3+ Metal ions are respectively combined with the four BDC 2- Seven O atoms on the carboxylate group of the ligand and one O atom on DMA are coordinated.

4. The multi-color rare earth scintillation crystal according to claim 1, characterized in that: The multi-color rare earth scintillating crystal belongs to the triclinic system and has a P-1 space group structure; The unit cell parameters of the crystal are: α=93~94°, β=114~115°, γ=116~118°; Preferably, α=93.1~93.5°, β=114.1~114.7°, γ=116.5~117.2°.

5. The method for preparing the multi-color rare earth scintillation crystal according to any one of claims 1 to 4, characterized in that: placing a mixed solution containing terephthalic acid, a Ln metal source, and a solvent in a sealed container for reaction to obtain the multi-color rare earth scintillation crystal; The solvent includes N,N-dimethylacetamide and hydrogen halide, and at least one of water, methanol and ethanol.

6. The preparation method according to claim 5, characterized in that The Ln metal source is selected from at least one of nitrates, acetates, and chlorides corresponding to Tb and Eu; The hydrogen halide is selected from at least one of HCl and HBr.

7. The preparation method according to claim 5, characterized in that The molar ratio of terephthalic acid to Ln metal source is 1:1 to 1:2; The molar amount of the Ln metal source is calculated based on the molar amount of the Ln element in the metal source.

8. The preparation method according to claim 5, characterized in that The molar volume ratio of the Ln metal source to N,N-dimethylacetamide is 0.1 mmol:3-5 mL.

9. The preparation method according to claim 5, characterized in that The reaction temperature is 80 to 140° C., and the reaction time is 24 to 72 hours; Preferably, the reaction temperature is 90-120° C., and the reaction time is 36-54 hours.

10. Use of the multi-color rare earth scintillation crystal according to any one of claims 1 to 4 in multi-color fluorescent materials, light-emitting diodes, X-ray detection materials, radiation detection dosimeters, and radiation imaging devices.

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