Terbium complex luminescent scintillation material, synthesis method and application thereof

Abstract

This invention discloses a terbium complex luminescent scintillation material, its synthesis method, and its applications. The terbium complex is synthesized using a β-diketone bidentate chelating ligand and a bromine-substituted organophosphorus oxide monodentate ligand with Tb. 3+ The ions form an isolated mononuclear structure with an eight-coordinate configuration. The chemical composition of the terbium complex luminescent scintillation material is [Tb(hfac)3·((3-BrPh)3PO)2]; wherein, hfac ‑ It is the hexafluoroacetylacetonate ion (C5HF6O2) ‑ (3-BrPh)3PO is tris(3-bromophenyl)phosphine oxide. This material exhibits good stability and excellent photoluminescence and scintillation properties, with its scintillation spectral intensity far exceeding that of commercially available scintillation crystals (BGO). Therefore, this material has potential application value in the fabrication of organic light-emitting devices, scintillation detectors, and radiation imaging devices.

Description

Technical Field

[0001] This invention relates to a terbium complex luminescent scintillation material, its preparation method and application, belonging to the technical field of luminescent and scintillation materials. Background Technology

[0002] Scintillation materials are a class of functional materials that can convert high-energy rays or particles such as X-rays and gamma rays into ultraviolet-visible light. They are widely used in key fields such as medical imaging diagnosis, industrial non-destructive testing, public safety inspection, and nuclear radiation monitoring. Rare earth metal terbium ions have unique 4f electron transition characteristics and often exhibit advantages such as narrow-band strong fluorescence emission, long luminescence lifetime, and high quantum yield, making them an ideal metal center for constructing high-performance luminescent scintillation materials. The terbium complex luminescent scintillation materials reported in the prior art still have some shortcomings: (1) the ligand energy transfer efficiency of some complexes is low, resulting in low luminescence intensity and insufficient scintillation sensitivity; (2) the thermal and chemical stability of some complexes is poor, and they are easily decomposed in high-temperature and humid environments, affecting their long-term use; (3) the solubility of some complexes is poor, making it difficult to prepare them into practical forms such as thin films and powders, which limits their application in fields such as flexible imaging and device integration; (4) the X-ray absorption capacity of existing complexes is limited, and the response performance in high-energy ray detection scenarios needs to be improved. To address the above problems, in this invention, hexafluoroacetylacetone (Hhfac) and tris(3-bromophenyl)phosphine trioxide ((3-BrPh)3PO) were specifically selected as dual ligands to construct mononuclear terbium complexes for the following reasons: (1) Hexafluoroacetylacetone (Hhfac), as a typical β-diketone ligand, has a trifluoromethyl group (-CF3) in its molecular structure that has strong electron-withdrawing properties. This not only enhances the ultraviolet absorption intensity of the ligand but also reduces the triplet energy level of the ligand, making it more compatible with Tb. 3+ The excited state energy levels of the ions are well matched, thereby significantly improving the energy transfer efficiency; (2) The tris(3-bromophenyl)phosphine oxide ((3-BrPh)3PO) ligand has excellent sensitization ability and can also interact with Tb through the oxygen atom in the phosphine-oxygen double bond (P=O). 3+ Ion coordination forms a stable eight-coordinate structure. Simultaneously, the bromine atom can lower the triplet energy level of the phosphooxy ligand, enabling it to react with Tb. 3+ The excited-state energy levels of the ions are well matched, further optimizing the luminescence performance of the complex. The terbium complex luminescent scintillation material in this application exhibits good air stability, water stability, and thermal stability; it also possesses excellent photoluminescence and scintillation luminescence properties: it emits bright green light under ultraviolet light irradiation, and the maximum luminescence intensity in its scintillation spectrum is much higher than the maximum luminescence intensity of commercial scintillation crystal BGO; it also has good solubility in some polar organic solvents, and good film-forming properties when fabricating devices. Summary of the Invention

[0003] The purpose of this invention is to provide a terbium complex luminescent scintillation material, its preparation method, and its applications. The material exhibits good stability, high luminous efficiency, high scintillation sensitivity, and good solubility. This invention also provides a simple and efficient preparation method for the material, as well as its applications in related fields.

[0004] According to one aspect of this application, a terbium complex luminescent scintillating material is provided.

[0005] The chemical formula of the terbium complex luminescent scintillation material is: [Tb(hfac)3·((3-BrPh)3PO)2], where hfac - It is the hexafluoroacetylacetonate ion (C5HF6O2) - (3-BrPh)3PO is tris(3-bromophenyl)phosphine oxide. The coordination structure of the terbium complex scintillation material is as follows: six oxygen atoms from three hexafluoroacetylacetonate ions and two oxygen atoms from two tris(3-bromophenyl)phosphine oxide molecules are associated with Tb. 3+ Ion coordination forms an octagonal mononuclear isolated structure.

[0006] Optionally, the crystal structure of the terbium complex luminescent scintillation material belongs to the orthorhombic crystal system and has the following characteristics: P na21 space group structure.

[0007] Optionally, in the unit cell parameters of the terbium complex luminescent scintillation material, a = 23.68~23.88 Å, b =11.74~11.94 Å, c = 21.18~21.38 Å; Preferably, in the terbium complex luminescent scintillation material, the unit cell parameters are as follows: a = 23.7947(3) Å, b =11.8411(2) Å, c = 21.2844(3) Å; Optionally, in the unit cell parameters of the terbium complex luminescent scintillation material, a = 89.8~90.8°, b = 89.8~90.8°, g = 89.8~90.8°, V = 5995~6005 Å 3 ; Preferably, in the terbium complex luminescent scintillation material, the unit cell parameters are as follows: a = 90°, b = 90°, g = 90°, V= 5997.00(15) Å 3 .

[0008] Optionally, the terbium complex luminescent scintillation material exhibits strong characteristic emission of terbium complexes under ultraviolet-visible light or X-ray excitation at wavelengths of 280-400 nm.

[0009] Optionally, the material exhibits Tb values ​​near 489 nm, 545 nm, 580 nm, and 619 nm at an excitation wavelength of 280–400 nm. 3+ The characteristic emission peak of the ions results in an overall emission light color of green.

[0010] Optionally, the material exhibits Tb values ​​near 490 nm, 545 nm, 582 nm, and 620 nm when excited by X-rays. 3+ The characteristic emission peaks of the ions are shown, with the strongest emission peak at 545 nm, which is 24 to 26 times the intensity of the X-ray emission peak of the BGO scintillator, specifically 25.2 times.

[0011] Optionally, the luminescence lifetime of the terbium complex luminescent scintillator material is 390~410 μs.

[0012] Specifically, the luminescence lifetime of the terbium complex luminescent scintillator material is 399.6 μs.

[0013] Optionally, the luminescence quantum yield of the terbium complex luminescent scintillation material is 31-32%.

[0014] Specifically, the luminescence quantum yield of the terbium complex luminescent scintillation material is 31.6%.

[0015] According to another aspect of this application, a method for preparing the terbium complex luminescent scintillation material described above is provided.

[0016] Method 1: Solvent thermal synthesis (1) Weigh out terbium salt, hexafluoroacetylacetone and tris(3-bromophenyl)phosphine oxide, and dissolve them in an organic solvent; (2) Place it in a hydrothermal reactor and keep it at a constant temperature of 70-160℃ for 1-5 days; (3) After naturally cooling to room temperature, the terbium complex luminescent scintillating material crystals can be obtained by naturally evaporating in a fume hood for 2 to 5 days.

[0017] Method 2: Solution Method (1) Weigh terbium salt, hexafluoroacetylacetone and tris(3-bromophenyl)phosphine oxide, dissolve them in an organic solvent, and stir magnetically at 40~80℃ for 1~2 hours to obtain a clear solution; (2) The above solution is placed in a fume hood and allowed to evaporate naturally for several days to obtain the terbium complex luminescent material.

[0018] Optionally, the terbium salt is selected from at least one of TbCl3, TbBr3, Tb(ClO4)3, Tb(CH3COO)3, Tb(NO3)3, and Tb2(SO4)3.

[0019] Optionally, the organic solvent is selected from at least one of polar organic solvents such as methanol, ethanol, propanol, ethylene glycol, N,N-dimethylformamide, N,N-dimethylacetamide, acetone, dichloromethane, chloroform, tetrahydrofuran, 1,4-epoxyhexanes and acetonitrile.

[0020] Optionally, in step (1) of methods one and two, the molar ratio of terbium salt, hexafluoroacetylacetone and tris(3-bromophenyl)phosphine oxide is 1:(2.5~3.5):(1.5~2.5).

[0021] Optionally, the conditions for Method 1 are: temperature of 70~160℃ and time of 1-5 days.

[0022] Optionally, the conditions for Method 2 are: temperature of 40~80℃, time of 1-3 hours, until the solution becomes clear.

[0023] As a preferred embodiment, the method for preparing the terbium complex luminescent scintillation material includes: The terbium complex luminescent scintillator material is prepared by placing TbCl3·6H2O, hexafluoroacetylacetone, and tri(3-bromophenyl)phosphine oxide in a 20 mL glass bottle at a molar ratio of 1:3:2. Ethanol is then added, and the mixture is heated and stirred at 50 °C until the solution becomes clear. Finally, the solution is left to evaporate naturally in a fume hood for 3-5 days to obtain the green blocky crystals of the terbium complex luminescent scintillator material.

[0024] According to another aspect of this application, the application of the terbium complex luminescent scintillation material is provided. This terbium complex luminescent scintillation material exhibits strong green luminescence under ultraviolet-visible light and X-ray irradiation in the wavelength range of 280–400 nm.

[0025] The above-described terbium complex luminescent scintillation materials and / or terbium complex luminescent scintillation materials prepared by the above-described preparation method are used in the fields of luminescent materials, high-energy radiation detection materials, radiation detection dosimeters, radiation imaging devices, medical imaging, public safety inspection, nuclear radiation monitoring, flexible light-emitting devices, or fluorescence sensing.

[0026] The beneficial effects that this application can produce include: (1) The material provided in this application has excellent luminescence and scintillation properties: The present invention uses hexafluoroacetylacetone (Hhfac) and tris(3-bromophenyl)phosphine oxide as ligands. Their suitable triplet energy levels can efficiently absorb external energy and transfer it to Tb.3+ Ions, and organophosphorus oxide ligands for Tb 3+ The stable coordination of ions effectively suppresses nonradiative transitions, resulting in high efficiency of the complex. Its X-ray scintillation sensitivity is far higher than that of commercial BGO scintillators, and its luminescence lifetime is appropriate (399.6 μs), which can meet the requirements of high-performance detection.

[0027] (2) The terbium complex luminescent scintillation material provided in this application has good stability: Tb 3+ Ions and HFAC - The ligand and tris(3-bromophenyl)phosphine oxide ligand form a stable eight-coordinate isolated mononuclear structure. The thermal decomposition temperature of the complex is higher than 250℃. It is not easily decomposed in high temperature and humid environment, and has excellent chemical stability, which can be used stably for a long time. At the same time, the complex has good solubility in common organic solvents, which makes it easy to prepare into various practical forms such as thin films, powders, and crystals, thus broadening its application scenarios.

[0028] (3) The preparation method of the terbium complex luminescent scintillation material provided in this application is simple and efficient, and the raw materials are readily available, making it suitable for large-scale production. At the same time, the terbium complex luminescent scintillation material provided in this application has both excellent luminescence and scintillation properties, and can be widely used in fields such as light-emitting devices and fluorescence sensing, high-energy ray detection, medical imaging, public safety inspection, and nuclear radiation monitoring. It has unique advantages in the field of flexible X-ray imaging, and can realize high-definition imaging of non-planar objects. Attached Figure Description

[0029] Figure 1 These are comparison images of the crystalline material [Tb(hfac)3·((3-BrPh)3PO)2] under X-ray and ultraviolet light excitation, respectively. Figure 2 This is a schematic diagram of the coordination environment of the crystalline material [Tb(hfac)3·((3-BrPh)3PO)2]; Figure 3 This is a thermogravimetric analysis curve of the crystalline material [Tb(hfac)3·((3-BrPh)3PO)2]; Figure 4 This is the photoluminescence spectrum of the crystalline material [Tb(hfac)3·((3-BrPh)3PO)2]; Figure 5 This is the fluorescence lifetime spectrum of the crystalline material [Tb(hfac)3·((3-BrPh)3PO)2]; Figure 6 These are the scintillation emission spectra of the crystalline materials [Tb(hfac)3·((3-BrPh)3PO)2] and BGO; Figure 7It is a linear spectrum of the scintillation emission intensity of the crystalline materials [Tb(hfac)3·((3-BrPh)3PO)2] and BGO as a function of X-ray dose; Figure 8 It is the scintillation detection limit diagram of the crystalline material [Tb(hfac)3·((3-BrPh)3PO)2] and BGO; Figure 9 This is a radiation stability diagram of the crystalline material [Tb(hfac)3·((3-BrPh)3PO)2] at a dose rate of 42.29 uGy / s. Detailed Implementation

[0030] It should be understood that the above general description and the following detailed description are merely exemplary and do not limit this disclosure. The invention will now be described in further detail through specific embodiments and in conjunction with the accompanying drawings.

[0031] Example 1: Preparation of the crystal material [Tb(hfac)3·((3-BrPh)3PO)2] 0.5 mmol TbCl3·6H2O, 1.5 mmol hexafluoroacetylacetone and 1 mmol tris(3-bromophenyl)phosphine oxide were placed in a 20 mL glass bottle, 8 mL of ethanol was added, and the mixture was magnetically stirred at 50 °C until the solution became clear. Then it was placed in a fume hood for several days, and light green blocky crystals [Tb(hfac)3·((3-BrPh)3PO)2] were formed, with a yield of about 80% (calculated based on TbCl3·6H2O).

[0032] Example 2: Characterization of the structural thermal stability of the crystalline material [Tb(hfac)3·((3-BrPh)3PO)2] The crystalline material prepared in Example 1 was characterized structurally. X-ray single-crystal diffraction tests were performed on a Rigaku FR-X single-crystal diffractometer with a Mo target. K alpha radiation source ( λ = 0.07107 nm), tested at 293 K. The structure was analyzed using Olex2.

[0033] X-ray single-crystal diffraction results indicate that the crystalline material has the structural formula [Tb(hfac)3·((3-BrPh)3PO)2], belonging to the cubic crystal system. P Space group na21. Cell parameters are: a = 23.7947(3) Å, b = 11.8411(2) Å, c =21.2844(3) Å; a = 90°, b= 90°, g = 90°, V = 5997.00(15) Å 3 A schematic diagram of the coordination environment of the crystalline material [Tb(hfac)3·DPEPO] is shown below. Figure 2 As shown, three hexafluoroacetylacetone molecules provide a total of six coordinated oxygen atoms, and two tris(3-bromophenyl)phosphine oxide molecules provide two coordinated oxygen atoms, while simultaneously reacting with Tb. 3+ Ion coordination forms an isolated mononuclear structure with eight coordination groups. The crystalline material [Tb(hfac)3·((3-BrPh)3PO)2] is soluble in polar organic solvents but insoluble in water, and exhibits good thermal stability, such as... Figure 3 As shown in the thermogravimetric analysis curve, its thermal stability is as high as 250℃ or more, which can meet the thermal stability requirements of general devices.

[0034] Example 3: Photoluminescence performance test of crystal material [Tb(hfac)3·((3-BrPh)3PO)2] The photoluminescence properties of the crystalline material [Tb(hfac)3·((3-BrPh)3PO)2] were tested using an Edinburgh F920 fluorescence spectrometer. The excitation and emission spectra are shown below. Figure 4 As shown, this material exhibits Tb values ​​near 489 nm, 545 nm, 580 nm, and 619 nm. 3+ The characteristic emission peak of the ions results in an overall green emission color. The luminescence lifetime was measured using a μF 900 microsecond lamp and a PMT detector; the luminescence lifetime and fitting curve are shown below. Figure 5 As shown, its luminescence lifetime is 399.6 μs. At a test temperature of 298 K, the luminescence efficiency was measured on an FLS920 fluorescence spectrometer equipped with an R928P PMT detector and an integrating sphere, and its quantum yield reached 31.6%.

[0035] Example 4: Scintillation luminescence performance test of crystal material [Tb(hfac)3·((3-BrPh)3PO)2] The scintillation emission of the crystalline material [Tb(hfac)3·((3-BrPh)3PO)2] was measured using an X-ray scintillation spectrometer. The main instrument was an Edinburgh FLS 920 fluorescence spectrometer, in which the excitation source was replaced by a high-purity tungsten target (Moxtek® MAGPRO X-ray sources) instead of a Xe lamp. The scintillation emission spectrum is shown below. Figure 6Under X-ray irradiation with a tube voltage of 50V and a tube current of 100uA, the crystalline material [Tb(hfac)3·((3-BrPh)3PO)2] exhibited characteristic emission signals of terbium near 490nm, 545nm, 582nm, and 620nm, with the highest emission peak intensity at 545nm, which was 25.2 times that of the commercial scintillator BGO. The linear spectrum of scintillation intensity with X-ray dose is shown below. Figure 7 As the X-ray dose increases, the scintillation signal intensity shows a linear increasing trend. For example... Figure 8 As shown, the scintillation detection limit of the crystalline material [Tb(hfac)3·((3-BrPh)3PO)2] is lower than that of the commercially available scintillation material BGO, being only 0.263 times the detection limit of BGO. Figure 9 As shown, after continuous X-ray irradiation at a dose rate of 42.29 uGy / s for 3600 s, the luminescence intensity of the crystal material [Tb(hfac)3·((3-BrPh)3PO)2] at 545 nm remained at 95.8%.

[0036] The above description is merely a few embodiments of this application and is not intended to limit this application in any way. Although this application discloses preferred embodiments as described above, it is not intended to limit this application. Any changes or modifications made by those skilled in the art without departing from the scope of the technical solution of this application using the disclosed technical content are equivalent to equivalent implementation cases and fall within the scope of the technical solution.

Claims

1. A terbium complex luminescent scintillation material constructed from hexafluoroacetylacetone and tris(3-bromophenyl)phosphine oxide ligand, characterized in that: The molecular formula of this terbium complex luminescent scintillation material is: [Tb(hfac)3·((3-BrPh)3PO)2], where hfac - It is the hexafluoroacetylacetonate ion C5HF6O2 - (3-BrPh)3PO is tris(3-bromophenyl)phosphine oxide, and this terbium complex luminescent and scintillating material has green luminescence and scintillating properties.

2. The terbium complex luminescent scintillation material according to claim 1, characterized in that: The terbium complex luminescent scintillation material is characterized by an isolated mononuclear structure with an octetal coordination configuration.

3. The terbium complex luminescent scintillation material according to claim 1 or 2, characterized in that, The material exhibits Tb values ​​near 489 nm, 545 nm, 580 nm, and 619 nm when excited at wavelengths of 280–400 nm. 3+ The characteristic emission peak of the ions results in an overall emission light color of green.

4. The terbium complex luminescent scintillation material according to claim 1 or 2, characterized in that, The luminescence lifetime of the material is 390~410 μs.

5. The terbium complex luminescent scintillation material according to claim 1 or 2, characterized in that, The material exhibits Tb near 490 nm, 545 nm, 582 nm, and 620 nm when excited by X-rays. 3+ The characteristic emission peaks of the ions are observed, with the strongest emission peak at 545 nm, which is 24 to 26 times the intensity of the X-ray emission peak of the BGO scintillator.

6. The method for preparing the terbium complex luminescent scintillation material according to claim 1 or 2, characterized in that: Synthesized using solvothermal synthesis or solution synthesis: Method 1: Solvent thermal synthesis (1) Weigh out terbium salt, hexafluoroacetylacetone and tris(3-bromophenyl)phosphine oxide, and dissolve them in an organic solvent; (2) Place it in a hydrothermal reactor and keep it at a constant temperature of 70-160℃ for 1-5 days; (3) After naturally cooling to room temperature, allow it to evaporate naturally in a fume hood for 2-5 days to obtain the crystal of the terbium complex luminescent scintillating material; Method 2: Solution Method (1) Weigh terbium salt, hexafluoroacetylacetone and tris(3-bromophenyl)phosphine oxide, dissolve them in an organic solvent, and stir magnetically at 40~80℃ for 1~3 hours to obtain a clear solution; (2) The crystals of the terbium complex luminescent scintillation material are obtained by placing the above-mentioned clear solution in a fume hood and allowing it to evaporate naturally for several days.

7. The preparation method according to claim 6, characterized in that, The terbium salt in step (1) of methods one and two is selected from at least one of the following anhydrous or hydrated terbium salts: TbCl3, TbBr3, Tb(ClO4)3, Tb(CH3COO)3, Tb(NO3)3, and Tb2(SO4)3; the organic solvent is selected from at least one of methanol, ethanol, propanol, ethylene glycol, N,N-dimethylformamide, N,N-dimethylacetamide, acetone, dichloromethane, chloroform, tetrahydrofuran, 1,4-epoxyhexanes, and acetonitrile.

8. The preparation method according to claim 6, characterized in that, In step (1) of methods one and two, the molar ratio of terbium salt, hexafluoroacetylacetone and tris(3-bromophenyl)phosphine oxide is 1:(2.5~3.5):(1.5~2.5).

9. The application of the terbium complex luminescent scintillation material according to claim 1 or 2 and / or the terbium complex luminescent scintillation material prepared by the preparation method according to any one of claims 6 to 8 in green luminescent materials, organic light-emitting device preparation, high-energy ray radiation detection materials, radiation detection dosimeters, and radiation imaging devices.

Images