Manganese-based organic-inorganic hybrid metal halide, scintillator film and preparation method thereof

Abstract

The invention belongs to the field of hybrid metal halide scintillator materials, and discloses a manganese-based organic-inorganic hybrid metal halide, a scintillator film and a preparation method thereof. The structural formula of the manganese-based organic-inorganic hybrid metal halide is (C33H29NP) xMnXy.zL, in the structural formula, X is one or more of F, Cl, Br and I, 0 lt; x is less than or equal to 2, 0lt; y is smaller than or equal to 4, L is one or more of C2H6O, CH4O, CH2Cl2 and H2O, and z is larger than or equal to 0. The manganese-based organic-inorganic hybrid metal halide scintillator has the advantages of simple synthesis, low cost, environmental friendliness, excellent luminescence performance and the like, and can be effectively excited by ultraviolet light and high-energy X rays. After the scintillator material is prepared into a flexible film, clear imaging under X-rays can be realized, and the scintillator material has certain application potential in the field of medical X-ray imaging and the field of safety inspection.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of hybrid metal halide scintillator materials, and relates to a manganese-based organic-inorganic hybrid metal halide, a scintillator thin film and a preparation method thereof. BACKGROUND

[0002] X-ray detection technology, as one of the core means of modern scientific research and industrial application, plays a vital role in the fields of medical imaging, non-destructive testing, security and safety inspection, space exploration, etc. Since the discovery of X-rays by Roentgen in 1895, its detection technology has undergone iterative development from gas ionization detectors to semiconductor detectors, and then to scintillator detectors. Among them, scintillator detectors have become the mainstream technology route for high-energy radiation detection due to their high sensitivity, wide dynamic range, and imaging capability. Traditional inorganic X-ray scintillators, such as cesium iodide single crystal (CsI: Tl) and sodium iodide single crystal (NaI: Tl), have been successfully developed and commercialized due to their high light yield and excellent stability under X-ray irradiation. However, with the increasing demand for detector performance in modern application scenarios, such as low-dose imaging, high resolution, flexibility, and low-cost manufacturing, the limitations of traditional scintillator materials have become increasingly apparent, and breakthroughs are urgently needed through material innovation and technological innovation.

[0003] In recent years, metal halides represented by lead halide have become a promising X-ray scintillator due to their high X-ray absorption coefficient, easy solution processing, and high scintillation light yield. However, these materials, despite their good performance, are severely limited in their potential commercial applications due to the toxicity of lead.

[0004] Low-toxicity lead-free organic-inorganic hybrid metal halide materials combine the excellent properties of organic and inorganic components, have a unique "host-guest" structure and rich physical and chemical properties, and currently exhibit broad application prospects in photovoltaic solar cells, solid-state lighting, displays, medical and security applications of X-ray scintillators, etc. Among them, environmentally friendly manganese-based organic-inorganic hybrid metal halides have inherent advantages such as low toxicity, excellent air stability, structural tunability, and absorption of X-rays by heavy atoms (metals and halides), and due to the charge balance with organic cations, large organic molecules will [MnX4] 2-The separation to form a 0D "host-guest" structure endows it with negligible self-absorption, high photoluminescence quantum yield (PLQY), high scintillation rate, and low detection limit, making it a promising candidate material for X-ray imaging applications (Xu L-J, Lin X, He Q, et al. Highly efficient eco-friendly X-ray scintillators based on an organic manganese halide [J]. Nature Communications, 2020, 11(1): 4329.). However, most of the current manganese-based organic-inorganic hybrid metal halides have poor stability and low light yield, which limits their application in the field of X-ray detection. Therefore, there is an urgent need to develop a scintillator with high stability for high-resolution X-ray imaging. Summary of the Invention

[0005] The purpose of the present invention is to overcome the deficiencies of the prior art and propose a manganese-based organic-inorganic hybrid metal halide, a scintillator film, and a preparation method thereof. The scintillator of the present invention has high irradiation stability and high light yield. The prepared scintillator film has good flexibility and can achieve high-resolution X-ray imaging.

[0006] The purpose of the present invention is achieved through the following technical solutions: In the first aspect, the present invention provides a manganese-based organic-inorganic hybrid metal halide with a chemical composition of (C 33 H 29 NP) x MnX y ·zL, where X is one or more of F, Cl, Br, I, 0 < x ≤ 2, 0 < y ≤ 4, L is one or more of C2H6O, CH4O, CH2Cl2, H2O, and z ≥ 0.

[0007] Preferably, the manganese-based organic-inorganic hybrid metal halide is prepared by a slow solvent evaporation method, and X therein is one or more of F, Cl, Br, I.

[0008] In the second aspect, the present invention provides a preparation method for a manganese-based organic-inorganic hybrid metal halide, including the following steps: S1 Under alkaline conditions, carbazole undergoes a mononuclear nucleophilic substitution reaction with X(CH2)3X to generate C 15 H 14 XN; S2 Mix the C 15 H 14 XN prepared in S1 with triphenylphosphine to obtain the organic cation salt C 33 H29 NP ＋ X － ; S3 The organic cationic raw material prepared in S2 is mixed with MnX2 and dissolved in an organic solvent to obtain a precursor solution; S4. The precursor solution in S3 is allowed to stand and the solvent is slowly evaporated to obtain manganese-based organic-inorganic hybrid metal halide.

[0009] Preferably, X in steps S1, S2, and S3 is one or more of F, Cl, Br, and I.

[0010] Preferably, in step S1, the molar ratio of carbazole to X(CH2)3X is 1:1.2; the prepared C 15 H 14 The structural formula for XN is:

[0011] Preferably, in step S2, C 15 H 14 The molar ratio of XN to triphenylphosphine is 2:3; the structural formula of the prepared organic cationic salt is:

[0012] Preferably, in step S3, the molar ratio of the organic cationic raw material to MnX2 is 2:1; the organic solvent is one or more of C2H6O, CH4O, CH2Cl2, and H2O. Preferably, the settling time in step S4 is 3 days; Thirdly, the present invention provides a method for preparing a manganese-based organic-inorganic hybrid metal halide scintillator thin film, comprising the following steps: S1. Manganese-based organic-inorganic hybrid metal halide scintillators are ground into powder and mixed with organic polymers in a certain proportion to obtain a polymer solution. S2 Take a certain volume of the polymer solution prepared by S1 and place it on a clean and flat glass substrate sprayed with a release agent, and use a scraper to coat it to form a film of a certain thickness. S3 After the glass plate coated with the polymer solution in S2 is placed in an oven for curing, it is demolded to obtain a manganese-based organic-inorganic hybrid metal halide scintillator film.

[0013] Preferably, the organic material in step S1 is PDMS or PMMA; the mass ratio of scintillator powder to organic polymer is 1:5. Preferably, the volume of the polymer solution taken in step S2 is 0.5~5 ml; the thickness of the film coated is 100~1000 μm; Preferably, the curing temperature in step S3 is 60~150℃; the curing time is 2~12 h.

[0014] Fourthly, the present invention provides a manganese-based organic-inorganic hybrid metal halide scintillator thin film, which is prepared by the above-described preparation method.

[0015] Fifthly, the present invention provides the application of the above-mentioned manganese-based organic-inorganic hybrid metal halide scintillator thin film in the fields of X-ray imaging, radiation detection, industrial inspection or security inspection.

[0016] The present invention has the following beneficial effects: (1) The present invention designs and synthesizes a manganese-based organic-inorganic hybrid metal halide scintillator, which is prepared by the "slow evaporation method of solution". This material is environmentally friendly, has a simple preparation method, low cost, and can be produced and applied on a large scale.

[0017] (2) The manganese-based organic-inorganic hybrid metal halide scintillator provided by the present invention has excellent light-emitting performance and can obtain 518 nm green light under light excitation of 250~360 nm and 420~510 nm, with a photoluminescence quantum efficiency of up to 99.2%.

[0018] (3) The manganese-based organic-inorganic hybrid metal halide scintillator provided by the present invention exhibits good scintillation performance under X-ray irradiation, including a light yield of up to 56363 photons / MeV and a light yield as low as 55.73 nGy. air It has a detection limit of / s and excellent radiation stability.

[0019] (4) The manganese-based organic-inorganic hybrid metal halide scintillator film prepared by the present invention has good mechanical properties, can be repeatedly bent, stretched and compressed, and can be used for high-resolution X-ray imaging with an imaging resolution of 15.5 lp / mm. Attached Figure Description

[0020] Figure 1 The flowcharts are for the preparation processes of Examples 1 and 4.

[0021] Figure 2 The (C) prepared in Example 5 33 H 29 Powder XRD of NP)2MnBr4·EtOH scintillator and its single crystal diffraction results are fitted with powder XRD.

[0022] Figure 3 The (C) prepared in Example 5 33 H 29 Excitation and emission spectra of NP)2MnBr4·EtOH scintillators.

[0023] Figure 4 The (C) prepared in Example 5 33 H 29 Photoluminescence quantum efficiency test of NP)2MnBr4·EtOH scintillator.

[0024] Figure 5 The (C) prepared in Example 5 33 H 29 The light yield (LY) of the NP)2MnBr4·EtOH scintillator was determined using the commercial scintillator LuAG:Ce (LY = 25,000 photons MeV). -1 (This is used as a standard reference.)

[0025] Figure 6 The (C) prepared in Example 5 33 H 29 The signal-to-noise ratio of NP)2MnBr4·EtOH scintillator under different X-ray doses was determined, and its detection limit was obtained by linear fitting.

[0026] Figure 7 The (C) prepared in Example 5 33 H 29 Radiation stability of NP)2MnBr4·EtOH scintillator under periodic X-ray irradiation.

[0027] Figure 8 The manganese-based organic-inorganic hybrid metal halide (C) prepared in Example 7 33 H 29 Images of NP)2MnBr4·EtOH thin films under sunlight and ultraviolet light.

[0028] Figure 9 The manganese-based organic-inorganic hybrid metal halide (C) prepared in Example 7 33 H 29 Spatial resolution of NP)2MnBr4·EtOH thin films calculated by modulation transfer function.

[0029] Figure 10 The manganese-based organic-inorganic hybrid metal halide (C) prepared in Example 7 33 H 29 Imaging demonstration of NP)2MnBr4·EtOH thin film. Detailed Implementation

[0030] The technical solutions of the present invention will be further described below with reference to specific embodiments and accompanying drawings. However, the following embodiments are only for enhancing the illustration of the technical solutions of the present invention and should not be construed as any limitation on the scope of the claimed invention. Furthermore, the described embodiments are merely some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, any modifications, equivalent substitutions, improvements, etc., made by those skilled in the art without creative effort to obtain all other embodiments should be included within the protection scope of the present invention.

[0031] Example 1 C 15 H 14 Preparation of BrN: 5 g of carbazole was dissolved in approximately 120 ml of dry acetone in a 250 ml round-bottom flask, and then 2.392 g of 60% sodium hydride was added. As hydrogen gas escaped, the colorless solution became turbid. After 45 minutes, 1.2 molar equivalents of 1,3-dibromopropane (35.88 mmol) were added, and the mixture was refluxed at 70 °C for 12 hours. The turbid solution turned into a clear honey-colored solution. The reaction was then stopped, and a new strong spot was observed by thin-layer chromatography (TLC). The solvent was then removed under vacuum, and the resulting crude solid was washed three times with dichloromethane (DCM), distilled water, and a brine solution until the alkali in the organic layer was completely removed. The organic layer was dried with anhydrous sodium sulfate. The mixture was purified by column chromatography using silica gel (100-200 mesh) as the adsorbent and petroleum ether / dichloromethane (9:1, v / v) as the eluent to obtain a colorless solid C. 15 H 14 BrN.

[0032] Figure 1 Example 1 illustrates the preparation of C 15 H 14 The process of BrN.

[0033] Example 2 C 15 H 14 Preparation of ClN: 5 g of carbazole was dissolved in approximately 120 ml of dry acetone in a 250 ml round-bottom flask, and then 2.392 g of 60% sodium hydride was added. As hydrogen gas escaped, the colorless solution became turbid. After 45 minutes, 1.2 molar equivalents of 1,3-dichloropropane (35.88 mmol) were added, and the mixture was refluxed at 70 °C for 12 hours. The turbid solution turned clear and honey-colored. The reaction was then stopped, and a new strong spot was observed by thin-layer chromatography (TLC). The solvent was then removed under vacuum, and the resulting crude solid was washed three times with dichloromethane (DCM), distilled water, and a brine solution until the alkali in the organic layer was completely removed. The organic layer was dried with anhydrous sodium sulfate. The mixture was purified by column chromatography using silica gel (100-200 mesh) as the adsorbent and petroleum ether / dichloromethane (9:1, v / v) as the eluent to obtain a colorless solid C. 15 H 14 ClN.

[0034] Example 3 Organochlorine salts C 33 H 29 NP ＋ Cl － Preparation Specifically, the C prepared in Example 2 15 H 14 ClN (6.97 mmol) and triphenylphosphine (10.45 mmol) were mixed in approximately 150 mL of toluene and stirred at 130 °C for 24 hours under a nitrogen atmosphere. After cooling to room temperature, white crystals appeared in the solution. Product C was obtained by filtering the turbid solution. 33 H 29 NP ＋ Cl － The solid was purified by recrystallization in isopropanol.

[0035] Example 4 Organic bromine salt C 33 H 29 NP ＋ Br － Preparation Specifically, the C prepared in Example 1 15 H 14 BrN (6.97 mmol) and triphenylphosphine (10.45 mmol) were mixed in approximately 150 mL of toluene and stirred at 130 °C for 24 hours under a nitrogen atmosphere. After cooling to room temperature, white crystals appeared in the solution. Product C was obtained by filtering the turbid solution. 33 H 29 NP ＋ Br －The solid was purified by recrystallization in isopropanol.

[0036] Figure 1 Example 4 illustrates the preparation of C 33 H 29 NP ＋ Br － The process.

[0037] Example 5 Manganese-based organic-inorganic hybrid metal halides (C 33 H 29 Preparation of NP)2MnBr4·EtOH Growth was achieved using the slow evaporation method (C 33 H 29 NP)2MnBr4·EtOH single crystal. 2 mmol of C 33 H 29 NP ＋ Br － 1 mmol of MnBr2 was dissolved in a mixed solvent of ethanol and dichloromethane (volume ratio 2:8), and stirred at 60 °C for 1 hour to form a clear solution, yielding the precursor solution. This precursor solution was then filtered into a 10 ml glass bottle, sealed with a microporous nylon membrane, and evaporated at room temperature in a fume hood. After 3 days, a light green, transparent (C)-containing substance grew in the glass bottle. 33 H 29 NP)2MnBr4·EtOH crystals.

[0038] Figure 2 The (C) prepared in Example 5 is shown. 33 H 29 A comparison of the powder XRD pattern of the NP)2MnBr4·EtOH scintillator and the powder XRD pattern fitted by its single crystal diffraction results shows that the peak positions of the two are consistent, indicating that the prepared scintillator is a pure phase.

[0039] Figure 3 The (C) prepared in Example 5 is shown. 33 H 29 The excitation and emission spectra of the NP)2MnBr4·EtOH scintillator show that it can produce 518 nm green light under light excitation at 250~360 nm and 420~510 nm.

[0040] Figure 4 The (C) prepared in Example 5 is shown. 33 H 29 The photoluminescence quantum efficiency test results of the NP)2MnBr4·EtOH scintillator are shown in the figure. As can be seen from the figure, the photoluminescence quantum efficiency of this scintillator is as high as 99.2%.

[0041] Figure 5 The (C) prepared in Example 5 is shown. 33 H 29 The light yield (LY) of the NP)2MnBr4·EtOH scintillator was measured. As can be seen from the figure, the scintillator has a light yield as high as 56363 photons / MeV.

[0042] Figure 6 The (C) prepared in Example 5 is shown. 33 H 29 The signal-to-noise ratio and detection limit of the NP)2MnBr4·EtOH scintillator at different X-ray doses are shown in the figure. As can be seen from the figure, this scintillator has a signal-to-noise ratio as low as 55.73 nGy. air The detection limit is 1 / s.

[0043] Figure 7 The (C) prepared in Example 5 is shown. 33 H 29 The radiation stability of the NP)2MnBr4·EtOH scintillator under periodic X-ray irradiation is shown in the figure. As can be seen from the figure, the radiation intensity of the scintillator did not decrease after multiple cycles of irradiation, indicating that it has excellent radiation stability.

[0044] Example 6 Manganese-based organic-inorganic hybrid metal halides (C 33 H 29 Preparation of NP)2MnCl4·EtOH Growth was achieved using the slow evaporation method (C 33 H 29 NP)2MnCl4·EtOH single crystals. 2 mmol of C 33 H 29 NP ＋ Cl － 1 mmol of MnCl2 was dissolved in a mixed solvent of ethanol and dichloromethane (volume ratio 2:8), and stirred at 60 °C for 1 hour to form a clear solution, yielding the precursor solution. This precursor solution was then filtered into a 10 ml glass bottle, sealed with a microporous nylon membrane, and evaporated at room temperature in a fume hood. After 3 days, a light green, transparent (C)-containing substance grew in the glass bottle. 33 H 29 NP)2MnCl4·EtOH crystals.

[0045] Example 7 Manganese-based organic-inorganic hybrid metal halides (C 33 H 29 Preparation of NP)2MnBr4·EtOH thin films (C) 33 H29 NP)2MnBr4·EtOH single crystals were ground into powder in a mortar and passed through a 300-mesh sieve. The sieved powder and PDMS were mixed separately at a mass ratio of 1:5 and stirred evenly to obtain a mixed gel. 1 ml of the mixed gel was placed on a clean and flat glass substrate sprayed with a release agent and coated with a doctor blade to form a 300 μm film. The glass plate coated with the mixed gel was placed in an oven at 100℃ for curing for 4 hours. After the mixed gel cooled to room temperature, it was demolded to obtain a manganese-based organic-inorganic hybrid metal halide scintillator film.

[0046] Figure 8 The manganese-based organic-inorganic hybrid metal halide (C) prepared in Example 7 is shown. 33 H 29 Images of the NP)2MnBr4·EtOH film under sunlight and ultraviolet light irradiation show that the film has good mechanical properties and can be repeatedly bent, stretched and compressed.

[0047] Figure 9 The manganese-based organic-inorganic hybrid metal halide (C) prepared in Example 7 is shown. 33 H 29 The spatial resolution of the NP)2MnBr4·EtOH thin film is shown in the figure. As can be seen from the figure, the imaging resolution of the thin film is 15.5 lp / mm, which can be used for high-resolution X-ray imaging.

[0048] Figure 10 The manganese-based organic-inorganic hybrid metal halide (C) prepared in Example 7 is shown. 33 H 29 Imaging demonstration of NP)2MnBr4·EtOH thin film.

[0049] Example 8 Manganese-based organic-inorganic hybrid metal halides (C 33 H 29 Preparation of NP)2MnCl4·EtOH thin films (C) 33 H 29 NP)2MnCl4·EtOH single crystals were ground into powder in a mortar and passed through a 300-mesh sieve. The sieved powder was mixed with PDMS at a mass ratio of 1:5 and stirred until homogeneous to obtain a mixed gel. 1 ml of the mixed gel was placed on a clean, flat glass substrate sprayed with a release agent and coated with a doctor blade to form a 300 μm film. Three glass plates coated with the mixed gel were placed in an oven at 100°C for 4 hours to cure. After the mixed gel cooled to room temperature, it was demolded to obtain a manganese-based organic-inorganic hybrid metal halide scintillator film.

[0050] In summary, the present invention has the following beneficial effects: (1) The present invention designs and synthesizes a manganese-based organic-inorganic hybrid metal halide scintillator, which is prepared by the "slow evaporation method of solution". This material is environmentally friendly, has a simple preparation method, low cost, and can be produced and applied on a large scale.

[0051] (2) The manganese-based organic-inorganic hybrid metal halide scintillator provided by the present invention has excellent light-emitting performance and can obtain 518 nm green light under light excitation of 250~360 nm and 420~510 nm, with a photoluminescence quantum efficiency of up to 99.2%.

[0052] (3) The manganese-based organic-inorganic hybrid metal halide scintillator provided by the present invention exhibits good scintillation performance under X-ray irradiation, including a light yield of up to 56363 photons / MeV and a light yield as low as 55.73 nGy. air It has a detection limit of / s and excellent radiation stability.

[0053] (4) The manganese-based organic-inorganic hybrid metal halide scintillator film prepared by the present invention has good mechanical properties, can be repeatedly bent, stretched and compressed, and can be used for high-resolution X-ray imaging with an imaging resolution of 15.5 lp / mm.

Claims

1. A manganese-based organic-inorganic hybrid metal halide, characterized in that, The chemical composition of the manganese-based organic-inorganic hybrid metal halide is (C 33 H 29 NP) x MnX y ·zL, where X is one or more of F, Cl, Br, and I, 0 < x ≤ 2, 0 < y ≤ 4, L is one or more of C2H6O, CH4O, CH2Cl2, and H2O, and z ≥ 0.

2. A method for preparing a manganese-based organic-inorganic hybrid metal halide as described in claim 1, characterized in that, Manganese-based organic-inorganic hybrid metal halides are prepared by slow evaporation of organic cationic raw materials and MnX2 in solution. The specific steps are as follows: S1 Under alkaline conditions, carbazole undergoes a mononuclear nucleophilic substitution reaction with X(CH2)3X to produce C. 15 H 14 XN; S2 will prepare C from S1 15 H 14 The organic cationic salt C was prepared by mixing XN with triphenylphosphine. 33 H 29 NP ＋ X － ; S3 The organic cationic raw material prepared in S2 is mixed with MnX2 and dissolved in an organic solvent to obtain a precursor solution; S4 The precursor solution in S3 was allowed to stand and the solvent was slowly evaporated to obtain manganese-based organic-inorganic hybrid metal halide. Where X is one or more of F, Cl, Br, and I.

3. The preparation method according to claim 2, characterized in that, In step S1, the molar ratio of carbazole to X(CH2)3X is 1:1.2; the C 15 H 14 XN, its structural formula is: Where X is F, Cl, Br, or I.

4. The preparation method according to claim 2, characterized in that, In step S2, the C 15 H 14 The molar ratio of XN to triphenylphosphine is 2:3; the C 33 H 29 NP ＋ X － Its structural formula is: Where X is F, Cl, Br, or I.

5. The preparation method according to claim 2, characterized in that, In step S3, the molar ratio of the organic cationic raw material to MnX2 is 2:1; the organic solvent is one or more of C2H6O, CH4O, CH2Cl2, and H2O.

6. A method for preparing a manganese-based organic-inorganic hybrid metal halide scintillator thin film, characterized in that, Includes the following steps: S1 grinds a manganese-based organic-inorganic hybrid metal halide as described in claim 1 into powder and mixes it with an organic polymer in a certain proportion to obtain a polymer solution. S2 Take a certain volume of the polymer solution prepared by S1 and place it on a clean and flat glass substrate sprayed with a release agent, and use a scraper to coat it to form a film of a certain thickness. S3 After the glass plate coated with the polymer solution in S2 is placed in an oven for curing, it is demolded to obtain a manganese-based organic-inorganic hybrid metal halide scintillator film.

7. The preparation method according to claim 6, characterized in that, In step S1, the mass ratio of the scintillator powder to the organic polymer is 1:5; the organic polymer is PDMS or PMMA.

8. The preparation method according to claim 6, characterized in that, In step S2, the thickness of the film coated by scraping is 100~1000 μm; in step S3, the curing temperature is 60~150℃; and the curing time is 2~12 h.

9. A manganese-based organic-inorganic hybrid metal halide scintillator thin film, characterized in that, The thin film is prepared by the preparation method according to any one of claims 7 to 8.

10. The application of the manganese-based organic-inorganic hybrid metal halide scintillator thin film as described in claim 9 in the fields of X-ray imaging, radiation detection, industrial inspection, or security inspection.

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