Neodymium-doped butylamine lead bromide single crystal with differentially adjustable luminescence decay time under gamma / alpha ray excitation

Abstract

The invention particularly relates to a neodymium-doped butylamine lead bromide single crystal with differentially adjustable luminescence decay time under gamma / alpha ray excitation, and solves the technical problem that the existing two-dimensional perovskite performance regulation and control method is difficult to realize differentially regulate and control the response of different radiation rays. The neodymium-doped butylamine lead bromide single crystal with differentially adjustable luminescence decay time under gamma / alpha ray excitation is prepared by the following method: 1) weighing; the preparation method comprises the following steps: weighing butylamine hydrobromide, lead bromide and neodymium bromide, and putting into a glass bottle; the concentration ratio of butylamine hydrobromide to lead bromide to neodymium bromide is 2: 1: (0.2-0.7); 2) obtaining a precursor solution; 3) obtaining a crystal; the precursor solution is filtered and then put into a glass beaker to be crystallized, the neodymium-doped butylamine lead bromide single crystal is obtained, and the decay time of response of the two-dimensional perovskite to gamma / alpha rays can be adjusted differentially.

Description

Technical Field

[0001] The present invention specifically relates to a neodymium-doped butylamine lead bromide single crystal whose luminescence decay time can be differentially adjusted under gamma / alpha ray excitation. Background Art

[0002] Scintillator is a key component of indirect radiation detection system. Its response time is one of the key technical indicators of scintillator, which directly affects the time resolution of the detection system. At the same time, the difference in the response characteristics of scintillator to different radiation rays is a necessary condition for ray waveform identification, and its response time is one of the important performance indicators of scintillator.

[0003] Two-dimensional perovskite materials have a natural quantum well structure and a large exciton binding energy, so they can emit light when excited by ionizing radiation at room temperature, making them a suitable scintillator. Their luminescence decay time is shorter than that of commercial scintillators such as NaI, BGO, and LYSO, and their preparation process is simple and the cost is low, so they have great application potential in the field of ultrafast radiation detection.

[0004] The response time of existing two-dimensional perovskites to different rays is slightly different, and the ability to discriminate ray waveforms is limited; methods for regulating the luminescence decay time of two-dimensional perovskites include partial or full replacement of halogen atoms, aliovalent ion doping, organic amine ion modification, etc., but there is no solution for differentiated regulation of different radiation rays. Summary of the invention

[0005] The purpose of the present invention is to solve the technical problem that the existing two-dimensional perovskite performance regulation method is difficult to achieve differentiated regulation of the response to different radiation rays, and to provide a neodymium-doped butylamine lead bromide single crystal with differentially adjustable luminescence decay time under γ / α ray excitation.

[0006] In order to achieve the above object, the present invention adopts the following technical solution:

[0007] A neodymium-doped butylamine lead bromide single crystal whose luminescence decay time can be differentially adjusted under γ / α ray excitation is special in that it is prepared by the following method:

[0008] 1) Weighing;

[0009] Weigh butylamine hydrobromide, lead bromide and neodymium bromide and place them in a glass bottle; the concentration ratio of butylamine hydrobromide, lead bromide and neodymium bromide is 2:1:(0.2-0.7);

[0010] 2) obtaining a precursor solution;

[0011] Add N,N-dimethylformamide to a glass bottle, heat and stir until completely dissolved to obtain a precursor solution;

[0012] 3) obtaining crystals;

[0013] The precursor solution is filtered and placed in a glass beaker for crystallization to obtain a neodymium-doped butylamine lead bromide single crystal;

[0014] The amount of neodymium in the neodymium-doped butylamine lead bromide single crystal is 0.4% to 0.8% of lead.

[0015] Furthermore, in step 2), the purity of butylamine hydrobromide, neodymium bromide and lead bromide in the precursor solution is greater than 98%.

[0016] Furthermore, in step 2), the N,N-dimethylformamide is anhydrous grade N,N-dimethylformamide with a purity greater than 99.5%.

[0017] Further, step 3) is specifically as follows:

[0018] The precursor solution is filtered and placed in a glass beaker, and crystallized by a solvent evaporation method, a cooling crystallization method, or an anti-solvent crystallization method to obtain a neodymium-doped butylamine lead bromide single crystal.

[0019] Furthermore, in step 3), the filtration uses a nylon filter head with a pore size of 0.45 microns.

[0020] Furthermore, the method further comprises step 4):

[0021] The neodymium-doped butylamine lead bromide single crystal is taken out, the surface solution is dried, and the crystal is cleaned with an anti-solvent and then vacuum-dried at room temperature to obtain a neodymium-doped butylamine lead bromide single crystal scintillator.

[0022] Furthermore, in step 4), the anti-solvent is cyclohexane or chlorobenzene.

[0023] Beneficial effects of the present invention:

[0024] 1. The present invention discloses a neodymium-doped butylamine lead bromide single crystal whose luminescence decay time can be differentially adjusted under γ / α ray excitation. A high concentration of neodymium is doped into the raw materials (i.e., butylamine hydrobromide and lead bromide) to obtain the neodymium-doped butylamine lead bromide single crystal. The lattice of the neodymium-doped butylamine lead bromide single crystal regulates the energy band of the neodymium-doped butylamine lead bromide single crystal, constrains the movement of carriers generated by radiation, and accelerates the radiation recombination rate of the carriers. At the same time, by utilizing the constraint of neodymium on the movement of carriers, the proportion of Auger recombination (one of the important non-radiation recombination modes under high ionization density) caused by γ / α rays in the carrier recombination is differentially adjusted, thereby differentially adjusting the non-radiation recombination rate of carriers, and finally differentially adjusting the decay time of the two-dimensional perovskite in response to γ / α rays.

[0025] 2. The present invention discloses a neodymium-doped butylamine lead bromide single crystal whose luminescence decay time can be differentially adjusted under γ / α ray excitation, which can increase the difference in response time of the two-dimensional perovskite butylamine lead bromide single crystal to γ / α rays, and provide a reference for the development of perovskite scintillators with ray discrimination capabilities. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 The neodymium-doped butylamine lead bromide single crystal scintillator in Example 1 of the present invention is respectively subjected to 137 The gamma rays produced by Cs and 241 The luminescence decay time diagram of α-ray excitation produced by Am;

[0027] Figure 2 The neodymium-doped butylamine lead bromide single crystal scintillator in Example 2 of the present invention is respectively subjected to 137 The gamma rays produced by Cs and 241 The luminescence decay time diagram of α-ray excitation produced by Am;

[0028] Figure 3 The scintillators not doped with neodymium in the comparative example were subjected to 137 The gamma rays produced by Cs and 241 Decay time diagram of luminescence excited by α rays produced by Am. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] Example 1

[0031] The present invention provides a method for preparing a neodymium-doped butylamine lead bromide single crystal whose luminescence decay time can be differentially adjusted under γ / α ray excitation, comprising the following steps:

[0032] Weigh 20mmol butylamine hydrobromide (BABr), 10mmol lead bromide (PbBr2), and 2mmol neodymium bromide (NdBr3) in a glass reagent bottle, add 7.4mL N,N-dimethylformamide (DMF), heat and stir on a heating table until completely dissolved, filter the solution with a nylon filter with a pore size of 0.45 microns and transfer it to a 100mL glass beaker, and prepare neodymium-doped butylamine lead bromide single crystals by solvent evaporation. Take out the neodymium-doped butylamine lead bromide single crystal with tweezers, dry the surface solution with filter paper, rinse with cyclohexane, and store it after vacuum drying for 24 hours. After testing, the amount of neodymium in the neodymium-doped single crystal is 0.48% of lead.

[0033] like Figure 1 As shown, using 137 The gamma rays produced by Cs and 241 The luminescence decay time diagram of the neodymium-doped phenylethylamine lead bromide scintillator excited by the α-rays generated by Am, the horizontal axis is time, the vertical axis is the luminescence intensity, from Figure 1 It can be seen that after doping with 0.48% neodymium (the amount of substance compared to the percentage of lead), the luminescence decay time of both γ and α rays is shortened to a certain extent, and the luminescence decay time of α rays is shortened more significantly.

[0034] Example 2

[0035] Weigh 10mmol butylamine hydrobromide (BABr), 5mmol lead bromide (PbBr2), and 3.5mmol neodymium bromide (NdBr3) in a glass reagent bottle, add 4.85mL N,N-dimethylformamide (DMF), heat and stir with a magnetic stirrer until completely dissolved, filter the solution with a nylon filter head with a pore size of 0.45 microns and transfer it to a 50mL glass beaker, and prepare neodymium-doped butylamine lead bromide single crystals by anti-solvent evaporation crystallization. Take out the neodymium-doped butylamine lead bromide single crystal with tweezers and then use filter paper to absorb the surface solution, then wash it with chlorobenzene and vacuum dry it for 24 hours before storing. After testing, the amount of neodymium in the neodymium-doped single crystal is 0.8% of lead.

[0036] like Figure 2 As shown, using 137 The gamma rays produced by Cs and 241 The luminescence decay time diagram of the neodymium-doped butylamine lead bromide single crystal scintillator is excited by the α rays generated by Am. The horizontal axis is time and the vertical axis is the luminescence intensity. Figure 2 It can be seen that after doping with 0.8% neodymium (the amount of substance compared to the percentage of lead), the luminescence decay time of α rays is shortened significantly, while the luminescence decay time of γ rays is not shortened significantly.

[0037] Comparative Example

[0038] Weigh 20mmol BABr (4.0500g) and 10mmol PbBr2 (3.6700g) in a glass reagent bottle, add 7.695mL DMF, heat and stir to completely dissolve, filter the solution with a nylon filter head with a pore size of 0.45 microns and transfer it to a 100mL glass beaker, and prepare butylamine lead bromide single crystals by solvent evaporation. Take out the neodymium-doped butylamine lead bromide single crystal with tweezers and then use filter paper to absorb the surface solution, then wash it with chlorobenzene and vacuum dry it for 24 hours before storing.

[0039] like Figure 3 As shown, using 137 The gamma rays produced by Cs and 241The luminescence decay time diagram of the undoped butylamine lead bromide single crystal scintillator excited by the α rays generated by Am, with the horizontal axis being time and the vertical axis being luminescence intensity. Figure 3 It can be seen that there is a certain difference in the luminescence decay time of γ / α rays, and the luminescence decay time of α rays is faster. Compared with the luminescence decay time of γ / α rays in Example 1 and the luminescence decay time of γ / α rays in Example 2, the difference in the luminescence decay time of γ / α rays of the undoped butylamine lead bromide single crystal is smaller.

[0040] Example 3

[0041] Weigh 20mmol butylamine hydrobromide (BABr), 10mmol lead bromide (PbBr2), and 4mmol neodymium bromide (NdBr3) in a glass reagent bottle, add 7.7mL N,N-dimethylformamide (DMF), heat and stir on a heating table until completely dissolved, filter the solution with a nylon filter head with a pore size of 0.45 microns and transfer it to a 100mL glass beaker, and prepare neodymium-doped butylamine lead bromide single crystals by solvent evaporation. Take out the neodymium-doped butylamine lead bromide single crystal with tweezers, absorb the surface solution with filter paper, rinse with cyclohexane, and vacuum dry for 24 hours before storage. After testing, the amount of neodymium in the neodymium-doped single crystal is 0.56% of lead.

[0042] Example 4

[0043] Weigh 20mmol butylamine hydrobromide (BABr), 10mmol lead bromide (PbBr2), and 5mmol neodymium bromide (NdBr3) in a glass reagent bottle, add 8mL N,N-dimethylformamide (DMF), heat and stir with a magnetic stirrer until completely dissolved, filter the solution with a nylon filter head with a pore size of 0.45 microns and transfer it to a 100mL glass beaker, and prepare neodymium-doped butylamine lead bromide single crystals by solvent evaporation. Take out the neodymium-doped butylamine lead bromide single crystal with tweezers, dry the surface solution with filter paper, rinse with cyclohexane, and vacuum dry for 24 hours before storage. Take out the neodymium-doped butylamine lead bromide single crystal with tweezers, dry the surface solution with filter paper, then wash with chlorobenzene, and vacuum dry for 24 hours before storage. After testing, the amount of neodymium in the neodymium-doped single crystal is 0.63% of lead.

[0044] Example 5

[0045] Weigh 20mmol butylamine hydrobromide (BABr), 10mmol lead bromide (PbBr2), and 6mmol neodymium bromide (NdBr3) in a glass reagent bottle, add 8.5mL N,N-dimethylformamide (DMF), heat and stir on a heating table until completely dissolved, filter the solution with a nylon filter head with a pore size of 0.45 microns and transfer it to a 100mL glass beaker, and prepare a neodymium-doped butylamine lead bromide single crystal by solvent evaporation. Take out the neodymium-doped butylamine lead bromide single crystal with tweezers, absorb the surface solution with filter paper, rinse with cyclohexane, and vacuum dry for 24 hours before storage. Take out the neodymium-doped butylamine lead bromide single crystal with tweezers, absorb the surface solution with filter paper, then wash with chlorobenzene, and vacuum dry for 24 hours before storage. After testing, the amount of neodymium in the neodymium-doped single crystal is 0.72% of lead.

[0046] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A neodymium-doped butylamine lead bromide single crystal whose luminescence decay time can be differentially adjusted under γ / α ray excitation, characterized in that: Prepared by the following method: 1) Weighing; Weigh butylamine hydrobromide, lead bromide and neodymium bromide and place them in a glass bottle; the concentration ratio of butylamine hydrobromide, lead bromide and neodymium bromide is 2:1:(0.2-0.7); 2) obtaining a precursor solution; Add N,N-dimethylformamide to a glass bottle, heat and stir until completely dissolved to obtain a precursor solution; 3) obtaining crystals; The precursor solution is filtered and placed in a glass beaker for crystallization to obtain a neodymium-doped butylamine lead bromide single crystal; The amount of neodymium in the neodymium-doped butylamine lead bromide single crystal is 0.4% to 0.8% of lead.

2. According to claim 1, the neodymium-doped butylamine lead bromide single crystal with differentially adjustable luminescence decay time under γ / α ray excitation, characterized in that: In step 2), the purity of butylamine hydrobromide, neodymium bromide and lead bromide in the precursor solution is greater than 98%.

3. According to claim 1, the neodymium-doped butylamine lead bromide single crystal with differentially adjustable luminescence decay time under γ / α ray excitation, characterized in that: In step 2), the N,N-dimethylformamide is anhydrous grade N,N-dimethylformamide with a purity greater than 99.5%.

4. A neodymium-doped butylamine lead bromide single crystal with differentially adjustable luminescence decay time under γ / α ray excitation according to claim 2 or 3, characterized in that: Step 3) is specifically: The precursor solution is filtered and placed in a glass beaker, and crystallized by a solvent evaporation method, a cooling crystallization method, or an anti-solvent crystallization method to obtain a neodymium-doped butylamine lead bromide single crystal.

5. According to claim 4, the neodymium-doped butylamine lead bromide single crystal with differentially adjustable luminescence decay time under γ / α ray excitation, characterized in that: In step 3), the filtration uses a nylon filter head with a pore size of 0.45 microns.

6. The neodymium-doped butylamine lead bromide single crystal with differentially adjustable luminescence decay time under γ / α ray excitation according to claim 5, characterized in that: Also includes step 4): The neodymium-doped butylamine lead bromide single crystal is taken out, the surface solution is dried, and the crystal is cleaned with an anti-solvent and then vacuum-dried at room temperature to obtain a neodymium-doped butylamine lead bromide single crystal scintillator.

7. The neodymium-doped butylamine lead bromide single crystal with differentially adjustable luminescence decay time under γ / α ray excitation according to claim 6, characterized in that: In step 4), the anti-solvent is cyclohexane or chlorobenzene.

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