Neodymium-doped phenethylamine lead bromide monocrystal capable of greatly shortening light emission decay time and application thereof

Abstract

The application relates to a neodymium-doped phenethylamine lead bromide monocrystal capable of greatly shortening light emission decay time and an application thereof, and solves the technical problem of long light emission decay time of an existing phenethylamine lead bromide monocrystal. The neodymium-doped phenethylamine lead bromide monocrystal capable of greatly shortening light emission decay time is prepared by the following steps: 1) weighing; phenethylamine hydrobromide, lead bromide and neodymium bromide are weighed and placed in a glass bottle; the mass ratio of the phenethylamine hydrobromide, the lead bromide and the neodymium bromide is (2.0-2.4):0.8:0.2; 2) obtaining a precursor solution; N,N-dimethylformamide is added to the glass bottle, heated and stirred until completely dissolved to obtain the precursor solution; 3) obtaining a crystal; the precursor solution is filtered and then placed in a glass beaker to crystallize, so that the neodymium-doped phenethylamine lead bromide monocrystal is obtained, the light emission decay time of which can be greatly shortened by about 3 times, but the quantum yield is not significantly reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to a neodymium-doped phenethylamine lead bromide single crystal with a greatly shortened luminescence decay time and an application thereof. BACKGROUND

[0002] Phenethylamine lead bromide (PEA2PbBr4) is a two-dimensional perovskite scintillator with a natural quantum well structure and a large exciton binding energy. Therefore, it can emit bright blue light under room temperature ionizing radiation excitation. Its luminescence decay time is shorter than that of commercial scintillators such as NaI, BGO and LYSO. Its preparation process is simple, and its cost is relatively low. Therefore, it has great application potential. However, its decay time is still relatively long, which limits its application in the field of ultrafast ionizing radiation detection.

[0003] At present, the methods for adjusting the luminescence decay time have certain limitations. For example, by replacing bromine with iodine, the luminescence decay time can be increased by an order of magnitude, but the light yield also decreases by an order of magnitude, and the coupling efficiency with a conventional photomultiplier tube decreases. By replacing some bromine atoms with chlorine atoms or by doping interstitial atoms, the light yield and the luminescence decay time can be increased, but the effect of shortening the luminescence decay time is very limited. By replacing atoms at certain positions on the benzene ring, the luminescence decay time can be shortened to a certain extent, but the effect is poor and the luminescence efficiency of the crystal is significantly reduced. SUMMARY

[0004] The present application aims to solve the technical problem of long luminescence decay time of the existing phenethylamine lead bromide single crystal, and provides a neodymium-doped phenethylamine lead bromide single crystal with a greatly shortened luminescence decay time and an application thereof.

[0005] In order to achieve the above-mentioned purpose, the present application adopts the following technical solutions:

[0006] A neodymium-doped phenethylamine lead bromide single crystal with a greatly shortened luminescence decay time, characterized in that it is prepared by the following steps:

[0007] 1) weighing;

[0008] Phenethylamine hydrobromide, lead bromide and neodymium bromide are weighed and placed in a glass bottle. The mass ratio of the phenethylamine hydrobromide, lead bromide and neodymium bromide is (2.0-2.4):0.8:0.2;

[0009] 2) obtaining a precursor solution;

[0010] N,N-dimethylformamide is added to the glass bottle, heated and stirred until completely dissolved to obtain a precursor solution;

[0011] 3) obtaining a crystal;

[0012] After filtering the precursor solution, it was placed in a glass beaker for crystallization to obtain neodymium-doped phenylethylamine lead bromine single crystals.

[0013] Further, in step 1), the molar ratio of phenylethylamine hydrobromide, lead bromide, and neodymium bromide in the precursor solution is 2.0:0.8:0.2.

[0014] Furthermore, step 3) specifically involves:

[0015] After filtering the precursor solution, it was placed in a glass beaker, and neodymium-doped phenylethylamine lead bromine single crystals were obtained by solvent evaporation, cooling crystallization, or anti-solvent crystallization.

[0016] Further, in step 3), the amount of neodymium is 0.4% ± 0.1% of the amount of lead.

[0017] Furthermore, it also includes step 4):

[0018] The neodymium-doped phenylethylamine lead bromine single crystal was removed, the surface solution was dried, and it was cleaned with an anti-solvent and then vacuum dried at room temperature to obtain a neodymium-doped phenylethylamine lead bromine single crystal scintillator.

[0019] Further, in step 4), the antisolvent is cyclohexane or chlorobenzene.

[0020] This invention also proposes the application of the above-mentioned single crystal in ionizing radiation.

[0021] The beneficial effects of this invention are:

[0022] This invention provides a neodymium-doped phenylethylamine lead bromine single crystal that can significantly shorten the light emission decay time. By doping the crystal with neodymium, the light emission decay time can be significantly shortened by about 3 times without significantly reducing its quantum yield, providing a new approach for the design of ultrafast scintillators. Attached Figure Description

[0023] Figure 1 This is a graph showing the short-wavelength emission decay time of the neodymium-doped phenylethylamine lead bromide single crystal (Doped, blue scattered dots) and the undoped neodymium single crystal (Pristine, red scattered dots) in Example 1 of the present invention, respectively excited by laser.

[0024] Figure 2 This is a graph showing the long-wavelength emission decay time of the neodymium-doped phenylethylamine lead bromide single crystal (blue scattered dots) and the undoped neodymium single crystal (red scattered dots) in Example 1 of this invention, respectively excited by laser. Detailed Implementation

[0025] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0026] Example 1

[0027] A neodymium-doped phenylethylamine lead-bromine single crystal with a significantly shortened luminescence decay time is prepared as follows: 20 mmol of phenylethylamine hydrobromide (PEABr), 8 mmol of lead bromide (PbBr2), and 2 mmol of neodymium bromide (NdBr3) are weighed into a glass reagent bottle. 6.9 mL of N,N-dimethylformamide (DMF) is added, and the solution is heated and stirred until completely dissolved, preparing a precursor solution with a lead content of 1.45 mol / L. This solution is filtered using a 0.45 μm pore size filter and transferred to a 100 mL glass beaker. The neodymium-doped phenylethylamine lead-bromine single crystal is then prepared by solvent evaporation. The neodymium-doped phenylethylamine lead-bromine single crystal is removed with tweezers, the surface solution is blotted dry with filter paper, washed with cyclohexane, and then vacuum-dried for 24 h before storage.

[0028] The neodymium-doped phenylethylamine lead bromine single crystal prepared using Example 1 can be applied in ionizing radiation.

[0029] Comparative Example

[0030] Weigh 20 mmol PEABr (4.0500 g) and 10 mmol PbBr2 (3.6700 g) into a glass reagent bottle, add 7.4 mL DMF, heat and stir until completely dissolved to prepare a solution with a lead content of 1.35 mol / L. Filter the solution and transfer it to a 100 mL glass beaker. Prepare phenylethylamine lead bromine single crystals by solvent evaporation. Remove the crystals with tweezers, blot the surface solution with filter paper, wash with cyclohexane, and vacuum dry for 24 h before storage.

[0031] The photoluminescence spectra of both undoped and neodymium-doped phenylethylamine lead bromide single crystals contained two emission peaks, located at 410 nm and 438 nm, respectively. The decay times of the two emission peaks were different. In order to comprehensively analyze the effect of the neodymium doping concentration on the emission decay time of the crystal, the emission decay times of the two emission peaks of the two crystals were measured and compared.

[0032] like Figure 1 The figure shows the emission decay time of the short-wavelength emission peak of undoped neodymium phenylethylamine lead bromide single crystal (Pristine) excited by laser and neodymium-doped neodymium phenylethylamine lead bromide single crystal (Doped) prepared according to Example 1 of the present invention; the horizontal axis represents time and the vertical axis represents emission intensity.Figure 1 The red scatter plots represent the luminescence decay time data of undoped phenylethylamine lead-bromine single crystals, while the blue scatter plots represent the luminescence decay time data of neodymium-doped phenylethylamine lead-bromine single crystals. The red and blue solid lines are the double-exponential fitting curves for the two components, respectively. The Doped fitting yielded a luminescence lifetime τ1 of 0.98 ns for the fast-luminescence component and a luminescence lifetime τ2 of 3.75 ns for the slow-luminescence component. The fast-luminescence component accounts for 32.6% of the luminescence lifetime, and the slow-luminescence component accounts for 67.4%. Figure 1 It can be seen that the lifetimes of both the fast and slow components of the short-wavelength emission peak are shortened to about one-third of their original values, and the proportion of the fast component's emission lifetime is increased.

[0033] like Figure 2 The diagram shows the emission decay time of the long-wavelength emission peaks of undoped neodymium-doped phenylethylamine lead-bromine single crystals and neodymium-doped phenylethylamine lead-bromine single crystals excited by lasers. The horizontal axis represents time, and the vertical axis represents emission intensity. Figure 2 The red and blue scatter plots represent the luminescence decay time data for undoped and doped neodymium-doped phenylethylamine lead-bromine single crystals, respectively. The red and blue solid lines are the double-exponential fitting curves for the two components. The Doped curve shows a luminescence lifetime τ1 of 1.80 ns for the fast-luminescence component and a luminescence lifetime τ2 of 6.74 ns for the slow-luminescence component. Figure 2 As can be seen, the lifetimes of both the fast and slow components of the long-wavelength emission peak are shortened to about one-third of their original length.

[0034] Example 2

[0035] 22 mmol of phenylethylamine hydrobromide (PEABr), 8 mmol of lead bromide (PbBr2), and 2 mmol of neodymium bromide (NdBr3) were weighed into a glass reagent bottle. 7.145 mL of N,N-dimethylformamide (DMF) was added, and the solution was heated and stirred until completely dissolved, preparing a precursor solution with a lead content of 1.4 mol / L. This solution was filtered through a 0.45 μm pore size filter and transferred to a 100 mL glass beaker. Neodymium-doped phenylethylamine lead bromide single crystals were prepared by anti-solvent evaporation. The NdBr3 single crystals were removed with tweezers, the surface solution was blotted dry with filter paper, washed with chlorobenzene, and then vacuum-dried for 24 h before storage.

[0036] Example 3

[0037] Weigh 24 mmol of phenethylamine hydrobromide (PEABr), 8 mmol of lead bromide (PbBr2), and 2 mmol of neodymium bromide (NdBr3) into a glass reagent bottle, add 6.45 mL of N,N-dimethylformamide (DMF), heat to 70 °C and stir until completely dissolved to prepare a precursor solution with a lead content of 1.55 mol / L. Filter the solution hot into a 100 mL glass beaker using a 0.45 μm pore size filter. Prepare neodymium-doped phenethylamine lead bromide single crystals by cooling crystallization. Remove the neodymium-doped phenethylamine lead bromide single crystals with tweezers, blot dry the surface solution with filter paper, wash with cyclohexane, vacuum dry for 24 h, and then store.

[0038] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions within the technical scope disclosed in the present invention should be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A neodymium-doped phenylethylamine lead bromide single crystal that can significantly shorten the luminescence decay time, characterized in that, Prepared using the following steps: 1) Weighing; Phenethylamine hydrobromide, lead bromide, and neodymium bromide are weighed and placed in a glass bottle; the molar ratio of phenethylamine hydrobromide, lead bromide, and neodymium bromide is (2.0-2.4):0.8:0.

2. 2) Obtain the precursor solution; Add N,N-dimethylformamide to a glass bottle, heat and stir until completely dissolved to obtain a precursor solution; 3) Obtain the crystal; The precursor solution was filtered and placed in a glass beaker for crystallization to obtain neodymium-doped phenylethylamine lead bromine single crystals. The amount of neodymium in the single crystals was 0.4% ± 0.1% of the amount of lead.

2. The neodymium-doped phenylethylamine lead bromide single crystal according to claim 1, which can significantly shorten the luminescence decay time, is characterized in that: In step 1), the molar ratio of phenylethylamine hydrobromide, lead bromide, and neodymium bromide in the precursor solution is 2.0:0.8:0.

2.

3. The neodymium-doped phenylethylamine lead bromide single crystal according to claim 1, which can significantly shorten the luminescence decay time, is characterized in that, Step 3) specifically refers to: After filtering the precursor solution, it was placed in a glass beaker, and neodymium-doped phenylethylamine lead bromine single crystals were obtained by solvent evaporation, cooling crystallization, or anti-solvent crystallization.

4. A neodymium-doped phenylethylamine lead bromide single crystal according to claim 2 or 3, characterized in that, It also includes step 4): The neodymium-doped phenylethylamine lead bromine single crystal was removed, the surface solution was dried, and it was cleaned with an anti-solvent and then vacuum dried at room temperature to obtain a neodymium-doped phenylethylamine lead bromine single crystal scintillator.

5. The neodymium-doped phenylethylamine lead bromide single crystal according to claim 4, which can significantly shorten the luminescence decay time, is characterized in that: In step 4), the antisolvent is cyclohexane or chlorobenzene.

6. The application of neodymium-doped phenylethylamine lead bromide single crystals, which can significantly shorten the luminescence decay time according to any one of claims 1-5, in ionizing radiation.

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