Method for improving the detection performance of high-energy radiation of a powdered scintillator

Abstract

This invention discloses a method for improving the high-energy radiation detection performance of powdered scintillators, comprising the following steps: pulverizing and grinding scintillator material to obtain scintillator particles; completely or partially coating the surface of the scintillator particles with a metal layer having a surface plasmon effect; and then mixing with an organic polymer material to form a scintillator sheet. This invention rationally coats or partially covers the surface of the scintillator particles with a metal material. Based on the plasmon effect of the metal material, it can effectively increase the light yield of the scintillator and reduce its decay lifetime, thereby improving the scintillator's high-energy radiation detection performance. Moreover, the entire operation process is simple, convenient, and easy to implement, applicable to scintillator materials of various powder shapes, and has a wide range of applications, such as nuclear medicine imaging, security inspection, industrial detection, and high-energy physics.

Description

Technical Field

[0001] This invention relates to the field of powdered scintillator technology, and in particular to a method for improving the detection performance of powdered scintillators against high-energy rays. Background Technology

[0002] Scintillators are a class of materials with energy conversion capabilities, rapidly converting high-energy photons such as X-rays and gamma rays, or high-energy particles such as alpha particles and neutrons, into ultraviolet-visible pulsed fluorescence. They have important applications in medicine, industry, and scientific research. For example, the core component of positron emission tomography (PET) scanners used in molecular medical imaging is a scintillator crystal with a closed-loop array distribution. In high-energy physics, scintillator crystals are crucial materials for manufacturing electromagnetic energy collectors in various colliders. In space physics, detectors with scintillators as their core components can detect high-energy radiation from the solar system, the Milky Way, and beyond, including charged particles, neutral particles, and X-rays. For decades, research on scintillators has attracted widespread interest from the scientific and industrial communities, leading to rapid advancements in this field. However, with the expanding applications of high-energy rays, higher performance requirements are being placed on scintillators. Scintillators with higher light yield and shorter decay lifetimes have broad application prospects in the future. Therefore, a method to improve the high-energy ray detection performance of powdered scintillators is urgently needed. Summary of the Invention

[0003] To address the aforementioned shortcomings, the present invention aims to provide a method for improving the high-energy ray detection performance of powdered scintillators.

[0004] To achieve the above objectives, the technical solution provided by this invention is as follows:

[0005] A method for improving the high-energy ray detection performance of powdered scintillators includes the following steps:

[0006] (1) Prepare scintillator material by crushing and grinding the scintillator material to obtain scintillator particles with a particle size of 1-10 μm;

[0007] (2) The surface of the scintillator particles is completely or partially coated with a metal layer with a surface plasmon effect by thermal evaporation, electron beam evaporation, plasma sputtering or atomic layer deposition processes to obtain coated particles; the thickness of the metal layer is 0.01-50 nm.

[0008] (3) The coated particles are mixed with organic polymer materials and poured into the cavity of a mold for molding and curing. After curing, a scintillator sheet is made. The cavity depth of the mold is 1 mm, and the thickness of the scintillator sheet is 1 μm-1 mm.

[0009] (4) The scintillator plate is used to detect high-energy rays.

[0010] The beneficial effects of this invention are as follows: This invention rationally coats or partially covers the surface of scintillator particles with metallic materials. Based on the plasma effect of metallic materials, it can effectively improve the light yield of the scintillator and reduce its decay lifetime, thereby achieving the purpose of improving the scintillator's detection performance for high-energy rays. Moreover, the entire operation process is simple, convenient, and easy to implement. It can be applied to scintillator materials of various powder shapes and has a wide range of applications, such as nuclear medicine imaging, security inspection, industrial detection, and high-energy physics.

[0011] The present invention will be further described below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0012] Figure 1 This is a process flow diagram of the present invention.

[0013] Figure 2 This is a comparison chart of the net count rate of γ-rays for the scintillator sheet prepared in Embodiment 1 of the present invention and the uncoated ZnS:Ag.

[0014] Figure 3 This is a net count rate diagram of α rays for the scintillator sheet prepared in Embodiment 1 of the present invention.

[0015] Figure 4 This is a net count rate diagram of α rays for ZnS:Ag without Al coverage in Embodiment 1 of the present invention.

[0016] Figure 5 This is a comparison diagram of the attenuation lifetime of α-rays between the scintillator sheet prepared in Embodiment 1 of the present invention and ZnS:Ag without Al coverage. Detailed Implementation

[0017] Example 1:

[0018] A ZnS:Ag scintillator chip for detecting α and γ rays was prepared. 0.24 g of ZnS(Ag) powder was weighed and ground in a mortar for 30 min to obtain a particle size range of 3-10 micrometers. A 3 nm thick aluminum layer was then partially coated on the surface of the ZnS(Ag) powder using a thermal evaporation process.

[0019] Dissolve equal amounts of polymethyl methacrylate (PMMA) in 2 mL of dichloromethane. After the PMMA is completely dissolved, pour ZnS (Ag) powder coated with an aluminum layer into CH2Cl2 and mix well. Then pour the mixture into a mold with a cavity diameter of 25 mm and a depth of 1 mm. Let it stand overnight to allow the organic solution to evaporate completely, and then demold to obtain a scintillator sheet.

[0020] The obtained ZnS:Ag scintillator sheet was used to test α and γ rays.

[0021] Example 2:

[0022] Preparation of ZnS:Ag for neutron detection and 6 LiF scintillator sheet. Weigh 0.24 g of ZnS(Ag) powder and grind it in a mortar for 30 min to achieve a particle size range of 3-10 micrometers. Then, partially coat the surface of the ZnS(Ag) powder with a 16 nm thick aluminum layer using a thermal evaporation process. Finally, the aluminum-coated ZnS(Ag) powder is... 6 LiF was uniformly mixed to obtain a mixed powder. 6 The mass ratio of LiF to ZnS(Ag) powder is 1:2. 0.24g of polymethyl methacrylate (PMMA) is dissolved in 2mL of dichloromethane. After the PMMA is completely dissolved, the mixed powder is poured into CH2Cl2 and mixed evenly. The mixture is then poured into a mold with a cavity diameter of 25mm and a depth of 1mm. It is left to stand overnight to allow the organic solution to evaporate completely, and then demolded to obtain the scintillator sheet.

[0023] The obtained scintillator slices were used to measure neutrons.

[0024] Example 3:

[0025] A ZnS:Ag scintillator sheet for detecting α and γ rays was prepared. 0.24 g of ZnS(Ag) powder was weighed and ground in a mortar for 30 min to achieve a particle size range of 3-10 μm. A 24 nm thick aluminum layer was then deposited onto the surface of the ZnS(Ag) powder using a thermal evaporation process. An equal mass of polymethyl methacrylate (PMMA) was dissolved in 2 mL of dichloromethane. After complete dissolution, the aluminum-coated ZnS(Ag) powder was poured into CH2Cl2 and mixed thoroughly. The mixture was then poured into a mold with a cavity diameter of 25 mm and a depth of 1 mm. The mold was left to stand overnight to allow the organic solution to evaporate completely before demolding to obtain the scintillator sheet.

[0026] The obtained scintillator slices were used to measure alpha and gamma rays.

[0027] Example 4:

[0028] A CsI(Na) scintillator sheet for gamma-ray detection was prepared. CsI(Na) crystals were crushed and then ground into powder with a particle size of 3-10 micrometers using a ball mill. A 15 nm layer of metallic aluminum was uniformly coated onto the surface of the CsI(Na) powder using a thermal evaporation process. 0.24 g of PMMA was dissolved in 2 mL of dichloromethane. An equal mass of the aluminum-coated CsI(Na) powder was poured into CH2Cl2 and mixed thoroughly. The mixture was then poured into a mold with a cavity diameter of 25 mm and a depth of 1 mm. After standing overnight to allow the organic solvent to evaporate completely, the scintillator sheet was demolded.

[0029] The obtained scintillator slices were used to measure gamma rays.

[0030] The above embodiments are merely preferred embodiments of the present invention. The present invention cannot list all embodiments. Any technical solution that adopts one of the above embodiments, or any equivalent changes made based on the above embodiments, are within the protection scope of the present invention.

[0031] The present invention rationally coats or partially covers the surface of scintillator particles with metallic materials. Based on the plasma effect of metallic materials, it can effectively increase the light yield of scintillators and reduce their decay lifetime, thereby improving the scintillator's detection performance for high-energy rays.

[0032] Taking Example 1 as an example, see Figure 2 The comparison of the net count rate of γ-rays for the ZnS:Ag scintillator sheet and the uncoated Al scintillator sheet in Example 1 shows that, in this example, the light yield of ZnS(Ag) for γ-rays increased fourfold after being coated with 3 nm of Al. See also... Figure 3 and Figure 4 , Figure 3 The net count rate of the ZnS:Ag scintillator slice without Al coverage is given. The area of ​​the graph formed by ZnS:Ag and the coordinate axes is 0.00307. Figure 4 The net count rate of the Al-coated ZnS(Ag) scintillator sheet is given. The area of ​​the graph formed by 3nm Al@ZnS:Ag and the coordinate axes is 0.00628, indicating that the ZnS:Ag surface coating doubled the alpha-ray yield. See also Figure 5 A comparison of the attenuation lifetimes of ZnS:Ag scintillator sheets without Al coating and 3nm Al@ZnS:Ag scintillator sheets for alpha rays shows that the 3nm Al@ZnS:Ag attenuates faster than ZnS:Ag. This invention leverages the plasma effect of metallic materials to enhance the light yield and attenuation lifetime of powdered scintillator materials for high-energy rays, thereby improving the detection performance of scintillator materials. It has broad application prospects in fields utilizing high-energy rays, such as nuclear medicine imaging, security inspection, industrial detection, and high-energy physics.

[0033] Based on the disclosure and teachings of the above specification, those skilled in the art can make changes and modifications to the above embodiments. Therefore, the present invention is not limited to the specific embodiments disclosed and described above, and some modifications and changes to the present invention should also fall within the protection scope of the claims of the present invention. Furthermore, although some specific terms are used in this specification, these terms are only for convenience of explanation and do not constitute any limitation on the present invention. Other methods and products obtained by using the same or similar methods are all within the protection scope of the present invention.

Claims

1. A method for improving the detection performance of powdered scintillators for high-energy rays, characterized in that: It includes the following steps: (1) Prepare scintillator material by crushing and grinding the scintillator material to obtain scintillator particles with a particle size of 1-10 μm; (2) Coating the surface of the scintillator particles with a metal layer having a surface plasma effect to obtain coated particles; (3) The coated particles are mixed with organic polymer materials to form a scintillator sheet; (4) The scintillator plate is used to detect high-energy rays; The thickness of the metal layer is 0.01-50 nm.

2. The method for improving the high-energy ray detection performance of powdered scintillators according to claim 1, characterized in that: The surface of the scintillator particles is coated with a metal layer having a surface plasmon effect by thermal evaporation, electron beam evaporation, plasma sputtering, or atomic layer deposition processes.

3. The method for improving the high-energy ray detection performance of powdered scintillators according to claim 1, characterized in that: The surface of the scintillator particles is completely or partially covered by the metal layer.

4. The method for improving the detection performance of powdered scintillator against high-energy rays according to claim 1, wherein the scintillator material is ZnS(Ag) powder or CsI(Na) crystal.

5. The method for improving the detection performance of powdered scintillator against high-energy rays according to claim 1, wherein the metal layer is an aluminum layer.

6. The method for improving the detection performance of powdered scintillator against high-energy rays according to claim 1, wherein in step (3), the coated particles are mixed with organic polymer materials and poured into the cavity of a mold for molding and curing, and after curing, a scintillator sheet is made.

7. The method for improving the detection performance of powdered scintillator against high-energy rays according to claim 6, wherein the cavity depth of the mold is 1 mm.

8. The method for improving the detection performance of powdered scintillator against high-energy rays according to claim 1, wherein the thickness of the scintillator sheet is 1µm-1mm.

9. A scintillator sheet, characterized in that, It is the scintillator sheet as described in any one of claims 1-8.

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