An indium-based chloride scintillation crystal and a method of making the same

Abstract

The present application relates to the technical field of scintillation crystal preparation, in particular to an indium-based chloride scintillation crystal and a preparation method thereof. The indium-based chloride scintillation crystal is prepared by using a quartz crucible with a necked seed tube and a crucible lowering method. Through adjustment of process parameters, the non-uniform melting characteristics of raw materials can be overcome, defects caused by phase transition can be improved, and the performance can be adjusted according to the required performance. Finally, the indium-based chloride scintillation crystal Cs2LiIn 1‑x Ce x Cl6.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of scintillation crystal preparation, in particular to an indium-based chloride scintillation crystal and a preparation method thereof. BACKGROUND

[0002] The information disclosed in this Background section is only for the purpose of increasing an understanding of the general background of the application and does not necessarily constitute an acknowledgement or any form of suggestion that this information forms part of the prior art already known to a person of ordinary skill in the art.

[0003] In recent years, with the widespread use of radioactive materials, the application of thermal neutron-gamma dual readout detectors capable of simultaneously detecting and effectively discriminating thermal neutrons and gamma rays in preventing nuclear proliferation, nuclear leakage, security checks and nuclear radiation environmental protection is becoming increasingly important. The thermal neutron-gamma dual readout detector widely used at present generally contains two detectors, one is a thermal neutron detector, such as 3 He gas tube; the other is a gamma ray detector, such as a NaI:Tl crystal detector; both detectors work together to simultaneously detect thermal neutrons and gamma rays. Thermal neutron detection mainly utilizes the reaction of neutrons with specific isotopes (such as 3 He, 6 Li and 10 B) in thermal neutron detection materials to release alpha particles, thereby indirectly detecting neutrons; gamma ray detection mainly utilizes the luminescence of scintillation crystals activated by gamma rays for detection through energy analysis. There are many types of scintillation crystals that can be used to detect gamma rays, which are also the main content of scintillation crystal research; while thermal neutron detection requires materials containing 3 He, 6 Li or 10 B, etc., so there are much fewer types of materials, and the development is slow. The traditional thermal neutron detector is a 3 He proportional counter tube, but in recent years, 3 He resources are close to exhaustion, and existing resources cannot meet the needs.

[0004] At present, Cs2LiYCl6(CLYC) crystals have excellent performance in the detection field, which can achieve an energy resolution of 7% at 662KeV and effectively discriminate thermal neutrons and gamma rays, but their application is limited due to their difficulty in preparation, easy deliquescence, high price and size limitation; Yb:YAG is used for neutron detection with fast response time, but in the mixed field of thermal neutrons and gamma rays, the performance of the crystal material is degraded due to irradiation; the best alpha particle light output to gamma ray light output ratio of Li6Gd(BO3)3 single crystal is only 0.16, which cannot effectively distinguish particles in the mixed field.

[0005] Therefore, it is urgent to develop a neutron detector with large size, radiation resistance, and strong discrimination ability for thermal neutrons and gamma rays. SUMMARY

[0006] In order to overcome the above problems, the present application provides an indium-based chloride scintillation crystal and a preparation method thereof. 1-x Ce x Cl6.

[0007] To achieve the above technical purposes, the present application adopts the following technical solutions.

[0008] In a first aspect, the present application provides an indium-based chloride scintillation crystal, which has a chemical formula of Cs2LiIn 1-x Ce x Cl6, wherein the value range of x is 0.0001≤x≤0.015.

[0009] The cerium ions in the indium-based chloride scintillation crystal, which play a role in luminescence, exist in the form of +3 valence, and the cerium ions randomly occupy the In 3+ ion lattice sites to form luminescence centers.

[0010] In a second aspect, the present application provides a preparation method of the indium-based chloride scintillation crystal of the first aspect, which comprises the following steps.

[0011] (1) According to the chemical formula Cs2LiIn 1-x Ce x Cl6 of the indium-based chloride scintillation crystal, each raw material is weighed;

[0012] (2) Under the atmosphere of inert gas, each raw material is ground into powder, and all the raw material powders are uniformly mixed;

[0013] (3) The mixed raw material powder is placed in a defined quartz crucible, the quartz crucible is evacuated to a vacuum state, and then the quartz crucible is sealed;

[0014] (4) The sealed quartz crucible is placed in a crucible lowering furnace, the temperature is heated to 700-750℃, and the temperature is maintained for 3-4h, then the temperature is lowered to 380-400℃, and the temperature is maintained for 3-4h; the temperature rising and lowering process is repeated for 3-4 times, then the temperature is lowered to room temperature, and a Cs2LiIn 1-x Ce x Cl6 polycrystal is formed;

[0015] (5) The Cs2LiIn 1-x Ce xThe quartz crucible of C16 polycrystalline material is vertically placed in a vertically arranged crucible descending furnace, the temperature is raised to 610-650 DEG C, and the temperature is kept for 9.5-12 hours; a descending program is set, the quartz crucible passes through a temperature gradient zone of 16-25 DEG C / cm at a descending rate of 0.25-0.4 mm / h, and the melt crystallization is completed;

[0016] (6) annealing the crystal to obtain the indium-based chloride scintillation crystal.

[0017] The present application has the advantages that:

[0018] (1) The present application relates to the technical field of scintillation crystal preparation, and particularly relates to an indium-based chloride scintillation crystal and a preparation method thereof. The quartz crucible with a necked seed tube is used to prepare the indium-based chloride scintillation crystal by the crucible descending method, the non-uniform melting characteristics of the raw material can be overcome by adjusting the process parameters, the defects caused by phase transition can be improved, and the indium-based chloride scintillation crystal Cs2LiIn 1-x Ce x Cl6 with good crystallization performance, large size and good optical performance can be finally prepared.

[0019] (2) The indium-based chloride scintillation crystal Cs2LiIn 1-x Ce x Cl6 prepared by the present application has a hexagonal crystal system, and has a broad development prospect in the field of radiation detection and ultraviolet photoelectricity.

[0020] (3) The raw material in the present application includes CsCl, LiCl, InCl3 and CeCl3, and the crystallization of the crystal can be improved by using excessive LiCl due to the non-uniform melting characteristics.

[0021] (4) The special structure quartz crucible with a necked seed tube can eliminate the crystal nucleus, prevent the spontaneous nucleation from generating seed crystal particles with poor quality and non-ideal growth crystallization direction, and further cause more defects and cracking of the crystal growth.

[0022] (5) It is found in the experiment that the setting of the temperature gradient zone will affect the quality of the crystal. Specifically, a too large temperature gradient, such as greater than 25 DEG C / cm, will cause serious cracking of the crystal and reduce the quality of the crystal; a too small temperature gradient, such as less than 16 DEG C / cm, will cause poor crystallization of the crystal and cannot form a crystal.

[0023] Meanwhile, the setting of the cooling rate will also affect the quality of the crystal. A too fast cooling rate, such as greater than 10 DEG C / h, will cause the thermal stress to be released quickly and cause cracking; a too slow cooling rate, such as less than 5 DEG C / h, will cause the quartz crucible to be easily cracked due to the high temperature state for a long time and the high gas pressure in the quartz crucible. BRIEF DESCRIPTION OF DRAWINGS

[0024] The accompanying drawings, which form a part of this specification, are included to provide a further understanding of the application, and are incorporated in and constitute a part of this specification. The embodiments of the application, and their

[0025] Figure 1 A photograph of a quartz crucible with a necked seed tube.

[0026] Figure 2 A schematic diagram of the structure of a quartz crucible with a necked seed tube.

[0027] Figure 3 A detailed dimension drawing of a quartz crucible with a necked seed tube used in Example 2 and Comparative Examples 2-3.

[0028] Figure 4 Photographs of crystals, where (a) is an indium-based chloride scintillation crystal Cs2LiIn 1- x Ce x Cl6, (b) is a photograph of the crystal prepared in Comparative Example 1, (c) is a photograph of the crystal prepared in Comparative Example 2; (d) is a photograph of the crystal prepared in Comparative Example 3.

[0029] Figure 5 XRD pattern of an indium-based chloride scintillation crystal Cs2LiIn 1-x Ce x Cl6prepared in Example 2.

[0030] Figure 6 UV-Vis test pattern of an indium-based chloride scintillation crystal Cs2LiIn 1-x Ce x Cl6prepared in Example 2.

[0031] Figure 7 Photoluminescence spectrum test results of an indium-based chloride scintillation crystal Cs2LiIn 1-x Ce x Cl6prepared in Example 2.

[0032] Figure 8 A photograph of a quartz crucible with only a seed tube structure used in Comparative Example 1. DETAILED DESCRIPTION

[0033] It should be noted that the following detailed description is exemplary in nature, and is intended to provide further description of the application. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

[0034] It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments in accordance with the present application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and / or "comprising," when used in this specification, specify the presence of stated features, steps, operations, elements, components, and / or groups thereof, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and / or groups thereof.

[0035] In a first exemplary embodiment of the present application, there is provided an indium-based chloride scintillation crystal having a chemical formula of: Cs2LiIn 1-x Ce x Cl6, wherein x is in a range of 0.0001≤x≤0.015.

[0036] The cerium ions, which play a role in luminescence in the indium-based chloride scintillation crystal, exist in a +3 valence form, and the cerium ions randomly occupy In 3+ ion lattice sites to form luminescence centers.

[0037] In a second exemplary embodiment of the present application, there is provided a method of manufacturing the indium-based chloride scintillation crystal of the first aspect, including the following steps:

[0038] (1) Each raw material is weighed according to the chemical formula of the indium-based chloride scintillation crystal Cs2LiIn 1-x Ce x Cl6;

[0039] (2) Each raw material is ground into a powder in an atmosphere of an inert gas, and all of the raw material powders are mixed uniformly;

[0040] (3) The mixed raw material powders are placed in a defined quartz crucible, the quartz crucible is evacuated, and then the quartz crucible is sealed;

[0041] (4) The sealed quartz crucible is placed in a crucible lowering furnace, the temperature is heated to 700-750°C, and then maintained for 3-4 hours, and then the temperature is lowered to 380-400°C, and then maintained for 3-4 hours; the process of heating and lowering the temperature is repeated 3-4 times, and then the temperature is lowered to room temperature, to form Cs2LiIn 1-x Ce x Cl6 polycrystal;

[0042] (5) The quartz crucible containing the Cs2LiIn 1-x Ce x Cl6 polycrystal is placed vertically in a vertically arranged crucible lowering furnace, the temperature is raised to 610-650°C, and then maintained for 9.5-12 hours; a lowering program is set, so that the quartz crucible passes through a temperature gradient zone of 16-25°C / cm at a lowering rate of 0.25-0.4 mm / h, to complete the melt crystallization;

[0043] (6) annealing the crystal to obtain the indium-based chloride scintillation crystal.

[0044] In one or more embodiments, in step (1), the raw material comprises CsCl, LiCl, InCl3 and CeCl3, wherein the molar ratio of CsCl, LiCl, InCl3 and CeCl3 is 2:(1-1.05):(1-x):x, wherein x is in the range of 0.0001≤x≤0.015. Using excess LiCl can improve the crystallinity of the crystal.

[0045] In one or more embodiments, in step (3), the defined quartz crucible is a quartz crucible with a necked seed tube, which comprises a quartz crucible body and a necked seed tube connected in sequence, wherein the necked seed tube comprises a necked zone and a seed zone connected in sequence.

[0046] The seed zone comprises a first seed zone, a variable-diameter zone and a second seed zone connected in sequence.

[0047] The quartz crucible body and the necked seed tube are integrally formed.

[0048] Preferably, the inner diameter of the quartz crucible body is greater than that of the seed zone; the necked zone connecting one end of the quartz crucible body has the same inner diameter as the quartz crucible body; the necked zone connecting the seed zone has the same inner diameter as the seed zone; and the inner diameter of the necked zone gradually decreases from the one end connecting the quartz crucible body to the one end connecting the seed zone.

[0049] Preferably, the length ratio of the quartz crucible body, the necked zone and the seed zone is (15.5-16.5):3:6, preferably 16:3:6.

[0050] Preferably, the length ratio of the first seed zone, the variable-diameter zone and the second seed zone is 4:(0.8-1.2):10, preferably 4:1:10.

[0051] Preferably, the inner diameters of the first seed zone and the second seed zone are the same; and the inner diameter ratio of the quartz crucible body to the first seed zone is (2.4-2.6):1, preferably 2.5:1.

[0052] Preferably, the inner diameter of the variable-diameter zone is smaller than that of the first seed zone and the second seed zone; and the inner diameter of the variable-diameter zone is smoothly transitioned.

[0053] Further preferably, the inner diameter ratio of the variable-diameter zone to the first seed zone is 2:(0.8-1.2), preferably 2:1.

[0054] In one or more embodiments, in step (4), the temperature is heated at a rate of 85-95°C / h, preferably 90°C / h.

[0055] In one or more embodiments, in step (4), the temperature is cooled at a rate of 55-65°C / h, preferably 60°C / h, to 380-400°C.

[0056] In one or more embodiments, in step (4), the temperature is cooled at a rate of 18-22°C / h, preferably 20°C / h, to room temperature.

[0057] In one or more embodiments, in step (5), the temperature is heated at a rate of 58-65°C / h, preferably 60°C / h, to 610-650°C.

[0058] In one or more embodiments, in step (6), the annealing process comprises: cooling the upper temperature zone to 445-455°C; heating the lower temperature zone to 445-455°C; maintaining the temperature of the middle temperature zone at 350-360°C during the temperature adjustment of the upper and lower temperature zones; and then simultaneously cooling the upper and lower temperature zones to 395-405°C and heating the middle temperature zone to 395-405°C, and then simultaneously maintaining the three temperature zones at 395-405°C for 1.5-2.5h, and then cooling to room temperature to obtain the indium-based chloride scintillation crystal.

[0059] Preferably, in the annealing process, the heating or cooling rate of the three temperature zones is the same, and is 5-8°C / h, preferably 5°C / h.

[0060] In order to enable those skilled in the art to more clearly understand the technical solutions of the present application, the technical solutions of the present application will be described in detail below with specific examples.

[0061] Example 1

[0062] According to the characteristics of crystal spontaneous nucleation, in order to obtain higher quality seed crystal grains, a quartz crucible with a necked seed crystal tube structure is designed and customized, and the neck is designed to eliminate redundant crystal nuclei in the growth direction. Figure 1 The actual picture of the quartz crucible with the necked seed crystal tube is as follows, Figure 2 The structure schematic diagram of the quartz crucible with the necked seed crystal tube is as follows.

[0063] As shown in the drawings, Figure 2 A quartz crucible with a necked seed crystal tube includes a quartz crucible body 1 and a necked seed crystal tube which are sequentially connected, and the necked seed crystal tube includes a necked zone 2 and a seed crystal zone which are sequentially connected.

[0064] The seed crystal zone includes a first seed crystal zone 3, a variable diameter zone 4 and a second seed crystal zone 5 which are sequentially connected.

[0065] The quartz crucible body 1 and the necked seed tube are integrally formed.

[0066] The inner diameter of the quartz crucible body 1 is greater than that of the seed zone; the inner diameter of the necked zone 2 connecting one end of the quartz crucible body 1 is the same as that of the quartz crucible body 1; the inner diameter of the necked zone 2 connecting one end of the seed zone is the same as that of the seed zone; and the inner diameter of the necked zone 2 gradually decreases from the one end connecting the quartz crucible body 1 to the one end connecting the seed zone.

[0067] The length ratio of the quartz crucible body 1, the necked zone 2 and the seed zone is (15.5-16.5):3:6, preferably 16:3:6.

[0068] The length ratio of the first seed zone 3, the variable-diameter zone 4 and the second seed zone 5 is 4:(0.8-1.2):10, preferably 4:1:10.

[0069] The inner diameter of the first seed zone 3 is the same as that of the second seed zone 5; and the inner diameter ratio of the quartz crucible body 1 to the first seed zone 3 is (2.4-2.6):1, preferably 2.5:1.

[0070] The inner diameter of the variable-diameter zone 4 is smaller than that of the first seed zone 3 and the second seed zone 5; and the inner diameter of the variable-diameter zone 4 is smoothly transitioned. The inner diameter ratio of the variable-diameter zone 4 to the first seed zone 3 is 2:(0.8-1.2), preferably 2:1.

[0071] The specific dimensions of the quartz crucible with a necked seed tube used in the following Example 2 and Comparative Examples 2-3 are shown in Table 1. Figure 3 Table 1

[0072] Example 2

[0073] In-based chloride scintillation crystal Cs2LiIn 1-x Ce x Cl6:

[0074] (1) Pretreatment of the quartz crucible with a necked seed tube:

[0075] Deionized water was used for washing to remove impurities and stains attached to the surface, followed by ultrasonic cleaning. Specifically, deionized water was injected into the quartz crucible, which was placed on a filter screen in a water bath ultrasonic cleaning instrument to prevent the seed tube from directly contacting the instrument during ultrasonic cleaning, thereby preventing the influence of ultrasonic vibration on the quartz crucible. The power of ultrasonic cleaning was 180 w, and the time was 30 min. The above cleaning process was repeated twice.

[0076] The inner cavity of the quartz crucible washed with deionized water is injected with anhydrous ethanol, and the opening is sealed with plastic wrap to prevent external dust from contacting the lumen. Ultrasonic cleaning is performed in a water bath ultrasonic cleaner with a power of 180 w for 30 min. The above cleaning process is repeated twice.

[0077] The quartz crucible washed with anhydrous ethanol is transferred to a drying oven and dried at 60°C for 24 h to ensure that the liquid on the wall is evaporated without residue.

[0078] (2) Raw material pretreatment:

[0079] In the glove box filled with inert gas, the chemical formula of the indium-based chloride scintillation crystal is Cs2LiIn 1-x Ce x Cl6, and the purity of CsCl, LiCl, InCl3, and 1.5% mol CeCl3 is greater than 99.99%. Due to the non-uniform melting characteristics, 5% mol of LiCl is selected as an excess in the selection of raw materials, and the rest of the raw materials are stoichiometrically matched. Each raw material is ground into powder, and all the raw material powders are mixed uniformly. The mixed raw material powder is loaded into the quartz crucible of step (1). To remove water and oxygen in the raw materials and the quartz crucible, it is placed in a vacuum at 150°C to a vacuum degree less than 6×10 -3 Pa. Then, using a hydrogen-oxygen torch, it is sealed in a continuous ionization vacuum state with a rotation speed of 20 r / min.

[0080] (3) The sealed quartz crucible in step (2) is placed in a crucible lowering furnace, and the temperature is raised to 700°C at a rate of 90°C / h to ensure that the raw materials are completely melted, and then maintained for 3 h. The temperature is lowered to 400°C at a rate of 60°C / h until the polycrystalline material is completely solidified, and then maintained for 3 h. The temperature raising and lowering process is repeated three times to complete the aging of the polycrystalline material. The temperature is lowered to room temperature at a rate of 20°C / h to form a Cs2LiIn 1-x Ce x Cl6 polycrystalline material.

[0081] (4) The quartz crucible containing the Cs2LiIn 1-x Ce x Cl6 polycrystalline material is placed vertically in a vertically arranged crucible lowering furnace, and the temperature is raised to 620°C at a rate of 60°C / h, and then maintained for 10 h to ensure that the polycrystalline material is completely melted. The lowering program is set so that the quartz crucible passes through a temperature gradient of 16°C / cm at a lowering rate of 0.4 mm / h. The lowering rate and temperature gradient match the ion migration rate in the phase transition, and the lowering is automatically stopped when the material in the cavity reaches the position where the temperature gradient is located, and the next step is entered.

[0082] (5) After the temperature in step (4) stops decreasing, the program automatically enters the cooling process. The upper temperature zone is cooled from 627°C to 450°C at a cooling rate of 5°C / h; the lower temperature zone is heated from 335°C to 450°C at a heating rate of 5°C / h. During this period, the temperature of the middle temperature zone is maintained at 356°C. After preliminary testing, this annealing process can ensure that the grown single crystal will not be remelted twice. Subsequently, the upper and lower temperature zones are cooled to 400°C at the same time, and the middle temperature zone is heated to 400°C. The three temperature zones are kept warm for 2 hours at the same cooling rate of 5°C / h to obtain the indium chloride scintillation crystal Cs2LiIn 1-x Ce x Cl6.

[0083] The indium-based chloride scintillating crystal Cs2LiIn prepared in this example 1-x Ce x The physical picture of Cl6 is as follows Figure 4 As shown in (a).

[0084] The indium chloride scintillating crystal Cs2LiIn prepared in this example 1-x Ce x Take a good quality uniform block from the first seed crystal area, necking area and quartz crucible body area of ​​Cl6 and grind it thoroughly, and then perform XRD test. The test results are as follows: Figure 5 As shown, the structural formula of the indium chloride scintillating crystal prepared in this embodiment is finally determined to be Cs2LiIn 0.99 Ce 0.01 Cl6.

[0085] The indium chloride scintillator crystal prepared in this example was subjected to transmittance test and UV-Vis test. The transparent area block with equal diameter was cut, ground and polished to make a 7mm×5mm×2mm rectangular ingot. The polished ingot was placed in the UV spectrophotometer. The test results are shown in Figure 2. Figure 6 As shown. This scintillation crystal can achieve a high transmittance. The 260-325nm band is Ce 3+ characteristic absorption peak of Ce 3+ Successfully doped into Cs2LiInCl6 crystal.

[0086] The indium chloride scintillator crystal prepared in this example was subjected to photoluminescence spectrum testing. The transparent area in the crucible body was cut, ground, and polished to form a 7mm×5mm×2mm rectangular ingot. The polished ingot was placed in a fluorescence spectrometer. The test results are shown in Figure 2. Figure 7 As shown. Under 340nm excitation, the crystal shows a double peak emission at 375nm and 410nm, which belongs to Ce 3+ 5d-4f transition.

[0087] Comparative Example 1

[0088] Comparative Example 2 Figure 8 Comparative Example 2 Comparative Example 2

[0089] Comparative Example 2 Figure 4 Comparative Example 2 Comparative Example 2

[0090] Comparative Example 2 Comparative Example 2

[0091] Comparative Example 2 1-x Comparative Example 2 x Comparative Example 2 Comparative Example 2

[0092] Comparative Example 2 Figure 4 Comparative Example 2 Comparative Example 2

[0093] Comparative Example 2 Comparative Example 2

[0094] Comparative Example 2 Comparative Example 2

[0095] Comparative Example 2 Figure 4 Comparative Example 2 Comparative Example 2

[0096] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method of making an indium-based chloride scintillation crystal, comprising: The indium-based chloride scintillation crystal has a chemical formula of: Cs2LiIn 1-x Ce x Cl6, wherein x has a value in a range of 0.0001≤x≤0.015; The preparation method of the indium-based chloride scintillation crystal comprises the following steps: (1) According to the chemical formula of indium-based chloride scintillation crystal Cs2LiIn 1-x Ce x Cl6Each raw material, including excess LiCl, is weighed. (2) under the atmosphere of inert gas, grinding each raw material into powder, and mixing all the raw material powders uniformly; (3) placing the mixed raw material powder into a quartz crucible with a necked seed tube, vacuumizing the quartz crucible with the necked seed tube, and then sealing the quartz crucible with the necked seed tube; (4) Put the sealed quartz crucible with the necked seed tube into the crucible lowering furnace, heat the temperature to 700-750 °C, maintain for 3-4 h, then reduce the temperature to 380-400 °C, maintain for 3-4 h; repeat the process of temperature rising and reducing for 3-4 times, then reduce the temperature to room temperature, to form Cs2LiIn 1-x Ce x Cl6 polycrystalline material; (5) Containing Cs2LiIn 1-x Ce x A quartz crucible containing a constricted seed tube of Cl6 polycrystalline material is placed vertically in a vertically arranged crucible descending furnace. The temperature is raised to 610-650°C and held for 9.5-12 hours. A descending program is set so that the quartz crucible containing the constricted seed tube descends at a rate of 0.25-0.4 mm / h through a temperature gradient of 16-25°C / cm to complete melt crystallization. (6) annealing the crystal to obtain the indium-based chloride scintillation crystal.

2. The production method according to claim 1, wherein In step (1), the raw materials include CsCl, excess LiCl, InCl3 and CeCl3, wherein the molar ratio of CsCl, excess LiCl, InCl3 and CeCl3 is 2:(1-1.05):(1-x):x, and the value range of x is 0.0001≤x≤0.

015.

3. The production method according to claim 1, wherein In step (3), the quartz crucible with the necked seed tube comprises a quartz crucible body and a necked seed tube which are sequentially communicated, and the necked seed tube comprises a necked zone and a seed crystal zone which are sequentially communicated. The seed crystal zone comprises a first seed crystal zone, a variable-diameter zone and a second seed crystal zone which are sequentially communicated. The quartz crucible body and the necked seed tube are integrally formed.

4. The production method according to claim 3, wherein The inner diameter of the quartz crucible body is larger than that of the seed crystal zone; the necked zone connecting one end of the quartz crucible body has the same inner diameter as the quartz crucible body; the necked zone connecting the seed crystal zone has the same inner diameter as the seed crystal zone; and the inner diameter of the necked zone gradually decreases from the one end connecting the quartz crucible body to the one end connecting the seed crystal zone. Alternatively, the length ratio of the quartz crucible body, the necked zone and the seed crystal zone is (15.5-16.5):3:

6.

5. The production method according to claim 4, wherein The length ratio of the quartz crucible body, the necked zone and the seed crystal zone is 16:3:

6.

6. The production method according to claim 3, wherein The length ratio of the first seed crystal zone, the variable-diameter zone and the second seed crystal zone is 4:(0.8-1.2):

10. Alternatively, the inner diameters of the first seed crystal zone and the second seed crystal zone are the same; and the inner diameter ratio of the quartz crucible body to the first seed crystal zone is (2.4-2.6):

1. Alternatively, the inner diameter of the variable-diameter zone is smaller than that of the first seed crystal zone and the second seed crystal zone; and the inner diameter of the variable-diameter zone is smoothly transitioned.

7. The production method according to claim 6, wherein The length ratio of the first seed crystal zone, the variable-diameter zone and the second seed crystal zone is 4:1:

10.

8. The production method according to claim 6, wherein The inner diameter ratio of the quartz crucible body to the first seed crystal zone is 2.5:

1.

9. The production method according to claim 6, wherein The inner diameter ratio of the variable-diameter zone to the first seed crystal zone is 2:(0.8-1.2).

10. The production method according to claim 9, wherein The inner diameter ratio of the variable-diameter zone to the first seed crystal zone is 2:

1.

11. The production method according to claim 2, wherein In step (4), the temperature heating process has a temperature rising rate of 85-95 ℃ / h.

12. The production method according to claim 11, wherein In step (4), the temperature heating process has a temperature rising rate of 90 ℃ / h.

13. The production method according to claim 2, wherein In step (4), the temperature decreasing process to 380-400 ℃ has a temperature decreasing rate of 55-65 ℃ / h.

14. The production method according to claim 13, wherein In step (4), the temperature decreasing process to 380-400 ℃ has a temperature decreasing rate of 60 ℃ / h.

15. The production method according to claim 2, wherein In step (4), the temperature decreasing process to room temperature has a temperature decreasing rate of 18-22 ℃ / h. Alternatively, in step (5), the temperature rising process to 610-650 ℃ has a temperature rising rate of 58-65 ℃ / h.

16. The production method according to claim 15, wherein In step (4), the temperature is decreased to room temperature at a rate of 20 ℃ / h.

17. The production method according to claim 15, wherein In step (4), the temperature is increased to 610~650 ℃ at a rate of 60 ℃ / h.

18. The production method according to claim 2, wherein In step (6), the annealing process comprises: decreasing the temperature in the upper temperature zone to 445~455 ℃; increasing the temperature in the lower temperature zone to 445~455 ℃; in the process of adjusting the temperature in the upper temperature zone and the lower temperature zone, the temperature in the middle temperature zone is maintained at 350~360 ℃; then the upper and lower temperature zones are simultaneously decreased to 395~405 ℃, and the middle temperature zone is increased to 395~405 ℃; after that, the three temperature zones are simultaneously maintained at 395~405 ℃ for 1.5~2.5 h, and then decreased to room temperature to obtain the indium-based chloride scintillation crystal.

19. The production method according to claim 18, wherein In the annealing process, the temperature increasing or decreasing rate of the three temperature zones is the same, and is 5~8 ℃ / h.

20. The production method according to claim 19, wherein In the annealing process, the temperature increasing or decreasing rate of the three temperature zones is the same, and is 5 ℃ / h.

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