KR20200090357A - Zeolite scintillator containing titanium chloride and its producing method - Google Patents

Abstract

The present invention relates to a zeolite scintillator comprising titanium chloride, and a method of producing the same, and more specifically, to a novel zeolite scintillator represented by D_xCs_yE_z-zeolite, a method of producing the zeolite scintillator, and a method of utilizing the same. The zeolite scintillator comprising titanium chloride and the method of producing the same provided in the present invention, by using an adsorption method using gas-phase reactions, can incorporate titanium, which is difficult to incorporate into zeolite by existing liquid-phase ion-exchange methods, and thus increase the cost-effectiveness of a zeolite scintillator, reduce the number of preparation steps, and achieve excellent flash effect and light emission yield.

Description

Zeolite scintillator containing titanium chloride and its producing method

The present invention relates to a zeolite scintillator comprising titanium chloride and a method for manufacturing the same, and in detail, a novel zeolite scintillator and zeolite scintillator represented by D _x Cs _y E _z -zeolite, and a method for using the same It is about.

Zeolite, a microporous aluminum silicate, is mainly composed of silicon, oxygen, and aluminum, and also contains a small amount of metals. It is used as an adsorbent or catalyst because it can selectively separate small-sized gas or liquid molecules according to their size and shape using very regularly arranged micro-pores in the structure, and it is used as an adsorbent or catalyst. It plays the role of ion-exchange in the field and is also used to separate molecules of a certain size and shape.

A scintillator is a substance that flashes by radiation. That is, it refers to a substance that can play a role in converting high energy radiation into visible light that cannot be seen by the human eye outside the visible light region. Scintillators are used in medical fields such as computed tomography (CT), positron emission tomography (PET), and cancer treatment using selective nanoparticle scintillators. In addition, scintillators are used in various fields such as hydrate search, non-destructive testing, and particle detection of high-energy physics, and can also be used to measure environmental pollution caused by radioactivity.

Environmental pollution has been seriously caused by artificial radiation such as radioactive fallout or radioactive waste discharged from nuclear facilities in recent nuclear tests, and the materials that cause it are nuclear fission products, cooling water containing various induced radioactivity, radioactive gases, and radioactivity There is dirt, waste liquid, etc. to which the substance adhered. In addition, there are many types of radionuclides that are contained. In particular, the risks are high due to the effects of cesium-137 ( ¹³⁷ Cs) and strontium-90 ( ⁹⁰ Sr) on the body, and radioactivity of transition elements such as iron, manganese, and cobalt Isotopes are prone to binding and enrichment with proteins in living organisms, and have emerged as a serious problem in terms of environmental pollution.

Accordingly,'Japanese Registered Publication No. 6302634' provides a method of separating and removing radioactive cesium from wastewater containing radioactive cesium and storing it highly concentrated, but it is adsorbed to zeolite by applying voltage and electrodialysis. This is complicated and difficult to implement, and there is a problem that only simple separation and removal is possible rather than measuring radioactive contaminants.

JP 6302634 B2

Jong-Jin Kim, Research on the manufacture and structure of FAU-zeolite containing Ga and In using vapor ion exchange method (VPIE), Graduate School of Kyungpook National University (2014.12.)

In order to solve the above problems, an object of the present invention is to provide a zeolite scintillator represented by D _x Cs _y E _z -zeolite.

It is also an object to provide a method for manufacturing a zeolite scintillator.

In addition, an object of the present invention is to provide an environmental radioactive material measuring device characterized in that it is made of a zeolite scintillator.

The present invention to solve the above object,

A zeolite scintillator represented by the following formula 1 is provided:

[Equation 1]

D _x Cs _y E _z -zeolite

D is titanium (Ti), E is one or more selected from the group consisting of fluorine (F), chlorine (Choloride, Cl), bromine (Bromine, Br), and iodine (Iodine, I) ,

x, y, and z means the number of ions contained in the unit cell, which is the most basic repeating unit constituting the zeolite,

x is 0.02 to 0.15, y is 4.00 to 8.00, z is 0.01 to 0.09.

D is titanium (Ti), E is chlorine (Choloride, Cl), and titanium and chlorine are connected by ionic bonds to form a complex in the form of an octahedron, and are arranged in a three-dimensionally connected structure. .

In the zeolite scintillator, cesium is introduced as an extraframewok ion into the framework of the zeolite, and the cesium and chlorine are connected by forming ionic bonds.

In addition, titanium and chlorine are arranged in the center of the space formed by the skeleton of the cesium ion-exchanged zeolite.

The zeolite scintillator shows an emission spectrum between 360 nm and 700 nm by radiation, and a maximum emission at a wavelength of 450 to 495 nm.

The present invention to solve the above other object,

Preparing a cesium ion exchanged zeolite; And

Including the step of forming a zeolite scintillator by reacting the cesium ion-exchanged zeolite and titanium chloride vapor at room temperature through Vapor Phase Ion Exchange (VPIE).

In the reacting step,

It provides a method for producing a zeolite scintillator, characterized in that the titanium chloride is ion-bonded with cesium of the cesium ion-exchanged zeolite, and is disposed in the center of the space formed through the skeleton of the cesium ion-exchanged zeolite.

The step of preparing a cesium ion-exchanged zeolite is performed through a liquid phase ion exchange method (LPIE).

In titanium chloride, Ti ⁴⁺ and Cl ⁻ are connected by ionic bonds to form a complex in the form of an octahedron, and are arranged in a three-dimensionally connected structure.

In addition, cesium ion-exchanged zeolites react with titanium chloride in single crystal or powder form.

The present invention to solve the above another object,

Cesium introduced into the zeolite skeleton; And

Ti ⁴⁺ and Cl ^- is a titanium chloride complex in the form of an octahedron produced by ionic bonding; includes,

The cesium and titanium chloride complex introduced into the zeolite skeleton is ion-bonded by a vapor phase ion exchange method (VPIE) at room temperature, and is prepared with a zeolite scintillator showing a form disposed in the center of the space formed by the zeolite skeleton. It provides an environmental radioactive material measuring device characterized in that.

The present invention provides a zeolite scintillator containing titanium chloride and a manufacturing method thereof, thereby introducing titanium, which was difficult to be introduced into the zeolite as a conventional liquid ion exchange method through an adsorption method using a gas phase reaction, thereby increasing the economic efficiency of the zeolite scintillator, It reduces the manufacturing process steps, and has an effect of showing excellent glare and luminous yield.

1 shows a compositional map of a zeolite scintillator crystal prepared according to an embodiment of the present invention.
2 is a graph showing the results of measuring the XIL emission spectrum of a zeolite scintillator prepared according to an embodiment of the present invention.
Figure 3 is a graph showing the optical attenuation time of the zeolite scintillator powder prepared according to an embodiment of the present invention.
4 is a stereo view of a representative large cavity of a zeolite scintillator prepared according to an embodiment of the present invention.
5 shows a stereo view of a sodalite cavity of a zeolite scintillator prepared according to an embodiment of the present invention.
Figure 6a shows the structure of TiCl ^6- of the zeolite scintillator prepared according to an embodiment of the present invention.
FIG. 6B shows a form in which each TiCl ^6- ion of a zeolite scintillator prepared according to an embodiment of the present invention is surrounded by 8 Cs ⁺ ions.
FIG. 6c shows a form in which each Cs ₈ TiCl ₆ ⁶⁺ ion of a zeolite scintillator prepared according to an embodiment of the present invention is surrounded by 6 Cs ions.
Figure 6d shows a portion of the Cs ₁₁ TiCl ₆ ⁹⁺ continuum of the zeolite scintillator prepared according to an embodiment of the present invention.

Hereinafter, the present invention will be described in more detail.

In the present specification, when a part “includes” a certain component, it means that the component may further include other components, not to exclude other components, unless otherwise stated.

According to one aspect of the present invention, there is provided a zeolite scintillator represented by Formula 1 below:

[Equation 1]

D _x Cs _y E _z -zeolite

The D is titanium (Ti), E is one or more selected from the group consisting of fluorine (Fluorine, F), chlorine (Choloride, Cl), bromine (Bromine, Br), and iodine (Iodine, I) , x, y, and z mean the number of ions contained in the unit cell which is the most basic repeating unit constituting the zeolite, x is 0.02 to 0.15, y is 4.00 to 8.00, and z is 0.01 to 0.09. Preferably, x is 0.04 to 0.12, y is 5.00 to 7.00, z is 0.03 to 0.07, more preferably x is 0.052 to 0.112, y is 5.61 to 6.21, and z is 0.34 to 0.64.

D is titanium (Ti), E may be chlorine (Choloride, Cl), and titanium and chlorine are connected by ionic bonds to form a complex in the form of an octahedron, and may be arranged in a three-dimensionally connected structure. . In detail, the Ti ⁴⁺ ion occupies a large cavity of 8%, and each Ti ⁴⁺ ion is able to bind in octahedron with six Cl ⁻ ions present in the surroundings.

In the zeolite scintillator, cesium is introduced as an extraframewok ion to the framework of the zeolite, and cesium and chlorine can be connected by forming ionic bonds.

In the present invention, the'zeolite skeleton' may be a skeleton possessed by a zeolite or a skeleton possessed by a synthetic zeolite. For example, the zeolite of the present invention may be a zeolite-A having a skeleton code name of a skeleton structure code name LTA (Linde Type A). Zeolite-A can be expressed as zeolite-LTA based on its framework structure. Zeolite-LTA is one of the zeolites with very small pore entrance.

In addition, in the present invention, elements (ions) not included in the existing zeolite skeleton, such as ion-exchanged elements (ions), may be referred to as'non-skeletal elements (ions)', and elements (ions) constituting the zeolite skeleton are ' Skeletal element (ion)'.

In zeolite, the central atoms, silicon and aluminum atoms, coordinate four oxygen atoms and a tetrahedron, and this unit is called TO ₄ . TO ₄ can form a variety of structures by bonding while sharing oxygen atoms with other central atoms. In this way, a portion made of Si, Al, and O is called a skeleton, and the remaining portion is called a non-skeletal body.

In the unprocessed zeolite, pores existing inside the skeleton are filled with water molecules, but because they are structurally loosely bonded, moisture is easily released when heat is applied, and the skeleton remains intact and the pore interior is easily emptied to other elements into the zeolite skeleton. And particulate matter.

The physicochemical properties of the zeolite depend greatly on the aluminum content of the skeleton, i.e. the Si/Al molar ratio. In addition, depending on the amount of Al ³⁺ contained in the zeolite skeleton, the skeleton becomes negatively charged, and cations exist as non-skeletal species for their charge balance. These cations can be easily replaced with other cations, so zeolites have cation exchange capacity. Zeolite physicochemical properties can be changed by the exchange of these cations.

The titanium chloride complex TiCl ₆ ⁹⁺ formed by the combination of titanium and chlorine forms an ionic bond with 8-ring cesium (Cs ⁺ ) ions in the zeolite skeleton, and more specifically, forms an ionic bond with the chloride of the titanium chloride complex Can be connected. Accordingly, in the large cavity of the zeolite, the 8-ring cesium (Cs ⁺ ) ion can be stabilized by connecting between TiCl ₆ ⁹⁺ ions of adjacent unit cells, and Cs ₁₁ TiCl ₆ ^{9 near} the surface of the crystal ⁺ Can form a continuum.

In addition, titanium and chlorine can be placed in the center of the space formed by the skeleton of the cesium ion-exchanged zeolite. In the zeolite scintillator of the present invention, the titanium chloride complex formed by combining titanium and chlorine is disposed in a large cavity formed by the zeolite skeleton, and the chloride of the titanium chloride complex and cesium in the zeolite skeleton interact to form ionic bonds. Formation to form a titanium-chloride-cesium continuum (Cs ₁₁ TiCl ₆ ⁹⁺ ). At this time, the titanium chloride complex formed by the combination of titanium and chlorine may be located in the center of a large cavity (large cavity) formed by the zeolite skeleton.

The space formed by the zeolite skeleton means a three-dimensional space in the pore dimension that occurs when the zeolite skeleton is arranged in three dimensions. The space formed by the zeolite skeleton may have the same meaning as a cavity, and the pupil may be a sodalite cavity or a large cavity.

Zeolite scintillators can convert high-energy photons into low-energy photons, or visible light, that can be more easily detected. The zeolite scintillator of the present invention exhibits an emission spectrum between 360 nm and 700 nm upon irradiation, and can exhibit maximum emission at a wavelength of 450 to 495 nm, preferably 455 nm to 490 nm maximum emission, , More preferably, it can exhibit the maximum emission at a wavelength of 460 or 485 nm, so it can perform a scintillation role.

According to another aspect of the invention, the step of preparing a cesium ion-exchanged zeolite; And forming a zeolite scintillator by reacting the cesium ion-exchanged zeolite with titanium chloride vapor at room temperature through a vapor phase ion exchange method (VPIE), wherein in the reacting step, the titanium chloride is Provided is a method of manufacturing a zeolite scintillator, which is ion-bonded with cesium of the cesium ion-exchanged zeolite, and is disposed in the center of a space formed through the skeleton of the cesium ion-exchanged zeolite.

It is not possible to introduce titanium ions into zeolites as non-skeletal species using liquid phase ion exchange (LPIE). Titanium has a high charge and a small ionic radius, so it is strongly hydrolyzed in aqueous solutions, and hydrolysis of titanium generates a high concentration of hydrogen ions that are interchangeable with zeolite's own non-skeletal ions, so the zeolite's extraframework site Titanium ions cannot be introduced. In addition, since the acidic solution having a high content of hydrogen ions decomposes the zeolite skeleton, therefore, the introduction of non-skeletal titanium ions into the zeolite is impossible by the liquid phase ion exchange method and vapor phase ion exchange (VPIE) or sorption ( sorption).

In the method of manufacturing the zeolite scintillator of the present invention, there is no additional heating step, and compared to the conventional gas phase ion exchange method including a heating process by ion bonding with cesium of zeolite through a gas phase ion exchange method using titanium chloride vapor at room temperature. It can save manufacturing cost and time, and mass production can be easy.

In addition, in the zeolite scintillator prepared in this way, the titanium chloride complex formed by the combination of titanium and chlorine is placed in a large cavity formed by the zeolite skeleton, and the chloride of the titanium chloride complex and cesium in the zeolite skeleton interact to make ionic bonds. Formation to form a titanium-chloride-cesium continuum (Cs ₁₁ TiCl ₆ ⁹⁺ ). At this time, the titanium chloride complex formed by the combination of titanium and chlorine may be located in the center of a large cavity (large cavity) formed by the zeolite skeleton.

The space formed by the zeolite skeleton means a three-dimensional space in the pore dimension that occurs when the zeolite skeleton is arranged in three dimensions. The space formed by the zeolite skeleton may have the same meaning as a cavity, and the pupil may be a sodalite cavity or a large cavity.

The step of preparing a cesium ion-exchanged zeolite may be performed through a liquid phase ion exchange method (LPIE).

The zeolite containing alkali metal may be reacted with a solution containing cesium ions to exchange the alkali metal with cesium ions in liquid phase, and complete dehydration to form a zeolite containing cesium. In the present invention, the alkali metal of the zeolite skeleton may be partially or completely exchanged with the cesium, and the alkali metal may be sodium.

In the process of manufacturing a zeolite scintillator, titanium chloride is Ti ⁴⁺ and Cl ⁻ are connected by ionic bonds to form a complex in the form of an octahedron, and may be arranged in a three-dimensionally connected structure. In detail, Ti ⁴⁺ ions occupy a large cavity of 8%, and each Ti ⁴⁺ ion can be formed in an octahedron with six Cl ⁻ ions present around it.

In addition, the cesium ion-exchanged zeolite can react with titanium chloride in a single crystal or powder form in which the crystal direction is constant even if the appearance is not surrounded by an intrinsic crystal plane.

According to another aspect of the invention, cesium is introduced into the zeolite skeleton; And Ti ⁴⁺ and Cl ^- is a titanium chloride complex in the form of an octahedron produced by ionic bonding; including, cesium and titanium chloride complex introduced into the zeolite skeleton at room temperature vapor phase ion exchange method (Vapor Phase Ion Exchange , VPIE) to provide an environmental radioactive material measuring device characterized in that it is made of a zeolite scintillator, which is ion-bonded to the center of the space formed by the zeolite skeleton.

Zeolite scintillators can be applied and used in various fields related to radiation safety. For example, in relation to nuclear power generation, a new method for radioactivity safety can be proposed by continuously monitoring at regular intervals after a large amount of self-luminous zeolite sorption sensors are applied to the exhaust ports of the power plant, the surrounding soil, and the surrounding sea.

As a luminescent material, it was designed to coexist functional nano-compounds with radioactive isotopes and optical properties in the zeolite micro-pores for the first time in the world by utilizing the advantages of the zeolite, a porous material, and confirmed the possibility of self-luminescence. Self-luminescence will be possible through liver and interaction.

Hereinafter, examples will be described in detail to specifically describe the present specification. However, the embodiments according to the present specification may be modified in various other forms, and the scope of the present specification is not construed as being limited to the embodiments described below. The embodiments of the present specification are provided to more fully describe the present specification to those skilled in the art.

<Example>

Example 1. Preparation of cesium ion exchanged zeolite

In this example, zeolite Na-A, a colorless, transparent single crystal form synthesized by the J.Charnell method in the laboratory of GT Kokotailo, was used. After placing Na-A crystals in the Pyrex capillary, 5 mL of 0.1M CsC ₂ H ₃ O ₂ (Sigma Aldrich, 99.99%+) (pH=6.2) at 294 K (room temperature) for 24 hours was used to make Na-A single crystals. A cesium ion-exchanged zeolite (|Cs ₇ Na ₅ |[Si ₁₂ Al ₁₂ O ₄₈ ]-A) was prepared by rapidly flowing through a containing capillary tube.

For ease of description in the specification, a cesium ion exchanged zeolite (|Cs ₇ Na ₅ |[Si ₁₂ Al ₁₂ O ₄₈ ]-A) is called Cs,Na-A.

Example 2. Preparation of zeolite scintillator with titanium chloride adsorbed

An anhydrous TiCl ₄ Pyrex tube was attached as a valve to a capillary containing Cs,Na-A prepared according to Example 1, and the capillary and Cs,Na-A were dehydrated under vacuum. After that, the valve was opened to react with TiCl ₄ vapor (1.09 x 10 ³ Pa) for 96 hours at 294 K with Cs,Na-A, and Cs,Na at 294 K for 5 hours to remove unreacted TiCl ₄ . -A was emptied. Through the above process, the capillary containing the product containing Ti, Cl, Cs, and Na-A was sealed with a torch in a vacuum.

The zeolite scintillator prepared by the above process is referred to as <Ti,Cl,Cs,Na-A> to facilitate description on the specification.

Example 3. X-ray diffraction measurement of zeolite scintillator

Synchrotron X-ray using Photon Factory ((PF), Tsukuba, Japan) to confirm the structure of the zeolite scintillator <Ti,Cl,Cs,Na-A> prepared according to Examples 1 to 2 above Diffraction intensity was measured. The BL2D-SMDC program was used to collect data by the omega scan method.

Many data sets were obtained by collecting 72 sets of frames for determination with a 5° scan and an exposure time of 1 second per frame, and basic data files were prepared using the HKL2000 (PF) program. Reflections were indexed by the DENZO program's automatic indexing routine, and negligible modifications to crystal collapse were also applied. The space group pm-3m, the standard for zeolite, was determined by the XPREP program.

Example 4. SEM-EDX measurement of zeolite scintillator

Scanning electron microscopy energy-dispersive X-ray for crystal internal analysis of zeolite scintillator <Ti,Cl,Cs,Na-A> prepared according to Examples 1 to 2 , SEM-EDX). <Ti,Cl,Cs,Na-A> was separated from the capillaries to proceed with SEM-EDX analysis, Horiba X-MAX N50 EDX spectrometer in Hitachi SU8820-SR FE (field emission) scanning electron microscope It was determined at 294 K and 9 x 10 ^-4 Pa with a current of 1 μA and a beam energy of 10 keV.

Example 5. Confirmation of compositional map of zeolite scintillator

According to Example 4, after SEM-EDX analysis, <Ti, Cl, Cs, Na-A> crystals are destroyed, and a compositional map of the new surface of the crystal is confirmed using Trumap, a function of EDX software. Did.

Example 6. Confirmation of light emission of zeolite scintillator

The anhydrous <Ti,Cl,Cs,Na-A> powder was confirmed at room temperature (294 K) using a Flame-T-XR1-EX spectrometer (Ocean Optics, 50kV, 30mA) to confirm the XIL spectrum.

The CCD image of the anhydrous single crystal upon synchrotron X-irradiation was confirmed, and a light-emitting attenuation pattern was measured by connecting a container containing <Ti,Cl,Cs,Na-A> powder to the inlet window of a photomultiplier pipe (PMT, H6610). Did. In this case, an X-ray beam (Golden Engineering, XR200, cold cathode tube X-ray tube, 0.026 to 0.040 mSv/pulse, pulse duration 60 ns) was used, and the pulse shape of the PMT output was 1 GHz digital oscilloscope (WaveRunner 610zi). Registered in and calculated the decay time.

<Evaluation and Results>

Results 1. X-ray diffraction analysis of zeolite scintillator

The results of X-ray diffraction analysis of <Ti,Cl,Cs,Na-A>, a zeolite scintillator prepared according to the above example, are shown in Table 1 below.

Crystal (cube) edge length (mm) 0.070 Cs ⁺ ion exchange (temperature (K), time (h), mL) 294, 12, 5 Dehydration of Cs,Na-A (temperature (K), time (h), pressure (Pa)) 673, 48, 1.5 x 10 ^-4 Reaction of Cs,Na-A and TiCl ₄ (temperature (K), time (h), pressure (Pa)) 294, 96, 1.09 x 10 ³ X-ray source PF(BL-5A) ^a Wavelength (Å) 0.7500 Detector ADSC Quantum-315r Distance between crystal and detector (mm) 60 Crystal color golden yellow Data collection temperature (temperature (K)) 294(1) Space group, number pm-3m, 221 Unit cell size, a (Å) 12.228(1) Up to 2θ of data collection (deg) 74.32 Measured reflection 50,300 Specific reflection measured, m 842 Reflection of F _o > 4σ ( F _o ) 764 Variable, s 45 Data/parameter ratio, m / s 18.7 Weight parameters: a, b 0.079, 2.87 Final error indices: R ₁ ^b , R ₂ ^c 0.0460, 0.1429 Goodness of fit ^d 1.10

In the above table, ^a particle accelerator is BL-5A from Japan, ^b R ₁ = Σ|F _o- |F _c ||/ΣF _o ; R ₁ is calculated using the reflection for F _o > 4σ(F _o ). ^c R ₂ = [Σw(F _o ² -F _c ² ) ² /Σw(F _o ² ) ² ] ^1/2 is calculated using all measured specific reflections. ^d Goodness of fit is calculated as (Σw(F _o ² -F _c ² ) ² /(ms)) ^1/2 .

Result 2. SEM-EDX analysis of zeolite scintillator

The results of SEM-EDX analysis of the <Ti,Cl,Cs,Na-A> crystals, which are zeolite scintillators prepared according to the above examples, and the elemental composition thereof are shown in Table 2 below.

element SXRD SEM-EDX Unit cell 1 (8.2%)
(Including TiCl ₆ ) Unit cell 2 (91.8%)
(TiCl ₆ not included) Average Si 16.67 15.71 15.79 12.10 Al 10.00 13.20 12.94 9.13 O 53.33 57.82 57.46 59.38 Ti 1.11 - 0.10 1.63 Cl 6.67 - 0.59 6.44 Cs 12.22 6.61 7.07 7.77 Na - 6.60 6.06 3.54

In Table 2, SXRD is a result obtained by single crystal X-ray diffraction, and when compared with the SEM-EDX results, the element composition ratio of Ti and Cl is almost similar. The SEM-EDX analysis is a surface analysis technique, and it is seen that Ti and Cl are several times higher in the elemental composition by SEM-EDX compared to the average composition, so that Ti, Cl, and unit cells 1 are mainly in the zeolite scintillator surface area. It was confirmed that it exists. Therefore, it was confirmed that the Cs ₁₁ TiCl ₆ ⁹⁺ continuum observed in the <Ti,Cl,Cs,Na-A> crystal exists on the outside and the surface, not inside the zeolite crystal.

This, although <Ti,Cl,Cs,Na-A> includes Cs ₁₁ TiCl ₆ ⁹⁺ continuum. This means that the continuum is practically not present inside the crystal. This reason indicates that blocking of the large pores of the zeolite prevents TiCl ₄ (g) from reaching the center of the zeolite and can form on the surface of the crystal.

Result 3. Check compositional map of zeolite scintillator

The <Ti,Cl,Cs,Na-A> crystal, which is a zeolite scintillator prepared according to the above example, was destroyed, and a compositional map of a new surface of the crystal was confirmed and illustrated in FIG. 1. As a result, it was confirmed that titanium, chloride, cesium, and sodium existed in <Ti,Cl,Cs,Na-A>.

Result 4. Confirmation of the emission spectrum of the zeolite scintillator

The results of measuring the XIL spectrum using the <Ti,Cl,Cs,Na-A> powder, which is a zeolite scintillator prepared according to the above example, are shown in FIG. 2. As a result, the XIL spectrum appeared in a wide band ranging from 360 nm to 700 nm, and showed maximum emission at 460 nm and 485 nm. Further, a bright blue light was emitted. This shows that Ti, Cs, Na and Cl are all present in <Ti,Cl,Cs,Na-A>, and the emission center of <Ti,Cl,Cs,Na-A> is TiCl ₆ ^2- ion.

The zeolite scintillator of the present invention absorbs X-ray photons when irradiated with X-rays, and absorbs electrons in the Cl ^- 3 p orbital (valence band maximum) when absorbing X-ray photons. Ti ⁴⁺ 3 d may cause the orbit to move to t _2g levels (conduction band minimum). This is called ligand-to-metal charge transfer (LMCT). The transfer of electrons causes the halide ion, ie, chloride ion (Cl ⁻ ) of the zeolite of the present invention, to be transformed from Cl ⁻ to Cl ⁰ , and the Cl ⁰ state can polarize the environment. In the valence band Cl ⁰ combines with adjacent Cl ⁻ ions to form a V _k center. That is, the polarization of Cl ion system axis relief ^{(axial relaxation) (Cl 0 +} Cl - → Cl 2 -) to indicate, the two negative ion sharing the hole (anions) state is Cl ₂ ^- a molecule or V _k center Shows. The V _k center captures the electrons of the conduction band (Cl ₂ ^2- ) ^* and forms a molecule or self-trapped exciton (STE). The excited (Cl ₂ ^2- ) ^* or STE emits photons, the V _k center disappears after the emission of V _k e excitons, and the zeolite scintillator can regain its initial properties. That is, the scintillation characteristic of the zeolite scintillator is shown from the interaction of electrons in the conduction band having the V _k center, and this can be expressed as in Reaction Scheme 1 below.

[Scheme 1]

_{^{V k + e - → e 0}} (V k e) → h ν,

Here, e ⁰ is an STE having a V _k e array.

In other words, the zeolite scintillator of the present invention absorbs radiation photons by irradiation, and absorption of radiation photons is high charged metal ions of TiCl ₆ ^2- (Ti ⁴⁺ ) in the ligand (Cl ⁻ ) of the zeolite scintillator. Causes electrons to move (charge transfer), and the zeolite scintillator can emit light when the electrons return to Cl.

<Ti,Cl,Cs,Na-A> The optical decay time of the powder was determined according to the pulse shape information recorded as a two-component exponential function, and the ratio of exponential function was y = A ₁ exp( -t /τ ₁ ) + A ₂ exp( -t /τ ₂ ) + y ₀ Where y and y ₀ Are the emission intensities, A ₁ and A ₂ are constants, t is time, and τ ₁ and τ ₂ represent attenuation times. The resulting XIL reduction curve is shown in FIG. 3. As a result, a faster attenuation time (τ ₁ ) was found to be about 0.0953 ms, and a slow attenuation time was found to be about 1.31 ms.

Result 5. Position and structure characteristics of non-skeletal atoms in the zeolite scintillator crystal

The location and structure characteristics of the non-skeletal atoms of the <Ti,Cl,Cs,Na-A> crystal, which is a zeolite scintillator prepared according to the above example, were confirmed.

Table 3 below shows the positions of non-skeletal elements in the structure determination steps of the zeolite scintillator.

step Number of ions or atoms per unit cell Error indexes Ti Cs1 Cs2 Cs3 Cs4 Na Cl R _One R ₂ One 0.49 0.84 2 2.27(8) 0.32 0.75 3 2.41(5) 1.37(6) 0.17 0.58 4 3.07(4) 1.84(4) 5.50(21) 0.11 0.32 5 2.96(3) 0.75(4) 1.84(3) 5.99(15) 0.083 0.235 6 2.95(3) 0.75(4) 0.49(14) 1.35(14) 5.99(14) 0.075 0.222 7 2.94(3) 0.76(3) 0.51(14) 1.34(14) 5.98(14) 0.068 0.203 8 2.942(16) 0.781(22) 1.18(16) 0.70(16) 5.95(9) 0.0462 0.1381 9 0.038(17) 2.944(16) 0.773(23) 1.21(16) 0.68(16) 5.97(9) 0.0456 0.1394 10 0.12(3) 2.995(18) 0.94(3) 1.52(9) 0.56(9) 5.43(9) 0.52(14) 0.0448 0.1384 11 0.11(3) 2.996(18) 0.94(3) 1.53(9) 0.57(9) 5.43(9) 0.54(14) 0.0446 0.1387 12 0.082(10) 2.993(17) 0.942(24) 1.43(8) 0.66(8) 5.42(9) 0.49(6) 0.0446 0.1389 13 0.082(9) 2.970(17) 0.912(24) 1.37(7) 0.66(7) 5.06(3) 0.49(5) 0.0460 0.1429

Table 4 below shows the location, heat, and occupancy parameters as the final structural parameters of the zeolite scintillator.

The results of stepwise analysis of the structure of <Ti,Cl,Cs,Na-A> crystals in Tables 3 to 4 and the final positions and thermal parameters of each element in <Ti,Cl,Cs,Na-A> I could confirm.

Table 5 below shows some inter-atomic distances and angles in <Ti, Cl, Cs, Na-A>.

Street Angle T-O1 1.6539(14) O1-T-O2 106.60(18) T-O2 1.6527(9) O1-T-O3 112.56(12) T-O3 1.6733(9) O2-T-O3 107.42(11) mean TO ^b 1.663 O3-T-O3 109.95(19) mean OTO ^c 109.42 Cs1-O1 3.388(4) Cs2-O3 3.127(5) T-O1-T 145.9(3) Cs3-O3 2.904(6) T-O2-T 157.27(24) Cs4-O3 3.099(21) T-O3-T 142.56(18) mean TOT ^d 147.1 Na-O3 2.281(3) O1-Cs1-O1 90, 180 ^e Cl-Cs1 3.85(13) O3-Cs2-O3 77.18(14) Cl-C 3.68(3) O3-Cs3-O3 84.38(19) O3-Cs4-O3 78.0(6) Ti-Cl 2.27(12) O3-Na-O3 117.54(7) Ti-Cl-Cs1 180 ^f Cl-Ti-Cl 90, 180 ^g

In Table 5, the length of the mean TO bond is 1.663 Å, Si ⁴⁺ -O (1.61 Å) and Al ³⁺ -O (1.74) observed in fully dehydrated Ca ²⁺ -exchanged LSX and hydrated Na-A. Iv) It was shown that it was close to the coupling length, and it was confirmed that there was almost no distortion geometrically.

In addition, the Ti ⁴⁺ -Cl bond length was 2.27 ,, which was shorter than the sum of the radius of Ti ⁴⁺ and Cl ions, 0.68 + 1.81 = 2.49 Å, which converged when considering the error range.

Table 6 below shows the number of ions per unit cell of the zeolite scintillator.

atom position ion Number of ions per unit cell M-O, Å r, Å CN charge x occ. Ti Ti ⁴⁺ 0.082(10) 6 0.33+ Cs1 Cs ⁺ 2.970(17) 3.388(4) 2.06 6 2.97+ Cs2 Cs ⁺ 0.912(24) 3.127(5) 1.81 3 0.91+ Cs3 Cs ⁺ 1.37(7) 2.904(6) 1.58 3 1.37+ Cs4 Cs ⁺ 0.66(7) 3.099(21) 1.78 6 0.66+ Na Na ⁺ 5.06(3) 2.281(3) 0.96 3 5.06+ Cl Cl ^- 0.49(5) 2 0.49- Σ Ti = 0.082, Σ Cs = 5.91, Σ Na = 5.06, Σ Cl = 0.49 Σ charges = 10.81+

In Table 6, M-O represents the shortest junction length from the oxygen skeleton to the metal element, and the radius of ions (r) was obtained by subtracting 1.32 Å (radius of oxygen ions) from M-O. The number of ions per unit cell of the zeolite scintillator in Table 6 was confirmed to be Ti = 0.082 ± 0.03, Cs = 5.91 ± 0.03, Na = 5.06 ± 0.09, Cl = 0.49 ± 0.15.

The detailed structure of the zeolite scintillator <Ti,Cl,Cs,Na-A> showing the above results is shown in FIGS. 4 to 6D.

A stereo view of a representative large pupil of <Ti,Cl,Cs,Na-A> is shown in FIG. 4. FIG. 4 is a diagram including TiCl ₆ ^2-, and the binding of six Cl-Cs1 is not drawn for clear distinction between ions.

The stereo view of the sodalite pupil of anhydrous <Ti,Cl,Cs,Na-A> is shown in FIG. 5. 5A shows TiCl ₆ ^2- and a sodalite pupil adjacent to a large pupil, and b is a drawing of a sodalite pupil not adjacent to a large pupil.

Complexes and clusters of <Ti,Cl,Cs,Na-A> are shown in FIGS. 6A to 6D. FIG. 6A shows the structure of TiCl ₆ ^2- , and FIG. 6B shows the relationship of each TiCl ₆ ^2- ion surrounded by 8 Cs ⁺ ions (Cs4), and FIG. 6C shows that each Cs ₈ TiCl ₆ ⁶⁺ unit is 6 indicates that it is associated with one Cs ⁺ ion (Cs1), Figure 6d shows a portion of the Cs ₁₁ TiCl ₆ ⁹⁺ continuum that 8TiCl ₆ ^2- ions are formed is connected to the bridge 12 Cs1 ion. In FIG. 6D, Cs4 is omitted for clarity.

According to Figures 4 to 6d, there are 6 Cs ⁺ ions per unit cell, 8-ring Cs1 in the center of <Ti,Cl,Cs,Na-A>, 6-ring Cs2 in the sodalite pupil, It was confirmed that Cs3 and Cs4 were located in the large pupil. The Cs ⁺ ion binds to the oxygen atom of the skeleton, Cs1 is 3.388(4) Å, Cs2 is 3.127(5) Å, Cs3 is 2.904(6) Å, and Cs4 is the distance from the oxygen atom of 3.099(21) Å. Shown.

In addition, only 8.2(10)% of the large pupils had Ti ⁴⁺ ions, and the center was in the center of each of the large pupils far from the negative skeleton. It was confirmed that each Ti ⁴⁺ ion forms six Cl ⁻ ions and an octahedral TiCl ₆ ^2- .

Each TiCl ₆ ^2- ion can be stabilized by 24 Cl ^-- Cs ⁺ ionic bonds between 6 Cl ^- ions and 8 Cs ⁺ (Cs4) ions (Cs4-Cl = 3.68(3) Å), The Cs ₈ TiCl ₆ ⁶⁺ cluster bridge consists of a three-dimensional Cs ₁₁ TiCl ₆ ⁹⁺ continuum with Cl ^- ions of other Cs ₈ TiCl ₆ ⁶⁺ clusters of adjacent unit cells through each 8-ring Cs ⁺ ion (Cs1). It was confirmed that can be configured.

Claims (11)

Zeolite scintillator represented by the following formula (1):
[Equation 1]
D _x Cs _y E _z -zeolite
The D is titanium (Ti), E is one or more selected from the group consisting of fluorine (Fluorine, F), chlorine (Choloride, Cl), bromine (Bromine, Br), and iodine (Iodine, I) ,
x, y, and z means the number of ions contained in the unit cell, which is the most basic repeating unit constituting the zeolite,
Zeolite scintillator, characterized in that x is 0.02 to 0.15, y is 4.00 to 8.00, and z is 0.01 to 0.09. According to claim 1,
The D is titanium (Ti), E is a chlorine (Choloride, Cl) zeolite scintillator, characterized in that. According to claim 2,
The titanium and chlorine are connected by an ionic bond to form a complex in the form of an octahedron, zeolite scintillator, characterized in that arranged in a three-dimensionally connected structure. According to claim 1,
In the zeolite scintillator, cesium is introduced as an extraframewok ion into the framework of the zeolite,
The cesium and chlorine is a zeolite scintillator, characterized in that it is connected by forming an ionic bond. According to claim 3,
The titanium and chlorine is a zeolite scintillator, characterized in that disposed in the center of the space formed by the skeleton of the cesium ion-exchanged zeolite. According to claim 1,
It shows the emission spectrum between 360 nm and 700 nm by radiation,
Zeolite scintillator characterized in that it exhibits the maximum emission at a wavelength of 450 to 495 nm. Preparing a cesium ion exchanged zeolite; And
Including the step of forming a zeolite scintillator by reacting the cesium ion-exchanged zeolite and titanium chloride vapor at room temperature through Vapor Phase Ion Exchange (VPIE).
In the reacting step,
The titanium chloride is ion-bonded with the cesium of the cesium ion-exchanged zeolite, and the method of manufacturing a zeolite scintillator, characterized in that disposed in the center of the space formed through the skeleton of the cesium ion-exchanged zeolite. The method of claim 7,
The method of manufacturing the cesium ion exchanged zeolite is a method of manufacturing a zeolite scintillator characterized in that it is made through a liquid phase ion exchange method (Liquid Phase Ion Exchange, LPIE). The method of claim 7,
The titanium chloride is a method of manufacturing a zeolite scintillator, characterized in that Ti ⁴⁺ and Cl ⁻ are connected by ionic bonds to form a complex in the form of an octahedron, and arranged in a three-dimensionally connected structure. The method of claim 7,
The cesium ion-exchanged zeolite is a zeolite scintillator manufacturing method characterized in that it reacts with titanium chloride in a single crystal or powder form. Cesium introduced into the zeolite skeleton; And
Ti ⁴⁺ and Cl ^- is a titanium chloride complex in the form of an octahedron produced by ionic bonding; includes,
The cesium and titanium chloride complex introduced into the zeolite skeleton is ion-bonded by a vapor phase ion exchange method (VPIE) at room temperature to be prepared with a zeolite scintillator showing a form disposed in the center of the space formed by the zeolite skeleton. Environmental radioactive material measuring device, characterized in that.

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