KR102285706B1 - Scintillator and Method of manufacturing the same - Google Patents

Abstract

A scintillator having high luminous efficiency and fast response characteristics and a method for manufacturing a scintillator are provided. The scintillator performance is shown by the scintillator composition in which perovskite nanoparticles and organic compounds are combined. A scintillator composition that absorbs short-wavelength X-rays or light to form visible light is manufactured in a film type between two substrates or dispersed in a flexible substrate. In addition, the organic compound constituting the scintillator composition generates electrons by a short wavelength, and the formed electrons are transferred to the perovskite nanoparticles. Secondary electrons/holes are formed by electrons transferred to the perovskite nanoparticles, and the light-emitting operation of the perovskite nanoparticles is performed by electron/hole recombination.

Description

Scintillator and method of manufacturing the same

The present invention relates to a scintillator and a method for manufacturing the same, and more particularly, to a scintillator formed by mixing an inorganic crystalline compound and an organic compound and a method for manufacturing the same.

A scintillator refers to a material that generates light when radiation such as X-rays collide, or refers to a part in which a material that generates light by X-rays is processed into various shapes. That is, the scintillator may be a material itself that generates light, or may be a part in which the material is processed into a predetermined shape.

The types of materials constituting the scintillator are largely divided into inorganic compounds and organic compounds, and are divided into liquid, gas, and solid according to the phase of the material. The scintillator may be composed of an inorganic compound or an organic compound depending on the wavelength of the radiation to be converted and the use of the radiation. In addition, the material constituting the scintillator needs to convert radiation into visible light.

A phosphor is used as a scintillator to convert radiation into visible light. The phosphor used is Gadolinium Oxysulfide (GoS) or Cesium Iodide (CsI). Comparing them, CsI has the advantage of being able to obtain an image at a low radiation dose and providing excellent image quality. In addition, GoS has the advantage of having a lower price than CsI.

Examples of the organic compound used as a scintillator include anthracene, stilbene, or naphthalene. They have a benzene ring structure connected in various ways, have excellent durability, and have the advantage of short decay time. In addition, when the sources of X-rays are not parallel, an anisotropic reaction is exhibited in which the energy resolution is rapidly lowered. In addition, it is not easily processed and has the disadvantage that a large size detector cannot be manufactured.

The described inorganic compound has the advantage of high luminous efficiency, and the organic compound has the advantage of a fast transition rate. Therefore, an organic compound is used as a scintillator in a measurement environment that requires rapid signal processing, and an inorganic compound is used as a scintillator in a measurement environment that requires even a fine image. In particular, the inorganic compound is used more than the organic compound because the linearity in which the incident amount or energy of radiation is proportional to the amount of light emitted is higher than that of the organic compound.

However, even if an inorganic compound is used in a scintillator, higher light efficiency is required to obtain a clearer image. In addition, it is still required that the material constituting the scintillator has a high light quantity, excellent linearity, and a fast transition speed.

A first technical object of the present invention is to provide a scintillator having high optical efficiency and fast response characteristics.

In addition, a second technical object of the present invention is to provide a method of manufacturing a scintillator for achieving the first technical object.

The present invention for achieving the above-described first technical problem, a scintillator film disposed between an upper substrate and a lower substrate; and a sealing material for sealing the scintillator film and bonding the upper substrate and the lower substrate, wherein the scintillator film includes an organic compound chemically bonded to the surface of the perovskite nanoparticles. provides a rater.

In addition, the first technical problem of the present invention, a flexible substrate having elasticity or flexibility; and a scintillator composition dispersed in the flexible substrate, wherein the scintillator composition comprises perovskite nanoparticles and an organic compound chemically bonded to the surface of the perovskite nanoparticles. This is also achieved through the provision of a scintillator.

The present invention for achieving the above-described second technical problem, perovskite nanoparticles forming a perovskite solution evenly dispersed in a solvent; forming a high-efficiency hybrid scintillator composition by adding an organic compound to the perovskite solution; disposing a scintillator composition on a lower substrate and applying pressure through the upper substrate or the lower substrate to form a scintillator film; and shielding a space between the lower substrate on which the scintillator film is formed and the upper substrate with a sealing material.

According to the present invention described above, the scintillator may be manufactured in a liquid or solid film type, and may have elasticity and flexibility. In addition, the scintillator composition constituting the scintillator absorbs X-rays or UV light from the organic compound, and the light emitting operation is performed on the perovskite nanoparticles receiving electrons generated from the organic compound. Perovskite nanoparticles performing light-emitting operation have high light output and short delay time. Accordingly, the manufactured scintillator may acquire a fast response characteristic and a fine image.

1 is a schematic diagram for explaining the preparation of perovskite nanoparticles according to a first embodiment of the present invention.
Figure 2 is a schematic diagram showing the crystal structure of the perovskite nanoparticles prepared by the process of Figure 1 above.
3 is an image showing the perovskite nanoparticles according to Preparation Example 1 of the present invention.
4 is a graph showing the lattice constant of the perovskite nanoparticles according to Preparation Example 1 of the present invention.
5 is a graph showing PL (Photoluminescence) data according to the lattice constant of FIG. 4 of the perovskite nanoparticles according to Preparation Example 1 of the present invention.
6 is a graph showing the band gap according to the type of the perovskite nanoparticles of FIG. 3 according to Preparation Example 1 of the present invention.
7 is a schematic diagram illustrating a scintillator composition according to a second embodiment of the present invention.
8 is a conceptual diagram illustrating electron movement of a scintillator composition according to a second embodiment of the present invention.
9 is a schematic diagram illustrating a film-type scintillator according to a third embodiment of the present invention.
10 is a flowchart illustrating a method of manufacturing the film-type scintillator of FIG. 9 according to a third embodiment of the present invention.
11 is an image illustrating light emission due to a change in organic compound concentration of the scintillator composition according to Preparation Example 2 of the present invention.
12 is a graph showing radioluminescence (RL) characteristics in hard X-rays of the synthesizer K-radiator of Preparation Example 2 according to the present invention.
13 is a graph showing RL characteristics in X-rays of the scintillator of Preparation Example 2 of the present invention.
14 is a schematic diagram illustrating a flexible scintillator according to a third embodiment of the present invention.
15 is an image of the scintillator formed in Preparation Example 3 of the present invention and images of the scintillator when ultraviolet rays are incident.
16 is a graph showing PL characteristics when 365 nm UV light is irradiated to the scintillator film according to Preparation Example 3 of the present invention.
17 is a graph showing PL characteristics when UV light of 254 nm is irradiated to the scintillator film according to Preparation Example 3 of the present invention.

Since the present invention can have various changes and can have various forms, specific embodiments are illustrated in the drawings and described in detail in the text. However, this is not intended to limit the present invention to the specific disclosed form, it should be understood to include all modifications, equivalents and substitutes included in the spirit and scope of the present invention. In describing each figure, like reference numerals have been used for like elements.

Unless defined otherwise, all terms used herein, including technical and scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related art, and should not be interpreted in an ideal or excessively formal meaning unless explicitly defined in the present application. does not

Hereinafter, preferred embodiments of the present invention will be described in more detail with reference to the accompanying drawings.

first embodiment

1 is a schematic diagram for explaining the preparation of perovskite nanoparticles according to a first embodiment of the present invention.

Referring to FIG. 1 , _{Cs-oleate is synthesized by mixing and dispersing Cs 2} CO ₃ and oleic acid (OA) in a solvent. Through this, a first synthetic solution of Cs-oleate is formed.

In addition, a lead halide (PbX ₂ ) is dispersed in a solvent in a separate container, and oleic acid and oleylamine are added and dispersed to form a second synthesis solution.

Then, the first synthesis solution is rapidly injected into the second synthesis solution to form perovskite nanoparticles. The formed perovskite nanoparticles preferably have the formula _{CsPbX 3 .}

Figure 2 is a schematic diagram showing the crystal structure of the perovskite nanoparticles prepared by the process of Figure 1 above.

Referring to FIG. 2 , the halide X is located on all surfaces of the cube, and forms a face centered cubic (FCC) structure with the alkali metal Cs disposed at all vertices of the cube. In addition, the alkali metal Cs forms a body centered cubic (BCC) structure with Pb, which is a central metal. In particular, in the face-centered cubic structure, the halide disposed on the surface of the hexahedron has -3 valence, and is characterized by easy bonding with other cations.

The halide used in FIG. 2 is preferably Cl, Br, or I.

Preparation Example 1: Synthesis of perovskite nanoparticles

1.25 mmol Cs2CO3 (purity 99%), 2.5 ml oleic acid (purity 90%) and 40 ml 1-octadesene (purity 90%) are dispersed in a 3-neck flask at 120° C. under vacuum. After dispersion for 1 hour, it was dispersed for 1 hour at 150° C. in N2 atmosphere. Through this, Cs-oleate is synthesized.

_{Subsequently, 0.189 mmol PbX 2} (0.436 g PbI ₂ , 0.347 g PbBr ₂ , 0.263 g PbCl ₂ ) was dispersed in 5 ml 1-octadesene in a 3-neck flask at 120° C. under vacuum. After 1 hour, in an N ₂ atmosphere, oleic acid and oleylamine (oleylamine, purity 70%) are added and dispersed at a temperature of 140 ℃ to 180 ℃ according to the material of _{each PbX 2 .}

Cs-oleate is rapidly injected into a solution in which oleic acid and oleylamine are well dispersed, and the solution is cooled in ice water.

The finished solution is purified at 8500 rpm and 15 °C using a centrifuge to separate nanoparticles in powder form. The nanoparticles are then dispersed in a non-polar solvent such as n-octane, toluene, or cyclohexane.

3 is an image showing the perovskite nanoparticles according to Preparation Example 1 of the present invention.

Referring to FIG. 3 , perovskite nanoparticles having a chemical formula of _{CsPbX 3 are formed by synthesis.} Perovskite nanoparticles have a diameter of about 10 nm or more, and exhibit an optical behavior different from that of quantum dots, whose emission wavelength is determined by the size of the particle. That is, in the perovskite nanoparticles of the present invention, the emission wavelength is determined according to the intrinsic composition of the material or the type of halide.

In addition, the formed perovskite nanoparticles each form a single crystal. Regardless of the size of nanoparticles formed as single crystals, the emission wavelength is determined according to the type of nanoparticles.

4 is a graph showing the lattice constant of the perovskite nanoparticles according to Preparation Example 1 of the present invention.

5 is a graph showing PL (Photoluminescence) data according to the lattice constant of FIG. 4 of the perovskite nanoparticles according to Preparation Example 1 of the present invention.

4 and 5, it can be seen that the larger the size of the halide element, the larger the lattice constant of the perovskite crystal. In addition, CsPbCl ₃ having the smallest lattice constant exhibits photoluminescence (PL) characteristics of the shortest wavelength, and CsPbI ₃ having the largest lattice constant exhibits PL characteristics of the longest wavelength. This is independent of the PL intensity, that is, CsPbCl ₃ is excited by the incident light to form light of the shortest wavelength, and CsPbI ₃ is excited by the incident light to form light of the longest wavelength.

6 is a graph showing the band gap according to the type of the perovskite nanoparticles of FIG. 3 according to Preparation Example 1 of the present invention.

Referring to FIG. 6 , the characteristic of the same tendency as that of FIG. 5 is shown. That is, since CsPbCl ₃ has the largest bandgap, light having a short wavelength is formed, and CsPbI ₃ having the smallest bandgap has the smallest bandgap, so that light having a long wavelength can be formed.

second embodiment

7 is a schematic diagram illustrating a scintillator composition according to a second embodiment of the present invention.

Referring to FIG. 7 , an organic compound is bonded to the surface of the perovskite nanoparticles prepared in Preparation Example 1. The bond may be a halogen bond, an ionic bond, or a hydrogen bond. For example, the organic compound may be 2,5-diphenyloxazole (PPO). Mainly bonding, the nitrogen atom in the oxazole group of diphenyloxazole may be bonded to the halide atom Cl, Br or I of the perovskite nanoparticles. In addition, diphenyloxazole has a benzene ring, and a hydrogen atom of the benzene ring may form a halogen bond, an ionic bond, or a hydrogen bond with a halide atom on the surface of the perovskite nanoparticles.

Therefore, the formed scintillator composition does not show a simple mixture of perovskite nanoparticles and an organic compound, and exhibits a new optical behavior according to a new material.

The organic compound that can be used may be bound or bonded to the surface of the perovskite nanoparticles, and excited by light having a higher energy than the bandgap of the perovskite nanoparticles, so that the bandgap of the perovskite nanoparticles It is preferred that the composition be capable of forming light having a higher energy.

8 is a conceptual diagram illustrating electron migration of a scintillator composition according to a second embodiment of the present invention.

Referring to FIG. 8 , the left side shows the energy level of a diphenyloxazole single molecule, and the right side shows the band gap of the perovskite nanoparticles.

That is, perovskite nanoparticles in which a plurality of molecules form crystal grains use a bandgap model, and diphenyloxazole, which is bonded to the surface of perovskite nanoparticles in molecular units, uses molecular energy levels. is explained by

Diphenyloxazole bound to the surface of the perovskite absorbs in a very high energy region (X-ray) to form electrons. In addition, diphenyloxazole electrons formed by the incident radiation are easily transferred to the perovskite nanoparticles due to the short molecular length. The electrons transferred to the perovskite nanoparticles contribute to the generation of light with a wavelength corresponding to the bandgap of the perovskite nanoparticles.

In order for electrons to be generated and moved, high energy, that is, energy in a region higher than that of visible light or ultraviolet light is required. That is, diphenyloxazole, an organic compound bonded to the surface of the perovskite nanoparticles, absorbs high-energy light such as X-rays, and electrons formed at this time move to the perovskite nanoparticles and move to the perovskite nanoparticles. Contributes to the luminescence of particles.

third embodiment

9 is a schematic diagram illustrating a film-type scintillator according to a third embodiment of the present invention.

Referring to FIG. 9 , the film-type scintillator includes a lower substrate 110 , an upper substrate 120 , a sealing material 130 , and a scintillator film 140 .

The lower substrate 110 and the upper substrate 120 may accommodate the scintillator film 140 , and any material capable of transmitting light or X-rays may be used. In addition, the lower substrate 110 and the upper substrate 120 may be formed of a rigid material or may be formed of a flexible material. For example, the first substrate or the second substrate may have a glass or quartz material, and may include PI (Polyimide), PC (Polycarbonate), PES (Polyethersulfone), PET (Polyethyleneterephthalate), PEN (Polyethylenenaphthalate), or PAR (Polyarylate). ) may be

A scintillator film 140 is accommodated between the lower substrate 110 and the upper substrate 120 . The scintillator film 140 may include a scintillator composition and a solvent.

The scintillator composition includes perovskite nanoparticles and an organic compound. In particular, the organic compound should be able to form electrons by incident light, and the wavelength of the emitted light should be shorter than the emission wavelength of the perovskite nanoparticles. That is, the organic compound should not re-absorb the light emitted from the nanoparticles in the perovskite. In addition, the organic compound may chemically bond with a halide element or chemically bond with a Cs element in the crystal structure of the perovskite nanoparticles. For example, organic compounds include PPO. When electrons are generated by the light absorbed by the organic compound, the formed electrons move to the perovskite nanoparticles, and light emission is performed in the perovskite nanoparticles.

An unremoved solvent may remain in the scintillator film 140 . The solvent included in the scintillator film 140 may include octane or toluene. The solvent is used to provide fluidity or desired viscosity to the scintillator film 140 . The solvent secures fluidity of the scintillator composition that may be provided in the form of particles for molding during the manufacturing process of the scintillator film 140 to facilitate processing or molding.

In addition, a sealing material 130 is formed between the side surface of the scintillator film 140 and the two substrates 110 and 120 . The sealing material 130 is provided to block the scintillator film 140 from contacting the external environment or the atmosphere, and is used to adhere the substrates 110 and 120 disposed on the upper and lower portions of the scintillator film 140 . used for Accordingly, various materials such as an epoxy resin may be used for the sealing material 140 .

10 is a flowchart illustrating a method of manufacturing the film-type scintillator of FIG. 9 according to a third embodiment of the present invention.

Referring to Figure 10, the perovskite solution is prepared (S100). The perovskite nanoparticles obtained according to Preparation Example 1 are uniformly dispersed in a solvent.

Then, the organic compound is added to the perovskite solution. The organic compound is preferably PPO. The introduced organic compound is bound to the surface of the perovskite nanoparticles in the perovskite solution. For example, when PPO as an organic compound is added and the concentration of PPO in the perovskite solution is increased, the perovskite solution starts to change color and the optical behavior is changed. The discolored state of the perovskite solution is called a scintillator composition solution (S110). However, the scintillator composition solution may be in a state having a predetermined viscosity as a very strong fluidity solution or a kind of sol state.

Subsequently, the scintillator composition solution is disposed on the lower substrate, and the scintillator composition solution is covered through the upper substrate. In addition, a uniform pressure is applied to the upper substrate or the lower substrate so that the scintillator composition solution is compressed in the form of a film on the upper substrate and the lower substrate. Accordingly, a scintillator film is disposed between the upper substrate and the lower substrate ( S120 ).

Finally, the space between the upper substrate and the lower substrate is shielded with a sealing material (S130). In addition, it is preferable that there is no space between the side surface of the sealing material and the scintillator film.

A film-type scintillator is manufactured through the above-described process.

Preparation Example 2: Preparation of film-type scintillator

The perovskite nanoparticles prepared according to Preparation Example 1 are prepared. The prepared perovskite nanoparticles are CsPbBr ₃ . Octane is added as a solvent to the glass bottle, and the perovskite nanoparticles are dispersed in the solution to form a perovskite solution.

PPO is added to a glass bottle in which the perovskite nanoparticles are well dispersed. When the added concentration of PPO is increased, at a certain concentration, PPO is no longer soluble in the solvent, but aggregates with each other and appears as a solid phase.

When octane is used as a solvent, PPO changes color in a solution in which perovskite nanoparticles are dissolved at a concentration of 0.1 g/mL, and aggregation of particle phases appears.

11 is an image showing the discoloration of the perovskite nanoparticle solution according to Preparation Example 2 of the present invention.

Referring to FIG. 11 , the upper images show the amount when the concentration of PPO is increased, and the lower images show the perovskite nanoparticle solution when the PPO of the upper image is added at a specific concentration. did it

In the concentration range of 0.001 g/mL to 0.05 g/mL of PPO, the perovskite nanoparticle solution has a green color. This is due to the fact that the perovskite nanoparticles consist of CsPbBr3 that emits green light. That is, it can be seen that PPO does not form a sufficient amount of chemical bonds with the perovskite nanoparticles, and most of the color formed in the solution is due to the optical properties of the perovskite nanoparticles.

When the concentration of PPO is above 0.1 g/mL, the perovskite nanoparticle solution begins to change color to pale yellow. This means that the injected PPO is chemically bonded to the surface of the perovskite nanoparticles beyond the critical point, and a scintillator composition with changed optical properties is formed. In addition, when the concentration of PPO is 0.1 g/mL or more, a kind of sol state in which pale yellow powders aggregate with each other begins to form. The pale yellow powder may be a scintillator composition that is a synthetic material in which PPO is bonded to the surface of the perovskite nanoparticles.

If the concentration of PPO continues to increase and the concentration of PPO reaches 0.5 g/mL, PPO is completely saturated in the solution, and additional input of PPO becomes meaningless.

In addition, it was confirmed that when tolune was used as a solvent, the optical properties of PPO were changed at a concentration of 0.3 g/mL. That is, it can be seen that the solubility of PPO and chemical bonding with perovskite nanoparticles depend on the type of solvent.

Subsequently, as shown in FIG. 11, the scintillator composition with the changed optical properties is placed between two quartz substrates in a glass bottle, and spread thinly with a doctor blade. Through this, a scintillator composition formed in a plate shape between the quartz substrates is obtained. In addition, the spaced space between the quartz substrates is sealed with a resin or the like. Through this, a scintillator using a composition in which perovskite and PPO are combined is manufactured.

12 is a graph showing RL characteristics in hard X-rays of the synthesizer of Preparation Example 2 according to the present invention.

Referring to FIG. 12 , X-rays are incident on the scintillator with an energy of 6 MV. Each scintillator is a scintillator manufactured using the eight kinds of perovskite nanoparticle solutions shown in FIG. 11 above.

Referring to FIG. 12 , it can be seen that the RL peak appears at approximately 520 nm, and the wavelength at which the RL peak appears regardless of the concentration of PPO has little difference between them. That is, it can be seen that the optical behavior of PPO has no effect on changing the emission wavelength of the scintillator composition.

13 is a graph showing RL characteristics in X-rays of the scintillator of Preparation Example 2 of the present invention.

Referring to FIG. 13 , the X-rays incident on each scintillator are light X-rays with energies of 60 kV and 6 MV.

It can be seen from FIG. 13 that as the concentration of PPO increases, the intensity of RL gradually increases. That is, increasing the concentration of PPO in a state where the concentration of perovskite nanoparticles is constant at 5 mg/mL increases the RL intensity. It is perovskite nanoparticles that perform light emission according to the application of X-rays, but as the amount of PPO chemically bound to the surface of the perovskite nanoparticles increases, more electrons are generated in the PPO, It can be seen that the generated electrons move to the perovskite nanoparticles and contribute to light emission.

14 is a schematic diagram illustrating a flexible scintillator according to a third embodiment of the present invention.

Referring to FIG. 14 , the flexible scintillator includes a flexible substrate 210 and a scintillator composition 220 .

The flexible substrate 210 allows the scintillator to have elasticity and flexibility, and the particulate scintillator composition 220 is dispersed on the flexible substrate 210 . The flexible substrate 210 may be PDMS, and any material that has elasticity or flexibility and is easy to disperse the scintillator composition 220 may be used. However, the flexible substrate 210 needs to pass X-rays, UV or visible light well.

In addition, the scintillator composition 220 includes perovskite nanoparticles and an organic compound. In particular, the organic compound should have a wavelength corresponding to a photoluminescence (PL) peak shorter than a wavelength corresponding to the PL peak of the perovskite nanoparticles. In addition, the organic compound may chemically bond with a halide element or chemically bond with a Cs element in the crystal structure of the perovskite nanoparticles. For example, organic compounds include PPO. When electrons are generated by the light absorbed by the organic compound, the formed electrons move to the perovskite nanoparticles, secondary electrons are generated from the perovskite nanoparticles, and the light-emitting operation of the perovskite nanoparticles is performed. do.

For the fabrication of flexible scintillators, flexible substrate solutions, perovskite nanoparticles and organic compounds are prepared.

First, the perovskite nanoparticles disclosed in Example 1 are dispersed in a solvent to form a perovskite solution. Then, an organic compound is added, and some or all of the organic compound is chemically combined with the perovskite nanoparticles to form a scintillator composition. However, the formed solution containing the scintillator composition is not in the form of a discoloration point as in Preparation Example 2, which is called a scintillator composition solution.

Then, the flexible base solution is mixed with the scintillator composition solution to form a scintillator solution. The scintillator solution is poured into the mold, and the solvent is evaporated through heating or drying. Accordingly, a flexible scintillator having excellent bending characteristics is produced by the flexible substrate.

Preparation 3

As the perovskite nanoparticles formed by Preparation Example 1, CsPbBr ₃ and CsPbCl ₃ are prepared. Then, each perovskite nanoparticles are added and dispersed in a glass bottle using octane as a solvent. In this preparation example, each of the nanoparticles is put into each glass bottle.

PPO is added to a glass bottle in which the perovskite nanoparticles are well dispersed in solution. Then PDMS is added and stirred.

Finally, the solution is poured into a mold and dried in an oven to prepare a scintillator of a flexible (flexible) film type.

15 is an image of the scintillator formed in Preparation Example 3 of the present invention and images of the scintillator when ultraviolet rays are incident.

Referring to FIG. 15 , the _{scintillator film composed of CsPbBr 3} nanoparticles and PDMS exhibits yellow color, and the scintillator film to which PPO is added in Preparation Example 3 also exhibits the same yellow color. In addition, the _{scintillator film composed of CsPbCl 3} nanoparticles and PDMS shows white color _{, and the scintillator film of Preparation Example 3 in which CsPbCl 3} nanoparticles, PPO and PDMS are mixed also shows white color.

The images on the right of FIG. 15 show luminescence when each film is irradiated with UV light having a wavelength of 365 nm. It _{can be seen that the scintillator film in which CsPbBr 3} nanoparticles, PPO, and PDMS are mixed shows blue light compared to the case in which PPO is not mixed.

16 is a graph showing PL characteristics when the scintillator film according to Preparation Example 3 of the present invention is irradiated with UV light having a wavelength of 365 nm.

Referring to FIG. 16 , PPO itself exhibits an emission peak at approximately 380 nm.

In addition, it can be seen that when CsPbCl ₃ perovskite nanoparticles are used alone (blue) in PDMS, the peak intensity is very low and blue light is formed at approximately 420 nm. On the other hand, it can be seen that the scintillator in which PPO was added to _{CsPbCl 3} perovskite nanoparticles in PDMS increased the intensity of the PL peak by about 10 times compared to the case in which _{CsPbCl 3 was alone.} That is, the PL intensity of the perovskite nanoparticles is increased by the input of PPO. In addition, the PL characteristics of PPO are not shown.

In addition, when CsPbBr ₃ perovskite nanoparticles are used alone in PDMS (green), a very low PL peak appears at approximately 520 nm. In addition, when PPO is mixed, the PL peak increases by about a factor of two.

17 is a graph showing PL characteristics when UV light having a wavelength of 254 nm is irradiated to the scintillator film according to Preparation Example 3 of the present invention.

Referring to FIG. 17 , when the scintillator is manufactured in a film type using only PPO, an emission peak is formed at about 390 nm. In addition, since the irradiated UV has a short wavelength of 254 nm, PPO can absorb incident light in a wide range. The formed PL spectrum also has symmetry around the peak.

In addition, when CsPbCl ₃ nanoparticles are added to PDMS alone, a very weak PL peak is shown. This is to the extent that it cannot be used as a light emitting device or a scintillator composition. However, when CsPbCl ₃ and PPO are simultaneously added to PDMS, the PL peak in the blue wavelength band of about 420 nm is shown, and the intensity is increased by more than 10 times. In addition, even in the wavelength band corresponding to PPO, the PL intensity is shown to be low.

In addition, an improved PL peak can be confirmed in the scintillator _{in which CsPbBr 3 and PPO are added to PDMS.}

16 and 17 , it can be inferred that the perovskite nanoparticles and PPO in PDMS form a chemical bond with each other and form a scintillator composition. However, in the PDMS, PPO does not sufficiently chemically bond with the perovskite nanoparticles, and it is estimated that it is distributed alone in the PDMS, albeit in a trace amount. This can be inferred from the fact that CsPbCl ₃ +PPO exhibits a predetermined intensity at the intrinsic PL peak wavelength of PPO in FIG. 17 . That is, it is confirmed that light is absorbed in PPO, and electrons generated by absorption of light do not all move to the perovskite nanoparticles, and some are emitted from PPO itself. However, most electrons migrate to the perovskite and contribute to the intrinsic PL properties of the perovskite.

The above-described scintillator according to the present invention may be manufactured in a film form, and may have elasticity and flexibility. In addition, the scintillator composition constituting the scintillator absorbs X-rays or UV light from the organic compound, and the light emitting operation is performed on the perovskite nanoparticles receiving electrons generated from the organic compound. Perovskite nanoparticles performing light-emitting operation have high light output and short delay time. Therefore, the manufactured scintillator can acquire a fine image with fast response characteristics and high resolution.

110: lower substrate 120: upper substrate
130: sealing material 140: scintillator film
210: flexible substrate 220: scintillator composition

Claims (20)

a scintillator film disposed between the upper substrate and the lower substrate and having a scintillator composition;
and a sealing material sealing the scintillator film and bonding the upper substrate and the lower substrate;
The scintillator composition comprises perovskite nanoparticles and diphenyloxazole chemically bonded to the surface of the perovskite nanoparticles,
The scintillator composition is a scintillator, characterized in that it comprises a powder agglomerated at a concentration higher than the concentration of diphenyloxazole that changes color formed in the solution in which the perovskite nanoparticles are dissolved. According to claim 1, wherein the diphenyloxazole is excited by light having a higher energy than the bandgap of the perovskite nanoparticles, light and electrons having an energy greater than the bandgap of the perovskite nanoparticles A scintillator, characterized in that it is a material capable of forming The method of claim 2, wherein the diphenyloxazole generates electrons by incident X-rays or UV light, and the electrons move to the perovskite nanoparticles and move to the perovskite nanoparticles. One of the electrons generates secondary electrons/holes, and a light-emitting operation is performed by recombination of electron-holes. delete The scintillator of claim 1, wherein the scintillator film further comprises a solvent for securing fluidity. The scintillator according to claim 5, wherein the solvent is n-Octane, Cyclohexane, Chloroform, or Toluene. The scintillator of claim 1, wherein the lower substrate or the upper substrate is made of quartz or glass. The method according to claim 1, wherein the lower substrate or the upper substrate comprises PI (Polyimide), PC (Polycarbonate), PES (Polyethersulfone), PET (Polyethyleneterephthalate), PEN (Polyethylenenaphthalate), or PAR (Polyarylate). Scintillator. The scintillator according to claim 1, wherein the perovskite nanoparticles have a size of 10 nm or more in diameter, and the emission wavelength is determined according to the intrinsic composition of the material or the type of halide atom. Forming a perovskite solution in which the perovskite nanoparticles are evenly dispersed in a solvent;
adding diphenyloxazole to the perovskite solution to form a scintillator composition that is agglomerated into particles while discoloration occurs;
disposing a scintillator composition on a lower substrate and applying pressure through the upper substrate or the lower substrate to form a scintillator film; and
and shielding a space between the lower substrate on which the scintillator film is formed and the upper substrate with a sealing material,
The scintillator composition is a method of manufacturing a film-type scintillator, characterized in that the diphenyloxazole is chemically bonded to the surface of the perovskite nanoparticles. delete The method of claim 10, wherein the perovskite nanoparticles _{have a composition of CsPbX 3} (X is Cl, Br or I). 11. The method of claim 10, wherein the solvent remains in the forming of the scintillator composition. delete a flexible substrate having elasticity or flexibility; and
a scintillator composition dispersed in the flexible substrate;
The scintillator composition is
The diphenyl containing perovskite nanoparticles and diphenyloxazole chemically bonded to the surface of the perovskite nanoparticles, the color formed in a solution in which the perovskite nanoparticles are dissolved, the diphenyl A scintillator comprising a powder agglomerated above the concentration of oxazole. [16] The scintillator according to claim 15, wherein the perovskite nanoparticles have a size greater than 10 nm in diameter and have _{a composition of CsPbX 3} (X is Cl, Br or I). The method according to claim 16, wherein the diphenyloxazole is ionic or hydrogen-bonded with a halide on the surface of the perovskite nanoparticles, or has an ionic bond with a cesium cation of the perovskite nanoparticles. scintillator. delete 16. The scintillator of claim 15, wherein the flexible substrate has PDMS. 16. The scintillator of claim 15, wherein a portion of the diphenyloxazole is not chemically bound to the perovskite nanoparticles and remains on the flexible substrate.

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