Cuprous iodide complex and nanoparticles, scintillator thin film thereof and application thereof

Abstract

The application belongs to the field of X-ray scintillator materials and X-ray imaging, and particularly relates to a cuprous iodide complex and nanoparticles thereof, a scintillator film and application thereof. 10 The cuprous iodide complex Cu8I (bttmpe)2 is obtained by liquid-liquid diffusion method from cuprous iodide and a benzotriazole cationic ligand in acetonitrile / methanol solution. The cuprous iodide nanoparticles are a kind of submicrostructure nanoparticles formed by interaction of cuprous iodide, a benzotriazole cationic ligand and polyvinylpyrrolidone (PVP) in ethanol. The cuprous iodide complex and the nanoparticles thereof are used as a scintillator component to prepare a scintillator film, and the obtained scintillator film has high stability and can clearly image the internal structure of various real objects under X-ray irradiation.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of X-ray scintillator materials and X-ray imaging, and particularly relates to preparation of cuprous iodide complex and nanoparticles, preparation of scintillator thin films thereof and application in X-ray imaging. BACKGROUND

[0002] X-ray scintillators can convert high-energy radiation into low-energy ultraviolet-visible photons, and have attracted extensive attention in the fields of medical imaging, security inspection and high-energy physics in recent years. The blocking efficiency of scintillators to X-rays, the conversion efficiency of visible light, the luminescence lifetime and the light transmission direction directly affect the sensitivity, time and spatial resolution of X-ray imaging. Achieving the common improvement of the light yield, stability, environmental friendliness of the scintillator and the uniformity and flexibility of the scintillator screen is an important challenge in this research field. Therefore, developing new high-performance X-ray imaging scintillators has great scientific and practical value.

[0003] The reported perovskite metal halides, such as CsPbBr3, Rb2CuBr3, CsAgBiBr6 and (TPA)CuI2 (TPA = tetrapropylammonium, C 12 H 28 N + ) have attracted extensive attention due to their simple preparation process, tunable band gap, high atomic number (Z) and excellent optoelectronic properties. However, their poor environmental stability, large self-absorption and element toxicity limit their further development. Typical inorganic scintillators such as CsI:Tl, LuAG:Ce, CdWO4 and YAG:Ce have excellent energy resolution and high light yield, but they need to be prepared at high temperature using expensive instruments, which poses challenges to cost-effectiveness, crystal processability and device integration. Organic scintillators have the advantages of abundant materials, scalability and solution processing, and can be manufactured at room temperature through simple procedures; however, due to their limited effective atomic number, insufficient utilization of excitons and competition of non-radiative relaxation, organic scintillators have relatively low X-ray luminescence intensity.

[0004] Cuprous halide complexes combine the advantages of diversification of electronic properties of coordination metal centers, tunability of cuprous halide nuclear cluster structure and modifiability of organic ligand molecules, and have great potential in developing new high-performance scintillators.

[0005] See Xue Chengwen. Preparation and performance of cuprous iodide nanocluster-based complex [D]. Nanjing University of Posts and Telecommunications [2023-10-11]. The research results of the research group provide a kind of cuprous iodide nanocluster-based complex Cu4I4Py4, although the Cu4I4Py4 after nanometerization still has high luminous intensity, Cu4I4Py4 Nanoparticles can be further processed into thin film materials by doping and coating, but due to the stability of the four-core pure coordination bond complex (Cu4I4Py4) needs to be further improved, such as nanoparticles will react with amino group in solution, resulting in luminescence quenching, thereby limiting its application range.

[0006] And at present, most of the cuprous halide complex scintillators are in the form of large single crystals, which are used after grinding, and the particle size is relatively large. It is difficult to prepare uniform, transparent and particle-free thin films due to poor dispersibility, lack of suitable solvents, low effective density of scintillation materials and other problems. Light scattering will lead to reduced resolution, and the stability of the material needs to be improved. SUMMARY

[0007] The purpose of the present application is to provide a new type of organic-inorganic hybrid cuprous halide complex scintillator material, and a sub-micro cuprous iodide nanoscintillator material obtained by further modification based on the scintillator material, and to prepare a uniform, transparent, high-flexibility and high-resolution scintillator thin film by combining a microelectronic printer. A high spatial resolution and high stability scintillator thin film is achieved, and the prepared scintillator thin film can be used for X-ray imaging in a biological environment.

[0008] The technical solution adopted by the present application is as follows:

[0009] In a first aspect, the present application provides a cuprous iodide complex, specifically an organic-inorganic hybrid cuprous halide complex scintillator material, with a chemical formula of Cu8I 10 (bttmpe)2;The organic component in the organic-inorganic hybrid scintillator is a benzotriazole cation ligand bttmpe, and the inorganic component is cuprous iodide;The optimal emission peak range of the scintillator is 575-590nm;The photon yield of the scintillator is 11801±1220 photons / MeV;

[0010] The chemical structure of the benzotriazole ligand bttmpe is as follows:

[0011]

[0012] The present application also provides a preparation method of the above-mentioned organic-inorganic hybrid cuprous halide complex scintillator material, i.e. cuprous iodide complex Cu8I 10The (bttmpe)2 crystal is obtained by a solution diffusion method of a benzotriazole cationic ligand bttmpe and cuprous iodide; the operation steps of the solution diffusion method comprise the following steps: firstly, cuprous iodide is dissolved in acetonitrile to prepare a cuprous iodide acetonitrile solution with a concentration of 0.025-0.05 mmol / ml at normal temperature; then, a benzotriazole cationic ligand solution with a concentration of 0.025-0.1 mmol / ml dissolved in methanol is slowly added to the cuprous iodide acetonitrile solution to prepare a mixed solution, wherein the molar mass ratio of raw materials of the cuprous iodide and the benzotriazole cationic ligand is 2:1; finally, a layer of diethyl ether is laid on the upper layer of the mixed solution to grow the crystal by liquid-liquid diffusion, and the obtained cuprous iodide complex Cu8I 10 The structure of the (bttmpe)2 crystal is shown in Figure 1

[0013] The present application realizes the regulation of the internal nuclear cluster structure of cuprous iodide by selecting a suitable alkyl chain ligand, and synthesizes a novel Cu8I 10 2- chain cluster base complex, and the novel cuprous iodide complex Cu8I 10 The (bttmpe)2 scintillator material can simultaneously exist ionic bonds and coordination bonds, wherein the coordination bonds are formed by N and Cu, and the ionic bonds are located at the outermost end of the long chain. The cuprous iodide complex Cu8I 10 The (bttmpe)2 crystal structure has better chemical and thermal stability due to the existence of two types of bonds, i.e., ionic bonds and coordination bonds, which enhance the binding strength between molecular clusters, and has high luminescent efficiency due to the high-emissive inorganic cluster core Cu8I 10 2- and good hydrophobicity due to the long alkyl chain in the ligand, can be fully dispersed in water and alcohol, and the crystal molecules combined with cuprous iodide often have high solubility in chloroform, DMF and DMSO, so that the inorganic hybrid cuprous halide complex provided by the present application has excellent solution processability due to the high solubility or easy dispersion in common solvents.

[0014] The cuprous iodide complex Cu8I 10 The (bttmpe)2 crystal is yellow under ultraviolet and X-ray, has an emission wavelength of 500-750 nm, an optimal emission peak range of 575-590 nm, an ultraviolet lifetime of 6.7 μs, a luminescent quantum efficiency of 35.5%, an X-ray light yield of 11801±1220 photons / MeV, and a minimum detection limit of 176.94 nGy / s.

[0015] ​In a second aspect, in order to further improve the resolution of the scintillator material for X-ray imaging, the present application also provides a cuprous iodide complex nanoparticle, in particular a submicroscopic cuprous iodide composite nanoparticle scintillator material, which is a composite nanoparticle formed by the electrostatic attraction and coordination interaction between a benzotriazole cationic ligand bttmpe and cuprous iodide in polyvinylpyrrolidone PVP.

[0016] As a preferred embodiment, the preparation steps of the submicroscopic cuprous iodide composite nanoparticle scintillator material specifically include: dissolving PVP in ethanol to prepare a PVP solution with a concentration of 10-20 mg / ml at room temperature, dissolving cuprous iodide in saturated KI solution to prepare a cuprous iodide solution with a concentration of 0.05-0.25 mmol / ml, dissolving benzotriazole ligand bttmpe in methanol to prepare a ligand solution with a concentration of 0.1-0.25 mmol / ml; adding the cuprous iodide solution to the PVP solution to obtain a light yellow transparent CuI / PVP mixed solution, then immediately adding the ligand solution to the CuI / PVP mixed solution, and after 12-13 hours of reaction, centrifuging the nanoparticles at a speed of 8000-12000 revolutions per minute (rpm) per minute, and washing them with deionized water and ethanol twice, respectively, to obtain the nanoparticles. The nanoparticles are near-spherical uniform nanoparticles with a particle size of 500-800 nm. The PVP micelles play a crucial role in stabilizing the Cu-I unit in this process. After the addition of the bttmpe ligand, the clear solution immediately becomes a light yellow suspension, which initially has a weak orange light under ultraviolet light. After 12 hours of reaction, the orange-yellow particles are obtained by centrifugation and washing, and are stored in an ethanol solution, which has an emission peak range of 570-590 nm under ultraviolet light.

[0017] The cuprous iodide nanoparticles have a Cu8I 10 2- core structure, and have both ionic and coordination bonds of the complex. After the formation of the nanoparticles, they have good stability and water resistance due to the presence of hydrophobic groups, and will not react with amino groups in solution to cause luminescence quenching, unlike the Cu4I4Py4 disclosed in the prior art. Therefore, the printing ink as the scintillator film can better disperse and stably exist in water.

[0018] In a third aspect, the present application provides a scintillator film, which is prepared by grinding the organic-inorganic hybrid cuprous halide complex scintillator material provided in the first aspect or the cuprous iodide complex nanoparticles provided in the second aspect into fine powder, mixing the scintillator ink active material with PVA in water at a mass ratio of (1-4):8.5, fully stirring to fully disperse, preparing a scintillator ink with certain viscosity, then coating the scintillator ink on a substrate material to obtain a scintillator coating, and evaporating and drying at room temperature to obtain the scintillator film.

[0019] It should be noted that although the sub-microscopic nanoparticles have certain viscosity due to the presence of PVP in the preparation process, the particles prepared by centrifugal washing and drying finally have no viscosity, and therefore, a high molecular material, polyvinyl alcohol (PVA), is needed as a supporting material for the scintillator film. As a preferred embodiment, the step of mixing the scintillator ink active material with PVA in water is specifically as follows: first, dissolving PVA in water, stirring and dissolving, and then adding the scintillator ink active material dispersed in water.

[0020] As a preferred embodiment, the sub-microscopic nanoparticles as the scintillator ink active material can be prepared by microelectronic printing and coating on a glass substrate, and the specific step of microelectronic printing and coating on the glass substrate includes: injecting the scintillator ink into a microelectronic printer ink capsule, printing the ink on the glass substrate by the pressure of a pump to obtain a scintillator coating, and scraping off the scintillator coating after natural drying at room temperature to obtain the scintillator film.

[0021] In a fourth aspect, the present application provides an application of the scintillator film in X-ray imaging, which uses the scintillator film as a substrate, places an object above the film, irradiates X-rays to the surface of the film, reflects through a prism, and then captures the whole X-ray image through a camera. The object includes samples such as dried small fish, snail shells and chips, and the internal structure of which can be clearly observed through X-ray imaging. The resolution is also obtained by laying a line pair card on the surface of the film through the X-ray imaging system.

[0022] The present application has the following beneficial effects:

[0023] 1. The cuprous iodide complex scintillator material provided in the first aspect of the present application has a novel Cu8I 10 2- (bttmpe)2 complex structure, has ionic and coordination bonds, and can be prepared by simple solution mixing, which is simple in preparation, high in stability, good in luminescence and has solution processability, thereby being conducive to achieving high scintillation performance. 10 (bttmpe)2 complex structure, has ionic and coordination bonds, and can be prepared by simple solution mixing, which is simple in preparation, high in stability, good in luminescence and has solution processability, thereby being conducive to achieving high scintillation performance.

[0024] 2. The sub-micro cuprous iodide nanoparticles provided by the second aspect of the present application are used as the material of the scintillation film, which overcomes the shortcomings of the traditional cuprous iodide crystal, such as large particle size, uneven dispersion and the like, in the preparation of the film. The cuprous iodide PVP nanoscintillator prepared by the one-pot solution synthesis can realize the free diffusion of the particles during the preparation of the film, and finally, a particle-free, uniform and translucent film is formed, thereby obtaining a high spatial resolution of 16.3 lp mm-1. -1 The obtained high resolution exceeds the reported resolution of most transparent single crystal, polycrystalline film and ceramic scintillators, which can be attributed to the highly dispersed sub-micro structure nanoscintillator particles and the uniform and controllable way of preparing the film.

[0025] 3. The Cu8I 10 (bttmpe)2 complex prepared by the present application has simple and convenient preparation mode, and has high stability and luminescence in the states of crystal, nanoparticle and film. The XEL intensity of the Cu8I

[0026] 4. The scintillator film prepared by the present application has the advantages of adjustable area and thickness, flexibility, stretchability and transparency. In addition, different properties of the scintillator film can be prepared by changing the ratio of PVA to the material. By adjusting the doping concentration of the material and PVA at the ratios of 1:8.5, 2:8.5 and 4:8.5, the best resolution is obtained at the ratio of 2:8.5. At the same time, it is proved that the resolution of the scintillator film is related to the doping amount of the polymer, and a better resolution can be obtained if a suitable doping concentration is selected. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 FIG. 1 is a structural diagram of the Cu8I 10 (bttmpe)2 crystal;

[0028] Figure 2a FIG. 2 is an emission spectrum diagram of the Cu8I 10 (bttmpe)2 crystal under X-ray;

[0029] Figure 2b FIG. 3 is an emission spectrum diagram of the Cu8I 10 (bttmpe)2 crystal under ultraviolet light;

[0030] Figure 2c FIG. 4 is a lifetime decay curve of the Cu8I 10 (bttmpe)2 crystal;

[0031] Figure 2d Cu8I 10 Powder actual detection XRD pattern and simulated XRD pattern of (bttmpe)2crystal;

[0032] Figure 3a Cu8I 10 Photoluminescence of (bttmpe)2crystal;

[0033] Figure 3b Cu8I 10 Detection limit of (bttmpe)2crystal;

[0034] Figure 4 Cu8I 10 Powder XRD (a) and SEM image (b) of (bttmpe)2PVP nanoparticles;

[0035] Figure 5 Cu8I 10 Powder XRD (a) and SEM image (b) of (bttmpe)2PVP nanoparticles;

[0036] Figure 6 Cu8I 10 Radiation stability (a) and humidity stability (b) of (bttmpe)2scintillator;

[0037] Figure 7 Cu8I 10 Picture of (bttmpe)2crystal scintillator film under normal light (a) and X-ray resolution test results (b);

[0038] Figure 8 Cu8I 10 Stretchability (a), flexibility (b), transparency (inset is the picture of the film under UV light on the Nantong University logo) (c), controllable area (d) of (bttmpe)2nanoscintillator film;

[0039] Figure 9 Cu8I 10 Resolution of (bttmpe)2nanoscintillator film under different doping ratios (cuprous iodide nanoparticles and PVA), respectively, 1:8.5 (a), 2:8.5 (b) and 4:8.5 (c);

[0040] Figure 10 Cu8I 10X-ray imaging pictures of (bttmpe)2nanoflare scintillator and its resolution, respectively, small fish (insert picture of small fish under normal daylight) (a), snail shell (insert picture of snail shell under normal daylight) (b), long chip (insert picture of long chip under normal daylight) (c) and resolution (d);

[0041] Figure 11 The MTF curve of the scintillator film was measured by the bevel edge method, and the insert was the bevel edge picture of the film. DETAILED DESCRIPTION

[0042] The preferred examples of the present application are described in detail below with reference to the accompanying drawings, so that the advantages and features of the present application can be more easily understood by those skilled in the art, and the scope of protection of the present application is more clearly defined. However, these examples are exemplary, and they are only used to specifically describe the present application, and should not be understood as limiting the present application.

[0043] Raw reagents were purchased directly from commercial chemical reagents. Except for the synthesis of benzotriazole ligand, which was purified, no further purification was performed. Acetonitrile: National Pharmaceutical Group Chemical Reagent Co., Ltd., analytical pure AR, 500 ml; saturated KI solution was obtained by dissolving potassium iodide in water, with a concentration of 1.44 g / ml. Potassium iodide was sourced from National Pharmaceutical Group Chemical Reagent Co., Ltd.

[0044] Equipment model and manufacturer:

[0045] X-ray tube system: Amptek, Mini-X2 as X-ray tube system, including X-ray tube, power supply, control electronics and USB communication with computer, Amptek is the company name.

[0046] Microelectronic printer: Prtronic Scientific 3 microelectronic printer.

[0047] Example 1

[0048] Example 1 provides a specific preparation of the benzotriazole ligand. The specific preparation process is as follows: 0.025 mol of benzotriazole is added to 100 mL of acetonitrile, after stirring for a while, 0.030 mol of K2CO3 and 0.025 mol of 1-bromo-5-chloropentane are added respectively, and the reaction mixture is stirred at room temperature for 48 hours. After the reaction is completed, the clear solution is obtained by filtration, and the acetonitrile is removed under reduced pressure to obtain the crude product. The crude product is an oily substance, which is purified by column chromatography after extraction to obtain a liquid-like oil Cl-pebt; ①KI (5 g, 0.030 mol) is added to a Cl-pebt (5.6 g, 0.025 mol) acetone solution (100 mL). The mixture is stirred at room temperature for 2 hours, and then filtered; ②acetone in the filtrate is evaporated under reduced pressure, then acetonitrile (100 mL) and trimethylamine (33 wt% ethanol solution 7.1 mL) are added, and the crude product is formed after stirring at 60°C for 48 hours. The reaction mixture is evaporated under reduced pressure, washed with diethyl ether, and dried under vacuum to obtain the final product, the long-chain quaternary ammonium salt bttmpe ligand, i.e. the benzotriazole cationic ligand.

[0049] The chemical synthesis path is shown as follows:

[0050]

[0051] Example 2

[0052] Example 2 provides a specific synthesis process of the organic-inorganic hybrid cuprous halide complex scintillator material Cu8I 10 (bttmpe)2 crystal according to the present application, and the specific synthesis process is as follows: 0.1 mmol of CuI is added to 4 mL of acetonitrile in a vial, and then 0.05 mmol of the long-chain quaternary ammonium salt bttmpe ligand prepared in Example 1 is added to the vial dissolved in 2 mL of methanol. Then 4 mL of diethyl ether solution is added to the upper layer of the vial, and the bottle opening is tightly sealed. After standing for one to two days, orange-yellow crystals are obtained.

[0053] Example 3

[0054] Example 3 also provides a specific synthesis process of the Cu8I 10 (bttmpe)2 crystal, and the difference between Example 3 and Example 2 is only that CuI is dissolved in 2 mL of acetonitrile solution, and the long-chain quaternary ammonium salt bttmpe ligand is dissolved in 0.5 mL of methanol;

[0055] Example 3 and Example 2 can obtain the same results, i.e. the color, shape, size, yield and purity of the prepared crystals are the same, under the condition that the ratio of CuI to the ligand is unchanged.

[0056] Example 4

[0057] Example 4 also provides a specific synthesis procedure of Cu8I 10 (bttmpe)2crystal, the difference between Example 4 and Example 2 is only that CuI is dissolved in 6 mL of acetonitrile solution, and the long-chain quaternary ammonium salt bttmpe ligand is dissolved in 0.5 mL of methanol.

[0058] Example 4 and Example 2 can obtain the same results, i.e. the color, shape, size, yield and purity of the prepared crystals are the same, under the condition of ensuring that the ratio of CuI to ligand is unchanged, using different solution concentrations.

[0059] As shown in Figure 4, the Cu8I Figure 2a (bttmpe)2crystal prepared in Example 2 is shown in Figure 5. 10 The emission spectrum of the Cu8I

[0060] As shown in Figure 6, the Cu8I Figure 2b (bttmpe)2crystal prepared in Example 2 is shown in Figure 7. 10 The emission spectrum of the Cu8I

[0061] As shown in Figure 8, the Cu8I Figure 2c (bttmpe)2crystal prepared in Example 2 is shown in Figure 9. 10 The lifetime decay curve of the Cu8I

[0062] As shown in Figure 10, the Cu8I Figure 2d (bttmpe)2crystal prepared in Example 2 is shown in Figure 11. 10 The powder XRD and its simulation diagram of the Cu8I

[0063] As shown in Figure 12, the Cu8I Figure 3a (bttmpe)2crystal prepared in Example 2 is shown in Figure 13. 10 The light yield of the Cu8I Figure 3b (bttmpe)2crystal prepared in Example 2 is shown in Figure 14. 10 The detection limit of the Cu8I 10X-ray emission spectra of (bttmpe)2were collected and the photoluminescence and detection limit were calculated by integration and formula.

[0064] Example 5

[0065] Example 5 provides a cuprous iodide composite nanoparticle scintillator material, Cu8I 10 A specific synthesis procedure of (bttmpe)2PVP nanoparticles is as follows: 0.2 g of polyvinylpyrrolidone (PVP K88-96) was dissolved in 10 mL of ethanol as a PVP ethanol solution, while 0.1 mmol of Cul was dissolved in 2 mL of saturated KI solution. Then, under magnetic stirring, the Cul / saturated KI solution was added dropwise into the PVP ethanol solution, and immediately after the mixed solution became a light yellow transparent state, 0.05 mmol of the benzotriazole cationic ligand prepared in Example 1 was quickly added into the solution dissolved in 0.5 mL of methanol. Within 2 hours of stirring, the solution was orange yellow in color; and after continued stirring, the solution was finally yellow in color. After the reaction was completed in 12 hours, the nanoparticles were collected by centrifugation at 8000 revolutions per minute (rpm) per minute, and washed with deionized water and methanol twice, respectively. The obtained nanoparticles were then dispersed and stored in methanol.

[0066] As shown in FIG. 5, the Cu8I Figure 4 (bttmpe)2PVP nanoparticles prepared in Example 5. 10 The powder XRD (a) and SEM image (b) of (bttmpe)2PVP nanoparticles.

[0067] Example 6

[0068] Example 6 also provides a cuprous iodide composite nanoparticle scintillator material, Cu8I 10 A specific synthesis procedure of (bttmpe)2PVP nanoparticles is as follows: 0.2 g of polyvinylpyrrolidone (PVP K88-96) was dissolved in 10 mL of ethanol as a PVP ethanol solution, while 0.1 mmol of Cul was dissolved in 2 mL of saturated KI solution. Then, under magnetic stirring, the Cul / saturated KI solution was added dropwise into the PVP ethanol solution, and immediately after the mixed solution became a light yellow transparent state, 0.05 mmol of the benzotriazole cationic ligand prepared in Example 1 was quickly added into the solution dissolved in 0.5 mL of methanol. Within 2 hours of stirring, the solution was orange yellow in color; and after continued stirring, the solution was finally yellow in color. After the reaction was completed in 12 hours, the nanoparticles were collected by centrifugation at 8000 revolutions per minute (rpm) per minute, and washed with deionized water and methanol twice, respectively. The obtained nanoparticles were then dispersed and stored in methanol.

[0069] As shown in FIG. 5, the Cu8I Figure 5Cu8I prepared in Example 6 10 (a) and SEM image (b) of (bttmpe)2PVP nanoparticles.

[0070] Test Example 1

[0071] The sample tested was Cu8I in Example 6 10 (bttmpe)2PVP nanoparticles, Cu8I stored in ethanol in Example 6 was used before testing 10 (bttmpe)2PVP nanoparticles were centrifuged to remove ethanol, and then naturally dried before testing: the XEL intensity of the above scintillator material remained unchanged after continuous irradiation for 1000s under a high-dose X-ray of 4.8Gy, showing high radiation resistance; it still maintained good humidity stability after being stored in a 95% humidity environment for 7 days.

[0072] As shown in Figure 6 Cu8I prepared in Example 6 10 Radiation stability (a) and humidity stability (b) of (bttmpe)2PVP nanoparticles scintillator material.

[0073] Example 7

[0074] This example 7 provides a specific process for preparing a scintillator film from a cuprous iodide crystal, and the specific preparation process includes: 170mg of polyvinyl alcohol (PVA) is added to 2ml of water, and stirring and heating treatment is carried out in a sand bath at 80°C until the PVA is completely dissolved and the solution becomes transparent. Then, 40mg of Cu8I 10 (bttmpe)2crystal is ground into a 100-mesh powder and added to the above PVA aqueous solution, and stirred for 1 hour to fully disperse; then, the fully mixed and uniform solution is dropped into the fixed glass mold, and slowly evaporated at room temperature for 12 hours to obtain Cu8I 10 (bttmpe)2scintillator film. Finally, the scintillator film is gently peeled off from the glass mold with tweezers, and the thickness is measured to be 0.32mm by a micrometer.

[0075] Example 8

[0076] This embodiment 8 provides a specific preparation process of a cuprous iodide scintillator thin film, and the specific preparation process comprises the following steps: 850 mg of polyvinyl alcohol PVA is added into 10 mL of water, and stirring and heating treatment is performed in a sand bath pot at 80 °C until the PVA is completely dissolved and the solution becomes transparent. Then, 200 mg of the cuprous iodide nanoscintillator in embodiment 6 is added into 2 mL of water, and is uniformly dispersed by ultrasonic treatment. The obtained nanomaterial dispersion liquid is added into the 10 mL PVA aqueous solution, and stirring is performed for 1-2 hours to form a viscous dispersion mixture. Then, the viscous mixture is scraped and coated on a glass substrate by a microelectronic printer to form a uniform 4*4 cm thin film, and evaporation is performed at room temperature for 12 hours to form a flexible scintillator thin film. Finally, the scintillator film is gently peeled off from the glass substrate by using a pair of tweezers, and the thickness thereof is measured by using a micrometer to be 0.2 mm.

[0077] As shown in Figure 8 Figure 8 shows the long-chain Cu8I 10 (bttmpe)2nanoscintillator thin film has good stretchability (a), flexibility (b), transparency (the inset is a UV picture of the thin film laid on the school badge of Nantong University) (c) and controllable area (d). It is illustrated that the thin film prepared from the cuprous iodide scintillator with a higher concentration still has good stretchability, flexibility, transparency and controllable preparation area.

[0078] Embodiment 9

[0079] This embodiment 9 also provides a specific preparation process of a cuprous iodide scintillator thin film, and the difference from embodiment 8 is that the mass ratio of the cuprous iodide nanoscintillator material to PVA is 1:8.5, and in this embodiment 9, 170 mg of polyvinyl alcohol PVA is added into 2 mL of water, and 20 mg of the cuprous iodide nanoscintillator is added into 1 mL of water; after the flexible scintillator thin film is gently peeled off from the glass substrate by using a pair of tweezers, the thickness thereof is measured by using a micrometer to be 0.18 mm.

[0080] Embodiment 10

[0081] This embodiment 10 also provides a specific preparation process of a cuprous iodide scintillator thin film, and the difference from embodiment 8 is that the mass ratio of the cuprous iodide nanoscintillator material to PVA is 2:8.5;

[0082] Specifically, in this embodiment 10, 170 mg of polyvinyl alcohol PVA is added into 2 mL of water, and 40 mg of the cuprous iodide nanoscintillator is added into 1 mL of water; after the flexible scintillator thin film is gently peeled off from the glass substrate by using a pair of tweezers, the thickness thereof is measured by using a micrometer to be 0.2 mm.

[0083] Embodiment 11

[0084] Example 11 also provides a specific preparation process for a cuprous iodide scintillator film. The only difference from Example 8 is that the mass ratio of the cuprous iodide nanoscintillator material to PVA is 4:8.5. Specifically, in Example 11, 170 mg of polyvinyl alcohol (PVA) is added to 2 mL of water; 80 mg of cuprous iodide nanoscintillator is added to 1 mL of water; a flexible scintillator film is formed, and after being gently peeled off from the glass substrate with tweezers, its thickness is measured to be 0.22 mm using a micrometer.

[0085] Test Example 2

[0086] X-ray imaging: A self-built X-ray imaging platform was used, employing a Mini-X2 as the X-ray tube system. The system consisted of a Mini-X2 X-ray tube (Amptek Inc.) as the excitation source, a charge-coupled device (CCD) camera (Nikon D850), a multi-fiber spectrometer, and the camera itself. The target material for the Mini-X2 X-ray tube was Au, P. max =4W, V max =50kV, I max =80μA, X-ray source distance 2cm from scintillator film. Specifically, during the test, the X-ray source emission current was 70μA, the voltage was 50kV, and the X-ray source distance was 2cm from the scintillator film.

[0087] like Figure 7 The image shows Cu8I prepared in Example 7. 10 (bttmpe)2 Image of the scintillator thin film under normal light (a) and X-ray resolution test results (b).

[0088] like Figure 9 The image shows the long-chain Cu8I prepared in Examples 9-11. 10 (bttmpe)2 nanometer scintillator films prepared with different doping ratios were compared for X-ray imaging resolution. Among them, image a has a doping ratio of 1:8.5, image b has a doping ratio of 2:8.5, and image c has a doping ratio of 4:8.5. Through comparison, it can be seen that the resolution is the highest with a doping ratio of 2:8.5.

[0089] Using the scintillator film prepared in Example 9 as a substrate, the actual object was placed on top of the film. X-rays irradiated the film surface. The X-rays passing through the dried fish, snail shell, and chip were absorbed by the scintillator film and emitted as visible light. After being reflected by a prism, the visible light was captured by a camera to obtain images of the internal structure information of the dried fish, snail shell, and chip. During resolution testing, the dried fish, snail shell, and chip were replaced with wire pair cards. Images of the internal structure of the dried fish, snail, and chip, as well as images of the standard resolution wire pair cards, are shown below.Figure 10 As shown, Figure 11 The MTF curve of the scintillator film was measured by the edge method. The edge picture of the film is shown in the inset, and the resolution is 16.3 lp / mm.

Claims

1. A scintillator thin film, characterized by, The scintillator thin film is prepared by mixing fine powder of an organic-inorganic hybrid cuprous halide complex scintillator material or cuprous iodide complex nanoparticles as a scintillator ink active material with PVA in water at a mass ratio of (1-4):8.5, fully stirring to fully disperse, preparing a scintillator ink with a certain viscosity, then coating the scintillator ink on a base material to obtain a scintillator coating, and evaporating and drying at room temperature to obtain the scintillator thin film; the organic-inorganic hybrid cuprous halide complex scintillator material is a cuprous iodide complex, and the chemical formula is Cu8I 10 (bttmpe)2; the organic component in the organic-inorganic hybrid cuprous halide complex scintillator material is a benzotriazole cation ligand bttmpe, and the inorganic component is cuprous iodide; the optimal emission peak range of the organic-inorganic hybrid cuprous halide complex scintillator material is 575-590 nm; the photon yield of the organic-inorganic hybrid cuprous halide complex scintillator material is 11801±1220 photons / MeV; and the chemical structural formula of the benzotriazole ligand bttmpe is as shown below: 。 2. The scintillator film of claim 1, wherein The cuprous iodide complex is obtained by a solution diffusion method using a benzotriazole cation ligand bttmpe and cuprous iodide.

3. The scintillator film of claim 2, wherein The operation steps of the solution diffusion method include: firstly, dissolving cuprous iodide in acetonitrile to prepare a cuprous iodide acetonitrile solution with a concentration of 0.025-0.05 mmol / ml at room temperature; then, slowly adding a benzotriazole cation ligand solution with a concentration of 0.025-0.1 mmol / ml dissolved in methanol into the cuprous iodide acetonitrile solution to prepare a mixed solution, wherein the molar mass ratio of the cuprous iodide to the benzotriazole cation ligand is 2:1; and finally, laying a layer of diethyl ether on the upper layer of the mixed solution to grow crystals by liquid-liquid diffusion, thereby obtaining the cuprous iodide complex.

4. The scintillator film of claim 1, wherein The cuprous iodide complex nanoparticles are a kind of submicroscopic cuprous iodide composite nanoparticle scintillator material formed by the electrostatic attraction and coordination interaction of the benzotriazole cation ligand bttmpe and the cuprous iodide. The nanoparticle morphology is a near-spherical uniform nanoparticle, and the particle size is 500-800 nm.

5. The scintillator film of claim 4, wherein The preparation method of the cuprous iodide complex nanoparticles includes the following steps: dissolving PVP in ethanol to prepare a PVP solution with a concentration of 10-20 mg / ml at room temperature, dissolving cuprous iodide in saturated KI solution to prepare a cuprous iodide solution with a concentration of 0.05-0.25 mmol / ml, and dissolving the benzotriazole ligand bttmpe in methanol to prepare a ligand solution with a concentration of 0.1-0.25 mmol / ml; adding the cuprous iodide solution into the PVP solution to obtain a light yellow transparent CuI / PVP mixed solution, then immediately adding the ligand solution into the CuI / PVP mixed solution, centrifuging the nanoparticles at a speed of 8000-12000 rpm per minute after 12-13 hours of reaction, and washing the nanoparticles with deionized water and ethanol respectively twice, thereby obtaining the nanoparticles.

6. A scintillator film as defined in claim 1, wherein The step of mixing the scintillator ink active raw material with PVA in water specifically includes: dissolving PVA in water, stirring and dissolving, and then adding the scintillator ink active raw material dispersed in water.

7. A scintillator film as defined in claim 1, wherein The submicroscopic nanoparticles are used as the scintillator ink active raw material, and a scintillator thin film is prepared by microelectronic printing.

8. A scintillator film as defined in claim 7, characterized in that The step of microelectronic printing on the glass substrate includes: injecting the scintillator ink into a microelectronic printer ink capsule, printing the ink on the glass substrate by the pressure of a pump to obtain a scintillator coating, and scraping off the scintillator thin film after natural drying at room temperature.

9. The scintillator thin film of claim 1 is used for X-ray imaging for non-disease diagnosis and treatment purposes.

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