A zero-dimensional lead-free metal halide perovskite detector material and a preparation method and application thereof
By preparing a zero-dimensional lead-free metal halide perovskite detector material (C5H12N)3Bi2I12, the problems of dark current noise and lead-based detector toxicity in existing X-ray detector materials have been solved, realizing a high-sensitivity and environmentally friendly X-ray imaging detector suitable for industrial applications.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- ANHUI NORMAL UNIV
- Filing Date
- 2026-03-31
- Publication Date
- 2026-07-14
AI Technical Summary
Existing X-ray detector materials such as a-Se have problems such as high dark current noise, low radiation attenuation efficiency, and difficulty in large-scale production. Lead-based perovskite detectors have environmental and biological toxicity issues.
A zero-dimensional lead-free metal halide perovskite detector material (C5H12N)3Bi2I12 was synthesized through specific steps and applied to an X-ray imaging detector. The process involved mixing bismuth halide, 3-dimethylamino-1-propanol, and hydrogen halide solution, followed by slow cooling to crystallize, washing, and drying to prepare a highly sensitive detector material.
It achieves high-sensitivity X-ray detection, with a sensitivity increase of approximately 62 times, reducing potential hazards to the environment and organisms. The preparation method is simple and easy to operate, making it suitable for industrial production.
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Figure CN122380972A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of perovskite material technology, specifically relating to a zero-dimensional lead-free metal halide perovskite detector material, its preparation method, and its application. Background Technology
[0002] Since Röntgen's discovery of X-rays in 1895, they have been widely used in medical imaging, industrial inspection, inland security, and radiotherapy. Flat-panel X-ray imaging detectors are among the most important components in medical imaging, used to convert X-ray photons into electrons (or visible photons) and provide useful information invisible to the naked eye (early cancer lesions, cardiovascular angiography, X-ray photography, dental films, etc.), which can easily improve diagnostic capabilities and benefit public health.
[0003] a-Se-based X-ray detectors have become the dominant commercial detectors in X-ray imaging due to their high resolution and high quantum efficiency. To separate and collect electron-hole pairs generated by X-rays, a large electric field (up to 10 V μm⁻¹) is typically applied to the a-Se layer, generating a significant dark current through the detector even without irradiation. Dark current is a critical parameter in planar imaging because it acts as noise, causing charge buildup on pixel capacitors and reducing the dynamic range and contrast resolution of the image. Controlling and reducing dark current has been identified as one of the most challenging tasks in a-Se detectors. Furthermore, a-Se exhibits low radiative attenuation efficiency in the high-energy range. In contrast, CdTe and Cd... 0.9 Zn 0.1 Te has attracted increasing interest in the development of X-ray and gamma-ray detectors, which feature large atomic numbers, high density, and wide bandgap. However, the fabrication methods for these semiconductors are complex and time-consuming, and a key challenge is the difficulty in producing high-mass, perfectly formed crystals.
[0004] Recently, halide perovskites have attracted widespread attention in X-ray detection due to their tunable band gaps, strong attenuation capabilities, high carrier mobility, and robust fabrication. In recent years, the exploration of various types of lead-based perovskite detectors for diverse applications has garnered increasing interest. These compounds include CH3NH3PbI3, MAPbBr3, CH(NH2)2PbBr3, CsPbBr3, (FAMA)PbI3, and (FACs)PbI3. Despite significant progress in lead-based perovskite detectors, the toxicity of lead is detrimental to both the environment and organisms. Replacing lead with environmentally friendly elements has become an urgent global need. Summary of the Invention
[0005] To address the aforementioned technical problems, this invention provides a zero-dimensional lead-free metal halide perovskite detector material, its preparation method, and its applications. This metal halide eliminates the use of Pb-based compounds in traditional detectors, reducing the potential harm to the environment and organisms. Its sensitivity at 30V is 1236.87 μC. -1 cm -2 Gyair, which has a 20μC higher α-Se detector than conventional medical imaging detectors. -1 cm -2 An increase of approximately 62 times.
[0006] The technical solution adopted in this invention is as follows:
[0007] This invention provides a zero-dimensional lead-free metal halide perovskite detector material, wherein the zero-dimensional lead-free metal halide perovskite detector material is (C5H 12 N)3Bi2I 12 .
[0008] The zero-dimensional lead-free metal halide perovskite detector material has a maximum sensitivity of 1236.87 μCyair at 30V. -1 cm -2 .
[0009] The present invention also provides a method for preparing the zero-dimensional lead-free metal halide perovskite detector material, the method comprising the following steps: mixing bismuth halide, 3-dimethylamino-1-propanol, and hydrogen halide solution, heating to completely dissolve the raw materials, and then slowly cooling at a cooling rate of 0.3~1.0 h / ℃ to allow it to crystallize, and washing and drying the obtained crystals to obtain the zero-dimensional lead-free metal halide perovskite detector material.
[0010] The molar ratio of bismuth halide, 3-dimethylamino-1-propanol, and hydrogen halide is 1:3:30.
[0011] The bismuth halide is bismuth iodide; the hydrogen halide solution is a hydrogen iodide solution with a mass concentration of 35-40%.
[0012] The ratio of bismuth halide to hydrogen halide solution is 0.5 mmol: 3~5 mL.
[0013] The heating conditions are 85~95℃ and maintained for 2~3 hours.
[0014] The crystallization time is 3 to 5 days.
[0015] The washing process involves multiple washes with isopropanol; the drying process involves drying in a vacuum drying oven at 50-70°C for 4-6 hours.
[0016] The present invention also provides the application of the zero-dimensional lead-free metal halide perovskite detector material in X-ray imaging detectors.
[0017] Compared with the prior art, the present invention has the following beneficial effects:
[0018] The zero-dimensional lead-free metal halide perovskite detector material provided by this invention has a novel chemical composition, and its detector performance, including sensitivity, is reported for the first time. This metal halide eliminates the use of Pb-based compounds in traditional detectors, reducing the potential harm to the environment and organisms. Its sensitivity is 1236.87 μC (Gyair). -1 cm -2 (30V), 20μC more than the α-Se detector used in conventional medical imaging. Gyair -1 cm -2 The improvement is approximately 62 times. Furthermore, the preparation method for this zero-dimensional metal halide perovskite detector material is simple, easy to operate, highly efficient, and conducive to industrial production, which further facilitates the application and promotion of this material. Attached Figure Description
[0019] Figure 1 Crystal structure diagram of the zero-dimensional lead-free metal halide perovskite detector material prepared in Example 1;
[0020] Figure 2 The image shows the XRD pattern of the zero-dimensional lead-free metal halide perovskite detector material prepared in Example 1.
[0021] Figure 3 Mapping diagram of the zero-dimensional lead-free metal halide perovskite detector material prepared in Example 1;
[0022] Figure 4 The signal-to-noise ratio-dose rate curve is shown for the zero-dimensional lead-free metal halide perovskite detector material prepared in Example 1.
[0023] Figure 5 The current density-dose rate response curve of the zero-dimensional lead-free metal halide perovskite detector material prepared in Example 1 is shown. Detailed Implementation
[0024] The present invention will now be described in detail with reference to the embodiments.
[0025] Example 1
[0026] A method for preparing a zero-dimensional lead-free metal halide perovskite detector material includes the following steps:
[0027] (1) Weigh 0.5 mmol of BiI3, 1.5 mmol of 3-dimethylamino-1-propanol, and 3 mL of 37 wt% HI solution and add them to the culture bottle. Heat at 90 °C for 3 h to dissolve them completely.
[0028] (2) Transfer the culture bottle to a temperature-controlled oven at 90°C and cool it down at a rate of 0.6°C / h to allow it to crystallize. The crystallization time is 4 days.
[0029] (3) The obtained crystal was washed three times with isopropanol and dried in a vacuum drying oven at 60°C for 6 hours to obtain zero-dimensional lead-free metal halide perovskite detector material (C5H). 12 N)3Bi2I 12 Let it be denoted as B1.
[0030] Detection Example 1
[0031] The crystal B1 obtained in Example 1 was examined using a single-crystal X-ray diffractometer, and its crystal structure was constructed using Diamond, as shown below. Figure 1 As shown, its crystal data is shown in Table 1.
[0032] Table 1 records some key data of crystal B1 prepared in Example 1. Using this data, its crystal system, space group, and lattice shape can be determined.
[0033] Table 1
[0034]
[0035] In the data shown in Table 1, lattice constants a, b, and c represent the unit lattice axis lengths of crystal B1 prepared in Example 1, and α, β, and γ represent the inter-axis angles of the unit lattice. As can be seen from the data in Table 1, in (C5H... 12 N)3Bi2I 12 The crystal contains atoms of H, C, N, Bi, and I, with H, C, and N derived from the organic compound 3-dimethylamino-1-propanol. It belongs to the monoclinic crystal system and the P21 / c group (space group 14 of the International Tables for Crystallography). In (C5H... 12 N)3Bi2I 12 Bi in the crystal has an octahedral structure, and two Bi-I octahedra are coplanar to form a [Bi2I9]3-dimer structure.
[0036] Detection Example 2
[0037] The zero-dimensional metal halide detector material B1 prepared in Example 1 was analyzed using powder X-ray diffraction, and the results were compared with those obtained in Detection Example 1. Figure 2 As shown.
[0038] Depend on Figure 2 As can be seen, the obtained X-ray diffraction data is consistent with the diffraction peak results of the crystal data analyzed in Example 1 in Detection Example 1, and no obvious impurity peaks were observed.
[0039] Detection Example 3
[0040] The zero-dimensional metal halide detector material prepared in Example 1 was analyzed using a scanning electron microscope, and the results are as follows: Figure 3 As shown.
[0041] Depend on Figure 3 As can be seen from the mapping analysis, the structure clearly contains elements such as N, Bi, and I. The mapping results indicate that the hybrid metal halide material has been successfully obtained.
[0042] Detection Example 4
[0043] A commercially available W-target X-ray tube (Magpro TUB00155, Moxtek; maximum operating voltage 70 kV, maximum power 12 W) was used as the X-ray source. The dose rate of this X-ray tube was calibrated using a Radcal Accu-Gold X-ray dosimeter and a 10×6-180 ionization chamber. The IV trace and It curve under X-ray irradiation were also recorded using a 6517B high-precision electrometer (Keithley, USA). The detection limit and sensitivity values were obtained by measuring material B1 prepared in Example 1 and fitting the IV trace and It curve, as shown below. Figure 4 , Figure 5 As shown.
[0044] Depend on Figure 4 The detection limit of material B1 prepared in Example 1 was found to be 614 nGy s at 30V. -1 .
[0045] Depend on Figure 5 The sensitivity values of material B1 prepared in Example 1 at different voltages were obtained, with the maximum sensitivity of 1236.87 μC achieved at 30 V. -1 cm -2 .
[0046] The above detailed description of a zero-dimensional lead-free metal halide perovskite detector material, its preparation method, and its application, with reference to the embodiments, is illustrative rather than limiting. Several embodiments may be listed within the defined scope. Therefore, variations and modifications without departing from the overall concept of the present invention should be within the protection scope of the present invention.
Claims
1. A zero-dimensional lead-free metal halide perovskite detector material, characterized in that, The zero-dimensional lead-free metal halide perovskite detector material is (C5H) 12 N)3Bi2I 12 .
2. The zero-dimensional lead-free metal halide perovskite detector material according to claim 1, characterized in that, The zero-dimensional lead-free metal halide perovskite detector material has a maximum sensitivity of 1236.87 μC at 30 V. (Gyair) -1 cm -2 .
3. The method for preparing the zero-dimensional lead-free metal halide perovskite detector material as described in claim 1 or 2, characterized in that, The preparation method includes the following steps: mixing bismuth halide, 3-dimethylamino-1-propanol, and hydrogen halide solution, heating to completely dissolve the raw materials, and then slowly cooling at a cooling rate of 0.3~1.0 h / ℃ to allow it to crystallize. The resulting crystals are washed and dried to obtain zero-dimensional lead-free metal halide perovskite detector material.
4. The preparation method according to claim 3, characterized in that, The molar ratio of bismuth halide, 3-dimethylamino-1-propanol, and hydrogen halide is 1:3:
30.
5. The preparation method according to claim 3 or 4, characterized in that, The bismuth halide is bismuth iodide; the hydrogen halide solution is a hydrogen iodide solution with a mass concentration of 35-40%.
6. The preparation method according to claim 3 or 4, characterized in that, The ratio of bismuth halide to hydrogen halide solution is 0.5 mmol: 3~5 mL.
7. The preparation method according to claim 3 or 4, characterized in that, The heating conditions are 85~95℃ and maintained for 2~3 hours.
8. The preparation method according to claim 3 or 4, characterized in that, The crystallization time is 3 to 5 days.
9. The preparation method according to claim 3, characterized in that, The washing process involves multiple washes with isopropanol; the drying process involves drying in a vacuum drying oven at 50-70°C for 4-6 hours.
10. The application of the zero-dimensional lead-free metal halide perovskite detector material as described in claim 1 or 2 in X-ray imaging detectors.