Use of a trispyridyltriazine zinc bromide complex in the preparation of photovoltaic / radiation detectors

Abstract

The application discloses an application of a tripyridyl triazine zinc bromide complex in preparation of a photoelectric / radiation detector and belongs to the technical field of semiconductor photoelectric materials and devices. The application opens up a new use of a known material, the tripyridyl triazine zinc bromide complex, and realizes regulation of carrier transport performance by using free radicals generated by photoinduced electron transfer (PIET) in the ZnBr2(2-TPT) complex for the first time, breaks through the traditional cognition that the material is only used for optical discoloration, and successfully applies the material to the field of electrical detection. The photoelectric / radiation detector based on the tripyridyl triazine zinc bromide complex has high-performance detection performance: the detector prepared based on the ZnBr2(2-TPT) complex has extremely low dark current (originating from high resistance of the material in a dark state) and significant photocurrent response, realizes high on-off ratio and high sensitivity, and can effectively detect weak ultraviolet light and high-energy X rays.

Description

Technical Field

[0001] This invention belongs to the field of semiconductor optoelectronic materials and devices technology, and in particular relates to the application of a tripyridyltriazine zinc bromide complex in the preparation of photoelectric / radiation detectors. Background Technology

[0002] Photodetectors and X-ray detectors, as core transducers that convert photon energy into electrical signals, are central to modern imaging and sensing technologies. Currently, commercially available devices mainly rely on inorganic semiconductor materials such as silicon (Si), germanium (Ge), and cadmium zinc telluride (CZT). However, these inorganic materials typically require high-temperature melting, high-vacuum physical vapor deposition, or expensive single-crystal growth processes, resulting in high manufacturing costs and energy consumption, making it difficult to meet the demand for low-cost, mass production of high-performance detectors.

[0003] To overcome the aforementioned bottlenecks, organometallic complexes offer a new option for novel semiconductor materials due to their combination of structural tunability and ease of processing. Among them, ZnBr2 (2-TPT), a complex formed from 2,4,6-tris(2-pyridyl)-1,3,5-triazine (2-TPT) and zinc bromide, is a known crystalline material. Literature reports (e.g., Lattice solvent controlled photochromism of tripyridyl-triazine-based zinc bromide complexes Inorg. Chem. Front., 2022, 9, 879) confirm its significant photochromic properties, i.e., reversible color changes under illumination. However, current research is limited to elucidating its crystal structure or developing its photochromic applications in anti-counterfeiting and optical storage fields.

[0004] Although photochromism essentially originates from photoinduced electron transfer (PIET) and free radical generation, this process is inevitably accompanied by drastic changes in carrier concentration and conductivity within the material (i.e., photoconductivity), existing technologies often neglect the development of the material's "electrical properties." To date, there have been no reports on constructing detectors using the electrical switching characteristics accompanying the color change of ZnBr2(2-TPT).

[0005] This invention aims to explore the overlooked photo-to-electric conversion potential of this known compound. By utilizing its unique photoinduced electron transfer mechanism, it provides a photoelectric and radiation detector with a simple preparation process (no need for high-temperature and high-pressure single crystal growth) and high sensitivity and high signal-to-noise ratio, effectively overcoming the problems of high difficulty and high cost in the preparation of traditional inorganic high-performance detectors. Summary of the Invention

[0006] To address the aforementioned problems, this invention provides an application of tripyridyltriazine zinc bromide complex in the fabrication of photoelectric / radiation detectors. The main objective of this invention is to utilize the neglected photoinduced electron transfer (PIET) properties and electrical switching performance of tripyridyltriazine zinc bromide complex to provide a photoelectric / radiation detector with a simple fabrication process (no high-temperature single crystal growth required), low dark current, high signal-to-noise ratio, and stable performance. This solves the technical problems of high fabrication cost, complex processes, and limited X-ray absorption efficiency of traditional inorganic semiconductor detectors.

[0007] To achieve the above-mentioned objectives, the present invention adopts the following technical solution: In a first aspect, the present invention provides a tripyridyltriazine zinc bromide complex, wherein the chemical formula of the tripyridyltriazine zinc bromide complex is ZnBr2(2-TPT); The 2-TPT is 2,4,6-tris(2-pyridyl)-1,3,5-triazine.

[0008] This invention has confirmed through numerous experiments that the tripyridyltriazine zinc bromide complex not only has photochromic properties, but also exhibits a significant photoconductive effect under ultraviolet light or X-ray excitation, demonstrating a sensitive transition from a high-resistivity state to a low-resistivity state.

[0009] The crystallographic characteristics of the tripyridyltriazine zinc bromide complex are described below. The crystal structure of the tripyridyltriazine zinc bromide complex includes a coordination structure formed by a ZnBr2 unit and a 2-TPT ligand; wherein the central Zn cation is coordinated by 3 N atoms and 2 Br atoms on the 2-TPT ligand, and adopts a severely distorted square pyramidal coordination configuration.

[0010] Preferably, the crystal belongs to the triclinic crystal system and has P Spatial group structure.

[0011] Preferably, in the crystal structure, the Zn-Br bond length ranges from 2.38(2) to 2.39(2) Å; and the Br-Zn-Br bond angle is 113.56(6)°.

[0012] Preferably, the crystal structure has unique electronic structure features, with a significant deviation between the central Zn cation and the triazine ring plane, the deviation being 0.3514 Å; this deviation is mainly attributed to the -π interaction between the lone pair bromine atom and the triazine electron.

[0013] Preferably, the crystal structure contains a supramolecular assembly structure that facilitates electron transfer; specifically, two ZnBr2(2-TPT) molecules are interconnected through lone pair electron-π interactions between the Br atom and the centroid of the adjacent 2-TPT ligand triazine ring to form a supramolecular dimer.

[0014] Preferably, the supramolecular dimer is further assembled into a supramolecular chain through intermolecular π-π interactions, and the π-π stacking distance is 3.7520(4) Å.

[0015] Preferably, the cell parameters of the crystal structure are: a = 8.60~8.61 Å, b = 10.72~10.73 Å, c = 11.14~11.15 Å, V = 939.0~939.2 Å. 3 .

[0016] Preferably, the cell parameters of the crystal structure are: a = 8.601~8.602 Å, b = 10.727~10.728 Å, c = 11.143~11.144 Å, V = 939.0~939.2 ų.

[0017] Preferably, the cell parameters of the crystal structure are: a = 8.6016(10) Å, b = 10.7273(16) Å, c = 11.1433(11) Å, V = 939.1(2) ų.

[0018] Preferably, the cell parameters of the crystal structure are: α = 112.148(12)°, β = 97.577(9)°, γ = 92.538(10)°, Z = 2, V = 939.1(2) ų.

[0019] Preferably, the crystal structure has dimensions of 3mm × 1.5mm × 1mm.

[0020] The tripyridyltriazine zinc bromide photochromic material exhibits photochromic properties; under ultraviolet light / X-ray irradiation at a wavelength of 365 nm, the material changes from yellow to green. When in the color-changing state, the material possesses a characteristic electron absorption band in the wavelength region of 450 nm to 800 nm. The material also exhibits reversible thermochromic properties; when in the color-changing state, heating at 100 °C for 10 minutes restores it to its initial yellow color.

[0021] This invention marks the first discovery that tripyridyltriazine zinc bromide complexes exhibit significant photoconductivity under photo / radiation-induced conditions. Utilizing its photoinduced electron transfer mechanism, this material can effectively convert ultraviolet light or X-ray energy into electrical signals, and the discolored ground state can significantly modulate the material's carrier transport characteristics. Detector devices fabricated based on this material offer advantages such as simple fabrication processes (no high-temperature sintering required), low dark current, fast photoresponse speed, and high signal-to-noise ratio, providing a new material option for low-cost, flexible, and large-area photoelectric / radiation detection.

[0022] Secondly, the present invention provides an application of the aforementioned tripyridyltriazine zinc bromide complex in the preparation of photoelectric / radiation detectors.

[0023] Furthermore, the photoelectric / radiation detector is an ultraviolet light detector or an X-ray detector.

[0024] Furthermore, the ultraviolet detector has a detection wavelength range of 200 nm - 400 nm; the X-ray detector is used to detect hard X-rays with energies of 50 keV or higher.

[0025] The photoelectric / radiation detector operates by utilizing the conductivity change generated by photoinduced electron transfer (PET) of the tripyridyltriazine zinc bromide complex under light or radiation excitation. At 298 K, the intrinsic conductivity of the tripyridyltriazine zinc bromide complex in the color-changing saturation state is significantly higher than that in the initial state, and the photocurrent of the device increases linearly with the applied bias voltage.

[0026] This invention is the first to discover that, although tripyridyltriazine zinc bromide complexes are known to have photochromic properties, the photoinduced electron transfer that accompanies the color change process can significantly modulate the band structure and carrier transport characteristics of the material, enabling it to be used as a core semiconductor layer in the fields of high-performance photoelectric detection and radiation detection.

[0027] When the photodetector is an ultraviolet (UV) detector, particularly for ultraviolet light detection in the wavelength range of 200 nm to 400 nm (preferably 365 nm), the detector exhibits significant photoconductivity gain under UV illumination; compared to the dark state, the detector's current (photocurrent) increases by up to 1.32 times (on / off ratio). The IV characteristic curve of the detector shows that the photocurrent increases linearly with the increase of the bias voltage, indicating that a good ohmic contact is formed between the semiconductor active layer and the electrode, which is beneficial to the effective collection of charge carriers. The detector has a fast response speed and good reversibility; in periodic illumination-on / off tests, the photocurrent can rise rapidly and stabilize, and can quickly recover to the initial dark current level after the illumination is removed.

[0028] When the photoelectric / radiation detector is an X-ray detector, it can be used as a direct X-ray detector for detecting high-energy ionizing radiation. Under X-ray irradiation (e.g., 50 keV hard X-rays), this detector exhibits sensitive current response characteristics; its photocurrent density shows a good linear relationship with the X-ray dose rate, proving that the tripyridyltriazine zinc bromide complex can be used for quantitative monitoring of radiation dose. Test results show that the detector has significant current switching characteristics under X-ray irradiation, with an on / off ratio of up to 158, demonstrating excellent radiation detection response capability.

[0029] This invention utilizes the unique optical / radiative conductivity modulation characteristics of ZnBr2(2-TPT) to explore new applications of it in optoelectronic devices and high-energy physics detection, providing a new technical solution for the fabrication of low-cost, high-performance, and radiation-resistant detectors.

[0030] Thirdly, the present invention provides a photoelectric / radiation detector based on a tripyridyltriazine zinc bromide complex, comprising an insulating substrate, a semiconductor active layer, and electrode pairs; the semiconductor active layer is disposed on the insulating substrate; the electrode pairs are constructed on both sides of the semiconductor active layer; the semiconductor active layer is formed by pressing the tripyridyltriazine zinc bromide complex. The spacing between the electrode pairs is determined by the size of the semiconductor active layer.

[0031] Furthermore, the electrode pair is selected from silver electrodes or gold electrodes; the electrode pair forms an ohmic contact with the semiconductor active layer.

[0032] Fourthly, the present invention provides a method for preparing a photoelectric / radiation detector based on a tripyridyltriazine zinc bromide complex, comprising the following steps: pressing the tripyridyltriazine zinc bromide complex into a thin sheet as a semiconductor active layer; placing the semiconductor active layer on a cleaned insulating substrate; coating both sides of the semiconductor active layer with a conductive paste and connecting wires; curing at room temperature; and performing detection to obtain the photoelectric / radiation detector based on the tripyridyltriazine zinc bromide complex.

[0033] Furthermore, the cleaning process of the insulating substrate is as follows: selecting the insulating substrate, and sequentially performing solvent ultrasonic cleaning and oxygen plasma treatment; the solvent ultrasonic cleaning includes a first-stage cleaning using deionized water, acetone and isopropanol in sequence, and a second-stage cleaning using n-hexane, chloroform and isopropanol in sequence; the ultrasonic power of each step is 40%~45%, and the time is 10~20 minutes.

[0034] Further, the conductive paste is conductive silver paste, and the coating thickness is 8 µm-12 µm. Preferably, the coating thickness is 10 µm.

[0035] Furthermore, the pressure for pressing the sheet is 0.05-0.10 MPa.

[0036] Furthermore, the curing time is 20-40 minutes. Preferably, the curing time is 30 minutes.

[0037] Furthermore, the testing includes optical microscopy inspection and electrical short-circuit testing; wherein, optical microscopy inspection is used to confirm that there is no overflow or metal bridging at the electrode edge; the electrical short-circuit test is performed by measuring the resistance of a multimeter, and if the reading is close to the resistance of the wire, it is determined to be a short circuit and needs to be remade.

[0038] The preparation method provided by this invention is simple, does not require a high temperature and high vacuum environment, has good electrode contact, and produces a stable device structure that can effectively avoid short circuits, making it suitable for the rapid preparation and evaluation of high-performance devices.

[0039] Compared with the prior art, the present invention has the following advantages and technical effects: (1) This invention opens up a new application for known materials tripyridyltriazine zinc bromide complexes: This invention is the first to use the free radicals generated by photoinduced electron transfer (PET) in ZnBr2(2-TPT) complexes to achieve the regulation of carrier transport performance, breaking through the traditional understanding that this material is only used for optical color change, and successfully applying it to the field of electrical detection.

[0040] (2) The photoelectric / radiation detector based on tripyridyltriazine zinc bromide complex provided by the present invention has high-performance detection performance: the detector prepared based on ZnBr2(2-TPT) complex has extremely low dark current (due to the high resistance of the material in the dark state) and significant photocurrent response, achieving high on / off ratio and high sensitivity, and can effectively detect weak ultraviolet light and high-energy X-rays.

[0041] (3) The photoelectric / radiation detector based on tripyridyl triazine zinc bromide complex provided by the present invention has a simple and low-cost preparation process: Compared with inorganic semiconductors (such as CZT) that require high-temperature melting and expensive single crystal growth processes, the material of the present invention can be prepared by simple liquid-phase synthesis or low-temperature solution processing. The raw materials are cheap and readily available, and there is no need for high-temperature sintering, which greatly reduces the preparation threshold and energy consumption of high-performance detectors, and provides a new technical route for the mass production of low-cost, high-performance photoelectric / radiation detectors. Attached Figure Description

[0042] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0043] Figure 1 This is a structural diagram of sample 1# prepared in Example 1; Figure 2 The flowchart shows the fabrication process of device 1# in Example 2, along with the dual-probe test circuit and wiring diagram. Figure 3 This is a top view of device 1# prepared in Example 2; Figure 4 This is a side view of device 1# prepared in Example 2; Figure 5The conductivity change spectrum of device #1 before and after color change; Figure 6 The photocurrent response diagram of device #1 before color change (1A); Figure 7 The photocurrent response diagram of device #1 after color change (1B); Figure 8 The photocurrent response time diagram of device #1 before color change (1A); Figure 9 Photocurrent recovery time diagram after device #1 changes color (1B) Figure 10 The spectrum of conductivity change before and after X-ray irradiation of device #1 is shown. Figure 11 The diagram shows the X-ray radiation current response of device #1. Detailed Implementation

[0044] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0045] It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the invention. Furthermore, with respect to numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Every smaller range between any stated value or intermediate value within a stated range, and any other stated value or intermediate value within said range, is also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0046] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.

[0047] Various modifications and variations can be made to the specific embodiments described in this specification without departing from the scope or spirit of the invention, as will be apparent to those skilled in the art. Other embodiments derived from this specification will also be apparent to those skilled in the art. This specification and embodiments are merely exemplary.

[0048] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.

[0049] The room temperature in this invention refers to 25±2 ℃.

[0050] Example 1: Preparation of ZnBr2(2-TPT) Complex Zinc bromide (ZnBr2, 11 mg, 0.05 mmol) and 2,4,6-tris(2-pyridyl)-1,3,5-triazine (2-TPT, 15 mg, 0.05 mmol) were placed in a reaction vessel, and 2 mL of DMF (N,N-dimethylformamide) solvent was added. The resulting mixture was sonicated until the solid was completely dissolved, yielding a clear solution. The clear solution was allowed to stand at room temperature for slow solvent evaporation. After 48 h, colorless flaky crystals precipitated from the solution. The crystals were collected and dried (at 25 °C) to obtain the ZnBr2(2-TPT) complex. The yield was calculated to be 58.8% (based on ZnBr2), and this was designated as sample 1#.

[0051] The structure of sample 1# prepared in Example 1 was characterized: Sample 1# was subjected to X-ray single-crystal diffraction testing on a Rigaku FR-X single-crystal diffractometer (test conditions: Mo target, K α Radiation source ( λ = 0.07107 nm), after testing at 297.26 K, via Olex 2 1.5 Analyze the structure.

[0052] X-ray single-crystal diffraction analysis results show that: The sample 1# prepared in Example 1 has the structural formula ZnBr2(2-TPT), belonging to the triclinic crystal system. P Space group.

[0053] The unit cell parameters are: a = 8.6016(10) Å, b = 10.7273(16) Å, c = 11.1433(11) Å, α =112.148(12)°, β = 97.577(9)°, γ = 92.538(10)°, Z = 2, V = 939.1(2) Å 3 .

[0054] The three-dimensional structure of sample 1# prepared in Example 1 includes a coordination structure formed by ZnBr2 units and 2-TPT ligands; the central Zn cation is coordinated by 3 N atoms and 2 Br atoms on the 2-TPT ligand, adopting a severely distorted pyramidal coordination configuration; the Zn–Br bond length ranges from 2.38(2) to 2.39(2) Å; the Br–Zn–Br bond angle is 113.56(6)°. The crystal structure contains supramolecular assembly structures that facilitate electron transfer, including lone pair electron-π interactions between lone pair bromine atoms and the centroid of the adjacent 2-TPT ligand triazine ring, as well as intermolecular π-π interactions (distance 3.7520(4) Å).

[0055] The single-crystal experimental results of sample 1# prepared in Example 1 are consistent with the results simulated based on single-crystal data, indicating that the material is a pure phase.

[0056] Figure 1 The diagram shows the structure of sample 1# prepared in Example 1.

[0057] Example 2: A method for preparing a photoelectric / radiation detector based on a tripyridyltriazine zinc bromide complex. S1. Substrate Cleaning: Place a 10 mm × 10 mm SiO2 substrate in a polytetrafluoroethylene basket and clean it sequentially with deionized water, acetone, and isopropanol using ultrasonic cleaning (40% power, 10 minutes each). After drying with nitrogen, spread it flat in a sterile petri dish. Then, treat it with a ZEPTO oxygen plasma cleaner. Subsequently, clean it sequentially with n-hexane, chloroform, and isopropanol using ultrasonic cleaning (40% power, 10 minutes each). Before use, remove it from the isopropanol and dry it with nitrogen.

[0058] S2. Preparation of the semiconductor active layer: Sample 1# prepared in Example 1 was pressed into a 2.0 × 2.0 × 0.32 mm sample under a pressure of 0.06 MPa. 3 A rectangular thin sheet; S3. Electrode preparation: The semiconductor active layer prepared in S2 is placed on a clean substrate using conductive silver paste. Silver wires are fixed on both sides. Conductive silver paste of about 10 µm thickness is manually applied to ensure that the silver wires are in full contact with the silver paste without overflow. The paste is cured at room temperature for 30 minutes. S4. Device Inspection: After curing, use an optical microscope to inspect the electrode morphology and use a multimeter to check for short circuits. Eliminate faulty devices and record them as device 1#.

[0059] Figure 2 The flowchart shows the fabrication process of device 1# in Example 2, along with the dual-probe test circuit and wiring diagram. Figure 3 This is a top view of device 1# prepared in Example 2; Figure 4 This is a side view of device 1# prepared in Example 2. Figure 3and Figure 4 The sample also includes a heat sink and an ultraviolet lamp, and the sample (semiconductor) is sample 1# prepared in Example 1.

[0060] Performance Test 1 Conductivity tests were performed on device 1# prepared in Example 2: The electrical performance of device #1 was tested using the two-probe method on a Keithley 4200-SCS semiconductor parameter analyzer. To ensure data reliability and avoid environmental interference, the tests were performed on a vacuum probe stage (vacuum level -0.1 MPa). The initial sample (denoted as 1A) and the sample after in-situ UV irradiation for 3 hours until color saturation (denoted as 1B) were tested separately.

[0061] I -V Characteristic test results show that: I of the samples before and after color change -V The characteristic curves all exhibit a linear and symmetrical relationship, indicating that a good ohmic contact has been formed between the silver paste electrode and the sample.

[0062] Figure 5 The image shows the conductivity change spectrum of device 1# before and after the color change. The conductivity test results show that at a temperature of 298 K (25 ℃), the intrinsic conductivity of the initial 1A sample is 9.96 × 10⁻⁶. -11 S cm -1 When the color change of the sample reaches saturation (sample 1B), its intrinsic conductivity decreases to 2.25 × 10⁻⁶. -10 S cm -1 This result indicates that the electron transfer accompanying the photochromic process alters the carrier concentration or mobility of the material.

[0063] Performance Test 2 The photocurrent response and response recovery time of device 1# prepared in Example 2 were tested: The electrical performance of device 1# prepared in Example 2 was tested using the two-probe method on a Keithley 4200-SCS semiconductor parameter analyzer. Under a bias voltage of 5 V, the change of current over time (It curve) was recorded by periodic irradiation with ultraviolet light at a wavelength of 365 nm (Light On / Off).

[0064] Figure 6 The photocurrent response diagram of device #1 before color change (sample 1A); Figure 7 The photocurrent response diagram of device #1 after color change (sample 1B); the photocurrent response test results are as follows. Figure 6 and 7As shown, both the initial state (sample 1A) and the color-changing state (sample 1B) of device 1# exhibit stable and reversible photocurrent switching responses under periodic illumination. Compared to the initial state (sample 1A), the on / off ratio of the color-changing state (sample 1B) is increased, indicating that the photocurrent gain and photodetector sensitivity are enhanced. This demonstrates that the photoinduced electron transfer process effectively optimizes the photodetector performance of the material.

[0065] Figure 8 Photocurrent response time diagram of device #1 before color change (1A sample); Figure 9 The photocurrent recovery time diagram after the color change of device #1 (sample 1B); the response and recovery time test results are as follows: Figure 8 and 9 As shown: The photoresponse speed of the sample was analyzed according to the definitions of response time (time required to rise to 90% of the saturation current) and recovery time (time required to fall to 0% of the maximum response). The test results show that the crystal material has fast response and recovery characteristics to ultraviolet light and can sensitively track changes in the light signal.

[0066] Performance Test 3 Conductivity tests were performed on device 1# prepared in Example 2: The radiation detection electrical performance of device 1# was tested on an X-ray testing platform. The X-ray testing platform was self-built and equipped with a tungsten target X-ray source (power 5 W), a shielding box, and a semiconductor tester (Keithley 4200-SCS semiconductor parameter analyzer). The tube voltage for X-rays was set to 50 kVp, and the dose rate was adjusted by changing the tube current. An external lead box served as the X-ray protection device.

[0067] The initial sample (referred to as sample 1A) and the sample after in-situ X-ray irradiation for 10 minutes until the color changed to saturation (referred to as sample 1B) were tested separately.

[0068] Figure 10 The graph shows the conductivity change of device #1 before and after X-ray irradiation. -V Characteristic test results show that: I of the samples before and after color change -V The characteristic curves all exhibit a linear and symmetrical relationship, indicating that a good ohmic contact has been formed between the silver paste electrode and the sample.

[0069] Conductivity test results show that the intrinsic conductivity of the initial sample 1A is 2.01 × 10⁻⁶ at 298 K (25 °C). -11 S cm -1 When the color change of the sample reached saturation (sample 1B), its intrinsic conductivity decreased to 44.65 × 10⁻⁶. -9 S cm -1This result indicates that the electron transfer accompanying the photochromic process alters the carrier concentration or mobility of the material.

[0070] Performance Test 4 Conductivity tests were performed on device 1# prepared in Example 2. The radiation detection electrical performance of device 1# was tested on an X-ray testing platform. The X-ray testing platform was self-built and equipped with a tungsten target X-ray source (5 W power), a shielding box, and a semiconductor tester (Keithley 4200-SCS semiconductor parameter analyzer). The tube voltage of the X-ray was set to 50 kVp to generate hard X-rays with an energy of 50 keV. The dose rate was adjusted by changing the tube current, and an external lead box served as the X-ray protection device.

[0071] The sample was tested after being irradiated in situ with X-rays for 10 minutes until the color changed to saturation (referred to as sample 1B).

[0072] Under a 5 V bias, the change of current over time (It curve) was recorded by periodic ultraviolet light irradiation (Light On / Off).

[0073] Figure 11 The image shows the X-ray radiation current response of device #1. The photocurrent response test results are as follows: Figure 11 As shown, the color-changing state of device #1 (sample 1B) exhibits a stable and reversible photocurrent switching response under periodic illumination. The on / off ratio of the color-changing state (sample 1B) is as high as 158, indicating its high radiation detection sensitivity. This demonstrates that the photoinduced electron transfer process effectively optimizes the radiation detection performance of the material. With increasing X-ray dose rate, the device output current shows a good linear increase. Utilizing the absorption capacity of this material for heavy atoms (Zn, Br), direct electrical detection of hard X-rays was achieved.

[0074] The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A tripyridyltriazine zinc bromide complex, characterized in that, The chemical formula of the tripyridyltriazine zinc bromide complex is ZnBr2(2-TPT); The 2-TPT is 2,4,6-tris(2-pyridyl)-1,3,5-triazine.

2. The tripyridyltriazine zinc bromide complex according to claim 1, characterized in that, The tripyridyltriazine zinc bromide complex has a crystalline structure belonging to the triclinic crystal system, space group P. Its unit cell parameters are: a = 8.6016(10) Å, b = 10.7273(16) Å, c = 11.1433(11) Å, α = 112.148(12)°, β = 97.577(9)°, γ = 92.538(10)°, Z = 2, V = 939.1(2) Å. 3 .

3. The tripyridyltriazine zinc bromide complex according to claim 2, characterized in that, The crystal structure comprises a coordination structure formed by ZnBr2 units and 2-TPT ligands; wherein the central Zn cation is coordinated by 3 N atoms and 2 Br atoms on the 2-TPT ligand, adopting a severely distorted square pyramidal coordination configuration; the Zn–Br bond length ranges from 2.38(2) to 2.39(2) Å; and the Br–Zn–Br bond angle is 113.56(6)°.

4. The use of the tripyridyltriazine zinc bromide complex according to any one of claims 1-3 in the preparation of photoelectric / radiation detectors.

5. The application according to claim 4, characterized in that, The photoelectric / radiation detector is an ultraviolet light detector or an X-ray detector.

6. The application according to claim 5, characterized in that, The ultraviolet detector has a detection wavelength range of 200 nm - 400 nm; the X-ray detector is used to detect hard X-rays with energies of 50 keV or higher.

7. A photoelectric / radiation detector based on a tripyridyltriazine zinc bromide complex, characterized in that, It includes an insulating substrate, a semiconductor active layer, and an electrode pair; the semiconductor active layer is disposed on the insulating substrate; the electrode pair is constructed on both sides of the semiconductor active layer; the semiconductor active layer is formed by pressing the tripyridyltriazine zinc bromide complex according to any one of claims 1-3.

8. The photoelectric / radiation detector based on a tripyridyltriazine zinc bromide complex according to claim 7, characterized in that, The electrode pair is selected from silver electrodes or gold electrodes; the electrode pair forms an ohmic contact with the semiconductor active layer.

9. A method for preparing a photoelectric / radiation detector based on a tripyridyltriazine zinc bromide complex, characterized in that, The method includes the following steps: pressing the tripyridyltriazine zinc bromide complex according to any one of claims 1-3 into a thin sheet as a semiconductor active layer; placing the semiconductor active layer on a cleaned insulating substrate, coating both sides of the semiconductor active layer with conductive paste and connecting wires, curing at room temperature, and performing detection to obtain the photoelectric / radiation detector based on the tripyridyltriazine zinc bromide complex.

10. The preparation method according to claim 9, characterized in that, The curing time is 20-40 minutes.

Images