Preparation method of X-ray detector based on super-flexible layered polymer perovskite composite film
The ultra-flexible layered polymer perovskite composite film prepared by spray coating and dual-source co-evaporation method solves the problem of signal instability of flexible electronic devices during mechanical deformation, achieves high sensitivity and stability detection under extreme bending conditions, and is suitable for wearable sensors and soft robots.
Patent Information
- Application Number
- CN202510671181.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-23
- Publication Date
- 2025-09-26
AI Technical Summary
Existing flexible electronic devices have insufficient ability to transmit charge and dissipate mechanical stress when subjected to mechanical deformation and angle changes, resulting in unstable output signals and making it difficult to achieve high flexibility and high-performance X-ray detection.
A mixed solution of polymer and perovskite is deposited on a substrate by spraying, and an ultra-flexible layered polymer perovskite composite film is prepared by dual-source co-evaporation. Combined with the ratio control of polymer and perovskite, a layered structure is formed to release strain and achieve stable photoelectric performance.
The prepared X-ray detector is ultra-flexible and fatigue-resistant, and can maintain high sensitivity and stable detection performance under extreme bending conditions. It is suitable for applications such as wearable sensors and soft robots.
Smart Images
Figure CN120711979A_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the technical field of detectors, and in particular relates to a method for preparing an X-ray detector based on an ultra-flexible layered polymer perovskite composite film. Background Art
[0002] Soft, lightweight, and stable semiconductors are the cornerstones of next-generation flexible electronics and can serve as important platforms for wearable sensors, soft robotics, and implantable devices. Intrinsically flexible organic materials have been recognized as particularly suitable for flexible devices, but their electronic performance is often unsatisfactory due to hopping transport behavior. In contrast, inorganic semiconductors such as gallium arsenide and silicon can achieve long carrier diffusion lengths, but their ionic or covalent nature makes them inherently brittle and prone to fracture when the structure is deformed. Therefore, in most existing materials, there is a fundamental trade-off between mechanical flexibility and electronic properties.
[0003] Perovskites, an emerging class of semiconductor materials, boast high absorption coefficients, long carrier diffusion lengths, tunable band gaps, and defect tolerance. Over the past decade, they have revolutionized optoelectronics research, including solar cells, light-emitting diodes, and radiation detectors. Unlike conventional semiconductors, which must be processed using vapor or vacuum processes, solution-based perovskite fabrication offers a technological route to combine these brittle materials with soft organic materials to achieve moderate flexibility. Depositing perovskite thin films on flexible substrates is the mainstream approach for fabricating flexible perovskite devices. However, these devices still suffer from poor bending tolerance and delamination. In recent years, several chemical and physical approaches, including molecular crosslinking, interface strengthening, perovskite composition engineering, polymer blending, and nanostructure patterning, have been proposed to minimize mechanical fatigue in peritectic films. However, the ability to transport charge and dissipate mechanical stress, prerequisites for flexible electronics applications, to provide stable output signals under mechanical deformation and angular variations, is not easily achieved in typical composite structures. Summary of the Invention
[0004] The purpose of the present invention is to provide a method for preparing an X-ray detector based on an ultra-flexible layered polymer perovskite composite film.
[0005] Another object of the present invention is to provide an X-ray detector based on an ultra-flexible layered polymer perovskite composite film prepared by the method and to use it in the preparation of wearable sensors, soft robots, and implantable devices.
[0006] In order to achieve the above object, the technical solution adopted by the present invention is as follows:
[0007] In a first aspect of the present invention, a method for preparing an X-ray detector based on an ultra-flexible layered polymer perovskite composite film is provided, comprising the following steps:
[0008] Mixing a perovskite storage solution and a polymer storage solution having a solid mass fraction of 5-20% (preferably 15%) to obtain a polymer and perovskite mixed solution having a perovskite mass fraction of 1-90% (preferably 10%, 30%, 40%, 50%, 65%, 80%, 85%, 90%);
[0009] The dried substrate is treated with ultraviolet ozone (10-30 minutes, preferably 15 minutes), and a mixed solution of polymer and perovskite with a perovskite mass fraction of 1-90% (preferably 10%, 30%, 40%, 50%, 65%, 80%, 85%, 90%) is converted into aerosol droplets. The aerosol droplets are deposited on the dried substrate by a spraying method, and the deposition is repeated multiple times (1-1000 times, preferably 15 times). The film is removed from the substrate and a lateral counter electrode is deposited by a dual-source co-evaporation method (performed by a vacuum evaporation coater, requiring a heating current of 100-130A, preferably 120A, and an evaporation time of 20-60min, preferably 30min) to obtain an X-ray detector based on an ultra-flexible layered polymer perovskite composite film.
[0010] The preparation method of the polymer storage solution is as follows:
[0011] DMF is added to the polyimide mother solution and stirred thoroughly (preferably for 6 hours) to obtain a polymer stock solution with a solid mass fraction of 5-20% (preferably 15%).
[0012] The perovskite is selected from CH3NH3PbI3 (MAPbI3), CH3NH3PbBr3 (MAPbBr3), CH(NH2)2PbI3 (FAPbI3), CsPbBr3, Cs x FA y MA 1-x-y PbI z Br 3-z 、Cs x MA 1-x PbI y Br 3-y 、Cs x FA 1-x PbI y Br 3-y , FA x MA 1- x PbI y Br 3-y 、CsPbI x Br 3-x, Cs2AgBiBr6, etc. The x value range of ternary perovskite is 0~1, the y value range is 0~1, and the z value range is 0~3. The x value range of binary perovskite is 0~1, the y value range is 0~3, and the x value range of mono-perovskite is 0~3.
[0013] The polymer is selected from polyimide, polyvinyl pyrrolidone and the like.
[0014] The preparation steps of the dried substrate are as follows: the substrate is repeatedly ultrasonically cleaned at least three times with deionized water, acetone, and ethanol in sequence, and dried to obtain a dried substrate.
[0015] The substrate is selected from glass substrates, silver substrates, copper substrates and other substrates of any material and shape.
[0016] The polymer and perovskite mixed solution with a perovskite mass fraction of 1-90% (preferably 10%, 30%, 40%, 50%, 65%, 80%, 85%, 90%) is converted into aerosol droplets using an ultrasonic atomizer with a power of 10-100W (preferably 50W).
[0017] The spraying method is selected from ultrasonic spraying, compressed air spraying, etc. (the embodiment of the present invention uses ultrasonic spraying).
[0018] The steps of depositing the aerosol droplets on the dried substrate by spraying and repeatedly depositing multiple times (1 to 1000 times, preferably 15 times) are as follows:
[0019] The aerosol droplets are delivered to the nozzle at a pressure of 0.5-1 psi (preferably 0.9 psi) using air as the carrier gas. The nozzle is programmed to move at a speed of 5-20 mm·s -1 (Preferably 10 mm·s -1 ) on the dried substrate, with the following settings: height of 20-50 mm (preferably 30 mm), substrate temperature of 100-150 °C (preferably 120, 150 °C), flow rate of 10-30 mL·h -1 (Preferably 24 mL·h -1 ), spray once; anneal (10-30 seconds, preferably 20 seconds) at a temperature of 100-150 ° C (preferably 120, 150 ° C) and then perform the next cycle, depositing layer by layer multiple times (1-1000 times, preferably 15 times).
[0020] The electrode material is at least one of silver, gold, aluminum, copper, and chromium, and has a thickness of 5 to 300 nm, preferably 100 nm.
[0021] The distance between the electrodes is 50-200 μm (preferably 100 μm), and the electrode width is 0.5-2 mm (preferably 1 mm).
[0022] The preparation steps of the CsPbBr3 perovskite storage solution are as follows: cesium bromide and lead bromide with a molar ratio of 1:1 are dissolved in a DMF and DMSO solution, and the volume ratio of DMF and DMSO is 7:3 to obtain a CsPbBr3 perovskite storage solution with a concentration of 0.05~2 mol / L (preferably 0.12 mol / L).
[0023] The preparation steps of the MAPbBr3 perovskite storage solution are as follows:
[0024] Methylammonium bromide and lead bromide at a molar ratio of 1:1 are dissolved in DMSO to obtain a MAPbBr3 perovskite storage solution with a concentration of 0.05~2 mol / L (preferably 1.5 mol / L).
[0025] The preparation steps of the FAPbI3 perovskite storage solution are as follows:
[0026] Formamidine hydroiodide and lead iodide in a molar ratio of 1:1 are dissolved in a DMF and DMSO solution, and the volume ratio of DMF and DMSO is 4:1 to obtain a FAPbI3 perovskite storage solution with a concentration of 0.05~2 mol / L (preferably 1.55 mol / L).
[0027] The second aspect of the present invention provides an application of an X-ray detector based on an ultra-flexible layered polymer perovskite composite film prepared by the method in the preparation of wearable sensors, soft robots, and implantable devices.
[0028] Due to the adoption of the above technical solution, the present invention has the following advantages and beneficial effects:
[0029] The X-ray detector based on the ultra-flexible layered polymer perovskite composite film provided by the present invention can assemble a polymer / perovskite mixed precursor solution into a special structure in which polymers and perovskites are stacked layer by layer by a spraying method. The method is simple to operate and has high repeatability.
[0030] The X-ray detector based on the ultra-flexible layered polymer perovskite composite film provided by the present invention adopts a spraying method, can be expanded to the preparation of large-area devices, is not limited by the shape of the substrate, and has a wide range of applications.
[0031] The X-ray detector based on the ultra-flexible layered polymer perovskite composite film provided by the present invention has ultra-flexibility and fatigue resistance. The layered structure effectively releases the strain caused by deformation, reduces the influence of mechanical deformation on photoelectric performance, and realizes the accuracy and stability of the detector detection performance during dynamic detection.
[0032] The X-ray detector based on the ultra-flexible layered polymer perovskite composite film provided by the present invention can achieve the regulation of the polymer thickness between the composite film layers and the degree of conductivity of the perovskite within the layer by regulating the ratio between the polymer and the perovskite, and further achieve the regulation of the flexibility and photoelectric properties of the film, thereby obtaining an ultra-flexible, fatigue-resistant, highly sensitive and stable X-ray detector.
[0033] The X-ray detector based on the ultra-flexible layered polymer perovskite composite film provided by the present invention retains the high sensitivity detection performance of the perovskite itself, and achieves sensitive detection of X-rays and a low limit detection dose rate.
[0034] The X-ray detector based on the ultra-flexible layered polymer perovskite composite film provided by the present invention can be used for stable X-ray detection under extreme bending conditions and wearable dynamic detection. BRIEF DESCRIPTION OF THE DRAWINGS
[0035] Figure 1 Schematic diagram of the layered structure of a large-area X-ray detector based on ultra-flexible layered polymer perovskite composite film.
[0036] Figure 2 Schematic diagram of the nanoindentation comparison results of the composite film in Example 1, the pure perovskite film and the polyimide film in Comparative Example 1, where the inset is a test schematic diagram.
[0037] Figure 3 Schematic diagram comparing the XRD patterns of the composite film of Comparative Example 1 (left figure) and Example 1 (middle figure) under different stress conditions.
[0038] Figure 4 It is a schematic diagram of the detection sensitivity fitting curve of the X-ray detector.
[0039] Figure 5 This is a schematic diagram of wearable real-time detection of X-ray detectors.
[0040] Figure 6 It is a schematic diagram of the real-time detection response curve of the wearable X-ray detector.
[0041] Figure 7 This is a schematic diagram of the curve showing how the detection sensitivity of the X-ray detector changes with the number of bends.
[0042] Figure 8Schematic diagram of the cross-section SEM of composite films prepared from polymer and perovskite mixed solutions with different perovskite mass fractions (30%, 50%, 65%, 90%).
[0043] Figure 9 Schematic diagram of the resistivity of composite thin film X-ray detectors prepared from mixed solutions of polymer and perovskite with different perovskite mass fractions (0%, 10%, 30%, 40%, 50%, 65%, 80%, 85%, 90%) measured by voltammetry. DETAILED DESCRIPTION
[0044] In order to explain the present invention more clearly, the present invention is further described below in conjunction with preferred embodiments. Those skilled in the art should understand that the following specific description is illustrative rather than restrictive and should not be used to limit the scope of protection of the present invention.
[0045] Example 1
[0046] Preparation of polymer and perovskite mixed solution:
[0047] Using an analytical balance, cesium bromide (2.4 mmol, 0.5107 g) and lead bromide (2.4 mmol, 0.8808 g) were dissolved in 20 mL of DMF and DMSO solution (the volume ratio of DMF to DMSO was 7:3) to obtain a CsPbBr3 perovskite stock solution with a concentration of 0.12 mol / L.
[0048] To 15 mL of a 20% solids polyimide stock solution (purchased from Yijia Plastics Co., Ltd.), 5 mL of DMF was added and stirred for 6 hours to obtain a 15% solids polymer stock solution. Then, 4 mL of a 0.12 mol / L CsPbBr3 perovskite stock solution and 1 mL of a 15% solids polymer stock solution were mixed to obtain a polymer-perovskite mixed solution with a 65% perovskite mass fraction.
[0049] The preparation method of the X-ray detector based on the ultra-flexible layered polymer perovskite composite film comprises the following steps:
[0050] The glass substrate was ultrasonically cleaned three times with deionized water, acetone, and ethanol in sequence, and then dried until the solvent and water were completely removed to obtain a dried glass substrate.
[0051] The dried glass substrate was treated with a UV ozone machine for 15 minutes, and a mixed solution of polymer and perovskite with a mass fraction of 65% was converted into aerosol droplets in an ultrasonic atomizer (power 50 W) and transported to the nozzle at a pressure of 0.9 psi (about 6.2 kPa) using air as the carrier gas. The nozzle was programmed to move at a speed of 10 mm·s -1 The speed of the liquid was moved on the dried glass substrate, and the settings were: height 30 mm, substrate temperature 150 °C, flow rate 24 mL·h -1 , sprayed once. Annealing was performed at 150°C for 20 seconds before the next cycle. After 15 spraying cycles, the composite film was removed from the glass substrate to obtain a composite film with an average thickness of approximately 20 microns. Lateral silver counter electrodes were deposited using a dual-source co-evaporation method (performed using a vacuum evaporation coater, requiring a controlled heating current of 120 A and a evaporation time of 30 minutes). The counter electrode spacing was 100 μm, the electrode width was 1 mm, and the electrode thickness was controlled to 100 nm, resulting in an X-ray detector based on an ultra-flexible layered polymer perovskite composite film.
[0052] Comparative Example 1
[0053] Preparation method of pure perovskite film:
[0054] The glass substrate was ultrasonically cleaned three times with deionized water, acetone, and ethanol in sequence, and then dried until the solvent and water were completely removed to obtain a dried glass substrate.
[0055] After drying, the glass substrate was treated with a UV ozone machine for 15 minutes, and the CsPbBr3 perovskite stock solution with a concentration of 0.12 mol / L was converted into aerosol droplets in an ultrasonic atomizer (power 50 W) and transported to the nozzle with air as the carrier gas at a pressure of 0.9 psi (about 6.2 kPa). The nozzle was programmed to move at a speed of 10 mm·s -1 The speed of the liquid was moved on the dried glass substrate, and the settings were: height 30 mm, substrate temperature 150 °C, flow rate 24 mL·h -1 , spray once. Anneal at 150°C for 20 seconds before the next cycle. After 15 spray cycles, a pure perovskite film was obtained.
[0056] Figure 1 Schematic diagram of the layered structure of a large-area X-ray detector based on an ultra-flexible layered polymer perovskite composite film. The composite film presents an overlapping layered structure of polyimide and perovskite.
[0057] Figure 2 Schematic diagram of the nanoindentation comparison results of the composite film in Example 1, the pure perovskite film and the polyimide film in Comparative Example 1, where the inset is a test schematic diagram.
[0058] Preparation method of polyimide film:
[0059] The glass substrate was ultrasonically cleaned three times with deionized water, acetone, and ethanol in sequence, and then dried until the solvent and water were completely removed to obtain a dried glass substrate.
[0060] The dried glass substrate was treated with an ultraviolet ozone machine for 15 minutes, and 60 μL of polyimide mother solution with a solid mass fraction of 20% was taken to prepare a polyimide film by spin coating. The spin coating parameters were: 3000 rpm, 30 seconds, annealing at 100 °C for 30 minutes, and then removed from the substrate to obtain a polyimide film.
[0061] The test method is as follows:
[0062] The hardness and modulus of the films were measured using a nanoindenter (Bruker Hysitron TI 950) using a Buchholz indenter under a 1.5 mN load control mode. The Young's moduli of the composite film in Example 1, the pure perovskite film in Comparative Example 1, and the polyimide film were 5.411 GPa, 20.828 GPa, and 3.585 GPa, respectively. The hardnesses of the composite film in Example 1, the pure perovskite film in Comparative Example 1, and the polyimide film were 0.461 GPa, 0.646 GPa, and 0.416 GPa, respectively. The addition of polyimide significantly reduced the hardness and Young's modulus of the composite film compared to the pure perovskite film, demonstrating the flexibility of the composite film in Example 1.
[0063] Figure 3 Schematic diagram of the comparison of XRD spectra of Comparative Example 1 (left figure) and the composite film of Example 1 (middle figure) under different stress conditions. In the figure, the right figure is a schematic diagram of the comparison of the degree of peak position displacement of the pure perovskite film in Comparative Example 1 and the composite film of Example 1, taking the (100) crystal plane as an example. It can be seen from the figure that the peak position of the perovskite (100) crystal plane in the composite film of Example 1 does not change significantly with deformation, while the peak position of Comparative Example 1 has obvious displacement, indicating that the composite film of Example 1 has good strain release ability.
[0064] Figure 4 Figure 2 is a schematic diagram of the X-ray detector's sensitivity fitting curve. The test method is as follows: During X-ray detection, the composite film was exposed to a Cu X-ray tube (Canon, A40) at a tube voltage of 40 kV. The dose rate was controlled by adjusting the tube current (2–40 mA) and the aluminum foil thickness (64 layers). The dose rate was calibrated using a RaySafe X2 R / F sensor. The X-ray response current was measured using a Keithley 2400 SourceMeter instrument. Sensitivity (S) can be calculated using the following formula:
[0065]
[0066] Where I is the response current and A is the effective area, which is 0.0314 cm 2 .
[0067] The signal-to-noise ratio (SNR) can be calculated using the following formula:
[0068]
[0069] Among them, J on is the current density of X-ray irradiation, J n is the noise current density, J i It's J on The instantaneous value of .
[0070] At 500 V·cm -1 Under the electric field strength of , the detection sensitivity is 8380.80 μC·Gy air -1 cm -2 The detection limit dose rate corresponding to the lowest detection of the X-ray detector (SNR=3) is a low 26.37 nGy air ·s -1 , indicating that the composite thin film detector has excellent detection performance.
[0071] Figure 5 This is a schematic diagram of a wearable X-ray detector for real-time detection. The testing method is as follows: The X-ray detector based on the ultra-flexible layered polymer perovskite composite film prepared in this invention is fixed to the joints of a robotic arm. During the detection process, the robotic arm opens and closes, and a Keithley 2400 digital source meter is used to measure the X-ray response current. The detector monitors the current intensity in real time during the dynamic opening and closing of the robotic arm.
[0072] Figure 6 This is a schematic diagram of the wearable real-time detection response curve of an X-ray detector. The upper left figure shows the radiation current measured with the manipulator in the dynamic state of opening and closing. The lower left figure records the current changes when the manipulator is held open or clenched, respectively, toggling the X-ray on and off. As can be seen in the right figure, the radiation current measured in the dynamic state is not significantly different from the static state, demonstrating that the ultra-flexible layered polymer perovskite composite film-based X-ray detector prepared by this invention has the capability of wearable real-time detection.
[0073] Figure 7Figure 2 is a graph showing how the sensitivity of an X-ray detector changes with the number of bends. Under extreme bending conditions of 1.5 mm, the X-ray detector based on the ultra-flexible layered polymer perovskite composite film was bent and restored multiple times, with sensitivity measured at regular intervals. After 30,000 bends, the sensitivity of the X-ray detector based on the ultra-flexible layered polymer perovskite composite film prepared by the present invention remained at 97.4% of its initial sensitivity, demonstrating the ultra-flexibility and fatigue resistance of the X-ray detector based on the ultra-flexible layered polymer perovskite composite film prepared by the present invention.
[0074] Example 2
[0075] Mix 2 mL of 0.12 mol / L CsPbBr3 perovskite stock solution and 1 mL of 15% solid mass fraction polymer stock solution to obtain a polymer and perovskite mixed solution with a perovskite mass fraction of 50%.
[0076] The preparation method of the X-ray detector based on the ultra-flexible layered polymer perovskite composite film is the same as that in Example 1.
[0077] Example 3
[0078] Mix 0.9 mL of 0.12 mol / L CsPbBr3 perovskite stock solution and 1 mL of 15% solid mass fraction polymer stock solution to obtain a polymer and perovskite mixed solution with a perovskite mass fraction of 30%.
[0079] Mix 16 mL of 0.12 mol / L CsPbBr3 perovskite stock solution and 1 mL of 15% solid mass fraction polymer stock solution to obtain a polymer and perovskite mixed solution with a perovskite mass fraction of 90%.
[0080] The preparation method of the X-ray detector based on the ultra-flexible layered polymer perovskite composite film is the same as that in Example 1.
[0081] Figure 8The following are cross-sectional SEM diagrams of composite films prepared from polymer-perovskite mixed solutions with different perovskite mass fractions (30%, 50%, 65%, and 90%). As can be seen from the figure, as the perovskite mass fraction increases, the perovskite layers within the composite film change from being independently dispersed (composite film prepared from a polymer-perovskite mixed solution with a perovskite mass fraction of 30%) to gradually becoming conductive, and the thickness of the interlayer polymer layer gradually decreases. The composite film of Example 2 (composite film prepared from a polymer-perovskite mixed solution with a perovskite mass fraction of 50%) exhibits a clear layered structure. The composite film of Example 1 (composite film prepared from a polymer-perovskite mixed solution with a perovskite mass fraction of 65%) exhibits a layered structure of overlapping polyimide and perovskite. The composite film prepared from a polymer-perovskite mixed solution with a perovskite mass fraction of 90% exhibits complete internal conductivity, and the layered structure disappears.
[0082] Example 4
[0083] Mix 8 mL of 0.12 mol / L CsPbBr3 perovskite stock solution and 1 mL of 15% solid mass fraction polymer stock solution to obtain a polymer and perovskite mixed solution with a perovskite mass fraction of 80%.
[0084] The preparation method of the X-ray detector based on the ultra-flexible layered polymer perovskite composite film is the same as that in Example 1.
[0085] Example 5
[0086] Mix 0 mL of 0.12 mol / L CsPbBr3 perovskite stock solution and 1 mL of 15% solid mass fraction polymer stock solution to obtain a polymer and perovskite mixed solution with a perovskite mass fraction of 0%.
[0087] Mix 0.25 mL of 0.12 mol / L CsPbBr3 perovskite stock solution and 1 mL of 15% solid mass fraction polymer stock solution to obtain a polymer and perovskite mixed solution with a perovskite mass fraction of 10%.
[0088] Mix 1.4 mL of 0.12 mol / L CsPbBr3 perovskite stock solution and 1 mL of 15% solid mass fraction polymer stock solution to obtain a polymer and perovskite mixed solution with a perovskite mass fraction of 40%.
[0089] Mix 12 mL of 0.12 mol / L CsPbBr3 perovskite stock solution and 1 mL of 15% solid mass fraction polymer stock solution to obtain a polymer and perovskite mixed solution with a perovskite mass fraction of 85%.
[0090] The preparation method of the X-ray detector based on the ultra-flexible layered polymer perovskite composite film is the same as that in Example 1.
[0091] Figure 9 Schematic diagram of the resistivity of composite thin-film X-ray detectors fabricated from polymer-perovskite mixed solutions with varying perovskite mass fractions (0%, 10%, 30%, 40%, 50%, 65%, 80%, 85%, and 90%), measured using voltammetry. The inset shows the lateral X-ray detector structure. The figure shows three phases of resistivity. The first phase exhibits high resistivity, corresponding to a composite film structure with independently dispersed perovskites. The second phase exhibits a sharp drop in resistivity, corresponding to a conductive perovskite layer and significantly improved photoelectric performance. The third phase sees the resistivity stabilize, corresponding to complete conductivity within the composite film. X-ray detectors based on ultra-flexible layered polymer-perovskite composite films combine exceptional flexibility with excellent electrical performance.
[0092] Example 6
[0093] Preparation of polymer and perovskite mixed solution
[0094] Using an analytical balance, methylammonium bromide (2.4 mmol, 0.2687 g) and lead bromide (2.4 mmol, 0.8808 g) were dissolved in 1.6 mL of DMSO to obtain a MAPbBr3 perovskite stock solution with a concentration of 1.5 mol / L.
[0095] 5 mL of DMF was added to 15 mL of a 20% solids polyimide stock solution and stirred for 6 hours to obtain a 15% solids polymer stock solution. 1.6 mL of a 1.5 mol / L MAPbBr3 perovskite stock solution and 4 mL of a 15% solids polymer stock solution were mixed to obtain a polymer-perovskite mixed solution with a 65% perovskite mass fraction.
[0096] The preparation method of the X-ray detector based on the ultra-flexible layered polymer perovskite composite film comprises the following steps:
[0097] The glass substrate was ultrasonically cleaned three times with deionized water, acetone, and ethanol in sequence, and then dried until the solvent and water were completely removed to obtain a dried glass substrate.
[0098] The dried glass substrate was treated with a UV ozone machine for 15 minutes, and a mixed solution of polymer and perovskite with a mass fraction of 65% was converted into aerosol droplets in an ultrasonic atomizer (power 50 W) and transported to the nozzle at a pressure of 0.9 psi (about 6.2 kPa) using air as the carrier gas. The nozzle was programmed to move at a speed of 10 mm·s -1The speed of the liquid was moved on the dried glass substrate, and the settings were: height 30 mm, substrate temperature 120 °C, flow rate 24 mL·h -1 , sprayed once. Annealing was performed at 120°C for 20 seconds before the next cycle. After 15 spraying cycles, the composite film was removed from the glass substrate to obtain a composite film with an average thickness of approximately 20 microns. Lateral silver counter electrodes were deposited using a dual-source co-evaporation method (performed using a vacuum evaporation coating apparatus, requiring a controlled heating current of 120 A and an evaporation time of 30 minutes). The counter electrode spacing was 100 μm, the electrode width was 1 mm, and the electrode thickness was controlled to 100 nm, resulting in an X-ray detector based on an ultra-flexible layered polymer perovskite composite film.
[0099] Example 7
[0100] Preparation of polymer and perovskite mixed solution
[0101] Formamidine hydroiodide (2.48 mmol, 0.4265 g) and lead iodide (2.48 mmol, 1.1433 g) were weighed using an analytical balance and dissolved in 1.6 mL of DMF and DMSO solution (the volume ratio of DMF to DMSO was 4:1) to obtain a FAPbI3 perovskite stock solution with a concentration of 1.55 mol / L.
[0102] 5 mL of DMF was added to 15 mL of a 20% solids polyimide stock solution and stirred for 6 hours to obtain a 15% solids polymer stock solution. 1.6 mL of a 1.55 mol / L FAPbI3 perovskite stock solution and 5.5 mL of a 15% solids polymer stock solution were mixed to obtain a polymer-perovskite mixed solution with a 65% perovskite mass fraction.
[0103] The preparation method of the X-ray detector based on the ultra-flexible layered polymer perovskite composite film is the same as that in Example 1.
[0104] The above description is merely a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Although the present invention has been disclosed as above in terms of a preferred embodiment, it is not intended to limit the present invention. Any technician familiar with the present invention can make slight changes or modifications to equivalent embodiments using the above-mentioned technical contents without departing from the scope of the technical solution of the present invention. However, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the solution of the present invention.
Claims
1. A method for preparing an X-ray detector based on an ultra-flexible layered polymer perovskite composite film, characterized in that: The following steps are involved: The perovskite storage solution and the polymer storage solution with a solid mass fraction of 5 to 20% are mixed to obtain a polymer and perovskite mixed solution with a perovskite mass fraction of 1 to 90%; The dried substrate is treated with ultraviolet ozone to convert a mixed solution of polymer and perovskite with a perovskite mass fraction of 1 to 90% into aerosol droplets. The aerosol droplets are deposited on the dried substrate by spraying. The deposition is repeated multiple times. The film is removed from the substrate and a lateral counter electrode is deposited by a dual-source co-evaporation method to obtain an X-ray detector based on an ultra-flexible layered polymer perovskite composite film. The polymer is selected from polyimide and polyvinyl pyrrolidone; The perovskite is selected from CH3NH3PbI3, CH3NH3PbBr3, CH(NH2)2PbI3, CsPbBr3, Cs x FA y MA 1-x- y PbI z Br 3-z 、Cs x MA 1-x PbI y Br 3-y 、Cs x FA 1-x PbI y Br 3-y , FA x MA 1-x PbI y Br 3-y 、CsPbI x Br 3-x , Cs2AgBiBr6, the x value range of ternary perovskite is 0~1, the y value range is 0~1, and the z value range is 0~3; the x value range of binary perovskite is 0~1, the y value range is 0~3, and the x value range of mono-perovskite is 0~3.
2. The method for preparing an X-ray detector based on an ultra-flexible layered polymer perovskite composite film according to claim 1, wherein: The preparation method of the polymer storage solution is as follows: DMF was added to the polyimide mother solution and stirred thoroughly to obtain a polymer stock solution with a solid mass fraction of 5-20%.
3. The method for preparing an X-ray detector based on an ultra-flexible layered polymer perovskite composite film according to claim 1, wherein: The preparation steps of the dried substrate are as follows: the substrate is repeatedly ultrasonically cleaned at least three times with deionized water, acetone, and ethanol in sequence, and dried to obtain a dried substrate; The substrate is selected from a glass substrate, a silver substrate, and a copper substrate.
4. The method for preparing an X-ray detector based on an ultra-flexible layered polymer perovskite composite film according to claim 1, wherein: The polymer and perovskite mixed solution with a perovskite mass fraction of 1-90% is converted into aerosol droplets using an ultrasonic atomizer with a power of 10-100W; The spraying method is selected from ultrasonic spraying and compressed air spraying.
5. The method for preparing an X-ray detector based on an ultra-flexible layered polymer perovskite composite film according to claim 1, wherein: The steps of depositing the aerosol droplets on the dried substrate by spraying and repeatedly depositing the aerosol droplets are as follows: The aerosol droplets are transported to the nozzle with air as carrier gas at a pressure of 0.5-1 psi, and the nozzle is programmed to spray at a speed of 5-20 mm·s -1 The speed of the liquid was moved on the dried substrate, and the settings were: height 20-50 mm, substrate temperature 100-150 °C, flow rate 10-30 mL·h -1 , spray once; anneal at a temperature of 100~150 ℃ and then proceed to the next cycle, depositing layer by layer multiple times.
6. The method for preparing an X-ray detector based on an ultra-flexible layered polymer perovskite composite film according to claim 1, wherein: The electrode material is at least one of silver, gold, aluminum, copper, and chromium, and has a thickness of 5 to 300 nm; The distance between the electrodes is 50-200 μm, and the electrode width is 0.5-2 mm.
7. The method for preparing an X-ray detector based on an ultra-flexible layered polymer perovskite composite film according to claim 1, wherein: The preparation steps of the CsPbBr3 perovskite storage solution are as follows: cesium bromide and lead bromide with a molar ratio of 1:1 are dissolved in a DMF and DMSO solution with a volume ratio of DMF and DMSO of 7:3 to obtain a CsPbBr3 perovskite storage solution with a concentration of 0.05~2 mol / L.
8. The method for preparing an X-ray detector based on an ultra-flexible layered polymer perovskite composite film according to claim 1, wherein: The preparation steps of the MAPbBr3 perovskite storage solution are as follows: Methylammonium bromide and lead bromide at a molar ratio of 1:1 were dissolved in DMSO to obtain a MAPbBr3 perovskite storage solution with a concentration of 0.05~2 mol / L.
9. The method for preparing an X-ray detector based on an ultra-flexible layered polymer perovskite composite film according to claim 1, wherein: The preparation steps of the FAPbI3 perovskite storage solution are as follows: Formamidine hydroiodide and lead iodide in a molar ratio of 1:1 were dissolved in DMF and DMSO solution, and the volume ratio of DMF and DMSO was 4:1 to obtain a FAPbI3 perovskite storage solution with a concentration of 0.05~2 mol / L.
10. Use of an X-ray detector based on an ultra-flexible layered polymer perovskite composite film prepared by the method according to any one of claims 1 to 9 in the preparation of wearable sensors, soft robots, and implantable devices.