Black phosphorus heterojunction water-blocking and oxygen-blocking coating and preparation method thereof

Abstract

The application belongs to the technical field of functional coating and specifically provides a black phosphorus heterojunction water-blocking and oxygen-blocking coating and a preparation method thereof, which comprises the following steps: 1) mixing chloroform and DMF, adding bulk BP for ultrasonic treatment, collecting supernatant by centrifugation, and drying to obtain BP nanosheets; dispersing the BP nanosheets into a mixture of ethanol, water and SDBS, adding ammonia hydroxide, HCHO and NiCl2 after stirring, and then performing a reaction by heating, collecting the solid by centrifugation, and washing to obtain a base material; 2) drying the base material, placing it into a sealed container containing silicone oil, and performing a reaction by heating; transferring it into chloroform containing 1,12-dodecylamine for a reaction; then transferring it into acetone for immersion, taking it out, blowing dry, and obtaining a barrier material; 3) transferring the barrier material to the surface of a substrate to obtain a coating. The coating prepared by the application can effectively block the erosion of oxygen and water molecules on the black phosphorus heterojunction, so that the black phosphorus heterojunction can maintain better infrared detection performance and stability.

Description

Technical Field

[0001] This application belongs to the field of functional coating technology, and in particular relates to a black phosphorus heterojunction water-blocking and oxygen-barrier coating and its preparation method. Background Technology

[0002] Infrared detectors have wide applications in fields such as medical imaging and environmental monitoring. Traditional bulk semiconductors and novel nanomaterials have been used to develop infrared detectors with high responsivity, speed, efficiency, and wide detection wavelengths. Among all these materials, low-cost two-dimensional nanomaterials have attracted great attention due to their excellent optical, electrical, and mechanical properties.

[0003] Black phosphorus is a two-dimensional layered direct bandgap semiconductor with a thickness-adjustable direct bandgap and excellent light absorption and responsivity. It shows potential as a core material for photodetectors in the visible and infrared bands, making it a promising candidate for photodetection from visible light to mid-infrared. However, the layered structure of black phosphorus contains lone pairs of electrons that are highly reactive and do not participate in bonding. These lone pairs readily undergo irreversible oxidation reactions with oxygen and water vapor in the air, leading to insufficient device stability under humid conditions.

[0004] Patent application CN115911159A discloses a two-dimensional flexible infrared detector based on photothermal effect and its fabrication method. The infrared detector, fabricated using a polyimide substrate, combines high flexibility with low thermal conductivity, making it suitable for applications such as wearable devices and flexible sensors where rigid detectors cannot be applied. Furthermore, the patent utilizes atomic layer deposition (ALD) technology to coat the black phosphorus layer and the device surface with Al2O3, improving device durability by blocking the contact between water and oxygen and black phosphorus. However, Al2O3 is an inorganic rigid film, which is prone to microcracks during bending, expanding the water and oxygen permeation path and weakening durability. Additionally, patent application CN108550640A discloses a broadband black phosphorus photodetector based on cadmium telluride nanocrystals and its fabrication method. Through a composite structure of "cadmium telluride layer + black phosphorus sheet layer," it overcomes the limitation of single black phosphorus focusing solely on infrared detection, achieving a broadband response. However, this patent only reduces the contact area between black phosphorus and oxygen and water vapor by stacking cadmium telluride layer and black phosphorus sheet layer, which cannot completely solve the problem of black phosphorus being easily oxidized and makes it difficult to ensure the normal operation of black phosphorus for a long time. Summary of the Invention

[0005] To address the aforementioned issues and further improve the infrared detection performance and stability of black phosphorus-based heterojunctions, this application provides a water-blocking and oxygen-barrier coating for black phosphorus heterojunctions and its preparation method.

[0006] This application first provides a method for preparing a black phosphorus heterojunction water-blocking and oxygen-barrier coating, using the following technical solution: A method for preparing a black phosphorus heterojunction water-blocking and oxygen-barrier coating includes the following steps: 1) Mix chloroform and DMF evenly, add lumpy BP and sonicate, collect the supernatant by centrifugation, and vacuum dry to obtain BP nanosheets; disperse BP nanosheets in a mixture containing ethanol, water and SDBS, add ammonium hydroxide, HCHO and NiCl2 under stirring and heat to react, collect the solid by centrifugation and wash with ethanol to obtain the base material; 2) After the base material is naturally dried, it is placed in a sealed container containing silicone oil and heated; then, it is transferred to chloroform containing 1,12-dodecaneamine for reaction; after the reaction is completed, it is transferred to acetone for immersion, and then removed and dried with nitrogen to obtain the barrier material. 3) A coating is obtained by transferring the barrier material to the substrate surface through a condensation process.

[0007] Furthermore, the condensate membrane is made of a material comprising the following components: polyvinyl alcohol, PDMAEMA, and water.

[0008] Furthermore, in step 1), the temperature of the heating reaction is 40-80℃, and the reaction time is 1-3h.

[0009] Furthermore, in step 2), the reaction temperature is 80-120℃ and the reaction time is 15-45 min.

[0010] Furthermore, the NiCl2 is an aqueous solution with a concentration of 0.05-0.2M.

[0011] Furthermore, the substrate includes a substrate and a black phosphorus heterojunction disposed on the substrate.

[0012] Furthermore, the substrate includes a silicon layer and a silicon dioxide layer disposed on the silicon layer.

[0013] Furthermore, the thickness of the silicon layer is 300-500 μm.

[0014] Furthermore, the thickness of the silicon dioxide layer is 200-400 nm.

[0015] This application also provides a black phosphorus heterojunction water-blocking and oxygen-barrier coating, which is prepared by the above-described preparation method.

[0016] Compared with the prior art, this application has the following beneficial effects: 1. The coating component prepared in this application is obtained by depositing Ni nanoparticles on the surface of BP nanosheets. The Ni nanoparticles can form NiP on the surface of BP nanosheets. x O yThe complex can effectively passivate the unsaturated P atoms on the BP surface, preventing them from reacting with oxygen and water vapor, thereby improving its stability; in addition, the high conductivity of Ni can accelerate charge transport, which is beneficial to the separation of photogenerated electron-hole pairs, resulting in a significant improvement in the responsivity of the infrared band and a significant reduction in response time.

[0017] 2. The coating prepared in this application forms a protective layer on the surface of the black phosphorus heterojunction in a directional manner. This not only physically isolates oxygen and moisture through the steric hindrance effect of the long-chain alkyl groups, preventing water and oxygen from contacting the unsaturated P atoms on the BP surface, but also passivates the defect sites of BP, preventing P atoms from being oxidized to form P. x O y At the same time, it does not damage the original pleated honeycomb structure and intrinsic activity of BP, and significantly improves the stability of black phosphorus heterojunction in use.

[0018] 3. The coating structure prepared in this application is a two-step design of first loading Ni and then modifying the protective layer. The introduction of Ni will regulate the electron cloud distribution on the surface of BP nanosheets, which is conducive to the generation of higher density hydroxyl sites on the surface of BP in subsequent reactions, thereby improving the reaction efficiency of 1,12-dodecaneamine. The protective layer formed by 1,12-dodecaneamine not only protects BP but also isolates water and oxygen from corroding Ni nanoparticles, thus maintaining the high conductivity and interfacial charge transport efficiency of black phosphorus heterostructure for a long time. Attached Figure Description

[0019] Figure 1 The results show the photoresponse performance of the coating-bonded black phosphorus heterojunction in Examples 1-3 and Control Groups 1-2 of this application.

[0020] Figure 2 The results show the stability performance test results of the coating-bonded black phosphorus heterojunction in Examples 1-3 and Control Groups 1-2 of this application. Detailed Implementation

[0021] To make the inventive objectives, technical solutions, and beneficial effects of this application clearer, the following detailed description is provided in conjunction with embodiments. Obviously, the described embodiments are only a portion of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0022] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0023] When using “including,” “having,” and “contains” as described herein, the intention is to cover non-exclusive inclusion, unless an explicit qualifying term such as “only,” “consisting of,” etc., is used, in which case another component may be added.

[0024] The terms "preferred," "more preferably," "better," and "even better" used in this application refer to embodiments of this application that provide certain beneficial effects under certain circumstances. However, other embodiments may also be preferred under the same or other circumstances. Furthermore, the description of one or more preferred embodiments does not imply that other embodiments are unavailable, nor is it intended to exclude other embodiments from the scope of this application. That is, in this application, "preferred," "more preferably," "better," and "even better" are merely descriptions of implementations or embodiments with better effects, but do not constitute a limitation on the scope of protection of this application.

[0025] In this application, terms such as "further," "even more," and "particularly" are used for descriptive purposes and indicate differences in content, but should not be construed as limiting the scope of protection of this application.

[0026] In this application, "at least one" means one or more, such as one, two, or more. "Multiple" or "several" means at least two, such as two, three, etc., and "multi-layered" means at least two layers, such as two layers, three layers, etc., unless otherwise explicitly specified. In the description of this application, "several" means at least one, such as one, two, etc., unless otherwise explicitly specified.

[0027] When a numerical range is disclosed herein, the range is considered continuous and includes the minimum and maximum values ​​of the range, as well as every value between the minimum and maximum values. Furthermore, when the range refers to integers, it includes every integer between the minimum and maximum values ​​of the range. Additionally, when multiple ranges are provided to describe a feature or characteristic, the ranges may be combined. In other words, unless otherwise specified, all ranges disclosed herein should be understood to include any and all subranges to which they are incorporated.

[0028] Unless otherwise specified, all steps in this application may be performed sequentially or randomly. For example, the method comprising steps (a) and (b) indicates that the method may include steps (a) and (b) performed sequentially, or it may include steps (b) and (a) performed sequentially. For example, the mention that the method may also include step (c) indicates that step (c) may be added to the method in any order; for example, the method may include steps (a), (b), and (c), or it may include steps (a), (c), and (b), or it may include steps (c), (a), and (b), etc. Unless otherwise stated, singular terms may include plural forms and should not be construed as having a quantity of one.

[0029] In this application, "above" or "below" includes the number itself. For example, "below 1" includes 1.

[0030] In this application, room temperature refers to 0~40℃, including but not limited to 10~40℃, or further to 20~30℃.

[0031] The present application will be further illustrated by the following examples, but these examples do not limit the scope of the present application.

[0032] When numerical ranges are given in the embodiments, it should be understood that, unless otherwise stated in this application, both endpoints of each numerical range and any value between the two endpoints may be selected. Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. All reagents or instruments whose manufacturers are not specified are conventional products that can be purchased commercially. In addition to the specific methods, equipment, and materials used in the embodiments, based on the knowledge of the prior art possessed by one of ordinary skill in the art and the description in this application, any prior art methods, equipment, and materials similar to or equivalent to those described, used, or made by the methods, equipment, and materials in the embodiments of this application may be used to implement this application.

[0033] Example 1 The method for preparing the black phosphorus heterojunction water-blocking and oxygen-barrier coating in this embodiment includes the following steps: 1) Mix 50 mL of chloroform and 50 mL of LDMF evenly, add 500 mg of block BP, and sonicate for 2 h after passing argon gas for 30 min. Collect the supernatant by centrifugation and dry it under vacuum at 60 °C for 12 h to obtain BP nanosheets. 27 mg of BP nanosheets were dispersed in a mixture containing 160 mL of ethanol, 240 mL of water and 1.2 g of SDBS. 60 µL of ammonium hydroxide solution, 750 µL of HCHO solution and 3 mL of 0.1 M NiCl2 solution were added under stirring. After purging with nitrogen for 1 h, the temperature was raised to 60 °C and reacted for 2 h. The solid was collected by centrifugation and washed three times with ethanol to obtain the base material. 2) After the base material is naturally dried, it is placed in a sealed container containing silicone oil and heated to 130℃ for 20 min. Then, it is transferred to 50 mL of chloroform solution containing 0.5 g of 1,12-dodecaneamine and reacted at 100℃ for 30 min. After the reaction is completed, the sample is taken out and soaked in 50℃ warm acetone for 1 h to remove unreacted 1,12-dodecaneamine. After drying with nitrogen, the barrier material is obtained. 3) Dissolve 0.8g of PVA powder in 92mL of deionized water at 90℃ and stir for 4h until completely transparent. Cool to room temperature, then slowly add 10mL of ethanol solution containing 0.5g of PDMAEMA. After uniform dispersion, add the barrier material and 0.15mL of 25% glutaraldehyde solution, followed by 0.5mL of 1M HCl. Continue stirring for 1h to obtain a spin-coating solution for a gel film. Then, spin-coate the gel film solution evenly onto the substrate surface and cure it at 60℃ to obtain a gel film. Then, transfer the entire solution to 0.1M sodium bicarbonate buffer solution to dissolve the gel film. At this point, the barrier material binds to the substrate surface to form a coating.

[0034] The coating thickness in this embodiment is 25 nm.

[0035] The substrate of this embodiment includes a substrate and a black phosphorus heterojunction disposed on the substrate. The substrate includes a silicon layer and a silicon dioxide layer. The thickness of the silicon layer is 400 μm and the thickness of the silicon dioxide layer is 300 nm. The black phosphorus heterojunction is a three-layer structure with black phosphorus nanosheets as the bottom layer, InSe as the middle layer and black phosphorus nanosheets as the top layer. The thickness of the black phosphorus nanosheets is 25 nm and the thickness of InSe is 20 nm.

[0036] Example 2 The method for preparing the black phosphorus heterojunction water-blocking and oxygen-barrier coating in this embodiment includes the following steps: 1) Mix 50 mL of chloroform and 50 mL of LDMF evenly, add 500 mg of block BP, and sonicate for 2 h after passing argon gas for 30 min. Collect the supernatant by centrifugation and dry it under vacuum at 60 °C for 12 h to obtain BP nanosheets. 27 mg of BP nanosheets were dispersed in a mixture containing 160 mL of ethanol, 240 mL of water and 1.2 g of SDBS. 60 µL of ammonium hydroxide solution, 750 µL of HCHO solution and 3 mL of 0.2 M NiCl2 solution were added under stirring. After purging with nitrogen for 1 h, the temperature was raised to 40 °C and reacted for 1 h. The solid was collected by centrifugation and washed three times with ethanol to obtain the base material. 2) After the base material is naturally dried, it is placed in a sealed container containing silicone oil and heated to 130℃ for 20 min. Then, it is transferred to 50 mL of chloroform solution containing 0.5 g of 1,12-dodecaneamine and reacted at 80℃ for 15 min. After the reaction is completed, the sample is taken out and soaked in 50℃ warm acetone for 1 h to remove unreacted 1,12-dodecaneamine. After drying with nitrogen, the barrier material is obtained. 3) Dissolve 0.8g of PVA powder in 92mL of deionized water at 90℃ and stir for 4h until completely transparent. Cool to room temperature, then slowly add 10mL of ethanol solution containing 0.5g of PDMAEMA. After uniform dispersion, add the barrier material and 0.15mL of 25% glutaraldehyde solution, followed by 0.5mL of 1M HCl. Continue stirring for 1h to obtain a spin-coating solution for a gel film. Then, spin-coate the gel film solution evenly onto the substrate surface and cure it at 60℃ to obtain a gel film. Then, transfer the entire solution to 0.1M sodium bicarbonate buffer solution to dissolve the gel film. At this point, the barrier material binds to the substrate surface to form a coating.

[0037] The coating thickness in this embodiment is 25 nm.

[0038] The substrate of this embodiment includes a substrate and a black phosphorus heterojunction disposed on the substrate. The substrate includes a silicon layer and a silicon dioxide layer. The thickness of the silicon layer is 300 μm and the thickness of the silicon dioxide layer is 200 nm. The black phosphorus heterojunction is a three-layer structure with black phosphorus nanosheets as the bottom layer, InSe as the middle layer and black phosphorus nanosheets as the top layer. The thickness of the black phosphorus nanosheets is 25 nm and the thickness of InSe is 20 nm.

[0039] Example 3 The method for preparing the black phosphorus heterojunction water-blocking and oxygen-barrier coating in this embodiment includes the following steps: 1) Mix 50 mL of chloroform and 50 mL of LDMF evenly, add 500 mg of block BP, and sonicate for 2 h after passing argon gas for 30 min. Collect the supernatant by centrifugation and dry it under vacuum at 60 °C for 12 h to obtain BP nanosheets. 27 mg of BP nanosheets were dispersed in a mixture containing 160 mL of ethanol, 240 mL of water and 1.2 g of SDBS. 60 µL of ammonium hydroxide solution, 750 µL of HCHO solution and 3 mL of 0.05 M NiCl2 solution were added under stirring. After purging with nitrogen for 1 h, the temperature was raised to 80 °C and reacted for 3 h. The solid was collected by centrifugation and washed three times with ethanol to obtain the base material. 2) After the base material is naturally dried, it is placed in a sealed container containing silicone oil and heated to 130℃ for 20 min. Then, it is transferred to 50 mL of chloroform solution containing 0.5 g of 1,12-dodecaneamine and reacted at 120℃ for 45 min. After the reaction is completed, the sample is taken out and soaked in 50℃ warm acetone for 1 h to remove unreacted 1,12-dodecaneamine. After drying with nitrogen, the barrier material is obtained. 3) Dissolve 0.8g of PVA powder in 92mL of deionized water at 90℃ and stir for 4h until completely transparent. Cool to room temperature, then slowly add 10mL of ethanol solution containing 0.5g of PDMAEMA. After uniform dispersion, add the barrier material and 0.15mL of 25% glutaraldehyde solution, followed by 0.5mL of 1M HCl. Continue stirring for 1h to obtain a spin-coating solution for a gel film. Then, spin-coate the gel film solution evenly onto the substrate surface and cure it at 60℃ to obtain a gel film. Then, transfer the entire solution to 0.1M sodium bicarbonate buffer solution to dissolve the gel film. At this point, the barrier material binds to the substrate surface to form a coating.

[0040] The coating thickness in this embodiment is 25 nm.

[0041] The substrate of this embodiment includes a substrate and a black phosphorus heterojunction disposed on the substrate. The substrate includes a silicon layer and a silicon dioxide layer. The thickness of the silicon layer is 500 μm and the thickness of the silicon dioxide layer is 400 nm. The black phosphorus heterojunction is a three-layer structure with black phosphorus nanosheets as the bottom layer, InSe as the middle layer and black phosphorus nanosheets as the top layer. The thickness of the black phosphorus nanosheets is 25 nm and the thickness of InSe is 20 nm.

[0042] Control group 1 The preparation method of the black phosphorus heterojunction water-blocking and oxygen-barrier coating in this control group includes the following steps: 1) Mix 50 mL of chloroform and 50 mL of LDMF evenly, add 500 mg of block BP, and sonicate for 2 h after passing argon gas for 30 min. Collect the supernatant by centrifugation and dry it under vacuum at 60 °C for 12 h to obtain BP nanosheets. 27 mg of BP nanosheets were dispersed in a mixture containing 160 mL of ethanol, 240 mL of water and 1.2 g of SDBS. 60 µL of ammonium hydroxide solution, 750 µL of HCHO solution and 3 mL of 0.1 M NiCl2 solution were added under stirring. After purging with nitrogen for 1 h, the temperature was raised to 60 °C and reacted for 2 h. The solid was collected by centrifugation and washed three times with ethanol to obtain the barrier material. 2) Dissolve 0.8g of PVA powder in 92mL of deionized water at 90℃ and stir for 4h until completely transparent. Cool to room temperature, then slowly add 10mL of ethanol solution containing 0.5g of PDMAEMA. After uniform dispersion, add the barrier material and 0.15mL of 25% glutaraldehyde solution, followed by 0.5mL of 1M HCl. Continue stirring for 1h to obtain a spin-coating solution for a gel film. Then, spin-coate the gel film solution evenly onto the substrate surface and cure it at 60℃ to obtain a gel film. Then, transfer the entire solution to 0.1M sodium bicarbonate buffer solution to dissolve the gel film. At this point, the barrier material binds to the substrate surface to form a coating.

[0043] The coating thickness in this control group was 25 nm.

[0044] The substrate of this control group includes a substrate and a black phosphorus heterojunction disposed on the substrate. The substrate includes a silicon layer and a silicon dioxide layer. The thickness of the silicon layer is 400 μm and the thickness of the silicon dioxide layer is 300 nm. The black phosphorus heterojunction is a three-layer structure with black phosphorus nanosheets as the bottom layer, InSe as the middle layer and black phosphorus nanosheets as the top layer. The thickness of the black phosphorus nanosheets is 25 nm and the thickness of InSe is 20 nm.

[0045] Control group 2 The preparation method of the black phosphorus heterojunction water-blocking and oxygen-barrier coating in this control group includes the following steps: 1) Mix 50 mL of chloroform and 50 mL of LDMF evenly, add 500 mg of block BP, and sonicate for 2 h after passing argon gas for 30 min. Collect the supernatant by centrifugation and dry it under vacuum at 60 °C for 12 h to obtain BP nanosheets. 2) After the BP nanosheets were naturally dried, they were placed in a sealed container containing silicone oil and heated to 130℃ for 20 min. Then, they were transferred to 50 mL of chloroform solution containing 0.5 g of 1,12-dodecaneamine and reacted at 100℃ for 30 min. After the reaction was completed, the sample was taken out and soaked in 50℃ warm acetone for 1 h to remove unreacted 1,12-dodecaneamine. After drying with nitrogen, the barrier material was obtained. 3) Dissolve 0.8g of PVA powder in 92mL of deionized water at 90℃ and stir for 4h until completely transparent. Cool to room temperature, then slowly add 10mL of ethanol solution containing 0.5g of PDMAEMA. After uniform dispersion, add the barrier material and 0.15mL of 25% glutaraldehyde solution, followed by 0.5mL of 1M HCl. Continue stirring for 1h to obtain a spin-coating solution for a gel film. Then, spin-coate the gel film solution evenly onto the substrate surface and cure it at 60℃ to obtain a gel film. Then, transfer the entire solution to 0.1M sodium bicarbonate buffer solution to dissolve the gel film. At this point, the barrier material binds to the substrate surface to form a coating.

[0046] The coating thickness in this control group was 25 nm.

[0047] The substrate of this control group includes a substrate and a black phosphorus heterojunction disposed on the substrate. The substrate includes a silicon layer and a silicon dioxide layer. The thickness of the silicon layer is 400 μm and the thickness of the silicon dioxide layer is 300 nm. The black phosphorus heterojunction is a three-layer structure with black phosphorus nanosheets as the bottom layer, InSe as the middle layer and black phosphorus nanosheets as the top layer. The thickness of the black phosphorus nanosheets is 25 nm and the thickness of InSe is 20 nm.

[0048] Performance testing PMMA was spin-coated onto the coating surfaces of Examples 1-3 and Control Groups 1-2, followed by baking at 60°C for 5 minutes and electron beam exposure. Specific electrode patterns were then obtained through a development process. Under the premise of controlling the substrate temperature at 100°C, a 4nm thick chromium layer and a 40nm thick gold layer were successively deposited at 1300°C to form the source and drain electrodes. The samples were then immersed in acetone at 40°C for 20 minutes, removed, and rapidly dried with high-purity nitrogen to obtain the infrared detector for testing.

[0049] 1. Photoresponse Performance Testing: The photoelectric performance of the prepared infrared detector was characterized using a system coupled with a low-temperature probe station and a semiconductor parameter analyzer. During testing, a 1064nm laser with a power of 50mW / cm² was used as the light source and vertically irradiated the infrared detector to obtain the device's V0. ds -I ds The correspondence. 2. Stability Test: The infrared detector prepared above was placed in an environment with a temperature of 25℃ and a relative humidity of 50% for 360 hours of continuous aging. Subsequently, the light response test system described above was used again to measure the I after aging under the same conditions. ds By calculating I after aging ds With initial I ds The ratio of I to I ds Retention rate is used as an indicator to evaluate the stability performance of a device.

[0050] Analysis of Examples 1-3 and Control Groups 1-2 and in combinationFigure 1 and Figure 2 The test data shows that the coating prepared in this application can significantly improve the infrared detection performance and stability of the infrared detector. Compared with Examples 1-3, although the infrared detector corresponding to Control Group 1 has similar initial photoelectric performance, it shows significant improvement after aging. ds The significantly reduced retention rate indicates that the surface of the black phosphorus heterojunction lacks an effective protective layer, making it more susceptible to oxidative degradation when exposed to a humid and hot environment for extended periods, leading to faster performance decline. Compared to Examples 1-3, the coating composition of Control Group 2 does not contain loaded Ni nanoparticles, resulting in a decrease in corresponding infrared detection performance. This suggests that while Ni nanoparticles play a positive role in infrared detection performance, their absence affects the final performance of the detector.

[0051] Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A method for preparing a black phosphorus heterojunction water-blocking and oxygen-barrier coating, characterized in that, Includes the following steps: 1) Mix chloroform and DMF evenly, add lumpy BP and sonicate, collect the supernatant by centrifugation, and vacuum dry to obtain BP nanosheets; disperse BP nanosheets in a mixture containing ethanol, water and SDBS, add ammonium hydroxide, HCHO and NiCl2 under stirring and heat to react, collect the solid by centrifugation and wash with ethanol to obtain the base material; 2) After the base material is naturally dried, it is placed in a sealed container containing silicone oil and heated; then, it is transferred to chloroform containing 1,12-dodecaneamine for reaction; after the reaction is completed, it is transferred to acetone for immersion, and then removed and dried with nitrogen to obtain the barrier material. 3) A coating is obtained by transferring the barrier material to the substrate surface through a condensation process.

2. The method for preparing the black phosphorus heterojunction water-blocking and oxygen-barrier coating according to claim 1, characterized in that: The condensate membrane is made of a material comprising the following components: polyvinyl alcohol, PDMAEMA, and water.

3. The method for preparing the black phosphorus heterojunction water-blocking and oxygen-barrier coating according to claim 1, characterized in that: In step 1), the temperature of the heating reaction is 40-80℃, and the reaction time is 1-3h.

4. The method for preparing the black phosphorus heterojunction water-blocking and oxygen-barrier coating according to claim 1, characterized in that: In step 2), the reaction temperature is 80-120℃ and the reaction time is 15-45min.

5. The method for preparing the black phosphorus heterojunction water-blocking and oxygen-barrier coating according to claim 1, characterized in that: The NiCl2 is an aqueous solution with a concentration of 0.05-0.2M.

6. The method for preparing the black phosphorus heterojunction water-blocking and oxygen-barrier coating according to claim 1, characterized in that: The substrate includes a substrate and a black phosphorus heterojunction disposed on the substrate.

7. The method for preparing the black phosphorus heterojunction water-blocking and oxygen-barrier coating according to claim 6, characterized in that: The substrate includes a silicon layer and a silicon dioxide layer disposed on the silicon layer.

8. The method for preparing the black phosphorus heterojunction water-blocking and oxygen-barrier coating according to claim 7, characterized in that: The thickness of the silicon layer is 300-500 μm.

9. The method for preparing the black phosphorus heterojunction water-blocking and oxygen-barrier coating according to claim 7, characterized in that: The thickness of the silicon dioxide layer is 200-400 nm.

10. A black phosphorus heterojunction water-blocking and oxygen-barrier coating, characterized in that: It is prepared by any one of the preparation methods described in claims 1-9.

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