Purple phosphorus / patterned graphene composite multifunctional sensor and preparation method and application thereof
By preparing purple phosphorus/patterned graphene composite structures using wet etching and laser ablation, the problems of complex fabrication and insufficient sensitivity of traditional graphene sensors are solved, enabling efficient detection by multifunctional sensors.
Patent Information
- Application Number
- CN202511909274.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-17
- Publication Date
- 2026-03-20
AI Technical Summary
Existing graphene sensors suffer from complex fabrication processes, poor signal consistency, and insufficient multimodal decoupling capabilities, making it difficult to achieve high-sensitivity detection of multiple physical mechanisms.
Patterned graphene arrays were prepared by a combination of wet etching and transfer with laser ablation, and purple phosphorus nanosheets were prepared by laser liquid phase exfoliation to form a purple phosphorus/patterned graphene composite structure. Silver wire electrodes were then set to complete the device integration.
The fabrication process was simplified, the electrical signal response capability of the sensor and the sensitivity of multiple signal detection were improved, and high-performance detection of temperature, humidity, strain and gas concentration was achieved.
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Figure CN121703205A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application belongs to the technical field of sensors, and particularly relates to a purple phosphor / patterned graphene composite multifunctional sensor and a preparation method and application thereof. BACKGROUND
[0002] In the field of wearable and flexible sensing technology, graphene has become the core conductive base material of multifunctional sensors due to its high carrier mobility, excellent mechanical flexibility and good environmental stability. The current mainstream solutions include: using photolithography-transferring-chemical modification process to construct patterned graphene array; improving gas sensitive / temperature sensitive response capability by wet loading of metal oxides (such as SnO2, ZnO) or carbon nanomaterials (such as CNTs, rGO); introducing functional materials onto the surface of graphene by spin coating, spraying or drop coating, and then forming a composite structure through annealing or drying treatment; some studies attempt to use conductive polymers such as polyaniline and PEDOT:PSS for interface modification to enhance the recognition sensitivity to humidity or strain. The above methods have achieved the improvement of single mode sensing performance at the laboratory level, and have completed preliminary integration in some flexible electronic skins, with certain engineering basis.
[0003] However, the existing technology still has obvious limitations: first, the traditional photolithography-transferring process has many steps, requires mask preparation, plasma etching and organic solvent cleaning, has strong equipment dependence, and has a long single piece preparation period (>8 hours), which is difficult to meet the needs of large-scale production; second, the conventional wet loading method easily causes uneven coverage, edge accumulation and large interface contact resistance of graphene film, resulting in poor signal consistency between different pattern areas (relative standard deviation RSD>12%); third, the functional materials used are mostly inorganic nanoparticles or organic molecular modification layers, which are difficult to consider gas adsorption, water molecule polarization, thermal expansion response and stress transmission and other physical mechanisms on the same device, and there is serious signal crosstalk between different sensing modes; fourth, there is a lack of design ideas for the synergistic matching of specific pattern geometric features and functional materials, and the quantitative relationship between "pattern size-sensing response-interface energy band modulation" has not been established, resulting in insufficient multi-mode decoupling capability and inability to realize spatial coding independent detection. SUMMARY
[0004] In order to overcome the shortcomings of the above-mentioned prior art, the purpose of the present application is to provide a purple phosphor / patterned graphene composite multifunctional sensor and a preparation method and application thereof, to solve the technical problems of single function, complex preparation and insufficient sensitivity of traditional sensors.
[0005] In order to achieve the above-mentioned purpose, the technical scheme adopted by the present application is as follows: In a first aspect, the present application provides a preparation method of a purple phosphor / patterned graphene composite multifunctional sensor, comprising the following steps: Step 1, etching the graphene-loaded copper foil sample in an etching solution, and transferring the obtained graphene film to a substrate surface after the copper foil is completely removed; Step 2, treating the graphene film on the substrate by a laser ablation method to form a micron-sized patterned graphene array on the surface thereof; Step 3, treating bulk purple phosphorus by a laser liquid phase exfoliation method to obtain a purple phosphorus nanosheet dispersion; Step 4, coating the obtained purple phosphorus nanosheet dispersion to the surface of the patterned graphene array to make the purple phosphorus nanosheet composite with the patterned graphene to form a purple phosphorus / patterned graphene composite sensitive structure; Step 5, arranging electrodes at both ends of the obtained composite sensitive structure to prepare the purple phosphorus / patterned graphene composite multifunctional sensor.
[0006] The further improvement of the present application lies in that, in Step 1, the etching solution is a mixed solution of ferric chloride and hydrochloric acid.
[0007] The further improvement of the present application lies in that, in Step 2, the laser used in the laser ablation method is a nanosecond laser, a picosecond laser or a femtosecond laser; and the shape of the patterned graphene array is a circle, a square, a triangle or a hexagon.
[0008] The further improvement of the present application lies in that, in Step 3, the laser liquid phase exfoliation method specifically comprises: grinding the bulk purple phosphorus crystal and dispersing it in ethanol to configure a dispersion with a concentration of 0.5-1 mg / mL, and then performing laser irradiation treatment.
[0009] The further improvement of the present application lies in that, in Step 4, the coating method is a spin coating method; and the spin coating method comprises three stages: firstly rotating at a speed of 180-300 r / min for 0.5-1 min, then rotating at a speed of 1000-1500 r / min for 3-5 min, and finally rotating at a speed of 2000-3000 r / min for 0.5-1 min.
[0010] The further improvement of the present application lies in that, in Step 1, the substrate is a flexible substrate, specifically polydimethylsiloxane or polyether sulfone.
[0011] The further improvement of the present application lies in that, in Step 1, the substrate is a rigid substrate, specifically Si / SiO2 or glass.
[0012] The further improvement of the present application lies in that, in Step 5, the electrode is a silver wire electrode.
[0013] In a second aspect, the present application also provides a purple phosphorus / patterned graphene composite multifunctional sensor, which is prepared by the above-mentioned preparation method; the sensor comprises a substrate, a patterned graphene array formed on the substrate, purple phosphorus nanosheets composited on the surface of the patterned graphene array, and electrodes connected to both ends of the composite sensitive structure.
[0014] In a third aspect, the present application also provides an application of the above-mentioned purple phosphorus / patterned graphene composite multifunctional sensor, which is used for detecting at least one parameter of temperature, humidity, strain or gas concentration; the gas includes CO, NH3, NO2, H2O, NO, N 2、 O2, CO2, H2, SO2 or H2S.
[0015] Compared with the prior art, the present application has the following beneficial effects: The present application provides a preparation method of a purple phosphorus / patterned graphene composite multifunctional sensor, which firstly attaches a graphene film on a substrate stably through wet etching and transfer, ensuring the integrity and reliability of the core conductive layer of the sensor. Subsequently, a micron-level pattern array is precisely processed on the surface of the graphene by using laser ablation technology, which not only gives the graphene film a specific structure, but more importantly, effectively regulates the characteristics of the conductive network through patterning design, thereby directly enhancing the electrical signal response capability of the sensor under stress. Purple phosphorus nanosheets are prepared by using laser liquid phase exfoliation method, obtaining a high-activity thin-layer material, which provides abundant sites for adsorbing gas or water molecules due to its large specific surface area. After the purple phosphorus nanosheets are coated on the patterned graphene, the composite structure formed by the two plays a synergistic effect: the patterned graphene serves as an efficient electron conduction path, while the purple phosphorus nanosheets serve as a sensitive recognition unit, which together improves the detection sensitivity of the device to physical and chemical changes in the environment. Finally, the device integration is completed by setting electrodes, and the prepared sensor not only maintains the simple and reliable preparation process, but also realizes high-performance detection of multiple signals. BRIEF DESCRIPTION OF DRAWINGS
[0016] The drawings described herein are for illustrative purposes only and are not intended to limit the scope of the present application in any way. In addition, the shapes and scale sizes of the components in the drawings are only illustrative and are used to help understand the present application, and are not specific limitations on the shapes and scale sizes of the components.
[0017] Figure 1 The patterned graphene morphology of Example 1 of the present application; Figure 2 The strain sensing result of Example 1 of the present application; Figure 3 The gas sensing result of Example 2 of the present application; Figure 4Humidity sensing results for Example 3 of the present invention; Figure 5 Temperature sensing results for Example 4 of the present invention. DETAILED DESCRIPTION
[0018] To enable persons skilled in the art to understand the features and effects of the present invention, the following is a general description and definition of the terms and phrases mentioned in the specification and claims. Unless otherwise specified, all technical and scientific words used herein have the usual meanings understood by those skilled in the art of the present invention, and in the event of a conflict, the definitions in the specification shall prevail.
[0019] Theories or mechanisms described and disclosed herein, whether correct or not, should not be considered limiting of the scope of the present invention, which can be practiced without regard to any particular theory or mechanism.
[0020] Herein, all features defined by numerical ranges or percentage ranges, such as numerical values, amounts, contents and concentrations, are for the sake of brevity and convenience. Accordingly, the description of numerical ranges or percentage ranges should be considered to have encompassed and specifically disclosed all possible sub-ranges and individual numerical values within the range (including integers and fractions).
[0021] Herein, unless otherwise specified, "comprise", "include", "contain", "have" or similar words encompass the meaning of "consist of" and "consist essentially of", for example, "A comprises a" encompasses the meaning of "A comprises a and other" and "A comprises only a".
[0022] Herein, for the sake of brevity, all possible combinations of the technical features in each embodiment or example are not described. Therefore, as long as the combinations of the technical features do not contradict each other, the technical features in each embodiment or example can be combined arbitrarily, and all possible combinations should be considered as the scope of the present specification.
[0023] The present invention provides a method for preparing a purple phosphor / patterned graphene composite multifunctional sensor, comprising the following steps: Step 1, growing a graphene film on a copper foil by chemical vapor deposition (CVD) to obtain a graphene / copper foil sample; wherein the CVD growth parameters are as follows: CH4 flow rate is set to 5-15 mL / min, H2 flow rate is set to 40-60 mL / min, Ar flow rate is 250-350 mL / min, growth temperature is 1040-1080℃, and growth time is 10-20 min; the graphene / copper foil sample is immersed in an etching solution for etching, and after the copper foil is completely removed, the obtained graphene film is transferred to a substrate surface; wherein the etching solution is a mixed solution of ferric chloride and hydrochloric acid, the ferric chloride solution and the hydrochloric acid solution are mixed at a volume ratio of 1:1, and the concentration is 0.1-1 mol / L; the substrate is one or more of Si / SiO2, glass, organic filter membrane, polydimethylsiloxane (PDMS), or polyethersulfone (PES).
[0024] Step 2, treating the graphene film on the substrate using a laser ablation method to form a micron-scale patterned graphene array on its surface; the laser ablation method uses nanosecond laser, picosecond laser or femtosecond laser, wherein the laser wavelength is 256-1100 nm, the laser power is 1-100 W, the medium energy input is 70-90 J cm -2 , the scanning speed is 5-25 mm s -1 , the spot diameter is 40-60 µm, the repetition frequency is 1 K Hz, and the pulse width is 100 fs-300 ns; the shape of the patterned graphene array is circular, square, triangular or hexagonal, the side length of the square is 50-200 µm; the circular size is Φ50-100 µm; the triangle is an equilateral triangle with a side length of 50-100 µm; the hexagon has a side length of 50-150 µm, and the pattern spacing is 50-200 µm.
[0025] Step 3, treating bulk purple phosphorus using a laser liquid exfoliation method to obtain a purple phosphorus nanosheet dispersion, specifically: grinding bulk purple phosphorus crystals to obtain a large amount of purple phosphorus powder, then dispersing the ground purple phosphorus powder in ethanol to prepare a dispersion with a concentration of 0.5-1 mg / mL, and then performing laser irradiation treatment; the laser irradiation treatment parameters are as follows: spot diameter is 40-60 µm, repetition frequency is 100-200 K Hz, pulse width is 100 fs-300 ns; laser scanning speed is 100-1000 mm / s, and power is 1-30 W.
[0026] Step 4: The obtained purple phosphorus nanosheet dispersion is coated onto the surface of the patterned graphene array, so that the purple phosphorus nanosheets and patterned graphene are composite to form a purple phosphorus / patterned graphene composite sensitive structure. The coating method is spin coating, specifically: the patterned graphene array sample is placed on a spin coater, and the purple phosphorus nanosheet dispersion obtained in step 3 is dropped onto the surface of the patterned graphene array sample using a pipette. The spin coating method includes three stages: first, rotating at a speed of 180-300 r / min for 0.5-1 min, then rotating at a speed of 1000-1500 r / min for 3-5 min, and finally rotating at a speed of 2000-3000 r / min for 0.5-1 min.
[0027] Step 5: Set silver wires as electrodes at both ends of the obtained composite sensitive structure, and connect the electrodes to the detection circuit to obtain the purple phosphorus / patterned graphene composite multifunctional sensor.
[0028] The purple phosphorus / patterned graphene composite multifunctional sensor prepared by this invention can be tested using static and dynamic methods for gas sensitivity, thermometry using a thermostat, strain sensing using a tensile test, and humidity sensitivity using a saturated salt solution method. The test gas for gas sensitivity testing is CO, NH3, NO2, H2O, NO, N2, O2, CO2, H2, SO2, or H2S. The gas concentration is 0-1000 ppm. The thermosensitivity test measures the change in relative resistance of the sensor over time at a temperature of 30-50℃. The strain sensing test measures the change in resistance under 1-20% tensile strain conditions. The humidity sensing test measures the change in relative resistance and humidity coefficient at a humidity level of 10-95% RH.
[0029] The present invention will be further illustrated below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, it should be understood that after reading the teachings of this invention, those skilled in the art can make various alterations or modifications to the invention, and these equivalent forms also fall within the scope defined by the appended claims.
[0030] The following examples use instruments and equipment conventional in the art. Experimental methods in the following examples, unless otherwise specified, are generally performed under conventional conditions or as recommended by the manufacturer. All raw materials used in the following examples are conventional commercially available products with specifications conventional in the art. In this specification and the following examples, unless otherwise specified, "%" refers to weight percentage, "parts" refers to parts by weight, and "ratio" refers to weight proportion.
[0031] Example 1 This embodiment provides a method for fabricating a purple phosphorus / circular patterned graphene strain sensor, including the following steps: Step 1: Graphene films are prepared on copper foil using CVD to obtain graphene / copper foil samples. The specific CVD growth parameters are as follows: CH4 flow rate is set to 5 mL / min, H2 flow rate is set to 50 mL / min, Ar flow rate is set to 300 mL / min, growth temperature is 1040℃, and growth time is 10 min. The graphene / copper foil samples are then immersed in a mixed solution of ferric chloride and hydrochloric acid for etching. The ferric chloride solution and hydrochloric acid solution are mixed at a volume ratio of 1:1 and the concentration is 0.1 mol / L. After the copper foil is completely removed, the obtained graphene film is transferred to the surface of a Si / SiO2 substrate.
[0032] Step 2: Patterning of the graphene film is performed using a femtosecond laser with a wavelength of 1064 nm, a laser power of 30 W, and a scanning speed of 5 mm / s. -1 The spot diameter is 40 µm, the repetition frequency is 1 kHz, and the pulse width is 100 fs. The pattern array is circular with a size of Φ50 and a pattern spacing of 50 µm, as shown below. Figure 1 As shown.
[0033] Step 3: Grind the blocky purple phosphorus crystals to obtain a large amount of purple phosphorus powder. Then, disperse the ground purple phosphorus powder in ethanol to prepare a dispersion with a purple phosphorus concentration of 0.5 mg / mL. Then, perform laser irradiation treatment. The parameters of the laser irradiation treatment are: spot diameter of 40 µm, repetition frequency of 100 kHz, pulse width of 300 ns, laser scanning speed of 100 mm / s, and power of 1 W.
[0034] Step 4: Place the patterned graphene array sample on a spin coater, and use a pipette to drop the purple phosphorus nanosheet dispersion obtained in Step 3 onto the surface of the patterned graphene array sample, so that the purple phosphorus nanosheets and patterned graphene are combined to form a purple phosphorus / patterned graphene composite sensitive structure. The spin coating method includes three stages: first, spin at 180 r / min for 1 min; then spin at 1000 r / min for 5 min; and finally spin at 2000 r / min for 1 min.
[0035] Step 5: Silver wires are led out from both ends of the composite sensitive structure obtained in Step 4 as electrodes. Connecting these electrodes to the detection circuit yields a purple phosphorus / patterned graphene multifunctional sensor. The strain sensing was tested using a tensile test method, measuring the resistance change under tensile strain conditions of 1-20%. The strain sensing experimental results are shown below. Figure 2 .
[0036] Example 2 This embodiment provides a method for preparing a purple phosphorus / square patterned graphene gas sensor, including the following steps: Step 1: Graphene films were prepared on copper foil using CVD to obtain graphene / copper foil samples. The specific CVD growth parameters were as follows: CH4 flow rate was set to 8 mL / min, H2 flow rate was set to 60 mL / min, Ar flow rate was set to 350 mL / min, growth temperature was 1080℃, and growth time was 20 min. The graphene / copper foil samples were then immersed in a mixed solution of ferric chloride and hydrochloric acid for etching. The ferric chloride solution and hydrochloric acid solution were mixed at a volume ratio of 1:1 and the concentration was 1 mol / L. After the copper foil was completely removed, the obtained graphene film was transferred to the surface of a polydimethylsiloxane (PDMS) substrate.
[0037] Step 2: Patterning of the graphene film is performed using a nanosecond laser with a wavelength of 256 nm, a laser power of 10 W, and a scanning speed of 25 mm / s. -1 The spot diameter is 60 µm, the repetition frequency is 1 kHz, and the pulse width is 300 ns. The pattern array is square, with each square having a side length of 100 µm and a pattern spacing of 100 µm.
[0038] Step 3: Grind the blocky purple phosphorus crystals to obtain a large amount of purple phosphorus powder. Then, disperse the ground purple phosphorus powder in ethanol to prepare a dispersion with a purple phosphorus concentration of 1 mg / mL. Then, perform laser irradiation treatment. The parameters of the laser irradiation treatment are: spot diameter of 50 µm, repetition frequency of 200 kHz, pulse width of 300 ns, laser scanning speed of 1000 mm / s, and power of 30 W.
[0039] Step 4: Place the patterned graphene array sample on a spin coater, and use a pipette to drop the purple phosphorus nanosheet dispersion obtained in Step 3 onto the surface of the patterned graphene array sample, so that the purple phosphorus nanosheets and patterned graphene are combined to form a purple phosphorus / patterned graphene composite sensitive structure. The spin coating method includes three stages: first, spin at 300 r / min for 0.5 min; then spin at 1500 r / min for 3 min; and finally spin at 3000 r / min for 0.5 min.
[0040] Step 5: Silver wires are led out from both ends of the composite sensitive structure obtained in Step 4 as electrodes. Connecting these electrodes to the detection circuit yields a purple phosphorus patterned graphene multifunctional sensor. The test gases for gas sensing are 0-1000 ppm CO and NO. The gas sensing results are as follows: Figure 3 As shown.
[0041] Example 3 This embodiment provides a method for preparing a purple phosphorus / hexagonal patterned graphene humidity sensor, including the following steps: Step 1: Graphene films are prepared on copper foil using CVD to obtain graphene / copper foil samples. The specific CVD growth parameters are as follows: CH4 flow rate is set to 10 mL / min, H2 flow rate is set to 50 mL / min, Ar flow rate is set to 300 mL / min, growth temperature is 1060℃, and growth time is 15 min. The graphene / copper foil samples are then immersed in a mixed solution of ferric chloride and hydrochloric acid for etching. The ferric chloride solution and hydrochloric acid solution are mixed at a volume ratio of 1:1 and the concentration is 0.5 mol / L. After the copper foil is completely removed, the obtained graphene film is transferred to the surface of a glass substrate.
[0042] Step 2: Patterning the graphene film using a picosecond laser, with a laser wavelength of 532 nm, a laser power of 50 W, and a scanning speed of 10 mm / s. -1 The spot diameter is 50 µm, the repetition frequency is 1 kHz, and the pulse width is 180 ps. The pattern array is hexagonal, with a side length of 100 µm and a pattern spacing of 200 µm.
[0043] Step 3: Grind the blocky purple phosphorus crystals to obtain a large amount of purple phosphorus powder. Then, disperse the ground purple phosphorus powder in ethanol to prepare a dispersion with a purple phosphorus concentration of 0.75 mg / mL. Then, perform laser irradiation treatment. The parameters of the laser irradiation treatment are: spot diameter of 50 µm, repetition frequency of 150 kHz, pulse width of 150 ns, laser scanning speed of 500 mm / s, and power of 25 W.
[0044] Step 4: Place the patterned graphene array sample on a spin coater, and use a pipette to drop the purple phosphorus nanosheet dispersion obtained in Step 3 onto the surface of the patterned graphene array sample, so that the purple phosphorus nanosheets and patterned graphene are combined to form a purple phosphorus / patterned graphene composite sensitive structure. The spin coating method includes three stages: first, spin at 200 r / min for 0.5 min; then spin at 1200 r / min for 4 min; and finally spin at 2500 r / min for 1 min.
[0045] Step 5: Silver wires are led out from both ends of the composite sensitive structure obtained in Step 4 as electrodes. Connecting these electrodes to the detection circuit yields a purple phosphorus patterned graphene multifunctional sensor. The humidity sensitivity is tested using the saturated salt solution method. The humidity sensitivity test measures the change in relative resistance and humidity coefficient at humidity levels of 10-95% RH. The results are shown in […]. Figure 4 .
[0046] Example 4 This embodiment provides a method for preparing a purple phosphorus / triangular patterned graphene temperature sensor, including the following steps: Step 1: Graphene films were prepared on copper foil using CVD to obtain graphene / copper foil samples. The specific CVD growth parameters were as follows: CH4 flow rate was set to 8 mL / min, H2 flow rate was set to 60 mL / min, Ar flow rate was set to 300 mL / min, growth temperature was 1060℃, and growth time was 10 min. The graphene / copper foil samples were then immersed in a mixed solution of ferric chloride and hydrochloric acid for etching. The ferric chloride solution and hydrochloric acid solution were mixed at a volume ratio of 1:1 and the concentration was 1 mol / L. After the copper foil was completely removed, the obtained graphene film was transferred to the surface of an organic filter membrane substrate.
[0047] Step 2: Patterning the graphene film using a femtosecond laser with a wavelength of 1100 nm, a laser power of 100 W, and a scanning speed of 10 mm / s. -1 The spot diameter is 50 µm, the repetition frequency is 1 kHz, and the pulse width is 100 fs. The pattern array is a triangle, the triangles are equilateral triangles with a side length of 100 µm, and the pattern spacing is 100 µm.
[0048] Step 3: Grind the blocky purple phosphorus crystals to obtain a large amount of purple phosphorus powder. Then, disperse the ground purple phosphorus powder in ethanol to prepare a dispersion with a purple phosphorus concentration of 1 mg / mL. Then, perform laser irradiation treatment. The parameters of the laser irradiation treatment are: spot diameter of 45 µm, repetition frequency of 200 kHz, pulse width of 100 ns, laser scanning speed of 800 mm / s, and power of 20 W.
[0049] Step 4: Place the patterned graphene array sample on a spin coater, and use a pipette to drop the purple phosphorus nanosheet dispersion obtained in Step 3 onto the surface of the patterned graphene array sample, so that the purple phosphorus nanosheets and patterned graphene are combined to form a purple phosphorus / patterned graphene composite sensitive structure. The spin coating method includes three stages: first, spin at 200 r / min for 0.5 min; then spin at 1200 r / min for 4 min; and finally spin at 3000 r / min for 0.5 min.
[0050] Step 5: Silver wires are led out from both ends of the composite sensitive structure obtained in Step 4 as electrodes. Connecting these electrodes to the detection circuit yields a purple phosphorus patterned graphene multifunctional sensor. Thermosensitive properties are tested using a thermostat method, with the test temperature being 30-50℃, measuring the change in relative resistance of the sensor over time. The thermosensitive sensing results are as follows: Figure 5 As shown.
[0051] Example 5 This embodiment provides a method for fabricating a purple phosphorus / square patterned graphene strain sensor, including the following steps: Step 1: Graphene films were prepared on copper foil using CVD to obtain graphene / copper foil samples. The specific CVD growth parameters were as follows: CH4 flow rate was set to 10 mL / min, H2 flow rate was set to 60 mL / min, Ar flow rate was set to 350 mL / min, growth temperature was 1060℃, and growth time was 10 min. The graphene / copper foil samples were then immersed in a mixed solution of ferric chloride and hydrochloric acid for etching. The ferric chloride solution and hydrochloric acid solution were mixed at a volume ratio of 1:1 and the concentration was 1 mol / L. After the copper foil was completely removed, the obtained graphene film was transferred to the surface of a polyethersulfone (PES) substrate.
[0052] Step 2: Patterning the graphene film using a nanosecond laser with a wavelength of 1064 nm, a laser power of 100 W, and a scanning speed of 25 mm / s. -1 The spot diameter is 40 µm, the repetition frequency is 1 kHz, and the pulse width is 100 ns. The pattern array is square, with each square having a side length of 200 µm and a pattern spacing of 200 µm.
[0053] Step 3: Grind the blocky purple phosphorus crystals to obtain a large amount of purple phosphorus powder. Then, disperse the ground purple phosphorus powder in ethanol to prepare a dispersion with a purple phosphorus concentration of 0.75 mg / mL. Then, perform laser irradiation treatment. The parameters of the laser irradiation treatment are: spot diameter of 60 µm, repetition frequency of 150 kHz, pulse width of 800 fs, laser scanning speed of 1000 mm / s, and power of 30 W.
[0054] Step 4: Place the patterned graphene array sample on a spin coater, and use a pipette to drop the purple phosphorus nanosheet dispersion obtained in Step 3 onto the surface of the patterned graphene array sample, so that the purple phosphorus nanosheets and patterned graphene are combined to form a purple phosphorus / patterned graphene composite sensitive structure. The spin coating method includes three stages: first, spin at 200 r / min for 0.8 min; then spin at 1500 r / min for 5 min; and finally spin at 2000 r / min for 1 min.
[0055] Step 5: Silver wires are led out from both ends of the composite sensitive structure obtained in Step 4 as electrodes. Connecting these electrodes to the detection circuit yields a purple phosphorus patterned graphene multifunctional sensor. The strain sensing is tested using a tensile test method, measuring the resistance change under tensile strain conditions of 1-20%. The resistance change rate is 280%, and the sensitivity is 521.
[0056] Example 6 This embodiment provides a method for preparing a purple phosphorus / triangular patterned graphene gas sensor, including the following steps: Step 1: Graphene films were prepared on copper foil using CVD to obtain graphene / copper foil samples. The specific CVD growth parameters were as follows: CH4 flow rate was set to 10 mL / min, H2 flow rate was set to 50 mL / min, Ar flow rate was set to 300 mL / min, growth temperature was 1040℃, and growth time was 15 min. The graphene / copper foil samples were then immersed in a mixed solution of ferric chloride and hydrochloric acid for etching. The ferric chloride solution and hydrochloric acid solution were mixed at a volume ratio of 1:1 and the concentration was 0.5 mol / L. After the copper foil was completely removed, the obtained graphene film was transferred to the surface of a polydimethylsiloxane (PDMS) substrate.
[0057] Step 2: Patterning the graphene film using a picosecond laser, with a laser wavelength of 256 nm, a laser power of 50 W, and a scanning speed of 5 mm / s. -1 The spot diameter is 60 µm, the repetition frequency is 1 kHz, and the pulse width is 100 ps. The pattern array is a triangular array, the triangles are equilateral triangles with a side length of 50 µm, and the pattern spacing is 100 µm.
[0058] Step 3: Grind the blocky purple phosphorus crystals to obtain a large amount of purple phosphorus powder. Then, disperse the ground purple phosphorus powder in ethanol to prepare a dispersion with a purple phosphorus concentration of 0.5 mg / mL. Then, perform laser irradiation treatment. The parameters of the laser irradiation treatment are: spot diameter of 50 µm, repetition frequency of 150 kHz, pulse width of 100 ps, laser scanning speed of 100 mm / s, and power of 30 W.
[0059] Step 4: Place the patterned graphene array sample on a spin coater, and use a pipette to drop the purple phosphorus nanosheet dispersion obtained in Step 3 onto the surface of the patterned graphene array sample, so that the purple phosphorus nanosheets and patterned graphene are combined to form a purple phosphorus / patterned graphene composite sensitive structure. The spin coating method includes three stages: first, spin at 300 r / min for 0.5 min; then spin at 1000 r / min for 5 min; and finally spin at 2000 r / min for 1 min.
[0060] Step 5: Silver wires are led out from both ends of the composite sensitive structure obtained in Step 4 as electrodes. Connecting the electrodes to the detection circuit yields a purple phosphorus patterned graphene multifunctional sensor. Static and dynamic methods were used to test the gas sensitivity. The test gases were NH3, NO2, H2O, and N2. The gas concentrations ranged from 1 ppb to 500 ppm. The results showed that the selectivity for NO2 was optimal.
[0061] Example 7 This embodiment provides a method for preparing a purple phosphorus / hexagonal patterned graphene temperature sensor, including the following steps: Step 1: Graphene films are prepared on copper foil using CVD to obtain graphene / copper foil samples. The specific CVD growth parameters are as follows: CH4 flow rate is set to 15 mL / min, H2 flow rate is set to 60 mL / min, Ar flow rate is set to 350 mL / min, growth temperature is 1080℃, and growth time is 20 min. The graphene / copper foil samples are then immersed in a mixed solution of ferric chloride and hydrochloric acid for etching. The ferric chloride solution and hydrochloric acid solution are mixed at a volume ratio of 1:1 and the concentration is 1 mol / L. After the copper foil is completely removed, the obtained graphene film is transferred to the surface of a Si / SiO2 substrate.
[0062] Step 2: Patterning the graphene film using a femtosecond laser with a wavelength of 1100 nm, a laser power of 100 W, and a scanning speed of 25 mm / s. -1 The spot diameter is 60 µm, the repetition frequency is 1 kHz, and the pulse width is 100 fs. The pattern array is hexagonal, with a side length of 150 µm. The pattern spacing is 200 µm.
[0063] Step 3: Grind the blocky purple phosphorus crystals to obtain a large amount of purple phosphorus powder. Then, disperse the ground purple phosphorus powder in ethanol to prepare a dispersion with a purple phosphorus concentration of 0.75 mg / mL. Then, perform laser irradiation treatment. The parameters of the laser irradiation treatment are: spot diameter of 50 µm, repetition frequency of 180 kHz, pulse width of 500 fs, laser scanning speed of 500 mm / s, and power of 20 W.
[0064] Step 4: Place the patterned graphene array sample on a spin coater, and use a pipette to drop the purple phosphorus nanosheet dispersion obtained in Step 3 onto the surface of the patterned graphene array sample, so that the purple phosphorus nanosheets and patterned graphene are combined to form a purple phosphorus / patterned graphene composite sensitive structure. The spin coating method includes three stages: first, spin at 220 r / min for 1 min; then spin at 1300 r / min for 4 min; and finally spin at 2800 r / min for 0.5 min.
[0065] Step 5: Silver wires are led out from both ends of the composite sensitive structure obtained in Step 4 as electrodes. Connecting these electrodes to the detection circuit yields a purple phosphorus patterned graphene multifunctional sensor. Thermosensitive properties are tested using a thermostat method, with the test temperature being 30-50℃, measuring the change in relative resistance of the sensor over time. The resistance change rate is 58%, and the sensitivity is 140.
[0066] Example 8 This embodiment provides a method for preparing a purple phosphorus / circular patterned graphene humidity sensor, including the following steps: Step 1: Graphene films were prepared on copper foil using CVD to obtain graphene / copper foil samples. The specific CVD growth parameters were as follows: CH4 flow rate was set to 10 mL / min, H2 flow rate was set to 50 mL / min, Ar flow rate was set to 250 mL / min, growth temperature was 1040℃, and growth time was 10 min. The graphene / copper foil samples were then immersed in a mixed solution of ferric chloride and hydrochloric acid for etching. The ferric chloride solution and hydrochloric acid solution were mixed at a volume ratio of 1:1 and the concentration was 0.6 mol / L. After the copper foil was completely removed, the resulting graphene film was transferred to the surface of a glass substrate.
[0067] Step 2: Patterning the graphene film using a nanosecond laser with a wavelength of 532 nm, a power of 80 W, and a scanning speed of 20 mm / s. -1 The spot diameter is 45 µm, the repetition frequency is 1 kHz, and the pulse width is 50 ns. The pattern array is circular with a circle size of 80 µm and a pattern spacing of 80 µm.
[0068] Step 3: Grind the blocky purple phosphorus crystals to obtain a large amount of purple phosphorus powder. Then, disperse the ground purple phosphorus powder in ethanol to prepare a dispersion with a purple phosphorus concentration of 0.6 mg / mL. Then, perform laser irradiation treatment. The parameters of the laser irradiation treatment are: spot diameter of 50 µm, repetition frequency of 160 kHz, pulse width of 100 ns, laser scanning speed of 600 mm / s, and power of 20 W.
[0069] Step 4: Place the patterned graphene array sample on a spin coater, and use a pipette to drop the purple phosphorus nanosheet dispersion obtained in Step 3 onto the surface of the patterned graphene array sample, so that the purple phosphorus nanosheets and patterned graphene are combined to form a purple phosphorus / patterned graphene composite sensitive structure. The spin coating method includes three stages: first, spin at 200 r / min for 0.8 min; then spin at 1300 r / min for 3 min; and finally spin at 2600 r / min for 0.5 min.
[0070] Step 5: Silver wires are led out from both ends of the composite sensitive structure obtained in Step 4 as electrodes. Connecting the electrodes to the detection circuit yields a purple phosphorus patterned graphene multifunctional sensor. The humidity sensitivity is tested using a saturated salt solution method, measuring the relative resistance and humidity coefficient at 10-95% RH. The resistance change rate is 60%, and the sensitivity is 132.
[0071] Example 9 This embodiment provides a method for preparing a purple phosphorus / triangular patterned graphene gas sensor, including the following steps: Step 1: Graphene films were prepared on copper foil using CVD to obtain graphene / copper foil samples. The specific CVD growth parameters were as follows: CH4 flow rate was set to 10 mL / min, H2 flow rate was set to 60 mL / min, Ar flow rate was set to 300 mL / min, growth temperature was 1060℃, and growth time was 15 min. The graphene / copper foil samples were then immersed in a mixed solution of ferric chloride and hydrochloric acid for etching. The ferric chloride solution and hydrochloric acid solution were mixed at a volume ratio of 1:1 and the concentration was 0.2 mol / L. After the copper foil was completely removed, the obtained graphene film was transferred to the surface of a polydimethylsiloxane (PDMS) substrate.
[0072] Step 2: Patterning the graphene film using a picosecond laser with a wavelength of 1100 nm, a power of 100 W, and a scanning speed of 10 mm / s. -1 The spot diameter is 60 µm, the repetition frequency is 1 kHz, and the pulse width is 60 ps. The pattern array is a triangular array, the triangles are equilateral triangles with a side length of 60 µm, and the pattern spacing is 100 µm.
[0073] Step 3: Grind the blocky purple phosphorus crystals to obtain a large amount of purple phosphorus powder. Then, disperse the ground purple phosphorus powder in ethanol to prepare a dispersion with a purple phosphorus concentration of 0.8 mg / mL. Then, perform laser irradiation treatment. The parameters of the laser irradiation treatment are: spot diameter of 40µm, repetition frequency of 120 kHz, pulse width of 60ps; laser scanning speed of 500mm / s, and power of 25W.
[0074] Step 4: Place the patterned graphene array sample on a spin coater, and use a pipette to drop the purple phosphorus nanosheet dispersion obtained in Step 3 onto the surface of the patterned graphene array sample, so that the purple phosphorus nanosheets and patterned graphene are combined to form a purple phosphorus / patterned graphene composite sensitive structure. The spin coating method includes three stages: first, spin at 230 r / min for 1 min; then spin at 1400 r / min for 4 min; and finally spin at 2600 r / min for 1 min.
[0075] Step 5: Silver wires are led out from both ends of the composite sensitive structure obtained in Step 4 as electrodes. Connecting the electrodes to the detection circuit yields a purple phosphorus patterned graphene multifunctional sensor. Static and dynamic methods are used to test the gas sensitivity. The test gas is O2, CO2, H2, SO2, or H2S. The gas concentration is 100 ppb-10 ppm. The resistance change rate is 25%, and the sensitivity is 1255.
[0076] Example 10 This embodiment provides a method for fabricating a purple phosphorus / square patterned graphene strain sensor, including the following steps: Step 1: Graphene films were prepared on copper foil using CVD to obtain graphene / copper foil samples. The specific CVD growth parameters were as follows: CH4 flow rate was set to 10 mL / min, H2 flow rate was set to 50 mL / min, Ar flow rate was set to 300 mL / min, growth temperature was 1060℃, and growth time was 10 min. The graphene / copper foil samples were then immersed in a mixed solution of ferric chloride and hydrochloric acid for etching. The ferric chloride solution and hydrochloric acid solution were mixed at a volume ratio of 1:1 and the concentration was 0.8 mol / L. After the copper foil was completely removed, the obtained graphene film was transferred to the surface of a polyethersulfone (PES) substrate.
[0077] Step 2: Patterning the graphene film using a nanosecond laser with a wavelength of 1064 nm, a laser power of 100 W, and a scanning speed of 10 mm / s. -1 The spot diameter is 40 µm, the repetition frequency is 1 kHz, and the pulse width is 150 ns. The pattern array is square, with a side length of 100 µm and a pattern spacing of 100 µm.
[0078] Step 3: Grind the blocky purple phosphorus crystals to obtain a large amount of purple phosphorus powder. Then, disperse the ground purple phosphorus powder in ethanol to prepare a dispersion with a purple phosphorus concentration of 0.7 mg / mL. Then, perform laser irradiation treatment. The parameters of the laser irradiation treatment are: spot diameter of 55µm, repetition frequency of 190 kHz, pulse width of 90 ns, laser scanning speed of 100 mm / s, and power of 10 W.
[0079] Step 4: Place the patterned graphene array sample on a spin coater, and use a pipette to drop the purple phosphorus nanosheet dispersion obtained in Step 3 onto the surface of the patterned graphene array sample, so that the purple phosphorus nanosheets and patterned graphene are combined to form a purple phosphorus / patterned graphene composite sensitive structure. The spin coating method includes three stages: first, spin at 300 r / min for 0.5 min; then spin at 1500 r / min for 3 min; and finally spin at 3000 r / min for 0.5 min.
[0080] Step 5: Silver wires are led out from both ends of the composite sensitive structure obtained in Step 4 as electrodes. Connecting these electrodes to the detection circuit yields a purple phosphorus patterned graphene multifunctional sensor. The strain sensing method is used to test its resistance change under tensile strain conditions of 1-20%. The resistance change rate is 360%, and the sensitivity is 628.
[0081] The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made to the technical solution based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.
Claims
1. A method for preparing a purple phosphorus / patterned graphene composite multifunctional sensor, characterized in that, Includes the following steps: Step 1: Immerse the copper foil sample carrying graphene in an etching solution for etching. After the copper foil is completely removed, transfer the resulting graphene film to a substrate surface. Step 2: The graphene film on the substrate is processed by laser ablation to form a micron-scale patterned graphene array on its surface. Step 3: The bulk purple phosphorus is treated by laser liquid phase exfoliation to obtain a purple phosphorus nanosheet dispersion; Step 4: Coat the obtained purple phosphorus nanosheet dispersion onto the surface of the patterned graphene array to combine the purple phosphorus nanosheets with the patterned graphene to form a purple phosphorus / patterned graphene composite sensitive structure. Step 5: Electrodes are placed at both ends of the obtained composite sensitive structure to obtain the purple phosphorus / patterned graphene composite multifunctional sensor.
2. The method for preparing a purple phosphorus / patterned graphene composite multifunctional sensor according to claim 1, characterized in that, In step 1, the corrosive solution is a mixed solution of ferric chloride and hydrochloric acid.
3. The method for preparing a purple phosphorus / patterned graphene composite multifunctional sensor according to claim 1, characterized in that, In step 2, the laser used in the laser ablation method is a nanosecond laser, a picosecond laser, or a femtosecond laser; the shape of the patterned graphene array is circular, square, triangular, or hexagonal.
4. The method for preparing a purple phosphorus / patterned graphene composite multifunctional sensor according to claim 1, characterized in that, In step 3, the laser liquid phase exfoliation method specifically involves: grinding the bulk purple phosphorus crystals and dispersing them in ethanol to prepare a dispersion with a concentration of 0.5-1 mg / mL, followed by laser irradiation treatment.
5. The method for preparing a purple phosphorus / patterned graphene composite multifunctional sensor according to claim 1, characterized in that, In step 4, the coating method is spin coating; the spin coating method includes three stages: first, rotating at a speed of 180-300 r / min for 0.5-1 min, then rotating at a speed of 1000-1500 r / min for 3-5 min, and finally rotating at a speed of 2000-3000 r / min for 0.5-1 min.
6. The method for preparing a purple phosphorus / patterned graphene composite multifunctional sensor according to claim 1, characterized in that, In step 1, the substrate is a flexible substrate, specifically polydimethylsiloxane or polyethersulfone.
7. The method for preparing a purple phosphorus / patterned graphene composite multifunctional sensor according to claim 1, characterized in that, In step 1, the substrate is a rigid substrate, specifically Si / SiO2 or glass.
8. The method for preparing a purple phosphorus / patterned graphene composite multifunctional sensor according to claim 1, characterized in that, In step 5, the electrode is a silver wire electrode.
9. A purple phosphorus / patterned graphene composite multifunctional sensor, characterized in that, The sensor is prepared by any one of claims 1 to 8; the sensor includes a substrate, a patterned graphene array formed on the substrate, purple phosphorus nanosheets composited on the surface of the patterned graphene array, and electrodes connected to both ends of the composite sensitive structure.
10. An application of the purple phosphorus / patterned graphene composite multifunctional sensor as described in claim 9, characterized in that, The sensor is used to detect at least one parameter selected from temperature, humidity, strain, or gas concentration; the gas includes CO, NH3, NO2, H2O, NO, and N. 2、 O2, CO2, H2, SO2 or H2S.