Molybdenum disulfide-based hydrogen sensitive material and preparation method thereof as well as flexible room-temperature hydrogen sensor as well as preparation method and application of flexible room-temperature hydrogen sensor

Abstract

The invention provides a molybdenum disulfide-based hydrogen sensitive material and a preparation method thereof, and a flexible room-temperature hydrogen sensor and a preparation method and application thereof, and relates to the technical field of gas sensors. The molybdenum disulfide-based hydrogen sensitive material provided by the invention comprises a MoS2 two-dimensional nanosheet and Pd loaded on the MoS2 two-dimensional nanosheet. According to the invention, the MoS2 two-dimensional nanosheet has good conductivity at room temperature, and the loading of Pd can effectively enhance the hydrogen adsorption capacity and electron conduction efficiency of the MoS2 material; and due to the special scale effect of the two-dimensional nanosheet, the stress accumulation in the bending process of the flexible sensitive film can be effectively relieved, and the mechanical property of the flexible sensor is improved. The molybdenum disulfide-based hydrogen sensitive material is combined with a flexible substrate to construct a flexible hydrogen sensor based on Pd-MoS2, and the flexible hydrogen sensor shows excellent hydrogen sensitive characteristics at room temperature, namely high sensitivity, high selectivity and high stability.

Description

Technical Field

[0001] This invention relates to the field of gas sensor technology, and in particular to a molybdenum disulfide-based hydrogen sensitive material and its preparation method, a flexible room temperature hydrogen sensor and its preparation method and application. Background Technology

[0002] With the rapid development of flexible electronics technology, wearable devices, electronic skin, and IoT systems urgently require gas sensors that combine high sensitivity, room temperature operation capability, and mechanical flexibility. Hydrogen (H2), as a clean energy carrier, is widely used in new energy, chemical, and aerospace fields; however, its flammable and explosive properties (explosion limits in air are 4-75 vol%) pose significant safety hazards, necessitating real-time monitoring. Therefore, developing flexible room temperature sensors capable of real-time monitoring of low-concentration hydrogen is of great significance for ensuring industrial safety and human health safety.

[0003] Commonly used metal oxide chemiluminescence sensors typically rely on high-temperature operation (150~400℃) and are based on rigid substrates, making it difficult to meet the requirements for flexible and low-power consumption. Conductive polymers or carbon-based flexible materials suffer from poor room-temperature selectivity and insufficient sensitivity. Two-dimensional materials (such as WS2 and Mxene) and metal-organic frameworks (MOFs) have the advantage of high specific surface area, but their intrinsic hydrogen adsorption energy is low and their conductivity is poor. These problems limit the realization of high-performance flexible room-temperature hydrogen sensors. Summary of the Invention

[0004] In view of this, the purpose of this invention is to provide a molybdenum disulfide-based hydrogen sensitive material and its preparation method, as well as a flexible room-temperature hydrogen sensor and its preparation method and application. The molybdenum disulfide-based hydrogen sensitive material provided by this invention can be used to construct a flexible room-temperature hydrogen sensor, and it exhibits high sensitivity, selectivity, and stability.

[0005] To achieve the above-mentioned objectives, the present invention provides the following technical solution: The present invention provides a molybdenum disulfide-based hydrogen-sensitive material comprising two-dimensional MoS2 nanosheets and Pd loaded on the two-dimensional MoS2 nanosheets.

[0006] This invention provides a method for preparing the molybdenum disulfide-based hydrogen-sensitive material described in the above technical solution, comprising the following steps: MoS2, sodium tartrate, and an organic solvent are mixed to obtain a mixture. The mixture was subjected to ultrasonic intercalation and then centrifuged. The supernatant was taken and dried to obtain MoS2 two-dimensional nanosheets. The dispersion of the MoS2 two-dimensional nanosheets was mixed with PdCl2 and sodium borohydride, and chemically reduced. The resulting product was then vacuum dried to obtain the molybdenum disulfide-based hydrogen-sensitive material.

[0007] Preferably, the mass ratio of MoS2 to sodium tartrate is (150~200):(25~31.25).

[0008] Preferably, the temperature of the mixture during the ultrasonic intercalation treatment is 15~30℃, the ultrasonic power is 350~450 W, and the ultrasonic intercalation treatment time is 3~4 h.

[0009] Preferably, the mass of the PdCl2 is 10-16% of the mass of the MoS2 two-dimensional nanosheets in the dispersion of the MoS2 two-dimensional nanosheets.

[0010] Preferably, the molar ratio of sodium borohydride to PdCl2 is 1.5~2.5:1, and the chemical reduction time is 2~3 hours.

[0011] The present invention provides a flexible room temperature hydrogen sensor, comprising a flexible substrate on which interdigitated electrodes are deposited and a sensitive film covering the surface of the interdigitated electrodes. The sensitive film is formed from the molybdenum disulfide-based hydrogen sensitive material described in the above technical solution or the molybdenum disulfide-based hydrogen sensitive material prepared by the preparation method described in the above technical solution.

[0012] This invention provides a method for fabricating the flexible room temperature hydrogen sensor described above, comprising the following steps: The dispersion of the molybdenum disulfide-based hydrogen sensing material is deposited onto the surface of the interdigitated electrodes on a flexible substrate with interdigitated electrodes deposited thereon to form a sensitive film, thereby obtaining the flexible room temperature hydrogen sensor; the dispersion of the molybdenum disulfide-based hydrogen sensing material is deposited by 3D printing or coating.

[0013] Preferably, when the dispersion of the molybdenum disulfide-based hydrogen-sensitive material is deposited by 3D printing, the 3D printing is performed using a vision dispensing machine, the dispensing pressure is 20~30 kPa, the temperature of the dispensing machine's flat worktable is set to 35~43℃, the frequency of the dispensing machine's piezoelectric valve is 190 Hz, the number of dispensing times is 2~3, and the concentration of the dispersion of the molybdenum disulfide-based hydrogen-sensitive material is 8~15 mg / mL; when the dispersion of the molybdenum disulfide-based hydrogen-sensitive material is deposited by coating, the concentration of the dispersion of the molybdenum disulfide-based hydrogen-sensitive material is 2~4 mg / mL.

[0014] This invention provides the application of the flexible room temperature hydrogen sensor described in the above technical solutions or the flexible room temperature hydrogen sensor prepared by the above technical solutions in monitoring ambient hydrogen.

[0015] This invention provides a molybdenum disulfide-based hydrogen sensing material, comprising two-dimensional MoS2 nanosheets and Pd loaded on the MoS2 nanosheets (denoted as Pd-MoS2 material). In this invention, the MoS2 nanosheets exhibit good conductivity at room temperature, and the loading of Pd effectively enhances the hydrogen adsorption capacity and electronic conductivity of the MoS2 material. The molybdenum disulfide-based hydrogen sensing material provided by this invention exhibits good hydrogen adsorption capacity at room temperature, high conductivity (faster response and recovery speed), high sensitivity, good selectivity, and high stability. Furthermore, the unique scale effect of the two-dimensional nanosheets effectively alleviates stress accumulation during the bending process of the flexible sensing membrane, thus significantly improving the mechanical properties of the flexible sensor.

[0016] This invention provides a flexible room-temperature hydrogen sensor, comprising a flexible substrate with interdigitated electrodes deposited thereon and a sensitive film covering the surface of the interdigitated electrodes. The sensitive film is formed from the molybdenum disulfide-based hydrogen sensitive material described in the above-described technical solutions or prepared by the methods described in the above-described technical solutions. This invention combines the molybdenum disulfide-based hydrogen sensitive material with a flexible substrate to construct a Pd-MoS2-based flexible gas sensor, exhibiting excellent hydrogen sensitivity characteristics at room temperature, with high sensitivity, high selectivity, and high stability (no baseline drift after multiple response recovery). The flexible room-temperature hydrogen sensor provided by this invention, through size design, has the potential to accurately monitor ambient hydrogen concentration in confined spaces.

[0017] This invention provides a method for fabricating the flexible room temperature hydrogen sensor described above. Using 3D printing, a flexible sensor with good uniformity can be fabricated, which can still maintain good gas sensing performance after dozens of bends. This also provides a way for the subsequent large-scale fabrication of flexible sensors. Attached Figure Description

[0018] Figure 1 The repeatability resistance test curves of the hydrogen sensor based on 14Pd-MoS2 sensitive material in Example 1 are shown in air and 1000 ppm hydrogen at room temperature. Figure 2 The continuous resistance test curves of the hydrogen sensor based on 14Pd-MoS2 sensitive material in Example 1 at room temperature in hydrogen atmospheres of 150, 300, 1000, 5000, 10000, and 15000 ppm are shown. Figure 3 The scatter plot shows the response values ​​of the hydrogen sensor based on 14Pd-MoS2 sensing material in Example 1 at room temperature under hydrogen atmospheres of 150, 300, 1000, 5000, 10000, and 15000 ppm. Figure 4The following graphs are provided: a) Continuous response graph of hydrogen sensor based on 10Pd-MoS2-O sensitive material in Comparative Example 2 under hydrogen atmospheres of 1000, 5000, and 10000 ppm; b) Continuous response graph of hydrogen sensor based on 12Pd-MoS2-O sensitive material in Comparative Example 3 under hydrogen atmospheres of 1000, 5000, 10000, and 15000 ppm; c) Continuous response graph of hydrogen sensor based on 14Pd-MoS2-O sensitive material in Comparative Example 1 under hydrogen atmospheres of 1000, 5000, 10000, and 15000 ppm; d) Continuous response graph of hydrogen sensor based on 16Pd-MoS2-O sensitive material in Comparative Example 4 under hydrogen atmospheres of 1000, 5000, 10000, and 15000 ppm. Figure 5 For a) Comparative Example 2, a hydrogen sensor based on 10Pd-MoS2-O sensitive material; b) Comparative Example 1, a hydrogen sensor based on 14Pd-MoS2-O; and c) Example 1, a hydrogen sensor based on 14Pd-MoS2 sensitive material, showing the function curve of the interdigitated electrode resistance changing over time during a cycle of being placed in a 1000 ppm hydrogen atmosphere and then in an air atmosphere. Figure 6 The interdigitated electrode response values ​​of the hydrogen sensor based on 14Pd-MoS2 nanosheet sensitive material in Example 1 at room temperature operating temperature in atmospheres of 1000 ppm hydrogen, 10000 ppm methane, 100 ppm methanol, 100 ppm ammonia, 100 ppm CO, 20 ppm toluene and 5 ppm H2S. Figure 7 This is a three-dimensional surface morphology diagram of the sensitive membrane in the room temperature hydrogen sensor of the embodiment after bending. Figure 7 a) shows the three-dimensional surface morphology of the hydrogen sensor sensitive film prepared by the drop-coating method using 14Pd-MoS2 nanosheet sensitive material in Example 1 after 0 90° bends; b) to d) show the three-dimensional surface morphology of the hydrogen sensor sensitive film prepared by the 3D printing method using 14Pd-MoS2 nanosheet sensitive material in Example 2 after 0, 30, and 90 90 90° bends. Figure 8 The hydrogen sensor sensitive film prepared by 3D printing using 14Pd-MoS2 nanosheet sensitive material based on Example 2 shows the continuous response of the hydrogen sensor sensitive film under a hydrogen atmosphere of 1000, 5000, 10000, and 15000 ppm after being bent at 90° 0, 30, and 90 times, respectively. Figure 9 This is a conceptual diagram of a gas sensing test system consisting of a flow controller (MFC), a humidity generator, a test chamber, a DC power supply, a multimeter, flow control and numerical recording equipment, and an exhaust gas treatment device. Detailed Implementation

[0019] The present invention provides a molybdenum disulfide-based hydrogen-sensitive material comprising two-dimensional MoS2 nanosheets and Pd loaded on the two-dimensional MoS2 nanosheets.

[0020] In this invention, the molybdenum disulfide-based hydrogen-sensitive material is designated as Pd-MoS2. In this invention, the MoS2 two-dimensional nanosheets exhibit good conductivity at room temperature, and the Pd anchored on sulfur vacancies helps accelerate the dissociation of H2 into H+. + This process further accelerates the electron conduction efficiency of the system reaction, thus enabling the hydrogen sensor constructed with the aforementioned hydrogen-sensitive material to operate efficiently at room temperature. In this embodiment of the invention, the molybdenum disulfide-based hydrogen-sensitive material is also referred to as a two-dimensional nanosheet-sensitive material.

[0021] This invention provides a method for preparing the molybdenum disulfide-based hydrogen-sensitive material described in the above technical solution, comprising the following steps: MoS2, sodium tartrate, and an organic solvent are mixed to obtain a mixture. The mixture was subjected to ultrasonic intercalation and centrifugation. The supernatant was dried to obtain MoS2 two-dimensional nanosheets (few-layer MoS2 two-dimensional nanosheets). The dispersion of the MoS2 two-dimensional nanosheets was mixed with PdCl2 and sodium borohydride and chemically reduced to obtain the molybdenum disulfide-based hydrogen-sensitive material.

[0022] Unless otherwise specified, all raw materials involved in this invention are commercially available products well known in the art.

[0023] This invention involves mixing MoS2, sodium tartrate, and an organic solvent to obtain a mixture.

[0024] In this invention, the size of the MoS2 is preferably <2 μm (the MoS2 in the examples is in bulk shape), the organic solvent is preferably NMP (N-methylpyrrolidone), and the mass ratio of the MoS2 to sodium tartrate (C4H4Na2O6) is preferably (150~200):(25~31.25), which can be 150:25.

[0025] In this invention, the preferred method for mixing MoS2, sodium tartrate, and the organic solvent is as follows: The MoS2 is mixed with a first portion of the organic solvent to obtain a MoS2 dispersion; The sodium tartrate is mixed with the remaining organic solvent to obtain a sodium tartrate dispersion. The sodium tartrate dispersion was added to the MoS2 dispersion for a third mixing to obtain the mixture.

[0026] In this invention, the preferred ratio of MoS2 to the first portion of the organic solvent is (150~200) mg:(25~35) mL, which can be 150 mg:25 mL. The first mixing is preferably stirred, with a stirring speed of 500 r / min and a stirring time of 10 min. In this invention, the preferred ratio of sodium tartrate to the remaining portion of the organic solvent is (25~31.25) mg:5 mL, which can be 25 mg:5 mL. The first portion of the organic solvent and the remaining portion of the organic solvent constitute the entirety of the organic solvent. This invention does not have specific requirements for the second mixing method, as long as sodium tartrate is uniformly dispersed in the organic solvent. In this invention, the third mixing is preferably stirred, with a stirring speed of 300 r / min and a stirring time of 5 min. This invention uses a sodium tartrate dispersion to add sodium tartrate, which avoids excessive accumulation of sodium tartrate in some molybdenum disulfide materials due to direct addition, thus preventing an impact on the overall ultrasonic intercalation effect.

[0027] After obtaining the mixture, the present invention performs ultrasonic intercalation treatment on the mixture and centrifuges it, and takes the supernatant for drying to obtain MoS2 two-dimensional nanosheets.

[0028] In this invention, the temperature of the mixture during the ultrasonic intercalation treatment is preferably 15~30℃, the ultrasonic power is preferably 350~450 W, and can be 400 W. The duration of the ultrasonic intercalation treatment is preferably 3~4 h. The ultrasonic intercalation treatment is preferably carried out under ice bath conditions to ensure that the temperature of the mixture is 15~30℃. During the ultrasonic intercalation treatment, the mixture is preferably taken out every 40 min and stirred at a speed of 500 r / min for 3 min to avoid local precipitation of MoS2 blocks during the ultrasonic process as much as possible, thereby promoting the ultrasonic exfoliation effect.

[0029] This invention utilizes sodium tartrate to intercalate and ultrasonically exfoliate MoS2, obtaining few-layer MoS2 two-dimensional nanosheets. The intercalation effect of sodium tartrate significantly reduces the van der Waals forces between MoS2 layers, exfoliating to form few-layer MoS2 nanosheets and increasing the interlayer spacing, thereby improving the specific surface area for gas-material contact and preventing the subsequent aggregation of Pd nanoparticles. Furthermore, during the preparation of the MoS2 two-dimensional nanosheets, intrinsic defects inevitably arise due to the thermodynamic spontaneous process, forming sulfur vacancies. Simultaneously, the use of sodium borohydride as a reducing agent in this invention, with its strong reducing properties, also leads to the loss of sulfur atoms, creating more sulfur vacancies. These sulfur vacancies are beneficial for Pd loading, and Pd anchored to these sulfur vacancies helps accelerate the dissociation of H2 into H+. +This process further accelerates the electron conduction efficiency of the system reaction, thereby ensuring that the prepared molybdenum disulfide-based sensitive material has good sensitivity to hydrogen at room temperature.

[0030] In this invention, the centrifugation speed is preferably 1500 r / min, and the centrifugation time is preferably 10 min; the drying temperature is preferably 60℃. This invention obtains MoS2 nanosheets with fewer layers that are well-exfoliated after ultrasonication through centrifugation, while removing poorly exfoliated multilayer or bulk MoS2 nanosheets. This ensures, to a certain extent, good uniformity of the obtained MoS2 nanosheets and improves the performance of the prepared molybdenum disulfide-based sensitive material.

[0031] After obtaining MoS2 two-dimensional nanosheets, the present invention mixes the dispersion of the MoS2 two-dimensional nanosheets with PdCl2 and sodium borohydride, performs chemical reduction, and vacuum dries the resulting product to obtain the molybdenum disulfide-based hydrogen-sensitive material.

[0032] In this invention, the dispersion of the MoS2 two-dimensional nanosheets is preferably formed by dispersing the MoS2 two-dimensional nanosheets in NMP, and the concentration of the dispersion is preferably 5 mg / mL. In this invention, the mass of PdCl2 is preferably 10-16% of the mass of the MoS2 two-dimensional nanosheets in the dispersion, and can be 10%, 11%, 12%, 13%, 14%, 15%, or 16%. By loading Pd in ​​this ratio, this invention prepares a sensitive material with excellent hydrogen response at room temperature. In this invention, the molar ratio of sodium borohydride (NaBH4) to PdCl2 is preferably 1.5-2.5:1, and the sodium borohydride acts as a reducing agent.

[0033] In this invention, the preferred method for mixing the dispersion of MoS2 two-dimensional nanosheets with PdCl2 and sodium borohydride is as follows: PdCl2 was added to the dispersion of the MoS2 two-dimensional nanosheets and stirred. Sodium borohydride was added to the resulting mixture. The stirring speed was preferably 500 r / min and the stirring time was preferably 5 min.

[0034] In this invention, the chemical reduction time is preferably 2-3 h, and can be 2.5 h; the chemical reduction is preferably carried out under stirring conditions, and the stirring speed is preferably 800 r / min. This invention utilizes the chemical reduction method to treat MoS2 nanosheets with Pd loading. The chemical reduction method has the advantages of low temperature, high efficiency, and controllable liquid-phase reduction, and is a universal strategy for reducing and generating uniform Pd nanoparticles.

[0035] After the chemical reduction is completed, the resulting reaction solution is preferably washed and centrifuged once sequentially with NMP, deionized water, and anhydrous ethanol. The resulting product (precipitate) is dispersed in anhydrous ethanol and then vacuum dried to obtain the molybdenum disulfide-based hydrogen-sensitive material. In this invention, the preferred speed for washing and centrifugation is 9000 r / min, and the preferred washing and centrifugation time with NMP, deionized water, and anhydrous ethanol is 8 min. The preferred temperature for vacuum drying is 60℃, and the preferred time is 6 h. The vacuum drying is specifically carried out in a vacuum oven. Using a vacuum oven for low-temperature drying can effectively prevent the reduction of Pd loaded on the MoS2 material from being oxidized during this process.

[0036] The present invention provides a flexible room temperature hydrogen sensor, comprising a flexible substrate on which interdigitated electrodes are deposited and a sensitive film covering the surface of the interdigitated electrodes. The sensitive film is formed from the molybdenum disulfide-based hydrogen sensitive material described in the above technical solution or the molybdenum disulfide-based hydrogen sensitive material prepared by the preparation method described in the above technical solution.

[0037] In this invention, the flexible substrate is preferably made of polyimide (PI); the interdigitated electrodes are preferably platinum electrodes; in an embodiment of this invention, 10 pairs of platinum electrodes, each 100 μm wide and 7.7 mm long, are deposited on a flexible PI substrate with a side length of 10 mm, and the spacing between the electrodes is 50 μm.

[0038] The present invention does not have special requirements on the thickness of the sensitive membrane, as long as the membrane thickness is uniform.

[0039] This invention combines Pd-MoS2 nanosheets with a flexible substrate to achieve the effective construction of a flexible room temperature hydrogen sensor. The resulting flexible sensor exhibits excellent room temperature hydrogen sensitivity characteristics: high sensitivity and selectivity, significantly higher response and gas selectivity to hydrogen compared to common interfering gases (such as ammonia, carbon monoxide, methane, toluene, hydrogen sulfide, methanol vapor, etc.), as well as good room temperature stability.

[0040] This invention provides a method for fabricating the flexible room temperature hydrogen sensor described above, comprising the following steps: The dispersion of the molybdenum disulfide-based hydrogen sensing material is deposited onto the surface of the interdigitated electrodes on a flexible substrate with interdigitated electrodes deposited thereon to form a sensitive film, thereby obtaining the flexible room temperature hydrogen sensor; the dispersion of the molybdenum disulfide-based hydrogen sensing material is deposited by 3D printing or coating.

[0041] In this invention, the solvent for the dispersion of the molybdenum disulfide-based hydrogen-sensitive material is preferably anhydrous ethanol.

[0042] In this invention, when the dispersion of the molybdenum disulfide-based hydrogen-sensitive material is deposited via 3D printing, the 3D printing is preferably performed using a vision dispensing machine. The dispensing pressure is preferably 20-30 kPa, and can be 25 kPa. The temperature of the dispensing machine's flat worktable is set to 35-43°C, and can be 40°C (to evaporate the solvent in the dispersion of the molybdenum disulfide-based hydrogen-sensitive material and simultaneously pre-age the device). The frequency of the dispensing machine's piezoelectric valve is preferably 190 Hz, the number of dispensing passes is preferably 2-3, and the concentration of the dispersion of the molybdenum disulfide-based hydrogen-sensitive material (also known as printing ink) is preferably 8-15 mg / mL, and can be 10 mg / mL. In this embodiment of the invention, the vision dispensing machine used is model SEC-551B. In this invention, the dispersion of the molybdenum disulfide-based hydrogen-sensitive material (i.e., printing ink) is preferably obtained by grinding the molybdenum disulfide-based hydrogen-sensitive material and then ultrasonically mixing it with anhydrous ethanol; the grinding time is preferably 0.5 h.

[0043] In this invention, when the dispersion of the molybdenum disulfide-based hydrogen sensing material is deposited by coating, the concentration of the dispersion is preferably 2-4 mg / mL. The dispersion is preferably obtained by ultrasonically mixing the molybdenum disulfide-based hydrogen sensing material with anhydrous ethanol. In this invention, the coating method is preferably drop coating, with uniform coating as the standard. In an embodiment of this invention, 6-8 μL of the hydrogen sensing material dispersion is drop-coated onto the surface of 10 pairs of platinum electrodes, each 100 μm wide and 7.7 mm long. After coating, drying is performed, preferably by tungsten filament lamp irradiation. The tungsten filament lamp irradiation power is preferably 250 W, the distance is preferably 35-40 cm, and the irradiation time is preferably 8-15 min, or 10 min. Through drying, the solvent evaporates, and the sensor is initially aged and stabilized.

[0044] This invention provides the application of the flexible room temperature hydrogen sensor described in the above technical solutions, or the flexible room temperature hydrogen sensor prepared by the above preparation methods, in monitoring ambient hydrogen. This invention does not impose any special requirements on the application method; any application method well-known to those skilled in the art can be used. In this invention, the flexible room temperature hydrogen sensor can be applied to the wearable field.

[0045] To further illustrate the present invention, the following detailed descriptions, in conjunction with examples, illustrate the molybdenum disulfide-based hydrogen sensitive material and its preparation method, as well as the flexible room-temperature hydrogen sensor and its preparation method and applications provided by the present invention. However, these descriptions should not be construed as limiting the scope of protection of the present invention.

[0046] Example 1 (1) The two-dimensional nanosheet sensitive material (denoted as 14Pd-MoS2) is prepared by the following method: 150 mg of MoS2 (size < 2 μm) was dispersed in 25 mL of NMP (N-methylpyrrolidone) and stirred under magnetic stirring (500 r / min) for 10 min to obtain a MoS2 dispersion. 25 mg of sodium tartrate was uniformly dispersed in 5 mL of NMP to obtain a sodium tartrate dispersion. The sodium tartrate dispersion was added to the MoS2 dispersion and stirred under magnetic stirring (300 r / min) for 5 min. The resulting mixture was then subjected to ice bath ultrasonic intercalation treatment for 4 h (power 400 W, ensuring the solution temperature was 15~30℃, during which the mixture was taken out every 40 min and stirred under magnetic stirring (500 r / min) for 3 min). The mixture obtained by ultrasonic intercalation was centrifuged at 1500 r / min for 10 min, and the MoS2 solution in the upper part of the centrifuge tube was retained; the obtained MoS2 solution was dried in an oven at 60℃ to obtain few-layer MoS2 nanosheets. The MoS2 nanosheets were dispersed in NMP to form a 5 mg / mL MoS2 nanosheet dispersion. Take 20 mL of the MoS2 nanosheet dispersion, add PdCl2 and mix well (PdCl2 accounts for 14% of the mass fraction of MoS2 nanosheets, and stir magnetically (500 r / min) for 5 min); then add sodium borohydride (NaBH4) (the molar ratio of NaBH4 to the aforementioned PdCl2 is 1.5:1), and carry out chemical reduction under magnetic stirring (800 r / min) for 2.5 h; wash the resulting dispersion with NMP, deionized water, and anhydrous ethanol once each, and centrifuge once (9000 r / min, 8 min) to obtain Pd-MoS2 precipitate; The obtained precipitate was redispersed in 8 mL of anhydrous ethanol and dried in a vacuum oven at 60 °C for 6 h to obtain a two-dimensional nanosheet sensitive material, denoted as 14Pd-MoS2.

[0047] (2) A flexible room temperature hydrogen sensor based on 14Pd-MoS2 two-dimensional nanosheet sensitive material is prepared by the following method: Take 2 mg of 14Pd-MoS2 two-dimensional nanosheet material and add it to anhydrous ethanol and sonicate to form a 4 mg / mL 14Pd-MoS2 dispersion. 8 μL of the 14Pd-MoS2 dispersion was pipetted and uniformly dropped onto a PI flexible interdigitated electrode (the electrode is 10 pairs of 100 μm wide and 7.7 mm long platinum electrodes deposited on a flexible PI substrate with a side length of 10 mm, with a spacing of 50 μm between the electrodes), thus initially obtaining a flexible 14Pd-MoS2 sensor. The initially obtained flexible 14Pd-MoS2 sensor was irradiated under a tungsten filament lamp for 10 min (power 250 W, distance 40 cm) to evaporate anhydrous ethanol and preliminarily age and stabilize the sensor (the process of drop-coating the 14Pd-MoS2 dispersion onto the tungsten filament lamp was repeated twice to form a more uniform flexible sensor sensitive film).

[0048] Example 2 (1) The two-dimensional nanosheet sensitive material (denoted as 14Pd-MoS2) is prepared by the following method: 150 mg of MoS2 (size < 2 μm) was dispersed in 25 mL of NMP (N-methylpyrrolidone) and stirred under magnetic stirring (500 r / min) for 10 min to obtain a MoS2 dispersion. 25 mg of sodium tartrate was uniformly dispersed in 5 mL of NMP to obtain a sodium tartrate dispersion. The sodium tartrate dispersion was added to the MoS2 dispersion and stirred under magnetic stirring (300 r / min) for 5 min. The resulting mixture was then subjected to ice bath ultrasonic intercalation treatment for 4 h (power 400 W, ensuring the solution temperature was 15~30℃, during which the mixture was taken out every 40 min and stirred under magnetic stirring (500 r / min) for 3 min). The mixture obtained by ultrasonic intercalation was centrifuged at 1500 r / min for 10 min, and the MoS2 solution in the upper part of the centrifuge tube was retained; the obtained MoS2 solution was dried in an oven at 60℃ to obtain few-layer MoS2 nanosheets. The MoS2 nanosheets were dispersed in NMP to form a 5 mg / mL MoS2 nanosheet dispersion. Take 20 mL of the MoS2 nanosheet dispersion, add PdCl2 and mix well (PdCl2 accounts for 14% of the mass fraction of MoS2 nanosheets, and stir magnetically (500 r / min) for 5 min); then add sodium borohydride (NaBH4) (the molar ratio of NaBH4 to the aforementioned PdCl2 is 1.5:1), and carry out chemical reduction under magnetic stirring (800 r / min) for 2.5 h; wash the resulting dispersion with NMP, deionized water, and anhydrous ethanol once each, and centrifuge once (9000 r / min, 8 min) to obtain Pd-MoS2 precipitate; The obtained precipitate was redispersed in 8 mL of anhydrous ethanol and dried in a vacuum oven at 60 °C for 6 h to obtain a two-dimensional nanosheet sensitive material, denoted as 14Pd-MoS2.

[0049] (2) A flexible room temperature hydrogen sensor based on 14Pd-MoS2 two-dimensional nanosheet sensitive material (denoted as 14Pd-MoS2-3D flexible sensor) is prepared as follows: 20 mg of 14Pd-MoS2 two-dimensional nanosheet material was ground for 0.5 h, and anhydrous ethanol was added and sonicated to form a 10 mg / mL 14Pd-MoS2 dispersion (printing ink). The above dispersion was transferred into the cavity of the SEC-551B vision dispensing machine. The PI flexible interdigitated electrodes (10 pairs of 100 μm wide and 7.7 mm long platinum electrodes deposited on a flexible PI substrate with a side length of 10 mm, with an electrode spacing of 50 μm) were placed on the dispensing machine's dispensing platform for two dispensing processes (dispensing air pressure 25 kPa, dispensing machine piezoelectric valve frequency 190 Hz). The dispensing machine's operating platform was set to a constant temperature of 40℃ to help the ethanol evaporate and to pre-age the device, so as to finally form a uniform sensor sensitive film and obtain a 14Pd-MoS2-3D flexible sensor.

[0050] Comparative Example 1 The two-dimensional nanosheet sensitive material (denoted as 14Pd-MoS2-O) is prepared by the following method: 150 mg of MoS2 (size < 2 μm) was dispersed in 25 mL of NMP (N-methylpyrrolidone) and stirred for 10 min under magnetic stirring (500 r / min) to obtain a MoS2 dispersion. 25 mg of sodium tartrate was uniformly dispersed in 5 mL of NMP to obtain a sodium tartrate dispersion. The sodium tartrate dispersion was added to the MoS2 dispersion and stirred under magnetic stirring (300 r / min) for 5 min. The resulting mixture was then subjected to ice bath ultrasonic intercalation treatment for 4 h (power 400 W, ensuring the solution temperature was 15~30℃, during which the mixture was taken out every 40 min and stirred under magnetic stirring (500 r / min) for 3 min). PdCl2 was added to the MoS2 precursor solution obtained by ultrasonic intercalation and mixed thoroughly (PdCl2 accounted for 14% of the mass fraction of MoS2, and the mixture was stirred magnetically (500 r / min) for 5 min); then sodium borohydride (NaBH4) was added (the molar ratio of NaBH4 to the aforementioned PdCl2 was 1.5:1), and chemical reduction was carried out under magnetic stirring (800 r / min) for 2.5 h; the resulting dispersion was washed successively with NMP, deionized water, and anhydrous ethanol, and centrifuged once each (9000 r / min, 8 min) to obtain Pd-MoS2 precipitate; The obtained precipitate was redispersed in 8 mL of anhydrous ethanol and dried in an oven at 80 °C for 10 h (this drying condition will cause some Pd to be oxidized) to obtain two-dimensional nanosheets, denoted as 14Pd-MoS2-O.

[0051] (2) A flexible room temperature hydrogen sensor based on 14Pd-MoS2-O two-dimensional nanosheet sensitive material, the preparation method of which is as follows: Take 2 mg of 14Pd-MoS2-O two-dimensional nanosheet material and add it to anhydrous ethanol and sonicate to form a 4 mg / mL 14Pd-MoS2-O dispersion; 8 μL of the 14Pd-MoS2-O dispersion was pipetted and uniformly dropped onto a PI flexible interdigitated electrode (the electrode is 10 pairs of 100 μm wide and 7.7 mm long platinum electrodes deposited on a flexible PI substrate with a side length of 10 mm, with a spacing of 50 μm between the electrodes), thus initially obtaining a flexible 14Pd-MoS2-O sensor. The initially obtained flexible 14Pd-MoS2-O sensor was irradiated under a tungsten filament lamp for 10 min (power 250 W, distance 40 cm) to evaporate anhydrous ethanol and preliminarily age and stabilize the sensor (the process of drop-coating the 14Pd-MoS2-O dispersion onto the tungsten filament lamp was repeated twice to form a more uniform flexible sensor sensitive film).

[0052] Comparative Example 2 (1) Two-dimensional nanosheet sensitive material (denoted as 10Pd-MoS2-O) is prepared as follows: 150 mg of MoS2 (size < 2 μm) was dispersed in 25 mL of NMP (N-methylpyrrolidone) and stirred for 10 min under magnetic stirring (500 r / min) to obtain a MoS2 dispersion. 25 mg of sodium tartrate was uniformly dispersed in 5 mL of NMP to obtain a sodium tartrate dispersion. The sodium tartrate dispersion was added to the MoS2 dispersion and stirred under magnetic stirring (300 r / min) for 5 min. The resulting mixture was then subjected to ice bath ultrasonic intercalation treatment for 4 h (power 400 W, ensuring the solution temperature was 15~30℃, during which the mixture was taken out every 40 min and stirred under magnetic stirring (500 r / min) for 3 min). PdCl2 was added to the MoS2 precursor solution obtained by ultrasonic intercalation and mixed thoroughly (PdCl2 accounted for 10% of the mass fraction of MoS2, and the mixture was stirred magnetically (500 r / min) for 5 min); then sodium borohydride (NaBH) was added (the molar ratio of NaBH to the aforementioned PdCl2 was 1.5:1), and chemical reduction was carried out under magnetic stirring (800 r / min) for 2.5 h; the resulting dispersion was washed successively with NMP, deionized water, and anhydrous ethanol solution, and centrifuged once (9000 r / min, 8 min) to obtain Pd-MoS2 precipitate; The obtained precipitate was redispersed in 8 mL of anhydrous ethanol and dried in an oven at 80 °C for 10 h to obtain two-dimensional nanosheets, denoted as 10Pd-MoS2-O.

[0053] (2) A flexible room temperature hydrogen sensor based on 10Pd-MoS2-O two-dimensional nanosheet sensitive material is prepared by the following method: Take 2 mg of 10Pd-MoS2-O two-dimensional nanosheet material and add it to anhydrous ethanol and sonicate to form a 4 mg / mL 10Pd-MoS2-O dispersion. 8 μL of the 10Pd-MoS2-O dispersion was pipetted and uniformly dropped onto a flexible interdigitated electrode (the electrode is 10 pairs of platinum electrodes, each 100 μm wide and 7.7 mm long, deposited on a flexible PI substrate with a side length of 10 mm, with a spacing of 50 μm between the electrodes), thus initially obtaining a flexible 10Pd-MoS2-O sensor. The initially obtained flexible 10Pd-MoS2-O sensor was dried under a tungsten filament lamp for 10 min (power 250 W) to evaporate anhydrous ethanol and preliminarily age and stabilize the sensor (the process of drop-coating the 10Pd-MoS2-O dispersion onto the tungsten filament lamp was repeated twice to form a relatively uniform flexible sensor sensitive film).

[0054] Comparative Example 3 (1) The two-dimensional nanosheet sensitive material (denoted as 12Pd-MoS2-O) is prepared by the following method: 150 mg of MoS2 (size < 2 μm) was dispersed in 25 mL of NMP (N-methylpyrrolidone) and stirred for 10 min under magnetic stirring (500 r / min) to obtain a MoS2 dispersion. 25 mg of sodium tartrate was uniformly dispersed in 5 mL of NMP to obtain a sodium tartrate dispersion. The sodium tartrate dispersion was added to the MoS2 dispersion and stirred under magnetic stirring (300 r / min) for 5 min. The resulting mixture was then subjected to ice bath ultrasonic intercalation treatment for 4 h (power 400 W, ensuring the solution temperature was 15~30℃, during which the mixture was taken out every 40 min and stirred under magnetic stirring (500 r / min) for 3 min). PdCl2 was added to the MoS2 precursor solution obtained by ultrasonic intercalation and mixed thoroughly (PdCl2 accounted for 12% of the mass fraction of MoS2, and the mixture was stirred magnetically (500 r / min) for 5 min); then sodium borohydride (NaBH4) was added (the molar ratio of NaBH4 to the aforementioned PdCl2 was 1.5:1), and chemical reduction was carried out under magnetic stirring (800 r / min) for 2.5 h; the resulting dispersion was washed and centrifuged once each with NMP, deionized water, and anhydrous ethanol solution (9000 r / min, 8 min) to obtain Pd-MoS2 precipitate; The obtained precipitate was redispersed in 8 mL of anhydrous ethanol and dried in an oven at 80 °C for 10 h to obtain two-dimensional nanosheets, denoted as 12Pd-MoS2-O.

[0055] (2) A flexible room temperature hydrogen sensor based on 12Pd-MoS2-O two-dimensional nanosheet sensitive material, the preparation method of which is as follows: Take 2 mg of 12Pd-MoS2-O two-dimensional nanosheet material and add it to anhydrous ethanol and sonicate to form a 4 mg / mL 12Pd-MoS2-O dispersion. 8 μL of the 12Pd-MoS2-O dispersion was pipetted and uniformly dropped onto a flexible interdigitated electrode (the electrode is 10 pairs of platinum electrodes, each 100 μm wide and 7.7 mm long, deposited on a flexible PI substrate with a side length of 10 mm, with a spacing of 50 μm between the electrodes), thus initially obtaining a flexible 12Pd-MoS2-O sensor. The initially obtained flexible 12Pd-MoS2-O sensor was irradiated under a tungsten filament lamp for 10 min (power 250 W, distance 40 cm) to evaporate anhydrous ethanol and to preliminarily age and stabilize the sensor (the process of dropping the 12Pd-MoS2-O dispersion onto the tungsten filament lamp for drying was repeated twice to form a more uniform flexible sensor sensitive film).

[0056] Comparative Example 4 (1) 150 mg of MoS2 (size < 2 μm) was dispersed in 25 mL of NMP (N-methylpyrrolidone) and stirred for 10 min under magnetic stirring (500 r / min) to obtain a MoS2 dispersion; 25 mg of sodium tartrate was uniformly dispersed in 5 mL of NMP to obtain a sodium tartrate dispersion. The sodium tartrate dispersion was added to the MoS2 dispersion and stirred under magnetic stirring (300 r / min) for 5 min. The resulting mixture was then subjected to ice bath ultrasonic intercalation treatment for 4 h (power 400 W, ensuring the solution temperature was 15~30℃, during which the mixture was taken out every 40 min and stirred under magnetic stirring (500 r / min) for 3 min). PdCl2 was added to the MoS2 precursor solution obtained by ultrasonic intercalation and mixed thoroughly (PdCl2 accounted for 16% of the mass fraction of MoS2, and the mixture was stirred magnetically (500 r / min) for 5 min); then sodium borohydride (NaBH4) was added (the molar ratio of NaBH4 to the aforementioned PdCl2 was 1.5:1), and chemical reduction was carried out under magnetic stirring (800 r / min) for 2.5 h; the resulting dispersion was washed and centrifuged once each with NMP, deionized water, and anhydrous ethanol solution (9000 r / min, 8 min) to obtain Pd-MoS2 precipitate; The obtained precipitate was redispersed in 8 mL of anhydrous ethanol and dried in an oven at 80 °C for 10 h to obtain two-dimensional nanosheets, denoted as 16Pd-MoS2-O.

[0057] (2) A flexible room temperature hydrogen sensor based on 16Pd-MoS2-O two-dimensional nanosheet sensitive material is prepared by the following method: Take 2 mg of 16Pd-MoS2-O two-dimensional nanosheet material and add it to anhydrous ethanol and sonicate to form a 4 mg / mL 16Pd-MoS2-O dispersion. 8 μL of the 16Pd-MoS2-O dispersion was pipetted and uniformly dropped onto a flexible interdigitated electrode (the electrode is 10 pairs of 100 μm wide and 7.7 mm long platinum electrodes deposited on a flexible PI substrate with a side length of 10 mm, with a spacing of 50 μm between the electrodes), thus initially obtaining a flexible 16Pd-MoS2-O sensor. The initially obtained flexible 16Pd-MoS2-O sensor was irradiated under a tungsten filament lamp for 10 min (power 250 W, distance 40 cm) to evaporate anhydrous ethanol and preliminarily age and stabilize the sensor (the process of dropping the 16Pd-MoS2-O dispersion onto the tungsten filament lamp for drying was repeated twice to form a more uniform flexible sensor sensitive film).

[0058] Test case The sensor's sensitivity to hydrogen was tested using... Figure 9 The gas sensing dynamic testing system shown consists of a flow controller (MFC), a humidity generator, a test chamber, a DC power supply, a multimeter, flow control and data recording equipment, and an exhaust gas treatment device. The testing method is as follows: During testing, the corresponding gas mixing values ​​are input into the computer-controlled gas mixing system. The introduced gases (test gas, O2, N2) are precisely controlled by the gas flow controller (MFC) according to the set values ​​into the test chamber. (When the target test gas is not introduced, the O2 and N2 ratio is controlled to simulate the air environment; the N2 generated by the humidity generator forms humid N2; and the proportion of humid N2 in the overall gas atmosphere is controlled to simulate different humidity test environments.) A stable power supply voltage is provided by the power supply. The computer system records the voltage division between the sensor and the matching resistor in the test chamber in real time during the test process, and finally calculates the resistance of the sensor during operation.

[0059] The test results are as follows (in the following figures, R...). g R is the resistance value of the sensor when it is placed in the test gas. a The resistance of the sensor when placed in the air is given by the response value S=R. a / R g (All tests were conducted under conditions of RH=20%) Figure 1 At room temperature operating temperature, using Figure 9 The gas dynamic testing system provides repeatability resistance test curves for the hydrogen sensor based on 14Pd-MoS2 sensitive material in Example 1, in air and at a hydrogen concentration of 1000 ppm. Figure 1 It can be seen that the resistance of the sensor decreases under hydrogen atmosphere at room temperature. When the hydrogen is stopped and the sensor returns to the air atmosphere, the resistance of the sensor increases and gradually returns to the original air atmosphere resistance level. The calculated response value of the hydrogen sensor based on 14Pd-MoS2 sensitive material to 1000ppm hydrogen concentration is 5.12.

[0060] Figure 2 At room temperature operating temperature, using Figure 9 The gas dynamic testing system was used to measure the continuous resistance curves of the hydrogen sensor based on 14Pd-MoS2 sensitive material in Example 1 in hydrogen atmospheres of 150, 300, 1000, 5000, 10000, and 15000 ppm. Figure 2 It can be seen that the higher the concentration of hydrogen gas introduced at room temperature, the greater the change in resistance of the hydrogen sensor based on the 14Pd-MoS2 sensitive material. When the hydrogen gas is stopped and the sensor returns to the air atmosphere, the sensor resistance gradually returns to the original air atmosphere resistance level.

[0061] Figure 3 At room temperature operating temperature, using Figure 9 A scatter plot of the response values ​​of the hydrogen sensor based on 14Pd-MoS2 sensitive material in Example 1 under hydrogen atmospheres of 150, 300, 1000, 5000, 10000, and 15000 ppm using a gas dynamic testing system. Figure 3 It can be seen that the response values ​​of the hydrogen sensor based on 14Pd-MoS2 sensitive material in Example 1 are 2.94, 3.34, 5.12, 8.22, 10.49, and 13.27 in hydrogen atmospheres of 150, 300, 1000, 5000, 10000, and 15000 ppm, respectively. The higher the concentration of hydrogen introduced at room temperature, the higher the response value of the hydrogen sensor based on 14Pd-MoS2 sensitive material.

[0062] Figure 4 The following are the continuous response graphs of hydrogen sensors based on 10Pd-MoS2-O sensing material in Comparative Example 2 (a) at 1000, 5000, and 10000 ppm hydrogen atmospheres; and the following are the continuous response graphs of hydrogen sensors based on 12Pd-MoS2-O, 14Pd-MoS2-O, and 16Pd-MoS2-O sensing materials in Comparative Example 4 at 1000, 5000, 10000, and 15000 ppm hydrogen atmospheres. Figure 4 It can be seen that, at room temperature, the sensor based on the 14Pd-MoS2-O sensitive material has the highest response to hydrogen among the four groups of sensors.

[0063] Figure 5 Examples a) Comparative Example 2: a hydrogen sensor based on 10Pd-MoS2-O sensitive material; b) Comparative Example 1: a hydrogen sensor based on 14Pd-MoS2-O sensitive material; and c) Example 1: a hydrogen sensor based on 14Pd-MoS2 sensitive material. The curves show the change in resistance between the interdigitated electrodes over time during a cycle of exposure to 1000 ppm hydrogen gas followed by exposure to air. Figure 5 It can be seen that the hydrogen sensor based on 14Pd-MoS2 sensitive material has the fastest response speed to 1000 ppm hydrogen at room temperature, which is essential for the rapid detection of hydrogen.

[0064] Figure 6 The figures represent the interdigital electrode resistance response values ​​of the hydrogen sensor based on 14Pd-MoS2 nanosheet sensing material in Example 1 at room temperature in atmospheres of 1000 ppm hydrogen, 10000 ppm methane, 100 ppm methanol, 100 ppm ammonia, 100 ppm CO, 20 ppm toluene, and 5 ppm H2S. Figure 6It can be seen that the hydrogen sensor based on 14Pd-MoS2 sensitive material at room temperature has a significantly higher response value for 1000 ppm hydrogen than other common interfering gases, and has good gas selectivity.

[0065] Using an ultra-deep 3D microscope with continuous optical zoom, layer-by-layer images of flexible, sensitive films are captured along the Z-axis without the need for physical slicing. The collected images can be overlaid to generate height maps, providing an intuitive understanding of the 3D surface morphology. The results are as follows: Figure 7 As shown, Figure 7 (a) shows the three-dimensional surface morphology of the hydrogen sensor sensitive film prepared by drop-coating using 14Pd-MoS2 nanosheet sensitive material in Example 1, after being bent 90° 0 times. Figure 7 Figures b) through d) show the three-dimensional surface morphology of the hydrogen sensor sensitive membrane prepared by 3D printing using 14Pd-MoS2 nanosheet sensitive material in Example 2, after 0, 30, and 90 90-degree bends. It can be seen that the flexible sensitive membrane prepared by 3D printing has better consistency and maintains a good surface morphology even after dozens of bends.

[0066] Figure 8 The graph shows the continuous response of the hydrogen sensor sensitive film, prepared by 3D printing using 14Pd-MoS2 nanosheet sensitive material based on Example 2, to hydrogen atmospheres of different concentrations (1000, 5000, 10000, and 15000 ppm) after being bent at 90° for 0, 30, and 90 times. It can be seen that the resistance and response amplitude of the flexible hydrogen sensor prepared by this method are almost negligible after 30 90° bends. After 90 90° bends, the resistance increases slightly, but it still maintains a good response to different hydrogen concentrations, demonstrating the sensor's excellent wearable characteristics.

[0067] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A molybdenum disulfide-based hydrogen-sensitive material, characterized in that, It includes two-dimensional MoS2 nanosheets and Pd loaded on the two-dimensional MoS2 nanosheets.

2. The method for preparing the molybdenum disulfide-based hydrogen-sensitive material according to claim 1, characterized in that, Includes the following steps: MoS2, sodium tartrate, and an organic solvent are mixed to obtain a mixture. The mixture was subjected to ultrasonic intercalation and then centrifuged. The supernatant was taken and dried to obtain MoS2 two-dimensional nanosheets. The dispersion of the MoS2 two-dimensional nanosheets was mixed with PdCl2 and sodium borohydride, and chemically reduced. The resulting product was then vacuum dried to obtain the molybdenum disulfide-based hydrogen-sensitive material.

3. The preparation method according to claim 2, characterized in that, The mass ratio of MoS2 to sodium tartrate is (150~200):(25~31.25).

4. The preparation method according to claim 2, characterized in that, The temperature of the mixture during the ultrasonic intercalation treatment is 15~30℃, the ultrasonic power is 350~450 W, and the ultrasonic intercalation treatment time is 3~4 h.

5. The preparation method according to claim 2, characterized in that, The mass of PdCl2 is 10-16% of the mass of MoS2 two-dimensional nanosheets in the dispersion of MoS2 two-dimensional nanosheets.

6. The preparation method according to claim 2 or 5, characterized in that, The molar ratio of sodium borohydride to PdCl2 is 1.5~2.5:1, and the chemical reduction time is 2~3 h.

7. A flexible room temperature hydrogen sensor, characterized in that, The invention comprises a flexible substrate on which interdigitated electrodes are deposited and a sensitive film covering the surface of the interdigitated electrodes, the sensitive film being formed from the molybdenum disulfide-based hydrogen sensitive material of claim 1 or the molybdenum disulfide-based hydrogen sensitive material prepared by the preparation method of any one of claims 2 to 6.

8. The method for preparing the flexible room temperature hydrogen sensor according to claim 7, characterized in that, Includes the following steps: The dispersion of the molybdenum disulfide-based hydrogen sensing material is deposited onto the surface of the interdigitated electrodes on a flexible substrate with interdigitated electrodes deposited thereon to form a sensitive film, thereby obtaining the flexible room temperature hydrogen sensor; the dispersion of the molybdenum disulfide-based hydrogen sensing material is deposited by 3D printing or coating.

9. The preparation method according to claim 8, characterized in that, When the dispersion of the molybdenum disulfide-based hydrogen-sensitive material is deposited by 3D printing, the 3D printing is performed using a vision dispensing machine, the dispensing pressure is 20~30 kPa, the temperature of the dispensing machine's flat worktable is set to 35~43℃, the frequency of the dispensing machine's piezoelectric valve is 190 Hz, the number of dispensing times is 2~3, and the concentration of the dispersion of the molybdenum disulfide-based hydrogen-sensitive material is 8~15 mg / mL; when the dispersion of the molybdenum disulfide-based hydrogen-sensitive material is deposited by coating, the concentration of the dispersion of the molybdenum disulfide-based hydrogen-sensitive material is 2~4 mg / mL.

10. The application of the flexible room temperature hydrogen sensor according to claim 7 or the flexible room temperature hydrogen sensor prepared by the preparation method according to claim 8 or 9 in monitoring ambient hydrogen.

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