A method for preparing a two-dimensional material hydrogen sensor modified by platinum-palladium dispersion

Abstract

The present invention discloses a preparation method of a hydrogen sensor based on a two-dimensional material modified by a platinum-palladium dispersion, comprising: first reducing nano-palladium particles and loading them on two-dimensional layered Ti3C2T X MXene, and then centrifuging and drying to form a Ti3C2T X MXene material modified with palladium particles. Then, reducing platinum nano-materials and loading them on the Ti3C2T X MXene material modified with palladium particles, and then centrifuging and drying to obtain a Ti3C2T X MXene hydrogen-sensitive material modified by a platinum-palladium dispersion. Finally, depositing the Ti3C2T X MXene powder modified by a platinum-palladium dispersion on interdigitated electrodes to complete the preparation of the hydrogen sensor. The present invention can be used in places such as nuclear power plants, hydrogen storage bottles, and hydrogen fuel cell vehicles to effectively detect whether hydrogen leaks.

Description

Technical Field

[0001] The invention belongs to the technical field of hydrogen sensing detection, and specifically relates to a method for preparing a two-dimensional material hydrogen sensor modified by a platinum-palladium dispersion. Background Art

[0002] At present, the energy crisis is becoming increasingly severe, and hydrogen energy is undoubtedly the most forward-looking green energy. However, the safety of hydrogen energy must not be ignored, which is a prerequisite for the application of hydrogen energy. Hydrogen leakage is the key to the safety of hydrogen energy production, storage and transportation. Since hydrogen is colorless and odorless, it is extremely difficult for humans to identify hydrogen leakage before the danger of explosion occurs. Hydrogen safety accidents are so common that people "change color when talking about hydrogen", so it is crucial to develop high-performance hydrogen sensors to avoid the danger of hydrogen leakage.

[0003] Over the years, researchers have done a lot of research on the development of hydrogen sensors. Invention patent CN101968461A discloses a miniature hydrogen sensor, the hydrogen-sensitive material of which is palladium-nano tin dioxide film, which is a precious metal such as palladium doped with tin dioxide to improve sensitivity, reduce response time, and reduce operating temperature. Utility model patent CN204514848U discloses a high-performance hydrogen sensor with a Si / SiO2 / graphene / palladium multilayer structure, which has high sensitivity and fast response time in low-concentration hydrogen detection. Invention patent CN107024507A discloses a hydrogen sensor of a porous composite film of titanium oxide and palladium, which includes anodized aluminum oxide, a porous titanium oxide film, a porous metal palladium film and two metal electrodes from bottom to top. The porous titanium oxide film can effectively improve the hydrogen absorption performance of the metal palladium film, reduce the response time of the hydrogen sensor, and improve the responsiveness of the hydrogen sensor. The titanium oxide film layer also ensures the selectivity of the device. Invention patent CN112782153A discloses a tungsten trioxide-palladium-platinum composite nano-thin film optical fiber hydrogen sensor. The optical fiber hydrogen sensor has a certain intrinsic safety, but the high price and complex operation are currently difficult to solve problems.

[0004] However, the hydrogen sensors currently developed cannot detect hydrogen leaks in a timely and effective manner. This is not only reflected in the sensitivity and response speed of hydrogen detection, but also in the life and reliability of hydrogen sensors. In view of this, the plan clearly puts forward the issue of hydrogen safety prevention and control, focusing on the development of fast, sensitive, low-cost hydrogen sensors and hydrogen micro-leakage monitoring materials. Therefore, the development of high-performance hydrogen sensors is a long and arduous task. Summary of the invention

[0005] An object of the present invention is to solve at least the above problems and to provide at least the advantages which will be described hereinafter.

[0006] In view of the problems of low detection sensitivity and long response time of the current sensing materials that can be used for hydrogen leak detection at room temperature, the present invention proposes a preparation method and application of a two-dimensional material hydrogen sensor modified by platinum-palladium dispersion, which can effectively solve the above-mentioned problems.

[0007] The present invention develops a method for preparing a two-dimensional material hydrogen sensor modified by platinum-palladium dispersion. The preparation method first reduces nano-palladium particles and loads them on a two-dimensional layered Ti3C2T X MXene, and then centrifuged and dried to form palladium particle-modified Ti3C2T X MXene materials, and then reducing platinum nanomaterials and loading them on palladium particle-modified Ti3C2T X MXene material, centrifuged and dried to obtain Ti3C2T modified by PtPd dispersion X MXene hydrogen-sensitive material, finally Ti3C2T modified by PtPd dispersion X MXene powder is deposited on the interdigitated electrodes to complete the preparation of the hydrogen sensor.

[0008] In order to achieve these purposes and other advantages of the present invention, a method for preparing a two-dimensional material hydrogen sensor modified with platinum-palladium dispersion is provided, wherein Ti3C2T X MXene-loaded platinum-palladium dispersion is used as a key material of the sensor for hydrogen leak detection; wherein the preparation method of the hydrogen sensor based on the modification of the platinum-palladium dispersion comprises the following steps:

[0009] Step 1, adding polyvinyl alcohol to the PdCl2 solution in proportion to obtain a first solution;

[0010] Step 2, adding NaBH4 solution dropwise into the first solution according to a certain proportion to react and obtain a second solution;

[0011] Step 3: Proportionally mix Ti3C2T X The MXene powder was dissolved in the second solution, centrifuged, filtered and dried to obtain Pd / Ti3C2T X MXene powder;

[0012] Step 4: adding polyvinyl alcohol to the H2PtCl6·6H2O solution in proportion to obtain a third solution;

[0013] Step 5, adding NaBH4 solution dropwise into the third solution in proportion to react, to obtain a fourth solution;

[0014] Step 6: Pd / Ti3C2T XMXene powder was added to the fourth solution, centrifuged, filtered, and dried to obtain Pt=Pd / Ti3C2T X MXene powder;

[0015] Step 7: Pt=Pd / Ti3C2T X MXene powder was dissolved and dripped on the interdigital electrodes, and after drying, Ti3C2T modified with PtPd dispersion was obtained. X MXene room temperature hydrogen sensor.

[0016] Preferably, in the step 1, the PdCl2 powder is ultrasonically dispersed in deionized water to obtain the PdCl2 solution, and the concentration of the PdCl2 solution is 0.001 to 0.005 M;

[0017] The first solution is obtained by ultrasonically dispersing polyvinyl alcohol in a PdCl2 solution, wherein the mass ratio of polyvinyl alcohol to PdCl2 powder in the first solution is 1 to 5:1.

[0018] Preferably, in the step 2, a NaBH4 solution with a concentration of 0.003 g / mL is prepared, the mass ratio of the NaBH4 solution to the PdCl2 powder is 1 to 5:1, and the NaBH4 solution is slowly added dropwise to the first solution using a 0.5 to 1 mL pipette, and the reaction is carried out under magnetic stirring conditions for 60 to 120 minutes to obtain the second solution.

[0019] Preferably, in step 2, the magnetic stirring speed is 800-1500 rpm, and the magnetic stirring temperature is 30-50°C.

[0020] Preferably, in step 3, the PdCl2 powder and Ti3C2T X The mass ratio of MXene powder is 1:10-15, and Ti3C2T X MXene powder is added to the second solution and magnetically stirred for 30 to 90 minutes before being taken out for centrifugation. The liquid after centrifugation is vacuum filtered to complete the Pd particle-modified Ti3C2T X The MXene powder was prepared and finally dried in a vacuum oven for 16 to 20 hours.

[0021] Preferably, in step 3, Ti3C2T X MXene is used as a carrier to solidify Pd particles on Ti3C2T X The MXene surface was washed alternately 3 to 6 times with anhydrous ethanol, deionized water and acetone during centrifugation, wherein the speed of the centrifuge was 8000 to 12000 rpm, a 0.22 um cellulose membrane was used for vacuum filtration, and the vacuum drying temperature was 100 to 120 °C.

[0022] Preferably, in the step 4, 0.02 g / mL of H2PtCl6·6H2O solution is added to deionized water, magnetically stirred and ultrasonically treated for 1 to 5 minutes; the volume ratio of H2PtCl6·6H2O solution to deionized water is 1 to 3:140; the ultrasonic dispersion time is 10 to 30 minutes, the ultrasonic temperature is 25 to 60°C, the ultrasonic power is 54w, and the magnetic stirring speed is 800 to 1500rpm;

[0023] According to the mass ratio of polyvinyl alcohol to H2PtCl6·6H2O being 1 to 5:1, polyvinyl alcohol is added to the H2PtCl6·6H2O solution, and ultrasonic dispersion is performed until the polyvinyl alcohol powder is completely dissolved in the H2PtCl6·6H2O solution. The ultrasonic dispersion time is 1 to 10 minutes, the ultrasonic temperature is 25 to 60°C, the ultrasonic power is 54W, and the magnetic stirring speed is 800 to 1500rpm.

[0024] Preferably, in the step five, a NaBH4 solution with a concentration of 0.003 g / mL is prepared, and the NaBH4 solution is added dropwise to the third solution using a 0.5-1 mL pipette for reaction for 60-120 minutes, and magnetic stirring is performed, and the mass ratio of the NaBH4 solution to the H2PtCl6·6H2O powder is 1-5:1.

[0025] Preferably, in step six, Pd / Ti3C2T X MXene powder was added to the fourth solution, and after magnetic stirring for 30 to 90 minutes, the solution was taken out and centrifuged at high speed. X MXene as a carrier, Pd particles and Pt particles solidified on Ti3C2T X The MXene surface was washed alternately with anhydrous ethanol, deionized water and acetone for 3 to 6 times during high-speed centrifugation. The liquid after centrifugation was vacuum filtered to complete the Ti3C2T modified with PtPd dispersion. X Preparation of MXene powder, and finally drying in a vacuum oven for 16 to 20 hours; Pd / Ti3C2T X The mass ratio of the MXene powder to the H2PtCl6·6H2O powder in the fourth solution is 10 to 15:1.

[0026] The rotation speed of the centrifuge is 8000-12000 rpm, a 0.22 um cellulose membrane is used for vacuum filtration, and the temperature of vacuum drying is 100-120°C.

[0027] Preferably, in step 7, Pt=Pd / Ti3C2T XThe mass concentration percentage of MXene is 10-30%; after ultrasonic dispersion, use a pipette to transfer Pt=Pd / Ti3C2T X MXene liquid is dropped on the interdigital electrodes, the ultrasonic dispersion time is 2 to 5 minutes, the ultrasonic temperature is 25 to 60°C, and the ultrasonic power is 54w. After the dropwise addition is completed, the interdigital electrodes are placed in a drying oven for 2 to 5 hours to solidify the liquid on the interdigital electrodes. The drying temperature is 60 to 80°C. The electrode material of the interdigital electrodes is Cu / Au / Ni.

[0028] The present invention has at least the following beneficial effects:

[0029] 1. This patent invents a method for preparing a two-dimensional material hydrogen sensor modified by platinum-palladium dispersion. The platinum-palladium dispersion modified Ti3C2T X MXene has ultra-high hydrogen response and stability, and can perform highly sensitive hydrogen leak detection at room temperature, which can effectively determine the hydrogen leakage situation.

[0030] 2. Ti3C2T modified by platinum-palladium dispersion of the present invention X MXene materials can be directly applied in fields such as sensing. X MXene materials can be made into different types of sensors and used in nuclear power plants, hydrogen storage bottles, hydrogen fuel cell vehicles and other places to effectively detect hydrogen leaks.

[0031] Other advantages, objectives and features of the present invention will be embodied in part through the following description, and in part will be understood by those skilled in the art through study and practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is Ti3C2T modified by PtPd dispersion X XRD pattern of MXene;

[0033] Figure 2 It is Ti3C2T modified by PtPd dispersion X TEM morphology of MXene;

[0034] Figure 3 It is Ti3C2T modified by PtPd dispersion X HRTEM morphology of MXene;

[0035] Figure 4 It is Ti3C2T modified by PtPd dispersion X HRTEM magnified morphology of MXene;

[0036] Figure 5 It is Ti3C2T modified by PtPd dispersionX XPS spectrum of MXene;

[0037] Figure 6 It is Ti3C2T modified by PtPd dispersion X Response of MXene to different hydrogen concentrations;

[0038] Figure 7 In the embodiment, Ti3C2T X SEM morphology of MXene 1;

[0039] Figure 8 In the embodiment, Ti3C2T X SEM morphology of MXene 2;

[0040] Fig. 9 yes Figure 2 and Figure 4 Comparison analysis diagram of

[0041] Fig.10 This is a comparison of the hydrogen sensing responses exhibited by different platinum-palladium structures. DETAILED DESCRIPTION

[0042] The present invention is further described in detail below in conjunction with the accompanying drawings so that those skilled in the art can implement the invention with reference to the description.

[0043] It should be understood that terms such as “having”, “including” and “comprising” used in this patent do not specify the existence or addition of one or more other elements or combinations thereof.

[0044] This patent prepares a platinum-palladium dispersion bimetallic catalyst by chemical reduction and loads it on the surface of MXenes with metallic conductivity and large specific surface area. The prepared platinum-palladium dispersion modified Ti3C2T X MXene materials have ultra-high hydrogen sensing performance, including high sensitivity, short response and recovery time, high repeatability, low concentration hydrogen detection limit, high reversibility and low hysteresis.

[0045] Ti3C2T modified by platinum-palladium dispersion of the present invention X MXene materials have the characteristics of large specific surface area, high stability and high response speed, which can promptly feedback hydrogen leakage information to technicians and deal with leakage problems in a timely manner.

[0046] The carrier in the method of the present invention is Ti3C2T X In addition to MXene, including but not limited to: V2CT X MXene, Ti3CNT XMXene, TiVC MXene, Nb2C MXene, graphene, graphene oxide, reduced graphene oxide, molybdenum sulfide and other two-dimensional layered nanomaterials. In order to facilitate the test of the hydrogen leakage detection effect of the material of the present invention, this embodiment uses Ti3C2T X MXene, designed Ti3C2T modified by PtPd dispersion X Preparation and performance testing of MXene hydrogen sensors.

[0047] Ti3C2T X The preparation method of MXene can be found in the relevant patents: CN110304632A, Lamellar MXene material and its preparation method and energy storage material; CN111268681A, A MXene material and its preparation method and application. X The morphology of MXene materials can be seen in Figure 7-8 shown.

[0048] Ti3C2T X Characteristics and advantages of MXene:

[0049] Ti3C2T X MXene is a layered two-dimensional nanomaterial that is shaped like an accordion. It has high electron mobility and therefore metallic conductivity. It also has a large specific surface area, making it easy to disperse and load platinum and palladium particles. X The surface of MXene has a large number of gas adsorption sites, which makes it easy for gas molecules to diffuse, adsorb, and desorb.

[0050] Example

[0051] Ti3C2T modified by PtPd dispersion X Preparation of MXene hydrogen sensor:

[0052] PdCl2 was used as the precursor salt of palladium, H2PtCl6·6H2O was used as the precursor salt of platinum, polyvinyl alcohol (PEG) was used as the dispersant, deionized water was used as the solvent, NaBH4 was used as the reducing agent, Ti3C2T X MXene as a carrier to prepare Pt-Pd dispersion modified Ti3C2T X MXene.

[0053] The reaction process involved is as follows:

[0054] Palladium chloride reacts with sodium borohydride: Pd 2+ +2BH4 - =Pd↓+B2H6+H2↑

[0055] Reaction of chloroplatinic acid hydrate with sodium borohydride: PtCl6 2- +BH4 - +3H2O=Pt↓+H3BO3+2H2↑+3H + +6Cl -

[0056] First, 140 mL of deionized water was measured in a 500 mL flat-bottom flask, 40 mg of PdCl2 powder was added first, and then a certain amount of polyvinyl alcohol was added, wherein the mass ratio of the total amount of precious metal to polyvinyl alcohol was 1:1. After stirring evenly, 10 mL of NaBH4 solution with a concentration of 0.003 g / mL was added dropwise with a pipette (1 mL), and the mixture was stirred vigorously and reacted for 60 minutes.

[0057] After the reaction is complete, add 0.5 g Ti3C2T X MXene powder, after curing for 30 minutes, the mixed solution was taken out into a centrifuge tube (100 mL) for high-speed centrifugation at a speed of 12000 rpm for 10 minutes. At the same time, deionized water, anhydrous ethanol and acetone were used for alternating centrifugation and washing 5 times. After the centrifugation treatment, the solid powder was placed in a vacuum drying oven at 110 ° C and dried for 16 hours.

[0058] At this point, the Ti3C2T modified with Pd particles is completed. X Preparation of MXene powder. Similarly, 140 mL of deionized water was measured in a 500 mL flat-bottom flask, and 2 mL of H2PtCl6·6H2O solution with a concentration of 0.02 g / mL was added first, and then a certain amount of polyvinyl alcohol was added, wherein the mass ratio of the total amount of precious metal to polyvinyl alcohol was 1:1, and after stirring evenly, 10 mL of NaBH4 solution with a concentration of 0.003 g / mL was added dropwise with a pipette (1 mL), and the mixture was stirred vigorously and reacted for 60 minutes.

[0059] After the reaction is complete, the Ti3C2T modified with Pd particles prepared previously is added to the above solution. X MXene powder, after curing for 30 minutes, take out the mixed solution into a centrifuge tube (100mL) for high-speed centrifugation. The speed of the centrifuge is 12000rpm, and the centrifugation time is 10 minutes. At the same time, deionized water, anhydrous ethanol and acetone are alternately centrifuged and washed 5 times. After the centrifugation is completed, the solid powder is placed in a 110℃ vacuum drying oven for 16 hours. After drying, a small amount of powder is dissolved in deionized water, and the solution is dripped on the Cu / Au / Ni interdigital electrode based on alumina, and finally placed in a 60℃ drying oven for 180 minutes to complete the platinum-palladium dispersion modified Ti3C2T X Preparation of MXene hydrogen sensor.

[0060] Figure 1 Ti3C2T modified by PtPd dispersion X XRD spectrum of MXene. It can be seen from the figure that the Pt-Pd dispersion corresponds to the (111), (200) and (220) crystal planes, and Ti3C2T X MXene corresponds to the (002) crystal plane;

[0061] Figure 2 It is Ti3C2T modified by PtPd dispersion X TEM morphology of MXene. It can be clearly seen from the figure that palladium particles and platinum clusters are evenly distributed in the layered Ti3C2T X MXene surface;

[0062] Figure 3 and Figure 4 They are Ti3C2T modified by Pt-Pd dispersions. X HRTEM morphology of MXene and high-resolution lattice magnification of palladium-platinum dispersion. From the lattice spacing in the figure, it can be concluded that the lattice spacing of platinum-palladium dispersion is Corresponding to the (111) crystal plane, Ti3C2T X The lattice spacing of MXene is Corresponding to (0110) crystal plane;

[0063] Figure 5 It is Ti3C2T modified by PtPd dispersion X The XPS spectrum of MXene shows the presence of C, Ti, Pt and Pd, which further proves the Ti3C2T modified by PtPd dispersion. X Successful preparation of MXene.

[0064] Fig. 9 The middle is a two-dimensional layered Ti3C2T X TEM morphology of Pd particles and Pt clusters loaded on MXene. It can be seen from the figure that Pd particles and Pt clusters are dispersed in the two-dimensional layered Ti3C2T X On MXene, the size of Pd particles is about 2nm, and the size of Pt clusters is about 20nm. The inserted enlarged image is the HRTEM image of Pd particles and Pt clusters. The lattice fringes of Pd particles and Pt clusters can be clearly seen in the image, and the lattice spacing is 0.23nm, which further confirms that Pt=Pd / Ti3C2T X Successful synthesis of MXene.

[0065] Sensor performance verification

[0066] The experimental environment temperature is 26℃ and the humidity is 67%RH. The prepared sensor electrodes are connected to the LCR digital bridge, the bridge model is UC2858B+. The experimental test is for different concentrations of hydrogen. Figure 6 As shown in the figure, the hydrogen sensor has the greatest sensitivity at a frequency of 100 Hz, the response value of the sensor reaches 95% at a hydrogen concentration of 1%, the response value of the sensor reaches 98% at a hydrogen concentration of 2%, and the response value of the sensor reaches 37% at 1 ppm. Overall, with the increase of hydrogen concentration, the response value of the sensor shows a linear increase, and has good response characteristics.

[0067] The sensor prepared by the present invention comprises Ti3C2T modified by platinum-palladium dispersion X MXene and high-sensitivity, high-response, low-concentration hydrogen detection limit, and high-stability hydrogen leak detection sensing materials, when used as sensitive materials for hydrogen leak detection sensors, can stably, promptly and effectively feedback hydrogen leak conditions to staff to avoid safety accidents.

[0068] Comparative Example 1

[0069] The difference from Example 1 is the order of the synthesis steps. Specifically, PdCl2 is used as a precursor salt of palladium, H2PtCl6·6H2O is used as a precursor salt of platinum, polyvinyl alcohol is used as a dispersant, deionized water is used as a solvent, NaBH4 is used as a reducing agent, and MXenes are used as a carrier to prepare platinum-palladium alloy-modified MXenes. 140 mL of deionized water is measured in a flat-bottomed flask with a capacity of 500 mL, 2 mL of H2PtCl6·6H2O solution with a concentration of 0.02 g / mL is added first, and then 40 mg of PdCl2 powder is added for magnetic stirring. After mixing evenly, a certain amount of polyvinyl alcohol is added, wherein the mass ratio of the total amount of precious metal to polyvinyl alcohol is 1:1, and after stirring evenly again, 20 mL of NaBH4 solution with a concentration of 0.003 g / mL is added dropwise with a pipette (1 mL), and vigorously stirred and reacted for 60 minutes. After the reaction is complete, add 0.5g of MXenes powder to the above solution. After curing for 30 minutes, take out the mixed solution and put it into a centrifuge tube (100mL) for high-speed centrifugation. The speed of the centrifuge is 8000rpm, and the centrifugation time is 10 minutes. At the same time, use deionized water and anhydrous ethanol to alternately centrifuge and wash twice. After the centrifugation is completed, the solid powder is placed in a 110°C vacuum drying oven and dried for 16 hours. After drying, take a small amount of powder and dissolve it in deionized water, and add the solution dropwise on the Cu / Au interdigital electrode based on alumina, and finally place it in a 60°C drying oven for 60 minutes to complete the preparation of the platinum-palladium alloy modified MXenes hydrogen sensor.

[0070] Comparative Example 2

[0071] The difference from Example 1 is the order of the synthesis steps. Specifically, PdCl2 is used as a precursor salt of palladium, H2PtCl6·6H2O is used as a precursor salt of platinum, polyvinyl alcohol is used as a dispersant, deionized water is used as a solvent, NaBH4 is used as a reducing agent, and MXenes are used as a carrier to prepare platinum-palladium core-shell modified MXenes. 70 mL of deionized water was measured in a flat-bottomed flask with a capacity of 300 mL, 40 mg of PdCl2 powder was added first, and then a certain amount of polyvinyl alcohol was added, wherein the mass ratio of the total amount of precious metal to polyvinyl alcohol was 1:1, and after stirring evenly, 10 mL of NaBH4 solution with a concentration of 0.003 g / mL was added dropwise with a pipette (1 mL), and vigorously stirred and reacted for 60 minutes. Similarly, take another flat-bottom flask with a capacity of 300 mL, measure 70 mL of deionized water and inject it into it, first add 2 mL of H2PtCl6·6H2O solution with a concentration of 0.02 g / mL, and then add a certain amount of polyvinyl alcohol, wherein the mass ratio of the total amount of precious metal to polyvinyl alcohol is 1:1, stir evenly, and then add 10 mL of NaBH4 solution with a concentration of 0.003 g / mL dropwise with a pipette (1 mL), and stir vigorously and react for 60 minutes.

[0072] After the two reactions are complete, the above solutions are added to a flat-bottom flask with a capacity of 500mL at the same time. After magnetic stirring for 30 minutes, 0.5g of MXenes powder is added to the above solution. After curing for 30 minutes, the mixed solution is taken out to a centrifuge tube (100mL) for high-speed centrifugation. The speed of the centrifuge is 8000rpm, and the centrifugation time is 10 minutes. At the same time, deionized water and anhydrous ethanol are used for alternating centrifugation and washing twice. After the centrifugation treatment is completed, the solid powder is placed in a vacuum drying oven at 110℃ and dried for 16 hours. After drying, a small amount of powder is dissolved in deionized water, and the solution is dripped on the Cu / Au interdigital electrode based on alumina, and finally placed in a 60℃ drying oven for curing for 60 minutes to complete the preparation of the platinum-palladium core-shell modified MXenes hydrogen sensor.

[0073] Fig.10 The two-dimensional layered Ti3C2T modified by PtPd dispersion, PtPd alloy and PtPd core-shell X Response of MXene to different hydrogen concentrations, among which, two-dimensional layered Ti3C2T modified by PtPd dispersion X MXene exhibits the highest response value under various hydrogen concentrations, thereby showing the best hydrogen sensing performance. Therefore, it is concluded that the hydrogen sensor prepared by the technical solution of the present invention has the best performance.

[0074] As described above, this patent invents a method for preparing a two-dimensional material hydrogen sensor modified by a platinum-palladium dispersion. The platinum-palladium dispersion modified Ti3C2T XMXene materials have a large specific surface area and excellent stability, and can perform highly sensitive hydrogen leakage detection at room temperature, and can effectively and reliably obtain hydrogen leakage information. X MXene materials can be directly applied in fields such as sensing. X MXene materials can be made into different types of sensors and used in nuclear power plants, hydrogen storage bottles, hydrogen fuel cell vehicles and other places to effectively detect hydrogen leaks.

[0075] Although the embodiments of the present invention have been disclosed as above, they are not limited to the applications listed in the specification and the implementation modes, and they can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to the specific details and the illustrations shown and described herein.

Claims

1. A method for preparing a two-dimensional material hydrogen sensor modified by platinum-palladium dispersion, characterized in that: The following steps are involved: Step 1, adding polyvinyl alcohol to the PdCl2 solution in proportion to obtain a first solution; Step 2, adding NaBH4 solution dropwise into the first solution according to a certain proportion to react and obtain a second solution; Step 3: Proportionally mix Ti3C2T X The MXene powder was dissolved in the second solution, centrifuged, filtered and dried to obtain Pd / Ti3C2T X MXene powder; Step 4: adding polyvinyl alcohol to the H2PtCl6·6H2O solution in proportion to obtain a third solution; Step 5, adding NaBH4 solution dropwise into the third solution in proportion to react, to obtain a fourth solution; Step 6: Pd / Ti3C2T X MXene powder was added to the fourth solution, centrifuged, filtered, and dried to obtain Pt=Pd / Ti3C2T X MXene powder; Step 7: Pt=Pd / Ti3C2T X MXene powder was dissolved and dripped on the interdigital electrodes, and after drying, Ti3C2T modified with PtPd dispersion was obtained. X MXene room temperature hydrogen sensor.

2. The method for preparing a two-dimensional material hydrogen sensor modified by a platinum-palladium dispersion as claimed in claim 1, characterized in that: In the step 1, the PdCl2 powder is ultrasonically dispersed in deionized water to obtain the PdCl2 solution, wherein the concentration of the PdCl2 solution is 0.001 to 0.005 M; The first solution is obtained by ultrasonically dispersing polyvinyl alcohol in a PdCl2 solution, wherein the mass ratio of polyvinyl alcohol to PdCl2 powder in the first solution is 1 to 5:

1.

3. The method for preparing a two-dimensional material hydrogen sensor modified by a platinum-palladium dispersion as claimed in claim 2, characterized in that: In the step 2, a NaBH4 solution with a concentration of 0.003 g / mL is prepared, the mass ratio of the NaBH4 solution to the PdCl2 powder is 1 to 5:1, and the NaBH4 solution is slowly added dropwise to the first solution using a 0.5 to 1 mL pipette, and the reaction is carried out under magnetic stirring conditions for 60 to 120 minutes to obtain the second solution.

4. The method for preparing a two-dimensional material hydrogen sensor modified by a platinum-palladium dispersion as claimed in claim 3, characterized in that: In the step 2, the magnetic stirring speed is 800-1500 rpm, and the magnetic stirring temperature is 30-50°C.

5. The method for preparing a two-dimensional material hydrogen sensor modified by a platinum-palladium dispersion as claimed in claim 4, characterized in that: In the step 3, according to the PdCl2 powder and Ti3C2T X The mass ratio of MXene powder is 1:10-15, and Ti3C2T X MXene powder is added to the second solution and magnetically stirred for 30 to 90 minutes before being taken out for centrifugation. The liquid after centrifugation is vacuum filtered to complete the Pd particle-modified Ti3C2T X The MXene powder was prepared and finally dried in a vacuum drying oven for 16 to 20 hours.

6. The method for preparing a two-dimensional material hydrogen sensor modified by a platinum-palladium dispersion as claimed in claim 5, characterized in that: In step 3, Ti3C2T X MXene is used as a carrier to solidify Pd particles on Ti3C2T X The MXene surface was washed alternately 3 to 6 times with anhydrous ethanol, deionized water and acetone during centrifugation, wherein the speed of the centrifuge was 8000 to 12000 rpm, a 0.22 μm cellulose membrane was used for vacuum filtration, and the vacuum drying temperature was 100 to 120 °C.

7. The method for preparing a two-dimensional material hydrogen sensor modified by a platinum-palladium dispersion as claimed in claim 6, characterized in that: In the step 4, 0.02 g / mL of H2PtCl6·6H2O solution is added to deionized water, magnetically stirred and ultrasonically treated for 1 to 5 minutes; the volume ratio of H2PtCl6·6H2O solution to deionized water is 1 to 3:140; the ultrasonic dispersion time is 10 to 30 minutes, the ultrasonic temperature is 25 to 60°C, the ultrasonic power is 54w, and the magnetic stirring speed is 800 to 1500rpm; According to the mass ratio of polyvinyl alcohol to H2PtCl6·6H2O being 1 to 5:1, polyvinyl alcohol is added to the H2PtCl6·6H2O solution, and ultrasonic dispersion is performed until the polyvinyl alcohol powder is completely dissolved in the H2PtCl6·6H2O solution. The ultrasonic dispersion time is 1 to 10 minutes, the ultrasonic temperature is 25 to 60°C, the ultrasonic power is 54W, and the magnetic stirring speed is 800 to 1500rpm.

8. The method for preparing a two-dimensional material hydrogen sensor modified by a platinum-palladium dispersion as claimed in claim 7, characterized in that: In the step 5, a NaBH4 solution with a concentration of 0.003 g / mL is prepared, and the NaBH4 solution is added dropwise to the third solution using a 0.5-1 mL pipette for reaction for 60-120 minutes, and magnetic stirring is performed. The mass ratio of the NaBH4 solution to the H2PtCl6·6H2O powder is 1-5:

1.

9. The method for preparing a two-dimensional material hydrogen sensor modified by a platinum-palladium dispersion as claimed in claim 8, characterized in that: In step 6, Pd / Ti3C2T X MXene powder was added to the fourth solution, and after magnetic stirring for 30 to 90 minutes, the solution was taken out and centrifuged at high speed. X MXene as a carrier, Pd particles and Pt particles solidified on Ti3C2T X The MXene surface was washed alternately with anhydrous ethanol, deionized water and acetone for 3 to 6 times during high-speed centrifugation. The liquid after centrifugation was vacuum filtered to complete the Ti3C2T modified with PtPd dispersion. X Preparation of MXene powder, and finally drying in a vacuum oven for 16 to 20 hours; Pd / Ti3C2T X The mass ratio of MXene powder to H2PtCl6·6H2O powder in the fourth solution is 10-15:1; The rotation speed of the centrifuge is 8000-12000 rpm, a 0.22 μm cellulose membrane is used for vacuum filtration, and the temperature of vacuum drying is 100-120° C.

10. The method for preparing a two-dimensional material hydrogen sensor modified by a platinum-palladium dispersion according to claim 9, characterized in that: In step 7, Pt=Pd / Ti3C2T X The mass concentration percentage of MXene is 10-30%; after ultrasonic dispersion, use a pipette to transfer Pt=Pd / Ti3C2T X MXene liquid is dropped on the interdigital electrodes, the ultrasonic dispersion time is 2 to 5 minutes, the ultrasonic temperature is 25 to 60°C, and the ultrasonic power is 54w. After the dropwise addition is completed, the interdigital electrodes are placed in a drying oven for 2 to 5 hours to solidify the liquid on the interdigital electrodes. The drying temperature is 60 to 80°C. The electrode material of the interdigital electrodes is Cu / Au / Ni.

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