Bimetal Ag and Pd loaded WO3 material and preparation method thereof

Abstract

The invention discloses a bimetallic Ag and Pd loaded WO3 material and a preparation method thereof, and relates to the technical field of sensor material preparation, and the preparation method comprises the following steps: 1, dissolving a tungsten source in an ethanol solution, mixing, hydrolyzing, aging, precipitating, washing, drying, calcining and cooling; 2, adding deionized water, adding a silver source solution and a palladium source, adding ascorbic acid, and stirring; 3, centrifuging, washing with ethanol and deionized water, and drying; 4, selecting a gold interdigital electrode with aluminum oxide ceramic as a substrate as a base electrode material, dipping the WO3 nano-particle dispersion liquid by using a line drawing pen, and uniformly coating the WO3 nano-particle dispersion liquid on the surface of the interdigital electrode; and 5, electrode drying and heat treatment. The efficient gas sensing material is prepared through the preparation method which is easy to operate, environmentally friendly and economical, and the gas sensing material has the advantages of being high in sensitivity, rapid in response, good in selectivity and the like at the low working temperature.

Description

Technical Field

[0001] The invention relates to the technical field of sensor material preparation, and in particular to a bimetallic Ag and Pd loaded WO3 material and a preparation method thereof. Background Art

[0002] With the tremendous progress of industry and technology, a large amount of energy is being consumed continuously, and the content of toxic and harmful gases in the air is increasing, posing a serious threat to the atmospheric environment. On the one hand, the emission of toxic gases such as nitrogen oxides and sulfur oxides in industrial waste gas can easily form a greenhouse effect, acid rain, etc. On the other hand, inhalation of these toxic gases at too high a concentration can cause poisoning, and even worse, explosions and other accidents can occur, causing huge losses to people's lives and property. Therefore, it is necessary to monitor these gases in real time and accurately. Gas sensors have been widely used due to their small size, low cost, accurate detection, and timely detection. Among the many gas sensor materials, transition metal oxides have received widespread attention due to their good chemical stability and thermal stability.

[0003] Tungsten trioxide (WO3) is a common n-type wide bandgap semiconductor material with a transition state, with a bandgap width of about 2.6 to 2.8 eV. As a wide bandgap metal oxide semiconductor, its unique hierarchical structure has a large surface area that can fully contact and react with gas molecules, and is a material that is very promising for modification into a high-performance gas sensor. WO3 has been favored by researchers due to its unique physical and chemical properties. Products containing WO3 are widely used as electrodes in gas sensors, humidity sensors, photocatalysis and other fields. WO3 materials have become one of the most promising gas-sensitive materials. However, the sensitivity, selectivity and stability of gas sensors made of pure WO3 materials are poor and cannot meet the requirements of practical applications. Therefore, it is necessary to modify WO3 by means of doping, compounding, etc. to improve its sensing performance. However, the existing WO3 modification synthesis process is complex, the conditions are harsh, and the cost is high. It is still a challenge to achieve high sensitivity and high selectivity detection of low-concentration gases at low temperatures. Summary of the invention

[0004] The object of the present invention is to provide a bimetallic Ag and Pd loaded WO3 material and a preparation method thereof, so as to solve the problems raised in the above background technology.

[0005] To achieve the above object, the present invention provides the following technical solution: a method for preparing a bimetallic Ag and Pd loaded WO3 material, comprising the following steps:

[0006] Step 1: Preparation of WO3 nanoparticles: dissolve the tungsten source in an ethanol solution, mix the solution evenly by ultrasonication, age the obtained solution after hydrolysis, and finally precipitate a blue-green precipitate; filter the precipitate after aging, rinse it with ethanol, dry it, and finally calcine the sample in a tube furnace, and obtain the WO3 nanoparticle material after cooling;

[0007] Step 2: Loading Ag and Pd ions: Add WO3 nanoparticle powder to deionized water, add silver source solution and palladium source after ultrasonic stirring, and add antioxidant and stir to obtain a redox solution;

[0008] Step 3: Post-treatment: the obtained solution is transferred to a centrifuge tube, the product is collected after centrifugation, and finally washed with ethanol and deionized water and dried to obtain WO3 nanoparticle material loaded with Ag and Pd;

[0009] Step 4: Electrode coating: A gold interdigital electrode with alumina ceramic as the substrate is selected as the base electrode material, the WO3 nanoparticles prepared in step 3 are dispersed in an ethanol solution, a surfactant is added after ultrasonic stirring to form a WO3 nanoparticle dispersion, and the suspension is dipped with a hook pen and evenly coated on the interdigital electrode;

[0010] Step 5: The electrode coated with WO3 nanoparticles is placed in a drying oven or dried naturally at room temperature, and the dried electrode is heat treated.

[0011] Preferably, in step 1, the tungsten source is selected from one or more of tungsten hexachloride, tungstic acid, and ammonium tungstate.

[0012] Preferably, the ultrasonic mixing time in step 1 is 30 minutes, and the solution changes from yellow to orange and then to green during the hydrolysis process; the obtained solution is aged, and the solution gradually changes to dark green and then to black, and finally a blue-green precipitate gradually precipitates.

[0013] Preferably, the solution is aged at a temperature of 30° C. for 48 hours.

[0014] Preferably, in step 1, the calcination temperature in the tubular furnace is 500° C. to 600° C., and the calcination time is 2 h to 3 h.

[0015] Preferably, in step 2, the silver source is a silver nitrate solution, and the palladium source is one of palladium nitrate and palladium chloride.

[0016] Preferably, in the step 2, 0.5 g of WO3 nanoparticle powder is added to 10 ml of deionized water, and after ultrasonication for 20 min, a silver source solution and a palladium source are added, and after adding sodium hygrosulfate, stirring is performed at 80° C. for 40 min. The concentration of the silver source is 0.001 mol / L, and the amount added is 0.001 to 29.5 ml. The amount of the palladium source added is 0.001 to 0.0053 mg.

[0017] Preferably, in the step 4, the substrate interdigital electrode is fixed, and the WO3 nanoparticle dispersion is dipped with a liner pen and evenly coated on the surface of the interdigital electrode.

[0018] The present invention also provides a bimetallic Ag and Pd loaded WO3 material, wherein the bimetallic Ag and Pd loaded WO3 material is prepared by adopting the preparation method of the Ag and Pd loaded WO3 nanoparticle material.

[0019] Preferably, based on the Ag and Pd loaded WO3 nanoparticle material, the mass percentage of Ag in the Ag and Pd loaded WO3 nanoparticle material is 0.001% to 2.00%, and the mass percentage of Pd in ​​the Ag and Pd loaded WO3 nanoparticle material is 0.001% to 2.00%.

[0020] Technical effects and advantages of the present invention:

[0021] (1) The present invention adopts a hydrolysis method to prepare WO3 material, and dopes Ag and Pd into the WO3 material by an impregnation method to synthesize WO3 nanomaterials loaded with Ag and Pd. The WO3 material loaded with Ag and Pd metals has the characteristics of small particle size, large specific surface area, high surface energy, many active sites, strong adsorption capacity, etc., which can promote the chemical reaction between the WO3 material and the gas to be measured and improve the sensitivity of the device. In addition, the precious metal can be used as a catalyst on the surface of the carrier to increase oxygen vacancies, change the size of the band gap, generate defects in the lattice, and reduce the potential barrier in the adsorption-desorption reaction process of the gas on the surface of the material. The electrode made by the modified WO3 material is used in the sensor to improve the electrode performance, while improving the sensing performance, and improving the selectivity and sensitivity of the gas sensor;

[0022] (2) The present invention deposits Ag and Pd on the surface of tungsten trioxide through simple and mild solution treatment, and can adjust the content of Ag and Pd nanoparticles by adjusting conditions such as solution concentration and immersion time, and prepares a WO3 nanomaterial gas sensor with high sensitivity, high selectivity and good stability by dispersing the nanoparticles on the surface of the electrode;

[0023] (3) The present invention produces a highly efficient gas sensing material through a simple, environmentally friendly and economical preparation method, which solves the shortcomings of existing gas sensor materials, such as complex synthesis process, harsh conditions, high cost, and difficulty in achieving high sensitivity and high selectivity detection of low-concentration gases at low temperatures. The present invention can exhibit the characteristics of high sensitivity, rapid response, and good selectivity for gases at lower operating temperatures. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1It is a schematic diagram of the preparation process of the present invention. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] The present invention provides Figure 1 A bimetallic Ag and Pd loaded WO3 material and a preparation method thereof are shown, comprising the following steps:

[0027] Step 1: Preparation of WO3 nanoparticles: dissolve the tungsten source in an ethanol solution, mix the solution evenly by ultrasonic mixing for 30 minutes, age the obtained solution after hydrolysis, and the solution changes from yellow to orange and then to green during the hydrolysis process; age the obtained solution, and the solution gradually changes to dark green and then to black, and finally gradually precipitates a blue-green precipitate, and the solution aging temperature is 30°C and the time is 48 hours; filter the precipitate after aging, rinse with ethanol, dry, and finally calcine the sample in a tubular furnace, the tubular furnace calcination temperature is 500°C to 600°C, the calcination time is 2h to 3h, and the WO3 nanoparticle material is obtained after cooling. The tungsten source is selected from one or more of tungsten hexachloride, tungstic acid, and ammonium tungstate.

[0028] Step 2: Loading Ag and Pd ions: Add WO3 nanoparticle powder to deionized water, add silver source solution and palladium source after ultrasonic stirring, add anti-hemolytic acid and stir to obtain a redox solution, the silver source is silver nitrate solution, the palladium source is one of palladium nitrate and palladium chloride, 0.5g WO3 nanoparticle powder is added to 10ml deionized water, ultrasonic for 20min, add silver source solution and palladium source, add anti-hemolytic acid and stir at 80℃ for 40min, the concentration of silver source is 0.001mol / L, the amount added is 0.001-29.5ml, and the amount of palladium source added is 0.001-0.0053mg;

[0029] Step 3: Post-treatment: the obtained solution is transferred to a centrifuge tube, the product is collected after centrifugation, and finally washed with ethanol and deionized water and dried to obtain WO3 nanoparticle material loaded with Ag and Pd;

[0030] Step 4: Electrode coating: A gold interdigital electrode with alumina ceramic as the substrate is selected as the base electrode material, the WO3 nanoparticles prepared in step 3 are dispersed in an ethanol solution, a surfactant is added after ultrasonic stirring to form a WO3 nanoparticle dispersion, and the suspension is dipped with a hook pen and evenly coated on the interdigital electrode;

[0031] Step 5: The electrode coated with WO3 nanoparticles is placed in a drying oven or dried naturally at room temperature to remove the solvent on the electrode surface, and the dried electrode is heat treated at a temperature between 450°C and 500°C. The heat treatment time is usually 1 to 3 hours. This heat treatment time range helps to ensure that the WO3 nanoparticle dispersion forms a thin film, is fully crystallized and has stable performance, so as to further improve the bonding strength between the WO3 nanoparticles and the base electrode and the performance of the electrode.

[0032] Embodiment 1

[0033] Preparation of WO3 nanoparticles: First, weigh 1.17g of tungsten hexachloride and dissolve it in 230ml of anhydrous ethanol. After ultrasonic mixing for 30 minutes, the tungsten hexachloride is fully dissolved. During the hydrolysis process, the solution changes from yellow to orange and then to green. After that, the dissolved solution is aged at room temperature (30°C) for 48 hours. The solution gradually turns dark green and then black, and finally gradually precipitates a blue-green precipitate. The precipitate is filtered and rinsed with ethanol. After rinsing, it is dried in a 60°C drying oven for 24 hours. Finally, the sample is calcined at 600°C in a tube furnace under air atmosphere for 3 hours and cooled to room temperature to obtain a WO3 nanoparticle sample.

[0034] Loading Ag and Pd ions: Weigh 0.2 g of the prepared WO3 nanoparticle sample and disperse it in 10 ml of deionized water. After ultrasonic stirring for 10 min, a WO3 dispersion was obtained. 0.001 ml of silver nitrate solution and 0.001 g of palladium chloride were added, and 0.006 g of ascorbic acid was added and stirred. The mixture was stirred at 80 ° C for 40 minutes to obtain a redox solution.

[0035] Post-treatment: the solution obtained in the above step was transferred to a centrifuge tube, the product was collected after centrifugation, and finally washed with ethanol and deionized water and dried to obtain a WO3 nanoparticle sample loaded with Ag and Pd, which was recorded as S1;

[0036] Electrode coating: A gold interdigitated electrode with alumina ceramic as the substrate is selected as the base electrode material, the WO3 nanoparticles prepared in step 3 are dispersed in an ethanol solution, a surfactant is added after ultrasonic stirring to form a WO3 nanoparticle dispersion, and the suspension is dipped with a hook pen and evenly coated on the interdigitated electrode;

[0037] Step 5: The electrode coated with WO3 nanoparticles is placed in a drying oven or dried naturally at room temperature to remove the solvent on the electrode surface, and the dried electrode is heat treated at a temperature between 450°C and 500°C for a time of generally 1 to 3 hours. This heat treatment time range helps to ensure that the WO3 nanoparticle dispersion forms a thin film, is fully crystallized and has stable performance, so as to further improve the binding force between the WO3 nanoparticles and the substrate electrode and the performance of the electrode. The obtained electrode product coated with WO3 nanoparticles loaded with Ag and Pd is A1.

[0038] Embodiment 2

[0039] Preparation of WO3 nanoparticles: First, weigh 1.17g of tungsten hexachloride and dissolve it in 230ml of anhydrous ethanol. After ultrasonic mixing for 30 minutes, the tungsten hexachloride is fully dissolved. During the hydrolysis process, the solution changes from yellow to orange and then to green. After that, the dissolved solution is aged at room temperature (30°C) for 48 hours. The solution gradually turns dark green and then black, and finally gradually precipitates a blue-green precipitate. The precipitate is filtered and rinsed with ethanol. After rinsing, it is dried in a 60°C drying oven for 24 hours. Finally, the sample is calcined at 600°C in a tube furnace under air atmosphere for 3 hours and cooled to room temperature to obtain a WO3 nanoparticle sample.

[0040] Loading Ag and Pd ions: Weigh 0.2 g of the prepared WO3 nanoparticle sample and disperse it in 10 ml of deionized water. After ultrasonic stirring for 10 min, a WO3 dispersion was obtained. 29.5 ml of silver nitrate solution and 0.001 mg of palladium chloride were added, and 6 mg of ascorbic acid was added and stirred. The mixture was stirred at 80 ° C for 40 minutes to obtain a redox solution.

[0041] Post-treatment: the solution obtained in the above step is transferred to a centrifuge tube, the product is collected after centrifugation, and finally washed with ethanol and deionized water and dried to obtain a WO3 nanoparticle sample loaded with Ag and Pd, which is recorded as S2;

[0042] Electrode coating: A gold interdigitated electrode with alumina ceramic as the substrate is selected as the base electrode material, the WO3 nanoparticles prepared in step 3 are dispersed in an ethanol solution, a surfactant is added after ultrasonic stirring to form a WO3 nanoparticle dispersion, and the suspension is dipped with a hook pen and evenly coated on the interdigitated electrode;

[0043] Step 5: The electrode coated with WO3 nanoparticles is placed in a drying oven or dried naturally at room temperature to remove the solvent on the electrode surface, and the dried electrode is heat treated at a temperature between 450°C and 500°C. The heat treatment time is usually 1 to 3 hours. This heat treatment time range helps to ensure that the WO3 nanoparticle dispersion forms a thin film, is fully crystallized and has stable performance, so as to further improve the binding force between the WO3 nanoparticles and the base electrode and the performance of the electrode. The obtained electrode product coated with WO3 nanoparticles loaded with Ag and Pd is A2.

[0044] Embodiment 3

[0045] Preparation of WO3 nanoparticles: First, weigh 1.17g of tungsten hexachloride and dissolve it in 230ml of anhydrous ethanol. After ultrasonic mixing for 30 minutes, the tungsten hexachloride is fully dissolved. During the hydrolysis process, the solution changes from yellow to orange and then to green. After that, the dissolved solution is aged at room temperature (30°C) for 48 hours. The solution gradually turns dark green and then black, and finally gradually precipitates a blue-green precipitate. The precipitate is filtered and rinsed with ethanol. After rinsing, it is dried in a 60°C drying oven for 24 hours. Finally, the sample is calcined at 600°C in a tube furnace under air atmosphere for 3 hours and cooled to room temperature to obtain a WO3 nanoparticle sample.

[0046] Loading Ag and Pd ions: Weigh 0.2 g of the prepared WO3 nanoparticle sample and disperse it in 10 ml of deionized water. After ultrasonic stirring for 10 min, a WO3 dispersion was obtained. 19.6 ml of silver nitrate solution and 1.77 mg of palladium chloride were added, and 6 mg of ascorbic acid was added and stirred. The mixture was stirred at 80 ° C for 40 minutes to obtain a redox solution.

[0047] Post-treatment: the solution obtained in the above step is transferred to a centrifuge tube, the product is collected after centrifugation, and finally washed with ethanol and deionized water and dried to obtain a WO3 nanoparticle sample loaded with Ag and Pd, which is recorded as S3;

[0048] Electrode coating: A gold interdigitated electrode with alumina ceramic as the substrate is selected as the base electrode material, the WO3 nanoparticles prepared in step 3 are dispersed in an ethanol solution, a surfactant is added after ultrasonic stirring to form a WO3 nanoparticle dispersion, and the suspension is dipped with a hook pen and evenly coated on the interdigitated electrode;

[0049] Step 5: The electrode coated with WO3 nanoparticles is placed in a drying oven or dried naturally at room temperature to remove the solvent on the electrode surface, and the dried electrode is heat treated at a temperature between 450°C and 500°C for a time of generally 1 to 3 hours. This heat treatment time range helps to ensure that the WO3 nanoparticle dispersion forms a thin film, is fully crystallized and has stable performance, so as to further improve the binding force between the WO3 nanoparticles and the substrate electrode and the performance of the electrode. The obtained electrode product coated with WO3 nanoparticles loaded with Ag and Pd is A3.

[0050] Embodiment 4

[0051] Preparation of WO3 nanoparticles: First, weigh 1.17g of tungsten hexachloride and dissolve it in 230ml of anhydrous ethanol. After ultrasonic mixing for 30 minutes, the tungsten hexachloride is fully dissolved. During the hydrolysis process, the solution changes from yellow to orange and then to green. After that, the dissolved solution is aged at room temperature (30°C) for 48 hours. The solution gradually turns dark green and then black, and finally gradually precipitates a blue-green precipitate. The precipitate is filtered and rinsed with ethanol. After rinsing, it is dried in a 60°C drying oven for 24 hours. Finally, the sample is calcined at 600°C in a tube furnace under air atmosphere for 3 hours and cooled to room temperature to obtain a WO3 nanoparticle sample.

[0052] Loading Ag and Pd ions: Weigh 0.2 g of the prepared WO3 nanoparticle sample and disperse it in 10 ml of deionized water. After ultrasonic stirring for 10 min, a WO3 dispersion was obtained. 14.7 ml of silver nitrate solution and 2.65 mg of palladium chloride were added, and 6 mg of ascorbic acid was added and stirred. The mixture was stirred at 80 ° C for 40 minutes to obtain a redox solution.

[0053] Post-treatment: the solution obtained in the above step is transferred to a centrifuge tube, the product is collected after centrifugation, and finally washed with ethanol and deionized water and dried to obtain a WO3 nanoparticle sample loaded with Ag and Pd, which is recorded as S4;

[0054] Electrode coating: A gold interdigitated electrode with alumina ceramic as the substrate is selected as the base electrode material, the WO3 nanoparticles prepared in step 3 are dispersed in an ethanol solution, a surfactant is added after ultrasonic stirring to form a WO3 nanoparticle dispersion, and the suspension is dipped with a hook pen and evenly coated on the interdigitated electrode;

[0055] Step 5: The electrode coated with WO3 nanoparticles is placed in a drying oven or dried naturally at room temperature to remove the solvent on the electrode surface, and the dried electrode is heat treated at a temperature between 450°C and 500°C for a time of generally 1 to 3 hours. This heat treatment time range helps to ensure that the WO3 nanoparticle dispersion forms a thin film, is fully crystallized and has stable performance, so as to further improve the binding force between the WO3 nanoparticles and the base electrode and the performance of the electrode. The obtained electrode product coated with WO3 nanoparticles loaded with Ag and Pd is A4.

[0056] Embodiment 5

[0057] The difference from Example 1 is that 9.83 ml of silver nitrate solution and 3.53 mg of palladium chloride are added, the synthesized Ag and Pd loaded WO3 nanoparticle sample is recorded as S5, and the prepared electrode product coated with Ag and Pd loaded WO3 nanoparticles is A5.

[0058] Example 6

[0059] The difference from Example 1 is that 0.001 ml of silver nitrate solution and 0.0053 mg of palladium chloride are added, the synthesized Ag and Pd loaded WO3 nanoparticle sample is recorded as S6, and the prepared electrode product coated with Ag and Pd loaded WO3 nanoparticles is A6.

[0060] The test results of the prepared samples are as follows

[0061]

[0062] The present invention also provides a bimetallic Ag and Pd loaded WO3 material. The bimetallic Ag and Pd loaded WO3 material is prepared by adopting the preparation method of the Ag and Pd loaded WO3 nanoparticle material.

[0063] Taking the WO3 nanoparticle material loaded with Ag and Pd as a benchmark, the mass percentage of Ag in the WO3 nanoparticle material loaded with Ag and Pd is 0.001% to 2.00%, and the mass percentage of Pd in ​​the WO3 nanoparticle material loaded with Ag and Pd is 0.001% to 2.00%.

[0064] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for preparing a bimetallic Ag and Pd loaded WO3 material, characterized in that: The following steps are involved: Step 1: Preparation of WO3 nanoparticles: dissolve the tungsten source in an ethanol solution, mix the solution evenly by ultrasonication, age the obtained solution after hydrolysis, and finally precipitate a blue-green precipitate; filter the precipitate after aging, rinse it with ethanol, dry it, and finally calcine the sample in a tube furnace, and obtain the WO3 nanoparticle material after cooling; Step 2: Loading Ag and Pd ions: Add WO3 nanoparticle powder to deionized water, add silver source solution and palladium source after ultrasonic stirring, and add antioxidant and stir to obtain a redox solution; Step 3: Post-treatment: the obtained solution is transferred to a centrifuge tube, the product is collected after centrifugation, and finally washed with ethanol and deionized water and dried to obtain WO3 nanoparticle material loaded with Ag and Pd; Step 4: Electrode coating: A gold interdigital electrode with alumina ceramic as the substrate is selected as the base electrode material, the WO3 nanoparticles prepared in step 3 are dispersed in an ethanol solution, a surfactant is added after ultrasonic stirring to form a WO3 nanoparticle dispersion, and the suspension is dipped with a hook pen and evenly coated on the interdigital electrode; Step 5: The electrode coated with WO3 nanoparticles is placed in a drying oven or dried naturally at room temperature, and the dried electrode is heat treated.

2. The method for preparing a bimetallic Ag and Pd loaded WO3 material according to claim 1, characterized in that: In the step 1, the tungsten source is selected from one or more of tungsten hexachloride, tungstic acid, and ammonium tungstate.

3. The method for preparing a bimetallic Ag and Pd loaded WO3 material according to claim 1, characterized in that: The ultrasonic mixing time in step 1 is 30 minutes, and the solution changes from yellow to orange and then to green during the hydrolysis process; the obtained solution is aged, and the solution gradually changes to dark green and then to black, and finally a blue-green precipitate gradually precipitates.

4. The method for preparing a bimetallic Ag and Pd loaded WO3 material according to claim 1, characterized in that: The solution was aged at a temperature of 30° C. for 48 h.

5. The method for preparing a bimetallic Ag and Pd loaded WO3 material according to claim 1, characterized in that: In the step 1, the calcination temperature in the tubular furnace is 500° C. to 600° C., and the calcination time is 2 h to 3 h.

6. The method for preparing a bimetallic Ag and Pd loaded WO3 material according to claim 1, characterized in that: In the step 2, the silver source is a silver nitrate solution, and the palladium source is one of palladium nitrate and palladium chloride.

7. The method for preparing a bimetallic Ag and Pd loaded WO3 material according to claim 1, characterized in that: In the step 2, 0.2 g of WO3 nanoparticle powder is added to 10 ml of deionized water, and after ultrasonication for 20 minutes, a silver source solution and a palladium source are added, and after adding sodium bicarbonate, stirring is performed at 80° C. for 40 minutes. The concentration of the silver source is 0.001 mol / L, and the amount added is 0.001 to 29.5 ml. The amount of the palladium source added is 0.001 to 0.0053 g.

8. The method for preparing a bimetallic Ag and Pd loaded WO3 material according to claim 1, characterized in that: In the step 4, the base electrode is fixed on a spin coater, and after the WO3 nanoparticle dispersion is added dropwise, the spin coater is started so that the dispersion is evenly coated on the electrode surface under the action of centrifugal force.

9. A bimetallic Ag and Pd loaded WO3 material, characterized in that: The bimetallic Ag and Pd loaded WO3 material is prepared by the preparation method of the Ag and Pd loaded WO3 nanoparticle material according to any one of claims 1 to 8.

10. A bimetallic Ag and Pd loaded WO3 material according to claim 9, characterized in that: Taking the Ag and Pd loaded WO3 nanoparticle material as a reference, the mass percentage of Ag in the Ag and Pd loaded WO3 nanoparticle material is 0.001% to 2.00%, and the mass percentage of Pd in ​​the Ag and Pd loaded WO3 nanoparticle material is 0.001% to 2.00%.

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