A Ni-W 18 O 49 Non-noble metal hydrogen oxidation electrocatalysts and methods of making the same

Abstract

The present application relates to a kind of Ni-W 18 O 49 Non-noble metal hydrogen oxidation electrocatalyst and its preparation method, more particularly to a kind of for efficient hydrogen oxidation reaction (HOR) non-noble metal Ni-W 18 O 49 (Also known as Ni-WO 2.72 ) hetero-composite material electrocatalyst and its preparation method.The Ni-WO 2.72 Hetero-composite material electrocatalyst includes: WO 2.72 Nanosphere and the Ni nanoparticle uniformly loaded on it;The diameter of the WO 2.72 Nanosphere ranges from 500 to 1000 nm, and the loading of the Ni nanoparticle is 0.5-10 wt.%.

Description

TECHNICAL FIELD

[0001] The present application relates to a new type of non-noble metal Ni-W 18 O 49 (also known as Ni-WO 2.72 ) electrocatalyst for high-efficiency hydrogen oxidation reaction (HOR) and its preparation method, belonging to the technical field of inorganic nanomaterials. BACKGROUND

[0002] Hydrogen energy has great significance for solving energy crisis and environmental pollution, and proton exchange membrane fuel cell (PEMFC) is a high-efficiency device that can convert chemical energy in hydrogen into electrical energy. In fuel cells, the anode hydrogen oxidation (HOR) reaction still has only platinum carbon or platinum ruthenium carbon catalysts with high catalytic efficiency. However, the noble metal platinum has many problems such as low reserves, high cost, poor stability and poor CO poisoning resistance, which seriously restricts the large-scale commercialization and application of PEMFC. Tungsten oxide-based catalyst is a good substitute for Pt-based catalyst, which has excellent acid resistance and can form a special hydrogen tungsten bronze (HxWO3) in an acidic environment to promote HOR reaction; moreover, the rich hydroxyl groups on the surface of tungsten oxide can also significantly improve the CO poisoning resistance of the catalyst. However, at present, studies have shown that WO3 has poor electrical conductivity and a small number of active sites, so the HOR catalytic activity and charge transport performance of tungsten oxide-based composite materials without high active sites are poor, which is difficult to meet the demand of practical application. Therefore, it is necessary to improve the catalytic efficiency of HOR by properly regulating tungsten oxide materials and loading high active sites.

[0003] An ideal HOR catalyst should have high activity, low cost, excellent stability and CO poisoning resistance. The poor electrical conductivity of tungsten oxide can be improved by synthesizing non-stoichiometric compound WO 3-x , but the disadvantage of few active sites must be solved by loading high active sites. From the current research progress, the main means is still concentrated on loading platinum on tungsten oxide to obtain high-efficiency HOR catalytic performance, so the problems of cost and poor CO poisoning resistance still exist. At the same time, some non-noble metal catalysts show excellent HOR performance in alkaline electrolyte, but their stability in acidic environment is poor, which makes them difficult to be applied to proton exchange membrane fuel cells. Therefore, it still faces great challenges to synthesize a non-noble metal tungsten oxide-based catalyst as a high-efficiency, durable and CO poisoning-resistant anode HOR electrocatalyst. SUMMARY

[0004] In view of the above problems, the purpose of the present application is to provide a non-noble metal hydrogen oxidation electrocatalyst Ni-W 2.72 and its preparation method.

[0005] In a first aspect, the present application provides a Ni-WO 2.72 The hetero-composite electrocatalyst comprises: WO 2.72 nanospheres and Ni nanoparticles uniformly loaded thereon; the WO 2.72 The diameter of the nanospheres ranges from 500 nm to 1000 nm, and the loading amount of the Ni nanoparticles ranges from 0.5 wt.% to 10 wt.%.

[0006] In the present application, the Ni nanoparticles are loaded on the WO 2.72 nanospheres, and a large number of defects and oxygen vacancies exist on the surface of the WO 2.72 nanospheres, which not only improves the conductivity of the tungsten oxide substrate but also makes it have weak reducibility. This weak reducibility and strong metal-support effect can uniformly anchor the nickel, maximally expose the active sites, and greatly increase the active sites of the tungsten oxide interface. At the same time, the interface electron effect and synergistic catalysis of nickel and tungsten oxide also make the surface electron density of nickel rise, reduce the hydrogen adsorption energy of nickel, accelerate the HOR catalytic process, greatly improve the HOR catalytic efficiency, and obtain the Ni-WO 2.72 hetero-composite electrocatalyst with good HOR catalytic performance, excellent stability and CO poisoning resistance.

[0007] In a second aspect, the present application provides a preparation method of the above-mentioned Ni-WO 2.72 hetero-composite electrocatalyst, comprising the following steps:

[0008] (a) adding a tungsten source into an alcohol solvent, fully stirring until completely dissolved, then transferring the solution containing the tungsten source into an inner liner of a hydrothermal kettle for solvothermal reaction, and then preparing WO 2.72 powder after centrifugation, washing and drying of the product;

[0009] (b) dissolving the WO 2.72 powder obtained in step (a) in an alcohol solvent and adding a nickel source, stirring under a hot water bath condition, adsorbing Ni on the WO 2.72 by using the reducing property of the alcohol solvent, and obtaining a hetero-composite electrocatalyst sample after centrifugation, washing and drying;

[0010] (c) heat-treating the hetero-composite electrocatalyst sample prepared in step (b) in a tube furnace to prepare the Ni-WO 2.72 hetero-composite electrocatalyst.

[0011] Preferably, the tungsten source is at least one of tungsten hexachloride (WCl6), sodium tungstate (Na2WO4·xH2O), potassium tungstate (K2WO4·xH2O) and tungstic acid (H2WO4); and the nickel source is at least one of nickel nitrate hexahydrate (Ni(NO3)2·6H2O), nickel chloride (NiCl2·xH2O) and nickel acetate (Ni(CH3COO)2·xH2O).

[0012] Preferably, in the steps (a) and (b), the alcohol solvent is any one of methanol, ethanol, propanol or polyethylene glycol.

[0013] Preferably, in the step (a), 0.7-1.3 g of the tungsten source is dissolved in 40-80 mL of the alcohol solvent, the solution is kept at 10-20 ℃, and stirred for 20-40 min to obtain a tungsten source solution.

[0014] Preferably, in the step (a), the precursor solution containing the tungsten source is transferred into a 60-100 mL inner liner of an autoclave, and subjected to hydrothermal reaction at 170-190 ℃ for 8-12 h, followed by centrifugation, washing and cold drying to obtain the WO 2.72 powder.

[0015] Preferably, in the step (b), the amount of the WO 2.72 powder is 75-125 mg, the alcohol solvent is 15-25 mL, and the amount of the nickel source is 8-50 mg.

[0016] Preferably, in the step (b), the temperature during stirring under water bath condition is controlled at 60-75 ℃, and the time is 1.5-2.5 h.

[0017] Preferably, in the step (c), the heat treatment is carried out in an inert atmosphere, preferably argon or nitrogen; the temperature of the heat treatment is 100-400 ℃, and the time is 0.75-2 h.

[0018] In a third aspect, the present application further provides a Ni-WO 2.72 hetero-composite electrocatalyst in the catalysis of hydrogen oxidation in an acidic environment.

[0019] The Ni-WO 2.72 hetero-composite electrocatalyst provided in the present application has the advantages of high activity, high stability, low cost, and the like. 2.72The large amount of defects and oxygen vacancies on the surface not only improve the conductivity of the tungsten oxide substrate but also make it have weak reducibility, and the weak reducibility and strong metal-support effect can make the nickel uniformly anchored, maximally expose the active sites, and greatly increase the active sites of the tungsten oxide interface. At the same time, the interface electron effect and synergistic catalysis of nickel and tungsten oxide also make the surface electron density of nickel rise, reduce the hydrogen adsorption energy of nickel, accelerate the HOR catalysis process, and greatly improve the HOR catalysis efficiency. The non-noble metal catalyst has good HOR catalysis performance, excellent stability and CO poisoning resistance, greatly reduces the cost of the catalyst, and has high economic benefit and practical value.

[0020] Advantages

[0021] (1) The present application uses the "alcohol heating method" and the thermal reduction method to load trace amounts of Ni nanoparticles on WO 2.72 , and successfully prepares WO 2.72 materials, and uses the thermal reduction method to prepare transition metal-tungsten oxide heterojunction materials;

[0022] (2) In the Ni-WO 2.72 heterojunction material prepared by the method, the amount of Ni is small (0.5-10 wt.%) and Ni is a non-noble metal with low cost, which has extremely high economic benefit;

[0023] (3) The present application uses an interface electron regulation strategy to anchor Ni on the surface of WO 2.72 to obtain a Ni-WO 2.72 heterojunction material, and the hydrogen overflow effect and synergistic catalysis between Ni and the WO 2.72 substrate greatly improve the HOR catalysis performance, and the prepared heterojunction material has extremely excellent stability and CO poisoning resistance. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 The XRD patterns of the Ni-WO 2.72 heterojunction material prepared in Example 1 of the present application and the WO 2.72 nanospheres prepared in Comparative Example 1;

[0025] Figure 2 The SEM pictures of the Ni-WO 2.72 heterojunction material prepared in the present application, wherein a is the SEM picture of the material in Example 1 (scale 500 nm), b is the TEM picture of the material in Example 1 (scale 200 nm), c is the high-resolution TEM picture of the material in Example 1 (scale 5 nm), and d is the EDS picture of the material in Example 1 (scale 50 nm);

[0026] Figure 3HOR catalytic CV curves and LSV curves of the samples prepared in the present application in 0.5M H2SO4 solution saturated with hydrogen: wherein a, b are respectively CV and LSV curves of the sample of Example 1, the sample of Example 2, the sample of Example 3 and the commercial 20wt.% Pt / C catalyst;

[0027] Figure 4 HOR catalytic LSV curves of the sample of Example 1 and the samples of Comparative Examples 1, 2 and 4 prepared in the present application in 0.5M H2SO4 solution saturated with hydrogen: a is respectively LSV curve of the sample of Example 1, the sample of Comparative Example 1 and the sample of Comparative Example 2, b is respectively LSV curve of the sample of Example 1 and the sample of Comparative Example 4;

[0028] Figure 5 HOR catalytic stability test pictures of the sample of Example 1 and the sample of Comparative Example 3 prepared in the present application in 0.5M H2SO4 solution saturated with hydrogen: wherein a, b are respectively LSV curves of the sample of Example 1 and the sample of Comparative Example 3 before and after 50,000 cycles;

[0029] Figure 6 HOR catalytic CO poisoning resistance test pictures of the sample of Example 1 and the commercial 20wt.% Pt / C catalyst prepared in the present application: wherein a is LSV curve of the sample of Example 1 under pure hydrogen condition, under 1000ppm CO / H2 mixed gas atmosphere and after 10,000 cycles under 1000ppm CO / H2 mixed gas atmosphere; b is LSV curve of the commercial 20wt.% Pt / C catalyst under pure hydrogen condition, under 1000ppm CO / H2 mixed gas atmosphere and after 10,000 cycles under 1000ppm CO / H2 mixed gas atmosphere. DETAILED DESCRIPTION

[0030] The present application will be further described in conjunction with specific embodiments, but the scope of protection of the present application is not limited to the content described.

[0031] In order to overcome the shortcomings of low HOR catalytic efficiency, few active sites and poor conductivity of the existing tungsten oxide material, and to achieve HOR catalytic performance comparable to platinum-based catalysts, the present application provides a method for simultaneously realizing interface electron regulation of tungsten oxide-based material by using "alcohol heat method" and high active site loading, obtaining WO 2.72 hetero-composite material, and provides its application in HOR electrocatalysis.

[0032] In the present application, the Ni-WO 2.72 The morphology is uniform nanospheres, and the Ni is uniformly loaded on the WO 2.72 nanospheres, and the Ni exists in the form of ultra-small nanoparticles. Such ultra-small Ni nanoparticle loading can make it more uniformly distributed on the WO 2.72The nanospheres are loaded with Ni nanoparticles and interact with the nanospheres to promote the catalytic reaction to occur quickly and efficiently.

[0033] WO 2.72 The diameter of the nanospheres ranges from 500 to 1000 nm, and the loading amount of the Ni nanoparticles can be 0.5 to 10 wt.%. If the doping amount of Ni is too high, a large amount of loaded Ni nanoparticles will obviously agglomerate or even fall off during preparation and subsequent catalysis, thereby causing the HOR catalytic performance to obviously attenuate; if the loading amount of Ni is too low, the HOR active sites are too few, so that the HOR catalytic activity is low.

[0034] The Ni-WO 2.72 The hetero-composite electrocatalyst has a HOR catalytic peak current density of 4.3 mA·cm -2 in 0.5 M H2SO4 electrolyte, has good HOR catalytic performance in an acidic environment, and has excellent stability and CO poisoning resistance.

[0035] In some embodiments of the present application, trace Ni nanoparticles prepared by two steps of "alcohol heating method" and thermal reduction method are loaded on WO 2.72 The Ni-WO 2.72 The hetero-composite electrocatalyst can be applied to efficient hydrogen oxidation in an acidic environment. 2.72 The preparation method of the hetero-composite electrocatalyst.

[0036] First, a non-stoichiometric compound WO 2.72 Specifically, 0.7 to 1.3 g of a tungsten source is added to 40 to 80 mL of a methanol, ethanol, propanol or polyethylene glycol solvent, the solution is kept at 10 to 20℃, and stirred for 20 to 40 min to completely dissolve, to obtain a tungsten source solution. Then, the alcohol solution containing the tungsten source is transferred to a 60 to 100 mL inner liner of an autoclave for a solvothermal reaction, the autoclave can be a polytetrafluoroethylene autoclave, and the solvothermal reaction is carried out at 170 to 190℃ for 8 to 12 h. Subsequently, the product is centrifuged, washed and dried to obtain WO 2.72 powder, and the drying method can be cold drying. The tungsten source can be at least one selected from the group consisting of tungsten hexachloride (WCl6), sodium tungstate (Na2WO4·xH2O), potassium tungstate (K2WO4·xH2O) and tungstic acid (H2WO4).

[0037] Then, the obtained WO 2.72The powder 75-125 mg is dissolved in 15-25 mL of methanol, ethanol, propanol or polyethylene glycol alcohol solvent and 8-50 mg of nickel source is added, and stirred in a hot water bath at 60-75 °C for 1.5-2.5 h, and the Ni is adsorbed on the WO 2.72 by the reducing property of the alcohol solvent, and the heterogeneous composite electrocatalyst sample is obtained after centrifugation, washing and drying. The nickel source can be at least one of nickel nitrate hexahydrate (Ni(NO3)2·6H2O), nickel chloride (NiCl2·xH2O) and nickel acetate (Ni(CH3COO)2·xH2O), and the Ni loading is controlled to be 0.5-10 wt.%.

[0038] Finally, the above-mentioned heterogeneous composite electrocatalyst sample is heat-treated in a tube furnace, the heat treatment atmosphere is an inert gas such as argon or nitrogen, and the heat treatment is carried out at 100-400 °C for 0.75-2 h, and the Ni-WO 2.72 heterogeneous composite electrocatalyst is prepared. The Ni clusters are anchored on the surface of the WO 2.72 nanospheres through the heat treatment process, and if the heat treatment temperature is too low or no heat treatment is carried out, the Ni clusters will not be combined tightly with the WO 2.72 nanospheres, and the stability will be reduced; if the heat treatment time is too long, the material will be aggregated, and the HOR catalytic performance will be reduced; and if the heat treatment temperature is too high, the structure of the catalyst will be damaged, and the HOR performance will be reduced.

[0039] As a preparation scheme of the Ni-WO 2.72 heterogeneous composite electrocatalyst, the following steps are included:

[0040] (1) 0.7-1.3 g of tungsten hexachloride is dissolved in 40-80 mL of anhydrous ethanol, the solution is kept at 10-20 °C, and magnetic stirring is carried out for 20-40 min to obtain a tungsten source solution;

[0041] (2) The tungsten source solution obtained in step (1) is transferred into an inner liner of a 80 mL Teflon autoclave, and is placed in an oven for hydrothermal reaction at 170-190 °C for 8-12 h;

[0042] (3) The mixed solution prepared in step (2) is centrifuged, washed with anhydrous ethanol and deionized water for 5-8 times, and freeze-dried to obtain a WO 2.72 powder;

[0043] (4) 75-125 mg of the above-mentioned WO 2.72 powder is dissolved in 15-25 mL of anhydrous ethanol, 8-50 mg of nickel nitrate hexahydrate crystal is added, and the Ni loading is controlled to be 0.5-10 wt.%;

[0044] (5) the mixed solution prepared in step (4) is placed in a water bath at 60-75°C and stirred for 1.5-2.5 h, then washed with anhydrous ethanol and deionized water for 4-6 times after centrifugation, and dried in a vacuum drying oven to obtain a catalyst sample;

[0045] (6) the sample prepared in step (5) is placed in a tube furnace under an argon atmosphere and heat treated at 100-400°C for 0.75-2 h to obtain the Ni-WO 2.72 hetero-composite material.

[0046] The Ni-WO 2.72 hetero-composite material prepared according to the above process flow is nanospherical, with a diameter of about 500-1000 nm, and the Ni is uniformly loaded on the WO 2.72 nanospheres, and has good HOR electrocatalytic performance in an acidic electrolyte, excellent stability and excellent CO poisoning resistance.

[0047] The following examples are further illustrated to explain the present application. It should also be understood that the following examples are only used to further illustrate the present application, and cannot be understood as limiting the protection scope of the present application. Some non-essential improvements and adjustments made by those skilled in the art according to the above content of the present application are within the protection scope of the present application. The specific process parameters in the following examples are only one example in the appropriate range, i.e. those skilled in the art can make appropriate selection within the range according to the description herein, and are not limited to the specific values in the following examples.

[0048] Example 1

[0049] According to the above technical solution and process flow of the present application, 1 g of tungsten hexachloride is dissolved in 60 mL of anhydrous ethanol and stirred for 30 min, the solution is transferred into an 80 mL Teflon hydrothermal kettle liner, and placed in an oven for hydrothermal reaction at 180°C for 10 h. After cooling, the mixed solution is centrifuged, and the centrifuged product is washed with anhydrous ethanol and deionized water for 6 times, then frozen and placed in a freeze dryer for freeze-drying to obtain a non-stoichiometric WO 2.72 powder. 100 mg of the WO 2.72 powder is dissolved in 20 mL of anhydrous ethanol, and 24 mg of nickel nitrate hexahydrate crystals are added to obtain a mixed solution, which is then placed in a 70°C water bath and stirred for 2 h. After centrifugation, the product is washed with anhydrous ethanol and deionized water for 6 times, and dried in a vacuum drying oven to obtain a powder sample. The powder sample is placed in a tube furnace under an argon atmosphere and heat treated at 300°C for 1 h to obtain a Ni-WO 2.72 hetero-composite material, and the obtained material is named Ni-WO 2.72 -24.

[0050] The prepared material is mainly WO 2.72 material, such as Figure 1As shown in the XRD pattern, the main morphology is nanospheres with a diameter of about 400 to 600 nm, as shown in SEM ( Figure 2 a) and TEM( Figure 2 As shown in the picture in b), high-resolution TEM ( Figure 2 The lattice fringe with d = 0.38 nm in c) corresponds to WO 2.72 (010) crystal plane, EDS ( Figure 2 d) shows that Ni element is present in WO 2.72 The uniform loading on the substrate, the theoretical loading of Ni is 4.77 wt.%, and the peak current density can reach 4.3 mA cm in 0.5 M H2SO4 solution saturated with hydrogen. -2 (like Figure 3 The CV curve in a and Figure 3 b). Moreover, the peak current density of HOR catalysis in acidic environment did not decrease significantly after 50,000 cycles (as shown in the LSV curve). Figure 5 In a 1000ppm CO / H2 mixed atmosphere, the HOR catalytic peak current density showed no significant attenuation compared to that in a pure hydrogen environment, and there was no significant performance degradation after 10,000 cycles in the mixed atmosphere (as shown in Figure 2). Figure 6 a). The above description of the Ni-WO 2.72 The heterogeneous composite material not only exhibits good HOR catalytic performance but also possesses excellent resistance to CO poisoning and stability.

[0051] Example 2

[0052] According to the process flow in Example 1, the amount of nickel nitrate hexahydrate crystals added was 8 mg, and other operating conditions were the same as in Example 1. The obtained material was named Ni-WO 2.72 -8, with a theoretical Ni loading of 1.59 wt.%, and a peak current density of 3.7 mA cm in a hydrogen-saturated 0.5 M H2SO4 solution. -2 (like Figure 3 The CV curve in a and Figure 3 b LSV curve).

[0053] Example 3

[0054] According to the process flow in Example 1, the amount of nickel nitrate hexahydrate crystals added was 48 mg, and other operating conditions were the same as in Example 1. The obtained material was named Ni-WO 2.72 -48, with a theoretical Ni loading of 9.54 wt.%, and a peak current density of 3.7 mA cm in a hydrogen-saturated 0.5 M H2SO4 solution. -2 (like Figure 3 The CV curve in a and Figure 3(shown as LSV curve in b).

[0055] Comparative Example 1

[0056] According to the process flow (same as Example 1), no nickel source was added, and other operations were the same as Example 1. The prepared material was WO 2.72 Nanosphere material, its XRD spectrum is as follows Figure 1 As shown in Figure 2, the peak current density in a hydrogen-saturated 0.5 M H2SO4 solution is only 2.5 mA cm -2 (like Figure 4 a), compared with the Ni-WO prepared in Example 1 2.72 -24 heterogeneous composite material HOR catalytic performance is much worse.

[0057] Comparative Example 2

[0058] According to the process flow in Example 1, the amount of nickel nitrate hexahydrate crystals added was 72 mg, and other operating conditions were the same as in Example 1. The obtained material was named Ni-WO 2.72 -72, whose theoretical Ni loading is 14.31 wt.%, and its peak current density in hydrogen-saturated 0.5 M H2SO4 solution is only 3.1 mA cm -2 (like Figure 4 The results show that the high loading of Ni will affect its HOR catalytic performance.

[0059] Comparative Example 3

[0060] According to the process flow (same as Example 1), no heat treatment process is performed, and other operations are the same as Example 1. The prepared material is Ni-WO 2.72 -A nanosphere material, with a peak current density of 4.2 mA cm in a hydrogen-saturated 0.5 M H2SO4 solution -2 , but its peak current density decreased by about 5% after 50,000 cycles in an acidic environment (e.g. Figure 5 b), compared with the Ni-WO prepared in Example 1 2.72 The poor stability of the -24 heterogeneous composite material indicates the necessity of the heat treatment step. At the same time, since the material was dried in a vacuum oven at 80°C, it also shows that lower heat treatment temperatures will also affect its stability.

[0061] Comparative Example 4

[0062] According to the process flow (same as in Example 1), the heat treatment temperature was adjusted to 600°C, and other operations were the same as in Example 1. The prepared material was Ni-WO 2.72-24-600 °C nanospheres material with a peak current density of only 3.2 mA-cm -2 (As Figure 4 b), which was prepared in Example 1, and the Ni-WO 2.72 -24Heterogeneous composite material with poor performance, which indicates that if the heat treatment temperature is too high, the performance will be affected.

Claims

1. A Ni-WO 2.72 A method for preparing a heterogeneous composite electrocatalyst, characterized in that: The Ni-WO 2.72 Heterogeneous composite electrocatalysts include: WO 2.72 Nanospheres and Ni nanoparticles uniformly loaded thereon; the WO 2.72 The diameter of the nanospheres ranges from 500 to 1000 nm, and the loading amount of the Ni nanoparticles is 0.5 to 10 wt.%; The preparation method comprises the following steps: (a) The tungsten source is added to an alcohol solvent and stirred thoroughly until completely dissolved. The solution containing the tungsten source is then transferred to the lining of a hydrothermal reactor for solvothermal reaction. The product is then centrifuged, washed, and dried to obtain WO. 2.72 powder; (b) The WO obtained in step (a) 2.72 The powder is dissolved in an alcohol solvent and a nickel source is added. The mixture is stirred in a hot water bath and the reducing property of the alcohol solvent is used to adsorb Ni onto WO. 2.72 After centrifugation, washing and drying, the heterogeneous composite electrocatalyst sample was obtained; In step (b), the WO 2.72 The amount of powder used is 75 to 125 mg, the amount of the alcohol solvent used is 15 to 25 mL, and the amount of the nickel source is 8 to 50 mg; the stirring temperature in a water bath is controlled at 60 to 75° C., and the stirring time is 1.5 to 2.5 hours; (c) The heterogeneous composite electrocatalyst sample prepared in step (b) is heat-treated in a tube furnace to obtain the Ni-WO 2.72 Heterogeneous composite electrocatalysts; The heat treatment temperature is 100-400° C., and the time is 0.75-2 h.

2. The preparation method according to claim 1, characterized in that The tungsten source is at least one of tungsten hexachloride, sodium tungstate, potassium tungstate and tungstic acid; the nickel source is at least one of nickel nitrate hexahydrate, nickel chloride and nickel acetate.

3. The preparation method according to claim 1, characterized in that In the steps (a) and (b), the alcohol solvent is any one of methanol, ethanol, propanol or polyethylene glycol.

4. The preparation method according to claim 1, wherein In the step (a), 0.7-1.3 g of tungsten source is dissolved in 40-80 mL of alcohol solvent, the solution is kept at 10-20° C., and stirred for 20-40 minutes to obtain the solution containing the tungsten source.

5. The preparation method according to claim 1, wherein In the step (a), the solution containing the tungsten source is transferred to the inner lining of a 60-100 mL hydrothermal reactor, and the hydrothermal reaction is carried out at 170-190° C. for 8-12 h, followed by centrifugation, washing, and freeze-drying to obtain the WO 2.72 powder.

6. The preparation method according to claim 1, characterized in that In the step (c), the heat treatment is performed in an inert atmosphere, which is argon or nitrogen.

7. Ni-WO obtained by the preparation method according to claim 1 2.72 Application of heterogeneous composite electrocatalysts in hydrogen oxidation catalysis in acidic environment.

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