Pd-foamed nickel hydrogen evolution catalyst as well as preparation method and application thereof

Abstract

The invention provides a Pd-foamed nickel hydrogen evolution catalyst and a preparation method and application thereof.The preparation method of the Pd-foamed nickel hydrogen evolution catalyst comprises the following steps that a mixed solution containing sodium chloride and palladium chloride is used for conducting electric etching-deposition treatment on foamed nickel, and the Pd-foamed nickel hydrogen evolution catalyst is obtained; wherein the electric etching-deposition treatment is carried out by using a cyclic voltammetry method. According to the preparation method of the Pd-foamed nickel hydrogen evolution catalyst, the catalyst with low overpotential and high stability can be prepared, and the method has the advantages of being short in step, easy to operate, high in practical operability and the like.

Description

Technical Field

[0001] The invention belongs to the technical field of catalysts, and in particular relates to a Pd-nickel foam hydrogen evolution catalyst and a preparation method and application thereof. Background Art

[0002] With the growing global demand for clean energy, hydrogen, a clean energy source with high energy density and zero carbon dioxide emissions, has garnered widespread attention. Hydrogen can be produced through a variety of pathways, with water electrolysis and photolysis being two effective methods for producing pure hydrogen. Water electrolysis, in particular, has become a research hotspot in recent years due to its simple process and high-purity hydrogen production.

[0003] The key to hydrogen production from water electrolysis lies in the performance of the electrocatalyst. However, existing electrocatalysts for hydrogen production from water electrolysis cannot simultaneously achieve both low overpotential and long life. Therefore, developing a hydrogen evolution catalyst that can achieve both low overpotential and long life is of great significance for promoting the development of hydrogen energy technology. Summary of the Invention

[0004] The main purpose of the present invention is to provide a method for preparing a Pd-nickel foam hydrogen evolution catalyst. The Pd-nickel foam hydrogen evolution catalyst prepared by the preparation method can simultaneously achieve the characteristics of low overpotential and high stability.

[0005] The present invention also provides a Pd-nickel foam hydrogen evolution catalyst, which is prepared using the above preparation method. Therefore, the Pd-nickel foam hydrogen evolution catalyst can simultaneously achieve the characteristics of low overpotential and high stability.

[0006] The present invention also provides a method for electrolyzing water, which has the advantages of high hydrogen evolution efficiency, low cost and wide application.

[0007] In a first aspect, the present invention provides a method for preparing a Pd-nickel foam hydrogen evolution catalyst, comprising the following steps:

[0008] Performing an electro-etching-deposition process on the nickel foam using a mixed solution comprising sodium chloride and palladium chloride to obtain the Pd-nickel foam hydrogen evolution catalyst;

[0009] Wherein, the electro-etching-deposition process is performed using cyclic voltammetry.

[0010] In the preparation method of the Pd-nickel foam hydrogen evolution catalyst as described above, the mass percentage of Pd in ​​the Pd-nickel foam hydrogen evolution catalyst is 0.1% to 0.5%.

[0011] In the preparation method of the Pd-nickel foam hydrogen evolution catalyst as described above, the number of pores per inch of the nickel foam is 95 to 110.

[0012] The method for preparing the Pd-nickel foam hydrogen evolution catalyst as described above further comprises, before the electro-etching-deposition treatment, washing the nickel foam with hydrochloric acid solution, acetone and deionized water in sequence.

[0013] In the method for preparing the Pd-nickel foam hydrogen evolution catalyst as described above, the temperature of the electro-etching-deposition treatment is 30° C. to 50° C., and the time is 8 min to 10 min.

[0014] In the preparation method of the Pd-nickel foam hydrogen evolution catalyst as described above, the molar concentration of palladium chloride in the mixed solution is 0.8 mM to 1.2 mM.

[0015] In the preparation method of the Pd-nickel foam hydrogen evolution catalyst as described above, the molar concentration of sodium chloride in the mixed solution is 5.8M to 6.2M.

[0016] In a second aspect, the present invention provides a Pd-nickel foam hydrogen evolution catalyst, which is prepared according to the preparation method of the Pd-nickel foam hydrogen evolution catalyst as described above.

[0017] In a third aspect, the present invention provides a method for electrolyzing water, wherein the Pd-nickel foam hydrogen evolution catalyst as described above is used to electrolyze water.

[0018] The electrolysis method of water as described above, wherein the electrolysis treatment conditions include: a current density of 10 mA / cm 2 ~1000mA / cm 2 ;

[0019] And / or, the electrolyte for the electrolytic treatment is a potassium hydroxide solution, and the molar concentration of the potassium hydroxide solution is 1M to 6M.

[0020] The present invention provides a method for preparing a Pd-nickel foam hydrogen evolution catalyst, capable of producing a catalyst with low overpotential and high stability. The method has the advantages of short steps, simple operation, and strong practicality. During the preparation process, the nickel foam is etched to increase the number of active sites on the catalyst. Simultaneously, a Pd-Ni alloy is loaded on the surface of the nickel foam to optimize the hydrogen adsorption free energy, facilitating the conversion of adsorbed hydrogen into hydrogen gas, thereby imparting a low overpotential to the catalyst. Furthermore, due to the in-situ synthesis method and the high stability of the resulting Pd-Ni alloy, the catalyst exhibits high stability, ensuring a long service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention or related technologies, the following briefly introduces the drawings required for use in the embodiments of the present invention or related technologies. Obviously, the drawings described below are only some embodiments of the present invention. Those skilled in the art can also derive other drawings based on these drawings without inventive effort.

[0022] Figure 1 This is a SEM image of the nickel foam used in Example 1 of the present invention;

[0023] Figure 2 This is a SEM image of the Pd-nickel foam hydrogen evolution catalyst prepared in Example 1 of the present invention;

[0024] Figure 3 This is an SEM image of the Pd-nickel foam hydrogen evolution catalyst prepared in Example 2 of the present invention;

[0025] Figure 4 This is an SEM image of the Pd-nickel foam hydrogen evolution catalyst prepared in Example 3 of the present invention;

[0026] Figure 5 This is an SEM image of the Pd-nickel foam hydrogen evolution catalyst prepared in Example 4 of the present invention;

[0027] Figure 6 This is an SEM image of the Pd-nickel foam hydrogen evolution catalyst prepared in Example 5 of the present invention;

[0028] Figure 7 This is an EDS image (Pd element) of the Pd-nickel foam hydrogen evolution catalyst prepared in Example 4 of the present invention;

[0029] Figure 8 This is an EDS image (Ni element) of the Pd-nickel foam hydrogen evolution catalyst prepared in Example 4 of the present invention;

[0030] Figure 9 This is the LSV curve of the Pd-nickel foam hydrogen evolution catalyst prepared in Examples 1 to 12 of the present invention. DETAILED DESCRIPTION

[0031] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with 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 making creative efforts shall fall within the scope of protection of the present invention.

[0032] Based on this, in a first aspect, the present invention provides a method for preparing a Pd-nickel foam hydrogen evolution catalyst, comprising the following steps:

[0033] A mixed solution comprising sodium chloride and palladium chloride is used to perform an electro-etching-deposition treatment on nickel foam to obtain a Pd-nickel foam hydrogen evolution catalyst; wherein the electro-etching-deposition treatment is performed using cyclic voltammetry.

[0034] It can be understood that foam nickel is a porous metal nickel with a sponge structure and has a high specific surface area.

[0035] The present invention does not limit the shape and size of the nickel foam, and can be selected according to actual needs.

[0036] The present invention uses a mixed solution including sodium chloride and palladium chloride to perform an electro-etching-deposition treatment on nickel foam, wherein the chloride ions can etch the nickel foam, and the etching treatment can be performed on the entire nickel foam or on a portion of the nickel foam. The palladium element is deposited on the surface of the nickel foam. The electro-etching-deposition treatment of the present invention can be performed using cyclic voltammetry, which can achieve simultaneous etching of the nickel foam and deposition of the metal element. It is understood that after the nickel foam is etched, the nickel element will dissolve and redeposit on the surface of the nickel foam, so that the etched nickel foam contains the nickel element, thereby forming a Pd-Ni alloy on the surface of the nickel foam.

[0037] The inventors discovered that palladium metal has an excellent hydrogen adsorption free energy, enabling efficient hydrogen evolution catalysis. However, its high hydrogen adsorption free energy makes it difficult for the catalytically evolved hydrogen to escape, resulting in poor hydrogen evolution. However, when nickel is combined with palladium metal, this overflow barrier can be effectively overcome, allowing large amounts of hydrogen to escape efficiently for collection.

[0038] According to the above method provided by the present invention, a Pd-nickel foam hydrogen evolution catalyst is prepared, which has a low overpotential and high stability. The reason for this is that when the chloride ions in the mixed solution achieve a suitable etching effect on the nickel foam, on the one hand, the active surface area of ​​the nickel foam is effectively increased, which contributes to the growth of a large number of active sites, thereby reducing the overpotential of the catalyst and improving the hydrogen evolution performance of the catalyst; on the other hand, the palladium and nickel interact with each other, optimizing the hydrogen adsorption free energy to approach 0, making it easier for the adsorbed hydrogen to adsorb on the surface of the Pd-Ni alloy to generate hydrogen, thereby giving the catalyst a low overpotential.

[0039] In addition, the catalyst of the present invention adopts an in-situ synthesis method, so that the Pd-Ni alloy and the nickel foam have strong adhesion, and the nickel foam and the Pd-Ni alloy have high stability, so that the catalyst has high stability.

[0040] The catalyst preparation method of the present invention can prepare the target catalyst through a simple one-step process. The preparation method is short in steps, simple in operation, and highly practical, and provides a basis for the expanded production of Pd-nickel foam hydrogen evolution catalysts.

[0041] The mass percentage of palladium in the Pd-nickel foam hydrogen evolution catalyst of the present invention can be obtained through ICP-OES testing.

[0042] In some embodiments of the present invention, the mass percentage of Pd in ​​the Pd-nickel foam hydrogen evolution catalyst is 0.1% to 0.5%, for example, it can be 0.1%, 0.2%, 0.3%, 0.35%, 0.4%, 0.5% or any two thereof.

[0043] The present invention's Pd content in the Pd-nickel foam hydrogen evolution catalyst is within the aforementioned range, effectively forming a Pd-Ni alloy and optimizing the hydrogen adsorption free energy to approach zero, making it easier for adsorbed hydrogen to adsorb onto the Pd-Ni alloy surface to generate hydrogen gas, thereby imparting a low overpotential to the catalyst. Furthermore, the Pd content is no greater than 0.5%, and nickel foam is used as the substrate. Therefore, the catalyst offers the advantages of low cost and a simple manufacturing process.

[0044] In some embodiments of the present invention, the number of pores per inch (PPI) of the nickel foam is 95-110, for example, it can be 95, 96, 97, 98, 99, 100, 105, 110 or a range consisting of any two thereof.

[0045] When the PPI of nickel foam is within the above range, it is helpful to prepare the above target catalyst, and more Pd-Ni alloy can be grown on the surface of nickel foam, so that the catalyst has more active sites, thereby making the catalyst have a low overpotential.

[0046] In some embodiments of the present invention, the electro-etching-deposition process further includes: washing the nickel foam with hydrochloric acid solution, acetone and deionized water in sequence.

[0047] Specifically, before the electro-etching-deposition treatment, the nickel foam is first washed with a hydrochloric acid solution, then washed with acetone, and finally washed with deionized water and dried to obtain a clean nickel foam. Cleaning the nickel foam can reduce the introduction of impurities during the catalyst preparation process and prevent impurities from reacting with the mixed solution of palladium chloride and sodium chloride, thereby ensuring the purity of the target catalyst to a greater extent.

[0048] The present invention does not impose any particular restrictions on the cleaning method of the nickel foam or the concentration of the hydrochloric acid solution, as long as the nickel foam can be cleaned. For example, the nickel foam can be ultrasonically cleaned in hydrochloric acid at an ultrasonic frequency of 30 to 50 Hz for 20 to 40 minutes, then ultrasonically cleaned in acetone for 20 to 40 minutes, and finally ultrasonically cleaned in deionized water for 20 to 40 minutes to obtain a clean nickel foam.

[0049] In some embodiments of the present invention, the temperature of the electro-etching-deposition treatment is 30°C to 50°C, for example, it can be 30°C, 35°C, 40°C, 45°C, 50°C or a range consisting of any two thereof; the time is 8min to 10min, for example, it can be 8min, 8.5min, 9min, 9.5min, 10min or a range consisting of any two thereof.

[0050] When the temperature and time of the electro-etching-deposition treatment are controlled within the above ranges, the nickel foam is conducive to achieving an appropriate degree of etching. A large number of etching sites exist on the surface of the nickel foam, and the hollow nickel foam cracks. The effective active surface area of ​​the nickel foam increases, which is conducive to the growth of a large number of active sites, thereby reducing the hydrogen evolution overpotential of the catalyst. At the same time, the nickel foam can maintain a complete pore structure and good mechanical strength, thereby avoiding structural collapse of the catalyst and ensuring the excellent catalytic hydrogen evolution performance of the catalyst.

[0051] In some embodiments of the present invention, the molar concentration of palladium chloride in the mixed solution is 0.8 mM to 1.2 mM, for example, 0.8 mM, 0.9 mM, 1.0 mM, 1.1 mM, 1.2 mM or any two thereof.

[0052] Palladium chloride and sodium chloride mixed solution is by being dispersed in deionized water by palladium chloride (PdCl2) and sodium chloride (NaCl), and then mixing and preparing into aqueous solution. The present invention does not limit the mixing mode in the preparation process of palladium chloride and sodium chloride mixed solution, for example, ultrasonic treatment can be selected, and ultrasonic frequency is 60Hz~90Hz, and ultrasonic time is 150min~200min; For example, magnetic stirring process can be selected, and stirring speed (S.S.) is 100rpm, and stirring time is 12h. When the molar concentration of palladium chloride is within the above range, so that enough palladium ions are included in the mixed solution, so that enough palladium can be deposited on the surface of nickel foam, improve the efficiency of electroetching-deposition process, and the use of low concentration of palladium chloride can reduce the preparation cost of hydrogen evolution catalyst, so that low-cost hydrogen evolution catalyst can be prepared.

[0053] In some embodiments of the present invention, the molar concentration of sodium chloride in the mixed solution is 5.8M to 6.2M, for example, 5.8M, 6.0M, 6.04M, 6.08M, 6.1M, 6.12M, 6.16M, 6.2M or a range consisting of any two thereof.

[0054] When the molar concentration of sodium chloride in the mixed solution is within the above range, the chloride ion content is sufficient, and the nickel foam can be fully electro-etched, so that the active surface area of ​​the nickel foam is effectively increased, which is conducive to the growth of a large number of active sites, thereby reducing the overpotential of the catalyst and improving the hydrogen evolution performance of the catalyst.

[0055] In a second aspect, the present invention provides a Pd-nickel foam hydrogen evolution catalyst, which is prepared according to the preparation method of the Pd-nickel foam hydrogen evolution catalyst as described above. Therefore, the Pd-nickel foam hydrogen evolution catalyst has the advantages of low overpotential and high stability.

[0056] In a third aspect, the present invention provides a method for electrolyzing water, wherein the Pd-nickel foam hydrogen evolution catalyst as described above is used to electrolyze water.

[0057] Since the water electrolysis method adopts a Pd-nickel foam hydrogen evolution catalyst, the water electrolysis method has the advantages of high hydrogen evolution efficiency, low cost and wide application.

[0058] In some embodiments of the present invention, the electrolytic treatment conditions include: a current density of 10 mA / cm 2 ~1000mA / cm 2 , for example, it can be 10mA / cm 2 , 50mA / cm 2 , 100mA / cm 2 , 500mA / cm 2 , 1000mA / cm 2 or a range consisting of any two of them.

[0059] In some embodiments, the electrolyte for electrolysis treatment is a potassium hydroxide solution, and the molar concentration of the potassium hydroxide solution is 1M to 6M, for example, 1M, 2M, 3M, 4M, 5M, 6M or any two thereof.

[0060] When the current density and the concentration of the electrolytic solution used in the water electrolysis process are respectively within the above ranges, the Pd-nickel foam hydrogen evolution catalyst can carry out the electrocatalytic hydrogen evolution reaction and can work for a long time, indicating that the Pd-nickel foam hydrogen evolution catalyst has a wide range of applications and can adapt to different conditions to perform long-term and efficient catalytic effects.

[0061] The technical solution of the present invention is further described below with reference to specific embodiments.

[0062] Example 1

[0063] The preparation method of the Pd-nickel foam hydrogen evolution catalyst of the present embodiment comprises the following steps:

[0064] 1) A nickel foam with a PPI of 95 and a size of 1 cm×1.5 cm was ultrasonically washed in a 3M hydrochloric acid solution for 30 min, then ultrasonically washed in acetone for 30 min, and finally ultrasonically washed in deionized water for 30 min at an ultrasonic frequency of 30 Hz.

[0065] 2) The washed nickel foam was used as a working electrode and immersed in a mixed solution of sodium chloride and palladium chloride. Electrodeposition was performed using cyclic voltammetry. The nickel foam was then removed and dried under vacuum at room temperature for 12 hours to obtain a Pd-nickel foam hydrogen evolution catalyst. The molar concentration of palladium chloride in the mixed solution was 1 mM, the molar concentration of sodium chloride in the mixed solution was 6.12 M, and the electrodeposition temperature was 40°C for 4 minutes.

[0066] Example 2

[0067] The preparation methods of the Pd-nickel foam hydrogen evolution catalysts in Example 2 and Example 1 are basically the same, except that the time for the electro-etching-deposition treatment is 6 minutes.

[0068] Example 3

[0069] The preparation methods of the Pd-nickel foam hydrogen evolution catalysts in Example 3 and Example 1 are basically the same, except that the time for the electro-etching-deposition treatment is 8 minutes.

[0070] Example 4

[0071] The preparation methods of the Pd-nickel foam hydrogen evolution catalysts in Example 4 and Example 1 are basically the same, except that the time for the electro-etching-deposition treatment is 10 minutes.

[0072] Example 5

[0073] The preparation methods of the Pd-nickel foam hydrogen evolution catalysts in Example 5 and Example 1 are basically the same, except that the time for the electro-etching-deposition treatment is 12 minutes.

[0074] Example 6

[0075] The preparation methods of the Pd-nickel foam hydrogen evolution catalysts of Example 6 and Example 4 are basically the same, except that the PPI of the nickel foam is 75.

[0076] Example 7

[0077] The preparation methods of the Pd-nickel foam hydrogen evolution catalysts of Example 7 and Example 4 are basically the same, except that the PPI of the nickel foam is 110.

[0078] Example 8

[0079] The preparation methods of the Pd-nickel foam hydrogen evolution catalysts in Example 8 and Example 4 are basically the same, except that the PPI of the nickel foam is 120.

[0080] Example 9

[0081] The preparation methods of the Pd-nickel foam hydrogen evolution catalysts in Example 9 and Example 4 are basically the same, except that the molar concentration of palladium chloride in the mixed solution is 0.5 mM.

[0082] Example 10

[0083] The preparation methods of the Pd-nickel foam hydrogen evolution catalysts in Example 10 and Example 4 are basically the same, except that the molar concentration of palladium chloride in the mixed solution is 0.8 mM.

[0084] Example 11

[0085] The preparation methods of the Pd-nickel foam hydrogen evolution catalysts in Example 11 and Example 4 are basically the same, except that the molar concentration of palladium chloride in the mixed solution is 1.2 mM.

[0086] Example 12

[0087] The preparation methods of the Pd-nickel foam hydrogen evolution catalysts in Example 12 and Example 4 are basically the same, except that the molar concentration of palladium chloride in the mixed solution is 1.5 mM.

[0088] Example 13

[0089] The preparation methods of the Pd-nickel foam hydrogen evolution catalysts of Example 13 and Example 4 are basically the same, except that the temperature of the electro-etching-deposition treatment is 20°C.

[0090] Example 14

[0091] The preparation method of the Pd-nickel foam hydrogen evolution catalyst in Example 14 is basically the same as that in Example 4, except that the temperature of the electro-etching-deposition treatment is 30°C.

[0092] Example 15

[0093] The preparation methods of the Pd-nickel foam hydrogen evolution catalysts in Example 15 and Example 4 are basically the same, except that the temperature of the electro-etching-deposition treatment is 50°C.

[0094] Example 16

[0095] The preparation methods of the Pd-nickel foam hydrogen evolution catalysts of Example 16 and Example 4 are basically the same, except that the temperature of the electro-etching-deposition treatment is 60°C.

[0096] Example 17

[0097] The preparation methods of the Pd-nickel foam hydrogen evolution catalysts in Example 17 and Example 4 are basically the same, except that the molar concentration of sodium chloride in the mixed solution is 5.8M.

[0098] Example 18

[0099] The preparation methods of the Pd-nickel foam hydrogen evolution catalysts in Example 18 and Example 4 are basically the same, except that the molar concentration of sodium chloride in the mixed solution is 6.2M.

[0100] Comparative Example 1

[0101] The preparation method of the Pd-nickel foam hydrogen evolution catalyst of Comparative Example 1 comprises the following steps:

[0102] 1) A nickel foam with a PPI of 95 and a size of 1 cm×1.5 cm was ultrasonically washed in a 3M hydrochloric acid solution for 30 min, then ultrasonically washed in acetone for 30 min, and finally ultrasonically washed in deionized water for 30 min at an ultrasonic frequency of 30 Hz.

[0103] 2) The washed nickel foam was used as a working electrode and immersed in a mixed solution of sodium chloride and palladium chloride. A deposition process was performed using a constant current method. The nickel foam was then removed and dried under vacuum at room temperature for 12 hours to obtain a Pd-nickel foam hydrogen evolution catalyst. The molar concentration of palladium chloride in the mixed solution was 1 mM, the molar concentration of sodium chloride in the mixed solution was 6.04 M, and the deposition process was performed at a current of 6 mA for 10 minutes.

[0104] Test example:

[0105] 1. The Pd-nickel foam hydrogen evolution catalysts of the examples and comparative examples were subjected to ICP-OES testing using an Agilent ICP-OES 725ES. The mass content of palladium in the hydrogen evolution catalysts was obtained by analysis and calculation. The relevant data are shown in Table 1.

[0106] 2. The Pd-nickel foam hydrogen evolution catalysts of the embodiment and the comparative example were subjected to SEM testing and energy dispersive spectrometry (EDS) testing. The SEM image of the nickel foam used in Example 1 is shown in FIG. Figure 1 ,Depend on Figure 1 It can be seen that the surface of the nickel foam is smooth and the nickel foam skeleton is not damaged. The SEM images of the Pd-nickel foam hydrogen evolution catalysts prepared in Examples 1 to 5 are shown in FIG. Figures 2 to 6 ,Depend on Figures 2 to 6It can be seen that as the etching time of nickel foam in the mixed solution of sodium chloride and palladium chloride increases, the surface roughness of nickel foam increases and the active surface area of ​​nickel foam increases, until the structure of nickel foam in Example 5 breaks and the structural stability of nickel foam deteriorates. The EDS diagram of Pd-nickel foam hydrogen evolution catalyst of Example 4 is shown in FIG. Figure 7 and Figure 8 ,Depend on Figure 7 and Figure 8 It can be seen that Ni and Pd elements are evenly distributed on the catalyst surface.

[0107] 3. In a three-electrode system, the Pd-nickel foam hydrogen evolution catalysts of the embodiment and the comparative example were used as the working electrode, a graphite sheet was used as the counter electrode, and a Hg / HgO electrode was used as the reference electrode. Linear sweep voltammetry was performed in a 1 M KOH aqueous solution filled with nitrogen at a sweep rate of 5 mV / s. The overpotential of the catalyst was measured at a current density of 1000 mA / cm 2 The specific data of overpotential under 200 nm are shown in Table 1.

[0108] The linear sweep voltammetry (LSV) curves of the Pd-nickel foam hydrogen evolution catalysts of Examples 1 to 12 are shown in FIG. Figure 9 As shown by Figure 9 It can be seen that the Pd-nickel foam hydrogen evolution catalyst of Example 4 has the best hydrogen evolution catalytic performance.

[0109] 4. In a three-electrode system, the Pd-nickel foam hydrogen evolution catalyst of Example 4 was used as the working electrode, a graphite sheet was used as the counter electrode, and a Hg / HgO electrode was used as the reference electrode. The results were recorded at 1000 mA / cm in a 1 M KOH aqueous solution filled with nitrogen and in an electrolyte containing 6 M KOH under industrial conditions. 2 The stability of the catalyst was measured by constant current test at 25 °C with a current density of 1.5 wt %. The specific data are shown in Table 2.

[0110] Table 1

[0111]

[0112]

[0113] Table 2

[0114]

[0115] Compared with the comparative example, the preparation method of the Pd-nickel foam hydrogen evolution catalyst provided by the present invention can prepare a catalyst with low overpotential and high stability. The method has the advantages of short steps, simple operation, and strong practicality.

[0116] According to the comparison of Examples 1 to 5, it can be seen that when the etching treatment time is 8 min to 10 min, it helps to make the catalyst have a lower overpotential; according to the comparison of Examples 4, 6, 7, and 8, when the PPI of the nickel foam is 95 to 110, the prepared catalyst has a lower overpotential; according to the comparison of Examples 4, 9, 10, 11, and 12, when the molar concentration of palladium chloride in the mixed solution is 0.8 mM to 1.2 mM, the overpotential of the prepared catalyst is lower; according to the comparison of Examples 4, 13, 14, 15, and 16, when the etching temperature is 30°C to 50°C, the overpotential of the prepared catalyst is lower.

[0117] As shown in Table 2, in 1M KOH electrolyte, the Pd-nickel foam hydrogen evolution catalyst 2 The performance of the catalyst was improved by about 7.9% under the current density of 1000mA / cm2 in the electrolyte of 6M KOH under industrial conditions. 2 The current density was stably operated for 230 h, and the performance retention rate was potential (0 h) / potential (230 h)×100%=103.4%.

[0118] Finally, it should be noted that those skilled in the art will readily identify other embodiments of the present invention after considering the specification and practicing the invention disclosed herein. The present invention is intended to cover any variations, uses, or adaptations of the present invention that follow the general principles of the present invention and include common knowledge or customary techniques in the art not disclosed herein. The present invention is not limited to the precise structure described above and illustrated in the accompanying drawings, and various modifications and variations may be made without departing from the scope thereof. The scope of the present invention is limited solely by the appended claims.

Claims

1. A method for preparing a Pd-nickel foam hydrogen evolution catalyst, characterized in that: The following steps are involved: Performing an electro-etching-deposition process on the nickel foam using a mixed solution comprising sodium chloride and palladium chloride to obtain the Pd-nickel foam hydrogen evolution catalyst; Wherein, the electro-etching-deposition process is performed using cyclic voltammetry.

2. The preparation method of the Pd-nickel foam hydrogen evolution catalyst according to claim 1, wherein The mass percentage of the Pd in ​​the Pd-foam nickel hydrogen evolution catalyst is 0.1% to 0.5%.

3. The preparation method of the Pd-nickel foam hydrogen evolution catalyst according to claim 1 or 2, wherein The number of holes per inch of the nickel foam is 95 to 110.

4. The method for preparing the Pd-nickel foam hydrogen evolution catalyst according to any one of claims 1 to 3, wherein: Before the electro-etching-deposition process, the method further comprises: washing the nickel foam with hydrochloric acid solution, acetone and deionized water in sequence.

5. The method for preparing the Pd-nickel foam hydrogen evolution catalyst according to any one of claims 1 to 4, wherein: The temperature of the electro-etching-deposition process is 30° C. to 50° C., and the time is 8 min to 10 min.

6. The method for preparing the Pd-nickel foam hydrogen evolution catalyst according to any one of claims 1 to 5, wherein: The molar concentration of palladium chloride in the mixed solution is 0.8 mM to 1.2 mM.

7. The method for preparing the Pd-nickel foam hydrogen evolution catalyst according to any one of claims 1 to 6, wherein: The molar concentration of sodium chloride in the mixed solution is 5.8M to 6.2M.

8. A Pd-nickel foam hydrogen evolution catalyst, characterized in that The catalyst is prepared according to the method for preparing the Pd-nickel foam hydrogen evolution catalyst according to any one of claims 1 to 7.

9. A method for electrolyzing water, characterized in that: Water is electrolyzed using the Pd-nickel foam hydrogen evolution catalyst described in claim 8.

10. The method for electrolyzing water according to claim 9, characterized in that: The conditions of the electrolytic treatment include: a current density of 10 mA / cm 2 ~1000mA / cm 2 ; And / or, the electrolyte for the electrolytic treatment is a potassium hydroxide solution, and the molar concentration of the potassium hydroxide solution is 1M to 6M.

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