Low platinum self-supporting electrode and electrochemical preparation method and application thereof

Abstract

The application discloses a low-platinum self-supporting electrode and an electrochemical preparation method and application thereof; a tungsten sheet and a platinum sheet are connected in parallel as an anode, a nickel sheet is used as a cathode, a one-step electrochemical reaction of anodic oxidation coupling electrodeposition is carried out in an acid electrolyte by utilizing the synergistic effect of metal electrode chemical dissolution, anodic metal electrochemical dissolution and cathodic electrodeposition, a platinum-nickel-based oxide-tungsten oxide composite self-supporting electrode is obtained at the cathode, the nickel-based oxide composition comprises nickel oxide, nickel hydroxide and hydroxyl nickel oxide, the loading amount of platinum is 0.01-0.05 mg·cm ‑2 ; the electrode composition and microstructure are regulated by controlling the reaction voltage, reaction temperature, electrolyte concentration and reaction time; the application realizes the construction of a low-platinum catalyst with high activity and high stability in a simple electrochemical process at low cost and high efficiency, and is expected to be expanded to the preparation of other noble metal and valve metal composite catalysts.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electrochemical materials, and particularly relates to a low-platinum self-supporting electrode and an electrochemical preparation method and application thereof. BACKGROUND

[0002] The platinum group noble metal has characteristics of high catalytic property, high corrosion resistance, high temperature resistance, etc., and is often used as a catalyst for various reactions and is widely applied in the fields of chemical industry, petroleum chemical industry, automobile exhaust treatment, chemical sensor, fuel cell, biology, medicine, etc. The noble metal Pt plays an important role in the process of hydrogen atom adsorption on the catalyst surface to generate adsorbed hydrogen due to the existence of empty d orbital, and can effectively reduce the overpotential of cathode and anode, and is currently recognized as the most effective hydrogen evolution catalyst. However, the scarcity and high price of Pt greatly limit its commercial large-scale application. How to reduce the platinum loading while realizing high efficient electrocatalytic activity and stability is a key problem that needs to be urgently solved.

[0003] In recent years, researchers have found a phenomenon in the test of electrocatalytic hydrogen evolution, that is, a small amount of platinum stably existing in the counter electrode will dissolve and deposit on the cathode catalyst surface, thereby improving the performance of the catalyst. After that, platinum as an uncertain factor of performance is limited to be applied in the performance evaluation of electrocatalytic hydrogen evolution, which also makes people ignore the great prospect of this process in the synthesis of low-platinum catalyst.

[0004] Such an electrochemical process of platinum "pollution" is actually a coupling step of anodic electro-oxidation and cathodic electrodeposition with platinum metal as a platinum source, which fully utilizes the anode and cathode processes of electrochemical reaction, improves the efficiency of electrochemical synthesis, and in the process, the dissolution of platinum is extremely small, which not only avoids the consumption of high-valence platinum source (such as chloroplatinic acid, etc.) in the preparation process of low-platinum catalyst, but also effectively controls the deposition amount of platinum, and has great potential in reducing the cost of catalyst and practical application. However, there are still many problems in the actual application of this method. First, this process can only use Pt, and lacks a design and synthesis method of complex inorganic catalysts. Second, this electrodeposition method mainly deposits platinum element on the cathode surface, and the binding force of Pt and the conductive substrate and the stability of the electrode surface structure are poor, thereby affecting the catalytic performance.

[0005] In addition, the existing low-platinum catalysts generally use powder catalysts, which inevitably need to use adhesives to be fixed on the conductive substrate during use, which not only increases the mass transfer resistance, but also hinders the expression of active sites, and is easy to fall off from the conductive substrate during long-time high current density electrolysis, causing the electrocatalytic performance to decrease. Therefore, how to provide a simple and economical preparation method of low-platinum catalyst with high activity and stability is a problem to be solved. SUMMARY

[0006] The present application aims to provide a low-platinum self-supporting electrode and its electrochemical preparation method and application. The present application proposes a brand-new electrochemical method of anodic oxidation coupled with electrodeposition, and the low-platinum self-supporting electrode prepared by the method has the advantages of low cost, high efficiency, stable structure and performance.

[0007] The technical solution of the present application is as follows:

[0008] A low-platinum self-supporting electrode is prepared by using tungsten sheet and platinum sheet in parallel as an anode, using a nickel sheet as a cathode (deposition carrier), and performing electrochemical anodic oxidation coupled with electrodeposition reaction in an aqueous solution of hydrochloric acid electrolyte, so as to obtain a platinum-nickel-based oxide-tungsten oxide composite self-supporting electrode on the cathode, which is the low-platinum self-supporting electrode.

[0009] The nickel-based oxide is composed of nickel oxide, nickel hydroxide and hydroxyl nickel oxide.

[0010] The nickel-based oxide is composed of nickel oxide, nickel hydroxide and hydroxyl nickel oxide.

[0011] After the electrochemical reaction, the obtained low-platinum self-supporting electrode has a porous nanocluster structure, and the loading amount of platinum is 0.01-0.05 mg·cm -2 .

[0012] The electrochemical preparation method of the low-platinum self-supporting electrode is as follows:

[0013] The tungsten sheet and the platinum sheet are connected in parallel as an anode, and the nickel sheet is used as a cathode. Under the conditions of constant voltage 10-30 V and temperature 20-90℃ in the electrolyte, the electrochemical anodic oxidation and cathode electrodeposition coupled reaction is performed for 20-250 min, and the platinum-nickel-based oxide-tungsten oxide composite self-supporting electrode is obtained on the cathode, which is the low-platinum self-supporting electrode.

[0014] The tungsten sheet, the platinum sheet and the nickel sheet are metal tungsten, metal platinum and metal nickel with a purity greater than 99%. The thickness of the tungsten sheet and the platinum sheet is between 0.05-1 mm, and the thickness of the nickel sheet is between 0.1-2 mm.

[0015] The tungsten sheet, the platinum sheet and the nickel sheet are pretreated before use as follows: ultrasonic cleaning with a mixed solution of acetone, ethanol and deionized water in a volume ratio of 3:2:5 to remove the oil on the surface, then rinsing with deionized water and drying for standby use.

[0016] The electrolyte is an aqueous solution of hydrochloric acid with a concentration of 0.5-2.5 mol / L, preferably 0.8-2 mol / L.

[0017] The preferred electrochemical reaction conditions are as follows: constant voltage 15-25 V, temperature 30-80℃, and reaction time 20-200 min.

[0018] The low-platinum self-supporting electrode can be used in the field of alcohol and amine electrocatalytic oxidation and can also be used in the field of hydrogen production by electrolysis of water.

[0019] The technical principle of the present application comprises:

[0020] The present application combines the anodic oxidation of tungsten metal and the dynamic balance of chemical dissolution and electrodeposition of cathode nickel by utilizing the trace electrochemical dissolution characteristics of anode platinum metal in an acidic electrolyte, realizes the electrochemical co-deposition of the three in the cathode, greatly improves the catalytic activity and stability of the self-supporting electrode while controlling the extremely low platinum load.

[0021] The present application has the beneficial effects that:

[0022] The present application uses metal nickel as a substrate, adopts an anodic oxidation method coupled with an electrodeposition method to prepare a low-platinum self-supporting electrode in an aqueous solution containing hydrochloric acid, and obtains low-platinum self-supporting electrodes with different structures and compositions on the metal surface by controlling the electrolyte composition, reaction temperature, oxidation voltage and oxidation time.

[0023] The present application adopts a brand-new anodic oxidation coupled with electrodeposition electrochemical method, has simple preparation process, easy operation, low reaction equipment requirement, low price, high efficiency, and the prepared platinum and nickel oxide, tungsten oxide composite self-supporting electrode cannot easily fall off, has low platinum load, high economic benefit, high electrocatalytic activity and stability, and has wide application prospect in industrial application. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 A comparison diagram of the low-platinum self-supporting electrode prepared in Example 1 (left) and the unreacted pure nickel sheet used (right).

[0025] Figure 2 A scanning electron microscope (SEM) diagram of the low-platinum self-supporting electrode prepared in Example 1.

[0026] Figure 3 A mapping diagram of the surface of the low-platinum self-supporting electrode prepared in Example 1.

[0027] Figure 4 A transmission electron microscope (TEM) diagram of the low-platinum self-supporting electrode prepared in Example 1.

[0028] Figure 5 A hydrogen evolution performance diagram of the low-platinum self-supporting electrode prepared in Example 1 in an acidic system.

[0029] Figure 6 A urea electro-oxidation performance diagram of the low-platinum self-supporting electrode prepared in Example 1 in an alkaline system.

[0030] Figure 7Scanning electron microscope (SEM) image of the low platinum self-supporting electrode prepared in Example 2.

[0031] Figure 8 Scanning electron microscope (SEM) image of the low platinum self-supporting electrode prepared in Example 3.

[0032] Figure 9 Scanning electron microscope (SEM) image of the low platinum self-supporting electrode prepared in Example 4.

[0033] Figure 10 Scanning electron microscope (SEM) image of the low platinum self-supporting electrode prepared in Example 5.

[0034] Figure 11 Scanning electron microscope (SEM) image of the low platinum self-supporting electrode prepared in Example 6.

[0035] Figure 12 Scanning electron microscope (SEM) image of the low platinum self-supporting electrode prepared in Example 7.

[0036] Figure 13 Scanning electron microscope (SEM) image of the low platinum self-supporting electrode prepared in Example 8.

[0037] Figure 14 Scanning electron microscope (SEM) image of the low platinum self-supporting electrode prepared in Example 9. DETAILED DESCRIPTION

[0038] In order to make the technical means, creative features, purposes and effects of the present application easy to understand, the present application is specifically described below in combination with embodiments and drawings.

[0039] Example 1

[0040] Tungsten and platinum sheets with a thickness of 0.085 mm were cut into a size of 2 x 1 cm 2 , and were ultrasonically cleaned in a mixed solution of acetone, ethanol and deionized water (acetone: ethanol: deionized water = 3:2:5) for 15 min, and were then rinsed with deionized water and dried to obtain the metal tungsten and platinum electrodes after removal of oil and grease; a nickel sheet (thickness 0.2 mm, size 1.5 x 2 cm 2 ) was removed of oil and grease in the same way.

[0041] Concentrated hydrochloric acid (12 mol / L) 5 mL was added to deionized water 45 mL to prepare an electrolyte, and the molar concentration of hydrochloric acid in the electrolyte was 1.2 mol / L.

[0042] The tungsten sheet and platinum sheet are connected in parallel as a double anode, the nickel sheet is a cathode, and is put into an electrolyte, the electrode spacing is kept at 2 cm, the electrolyte temperature is controlled at 50 DEG C, the reaction voltage is 20 V, and platinum, nickel-based oxide and tungsten trioxide are simultaneously deposited on the nickel sheet; the reaction time is 2.5 h, and the sample after reaction is taken out, washed, filtered and dried.

[0043] The prepared low-platinum self-supporting electrode is shown in Figure 1 . The SEM image thereof is shown in Figure 2 , the spherical particles are nano platinum, nickel-based oxide particles, and are loaded on a nano tungsten trioxide coating. The mapping image thereof is shown in Figure 3 , it can be found that four elements of platinum, nickel, tungsten and oxygen are distributed on the surface of the self-supporting electrode. The TEM image thereof is shown in Figure 4 , the lattice fringes of platinum, nickel-based oxide and tungsten oxide can be observed.

[0044] The hydrogen evolution performance thereof in an acidic system is shown in Figure 5 , it can be found that it has excellent hydrogen evolution performance and excellent stability. The electrocatalytic hydrogen evolution performance test is carried out on a Shanghai Chenhua electrochemical workstation (CHI760E), including LSV and i-t tests. A three-electrode system is adopted, the prepared self-supporting electrode is used as a working electrode, a graphite electrode is used as an auxiliary electrode, an Ag / AgCl electrode is used as a reference electrode, and the electrolyte is a 0.5 mol / L H2SO4 solution. -1

[0045] The urea electro-oxidation performance thereof in an alkaline system is shown in Figure 6 , it can be found that it has excellent urea electro-oxidation performance. The electrocatalytic urea electro-oxidation performance test is carried out on a Shanghai Chenhua electrochemical workstation (CHI760E) by CV test. A three-electrode system is adopted, the prepared self-supporting electrode is used as a working electrode, a graphite electrode is used as an auxiliary electrode, a Hg / HgO electrode is used as a reference electrode, and the electrolyte is a 1 mol / L KOH and 0.5 mol / L urea solution. -1 -1

[0046] Example 2

[0047] The tungsten sheet and platinum sheet with a thickness of 0.085 mm are cut into a size of 2x1 cm 2 , and are ultrasonically cleaned in a mixed solution of acetone, ethanol and deionized water (acetone: ethanol: deionized water = 3:2:5) for 15 min, and then are dried after being washed with deionized water. The metal tungsten and platinum electrodes after oil and fat removal are prepared; the nickel sheet (thickness 0.2 mm, size 1.5x2 cm 2 ) is removed of oil and fat in the same way.

[0048] ​​​The electrolyte was prepared by adding 5 mL of concentrated hydrochloric acid (12 mol / L) into 45 mL of deionized water, and the molar concentration of hydrochloric acid in the electrolyte was 1.2 mol / L.

[0049] The tungsten sheet and the platinum sheet were connected in parallel as the double anodes, and the nickel sheet was used as the cathode. The electrodes were placed in the electrolyte, the electrode spacing was kept at 2 cm, the temperature of the electrolyte was controlled at 50°C, and the oxidation of tungsten surface to generate tungsten trioxide was carried out at a voltage of 25 V. The platinum and nickel-based oxides and the tungsten trioxide were simultaneously deposited on the cathode. The reaction time was 150 min. The sample after the reaction was taken out, washed with deionized water, filtered, and dried to obtain the low-platinum self-supporting electrode. The SEM image thereof is shown in FIG. 2. As shown in the figure, the platinum nanoparticles are fine, and the platinum, nickel-based oxides, and tungsten trioxide are mixed together. Figure 7

[0050] Example 3

[0051] The tungsten sheet and the platinum sheet with a thickness of 0.085 mm were cut into a size of 2×1 cm 2 , and were ultrasonically cleaned in a mixed solution of acetone, ethanol, and deionized water (acetone: ethanol: deionized water = 3:2:5) for 15 min. After being washed with deionized water and dried, the metal tungsten and platinum electrodes after removal of oil and fat were obtained. The nickel sheet (thickness 0.2 mm, size 1.5×2 cm 2 ) was removed of oil and fat in the same way.

[0052] The electrolyte was prepared by adding 5 mL of concentrated hydrochloric acid (12 mol / L) into 45 mL of deionized water, and the molar concentration of hydrochloric acid in the electrolyte was 1.2 mol / L.

[0053] The tungsten sheet and the platinum sheet were connected in parallel as the double anodes, and the nickel sheet was used as the cathode. The electrodes were placed in the electrolyte, the electrode spacing was kept at 2 cm, the temperature of the electrolyte was controlled at 50°C, and the oxidation of tungsten surface to generate tungsten trioxide was carried out at a voltage of 25 V. The platinum and nickel-based oxides and the tungsten trioxide were simultaneously deposited on the cathode. The reaction time was 150 min. The sample after the reaction was taken out, washed with deionized water, filtered, and dried to obtain the low-platinum self-supporting electrode. The SEM image thereof is shown in FIG. 2. As shown in the figure, the platinum nanoparticles are fine, and the platinum, nickel-based oxides, and tungsten trioxide are mixed together. Figure 8

[0054] Example 4

[0055] The tungsten sheet and the platinum sheet with a thickness of 0.085 mm were cut into a size of 2×1 cm 2 , and were ultrasonically cleaned in a mixed solution of acetone, ethanol, and deionized water (acetone: ethanol: deionized water = 3:2:5) for 15 min. After being washed with deionized water and dried, the metal tungsten and platinum electrodes after removal of oil and fat were obtained. The nickel sheet (thickness 0.2 mm, size 1.5×2 cm 2 ) was removed of oil and fat in the same way.

[0056] ​​The electrolyte was prepared by adding 5 mL of concentrated hydrochloric acid (12 mol / L) into 45 mL of deionized water, and the molar concentration of hydrochloric acid in the electrolyte was 1.2 mol / L.

[0057] The tungsten sheet and the platinum sheet were connected in parallel as the double anodes, and the nickel sheet was the cathode. The electrodes were placed in the electrolyte, the electrode spacing was kept at 2 cm, the temperature of the electrolyte was controlled at 40℃, the reaction voltage was 20 V, the reaction time was 150 min, and the sample after the reaction was taken out, washed with deionized water, filtered and dried to obtain the low-platinum self-supporting electrode. The SEM image thereof is shown in Figure 9 As shown in the figure, the flocculent particles are nano tungsten trioxide, and the nano platinum and nickel-based oxide particles are scattered between the nano tungsten trioxide.

[0058] Example 5

[0059] The tungsten sheet and the platinum sheet with a thickness of 0.085 mm were cut into a size of 2×1 cm 2 , and were ultrasonically cleaned in a mixed solution of acetone, ethanol and deionized water (acetone: ethanol: deionized water = 3:2:5) for 15 min. After being washed with deionized water and dried, the tungsten and platinum electrodes after removal of oil and fat were obtained. The nickel sheet (thickness 0.2 mm, size 1.5×2 cm 2 ) was removed of oil and fat in the same way.

[0060] The electrolyte was prepared by adding 5 mL of concentrated hydrochloric acid (12 mol / L) into 45 mL of deionized water, and the molar concentration of hydrochloric acid in the electrolyte was 1.2 mol / L.

[0061] The tungsten sheet and the platinum sheet were connected in parallel as the double anodes, and the nickel sheet was the cathode. The electrodes were placed in the electrolyte, the electrode spacing was kept at 2 cm, the temperature of the electrolyte was controlled at 50℃, the reaction voltage was 20 V, the reaction time was 60 min, and the sample after the reaction was taken out, washed with deionized water, filtered and dried to obtain the low-platinum self-supporting electrode. The SEM image thereof is shown in Figure 10 As shown in the figure, the raised agglomerates are tungsten trioxide, and the platinum and nickel-based oxide particles are scattered between the tungsten trioxide.

[0062] Example 6

[0063] The tungsten sheet and the platinum sheet with a thickness of 0.085 mm were cut into a size of 2×1 cm 2 , and were ultrasonically cleaned in a mixed solution of acetone, ethanol and deionized water (acetone: ethanol: deionized water = 3:2:5) for 15 min. After being washed with deionized water and dried, the tungsten and platinum electrodes after removal of oil and fat were obtained. The nickel sheet (thickness 0.2 mm, size 1.5×2 cm 2 ) was removed of oil and fat in the same way.

[0064] Concentrated hydrochloric acid (12 mol / L) 5 mL was added to deionized water 45 mL to prepare an electrolyte, and the molar concentration of hydrochloric acid in the electrolyte was 1.2 mol / L.

[0065] Tungsten and platinum sheets were connected in parallel as the dual anode, and a nickel sheet (thickness 0.2 mm, size 1.5 x 2 cm 2 ) was used as the cathode. The electrodes were placed in the electrolyte with a distance of 2 cm, and the temperature of the electrolyte was controlled at 80℃. The reaction voltage was 20 V, and the reaction time was 150 min. The sample after reaction was taken out, washed with deionized water, filtered, and dried to obtain a low-platinum self-supporting electrode. The SEM image thereof is shown in Figure 11 . As shown in the figure, the large agglomerates on the surface are tungsten trioxide, and the small nanoparticles below the agglomerates are platinum and nickel-based oxide nanoparticles.

[0066] Example 7

[0067] Tungsten and platinum sheets with a thickness of 0.085 mm were cut into a size of 2 x 1 cm 2 , and were ultrasonically cleaned in a mixed solution of acetone, ethanol, and deionized water (acetone: ethanol: deionized water = 3:2:5) for 15 min. After being washed with deionized water and dried, the tungsten and platinum electrodes were obtained after removing oil and grease. A nickel sheet (thickness 0.2 mm, size 1.5 x 2 cm 2 ) was removed of oil and grease in the same way.

[0068] Concentrated hydrochloric acid (12 mol / L) 6.7 mL was added to deionized water 43.3 mL to prepare an electrolyte, and the molar concentration of hydrochloric acid in the electrolyte was 2 mol / L.

[0069] Tungsten and platinum sheets were connected in parallel as the dual anode, and a nickel sheet was used as the cathode. The electrodes were placed in the electrolyte with a distance of 2 cm, and the temperature of the electrolyte was controlled at 50℃. The reaction voltage was 20 V, and the reaction time was 150 min. The sample after reaction was taken out, washed with deionized water, filtered, and dried to obtain a low-platinum self-supporting electrode. The SEM image thereof is shown in Figure 12 . As shown in the figure, the nanocluster structure in the figure is tungsten trioxide, platinum, and nickel-based oxide particles dispersed among them.

[0070] Example 8

[0071] Tungsten and platinum sheets with a thickness of 0.085 mm were cut into a size of 2 x 1 cm 2 , and were ultrasonically cleaned in a mixed solution of acetone, ethanol, and deionized water (acetone: ethanol: deionized water = 3:2:5) for 15 min. After being washed with deionized water and dried, the tungsten and platinum electrodes were obtained after removing oil and grease. A nickel sheet (thickness 0.2 mm, size 1.5 x 2 cm 2 ) was removed of oil and grease in the same way.

[0072] Concentrated hydrochloric acid (12 mol / L) 5 mL was added to deionized water 45 mL to prepare an electrolyte, and the molar concentration of hydrochloric acid in the electrolyte was 1.2 mol / L.

[0073] Tungsten and platinum sheets were connected in parallel as double anodes, and a nickel sheet was used as a cathode. The electrodes were placed in the electrolyte, the electrode spacing was maintained at 2 cm, the electrolyte temperature was controlled at 50℃, and the reaction voltage was 20V. At the same time, platinum, nickel-based oxide, and tungsten trioxide were deposited on the tungsten sheet. The reaction time was 210 min, and the sample after the reaction was taken out, washed with deionized water, filtered, and dried to obtain a low-platinum self-supporting electrode. The SEM image thereof is shown in Figure 13 As shown in the figure, the nanoparticle structure is a composite of tungsten trioxide, platinum, and nickel-based oxide particles.

[0074] Example 9

[0075] Tungsten and platinum sheets with a thickness of 0.085 mm were cut into 2x1 cm 2 specifications, and were ultrasonically cleaned in a mixed solution of acetone, ethanol, and deionized water (acetone:ethanol:deionized water = 3:2:5) for 15 min. After washing with deionized water and drying, the metal tungsten and platinum electrodes were prepared after removing oil and grease. Nickel sheets (thickness 0.2 mm, size 1.5x2 cm 2 ) were removed from grease in the same way.

[0076] Concentrated hydrochloric acid (12 mol / L) 3.3 mL was added to deionized water 46.7 mL to prepare an electrolyte, and the molar concentration of hydrochloric acid in the electrolyte was 0.8 mol / L.

[0077] Tungsten and platinum sheets were connected in parallel as double anodes, and a nickel sheet was used as a cathode. The electrodes were placed in the electrolyte, the electrode spacing was maintained at 2 cm, the electrolyte temperature was controlled at 50℃, and the reaction voltage was 20V. At the same time, platinum, nickel-based oxide, and tungsten trioxide were deposited on the tungsten sheet. The reaction time was 210 min, and the sample after the reaction was taken out, washed with deionized water, filtered, and dried to obtain a low-platinum self-supporting electrode. The SEM image thereof is shown in Figure 14 As shown in the figure, the nanoparticle structure is a composite of tungsten trioxide, platinum, and nickel-based oxide particles.

[0078] The above embodiments are preferred cases of the present application and do not limit the protection scope of the present application.

[0079] Comparative Example

[0080] Inventive Name: A method for preparing a nano-platinum-titanium electrode, granted patent number: CN114289032B

[0081] (1) Under the condition of no water, no oxygen, nitrogen protection, a certain amount of platinum source and iron source are added into the surfactant, heated and stirred until completely dissolved to obtain a brown yellow solution; then heated to the reduction temperature at a certain heating rate, then switch the gas flow to hydrogen-nitrogen mixed gas, co-reduction for a period of time, cool to room temperature, the obtained platinum-iron nano alloy is precipitated with ethanol, dispersed with hexane, and washed alternately for many times, and finally dispersed in hexane for storage; (2) The tungsten chloride is added into anhydrous ethanol, stirred and dissolved, then the oleylamine and oleic acid are added as surface modifiers, the obtained precursor solution is added into a reaction kettle, and the solvothermal reaction is carried out at a certain temperature, after cooling to room temperature, the product is washed with cyclohexane and ethanol alternately to obtain tungsten oxide modified with long carbon chain organic molecules of oleylamine and oleic acid, i.e. tungsten oxide modified with surface organics; (3) A certain amount of platinum-iron nano alloy of step (1) is weighed and dispersed in a mixed solution of hexane and acetone, a certain amount of surface organic modified tungsten oxide of step (2) is added, ultrasonic dispersion is carried out, dried, and then inert atmosphere is introduced, treated at a certain temperature for a period of time, and the tungsten oxide supported platinum-iron nano alloy catalyst is obtained.

[0082] It can be seen that the low-platinum self-supporting electrode is prepared by the electrochemical method of anodic oxidation coupled with electrodeposition, the operation is simple, the electrolyte is ordinary hydrochloric acid solution, and no reducing agent or other reagents containing platinum, tungsten and nickel components need to be added, the metal sources are all from metal electrodes, the amount is extremely small, and the cost is lower.

[0083] The catalyst prepared by the method is a self-supporting structure electrode, compared with the powder product in the comparative example, the use of adhesives and other additives is avoided, and the catalyst has better catalytic activity and stability.

Claims

1. A low platinum self-supported electrode, characterized in that, The tungsten sheet and the platinum sheet are connected in parallel as an anode, and a nickel sheet is used as a cathode to carry out an electrochemical anodic oxidation coupling electrodeposition reaction in an electrolyte hydrochloric acid aqueous solution, so that a platinum-nickel-based oxide-tungsten oxide composite self-supporting electrode, i.e. the low-platinum self-supporting electrode, is obtained by cathode deposition.

2. The low platinum self-supported electrode of claim 1, wherein, The nickel-based oxide in the platinum-nickel-based oxide-tungsten oxide composite self-supporting electrode obtained by cathode deposition comprises nickel oxide, nickel hydroxide and hydroxyl nickel oxide.

3. The low platinum self-supported electrode of claim 1, wherein, After electrochemical reaction, the obtained low-platinum self-supporting electrode has a porous nanocluster structure, and the loading of platinum is 0.01-0.05 mg·cm -2 .

4. The electrochemical process for the preparation of a low platinum self-supported electrode according to claim 1, characterized in that, The method is as follows: The tungsten sheet and the platinum sheet are connected in parallel as an anode, and a nickel sheet is used as a cathode to carry out an electrochemical anodic oxidation coupling electrodeposition reaction in an electrolyte hydrochloric acid aqueous solution, so that a platinum-nickel-based oxide-tungsten oxide composite self-supporting electrode, i.e. the low-platinum self-supporting electrode, is obtained by cathode deposition. The electrolyte is a hydrochloric acid aqueous solution.

5. The electrochemical production method according to claim 4, characterized in that, The thickness of the tungsten sheet and the platinum sheet is between 0.05-1 mm, and the thickness of the nickel sheet is between 0.1-2 mm.

6. The electrochemical production method according to claim 4, wherein The tungsten sheet, the platinum sheet and the nickel sheet are pretreated before use by ultrasonic cleaning with a mixed solution of acetone, ethanol and deionized water in a ratio of 3:2:5 to remove grease on the surface, then rinsed with deionized water and dried for standby use.

7. The electrochemical production method according to claim 4, wherein The electrolyte is a 0.5-2.5 mol / L hydrochloric acid aqueous solution.

8. The electrochemical production method of claim 4, wherein The electrochemical reaction conditions are as follows: constant voltage 15-25 V, temperature 30-80℃, and reaction time 20-200 min.

9. The low-platinum self-supporting electrode according to claim 1 is applied in the field of alcohol and amine electrocatalytic oxidation.

10. The low-platinum self-supporting electrode according to claim 1 is applied in the field of hydrogen production by electrolysis of water.

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