High-performance low-noble-metal hydrogen evolution catalyst as well as preparation method and application thereof

Abstract

The invention discloses a high-performance low-noble-metal hydrogen evolution catalyst as well as a preparation method and application thereof, and relates to the technical field of water electrolysis hydrogen production. The preparation method of the high-performance low-noble-metal hydrogen evolution catalyst comprises the following steps: placing the porous conductive carrier in a first electrolyte containing nickel ions to carry out first-step electrochemical deposition, so that metal nickel is deposited on the surface of the porous conductive carrier; the porous conductive carrier with the metal nickel deposited on the surface is placed in air to be subjected to oxidation treatment, and a nickel oxide layer is formed on the surface of the metal nickel; and the porous conductive carrier with the nickel oxide layer is placed in a second electrolyte for second-step electrochemical deposition, metal platinum nanoparticles are deposited on the surface of the nickel oxide layer, and the second electrolyte contains soluble platinic acid or platinate. The hydrogen evolution catalyst prepared by adopting two-step electrochemical deposition has relatively high catalytic activity, and is simple in process, low in cost and suitable for batch industrial production.

Description

Technical Field

[0001] The present invention relates to the technical field of hydrogen production by electrolyzing water, and particularly relates to a high-performance low-precious-metal hydrogen evolution catalyst, a preparation method thereof, and an application thereof. Background Art

[0002] New energy storage technologies are the key technologies to promote the green transformation of today's energy. Hydrogen energy storage is considered to be the best way to store renewable energy with large capacity and long cycle due to its high energy storage density, flexible storage method, low attenuation, and no geographical restrictions. In order to popularize and apply hydrogen energy storage technology, it has become the top priority to promote the integrated development of the entire hydrogen production, storage, and utilization chain. Among them, the cost of hydrogen production accounts for the highest proportion of the total cost of hydrogen energy utilization, reaching 44%. In this case, developing low-cost and high-performance electrolytic water hydrogen production catalysts to improve hydrogen production efficiency and reduce hydrogen production cost has become one of the main challenges faced by current hydrogen energy technologies.

[0003] According to the different system working environments and the types of diaphragms used in the electrolytic cell, hydrogen production by electrolyzing water is divided into four types: alkaline electrolytic water hydrogen production, proton exchange membrane electrolytic water hydrogen production, anion exchange membrane electrolytic water hydrogen production, and solid oxide electrolytic water hydrogen production. Among them, anion exchange membrane (AEM) electrolytic water technology combines the advantages of low cost of alkaline electrolytic water, high current density of proton exchange membrane electrolytic water, and good renewable energy matching, and has received extensive attention globally. However, the problems of insufficient catalytic activity, poor stability, and high cost of existing AEM electrolytic water hydrogen production catalysts have severely restricted the practical application process of AEM electrolytic water technology. Therefore, it is urgent to develop an AEM electrolytic water hydrogen production catalyst with low cost, high activity, and high stability. Summary of the Invention

[0004] The present invention aims to provide a low-precious-metal hydrogen evolution catalyst with both low cost and high performance for hydrogen production by electrolyzing water.

[0005] The preparation method of the high-performance low-precious-metal hydrogen evolution catalyst provided by the present invention includes the following steps:

[0006] Step 1, placing a porous conductive carrier in a first electrolyte containing nickel ions for the first-step electrochemical deposition to deposit metallic nickel on the surface of the porous conductive carrier;

[0007] Step 2, placing the porous conductive carrier with metallic nickel deposited on its surface in the air for oxidation treatment to form a nickel oxide layer on the surface of the metallic nickel;

[0008] Step 3, placing the porous conductive carrier with the nickel oxide layer formed in Step 2 in a second electrolyte for the second-step electrochemical deposition to deposit platinum metal nanoparticles on the surface of the nickel oxide layer; the second electrolyte contains soluble platinum acid or platinum salt.

[0009] Optionally, the porous conductive carrier is at least one of nickel foam, cobalt foam, iron foam, carbon fiber paper, carbon cloth, and titanium mesh.

[0010] Optionally, the first electrolyte contains NiCl2 with a concentration of 0.01 - 1 M and NH4Cl with a concentration of 0.1 - 5 M.

[0011] Optionally, the parameters of the first - step electrochemical deposition include:

[0012] The current density is - 0.01 A / cm 2 ~ - 5 A / cm 2 , and the duration of electrochemical deposition is 30 s to 3600 s.

[0013] Optionally, in step 2, the oxidation treatment methods include at least one of room - temperature oxidation, oxidation in a blast drying oven, and oxidation in a tubular furnace.

[0014] Optionally, the second electrolyte contains H2PtCl6 with a concentration of 0.0001 M to 0.5 M.

[0015] Optionally, the parameters of the second - step electrochemical deposition include:

[0016] The current density is - 0.001 A / cm 2 ~ - 2 A / cm 2 , and the duration of electrochemical deposition is 5 s to 3600 s.

[0017] Optionally, in step 1, before placing the porous conductive carrier in the first electrolyte for the first - step electrochemical deposition, it further includes:

[0018] Ultrasonically cleaning the porous conductive carrier successively with absolute ethanol, 1 M HCl solution, and deionized water.

[0019] Optionally, after step 3, it further includes:

[0020] Placing the porous conductive carrier after the second - step electrochemical deposition in a vacuum drying oven for drying, and the drying temperature is 60 °C.

[0021] The high - performance low - precious - metal hydrogen - evolution catalyst prepared by the present invention is applicable to hydrogen production by electrolyzing water.

[0022] The present invention also provides an anion - exchange membrane electrolytic water device, which uses the high - performance low - precious - metal hydrogen - evolution catalyst prepared by the present invention.

[0023] The present invention has the following beneficial effects:

[0024] The present invention prepares a hydrogen evolution catalyst with a structure of Pt / NiO / Ni / porous conductive support by using a simple two-step electrochemical deposition method. This process has low requirements for the experimental environment and operation methods and is suitable for batch industrial production. Moreover, the prepared hydrogen evolution catalyst benefits from the porous structure with a high specific surface area and the synergistic catalytic effect between Pt / NiO, and has high catalytic activity. The highly dispersed Pt nanoparticles on the surface of NiO not only increase the number of active sites but also reduce the loading of the noble metal Pt. Therefore, the technical solution of the present invention can not only ensure that the hydrogen evolution catalyst has high catalytic performance but also significantly reduce the preparation cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or in the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0026] Figure 1 Field emission scanning electron microscope image of the high-performance low-noble-metal hydrogen evolution catalyst prepared in some embodiments of the present invention;

[0027] Figure 2 X-ray photoelectron spectroscopy diagram of the high-performance low-noble-metal hydrogen evolution catalyst prepared in some embodiments of the present invention;

[0028] Figure 3 Polarization curve of the high-performance low-noble-metal hydrogen evolution catalyst prepared in Example 1 of the present invention in the hydrogen evolution reaction of electrolytic water;

[0029] Figure 4 Polarization curve of the high-performance low-noble-metal hydrogen evolution catalyst prepared in Example 2 of the present invention in the hydrogen evolution reaction of electrolytic water;

[0030] Figure 5 Polarization curve of the high-performance low-noble-metal hydrogen evolution catalyst prepared in Example 3 of the present invention in the hydrogen evolution reaction of electrolytic water;

[0031] Figure 6 Polarization curve of the high-performance low-noble-metal hydrogen evolution catalyst prepared in Example 4 of the present invention in the hydrogen evolution reaction of electrolytic water;

[0032] Figure 7 Polarization curve of the high-performance low-noble-metal hydrogen evolution catalyst prepared in Example 5 of the present invention in the hydrogen evolution reaction of electrolytic water. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0033] To make the objectives, features, and advantages of the present invention more apparent and understandable, the following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the embodiments described below are only a part of the embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of the present invention.

[0034] Terms such as "first", "second", "third", "fourth", etc. (if any) in the specification and drawings of the present invention are used to distinguish similar objects and do not necessarily describe a specific order or sequence; in addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units does not necessarily limit to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products, or devices.

[0035] In the field of electrolytic water hydrogen evolution (HER) catalysts, nickel-based catalysts have become an important research direction for low-precious-metal or even non-precious-metal hydrogen evolution catalysts due to their unique electronic structure, good catalytic activity, stability, and cost advantages.

[0036] The catalytic performance of traditional nickel-based catalyst systems such as NiFe / Ni, Pt / Ni(OH)2, etc. still has a large gap compared with commercial Pt / C catalysts. The main reasons are the lack of active sites for water molecule adsorption and dissociation and the insufficient intrinsic activity of hydrogen atom recombination and desorption active sites; although a new nickel-based catalyst system, the honeycomb Pt / NiO / NF composite electrocatalyst, has been proposed in some studies, and its catalytic performance has been improved by the synergistic catalysis between Pt and NiO and the unique channel structure provided by the honeycomb NiO, its preparation method is often complex, with cumbersome operation steps and strict requirements for experimental environment, operation techniques, etc., which is not conducive to batch industrial production.

[0037] In view of the above problems, the embodiments of the present invention prepare a high-performance low-precious-metal hydrogen evolution catalyst by a simple two-step electrochemical deposition method.

[0038] The structure of the hydrogen evolution catalyst prepared in the embodiments of the present invention can be expressed as Pt / NiO / Ni / porous conductive carrier, and its preparation method includes steps 1-3:

[0039] Step 1: Place the porous conductive carrier in a first electrolyte containing nickel ions for the first-step electrochemical deposition to deposit metallic nickel on the surface of the porous conductive carrier.

[0040] In the embodiments of the present invention, the porous conductive carrier includes but is not limited to nickel foam, cobalt foam, iron foam, carbon fiber paper, carbon cloth, titanium mesh, etc.; the porous conductive carrier provides rich gas diffusion channels and proton transport channels for the catalyst finished product.

[0041] In some specific embodiments, nickel foam (NF) can be selected as the porous conductive carrier. Nickel foam has a unique open-cell network structure, and the pores are interconnected to form a large number of three-dimensional channels, so it has a high porosity and a large specific surface area.

[0042] Before the first-step electrochemical deposition, the porous conductive carrier also needs to be cleaned to provide a good deposition environment for the subsequent electrochemical deposition steps.

[0043] In some specific embodiments, the porous conductive carrier is ultrasonically cleaned successively with absolute ethanol, a 1M HCl solution, and deionized water to fully remove dirt, oxides, or other impurities on the surface of the porous conductive carrier.

[0044] In the first-step electrochemical deposition, nickel ions in the first electrolyte are reduced to metallic nickel and deposited on the surface of the porous conductive carrier.

[0045] In some specific embodiments, the first electrolyte contains NiCl2 with a concentration of 0.01~1M and NH4Cl with a concentration of 0.1~5M; NH4Cl can enhance the conductivity of the solution, and the acidic environment generated by its hydrolysis is helpful for inhibiting the hydrolysis of nickel ions, which is beneficial to obtaining a better nickel deposition layer; the first-step electrochemical deposition is a constant-current electrochemical deposition, and the parameters can be set as follows: current density -0.01A / cm 2 ~-5A / cm 2 , and the electrochemical deposition duration is 30s~3600s.

[0046] In some other embodiments, in addition to using a mixed solution of NiCl2 and NH4Cl as the first electrolyte, other electrolyte formulations suitable for electrochemically depositing metallic nickel can also be selected according to specific application requirements (such as deposition rate, porosity of the metallic nickel layer, environmental protection requirements, etc.); for example, nickel sulfate-boric acid solution, nickel sulfate-nickel chloride-boric acid solution, nickel sulfate-ammonium chloride solution, nickel sulfate-nickel chloride-ammonium chloride solution, nickel sulfate-organic carboxylic acid solution and other nickel sulfate electrolyte systems, or nickel sulfamate-boric acid solution and other nickel sulfamate electrolyte systems; surfactants or complexing agents can also be added to the first electrolyte to obtain a nickel deposition layer with special structures or properties.

[0047] Step 2, the porous conductive carrier with metallic nickel deposited on its surface is placed in the air for oxidation treatment to form a nickel oxide layer on the surface of the metallic nickel.

[0048] In this step, the oxidation treatment methods include, but are not limited to, oxidation by placing at room temperature, oxidation in a forced-air drying oven, oxidation in a tube furnace, etc.; if oxidation in a forced-air drying oven is adopted, the temperature inside the oven can be set to a suitable value within the range of 25°C to 200°C; if oxidation in a tube furnace is adopted, the temperature inside the furnace can be set to a suitable value within the range of 25°C to 400°C; in addition, plasma oxidation and chemical solution oxidation are also oxidation treatment methods that can be adopted in the embodiments of the present invention; the selection of the specific oxidation treatment process and parameters such as the temperature and duration of the oxidation treatment can be adjusted according to the actual situation.

[0049] Step 3: Place the porous conductive carrier with the nickel oxide layer formed in Step 2 into a second electrolyte for the second-step electrochemical deposition to deposit metal platinum nanoparticles on the surface of the nickel oxide layer; the second electrolyte contains soluble platinum acid or platinum salt.

[0050] In some specific embodiments, the second electrolyte contains hexachloroplatinic acid (H2PtCl6) with a concentration of 0.0001M to 0.5M; in the second-step electrochemical deposition, [PtCl6] in the second electrode solution 2− is reduced to metallic platinum and deposited on the surface of the nickel oxide layer; the second-step electrochemical deposition is a constant-current electrochemical deposition, and the parameters can be set as follows: current density -0.001A / cm 2 ~-2A / cm 2 , and the electrochemical deposition duration is 5s to 3600s.

[0051] In some other embodiments, in addition to the hexachloroplatinic acid solution, the second electrolyte can also select other solution formulations suitable for electrochemical deposition of metal platinum nanoparticles, such as hexahydroxyplatinic acid (H2Pt(OH)6), chloroplatinate (Na2PtCl6, K2PtCl6, etc.).

[0052] In some specific embodiments, after Step 3, it further includes: placing the porous conductive carrier after the second-step electrochemical deposition in a vacuum drying oven for drying, and the drying temperature is 60°C.

[0053] The structure of the high-performance low-precious-metal hydrogen evolution catalyst prepared in the embodiments of the present invention can be expressed as Pt / NiO / Ni / porous conductive carrier; when the porous conductive carrier adopted is nickel foam, the structure of the high-performance low-precious-metal hydrogen evolution catalyst prepared by the present invention is Pt / NiO / Ni / NF.

[0054] In some specific embodiments, the microstructure of the Pt / NiO / Ni / NF catalyst prepared by the present invention is as Figure 1 shown, and it is composed of Figure 1It can be seen that the overall catalyst has a three-dimensional porous structure, with the pore size ranging from dozens of nanometers to hundreds of micrometers. The nickel metal layer deposited by the first-step electrochemical deposition is a nanoporous structure, and the platinum nanoparticles deposited by the second-step electrochemical deposition are highly dispersed on the surface of the carrier.

[0055] In some specific embodiments, the X-ray photoelectron spectroscopy (XPS) of the Pt / NiO / Ni / NF catalyst prepared in the present invention is as Figure 2 shown. From Figure 2 this, it can be known that divalent Ni, zero-valent Ni, and zero-valent Pt exist in the target sample, indicating that the target sample contains three substances: Ni, NiO, and Pt. Thus, the XPS test results verify the successful synthesis of the Pt / NiO / Ni / NF catalyst.

[0056] The high-performance low-precious-metal hydrogen evolution catalyst prepared in the embodiments of the present invention uses a porous conductive material as the carrier to deposit nickel. The porous structure of the carrier and the nanoporous structure of the surface nickel metal layer can both provide rich gas diffusion channels and proton transport channels for the electrolytic water hydrogen evolution reaction. The presence of the nickel oxide layer helps to accelerate the dissociation step of water molecules during the hydrogen evolution reaction, and the presence of Pt nanoparticles helps to accelerate the recombination and desorption step of H atoms during the hydrogen evolution reaction. Thanks to the unique porous structure with a high specific surface area and the synergistic catalysis between Pt / NiO, the hydrogen evolution catalyst prepared in the embodiments of the present invention has excellent hydrogen evolution catalytic performance.

[0057] In addition, due to the highly dispersed metal platinum particles on the surface of nickel oxide, this distribution characteristic can increase the number of active sites while reducing the platinum loading in the catalyst, thereby reducing the production cost of the catalyst. At the same time, the embodiments of the present invention use a simple two-step electrochemical deposition method to prepare the Pt / NiO / Ni / porous conductive carrier hydrogen evolution catalyst. This process has low requirements for the experimental environment and operation techniques and is suitable for batch industrial production.

[0058] The high-performance low-precious-metal hydrogen evolution catalyst prepared in the embodiments of the present invention is applicable to efficient and low-cost electrolytic water hydrogen production.

[0059] Particularly, the present invention also proposes an anion exchange membrane (AEM) electrolytic water device, which at least includes an anion exchange membrane, an anode assembly, and a cathode assembly. Among them, the cathode assembly uses the high-performance low-precious-metal hydrogen evolution catalyst prepared in the above embodiments, making the anion exchange membrane electrolytic water device have the advantages of low cost, high current density, good renewable energy matching, and high hydrogen production efficiency, effectively promoting the practical application process of AEM electrolytic water technology.

[0060] Based on the above embodiments, to better illustrate the implementation manner and beneficial effects of the technical solution of the present invention, the present invention also proposes the following specific embodiments. It should be noted that the following specific embodiments are only for illustrative purposes and do not limit the protection scope of the present invention in any form.

[0061] Example 1

[0062] Step 1: Ultrasonically clean the nickel foam successively with absolute ethanol for 10 minutes, with 1M HCl solution for 5 minutes, and with deionized water for 10 minutes.

[0063] Using the nickel foam as the working electrode and the Pt sheet as the counter electrode, adopt a solution containing 0.1M NiCl2 and 2M NH4Cl (30 ml) as the electrolyte, and electro-deposit at a constant current density of -1 A / cm 2 for 200 s to deposit a nickel metal layer on the surface of the nickel foam.

[0064] Step 2: Rinse the sample obtained in Step 1 successively with deionized water and absolute ethanol, then place it in air at room temperature for 30 min for surface oxidation treatment, and then transfer the sample to a vacuum drying oven and dry it at 60 °C for 2 h.

[0065] Step 3: Using the sample dried in Step 2 as the working electrode and the Pt sheet as the counter electrode, adopt a 0.002M H2PtCl6 solution as the electrolyte (30 ml), and electro-deposit at a constant current density of -0.02 A / cm 2 for 600 s; after depositing Pt, rinse the sample successively with deionized water and absolute ethanol, and then transfer it to a vacuum drying oven and dry it at 60 °C for 2 h to obtain the target hydrogen evolution catalyst sample.

[0066] For the structural characteristics of the hydrogen evolution catalyst sample prepared in this example, refer to Figure 1 and for the X-ray photoelectron spectroscopy diagram, refer to Figure 2 .

[0067] Use an inductively coupled plasma optical emission spectrometer to test the composition of the hydrogen evolution catalyst sample. The test results are shown in Table 1. The Pt loading in the hydrogen evolution catalyst sample is only 0.825 wt%, which is much lower than the Pt loading in the currently commercially available Pt / C hydrogen production catalyst (usually ≥20 wt%).

[0068]

[0069] Table 1 Ni loading and Pt loading in the sample

[0070] The polarization curve of the hydrogen evolution catalyst sample (Pt / NiO / Ni / NF-1) in the hydrogen evolution reaction of electrolytic water was further tested, and the commercial hydrogen production Pt / C catalyst (20 wt% Pt / C / NF), the hydrogen evolution catalyst without deposited Pt (NiO / Ni / NF-1), and nickel foam (NF) were introduced as comparative samples to measure the polarization curve. The results are as Figure 3 shown.

[0071] As Figure 3 can be seen, the overpotential of the hydrogen evolution catalyst sample prepared in this example is 8.4 mV at 10 mA / cm 2 and 168 mV at 1000 mA / cm 2 . Its catalytic activity is far superior to that of the hydrogen evolution catalyst without deposited Pt (NiO / Ni / NF-1), nickel foam (NF), and the commercial hydrogen production Pt / C catalyst.

[0072] Example 2

[0073] Step 1: Ultrasonically clean the nickel foam with absolute ethanol for 10 minutes, ultrasonically clean it with 1 M HCl solution for 5 minutes, and ultrasonically clean it with deionized water for 10 minutes;

[0074] Using the nickel foam as the working electrode and the Pt sheet as the counter electrode, a solution containing 0.05 M NiCl2 and 1 M NH4Cl (30 ml) was used as the electrolyte, and electrodeposition was carried out at a constant current density of -0.5 A / cm 2 for 100 s to deposit metallic nickel on the surface of the nickel foam.

[0075] Step 2: Rinse the sample obtained in Step 1 with deionized water and absolute ethanol in sequence, then place it in air at room temperature for 30 min for surface oxidation treatment. After that, transfer the sample to a vacuum drying oven and dry it at 60 °C for 2 h.

[0076] Step 3: Using the sample dried in Step 2 as the working electrode and the Pt sheet as the counter electrode, a 0.002 M H2PtCl6 solution was used as the electrolyte (30 ml), and electrodeposition was carried out at a constant current density of -0.02 A / cm 2 for 600 s; After depositing Pt, the sample was rinsed with deionized water and absolute ethanol in sequence, and then transferred to a vacuum drying oven and dried at 60 °C for 2 h to obtain the target hydrogen evolution catalyst sample.

[0077] The polarization curve of the hydrogen evolution catalyst sample (Pt / NiO / Ni / NF-2) in the hydrogen evolution reaction of electrolytic water was tested, and the commercial hydrogen production Pt / C catalyst (20 wt% Pt / C / NF), the hydrogen evolution catalyst without deposited Pt (NiO / Ni / NF-2), and nickel foam (NF) were introduced as comparative samples to measure the polarization curve. The results are as Figure 4as shown

[0078] It can be seen from Figure 4 that the hydrogen evolution catalyst sample prepared in this example has an overpotential of 12.5 mV at 10 mA / cm 2 and an overpotential of 232 mV at 1000 mA / cm 2 . Its catalytic activity is far superior to that of the hydrogen evolution catalyst without Pt deposition (NiO / Ni / NF-2), nickel foam (NF), and commercial hydrogen production Pt / C catalyst

[0079] Example 3

[0080] Step 1: Ultrasonically clean the nickel foam in anhydrous ethanol for 10 minutes, in 1M HCl solution for 5 minutes, and in deionized water for 10 minutes

[0081] Using the nickel foam as the working electrode and the Pt sheet as the counter electrode, with an electrolyte solution containing 0.1M NiCl2 and 2M NH4Cl (30 ml), electro-deposit at a constant current density of -1 A / cm 2 for 200 s to deposit metallic nickel on the surface of the nickel foam

[0082] Step 2: Rinse the sample obtained in Step 1 with deionized water and anhydrous ethanol in sequence, and then place it in a blast drying oven at 100 °C for 1 h to complete the drying of the sample and the oxidation treatment of the surface nickel layer

[0083] Step 3: Using the sample dried in Step 2 as the working electrode and the Pt sheet as the counter electrode, with 0.002M H2PtCl6 solution as the electrolyte (30 ml), electro-deposit at a constant current density of -0.02 A / cm 2 for 600 s. After deposition of Pt, rinse the sample with deionized water and anhydrous ethanol in sequence, and then transfer it to a vacuum drying oven and dry it at 60 °C for 2 h to obtain the target hydrogen evolution catalyst sample

[0084] Test the polarization curve of the hydrogen evolution catalyst sample (Pt / NiO / Ni / NF-3) in the hydrogen evolution reaction of water electrolysis, and introduce the commercial hydrogen production Pt / C catalyst (20 wt% Pt / C / NF), the hydrogen evolution catalyst without Pt deposition (NiO / Ni / NF-3), and nickel foam (NF) as comparative samples to measure the polarization curves. The results are as Figure 5 shown

[0085] It can be seen from Figure 5 that the hydrogen evolution catalyst sample prepared in this example has an overpotential of 11.5 mV at 10 mA / cm 2 and an overpotential of 232 mV at 1000 mA / cm 2The overpotential is 215 mV, and its catalytic activity is far superior to that of the hydrogen evolution catalyst without Pt deposition (NiO / Ni / NF-3), nickel foam (NF), and commercial hydrogen production Pt / C catalyst.

[0086] Example 4

[0087] Step 1: Ultrasonically clean the nickel foam with absolute ethanol for 10 minutes, ultrasonically clean it with 1M HCl solution for 5 minutes, and ultrasonically clean it with deionized water for 10 minutes.

[0088] Using the nickel foam as the working electrode and the Pt sheet as the counter electrode, with an electrolyte solution containing 0.1M NiCl2 and 2M NH4Cl (30 ml), electro-deposit at a constant current density of -1 A / cm 2 for 200 s to deposit metallic nickel on the surface of the nickel foam.

[0089] Step 2: Rinse the sample obtained in Step 1 thoroughly with deionized water and absolute ethanol, then place it in air at room temperature for 30 min for surface oxidation treatment. After that, transfer the sample to a vacuum drying oven and dry it at 60 °C for 2 h.

[0090] Step 3: Using the sample dried in Step 2 as the working electrode and the Pt sheet as the counter electrode, with 0.005M H2PtCl6 solution as the electrolyte (30 ml), electro-deposit at a constant current density of -0.05 A / cm 2 for 900 s; rinse the sample after Pt deposition thoroughly with deionized water and absolute ethanol, then transfer it to a vacuum drying oven again and dry it at 60 °C for 2 h to obtain the target hydrogen evolution catalyst sample.

[0091] Test the polarization curve of the hydrogen evolution catalyst sample (Pt / NiO / Ni / NF-4) in the hydrogen evolution reaction of water electrolysis, and introduce the commercial hydrogen production Pt / C catalyst (20 wt% Pt / C / NF), the hydrogen evolution catalyst without Pt deposition (NiO / Ni / NF-4), and nickel foam (NF) as comparative samples to measure the polarization curves. The results are as Figure 6 shown.

[0092] It can be seen from Figure 6 that the hydrogen evolution catalyst sample prepared in this example has an overpotential of 10.5 mV at 10 mA / cm 2 and an overpotential of 172 mV at 1000 mA / cm 2 Its catalytic activity is far superior to that of the hydrogen evolution catalyst without Pt deposition (NiO / Ni / NF-4), nickel foam (NF), and commercial hydrogen production Pt / C catalyst.

[0093] Example 5

[0094] Step 1: Ultrasonically clean the nickel foam successively with absolute ethanol for 10 minutes, with 1M HCl solution for 5 minutes, and with deionized water for 10 minutes;

[0095] Using the nickel foam as the working electrode and a Pt sheet as the counter electrode, with an electrolyte solution (30 ml) containing 0.1M NiCl2 and 2M NH4Cl, electro-deposit at a constant current density of -1 A / cm 2 for 200 s to deposit metallic nickel on the surface of the nickel foam.

[0096] Step 2: Rinse the sample obtained in Step 1 successively with deionized water and absolute ethanol, then place it at room temperature in air for 30 min for surface oxidation treatment. After that, transfer the sample to a vacuum drying oven and dry it at 60 °C for 2 h.

[0097] Step 3: Using the sample dried in Step 2 as the working electrode and a Pt sheet as the counter electrode, with a 0.001M H2PtCl6 solution as the electrolyte (30 ml), electro-deposit at a constant current density of -0.01 A / cm 2 for 300 s; After depositing Pt, rinse the sample successively with deionized water and absolute ethanol, then transfer it back to the vacuum drying oven and dry it at 60 °C for 2 h to obtain the target hydrogen evolution catalyst sample.

[0098] Test the polarization curve of the hydrogen evolution catalyst sample (Pt / NiO / Ni / NF-5) in the hydrogen evolution reaction of water electrolysis, and introduce a commercially produced hydrogen evolution Pt / C catalyst (20 wt% Pt / C / NF), a hydrogen evolution catalyst without deposited Pt (NiO / Ni / NF-5), and nickel foam (NF) as comparative samples to measure the polarization curves. The results are as Figure 7 shown.

[0099] It can be seen from Figure 7 that the overpotential of the hydrogen evolution catalyst sample prepared in this example is 13.9 mV at 10 mA / cm 2 and 264 mV at 1000 mA / cm 2 . Its catalytic activity is far superior to that of the hydrogen evolution catalyst without deposited Pt (NiO / Ni / NF-5), nickel foam (NF), and the commercially produced hydrogen evolution Pt / C catalyst.

[0100] The above-described embodiments are only used to illustrate the technical solutions of the present application, and are not intended to limit them; Although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features; And these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A preparation method of a high-performance low-noble-metal hydrogen evolution catalyst, characterized in that, It includes the following steps: Step 1: Place the porous conductive carrier in a first electrolyte containing nickel ions for the first-step electrochemical deposition to deposit metallic nickel on the surface of the porous conductive carrier; Step 2: Place the porous conductive carrier with metallic nickel deposited on its surface in the air for oxidation treatment to form a nickel oxide layer on the surface of the metallic nickel; Step 3: Place the porous conductive carrier with the nickel oxide layer formed in Step 2 in a second electrolyte for the second-step electrochemical deposition to deposit platinum metal nanoparticles on the surface of the nickel oxide layer; the second electrolyte contains soluble chloroplatinic acid or platinates.

2. The preparation method of the high-performance low-noble-metal hydrogen evolution catalyst according to claim 1, characterized in that, The porous conductive carrier is at least one of nickel foam, cobalt foam, iron foam, carbon fiber paper, carbon cloth, and titanium mesh.

3. The preparation method of the high-performance low-noble-metal hydrogen evolution catalyst according to claim 1, characterized in that, The first electrolyte contains NiCl2 with a concentration of 0.01 - 1 M and NH4Cl with a concentration of 0.1 - 5 M.

4. The preparation method of the high-performance low-noble-metal hydrogen evolution catalyst according to claim 3, characterized in that The parameters of the first-step electrochemical deposition include: The current density is -0.01 A / cm 2 ~ -5 A / cm 2 , and the duration of electrochemical deposition is 30 s to 3600 s.

5. The preparation method of the high-performance low-noble-metal hydrogen evolution catalyst according to claim 1, characterized in that, In Step 2, the oxidation treatment method includes at least one of room-temperature placement oxidation, blast drying oven oxidation, and tube furnace oxidation.

6. The preparation method of the high-performance low-noble-metal hydrogen evolution catalyst according to claim 1, wherein, The second electrolyte contains H2PtCl6 with a concentration of 0.0001 M to 0.5 M.

7. The preparation method of the high-performance low-noble-metal hydrogen evolution catalyst according to claim 6, wherein The parameters of the second-step electrochemical deposition include: The current density is -0.001 A / cm 2 ~ -2 A / cm 2 , and the electrochemically deposition duration is 5 s to 3600 s.

8. A high-performance low-precious-metal hydrogen evolution catalyst prepared by the preparation method according to any one of claims 1 - 7.

9. Application of the high-performance low-precious-metal hydrogen evolution catalyst prepared by the preparation method according to any one of claims 1 - 7 in hydrogen production by electrolyzing water.

10. An anion exchange membrane electrolytic water device, characterized in that, A high-performance low-precious-metal hydrogen evolution catalyst prepared by using the preparation method according to any one of claims 1 - 7.

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