A hydrogen evolution electrode containing light rare earth elements and its preparation method

Abstract

This invention relates to the field of hydrogen production technology via water electrolysis, specifically to a hydrogen evolution electrode containing light rare earth elements and its preparation method. The light rare earth-containing hydrogen evolution electrode comprises a nickel foam substrate and a Ni-Se-La plating layer electroplated on the substrate surface. The plating layer comprises the following components by atomic percentage: Ni: 30-50%; Se: 20-40%; La: 30-40%. The preparation method is as follows: A clean and dry nickel foam substrate is used as the working electrode. The working electrode is immersed in an electroplating solution and electroplated at 15-30°C for at least 10 minutes. After electroplating, the electrode is cleaned and dried to obtain the product. During electroplating, the current density is controlled at 10-80 mA and the pH of the electroplating solution is 4-6. The electrode designed and prepared according to this invention was tested at 25°C in a 1 mol / L KOH solution. The obtained electrode showed a yield at 10 mA·cm⁻¹. ‑2 The overpotential at the current density can be reduced to 29mV.

Description

Technical Field

[0001] This invention relates to the field of hydrogen production technology through water electrolysis, specifically to the design of a hydrogen evolution electrode containing light rare earth elements and its preparation method. Background Technology

[0002] The increasing energy consumption and environmental pressures pose challenges to technological development. Hydrogen (H2), as a potential clean energy candidate, is valued for its high energy density (120-140 MJ·kg⁻¹). -1 Hydrogen production has attracted significant attention due to its high energy efficiency and pollution-free characteristics. Among various hydrogen production methods, the electrochemical water splitting hydrogen evolution reaction (HER) offers advantages such as stable operation, clean production, and high purity. Considering the increasing efficiency of renewable energy sources (such as hydrogen, wind, and solar power) and the high cost of precious metal catalysts, electrochemical water electrolysis HER is expected to become the mainstream hydrogen production method. Therefore, developing a cost-effective, non-precious metal-based electrocatalyst to achieve high HER performance is of great significance for water electrolysis.

[0003] Various non-noble metal electrocatalysts, such as nickel-based electrocatalysts, exhibit good chemical stability and HER activity in alkaline media. Nickel atoms possess unpaired 3d electrons in their outer shell, which readily form Ni-H adsorption bonds with the 1s orbitals of H atoms during the hydrogen evolution reaction, thereby enhancing the electrocatalytic performance of the alloy electrocatalyst. However, the electrocatalytic performance of pure nickel is limited; therefore, alloying is employed to improve its electrocatalytic performance. For example, patent CN202210948444.2 describes an attempt to use Ni-Se-Co as a hydrogen evolution electrode. This patent describes the preparation of a product using an electrodeposition process, which was tested at 25°C in a 1 mol / L KOH solution. The resulting electrode achieved an efficiency of 10 mA·cm⁻¹. -2 The overpotential at the current density is greater than 76 mV; our research group has also previously attempted to introduce Dy into Ni-Se, as detailed in "One-step galvanostatic electrodeposition of Ni-Se-Dyfilm on Ni foam for hydrogen evolution reaction in alkaline solution". In that paper, the obtained product has an overpotential greater than 76 mV at a current density of 10 mA·cm⁻¹. -2 The overpotential at the current density is approximately 72 mV. Meanwhile, a search revealed that there are few reports on techniques for preparing high-quality hydrogen evolution electrodes using Ni-Se alloys as a substrate and incorporating light rare earth elements through electrodeposition. Summary of the Invention

[0004] Based on existing technologies, and especially on the previous research of our research group, this invention is the first attempt to use light rare earth elements to further reduce the hydrogen evolution potential of the product and ensure its stability.

[0005] The present invention provides a hydrogen evolution electrode with lower overpotential and better stability after optimization.

[0006] This invention discloses a hydrogen evolution electrode containing light rare earth elements, comprising a nickel foam substrate and a Ni-Se-La plating layer electroplated on the surface of the substrate. The plating layer comprises the following components in atomic percentage: Ni: 30-50%; Se: 20-40%; La: 30-40%. In this invention, La refers to the element La.

[0007] The present invention discloses a hydrogen evolution electrode containing light rare earth elements. The Ni-Se-La coating on the substrate surface contains intermetallic compounds. The intermetallic compounds have a hexagonal structure and are arranged in a sheet-like, interlocking manner to form a micron-level structure.

[0008] As a preferred embodiment, the present invention provides a hydrogen evolution electrode containing light rare earth elements, wherein the coating comprises the following components in atomic percentage: Ni: 45-46%; Se: 24-25%; La: 30-31%.

[0009] As a further preferred embodiment, the present invention provides a hydrogen evolution electrode containing light rare earth elements, wherein the coating comprises the following components in atomic percentage: Ni: 45.4-45.6%; Se: 24.1-24.2%; La: 30.1-30.4%.

[0010] The present invention discloses a method for preparing a hydrogen evolution electrode containing light rare earth elements, comprising the following steps:

[0011] Clean and dry nickel foam is used as the working electrode. The working electrode is immersed in the electroplating solution and electroplated at 15-30°C for at least 10 minutes. After electroplating, it is cleaned and dried to obtain the product. During electroplating, the current density is controlled at 10-80 mA and the pH of the electroplating solution is controlled at 4-6. The electroplating solution is composed of the following components:

[0012] Nickel sulfate 50-140 g / L, selenium oxide 1-10 g / L, sodium chloride 25-35 g / L, boric acid 13-14 g / L, sulfosalicylic acid 13-13.5 g / L, triammonium citrate 15-25 g / L, lanthanum chloride 1-5 g / L.

[0013] Preferably, the electroplating solution consists of the following components:

[0014] Nickel sulfate 130-140 g / L, selenium oxide 5-6 g / L, sodium chloride 28-30 g / L, boric acid 13-14 g / L, sulfosalicylic acid 13-13.5 g / L, triammonium citrate 18-22 g / L, lanthanum chloride 4-5 g / L.

[0015] As a further preferred embodiment, the electroplating solution comprises the following components:

[0016] Nickel sulfate 139-140 g / L, selenium oxide 5.8-6 g / L, sodium chloride 29.5-30 g / L, boric acid 13.3-13.4 g / L, sulfosalicylic acid 13.3-13.4 g / L, triammonium citrate 19.5-22 g / L, lanthanum chloride 4.9-5 g / L.

[0017] In industrial applications, clean and dry nickel foam can be obtained by rinsing with hydrochloric acid, rinsing with anhydrous ethanol, or ultrasonic treatment followed by drying.

[0018] Preferably, the electroplating temperature is controlled at 18–22°C.

[0019] Preferably, the current density is controlled at 48–52 mA during electroplating.

[0020] Preferably, the electroplating time is controlled at 55–65 min.

[0021] In the electrodeposition process developed in this invention, the composition of the electroplating solution (including the concentration of each component) and the electroplating process parameters have a very significant impact on the deposition of Se and La.

[0022] As a further preferred embodiment, clean and dry nickel foam is used as the working electrode. The working electrode is immersed in the electroplating solution and electroplated at 20°C for 60 minutes. After electroplating, the electrode is cleaned and dried to obtain the product. During electroplating, the current density is controlled at 50 mA and the pH of the electroplating solution is controlled at 4-6. The electroplating solution is composed of the following components:

[0023] Nickel sulfate 140 g / L, selenium oxide 6 g / L, sodium chloride 30 g / L, boric acid 13.3-13.4 g / L, sulfosalicylic acid 13-13.5 g / L, triammonium citrate 18-22 g / L, lanthanum chloride 4.9-5 g / L.

[0024] The intermetallic compound formed by this invention has a hexagonal structure and is constructed in a sheet-like, layered, micron-scale manner. This allows a large amount of hydrogen to dissolve in the gaps of this hexagonal structure, thereby enabling hydrogen storage during electrolysis. The adsorbed hydrogen can generate a discharge reaction at the cathode, preventing the electrode from being oxidized and corroded by air, thus protecting the electrocatalytic activity of the electrode and enhancing the stability of the product.

[0025] This invention has revealed that light rare earth elements (LREEs) are more readily electrodeposited than heavy rare earth elements (HREEs). Even with low-concentration electroplating solutions, deposition can be completed rapidly. Furthermore, it was found that the introduction of LREEs facilitates the rapid deposition of low-concentration Se.

[0026] Advantages and positive effects of the invention

[0027] (1) The method of the present invention is simple, can be carried out at lower temperatures and lower current densities, is easy to operate and execute, and reduces the cost of precious metals;

[0028] (2) The prepared Ni-Se-La composite electrode has a low hydrogen evolution overpotential, high hydrogen evolution catalytic activity and good stability, and can be widely used in the field of alkaline water electrolysis for hydrogen production.

[0029] (3) The Ni-Se-La composite electrode developed and prepared in this invention was tested at 25°C in a 1 mol / L KOH solution. The resulting electrode was tested at 10 mA·cm⁻¹. -2 The overpotential at the current density is 29–55 mV, and after optimization, it can reach 29 mV. Attached Figure Description

[0030] Appendix Figure 1 Linear voltammetry plots of the electrodes obtained in Example 1 and Comparative Series 1;

[0031] Appendix Figure 2 The surface morphology of the Ni-Se-La electrode obtained in Example 1 is shown.

[0032] Appendix Figure 3 The EDS spectrum of the Ni-Se-La electrode obtained in Example 1 is shown below.

[0033] Appendix Figure 4 The X-ray diffraction pattern of the Ni-Se-La electrode obtained in Example 1;

[0034] Appendix Figure 5 The distribution electrolysis diagram of the Ni-Se-La electrode obtained in Example 1;

[0035] Appendix Figure 6 The image shows a long-time electrolysis diagram of the Ni-Se-La electrode obtained in Example 1.

[0036] Appendix Figure 7 The LSV curves of the Ni-Se-La electrode obtained in Example 1 before and after 5000 cyclic voltammetric scans are shown.

[0037] Figure 8 The LSV diagrams are of the electrodes obtained in Examples 2 and 3.

[0038] from Figure 1 It can be seen that the hydrogen evolution overpotential of Ni-Se-La is superior to that of Ni-Se, Ni-La, and Se-La electrodes.

[0039] from Figure 2 As can be seen, after La doping, needle-like and spherical nanoparticles appear on the electrode surface.

[0040] from Figure 3As can be seen, after electrodeposition, La and Se are deposited on Ni.

[0041] from Figure 4 As can be seen, after La doping, an amorphous structure appears on the electrode surface.

[0042] from Figure 5 The analysis shows that the electrolysis results are consistent with LSV.

[0043] from Figure 6 It can be seen that long-term electrolysis is consistent with LSV.

[0044] from Figure 7 The LSV curves before and after 5000 cycles of cyclic voltammetry scanning can be seen.

[0045] from Figure 8 The distribution of hydrogen evolution potentials of the electrodes obtained in Examples 2 and 3 can be seen. Detailed Implementation

[0046] Example 1:

[0047] (1) Pretreatment of the nickel foam substrate

[0048] Cut the purchased sheet of nickel foam into 1cm x 1cm pieces. First, wash the nickel foam three times with deionized water, then rinse it three times with anhydrous ethanol, and immerse it in a beaker containing anhydrous ethanol for sonication for 6 minutes. After sonication, remove the beaker and wash it three times with deionized water, then rinse it three times with 1mol / L hydrochloric acid, and immerse it in a beaker containing 1mol / L hydrochloric acid for sonication for 6 minutes. After sonication, wash it again with deionized water. Finally, pour in a certain amount of anhydrous ethanol and store it for later use.

[0049] (2) Preparation of electroplating solution and electrodeposition of Ni-Se-La electrode

[0050] Ni-Se-La electrodes were prepared by electrodeposition experiments using a three-electrode system on a CHI660E electrochemical workstation.

[0051] The reference electrode was a saturated calomel electrode (SCE), the working electrode was the treated nickel foam NF (1cm×1cm×0.03cm) from step (1), and the counter electrode was a graphite plate (2cm×2cm×0.5cm). The electroplating solution was prepared with the following components: nickel sulfate 140g / L, selenium dioxide 6g / L, sodium chloride 30g / L, boric acid 13.33g / L, sulfosalicylic acid 13.33g / L, triammonium citrate 20g / L, and lanthanum chloride 5g / L. The electroplating time was 60min, the electroplating temperature was 20℃, the solution pH was 4.5, and the current density was 50mA / cm². 2After the electroplating process is complete, the electroplated sheet is rinsed with deionized water, then removed and placed on paper to air dry, awaiting the next test.

[0052] The electrode coatings obtained, by atomic percentage, are: Ni: 45.51%; Se: 24.19%; La: 30.30%. (3) Hydrogen evolution performance test and structural characterization of Ni-Se-La electrode: The Ni-Se-La electrode prepared by electrodeposition experiment was tested using a three-electrode system on a CHI660E electrochemical workstation. The reference electrode was a saturated calomel electrode (SCE), the working electrode was Ni-Se-La, and the counter electrode was a graphite plate. The hydrogen evolution performance of the Ni-Se-La electrode was tested under the condition of using 1 mol / L KOH solution as electrolyte and maintaining the temperature at 25℃ in a water bath. Its linear voltammogram (LSV curve) is shown below. Figure 1 As shown, the surface morphology is as follows Figure 2 As shown, the EDS energy spectrum is as follows Figure 3 As shown.

[0053] from Figure 1 As can be seen from the results, the obtained electrode was tested at 25℃ in a 1 mol / L KOH solution, and the electrode was tested at 10 mA·cm⁻¹. -2 The overpotential at the current density is 29mV.

[0054] At 10mA·cm -2 At the specified current density, after 5000 cycles, the overpotential rise of the product is less than 2.3%.

[0055] At 30mA·cm -2 At the specified current density, after 5000 cycles, the product overpotential rise is approximately 2.4%.

[0056] At 50mA·cm -2 At the specified current density, after 5000 cycles, the product overpotential rise was approximately 2.6%. This is significantly different from the hydrogen evolution performance of existing electrodes.

[0057] Comparative Example Series 1

[0058] Ni-Se, Ni-La, and Se-La electrodes were prepared under the same conditions as in Example 1, and their linear voltammograms (LSV curves) are shown below. Figure 1 As shown.

[0059] In this invention, when preparing Ni-Se, the electroplating solution used does not contain La, and is otherwise consistent with Example 1. When preparing Ni-La, the electroplating solution used does not contain Se, and is otherwise consistent with Example 1. When preparing Se-La, the electroplating solution used does not contain nickel sulfate, and is otherwise consistent with Example 1.

[0060] Example 2:

[0061] (1) Pretreatment of the nickel foam substrate

[0062] Cut the purchased sheet of nickel foam into 1cm x 1cm pieces. First, wash the nickel foam three times with deionized water, then rinse it three times with anhydrous ethanol, and immerse it in a beaker containing anhydrous ethanol for sonication for 6 minutes. After sonication, remove the beaker and wash it three times with deionized water, then rinse it three times with 0.5mol / L hydrochloric acid, and immerse it in a beaker containing 0.5mol / L hydrochloric acid for sonication for 8 minutes. After sonication, wash it again with deionized water. Finally, pour in a certain amount of anhydrous ethanol and store it for later use.

[0063] (2) Preparation of electroplating solution and electrodeposition of Ni-Se-La electrode

[0064] A Ni-Se-La electrode was prepared by electrodeposition on a CHI660E electrochemical workstation using a three-electrode system. The reference electrode was a saturated calomel electrode (SCE), the working electrode was the prepared nickel foam NF (1cm×1cm×0.03cm) from step (1), and the counter electrode was a graphite plate (2cm×2cm×0.5cm). The electroplating solution was prepared with the following components: nickel sulfate 50g / L, selenium dioxide 1g / L, sodium chloride 30g / L, boric acid 13.33g / L, sulfosalicylic acid 13.33g / L, triammonium citrate 20g / L, and lanthanum chloride 1g / L. The electroplating time was 50min, the electroplating temperature was 15℃, and the current density was 10mA. After the electroplating process, the electroplated sheet was rinsed with deionized water, then removed and placed on paper to air dry for further testing.

[0065] The resulting electrode coatings, by atomic percentage, were: Ni: 35.21%; Se: 32.15%; La: 32.64%. (3) Hydrogen evolution performance test and structural characterization of Ni-Se-La electrode: The Ni-Se-La electrode prepared by electrodeposition experiment was tested using a three-electrode system on a CHI660E electrochemical workstation. The reference electrode was a saturated calomel electrode (SCE), the working electrode was Ni-Se-La, and the counter electrode was a graphite plate. The hydrogen evolution performance of the Ni-Se-La electrode was tested under the condition of using 1 mol / L KOH solution as electrolyte and maintaining the temperature at 25℃ in a water bath.

[0066] The obtained electrode was tested at 25℃ in a 1 mol / L KOH solution, and the obtained electrode was tested at 10 mA·cm. -2 The overpotential at the current density is 53mV.

[0067] At 10mA·cm -2 At the specified current density, after 5000 cycles, the overpotential rise of the product is less than 2.3%.

[0068] At 30mA·cm -2 At the given current density, after 5000 cycles, the product overpotential rise is approximately 2.5%.

[0069] At 50mA·cm -2 At the specified current density, after 5000 cycles, the product overpotential rise is approximately 3.1%.

[0070] Example 3:

[0071] (1) Pretreatment of the nickel foam substrate

[0072] Cut the purchased sheet of nickel foam into 1cm x 1cm pieces. First, wash the nickel foam three times with deionized water, then rinse it three times with anhydrous ethanol, and immerse it in a beaker containing anhydrous ethanol for sonication for 10 minutes. After sonication, remove the beaker and wash it three times with deionized water, then rinse it three times with 2.5 mol / L hydrochloric acid, and immerse it in a beaker containing 205 mol / L hydrochloric acid for sonication for 10 minutes. After sonication, wash it again with deionized water. Finally, pour in a certain amount of anhydrous ethanol and store it for later use.

[0073] (2) Preparation of electroplating solution and electrodeposition of Ni-Se-La electrode

[0074] A Ni-Se-La electrode was prepared by electrodeposition on a CHI660E electrochemical workstation using a three-electrode system. The reference electrode was a saturated calomel electrode (SCE), the working electrode was the prepared nickel foam NF (1cm×1cm×0.03cm) from step (1), and the counter electrode was a graphite plate (2cm×2cm×0.5cm). The electroplating solution was prepared with the following components: nickel sulfate 100g / L, selenium dioxide 5g / L, sodium chloride 30g / L, boric acid 13.33g / L, sulfosalicylic acid 13.33g / L, triammonium citrate 20g / L, and lanthanum chloride 3g / L. The electroplating time was 80min, the electroplating temperature was 30℃, and the current density was 80mA. After the electroplating process, the electroplated sheet was rinsed with deionized water, then removed and placed on paper to air dry for further testing. The resulting electrode coating, in atomic percentage, is as follows: Ni: 45.21%; Se: 21.12%; La: 33.67%.

[0075] (3) Hydrogen evolution performance testing and structural characterization of Ni-Se-La electrode

[0076] The Ni-Se-La electrode prepared by electrodeposition experiments was tested using a three-electrode system on a CHI660E electrochemical workstation. The reference electrode was a saturated calomel electrode (SCE), the working electrode was Ni-Se-La, and the counter electrode was a graphite plate. The hydrogen evolution performance of the Ni-Se-La electrode was tested under the conditions of using 1 mol / L KOH solution as the electrolyte and maintaining the temperature at 25℃ in a water bath.

[0077] The obtained electrode was tested at 25℃ in a 1 mol / L KOH solution, and the obtained electrode was tested at 10 mA·cm. -2 The overpotential at the current density is 53mV.

[0078] At 10mA·cm -2 At the specified current density, after 5000 cycles, the overpotential rise of the product is less than 2.2%.

[0079] At 30mA·cm -2 At the specified current density, after 5000 cycles, the product overpotential rise is approximately 2.4%.

[0080] At 50mA·cm -2 At the specified current density, after 5000 cycles, the product overpotential rise is approximately 2.9%.

[0081] Example 4

[0082] All other conditions are the same as in Example 1, except that:

[0083] The electroplating solution consisted of: nickel sulfate 140 g / L, selenium oxide 5 g / L, sodium chloride 30 g / L, boric acid 13.33 g / L, sulfosalicylic acid 14 g / L, triammonium citrate 20 g / L, and lanthanum chloride 3 g / L. The electroplating time was 40 min, the electroplating temperature was 30℃, and the current density was 40 mA. The resulting electrode coating, by atomic percentage, was: Ni: 42.1%; Se: 23.5%; La: 34.4%.

[0084] The obtained electrode was tested at 25℃ in a 1 mol / L KOH solution, and the obtained electrode was tested at 10 mA·cm. -2 The overpotential at the current density is 56 mV. Ni: 30–50%; Se: 20–40%; La: 30–40%

[0085] At 10mA·cm -2 At a current density of 2.5%, after 5000 cycles, the overpotential rise of the product is approximately 2.6%.

[0086] At 30mA·cm -2 At the specified current density, after 5000 cycles, the product overpotential rise is approximately 2.7%.

[0087] At 50mA·cm -2 At the specified current density, after 5000 cycles, the product overpotential rise is approximately 3.2%.

[0088] Comparative Example 2

[0089] Other conditions were the same as in Example 1, except that the electroplating solution was prepared with the following components: nickel sulfate 140 g / L, selenium oxide 5 g / L, sodium chloride 3 g / L, boric acid 1.33 g / L, sulfosalicylic acid 1.33 g / L, triammonium citrate 2 g / L, and lanthanum chloride 3 g / L. The resulting product was tested at 25°C in a 1 mol / L KOH solution, and the electrode was tested at 10 mA·cm⁻¹. -2 The overpotential at the current density is 63mV.

[0090] At 10mA·cm -2 At the specified current density, after 5000 cycles, the product overpotential rise is approximately 3.3%.

[0091] At 30mA·cm -2 At the given current density, after 5000 cycles, the product overpotential rise is approximately 3.5%.

[0092] At 50mA·cm -2 At the given current density, after 5000 cycles, the product overpotential rise is approximately 4.2%.

[0093] Comparative Example 3

[0094] Other conditions were the same as in Example 1, except that the electroplating solution was prepared with the following components: nickel sulfate 140 g / L, selenium oxide 5 g / L, sodium chloride 3 g / L, boric acid 1.33 g / L, sulfosalicylic acid 1.33 g / L, triammonium citrate 2 g / L, and lanthanum chloride 3 g / L; the electroplating time was 40 min, the electroplating temperature was 30 °C, and the current density was 40 mA. The resulting product was tested in a 1 mol / L KOH solution at 25 °C, and the electrode was tested at 10 mA·cm⁻¹. -2 The overpotential at the current density is 68mV.

[0095] At 10mA·cm -2 At the given current density, after 5000 cycles, the product overpotential rise is approximately 3.5%.

[0096] At 30mA·cm -2 At the given current density, after 5000 cycles, the product overpotential rise is approximately 3.6%.

[0097] At 50mA·cm -2At the specified current density, after 5000 cycles, the product overpotential rise is approximately 3.8%.

[0098] Comparative Example 4

[0099] (1) Pretreatment of the nickel foam substrate

[0100] Cut the purchased sheet of nickel foam into 1cm x 1cm pieces. First, wash the nickel foam three times with deionized water, then rinse it three times with anhydrous ethanol, and immerse it in a beaker containing anhydrous ethanol for sonication for 6 minutes. After sonication, remove the beaker and wash it three times with deionized water, then rinse it three times with 2mol / L hydrochloric acid, and immerse it in a beaker containing 2mol / L hydrochloric acid for sonication for 10 minutes. After sonication, wash it again with deionized water. Finally, pour in a certain amount of anhydrous ethanol and store it for later use.

[0101] (2) Preparation of electroplating solution and electrodeposition electrode

[0102] A Ni-Se-Gd electrode was prepared by electrodeposition on a CHI660E electrochemical workstation using a three-electrode system. The reference electrode was a saturated calomel electrode (SCE), the working electrode was the treated nickel foam NF (1cm×1cm×0.03cm) prepared in step (1), and the counter electrode was a graphite plate (2cm×2cm×0.5cm). The electroplating solution was prepared with the following components: nickel sulfate 160g / L, selenium oxide 1g / L, sodium chloride 30g / L, boric acid 13.33g / L, sulfosalicylic acid 14g / L, triammonium citrate 20g / L, and gadolinium chloride 1g / L. The electroplating time was 40min, the electroplating temperature was 20℃, and the current density was 40mA. After the electroplating process, the electroplated sheet was rinsed with deionized water, then removed and placed on paper to air dry for further testing.

[0103] The resulting electrode coating, by atomic percentage, is as follows: Ni: 93.5%; Se: 6.1%; Gd: 0.4%.

[0104] (3) Hydrogen evolution performance testing and structural characterization of Ni-Se-Gd electrode

[0105] The Ni-Se-Gd electrode prepared by electrodeposition experiments was tested using a three-electrode system on a CHI660E electrochemical workstation. The reference electrode was a saturated calomel electrode (SCE), the working electrode was Ni-Se-Gd, and the counter electrode was a graphite plate. The hydrogen evolution performance of the Ni-Se-Gd electrode was tested under the conditions of using 1 mol / L KOH solution as the electrolyte and maintaining the temperature at 25℃ in a water bath.

[0106] The obtained product was tested at 25°C in a 1 mol / L KOH solution, and the obtained electrode was tested at 10 mA·cm⁻¹. -2The overpotential at the current density is 71mV.

Claims

1. A hydrogen evolution electrode containing light rare earth elements, characterized in that: The hydrogen evolution electrode containing light rare earth elements comprises a nickel foam substrate and a Ni-Se-La plating layer electroplated on the surface of the substrate. The plating layer comprises the following components by atomic percentage: Ni: 30~50%; Se: 20~40%; La: 30~40%. An intermetallic compound exists in the Ni-Se-La coating electroplated on the substrate surface. The intermetallic compound has a hexagonal structure and is arranged in a sheet-like, interlocking manner to form a micron-scale structure. The hydrogen evolution electrode containing light rare earth elements is prepared by the following steps: Clean and dry nickel foam is used as the working electrode. The working electrode is immersed in the electroplating solution and electroplated at 15~30℃ for at least 10 minutes. After electroplating, it is cleaned and dried to obtain the product. The current density is controlled at 10~80mA / cm during electroplating. 2 The electroplating solution has a pH of 4-6 and is composed of the following components: Nickel sulfate 50~140g / L, selenium oxide 1~10g / L, sodium chloride 25-35g / L, boric acid 13-14g / L, sulfosalicylic acid 13-13.5g / L, triammonium citrate 15-25g / L, lanthanum chloride 1~5g / L.

2. The hydrogen evolution electrode containing light rare earth elements according to claim 1, characterized in that: The electroplating solution is composed of the following components: Nickel sulfate 130-140 g / L, selenium oxide 5-6 g / L, sodium chloride 28-30 g / L, boric acid 13-14 g / L, sulfosalicylic acid 13-13.5 g / L, triammonium citrate 18-22 g / L, lanthanum chloride 4-5 g / L.

3. The hydrogen evolution electrode containing light rare earth elements according to claim 1, characterized in that: The cleaned and dried nickel foam is obtained by rinsing with hydrochloric acid, rinsing with anhydrous ethanol, or by ultrasonic treatment, followed by drying.

4. The hydrogen evolution electrode containing light rare earth elements according to claim 1, characterized in that: The temperature is controlled at 10~30℃ during electroplating.

5. The hydrogen evolution electrode containing light rare earth elements according to claim 1, characterized in that: The current density is controlled at 48~52mA during electroplating.

6. The hydrogen evolution electrode containing light rare earth elements according to claim 1, characterized in that: The electroplating time should be controlled at 55~65 minutes.

7. The hydrogen evolution electrode containing light rare earth elements according to claim 1, characterized in that: Clean and dry nickel foam was used as the working electrode. The working electrode was immersed in the electroplating solution and electroplated at 20°C for 60 minutes. After electroplating, the electrode was cleaned and dried to obtain the product. The current density was controlled at 50 mA / cm² during electroplating. 2 The electroplating solution has a pH of 4-6 and consists of the following components. composition: Nickel sulfate 140 g / L, selenium oxide 6 g / L, sodium chloride 30 g / L, boric acid 13-14 g / L, sulfosalicylic acid 13-13.5 g / L, triammonium citrate 18-22 g / L, lanthanum chloride 4.5-5 g / L.

8. The hydrogen evolution electrode containing light rare earth elements according to claim 1, characterized in that: The obtained electrode was tested at 25 °C in a 1 mol / L KOH solution, and the obtained electrode was tested at 10 mA·cm⁻¹. −2 The overpotential at the current density is 29~55 mV.

9. A hydrogen evolution electrode containing light rare earth elements according to claim 8, characterized in that: The obtained electrode was tested at 25 °C in a 1 mol / L KOH solution, and the obtained electrode was tested at 10 mA·cm⁻¹. −2 The overpotential at the current density is 29mV.

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