Preparation method of sulfur-rich vacancy amorphous nickel sulfide hydrogen evolution electrode

Abstract

The invention relates to the technical field of electrocatalytic hydrogen evolution, and discloses a preparation method of a sulfur-rich vacancy amorphous nickel sulfide hydrogen evolution electrode. According to the preparation method of the sulfur-rich vacancy amorphous nickel sulfide hydrogen evolution electrode, thiourea, nickel sulfide, hydrochloric acid and sodium borohydride serve as raw materials, the sulfur-rich vacancy amorphous nickel sulfide is grown on the surface of a foamed nickel carrier through a one-step electro-deposition process and sodium borohydride aqueous solution soaking, and the sulfur-rich vacancy amorphous nickel sulfide hydrogen evolution electrode is obtained. The preparation method of the sulfur-rich vacancy amorphous nickel sulfide hydrogen evolution electrode provided by the invention is environment-friendly, convenient and efficient in process, and the prepared sulfur-rich vacancy amorphous nickel sulfide hydrogen evolution electrode has relatively good hydrogen evolution performance under high current density, is fast in charge transfer, adjustable in electronic structure and low in electrochemical process energy barrier, and can be applied to the field of hydrogen evolution. The catalytic performance even exceeds that of some noble metal catalysts.

Description

Technical Field

[0001] The invention relates to the technical field of electrocatalytic hydrogen evolution, and in particular to a method for preparing a sulfur-vacancy-rich amorphous nickel sulfide hydrogen evolution electrode. Background Art

[0002] With the development of society and the acceleration of industrialization, people's demand for energy is increasing. At present, the traditional fossil fuel energy is exhausted, which has brought about a series of problems such as environmental pollution and energy crisis, seriously affecting the development of human society. Seeking a green and renewable energy system has become an urgent problem for mankind.

[0003] Hydrogen can be used as an economical fuel in electrochemical cells that power vehicles or electrical devices. The production of hydrogen fuel has led to extensive research on effective electrocatalysts for the hydrogen evolution reaction (HER). Researchers have found that transition metal catalysts have the advantages of low price and high abundance compared to precious metals. They have multiple oxidation states and diverse electronic structures, showing great prospects in large-scale industrial applications and sustainable energy conversion. The current challenge is to find more efficient and stable transition metal catalysts to replace the currently used precious metal catalysts, thereby promoting further progress in HER technology.

[0004] Among the many transition metals, nickel-based compounds, especially nickel sulfide (Ni x S y ), which has attracted extensive attention from researchers due to its structure, composition and excellent conductivity. By exploring doping, defects and strain engineering to adjust the electronic structure of nickel sulfide, the catalytic activity and stability of nickel sulfide have been effectively improved. However, the existing technology focuses too much on crystalline nickel sulfide and ignores amorphous nickel sulfide.

[0005] Based on this, a method for preparing a sulfur-vacancy-rich amorphous nickel sulfide hydrogen evolution electrode is provided, which is expected to further improve the catalytic activity and stability of nickel sulfide. Summary of the invention

[0006] The purpose of the present invention is to provide a method for preparing a sulfur-vacancy-rich amorphous nickel sulfide hydrogen evolution electrode. The method for preparing the sulfur-vacancy-rich amorphous nickel sulfide hydrogen evolution electrode is environmentally friendly, convenient and efficient. The prepared sulfur-vacancy-rich amorphous nickel sulfide hydrogen evolution electrode has good hydrogen evolution performance under high current density, fast charge transfer, adjustable electronic structure, low electrochemical process energy barrier, and catalytic performance even exceeds that of certain precious metal catalysts.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] One of the technical solutions of the present invention:

[0009] A method for preparing a sulfur-vacancy-rich amorphous nickel sulfide hydrogen evolution electrode comprises the following steps:

[0010] 1) cleaning the nickel foam to obtain a nickel foam carrier;

[0011] 2) adding nickel chloride and thiourea into water, adding hydrochloric acid solution after the nickel chloride and thiourea are completely dissolved, and mixing well to obtain an electrodeposition electrolyte;

[0012] 3) using the nickel foam carrier obtained in step 1) as a working electrode, a platinum sheet as a counter electrode, an Ag / AgCl electrode as a reference electrode, and the electrodeposition electrolyte obtained in step 2) as an electrolyte, and performing an electrodeposition treatment to generate an amorphous nickel sulfide heterojunction having a small amount of sulfur vacancies on the surface of the nickel foam carrier;

[0013] 4) placing the nickel foam carrier having a nickel sulfide amorphous heterojunction with a small amount of sulfur vacancies on the surface obtained in step 3) in a sodium borohydride solution, and allowing it to stand at room temperature to obtain the sulfur vacancy-rich amorphous nickel sulfide hydrogen evolution electrode.

[0014] Furthermore, in step 1), the cleaning is specifically as follows: firstly, the nickel foam is placed in a 3 mol / L hydrochloric acid solution, soaked for 15 minutes and then ultrasonicated for 2 minutes, then the nickel foam is placed in 95% ethanol or acetone, soaked for 15 minutes and then ultrasonicated for 2 minutes, and finally, the nickel foam is placed in ultrapure water and ultrasonicated for 5 minutes.

[0015] Furthermore, in step 1), after the nickel foam is cleaned, the nickel foam needs to be dried.

[0016] Furthermore, the drying is specifically: drying at 60° C. for 20 hours.

[0017] Furthermore, in step 2), the mass volume ratio of the nickel chloride, thiourea, water and hydrochloric acid solution is 1.19 g: 3.8 g: 50 mL: 50 μL.

[0018] Furthermore, in step 3), the electrodeposition treatment is specifically: electrodeposition at a constant potential of -1.2V to -2.0V for 50 to 1000s.

[0019] Furthermore, in step 4), the concentration of the sodium borohydride solution is 2 mol / L.

[0020] Furthermore, in step 4), the standing time is 5 to 30 minutes.

[0021] The second technical solution of the present invention:

[0022] The sulfur-rich vacancy amorphous nickel sulfide hydrogen evolution electrode prepared by the method for preparing the sulfur-rich vacancy amorphous nickel sulfide hydrogen evolution electrode.

[0023] The second technical solution of the present invention:

[0024] Application of the above-mentioned sulfur vacancy-rich amorphous nickel sulfide hydrogen evolution electrode in electrocatalytic hydrogen evolution.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] The method for preparing a sulfur vacancy-rich amorphous nickel sulfide hydrogen evolution electrode provided by the present invention has the advantages of environmental protection, convenience and high efficiency in the preparation process, and has broad prospects in the field of electrocatalytic hydrogen evolution.

[0027] The present invention provides a method for preparing a sulfur-vacancy-rich amorphous nickel sulfide hydrogen evolution electrode. During the electrodeposition process, HCl is added to the electrolyte to adjust the pH of the electrolyte, promote the electrodeposition reaction to obtain a uniform and dense deposition layer, and improve the reaction kinetics of the electrode surface. Under acidic conditions, H + The concentration increase may be related to Ni 2+ The interaction occurs on the electrode surface, which makes it easier for the active Ni site to obtain electrons, thereby improving the reaction activity. In addition, the presence of HCl will introduce some vacancies, which is beneficial to improving the hydrogen evolution performance of the sulfur vacancy-rich amorphous nickel sulfide hydrogen evolution electrode.

[0028] The method for preparing a sulfur-vacancy-rich amorphous nickel sulfide hydrogen evolution electrode provided by the present invention further increases the sulfur vacancy defects on the surface of the material by treating with a sodium borohydride aqueous solution, thereby increasing the electron density around the sulfur site, thereby promoting the strong adsorption of hydrogen intermediates, which is beneficial to improving the hydrogen evolution performance of the sulfur-vacancy-rich amorphous nickel sulfide hydrogen evolution electrode;

[0029] The method for preparing a sulfur-vacancy-rich amorphous nickel sulfide hydrogen evolution electrode provided by the present invention can prepare a sulfur-vacancy-rich amorphous nickel sulfide hydrogen evolution electrode at 2000 mA·cm -2 The overpotential is 193mV at a high current density, which is better than NF (2367mV) and NiS x -feer Sv(981mV),NiS x -poor Sv(395mV),NiS x -excess Sv (487 mV) and Pt / C (634 mV), showing the best HER activity;

[0030] The method for preparing a sulfur-vacancy-rich amorphous nickel sulfide hydrogen evolution electrode provided by the present invention has fast charge transfer, adjustable electronic structure, low electrochemical process energy barrier, and catalytic performance even exceeding that of some precious metal catalysts. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present invention. Moreover, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0032] Figure 1 The NiS prepared in Example 1 x -SEM image of rich Sv;

[0033] Figure 2 The NiS prepared in Example 1 x -TEM image of rich Sv;

[0034] Figure 3 The NiS prepared in Example 1 x -High-resolution transmission electron microscopy image of rich Sv, where the inset is the inverse fast Fourier transform image;

[0035] Figure 4 The NiS prepared in Example 1 x -rich Sv and NiS prepared in Comparative Examples 1 to 2 x -feer Sv and NiS x -Electron paramagnetic resonance spectrum of poor Sv;

[0036] Figure 5 The NiS prepared in Example 1 x -rich Sv and NiS prepared in Comparative Examples 1 to 2 x -feer Sv and NiS x - Raman spectrum of poor Sv;

[0037] Figure 6 The NiS prepared in Example 1 x -rich Sv and NiS prepared in Comparative Examples 1 to 3 x -feerSv, NiS x -poor Sv and NiS x -Excess Sv Ni 2p orbital X-ray photoelectron spectrum;

[0038] Figure 7 The NiS prepared in Example 1 x -rich Sv and NiS prepared in Comparative Examples 1 to 3 x -feerSv, NiS x -poor Sv and NiS x-Excess Sv S2p orbital X-ray photoelectron spectrum;

[0039] Figure 8 The NiS prepared in Example 1 x -rich Sv and NiS prepared in Comparative Examples 1 to 3 x -feerSv, NiS x -poor Sv and NiS x - Linear sweep voltammetry curve of excess Sv;

[0040] Fig. 9 The NiS prepared in Example 1 x -rich Sv and NiS prepared in Comparative Examples 1 to 3 x -feerSv, NiS x -poor Sv and NiS x -Nyquist plot of excess Sv;

[0041] Fig.10 The NiS prepared in Example 1 x -rich Sv and NiS prepared in Comparative Examples 1 to 3 x -feerSv, NiS x -poor Sv and NiS x -Correlation diagram of average capacitance current of excess Sv and scan rate;

[0042] Fig.11 The NiS prepared in Example 1 x -rich Sv at 1000mA·cm -2 Chronopotentiometry curves. DETAILED DESCRIPTION

[0043] Now, various exemplary embodiments of the present invention are described in detail, and this detailed description should not be considered as a limitation of the present invention, but should be understood as a more detailed description of certain aspects, characteristics and embodiments of the present invention. It should be understood that the terms described in the present invention are only for describing specific embodiments and are not used to limit the present invention.

[0044] In addition, for the numerical range in the present invention, it is understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Each smaller range between the intermediate value in any stated value or stated range and any other stated value or intermediate value in the range is also included in the present invention. The upper and lower limits of these smaller ranges can be independently included or excluded in the scope.

[0045] Unless otherwise indicated, all technical and scientific terms used herein have the same meanings as those generally understood by those skilled in the art. Although the present invention describes only preferred methods and materials, any methods and materials similar or equivalent to those described herein may also be used in the implementation or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials associated with the documents. In the event of a conflict with any incorporated document, the content of this specification shall prevail.

[0046] It will be apparent to those skilled in the art that various modifications and variations may be made to the specific embodiments of the present invention description without departing from the scope or spirit of the present invention. Other embodiments derived from the present invention description will be apparent to the skilled artisan. The present invention description and examples are exemplary only.

[0047] The words “include,” “including,” “have,” “contain,” etc. used in this document are open-ended terms, meaning including but not limited to.

[0048] In the following embodiments, a method for preparing a sulfur vacancy-rich amorphous nickel sulfide hydrogen evolution electrode comprises the following steps:

[0049] 1) washing a 1 cm×1.5 cm nickel foam to remove impurities on the surface of the nickel foam, and drying to obtain a nickel foam carrier;

[0050] The cleaning is specifically as follows: firstly, the nickel foam is placed in a 3 mol / L hydrochloric acid solution, soaked for 15 minutes and then ultrasonicated for 2 minutes, then the nickel foam is placed in 95% ethanol or acetone, soaked for 15 minutes and then ultrasonicated for 2 minutes, and finally, the nickel foam is placed in ultrapure water and ultrasonicated for 5 minutes;

[0051] The drying step specifically includes: drying at 60° C. for 20 h;

[0052] 2) Add 1.19 g nickel chloride and 3.8 g thiourea to 50 mL ultrapure water, add 50 μL hydrochloric acid solution after the nickel chloride and thiourea are completely dissolved, mix well, and obtain an electrodeposition electrolyte;

[0053] 3) Under room temperature conditions, using the nickel foam carrier obtained in step 1) as a working electrode, a platinum sheet as a counter electrode, an Ag / AgCl electrode as a reference electrode, and the electrodeposition electrolyte obtained in step 2) as an electrolyte, electroplating for 50 to 1000 seconds at a constant potential of -1.2V to -2.0V, and rinsing with ultrapure water to generate a nickel sulfide amorphous heterojunction with a small amount of sulfur vacancies on the surface of the nickel foam carrier;

[0054] 4) adding 0.38 g of sodium borohydride into 50 mL of ultrapure water to obtain a sodium borohydride solution with a concentration of 2 mol / L;

[0055] 5) placing the nickel foam support having a nickel sulfide amorphous heterojunction with a small amount of sulfur vacancies on the surface obtained in step 3) in the sodium borohydride solution obtained in step 4), allowing to stand for 5 to 30 minutes, and drying at room temperature to obtain the sulfur vacancy-rich amorphous nickel sulfide hydrogen evolution electrode.

[0056] Example 1

[0057] A sulfur vacancy-rich amorphous nickel sulfide hydrogen evolution electrode

[0058] 1) washing a 1 cm×1.5 cm nickel foam to remove impurities on the surface of the nickel foam, and drying to obtain a nickel foam carrier;

[0059] The cleaning is specifically as follows: firstly, the nickel foam is placed in a 3 mol / L hydrochloric acid solution, soaked for 15 minutes and then ultrasonicated for 2 minutes, then the nickel foam is placed in 95% ethanol, soaked for 15 minutes and then ultrasonicated for 2 minutes, and finally, the nickel foam is placed in ultrapure water and ultrasonicated for 5 minutes;

[0060] The drying step specifically includes: drying at 60° C. for 20 h;

[0061] 2) Add 1.19 g nickel chloride and 3.8 g thiourea to 50 mL ultrapure water, add 50 μL hydrochloric acid solution after the nickel chloride and thiourea are completely dissolved, mix well, and obtain an electrodeposition electrolyte;

[0062] 3) Under room temperature conditions, using the nickel foam carrier obtained in step 1) as a working electrode, a platinum sheet as a counter electrode, an Ag / AgCl electrode as a reference electrode, and the electrodeposition electrolyte obtained in step 2) as an electrolyte, electrodeposition is performed at a constant potential of -1.8 V for 600 seconds, and then rinsed with ultrapure water to generate a nickel sulfide amorphous heterojunction with a small amount of sulfur vacancies on the surface of the nickel foam carrier;

[0063] 4) adding 0.38 g of sodium borohydride into 50 mL of ultrapure water to obtain a sodium borohydride solution with a concentration of 2 mol / L;

[0064] 5) placing the nickel foam support having a nickel sulfide amorphous heterojunction with a small amount of sulfur vacancies on the surface obtained in step 3) in the sodium borohydride solution obtained in step 4), standing for 10 minutes, and drying at room temperature to obtain the sulfur vacancy-rich amorphous nickel sulfide hydrogen evolution electrode, denoted as NiS x -rich Sv.

[0065] Comparative Example 1

[0066] A nickel sulfide hydrogen evolution electrode

[0067] 1) washing a 1 cm×1.5 cm nickel foam to remove impurities on the surface of the nickel foam, and drying to obtain a nickel foam carrier;

[0068] The cleaning is specifically as follows: firstly, the nickel foam is placed in a 3 mol / L hydrochloric acid solution, soaked for 15 minutes and then ultrasonicated for 2 minutes, then the nickel foam is placed in 95% ethanol, soaked for 15 minutes and then ultrasonicated for 2 minutes, and finally, the nickel foam is placed in ultrapure water and ultrasonicated for 5 minutes;

[0069] The drying step specifically includes: drying at 60° C. for 20 h;

[0070] 2) Add 1.19 g of nickel chloride and 3.8 g of thiourea to 50 mL of ultrapure water and mix well to obtain an electrodeposition electrolyte;

[0071] 3) At room temperature, the nickel foam carrier obtained in step 1) is used as the working electrode, the platinum sheet is used as the counter electrode, the Ag / AgCl electrode is used as the reference electrode, and the electrodeposition electrolyte obtained in step 2) is used as the electrolyte. Electrodeposition is performed at a constant potential of -1.8 V for 600 s, and then rinsed with ultrapure water to obtain the nickel sulfide hydrogen evolution electrode, which is denoted as NiS x -feer Sv.

[0072] Comparative Example 2

[0073] A nickel sulfide hydrogen evolution electrode

[0074] 1) washing a 1 cm×1.5 cm nickel foam to remove impurities on the surface of the nickel foam, and drying to obtain a nickel foam carrier;

[0075] The cleaning is specifically as follows: firstly, the nickel foam is placed in a 3 mol / L hydrochloric acid solution, soaked for 15 minutes and then ultrasonicated for 2 minutes, then the nickel foam is placed in 95% ethanol, soaked for 15 minutes and then ultrasonicated for 2 minutes, and finally, the nickel foam is placed in ultrapure water and ultrasonicated for 5 minutes;

[0076] The drying step specifically includes: drying at 60° C. for 20 h;

[0077] 2) Add 1.19 g nickel chloride and 3.8 g thiourea to 50 mL ultrapure water, add 50 μL hydrochloric acid solution after the nickel chloride and thiourea are completely dissolved, mix well, and obtain an electrodeposition electrolyte;

[0078] 3) At room temperature, the nickel foam carrier obtained in step 1) is used as a working electrode, a platinum sheet is used as a counter electrode, an Ag / AgCl electrode is used as a reference electrode, and the electrodeposition electrolyte obtained in step 2) is used as an electrolyte. Electrodeposition is performed at a constant potential of -1.8 V for 600 seconds, and then rinsed with ultrapure water to generate an amorphous nickel sulfide heterojunction with a small amount of sulfur vacancies on the surface of the nickel foam carrier, i.e., the nickel sulfide hydrogen evolution electrode, denoted as NiS x -poor Sv.

[0079] Comparative Example 3

[0080] A nickel sulfide hydrogen evolution electrode

[0081] 1) washing a 1 cm×1.5 cm nickel foam to remove impurities on the surface of the nickel foam, and drying to obtain a nickel foam carrier;

[0082] The cleaning is specifically as follows: firstly, the nickel foam is placed in a 3 mol / L hydrochloric acid solution, soaked for 15 minutes and then ultrasonicated for 2 minutes, then the nickel foam is placed in 95% ethanol, soaked for 15 minutes and then ultrasonicated for 2 minutes, and finally, the nickel foam is placed in ultrapure water and ultrasonicated for 5 minutes;

[0083] The drying step specifically includes: drying at 60° C. for 20 h;

[0084] 2) Add 1.19 g nickel chloride and 3.8 g thiourea to 50 mL ultrapure water, add 50 μL hydrochloric acid solution after the nickel chloride and thiourea are completely dissolved, mix well, and obtain an electrodeposition electrolyte;

[0085] 3) Under room temperature conditions, using the nickel foam carrier obtained in step 1) as a working electrode, a platinum sheet as a counter electrode, an Ag / AgCl electrode as a reference electrode, and the electrodeposition electrolyte obtained in step 2) as an electrolyte, electrodeposition is performed at a constant potential of -1.8 V for 600 seconds, and then rinsed with ultrapure water to generate a nickel sulfide amorphous heterojunction with a small amount of sulfur vacancies on the surface of the nickel foam carrier;

[0086] 4) adding 1.9 g of sodium borohydride into 50 mL of ultrapure water to obtain a sodium borohydride solution with a concentration of 1 mol / L;

[0087] 5) placing the nickel foam support having a nickel sulfide amorphous heterojunction with a small amount of sulfur vacancies on the surface obtained in step 3) in the sodium borohydride solution obtained in step 4), allowing to stand for 10 minutes, and drying at room temperature to obtain the nickel sulfide hydrogen evolution electrode, denoted as NiS x -excess Sv.

[0088] Effect verification

[0089] Example 1: NiS preparedx -rich Sv scanning electron microscope image Figure 1 As shown;

[0090] Depend on Figure 1 It can be seen that NiS x The scanning electron microscopy images of -rich Sv show a typical three-dimensional nanosphere morphology, which has a high specific surface area and promotes mass transfer to improve HER kinetics.

[0091] Example 1: NiS prepared x -rich Sv transmission electron microscopy image Figure 2 As shown;

[0092] Depend on Figure 2 It can be seen that NiS x -rich Sv irregular nanospheres with a large number of nanoparticles attached to the surface.

[0093] Example 1: NiS prepared x -rich Sv high-resolution transmission electron microscopy image Figure 3 As shown, the inset is the inverse fast Fourier transform image;

[0094] Depend on Figure 3 It can be seen that NiS x -rich Sv is an amorphous short-range ordered structure, and Ni can be observed through the fast Fourier inverse transform image 3 S 2 (202) crystal plane, with a lattice spacing of 0.201 nm, has very weak crystallinity.

[0095] Example 1: NiS prepared x -rich Sv and NiS prepared in Comparative Examples 1 to 2 x -feer Sv and NiS x The electron paramagnetic resonance spectrum of -poor Sv is as follows Figure 4 As shown;

[0096] Depend on Figure 4 It can be seen that in the electron paramagnetic resonance spectrum, there is a strong S vacancy signal peak at g = 2.003, which indicates that NiS x The abundant S vacancies on the surface of -rich Sv are generated during the electrochemical deposition process and sodium borohydride solution immersion, which is beneficial to transfer electrons to the metal active centers to enhance the catalytic activity.

[0097] Example 1: NiS prepared x -rich Sv and NiS prepared in Comparative Examples 1 to 2 x -feer Sv and NiS x-poor Sv Raman spectrum is as follows Figure 5 As shown;

[0098] Depend on Figure 5 It can be seen that in the Raman spectrum, 306.92cm -1 、325.95cm -1 Ni 3 S 2 The characteristic peaks of NiS x -rich Sv's Ni 3 S 2 The peak intensity is stronger, which confirms that the valence state of Ni is reduced.

[0099] Example 1: NiS prepared x -rich Sv and NiS prepared in Comparative Examples 1 to 3 x -feerSv, NiS x -poor Sv and NiS x -excess Sv Ni 2p orbital X-ray photoelectron spectrum as shown Figure 6 As shown;

[0100] Depend on Figure 6 It can be seen that the Ni 2p spectrum at 855.53eV is Ni 2+ and two Shakeup satellite peaks (identified as “Sat”), which are clearly related to NiS x -feer Sv (855.93 eV), more sulfur vacancies are introduced with the extension of etching time, causing Ni 2p to move 0.4 eV toward lower binding energy, which means that the increase in sulfur vacancy concentration has a significant regulatory effect on the electronic structure of Ni 2p, making it easier for active Ni sites to obtain electrons, thereby improving the hydrogen evolution performance.

[0101] Example 1: NiS prepared x -rich Sv and NiS prepared in Comparative Examples 1 to 3 x -feerSv, NiS x -poor Sv and NiS x -excess Sv S2p orbital X-ray photoelectron spectrum is as follows Figure 7 As shown;

[0102] Depend on Figure 7 It can be seen that the S2p spectrum has four peaks, among which the two peaks at 162.73eV and 164.11eV are respectively attributed to the S element 2p 3 / 2 and 2p 1 / 2, and there are two Shakeup satellite peaks (identified as "Sat") at 168.48eV and 107.07eV; the S2 corresponding to the low binding energy p1 / 2 The peak is related to sulfur vacancies, and as the number of vacancies increases, S2p moves toward lower binding energy.

[0103] Example 1: NiS prepared x -rich Sv and NiS prepared in Comparative Examples 1 to 3 x -feerSv, NiS x -poor Sv and NiS x -excess Sv linear sweep voltammetry curve is shown in Figure 8 As shown;

[0104] Depend on Figure 8 It can be seen that NiS x -rich Sv at 2000mA·cm -2 The overpotential is 193mV at a high current density, which is better than NF (2367mV) and NiS x -feer Sv(981mV),NiS x -poor Sv(395mV),NiS x -excess Sv (487 mV) and Pt / C (634 mV), showing the best HER activity.

[0105] Example 1: NiS prepared x -rich Sv and NiS prepared in Comparative Examples 1 to 3 x -feerSv, NiS x -poor Sv and NiS x The Nyquist curve of -excess Sv is as follows Fig. 9 As shown;

[0106] Depend on Fig. 9 It can be seen that NiS x -rich Sv has a higher charge transfer resistance than NiS x -feer Sv, NiS x -poor Sv and NiS x -excess Sv charge transfer resistance is small.

[0107] Example 1: NiS prepared x -rich Sv and NiS prepared in Comparative Examples 1 to 3 x -feerSv, NiS x -poor Sv and NiS x-Excess Sv average capacitance current and scan rate correlation diagram as shown in Fig.10 As shown;

[0108] Depend on Fig.10 It can be seen that NiS x -rich Sv electrochemical double layer capacitance (164.4mF·cm -2 ) is higher than NiS x -feer Sv(65.6mF·cm -2 )、NiS x -poor Sv(32.5mF·cm -2 ) and NiS x -excess Sv(108.1mF·cm -2 ) of the electrochemical double layer capacitance, which indicates that NiS x -rich Sv electrocatalysts have larger active areas.

[0109] Example 1: NiS prepared x -rich Sv at 1000mA·cm -2 The chronopotential curve is shown in Fig.11 As shown;

[0110] Depend on Fig.11 It can be seen that at 1000mA·cm -2 The chronopotentiometry curves can detect NiS x The stability of -rich Sv in actual water electrolysis reached 1000mA·cm during the 100h test period. -2 The required potential change is negligible, which indicates that NiS x -rich Sv has excellent stability.

[0111] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A method for preparing a sulfur vacancy-rich amorphous nickel sulfide hydrogen evolution electrode, characterized in that: The following steps are involved: 1) cleaning the nickel foam to obtain a nickel foam carrier; 2) adding nickel chloride and thiourea into water, adding hydrochloric acid solution after the nickel chloride and thiourea are completely dissolved, and mixing well to obtain an electrodeposition electrolyte; 3) using the nickel foam carrier obtained in step 1) as a working electrode, a platinum sheet as a counter electrode, an Ag / AgCl electrode as a reference electrode, and the electrodeposition electrolyte obtained in step 2) as an electrolyte, and performing an electrodeposition treatment to generate an amorphous nickel sulfide heterojunction having a small amount of sulfur vacancies on the surface of the nickel foam carrier; 4) placing the nickel foam carrier having a nickel sulfide amorphous heterojunction with a small amount of sulfur vacancies on the surface obtained in step 3) in a sodium borohydride solution, and allowing it to stand at room temperature to obtain the sulfur vacancy-rich amorphous nickel sulfide hydrogen evolution electrode.

2. The method for preparing a sulfur vacancy-rich amorphous nickel sulfide hydrogen evolution electrode according to claim 1, characterized in that: In step 1), the cleaning is specifically as follows: firstly, the nickel foam is placed in a 3 mol / L hydrochloric acid solution, soaked for 15 minutes and then ultrasonicated for 2 minutes, then the nickel foam is placed in 95% ethanol or acetone, soaked for 15 minutes and then ultrasonicated for 2 minutes, and finally, the nickel foam is placed in ultrapure water and ultrasonicated for 5 minutes.

3. The method for preparing a sulfur vacancy-rich amorphous nickel sulfide hydrogen evolution electrode according to claim 1, characterized in that: In step 1), after cleaning the nickel foam, the nickel foam needs to be dried.

4. The method for preparing a sulfur vacancy-rich amorphous nickel sulfide hydrogen evolution electrode according to claim 3, characterized in that: The drying is specifically: drying at 60° C. for 20 hours.

5. The method for preparing a sulfur vacancy-rich amorphous nickel sulfide hydrogen evolution electrode according to claim 1, characterized in that: In step 2), the mass volume ratio of the nickel chloride, thiourea, water and hydrochloric acid solution is 1.19 g: 3.8 g: 50 mL: 50 μL.

6. The method for preparing a sulfur vacancy-rich amorphous nickel sulfide hydrogen evolution electrode according to claim 1, characterized in that: In step 3), the electrodeposition treatment is specifically: electrodeposition at a constant potential of -1.2V to -2.0V for 50 to 1000s.

7. The method for preparing a sulfur vacancy-rich amorphous nickel sulfide hydrogen evolution electrode according to claim 1, characterized in that: In step 4), the concentration of the sodium borohydride solution is 2 mol / L.

8. The method for preparing a sulfur vacancy-rich amorphous nickel sulfide hydrogen evolution electrode according to claim 1, characterized in that: In step 4), the standing time is 5 to 30 minutes.

9. A sulfur-vacancy-rich amorphous nickel sulfide hydrogen evolution electrode prepared by the method for preparing a sulfur-vacancy-rich amorphous nickel sulfide hydrogen evolution electrode according to any one of claims 1 to 8.

10. Use of the sulfur vacancy-rich amorphous nickel sulfide hydrogen evolution electrode as claimed in claim 9 in electrocatalytic hydrogen evolution.

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