Carbon-supported molybdenum-nickel-based catalyst for electrolytic water hydrogen evolution and preparation and application thereof

Abstract

The present application belongs to the technical field of material science and the technical field of electrocatalytic hydrogen production, and particularly relates to a carbon-supported molybdenum-nickel-based electrocatalyst for water electrolysis hydrogen evolution reaction in an alkaline medium and a preparation method thereof. The catalyst is prepared by a laser irradiation process, and the carbon-supported molybdenum-nickel-based electrocatalyst serves as a catalytically active center. In an alkaline medium, the catalyst can efficiently electrolyze water to produce hydrogen. The preparation process has the advantages of wide raw material sources, low price, mature and stable process, simple operation, strong controllability, and is suitable for large-scale production and industrial water electrolysis hydrogen production.

Description

Technical Field

[0001] This patented technology relates to the fields of materials science and water electrolysis catalysis, and in particular to an electrode material for efficient water splitting to produce hydrogen in alkaline environments. The material is a carbon-supported molybdenum nickel-based catalyst, and includes its manufacturing process and practical application methods. Background Technology

[0002] Against the backdrop of the global energy transition, hydrogen energy is highly regarded as an effective alternative to fossil fuels due to its widespread availability, high energy yield, and environmental purity (producing only water as a combustion byproduct with no greenhouse gas emissions). Nevertheless, the hydrogen production process remains a major obstacle limiting its wider application. Currently, industrial hydrogen production mainly relies on methods such as petroleum catalytic cracking and natural gas steam reforming, technologies that do not yet fully meet the energy strategy goal of "environmental sustainability" in terms of environmental impact and resource utilization efficiency. Fortunately, with the rapid development of renewable energy power generation technologies such as solar, wind, and geothermal energy, and the continuous improvement of power grid infrastructure, water electrolysis hydrogen production technology is gradually demonstrating its advantages in efficiency and environmental friendliness, and is considered an ideal choice for achieving industrial-scale hydrogen production. However, developing high-performance, reliable, and economically viable electrocatalysts remains a core challenge in advancing this technology.

[0003] In the field of hydrogen production through water electrolysis, electrocatalysts made of noble metals such as platinum are widely recognized for their superior performance. However, the high cost and limited availability of these materials restrict their application potential in large-scale industrial hydrogen production and hinder the widespread adoption of hydrogen production technology. Therefore, the development of cost-effective and high-performance non-noble metal electrocatalysts is crucial for promoting innovation in hydrogen production technology. Recent research progress has shown that composites of some non-noble metal elements, such as molybdenum and nickel, exhibit high activity and reliability in catalytic water splitting for hydrogen production. Despite these advances, the synthesis techniques for these materials still face challenges, such as complex preparation processes and the need for additional binders to ensure adhesion to the electrode. These factors limit their application in industrial production, making them more suitable for laboratory-scale preparation. Furthermore, the catalytic performance of low-loaded noble metal molybdenum-nickel-based materials has not yet reached a level where they can completely replace noble metal catalysts, thus their commercial application still needs improvement. Summary of the Invention

[0004] The core objective of this invention is to develop a novel water electrolysis hydrogen production electrode that uses a carbon-supported molybdenum-nickel-based catalyst as its main catalytically active component. Thanks to the wide availability and low cost of its raw materials, this electrode can achieve highly efficient catalytic reactions under alkaline conditions and maintains long-term stability of its structure and chemical properties, making it a preferred solution for industrial-scale water electrolysis hydrogen production.

[0005] Compared with existing technologies, the beneficial effects of this invention are that the carbon support scheme provided by this invention can effectively prevent the aggregation and deactivation of molybdenum-nickel active centers, ensuring the stability of long-term electrocatalytic hydrogen production. The preparation process of this invention demonstrates innovation and practicality, characterized by the maturity and stability of the technical process, coupled with ease of operation and high adjustability, making it an ideal choice for large-scale manufacturing.

[0006] This patent describes a method for preparing a carbon-supported molybdenum-nickel-based electrocatalytic hydrogen evolution catalyst, the detailed preparation steps of which include:

[0007] (1) Dissolve 0.1-20g (1-10g, 2-8g) of nickel source and 1g of molybdenum source in 100mL of solvent to form two independent solutions; stir the two solutions for 1-24h (1-15h, 2-8h) in the temperature range of 20-100℃ (20-50℃, 25-30℃);

[0008] (2) Mix the two pre-prepared solutions and purge them with an inert atmosphere (Ar, N2) gas, stir, and inject them into a closed reaction cell with a transparent light window. At the same time, pump in 10-200 mL (50-200 mL, 100-150 mL) of carbonaceous support suspension, and irradiate with laser pulses at 50-100℃ (60-90℃, 70-80℃) through the light window with a wavelength of 100-600 nm (150-500 nm, 200-400 nm), a pulse interval of 1-100 ns (1-50 ns, 10-30 ns), and a time of 1-10 h (2-7 h, 3-6 h).

[0009] (3) After laser pulse irradiation is completed, the solvent is evaporated to obtain carbon-supported molybdenum nickel-based electrolytic hydrogen evolution catalyst.

[0010] Preferably, the soluble salt of molybdenum in step (1) is one or more of ammonium dimolybdate, ammonium tetramolybdate, and ammonium paramolybdate. The soluble salt of nickel in step (1) is one or more of nickel chloride, nickel nitrate, and nickel acetate. The alcohol in step (1) is one or more of methanol and ethanol. The carbonaceous precursor in step (2) is one or more of conductive carbon black, porous carbon, and acetylene black.

[0011] The principle and mechanism of this patented technology are based on the following: Under the drive of laser irradiation, molybdenum salt, nickel salt, and carbonaceous support are mixed at the molecular level, forming nucleation and growth within the pores of the support, thereby directly forming a carbon-supported molybdenum-nickel-based electrocatalyst with specific spatial confinement in a laser irradiation atmosphere. During the laser irradiation-assisted carbon support mixing stage, the pore structure of the carbon support not only guides the formation of the molybdenum-nickel alloy but also regulates the size of the alloy particles, while simultaneously endowing the final product with a porous carbonaceous framework. This significantly increases the active surface area of ​​the electrocatalytic reaction and facilitates the rapid release of hydrogen after generation. The synergistic effect of the molybdenum and nickel precursors, the carbon source, and laser irradiation creates this unique structure, endowing the electrocatalyst with excellent hydrogen production activity and long-term stability in an alkaline environment.

[0012] This catalyst is prepared by laser irradiation and uses a carbon-supported molybdenum nickel-based electrocatalyst as the catalytic active center. It can efficiently produce hydrogen by electrolyzing water in an alkaline medium. The raw materials required for its preparation process are widely available and inexpensive. The process is mature and stable, simple to operate, and highly controllable, making it suitable for large-scale production and industrial hydrogen production by water electrolysis.

[0013] Compared with the prior art, the present invention has the following advantages:

[0014] 1. The innovative technology described above achieves the integrated fusion of four components—molybdenum, nickel, and carbon carrier—through laser irradiation, directly synthesizing size-controlled composite nickel-molybdenum-based materials. This process is highly suitable for industrial-scale production due to the readily available raw materials, low cost, mature technology, convenient operation, and strong controllability.

[0015] 2. This technology, through the combination of molybdenum and nickel and the assistance of high-energy laser irradiation, forms an electronic configuration that surpasses that of precious metals, significantly improving the catalytic efficiency of the electrocatalyst. It provides a non-precious metal carbon-supported high-efficiency catalyst as an alternative for water electrolysis to produce hydrogen under alkaline conditions.

[0016] 3. By combining porous carbon-based materials with molybdenum-nickel metal under high-energy laser irradiation, this invention avoids the use of additional coordination solvents, can precisely control the size of active components, and thus significantly enhances the structural stability of the electrocatalyst electrode. Attached Figure Description

[0017] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0018] Figure 1 Powder XRD diffraction patterns of carbon-supported molybdenum nickel materials (NiMo, NiMo-a, NiMo-b).

[0019] Figure 2 Scanning electron microscope images and particle size distribution diagrams of carbon-supported molybdenum nickel materials (NiMo, NiMo-a, NiMo-b);

[0020] in Figure 2 (a) and (b) are scanning electron microscope images and particle size distribution maps of NiMo. Figure 2 (c) and (d) are scanning electron microscope images and particle size distribution maps of NiMo-a. Figure 2 (e) and (f) are scanning electron microscope images and particle size distribution maps of NiMo-b.

[0021] Figure 3 The results show the hydrogen evolution activity of water electrolysis for carbon-supported molybdenum-nickel materials (NiMo, NiMo-a, NiMo-b) and commercial platinum-carbon (20% Pt-C) materials.

[0022] The objectives, features, and advantages of this invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0024] Figure 1 The powder XRD diffraction patterns of carbon-supported molybdenum nickel materials (NiMo, NiMo-a, NiMo-b) show obvious peaks of molybdenum nickel alloy. Figure 2 Scanning electron microscope (SEM) images and particle size distribution diagrams of carbon-supported molybdenum-nickel materials (NiMo, NiMo-a, NiMo-b) show that... Figure 2 The average particle size of NiMo is 14.98 nm, that of NiMo-a is 16.16 nm, and that of NiMo-b is 13.88 nm. Figure 3 The results of the water electrolysis hydrogen evolution activity tests on carbon-supported molybdenum-nickel materials (NiMo, NiMo-a, NiMo-b) and commercial platinum-carbon (20% Pt-C) materials show that at 100 mA / cm 2 At the specified current density, the overpotential of NiMo was 0.196 Vvs RHE, that of NiMo-a was 0.180 Vvs RHE, and that of NiMo-b was 0.189 Vvs RHE. These values ​​are closer to 0 Vvs RHE than the overpotential of commercial 20% Pt-C (-0.215 Vvs RHE), demonstrating that NiMo, NiMo-a, and NiMo-b synthesized by laser irradiation have better alkaline water electrolysis hydrogen production capabilities than commercial Pt-C catalysts.

[0025] Example 1

[0026] A method for preparing a carbon-supported molybdenum-nickel electrocatalytic hydrogen evolution material is carried out according to the following steps.

[0027] 1.32 g of nickel nitrate and 1 g of ammonium dimolybdate were dissolved separately in 100 mL of aqueous solvent to form two independent solutions. These two solutions were stirred separately for 2 h at 25 °C. Subsequently, the two pre-prepared solutions were mixed, purged with Ar, stirred, and injected into a closed reaction vessel with a transparent optical window (in this case, a quartz optical window). Simultaneously, 100 mL of conductive carbon black ethanol suspension (2 mg / mL) was pumped in, and the solution was irradiated with laser pulses at 248 nm wavelength, 5 ns pulse interval, and 1 h at 25 °C through the optical window. After laser pulse irradiation, the solvent was removed by rotary evaporation at 55 °C for 3 h to obtain a carbon-supported nickel-molybdenum-based electrolytic hydrogen evolution catalyst (NiMo).

[0028] The obtained carbon-supported molybdenum nickel-based electrolytic water evolution hydrogen catalyst was confirmed by inductively coupled plasma spectroscopy to contain 70 wt% NiMo alloy and 30 wt% carbon support.

[0029] Figure 1 The XRD pattern of the carbon-supported nickel molybdenum (NiMo) material shows significant NiMo alloy peaks, proving that NiMo is fully mixed in the channels of conductive carbon black and that the NiMo alloy is formed under laser irradiation. Figure 2 (a) and Figure 2 As can be seen in (b), the average particle size of the carbon-supported nickel molybdenum material (NiMo) is 14.98 nm, proving that the method can effectively prevent the agglomeration of the alloy and ensure the exposure of active sites.

[0030] The electrocatalytic hydrogen evolution performance of the synthesized carbon-supported nickel molybdenum (NiMo) material was evaluated using the following test procedure: a three-electrode system was used, with NiMo as the working electrode, a graphite electrode as the reverse electrode, and a saturated calomel electrode as the reference electrode. All water electrolysis tests were conducted on a Chenhua CHI660e electrochemical testing device, using a 0.1M KOH aqueous solution as the electrolyte. In the linear sweep voltammetry test, the scan rate was set to 10 mV / s, and iR compensation was applied to all electrode potentials, converting them to the relative potential of the reversible hydrogen electrode (RHE).

[0031] The process for preparing the NiMo working electrode is as follows:

[0032] (1) First, weigh 10 mg of NiMo into a weighing bottle;

[0033] (2) Then measure 100 μL of nafion solution (5% by mass) and 900 μL of isopropanol solution (water to isopropanol volume ratio of 1:2) and add them to the weighing bottle in (1);

[0034] (3) The catalyst dispersion slurry was obtained by ultrasonic dispersion at a temperature below 25°C for 1 hour.

[0035] (4) Take 5 μL of catalyst slurry and drop it onto the surface of the glassy carbon electrode (effective area is 0.19625 cm²). 2 After air drying, the catalyst loading on the electrode surface was 0.255 mg / cm³. 2 Only then can electrochemical tests be performed.

[0036] like Figure 3 As shown, NiMo exhibits extremely high hydrogen evolution activity in alkaline media, with a current density of 100 mA / cm². 2 At this point, the overpotential is 0.196V vs RHE, which is closer to 0V vs RHE than the overpotential of commercial 20wt% Pt-C (the preparation of the 20wt% Pt-C working electrode is consistent with that of NiMo working electrode) (-0.215V vs RHE). (The closer the overpotential is to 0V vs RHE, the better the performance). This proves that NiMo synthesized by laser irradiation has better alkaline water electrolysis hydrogen production capacity than commercial Pt-C catalyst.

[0037] Example 2

[0038] A method for preparing a carbon-supported molybdenum nickel-based electrocatalytic hydrogen evolution material is carried out according to the following steps.

[0039] 3.62 g of nickel nitrate and 1 g of ammonium dimolybdate were dissolved in 100 mL of aqueous solvent to form two separate solutions. These two solutions were stirred for 2 h at 25 °C. Subsequently, the two pre-prepared solutions were mixed, purged with Ar, stirred, and injected into a sealed reaction vessel with a transparent optical window (in this case, a quartz optical window). Simultaneously, 150 mL of conductive carbon black ethanol suspension (2 mg / mL) was pumped in, and the solution was irradiated with laser pulses at 340 nm wavelength, 10 ns pulse interval, and 3 h at 25 °C through the optical window. After laser pulse irradiation, the solvent was removed by rotary evaporation at 55 °C for 3 h to obtain a carbon-supported nickel-molybdenum-based electrolytic hydrogen evolution catalyst (NiMo-a).

[0040] The obtained carbon-supported molybdenum nickel-based electrolytic water evolution hydrogen evolution catalyst was confirmed by inductively coupled plasma spectroscopy to contain 62 wt% NiMo alloy and 38 wt% carbon support.

[0041] Figure 1The XRD pattern of the carbon-supported molybdenum nickel material (NiMo-a) shows significant NiMo alloy peaks, proving that NiMo is fully mixed in the channels of conductive carbon black and that the NiMo alloy is formed under laser irradiation. Figure 2 (c) and Figure 2 As can be seen in (d), the average particle size of the carbon-supported molybdenum nickel material (NiMo-a) is 16.16 nm, proving that the method can effectively prevent the agglomeration of the alloy and ensure the exposure of active sites.

[0042] The electrocatalytic hydrogen evolution performance of the synthesized carbon-supported nickel molybdenum material (NiMo-a) was evaluated using the same testing procedures as in Example 1. The working electrode was prepared using the same method as in Example 1.

[0043] like Figure 3 As shown, NiMo-a exhibits extremely high hydrogen evolution activity in alkaline media, with a current density of 100 mA / cm². 2 Under these conditions, the overpotential is 0.180V vs RHE, which is closer to 0V vs RHE than the overpotential of commercial 20wt% Pt-C (-0.215V vs RHE), demonstrating that NiMo-a synthesized by laser irradiation has better alkaline water electrolysis hydrogen production capability than commercial Pt-C catalyst.

[0044] Example 3

[0045] A method for preparing a carbon-supported molybdenum nickel-based electrocatalytic hydrogen evolution material is carried out according to the following steps.

[0046] 15.21 g of nickel nitrate and 1 g of ammonium dimolybdate were dissolved in 100 mL of aqueous solvent to form two separate solutions. These two solutions were stirred for 2 h at 25 °C. Subsequently, the two pre-prepared solutions were mixed, purged with Ar, stirred, and injected into a closed reaction vessel with a transparent optical window (in this case, a quartz optical window). Simultaneously, 200 mL of conductive carbon black ethanol suspension (2 mg / mL) was pumped in, and the solution was irradiated with laser pulses at 550 nm wavelength, 40 ns pulse interval, and 8 h at 25 °C through the optical window. After laser pulse irradiation, the solvent was removed by rotary evaporation at 55 °C for 3 h to obtain a carbon-supported nickel-molybdenum-based electrolytic hydrogen evolution catalyst (NiMo-b).

[0047] The obtained carbon-supported molybdenum nickel-based electrolytic hydrogen evolution catalyst was confirmed by inductively coupled plasma spectroscopy to contain 77 wt% NiMo alloy and 23 wt% carbon support.

[0048] Figure 1The XRD pattern of the carbon-supported nickel molybdenum material (NiMo-b) shows significant peaks of NiMo alloy, proving that NiMo is fully mixed in the channels of conductive carbon black and that NiMo alloy is formed under laser irradiation. Figure 2 (e) and Figure 2 As can be seen in (f), the average particle size of the carbon-supported molybdenum nickel material (NiMo-b) is 13.88 nm, proving that this method can effectively prevent the agglomeration of the alloy and ensure the exposure of active sites.

[0049] The electrocatalytic hydrogen evolution performance of the synthesized carbon-supported nickel molybdenum (NiMo-b) was evaluated using the same testing procedures as in Example 1. The working electrode was prepared using the same method as in Example 1.

[0050] like Figure 3 As shown, NiMo-b exhibits extremely high hydrogen evolution activity in alkaline media, with a current density of 100 mA / cm². 2 Under these conditions, the overpotential is 0.189V vs RHE, which is closer to 0V vs RHE than the overpotential of commercial 20wt% Pt-C (-0.215V vs RHE), demonstrating that NiMo-b synthesized by laser irradiation has better alkaline water electrolysis hydrogen production capability than commercial Pt-C catalyst.

[0051] While specific embodiments of the present invention have been described above, those skilled in the art should understand that these are merely illustrative examples, and various changes or modifications can be made to these embodiments without departing from the principles and essence of the present invention. The scope of protection of the present invention is defined only by the appended claims.

Claims

1. A method for preparing a carbon-supported molybdenum-nickel-based catalyst for electrolytic water hydrogen evolution, characterized by, The preparation steps are as follows: (1) 0.1-20 g of a nickel source and 1 g of a molybdenum source are respectively dissolved in 5-500 mL of a solvent to form two independent solutions; the two solutions are respectively stirred at a temperature in the range of 20-100°C for 1-24 h; the molybdenum source is a soluble salt of molybdenum, being one or more than two of ammonium dimolybdate, ammonium tetramolybdate, and ammonium paramolybdate; the nickel source is a soluble salt of nickel, being one or more than two of nickel chloride, nickel nitrate, and nickel acetate; (2) the two prepared solutions are mixed and purged with an inert atmosphere of Ar and / or N2 gas, stirred, and injected into a sealed reaction cell with a transparent light window, while pumping in 10-200 mL of a carbon carrier suspension, and irradiating with laser pulses with a wavelength of 100-600 nm, a pulse interval of 1-100 ns, and a time of 1-10 h at 50-100°C through the light window, the carbon carrier being one or more than two of conductive carbon black, porous carbon, and acetylene black; the solvent of the suspension being one or more than two of methanol, ethanol, and water, with a concentration of 0.1-10 mg / mL; (3) after laser pulse irradiation, the solvent is removed by volatilization to obtain a carbon-supported molybdenum-nickel-based electrolytic water hydrogen evolution catalyst.

2. The preparation method according to claim 1, characterized in that: in the step (1), the solvent is one or more than two of an alcohol or water, the alcohol being one or more than two of methanol or ethanol; in the step (2), the carbon carrier is one or more than two of conductive carbon black, porous carbon, and acetylene black; the solvent of the suspension is one or more than two of methanol, ethanol, and water, with a concentration of 1-10 mg / mL; the solution is subjected to rotary evaporation treatment at a temperature of 20-70°C for 1-10 h using a rotary evaporator to remove the solution.

3. A carbon-supported molybdenum-nickel-based electrolytic water hydrogen evolution catalyst prepared by any of the methods of claims 1-2.

4. The use of the carbon-supported molybdenum-nickel-based catalyst for electrolytic hydrogen evolution according to claim 3, characterized in that, An electrocatalytic hydrogen evolution electrode is prepared using the carbon-supported molybdenum-nickel-based electrolytic water hydrogen evolution catalyst as an active ingredient, and the electrocatalytic hydrogen evolution electrode is used as a cathode to electrolyze water to produce hydrogen in an alkaline medium.

5. The use according to claim 4, characterized in that, The electrocatalytic hydrogen evolution working electrode carrier is one of carbon paper, nickel foam and glassy carbon electrode, and the area is 0.001-1 cm 2 ; the carbon-supported molybdenum-nickel material loading is 0.1-5 mg / cm 2 ; the alkaline medium in the test system is one or more of potassium hydroxide or sodium hydroxide solution, and the concentration is 0.01-10 mol / L; the reference electrode and the counter electrode in the three-electrode system are one or more of Ag / AgCl, Hg / HgO, Pt sheet, Pt wire and graphite rod; the brand of the electrochemical workstation is one of Chenhua, Kost, Pine, Biologic or auto-lab; and the test results are all calibrated according to the Nernst equation reversible hydrogen electrode (RHE), wherein PH is the measured value of the alkaline medium.

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