A catalytic material, a preparation method thereof and application thereof in electrocatalytic selective oxidation of alcohols assisted hydrogen production

Abstract

The application relates to the field of organic electrochemistry, in particular to a catalytic material, a preparation method thereof and application of the catalytic material in electrocatalytic selective oxidation of alcohols to assist hydrogen production. The application synthesizes a high-efficiency stable bimetallic doped nickel-based metal phosphide catalytic material through a simple hydrothermal and phosphorization method, optimizes the electronic structure of a catalyst surface, and further increases active sites of the catalyst. The catalytic material presents a relatively rough sheet structure, forms a three-dimensional net-like pore structure, enhances the diffusion capacity of ions and electrons at an interface, effectively increases the active surface area in a contact area between an electrode and an electrolyte, and thus improves the catalytic efficiency and kinetic performance. The catalytic material is used in electrocatalytic oxidation of alcohols to assist hydrogen evolution, is helpful to renewable energy driven electrocatalytic hydrogen evolution reaction, greatly reduces hydrogen production energy consumption and improves hydrogen production rate, and simultaneously catalyzes directional oxidation of alcohols to obtain acid and other high-value-added chemicals.

Description

Technical Field

[0001] This invention relates to the field of organic electrochemistry, specifically to a catalytic material, its preparation method, and its application in the selective oxidation of alcohols to assist hydrogen production via electrocatalysis. Background Technology

[0002] Since the Industrial Revolution, with rapid economic development and social progress, human demand for energy has increased dramatically. The extensive use of fossil fuels such as coal has led to a series of negative consequences, including the greenhouse effect and environmental pollution. Currently, my country's energy consumption is highly dependent on fossil fuels, and its carbon emissions are substantial. Therefore, vigorously developing technology has become a top priority for industries such as steel, petroleum, and chemicals.

[0003] Hydrogen has a high energy density (140 MJ / kg) and is indispensable as a clean and efficient energy source in decarbonization and sustainable energy systems. Modern hydrogen production technologies are mainly divided into three categories: clean energy water electrolysis, fossil fuel reforming, and industrial by-product hydrogen production. Electrocatalytic water splitting is known as "green hydrogen" because it produces no carbon emissions. Green hydrogen technology is becoming an important technological foundation for achieving decarbonization goals and will be an effective solution to the intermittency problem of renewable energy.

[0004] Currently, hydrogen production through water electrolysis faces two main problems. First, the cost is too high. In the electrocatalytic water splitting process, the oxygen evolution reaction (OER) at the anode and the hydrogen evolution reaction (HER) at the cathode produce oxygen (O2) and hydrogen (H2), respectively. The best-performing catalysts for HER are currently Pt-based catalysts; the best-performing catalysts for OER are noble metal oxides such as Ru and Ir. Noble metal materials are very expensive, so much research in recent years has focused on non-noble metal-based catalysts, including their oxides, hydroxides, nitrides, and phosphides, to reduce the cost of hydrogen production. The second major problem is the high energy consumption. The activation energy barriers for both the anode and cathode half-reactions are high; a theoretically required thermodynamic reaction requires an input energy of 237.2 KJ / mol, and the reaction kinetics are also very slow. Especially in the OER process, the complex four-electron transfer results in significant energy loss, and the produced oxygen has a low added value. Replacing the oxygen evolution reaction with a thermodynamically more favorable organic oxidation reaction is an effective way to solve these problems. Furthermore, this method reduces oxygen production and lowers the safety risks associated with mixing with hydrogen.

[0005] In organic oxidation reactions, biomass electrooxidation reaction (BEOR) has attracted much attention in recent years. Small-molecule biomass platform organic compounds such as pentahydroxymethylfurfural, glycerol, and benzyl alcohol are considered the most promising oxidation substrates. Among these organic compounds, benzoic acid, the oxidation product of benzyl alcohol, has wide applications in fragrances, preservatives, and pharmaceuticals. Furthermore, the electrooxidation process of benzyl alcohol is milder and more environmentally friendly than the industrial toluene oxidation process. Therefore, developing efficient non-precious metal-based catalysts for the benzyl alcohol electrooxidation reaction to enhance its application in electrocatalytic-assisted hydrogen evolution is of great significance. Summary of the Invention

[0006] In view of this, the technical problem to be solved by the present invention is to provide a catalytic material and its preparation method and its application in electrocatalytic selective oxidation of alcohols to assist hydrogen production. The catalytic material provided by the present invention has a high catalytic effect in electrocatalytic selective oxidation of alcohols to assist hydrogen production.

[0007] This invention provides a catalytic material, comprising:

[0008] Conductive carrier;

[0009] Transition metal phosphide nanosheets disposed on the conductive carrier; the transition metal phosphide is composed of Ni phosphide and a second transition metal phosphide, wherein the second transition metal phosphide is selected from at least two of Fe phosphide, Mo phosphide or Co phosphide;

[0010] Ni phosphide nanoparticles disposed on the transition metal phosphide nanosheets.

[0011] The catalytic material provided by this invention includes a conductive support, which serves to provide support and conduct electricity. In some embodiments of this invention, the conductive support is selected from nickel foam, carbon cloth, or copper foam.

[0012] The catalytic material provided by this invention further includes transition metal phosphide nanosheets disposed on the conductive support. Specifically, the transition metal phosphide nanosheets are vertically and alternately arranged on the conductive support to form a nanoarray structure. The transition metal phosphide is composed of Ni phosphide and a second transition metal phosphide, wherein the second transition metal phosphide is selected from at least two of Fe phosphide, Mo phosphide, or Co phosphide. Preferably, the second transition metal phosphide is selected from Fe phosphide and Mo phosphide; or, the second transition metal phosphide is selected from Fe phosphide and Co phosphide. The doping amount of the transition metal atoms in this invention is 20 wt% to 60 wt%. The thickness of the nanosheets in this invention is 15 nm to 20 nm. The catalytic material provided by this invention also includes Ni phosphide nanoparticles disposed on the transition metal phosphide nanosheets.

[0013] This invention also provides a method for preparing a catalytic material, comprising the following steps:

[0014] S1) A conductive support is subjected to a hydrothermal reaction in Ni salt, transition metal salt, urea and ammonium fluoride to obtain a precursor; the transition metal salt is selected from at least two of Fe salt, Mo salt or Co salt;

[0015] S2) In a protective atmosphere, the precursor obtained in step S1) is phosphated to obtain a catalytic material.

[0016] This invention first involves a hydrothermal reaction of a conductive support with Ni salt, a transition metal salt, urea, and ammonium fluoride to obtain a precursor. Specifically, Ni salt, transition metal salt, urea, ammonium fluoride, and water are mixed and dispersed to obtain a precursor solution; the conductive support is then placed in the precursor solution for a hydrothermal reaction, and the reacted conductive support is dried to obtain the precursor. The hydrothermal reaction temperature in this invention is 80℃~160℃; the hydrothermal reaction time is 4 h~10 h.

[0017] The Ni salt described in this invention is selected from one or more of Ni chloride or Ni nitrate. In some embodiments of this invention, the Ni salt is selected from one or more of nickel chloride or nickel nitrate. The transition metal salt described in this invention is selected from at least two of Fe salt, Mo salt, or Co salt; the transition metal salt is selected from one or more of transition metal chloride or transition metal nitrate. The molar ratio of Ni ions in the Ni salt, transition metal ions in the transition metal salt, urea, and ammonium fluoride in this invention is (0.1~5):(0.2~10):(1~10):(0.2~5), preferably (0.1~1.5):(0.2~1):(1~10):(0.2~2.5), more preferably (0.5~1.5):(0.2~1):(5~10):(1~2.5).

[0018] Preferably, the transition metal salt of the present invention comprises an Fe salt and a second transition metal salt; the second transition metal salt is selected from a Mo salt or a Co salt; the Fe salt is selected from one or more of Fe chloride or Fe nitrate; the Mo salt is selected from one or more of Mo inorganic sodium salt or Mo inorganic ammonium salt. In some embodiments of the present invention, the Fe salt is selected from one or more of ferric nitrate or ferric chloride; the Mo salt is selected from one or more of sodium molybdate or ammonium molybdate; and the Co salt is selected from one or more of cobalt nitrate or cobalt chloride. The molar ratio of Ni ions in the Ni salt, Fe ions in the Fe salt, transition metal ions in the second transition metal salt, urea, and ammonium fluoride in this invention is (0.1~5):(0.1~5):(0.1~5):(1~10):(0.2~5), preferably (0.1~1.5):(0.1~0.5):(0.1~0.5):(1~10):(0.2~2.5), and more preferably (0.5~1.5):(0.1~0.5):(0.1~0.5):(5~10):(1~2.5).

[0019] In this invention, after obtaining the precursor, the precursor is phosphated in a protective atmosphere to obtain a catalytic material. Specifically, in a protective atmosphere, a phosphorus source and the obtained precursor are phosphated by heat treatment to obtain the catalytic material described in this invention. The phosphated temperature in this invention is 300℃~500℃; the phosphated time is 2~4 h.

[0020] The present invention also provides the application of the catalytic material described in any of the above technical solutions or the catalytic material obtained by the preparation method described in any of the above technical solutions in the electrocatalytic selective oxidation of alcohols to assist hydrogen production.

[0021] Specifically, the present invention provides the application of the catalytic material described in any of the above technical solutions or the catalytic material obtained by the preparation method described in any of the above technical solutions as an anode catalyst in the selective oxidation of alcohols to assist hydrogen production.

[0022] More specifically, an aqueous solution of an alkali metal hydroxide of an alcohol is used as the electrolyte solution, and the electrolyte solution is electrolyzed through a cathode and an anode; the anode is the catalytic material described in any of the above-mentioned technical solutions or the catalytic material obtained by the preparation method described in any of the above-mentioned technical solutions. The alcohol in the electrolyte solution of this invention is selected from one or more of methanol, ethanol, benzyl alcohol, and glycerol; the concentration of the alcohol in the alcohol solution is greater than or equal to 10 mmol / L. The pH value of the electrolyte solution of this invention is 10-14. The voltage for selective oxidation of alcohols to assisted hydrogen production according to this invention is 1-2 V vs. RHE.

[0023] This invention provides a catalytic material, its preparation method, and its application in the selective oxidation of alcohols to assist hydrogen production via electrocatalysis. The invention synthesizes a highly efficient and stable bimetallic-doped nickel-based metal phosphide catalytic material via a simple hydrothermal and phosphating method. Phosphorus is doped onto amorphous nanosheets through annealing, forming Ni2P nanoparticles, which optimizes the electronic structure of the catalyst surface and further increases the number of active sites. This catalytic material exhibits a relatively rough, sheet-like structure. After phosphating, these sheet-like structures interweave to form a three-dimensional network of pores, enhancing the diffusion capacity of ions and electrons at the interface and effectively increasing the active surface area in the electrode-electrolyte contact region, thereby improving catalytic efficiency and kinetic performance. Applying the catalytic material of this invention to the electrocatalytic oxidation of alcohols to assist hydrogen evolution can help drive the electrocatalytic hydrogen evolution reaction with renewable energy, significantly reduce hydrogen production energy consumption, increase the hydrogen production rate, and simultaneously catalyze the directed oxidation of alcohols to obtain high-value-added chemicals such as acids. Attached Figure Description

[0024] Figure 1 The X-ray diffraction pattern of the molybdenum-doped nickel-based metal phosphide catalyst obtained in Example 1 of this invention;

[0025] Figure 2 This is a scanning electron microscope image of the molybdenum-doped nickel-based metal phosphide catalyst obtained in Example 1 of the present invention;

[0026] Figure 3 This is a transmission electron microscope (TEM) image of the molybdenum-doped nickel-based metal phosphide catalyst obtained in Example 1 of the present invention.

[0027] Figure 4 The XPS spectrum of the molybdenum-doped nickel-based metal phosphide catalyst obtained in Example 1 of this invention is shown below.

[0028] Figure 5 The polarization curve of the molybdenum-doped nickel-based metal phosphide catalyst obtained in Example 1 of this invention is shown at a scan rate of 5 mV / s.

[0029] Figure 6 The polarization curves of the catalysts obtained in Examples 1 and 2 and Comparative Examples 1 to 3 of this invention in 1 M KOH + 10 mM benzyl alcohol are shown.

[0030] Figure 7 The liquid chromatogram of the product obtained after the reaction catalyzed by the molybdenum-doped nickel-based metal phosphide catalyst obtained in Example 1 of this invention;

[0031] Figure 8 The conversion rate, selectivity, and Faraday efficiency of the molybdenum-doped nickel-based metal phosphide catalyst obtained in Example 1 of this invention are shown in the diagram.

[0032] Figure 9 This is a stability test diagram of the molybdenum-doped nickel-based metal phosphide catalyst obtained in Example 1 of the present invention. Detailed Implementation

[0033] This invention discloses a catalytic material, its preparation method, and its application in the selective oxidation of alcohols to assist hydrogen production via electrocatalysis. Those skilled in the art can refer to this document and appropriately modify the process parameters to achieve the desired result. It should be particularly noted that all similar substitutions and modifications are obvious to those skilled in the art and are considered to be included in this invention. The methods and applications of this invention have been described through preferred embodiments; those skilled in the art will clearly be able to modify or appropriately change and combine the methods and applications described herein without departing from the content, spirit, and scope of this invention to realize and apply the technology of this invention.

[0034] All reagents used in the following examples are commercially available; the nickel foam used is battery grade.

[0035] The present invention will be further described below with reference to the embodiments:

[0036] Example 1

[0037] (1) Sonicate 2 cm × 4 cm nickel foam in 3 M HCl solution for 15 min, rinse with excess anhydrous ethanol, and then sonicate in anhydrous ethanol for 15 min. After sonication, rinse repeatedly with excess deionized water and dry in a vacuum drying oven at 60℃ for 12 h to remove impurities from the surface of the nickel foam and obtain pretreated nickel foam.

[0038] (2) Weigh 1.5 mmol nickel nitrate hexahydrate, 0.5 mmol ferric nitrate nonahydrate, 0.5 mmol sodium molybdate dihydrate, 10 mmol urea and 2.5 mmol ammonium fluoride and dissolve them in 40 mL deionized water. Stir for 20 min to completely dissolve the dissolved substances and transfer them to a hydrothermal reactor lined with Teflon. Then, vertically place the pretreated nickel foam obtained in (1) into the reactor and heat it in a forced-air drying oven at 120 °C for 6 h. Remove the nickel foam from the hydrothermal reactor, wash it with distilled water and ethanol, and vacuum dry it at 60 °C for 12 h to obtain the hydrothermally treated precursor.

[0039] (3) The precursor material obtained in (2) was phosphated in a tube furnace using 0.8 g NaH2PO2·H2O powder as a phosphorus source. The furnace was kept at 300°C for 2 h under an argon atmosphere. After cooling to room temperature, the material was taken out and washed with ethanol. Then it was placed in a vacuum drying oven and dried under vacuum at 60°C to obtain a molybdenum-doped nickel-based metal phosphide catalyst, denoted as Mo-NiFeP / NF.

[0040] Example 2

[0041] Based on Example 1, sodium molybdate dihydrate was replaced with cobalt nitrate hexahydrate, while other parameters remained unchanged, resulting in a cobalt-doped nickel-based metal phosphide catalyst, denoted as Co-NiFeP / NF.

[0042] Comparative Example 1

[0043] Based on Example 1, without adding sodium molybdate dihydrate, and with everything else unchanged, a molybdenum-free nickel-based metal phosphide catalyst was obtained, denoted as NiFeP / NF.

[0044] Comparative Example 2

[0045] Based on Example 1, sodium molybdate dihydrate was replaced with aluminum nitrate nonahydrate, while other parameters remained unchanged, resulting in an aluminum-doped nickel-based metal phosphide catalyst, denoted as Al-NiFeP / NF.

[0046] Comparative Example 3

[0047] Based on Example 1, sodium molybdate dihydrate was replaced with manganese chloride tetrahydrate, while other parameters remained unchanged, resulting in a manganese-doped nickel-based metal phosphide catalyst, denoted as Mn-NiFeP / NF.

[0048] Crystal structure analysis of the sample:

[0049] XRD patterns of the molybdenum-doped nickel-based metal phosphide catalyst and control material obtained in Example 1 were scanned using an EMPYREAN X-ray powder diffractometer. The specific operation procedure and equipment parameters are as follows: The prepared molybdenum-doped nickel-based metal phosphide catalyst material was cut into a small piece, adhered to the test tray with tape, and placed on the XRD sample stage for XRD pattern scanning. Because the intensity of the nickel foam diffraction peaks was too high and would mask the diffraction peaks of similar samples, the catalyst was ultrasonically dissolved in anhydrous ethanol, and the solution was dropped onto the test tray for testing. The scanning parameters were as follows: scanning range 5°~90°, scanning speed 5° / min. Figure 1 As shown, Figure 1 This is the X-ray diffraction pattern of the molybdenum-doped nickel-based metal phosphide catalyst obtained in Example 1 of this invention. Figure 1 It can be seen that Mo-NiFeP / NF has Ni2P (PDF#74-1385) diffraction peaks on the (111) crystal plane (40.7°), (201) crystal plane (44.6°), (210) crystal plane (47.4°), (300) crystal plane (54.2°), (211) crystal plane (55.0°) and (400) crystal plane (74.8°), but the peak intensity is weak. This is due to the low crystallinity or the presence of an amorphous morphology.

[0050] Characterization of sample morphology:

[0051] The sample was prepared using a Zeiss GeminiSEM300 field emission scanning electron microscope (SEM) from Germany. The preparation method was as follows: The molybdenum-doped nickel-based metal phosphide catalyst material obtained in Example 1 was adhered to conductive adhesive on a test tray, placed on the test stage, and its morphology was observed after parameter adjustment. The resulting SEM image is shown below. Figure 2 As shown, Figure 2 This is a scanning electron microscope (SEM) image of the molybdenum-doped nickel-based metal phosphide catalyst obtained in Example 1 of this invention. Figure 2 As can be seen, the Mo-doped NiFeP layer exhibits a relatively rough lamellar structure. These lamellar structures are interconnected after phosphating, forming a three-dimensional network of pores. This unique pore system not only maintains the original porosity but also further enhances the diffusion capacity of ions and electrons at the interface, effectively increasing the active surface area in the electrode-electrolyte contact region, thereby improving catalytic efficiency and kinetic performance.

[0052] The sample preparation method was as follows, using a Tecnai F20 field emission transmission electron microscope: the catalyst grown in situ in nickel foam was ultrasonicated in anhydrous ethanol, and the solution was then dropped onto a copper sheet for testing. The transmission electron microscope image is shown below. Figure 3 As shown, Figure 3 This is a transmission electron microscope (TEM) image of the molybdenum-doped nickel-based metal phosphide catalyst obtained in Example 1 of the present invention. Figure 3 The results show that Mo-NiFeP / NF retains its lamellar structure after phosphating, and the formation of Ni2P nanoparticles on the surface can be clearly seen, which is consistent with the morphology observed in the SEM and HRTEM images.

[0053] X-ray photoelectron spectroscopy (XPS) of the sample:

[0054] XPS spectra of the samples were measured using Thermo Fisher Scientific's Nexsa instrument, with a base vacuum of 3 × 10⁻⁶. -9 mbar, power 300 W. During data processing, the C 1s peak of contaminating carbon is used to perform energy correction on XPS. Then, by comparing with standard spectra and using XPSPEAK software to perform peak fitting on the full spectrum of XPS and high-resolution spectra of major metal elements, the valence states and bonding relationships between elements are preliminarily determined, resulting in the XPS energy spectrum of the molybdenum-doped nickel-based metal phosphide catalyst, such as... Figure 4 As shown, Figure 4 This is the XPS spectrum of the molybdenum-doped nickel-based metal phosphide catalyst obtained in Example 1 of this invention. Figure 4It can be seen that the surface of the molybdenum-doped nickel-based metal phosphide sample is mainly composed of Ni, Fe, Mo, P, O and C elements. Meanwhile, the shift of the position of each peak indicates that the doping of P element can effectively regulate the chemical environment of the metal site and may have a positive impact on the catalytic ability. The doping of Mo is beneficial to accelerate electron transfer and optimize proton adsorption.

[0055] OER and BOR polarization curves of electrode materials:

[0056] The molybdenum-doped nickel-based metal phosphide catalyst obtained in Example 1 was used as the working electrode. An Ag / AgCl electrode and a Pt sheet were used as the reference and counter electrodes, respectively. 1 M potassium hydroxide solution and 10 mM benzyl alcohol (BA) were used as the electrolyte and electrolyte, respectively, with comparisons made to a solution without 10 mM BA. The tests were performed on a Shanghai Chenhua CHI760E electrochemical workstation at a scan rate of 5 mV / s. Figure 5 As shown, Figure 5 The graph shows the polarization of the molybdenum-doped nickel-based metal phosphide catalyst obtained in Example 1 of this invention at a scan rate of 5 mV / s. The Mo-NiFeP / NF catalyst was reacted in a 1 M potassium hydroxide solution containing benzyl alcohol at a scan rate of 10 mA cm⁻¹. -2 and 100 mA cm -2 The potentials at the current densities were 1.355 V vs. RHE and 1.381 V vs. RHE, respectively, which were 31 mV (10 mA cm⁻¹) lower than the OER potential in potassium hydroxide solution without benzyl alcohol. -2 ) and 55 mV (100 mA cm -2 ).

[0057] BOR polarization curves of electrode materials and control samples:

[0058] The catalysts obtained in Examples 1 and 2 and Comparative Examples 1-3 were used as working electrodes, respectively. An Ag / AgCl electrode and a Pt sheet were used as the reference and counter electrodes, respectively. 1 M potassium hydroxide solution and 10 mM benzyl alcohol (BA) were used as the electrolyte and electrolyte solution, respectively. Electrochemical tests were conducted at a scan rate of 5 mV / s using a Shanghai Chenhua CHI760E electrochemical workstation. Figure 6 As shown, Figure 6 The graphs show the polarization curves of the catalysts obtained in Examples 1 and 2 and Comparative Examples 1-3 of this invention in 1 M KOH + 10 mM benzyl alcohol. Figure 6 It can be seen that Mo-NiFeP / NF at 10 mA cm⁻¹ -2 and 100 mA cm -2The potentials at the current densities were 1.361 V vs. RHE and 1.406 V vs. RHE, respectively; Co-NiFeP / NF at 10 mA cm⁻¹ -2 and 100 mA cm -2 The potentials at the current densities are 1.375 V vs. RHE and 1.425 V vs. RHE, respectively, both of which outperform NiFeP / NF (1.394 V vs. RHE (10 mA cm⁻¹)). -2 ), 1.535 Vvs.RHE (100 mA cm -2 ))), Al-NiFeP / NF (1.462 Vvs.RHE (10mA cm -2 ), 1.619 Vvs.RHE (100 mA cm -2 ))) and Mn-NiFeP / NF (1.369 V vs. RHE (10 mA cm) -2 ), 1.576 Vvs.RHE (100 mA cm -2 ))).

[0059] Liquid chromatogram of electrode material:

[0060] The products after BOR testing were qualitatively and quantitatively analyzed using an Agilent 1260 semi-preparative liquid chromatography system. The results are as follows: Figure 7 As shown, Figure 7 This is a liquid chromatogram of the product obtained after the reaction catalyzed by the molybdenum-doped nickel-based metal phosphide catalyst obtained in Example 1 of this invention. The conversion rate of benzyl alcohol and the yield of benzoic acid continuously increase with time. The intermediate product benzaldehyde is initially detected and reaches its highest value at 1000 s, but it does not accumulate during the oxidation process, indicating that benzaldehyde is rapidly oxidized to benzoic acid. At a reaction time of 5000 s, the reactants are almost completely converted, with a conversion rate of 99% for benzyl alcohol and a selectivity for benzoic acid close to 98.5%.

[0061] Conversion rate, selectivity, and Faraday efficiency of electrode materials:

[0062] Electrochemical performance testing and data acquisition were conducted using a Nafion 117 membrane-separated two-compartment H-type electrolytic cell. An Ag / AgCl (3 M KCl) electrode was used as the reference electrode, and a platinum sheet was selected as the counter electrode. The molybdenum-doped nickel-based metal phosphide catalyst obtained in Example 1 was used as the working electrode. A 1 M potassium hydroxide solution containing 10 mM benzyl alcohol was used as the electrolyte. Chronoamperometry was performed six times at 0.4 V vs. Ag / AgCl potential to obtain the conversion rate, selectivity, and Faraday efficiency plots of the molybdenum-doped nickel-based metal phosphide catalyst. Figure 8 As shown, Figure 8 The graphs show the conversion rate, selectivity, and Faraday efficiency of the molybdenum-doped nickel-based metal phosphide catalyst obtained in Example 1 of this invention. Figure 8 It can be seen that after six consecutive tests, the catalyst still maintains a high conversion rate of benzyl alcohol and a high selectivity for benzoic acid.

[0063] Stability of electrode materials:

[0064] The stability of benzyl alcohol electro-oxidation was evaluated through repeated iterative tests. The experiment was terminated after 5000 s of constant current testing, and was repeated 6 times. The long-term stability of the molybdenum-doped nickel-based metal phosphide sample was verified in a 1 M potassium hydroxide solution containing 10 mM benzyl alcohol. The stability test results are shown in the figure below. Figure 9 As shown, Figure 9 This is a stability test diagram of the molybdenum-doped nickel-based metal phosphide catalyst obtained in Example 1 of the present invention. Figure 9 It can be seen that after 6 cycles, the LSV curve of this electrode material does not change much, indicating that it has good stability and good electro-oxidation ability of benzyl alcohol.

[0065] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. The application of a catalytic material in the electrocatalytic selective oxidation of alcohols to assist hydrogen production, characterized in that, The catalytic material includes: Conductive carrier; Transition metal phosphide nanosheets disposed on the conductive carrier; the transition metal phosphide is composed of Ni phosphide and a second transition metal phosphide, wherein the second transition metal phosphide is selected from Fe phosphide and Mo phosphide; or, the second transition metal phosphide is selected from Fe phosphide and Co phosphide; Ni phosphide nanoparticles disposed on the transition metal phosphide nanosheets.

2. The application according to claim 1, characterized in that, The doping amount of the transition metal atoms is 20 wt% to 60 wt%.

3. The application according to claim 1, characterized in that, The thickness of the nanosheet is 15 nm to 20 nm.

4. The application of a catalytic material prepared by a method for electrocatalytic selective oxidation of alcohols to assisted hydrogen production, characterized in that, The preparation method of the catalytic material includes the following steps: S1) A conductive support is subjected to a hydrothermal reaction in Ni salt, transition metal salt, urea and ammonium fluoride to obtain a precursor; the transition metal salt includes Fe salt and a second transition metal salt; the second transition metal salt is selected from Mo salt or Co salt. S2) In a protective atmosphere, the precursor obtained in step S1) is phosphated to obtain a catalytic material; The catalytic material includes: Conductive carrier; Transition metal phosphide nanosheets disposed on the conductive carrier; the transition metal phosphide is composed of Ni phosphide and a second transition metal phosphide, wherein the second transition metal phosphide is selected from Fe phosphide and Mo phosphide; or, the second transition metal phosphide is selected from Fe phosphide and Co phosphide; Ni phosphide nanoparticles disposed on the transition metal phosphide nanosheets.

5. The application according to claim 4, characterized in that, In step S1), the molar ratio of Ni ions in the Ni salt, Fe ions in the Fe salt, transition metal ions in the second transition metal salt, urea, and ammonium fluoride is (0.1~5):(0.1~5):(0.1~5):(1~10):(0.2~5).

6. The application according to claim 4, characterized in that, In step S1), the temperature of the hydrothermal reaction is 80℃~160℃; the time of the hydrothermal reaction is 4 h~10 h.

7. The application according to claim 4, characterized in that, In step S2), the phosphating temperature is 300℃~500℃; the phosphating time is 2~4 h.

Images