Wood derived carbon supported metal oxide-alloy heterojunction hydrogen production catalyst

Abstract

The invention discloses a wood derived carbon supported metal oxide-alloy heterojunction hydrogen production catalyst. The wood derived carbon supported metal oxide-alloy heterojunction hydrogen production catalyst is formed by a metal oxide-alloy heterojunction and is loaded on a wood derived carbon substrate; the catalyst comprises a metal element and a non-metal element with catalytic activity. The nickel-iron-molybdenum heterojunction water electrolysis hydrogen production catalyst has the advantages that the preparation process is simple, and the used metal is transition metal, so that the cost is low; the Ni3Fe / MoO2 heterojunction is loaded on the wood derived carbon substrate and has good hydrogen evolution reaction (HER) electrochemical catalytic activity in an alkaline solution, the overpotential required for reaching-10 mA / cm < 2 > is smaller than or equal to 150 mV, the overpotential required for reaching 300 mA / cm < 2 > is smaller than or equal to 500 mV, and a technical foundation is laid for reducing the cost of industrial hydrogen production through water electrolysis.

Description

Technical Field

[0001] The invention relates to the technical field of catalysts for hydrogen production by electrolysis of water, and in particular to a wood-derived carbon-supported metal oxide-alloy heterojunction hydrogen production catalyst. Background Art

[0002] Hydrogen energy is a renewable clean energy with broad development prospects, which is conducive to solving the problem of growing global energy demand. As an ideal method for hydrogen production, water electrolysis has attracted widespread attention in recent years. In actual situations, the hydrogen evolution reaction (HER) at the cathode and the oxygen evolution reaction (OER) at the anode in the water electrolysis process have high overpotentials, which limits the further application of water electrolysis to produce hydrogen, resulting in slow kinetics. Therefore, it is necessary to develop efficient water electrolysis catalysts to accelerate the reaction process. Precious metals (Pt, Ru) can effectively accelerate the process of water electrolysis to produce hydrogen, but their expensive prices and low reserves limit their industrial applications. Transition metals (Ni, Mo, Fe, etc.) have the advantages of low price and large reserves, and have certain water electrolysis hydrogen production performance, and have great development prospects.

[0003] In addition, the commonly used substrates in electrodes are mainly metal foam or carbon cloth, and their complex preparation process and high cost restrict the application of electrodes. As the most abundant biopolymer on earth, wood has a unique three-dimensional porous structure, a variety of functional groups that can coordinate with metal ions, and has excellent conductivity and high rate performance after high-temperature annealing, as well as ultra-high porosity and specific surface area. The combination of catalytic metal species and highly conductive carbon matrix can effectively prevent the agglomeration of metal nanoparticles, avoid corrosion by strong acids and strong bases, and improve the activity and stability of metal catalysts.

[0004] Therefore, the development of inexpensive and efficient transition metal-based wood-derived carbon electrodes is the key to solving the above problems. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides a wood-derived carbon-supported metal oxide-alloy heterojunction hydrogen production catalyst, aiming to obtain a metal oxide-alloy heterojunction water electrolysis hydrogen production catalyst supported on a wood-derived carbon substrate with simple process, low cost and good catalytic performance.

[0006] To achieve the above purpose, the technical solution provided by the present invention is as follows:

[0007] A wood-derived carbon-supported metal oxide-alloy heterojunction hydrogen production catalyst, having a metal oxide-alloy heterojunction and supported on a wood-derived carbon substrate; the catalyst comprises a catalytically active metal element and a non-metal element, wherein the catalytically active metal element is at least one of Ni, Fe, Mo, V, Co, W, and Cr; the non-metal element is C and / or O; wherein the active group is dispersed in the catalyst.

[0008] Furthermore, the diffraction peaks in the XRD spectrum of the catalyst belong to wood-derived carbon, metal alloys and metal oxides.

[0009] The method for preparing the wood-derived carbon-supported metal oxide-alloy heterojunction hydrogen production catalyst as described above comprises the following steps:

[0010] (1) heating wood chips in distilled water at 80° C. for 10 hours, adding a mixed solution composed of deionized water, acetic acid and sodium chlorite for the first time, adding the wood chips heated for 10 hours into the mixed solution, and stirring at 80° C. at 60-70 rpm for 1 hour, adding the same mass of acetic acid and sodium chlorite as the first time for the second time, and continuing to stir at 80° C. at 60-70 rpm, and finally taking out the wood chips and air-drying them to obtain pretreated wood chips; the mass ratio of the added wood chips to the deionized water, acetic acid and sodium chlorite added for the first time is 1-5:100-300:1-10:1-10;

[0011] (2) dissolving metal salt A in a solvent to obtain a metal salt A solution, placing the wood chips pretreated in step (1) into the obtained metal salt A solution, and vacuum impregnating the wood chips for 8 hours. After the impregnation is completed, the wood chips are taken out, washed, and dried to obtain impregnated wood chips; the metal salt A is one of an iron salt, a nickel salt, or a cobalt salt;

[0012] (3) placing the wood chips obtained after impregnation in step (2) in a tubular furnace and introducing argon gas at 800-1200° C. for high temperature calcination for 1-6 hours to obtain sample B;

[0013] (4) dissolving metal salt C in a solvent to obtain a metal salt C solution, placing the metal salt C solution and the sample B in step (2) in a reactor, stirring, and then performing a solvent thermal reaction. After the reaction is completed, the mixture is cooled to room temperature, and the obtained material in the reactor is taken out for cleaning and drying to obtain a preliminary sample; the solvent thermal reaction is performed at 100-200° C. for 2-48 hours; the metal salt C is obtained by mixing metal salt D and metal salt E in any proportion, wherein metal salt D is one or two of iron salt, nickel salt, and cobalt salt, which are different from the metal salt in the metal salt A solution; and metal salt E is one of molybdenum salt, vanadium salt, chromium salt, and tungsten salt;

[0014] (5) placing the preliminary sample obtained in step (4) in a tubular furnace and introducing a mixture of hydrogen and argon into the furnace for high temperature calcination at 200-900° C. for 1-6 hours to obtain a wood-derived carbon-supported metal oxide-alloy heterojunction hydrogen production catalyst.

[0015] Preferably, the mass ratio of the wood chips added in step (1) to the deionized water, acetic acid and sodium chlorite added for the first time is 3-4:130-250:1-5:1-4; the wood chips in step (1) are one of natural woods such as pine, poplar, balsa, birch, fir, beech or eucalyptus.

[0016] Preferably, the nickel salt described in step (2) is nickel chloride, nickel acetylacetonate, nickel acetate, nickel bromide, nickel iodide, nickel sulfate, nickel nitrate, or nickel ammonium sulfate; the cobalt salt described in step (2) is one of cobalt chloride, cobalt sulfate, cobalt nitrate, cobalt carbonate, cobalt acetate, cobalt oxalate, cobalt phosphate, cobalt bromide, cobalt iodide, and cobalt sulfide; the iron salt described in step (2) is one of ferric chloride, ferric sulfate, ferric nitrate, ferric carbonate, ferric oxalate, ferric phosphate, ferric bromide, ferric iodide, ferrous sulfate, ferrous sulfate, ferrous nitrate, and ferrous chloride; the solvents described in steps (2) and (4) are all water, methanol, ethanol, ethylene glycol, isopropanol, n-butanol, n-hexane, cyclohexane, ether, or petroleum ether.

[0017] Preferably, the concentration of the metal salt A solution in step (2) is 0.001-5 mmol / mL; in step (3), argon gas is introduced to carry out high-temperature calcination at 800-900° C., and the insulation time is 2-6 hours.

[0018] Preferably, during the stirring process described in step (4), the stirring speed is 60-70 rpm, the temperature is 80° C., and the stirring time is 15 minutes; the solvent thermal reaction is carried out at 120-180° C. for 8-20 hours; and the concentrations of the metal salt D and the metal salt E in step (4) are each 0.001-10 mmol / mL.

[0019] Preferably, the nickel salt described in step (4) is nickel chloride, nickel acetylacetonate, nickel acetate, nickel bromide, nickel iodide, nickel sulfate, nickel nitrate, or nickel ammonium sulfate; the cobalt salt described in step (4) is one of cobalt chloride, cobalt sulfate, cobalt nitrate, cobalt carbonate, cobalt acetate, cobalt oxalate, cobalt phosphate, cobalt bromide, cobalt iodide, and cobalt sulfide; the iron salt described in step (4) is one of ferric chloride, ferric sulfate, ferric nitrate, ferric carbonate, ferric oxalate, ferric phosphate, ferric bromide, ferric iodide, ferrous sulfate, ferrous sulfate, ferrous nitrate, and ferrous chloride; the molybdenum salt described in step (4) is one of sodium molybdate, ammonium molybdate, The invention relates to one of calcium molybdate, potassium molybdate, ammonium hydrogen molybdate, ammonium phosphomolybdate and molybdenum pentachloride; the type of vanadium salt described in step (4) is one of vanadium sulfate, vanadium chloride, vanadium nitrate, sodium metavanadate, potassium metavanadate, vanadium pentoxide, ammonium vanadate, vanadium trioxide and vanadyl sulfate; the type of chromium salt described in step (4) is chromium nitrate, potassium chromate, potassium dichromate, chromium acetate and ammonium chromate; the tungsten salt described in step (4) is one of sodium tungstate, calcium tungstate and ammonium tungstate; the solvent described in step (4) is water, methanol, ethanol, ethylene glycol, isopropanol, n-butanol, n-hexane, cyclohexane, ether and petroleum ether.

[0020] Preferably, the high temperature calcination in step (5) is carried out at a heating rate of 1-20°C / min, 400-600°C, and a holding time of 3-6 hours; the volume fraction of hydrogen in the mixed gas is 1%-30%.

[0021] As mentioned above, the application of wood-derived carbon-supported metal oxide-alloy heterojunction hydrogen production catalysts in hydrogen evolution reaction and oxygen evolution reaction.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] The invention adopts wood-derived carbon material as a carrier, and obtains a wood-derived carbon-supported metal oxide-alloy heterojunction hydrogen production catalyst through vacuum impregnation, solvent thermal reaction and high-temperature calcination with metal salt; the preparation process of the invention is simple, and the cost of using metal as transition metal is low. The prepared nickel-iron-molybdenum heterojunction water electrolysis hydrogen production catalyst has the following characteristics: the Ni3Fe / MoO2 heterojunction is loaded on the wood-derived carbon substrate, and has good electrochemical catalytic activity of hydrogen evolution reaction (HER) in alkaline solution, reaching -10mA / cm 2 The required overpotential is less than or equal to 150mV, and the hydrogen evolution reaction (OER) reaches 300mA / cm 2 The required overpotential is less than or equal to 500mV, which lays a technical foundation for reducing the cost of industrial hydrogen production by water electrolysis. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1(a) is a transmission electron microscopy (TEM) image of the wood-derived carbon-supported metal oxide-alloy heterojunction hydrogen production catalyst prepared in Example 2 of the present invention; Figure 1 (b) is a high-resolution transmission electron microscopy (HRTEM) image of the wood-derived carbon-supported metal oxide-alloy heterojunction hydrogen production catalyst prepared in Example 2 of the present invention.

[0025] Figure 2 Field emission scanning electron microscope (SEM) images of different sizes of the wood-derived carbon-supported metal oxide-alloy heterojunction hydrogen production catalyst prepared in Example 2 of the present invention.

[0026] Figure 3 (a) is an annular dark field scanning transmission electron microscopy (HAADF-STEM) of the wood-derived carbon-supported metal oxide-alloy heterojunction hydrogen production catalyst prepared in Example 2 of the present invention; Figure 3 (b) is the energy spectrum (EDS) of the wood-derived carbon-supported metal oxide-alloy heterojunction hydrogen production catalyst prepared in Example 2 of the present invention obtained by X-ray energy dispersive spectrometry.

[0027] Figure 4 This is the X-ray diffraction pattern (XRD) of the wood-derived carbon-supported metal oxide-alloy heterojunction hydrogen production catalyst prepared in Example 2 of the present invention; wherein Ni3Fe / MoO2 / CW is the XRD data of the wood-derived carbon-supported metal oxide-alloy heterojunction hydrogen production catalyst prepared in Example 2 of the present invention, and MoO2, C, and Ni3Fe are standard cards.

[0028] Figure 5 A polarization curve diagram of hydrogen evolution reaction of the catalyst of the present invention in 1.0 mol / L potassium hydroxide solution of a wood-derived carbon-supported metal oxide-alloy heterojunction hydrogen production catalyst;

[0029] Figure 6 The Tafel slope diagram of hydrogen evolution of the catalyst of the present invention in 1.0 mol / L potassium hydroxide solution of the metal oxide-alloy heterojunction hydrogen production catalyst supported by wood-derived carbon;

[0030] Figure 7 A polarization curve diagram of the oxygen evolution reaction of the metal oxide-alloy heterojunction hydrogen production catalyst supported by wood-derived carbon in a 1.0 mol / L potassium hydroxide solution;

[0031] Figure 8 The Tafel slope diagram of oxygen evolution of the catalyst of the present invention in 1.0 mol / L potassium hydroxide solution of the metal oxide-alloy heterojunction hydrogen production catalyst supported by wood-derived carbon;

[0032] in, Figure 5 , Figure 6 , Figure 7 and Figure 8 The Ni3Fe / MoO2 / CW line in the middle is the data of the catalyst prepared in Example 2, the Ni3Fe / CW line is the data of the catalyst prepared in Comparative Example 1, and the MoO2 / CW line is the data of the catalyst prepared in Comparative Example 2. DETAILED DESCRIPTION

[0033] The specific implementation is described in detail below in conjunction with the accompanying drawings, but it should be understood that the protection scope of the present invention is not limited by the specific implementation. The raw materials and reagents used in the examples are all commercially available unless otherwise specified.

[0034] In the present invention, the XRD test method is to test the catalyst by using a Minflex600 X-ray diffractometer produced by Rigaku Corporation of Japan to determine the material composition of the catalyst. The conditions are as follows: the X-ray tube is operated at 40 kV and 40 mA, and the scanning speed is 10°·min -1 , the 2θ scanning range was 5-90°.

[0035] Example 1

[0036] A method for preparing a wood-derived carbon-supported metal oxide-alloy heterojunction hydrogen production catalyst, the operating steps are as follows:

[0037] (1) According to the mass ratio of wood chips, deionized water, acetic acid, and sodium chlorite being 4:130:2:1, 4 g of poplar wood chips, 130 g of deionized water, 2 g of acetic acid, and 1 g of sodium chlorite were weighed, and the poplar wood chips were heated in distilled water at 80° C. for 10 hours, and the deionized water, acetic acid, and sodium chlorite weighed above were mixed to obtain a mixed solution (this was the first time that acetic acid and chlorite were added), and the poplar wood chips heated for 10 hours were put into the mixed solution and stirred at 80° C. at 63 rpm for 1 hour, and then the same mass of acetic acid (newly weighed 2 g) and sodium chlorite (newly weighed 1 g) as the first time were added again and continued to be stirred at 80° C. at 60 rpm, and finally the wood chips were taken out and air-dried to obtain pretreated wood chips;

[0038] (2) dissolving 1.2 g of nickel chloride in 40 mL of deionized water to obtain a metal salt A solution with a concentration of 0.23 mmol / mL, placing the wood chips pretreated in step (1) into the obtained metal salt A solution, and vacuum impregnating for 8 hours. After the impregnation is completed, the wood chips are taken out, washed, and dried to obtain impregnated wood chips;

[0039] (3) placing the wood chips obtained after the impregnation in step (2) in a tube furnace, introducing argon gas at a rate of 25 mL / min, and heating the temperature to 900°C at a rate of 10°C / min for high temperature calcination for 3 hours to obtain sample B;

[0040] (4) 300 mg of ferric chloride and 200 mg of vanadium chloride were dissolved in 40 mL of ethylene glycol to obtain a metal salt C solution with a concentration of 0.0078 mmol / mL. The metal salt C solution and the sample B in step (2) were placed in a reactor and stirred at 80° C. and 64 rpm for 15 minutes, followed by a solvothermal reaction. The reaction temperature was 120° C. and the reaction time was 30 hours. After the reaction was completed, the reaction was cooled to room temperature, and the material obtained in the reactor was taken out for cleaning and drying to obtain a preliminary sample;

[0041] (5) The preliminary sample obtained in step (4) is placed in a tubular furnace, and a mixed gas of hydrogen and argon (the volume fraction of hydrogen in the mixed gas is 10%) is introduced at a rate of 30 mL / min, and the temperature is raised to 600°C for high-temperature calcination at a rate of 10°C / min. The temperature is kept at a temperature of 3 hours to obtain a wood-derived carbon-supported metal oxide-alloy heterojunction hydrogen production catalyst.

[0042] Example 2

[0043] A method for preparing a wood-derived carbon-supported metal oxide-alloy heterojunction hydrogen production catalyst, the operating steps are as follows:

[0044] (1) According to the mass ratio of wood chips, deionized water, acetic acid, and sodium chlorite being 4:130:1:1, 4 g of poplar wood chips, 130 g of deionized water, 1 g of acetic acid, and 1 g of sodium chlorite were weighed, and the poplar wood chips were heated in distilled water at 80° C. for 10 hours, and the deionized water, acetic acid, and sodium chlorite weighed above were mixed to obtain a mixed solution (this was the first time that acetic acid and chlorite were added), and the poplar wood chips heated for 10 hours were put into the mixed solution and stirred at 80° C. at 65 rpm for 1 hour, and then the same mass of acetic acid (newly weighed 2 g) and sodium chlorite (newly weighed 1 g) as the first time were added again and continued to be stirred at 80° C. at 70 rpm, and finally the wood chips were taken out and air-dried to obtain pretreated wood chips;

[0045] (2) dissolving 2 g of nickel nitrate in 50 mL of deionized water to obtain a metal salt A solution with a concentration of 0.21 mmol / mL, placing the wood chips pretreated in step (1) into the obtained metal salt A solution, and vacuum impregnating for 8 hours. After the impregnation is completed, the wood chips are taken out, washed, and dried to obtain impregnated wood chips;

[0046] (3) placing the wood chips obtained after impregnation in step (2) in a tube furnace, introducing argon gas at a rate of 40 mL / min, and heating the temperature to 800°C at a rate of 5°C / min for high temperature calcination, and keeping the temperature for 2 hours to obtain sample B;

[0047] (4) 300 mg of ferric nitrate and 400 mg of sodium molybdate were dissolved in 30 mL of deionized water to obtain a metal salt C solution with a concentration of 0.10 mmol / mL. The metal salt C solution and the sample B in step (2) were placed in a reactor and stirred at 80° C. and 65 rpm for 15 minutes, and then a solvent thermal reaction was carried out. The reaction temperature was 180° C. and the reaction time was 8 hours. After the reaction was completed, the mixture was cooled to room temperature, and the material obtained in the reactor was taken out for washing and drying to obtain a preliminary sample;

[0048] (5) The preliminary sample obtained in step (4) is placed in a tubular furnace, and a mixed gas of hydrogen and argon (the volume fraction of hydrogen in the mixed gas is 5%) is introduced at a rate of 40 mL / min, and the temperature is raised to 400°C for high-temperature calcination at a rate of 5°C / min. The temperature is kept at a high temperature for 3 hours to obtain a wood-derived carbon-supported metal oxide-alloy heterojunction hydrogen production catalyst (Ni3Fe / MoO2 / CW).

[0049] Example 3

[0050] A method for preparing a wood-derived carbon-supported metal oxide-alloy heterojunction hydrogen production catalyst, the operating steps are as follows:

[0051] (1) According to the mass ratio of wood chips, deionized water, acetic acid, and sodium chlorite being 3:250:5:4, 3 g of balsa wood chips, 250 g of deionized water, 5 g of acetic acid, and 4 g of sodium chlorite were weighed, and the balsa wood chips were heated in distilled water at 80° C. for 10 hours, and the deionized water, acetic acid, and sodium chlorite weighed above were mixed to obtain a mixed solution (this was the first time that acetic acid and chlorite were added), and the poplar wood chips heated for 10 hours were put into the mixed solution and stirred at 80° C. at 68 rpm for 1 hour, and then the same mass of acetic acid (newly weighed 5 g) and sodium chlorite (newly weighed 4 g) as the first time were added again and continued to be stirred at 80° C. at 70 rpm, and finally the wood chips were taken out and air-dried to obtain pretreated wood chips;

[0052] (2) dissolving 1.9 g of cobalt acetate in 50 mL of methanol to obtain a metal salt A solution with a concentration of 0.21 mmol / mL, placing the wood chips pretreated in step (1) into the obtained metal salt A solution, and vacuum impregnating for 8 hours. After the impregnation is completed, the wood chips are taken out, washed, and dried to obtain impregnated wood chips;

[0053] (3) placing the wood chips obtained after impregnation in step (2) in a tube furnace, introducing argon gas at 45 mL / min, maintaining a heating rate of 12°C / min and raising the temperature to 900°C for high-temperature calcination, and keeping the temperature for 3 hours to obtain sample B;

[0054] (4) 320 mg of ferric nitrate and 300 mg of ammonium tungstate were dissolved in 30 mL of deionized water to obtain a metal salt C solution with a concentration of 0.07 mmol / mL. The metal salt C solution and the sample B in step (2) were placed in a reactor and stirred at 80° C. and 68 rpm for 15 minutes, and then a solvent thermal reaction was carried out. The reaction temperature was 130° C. and the reaction time was 18 hours. After the reaction was completed, the reaction was cooled to room temperature, and the material obtained in the reactor was taken out for washing and drying to obtain a preliminary sample;

[0055] (5) The preliminary sample obtained in step (4) is placed in a tubular furnace, and a mixed gas of hydrogen and argon (the volume fraction of hydrogen in the mixed gas is 8%) is introduced at a rate of 30 mL / min, and the heating rate is maintained at 12°C / min, and the temperature is raised to 500°C for high-temperature calcination, and the heat preservation time is 6 hours to obtain a wood-derived carbon-supported metal oxide-alloy heterojunction hydrogen production catalyst.

[0056] Example 4

[0057] A method for preparing a wood-derived carbon-supported metal oxide-alloy heterojunction hydrogen production catalyst, the operating steps are as follows:

[0058] (1) According to the mass ratio of wood chips, deionized water, acetic acid, and sodium chlorite being 3:150:1.2:1.5, 3 g of birch wood chips, 150 g of deionized water, 1.2 g of acetic acid, and 1.5 g of sodium chlorite were weighed, and the birch wood chips were heated in distilled water at 80° C. for 10 hours, and the deionized water, acetic acid, and sodium chlorite weighed above were mixed to obtain a mixed solution (this was the first time that acetic acid and chlorite were added), and the poplar wood chips heated for 10 hours were put into the mixed solution and stirred at 80° C. at 70 rpm for 1 hour, and then the same mass of acetic acid (newly weighed 1.2 g) and sodium chlorite (newly weighed 1.5 g) as the first time were added again, and stirring continued at 80° C. at 61 rpm, and finally the wood chips were taken out and air-dried to obtain pretreated wood chips;

[0059] (2) dissolving 1.9 g of cobalt acetate in 40 mL of petroleum ether to obtain a metal salt A solution with a concentration of 0.26 mmol / mL, placing the wood chips pretreated in step (1) into the obtained metal salt A solution, and vacuum impregnating for 8 hours. After the impregnation is completed, the wood chips are taken out, washed, and dried to obtain impregnated wood chips;

[0060] (3) placing the wood chips obtained after impregnation in step (2) in a tube furnace, introducing argon gas at a rate of 55 mL / min, and heating the temperature to 800°C at a rate of 12°C / min for high temperature calcination for 6 hours to obtain sample B;

[0061] (4) dissolving 440 mg of manganese sulfate and 500 mg of vanadium trioxide in 40 mL of isopropanol to obtain a metal salt C solution with a concentration of 0.15 mmol / mL, placing the metal salt C solution and the sample B in step (2) in a reactor and stirring at 80° C. and 70 rpm for 15 minutes, and then performing a solvothermal reaction at a temperature of 160° C. for 20 hours. After the reaction is completed, the reaction is cooled to room temperature, and the material obtained in the reactor is taken out for washing and drying to obtain a preliminary sample;

[0062] (5) The preliminary sample obtained in step (4) is placed in a tubular furnace, and a mixed gas of hydrogen and argon (the volume fraction of hydrogen in the mixed gas is 10%) is introduced at a rate of 30 mL / min, and the temperature is raised to 550°C for high-temperature calcination at a rate of 18°C / min. The temperature is kept at this temperature for 6 hours to obtain a wood-derived carbon-supported metal oxide-alloy heterojunction hydrogen production catalyst.

[0063] Comparative Example 1

[0064] A method for preparing a wood-derived carbon-supported metal alloy hydrogen production catalyst, the operating steps are as follows:

[0065] (1) According to the mass ratio of wood chips, deionized water, acetic acid, and sodium chlorite being 4:130:1:1, 4 g of poplar wood chips, 130 g of deionized water, 1 g of acetic acid, and 1 g of sodium chlorite were weighed, and the poplar wood chips were heated in distilled water at 80° C. for 10 hours, and the deionized water, acetic acid, and sodium chlorite weighed above were mixed to obtain a mixed solution (this was the first time that acetic acid and chlorite were added), and the poplar wood chips heated for 10 hours were put into the mixed solution and stirred at 80° C. and 60 rpm for 1 hour, and then the same mass of acetic acid (newly weighed 1 g) and sodium chlorite (newly weighed 1 g) as the first time were added again and continued to be stirred at 80° C. and 60 rpm, and finally the wood chips were taken out and air-dried to obtain pretreated wood chips;

[0066] (2) dissolving 1.1 g of nickel sulfate in 30 mL of deionized water to obtain a metal salt A solution with a concentration of 0.23 mmol / mL, placing the wood chips pretreated in step (1) into the obtained metal salt A solution, and vacuum impregnating for 8 hours. After the impregnation is completed, the wood chips are taken out, washed, and dried to obtain impregnated wood chips;

[0067] (3) placing the wood chips obtained after impregnation in step (2) in a tube furnace, introducing argon gas at a rate of 45 mL / min, and heating the temperature to 900° C. at a rate of 5° C. / min for high temperature calcination, and keeping the temperature for 3 hours to obtain sample B;

[0068] (4) Dissolving 400 mg of ferric chloride in 30 mL of ionized water to obtain a metal salt C solution with a concentration of 0.08 mmol / mL, placing the metal salt C solution and the sample B in step (2) in a reactor, stirring at 80° C. and 64 rpm for 15 minutes, and then performing a solvothermal reaction. The reaction temperature is 150° C. and the reaction time is 24 hours. After the reaction is completed, the reaction is cooled to room temperature, and the material obtained in the reactor is taken out for cleaning and drying to obtain a preliminary sample;

[0069] (5) The preliminary sample obtained in step (4) is placed in a tubular furnace, and a mixed gas of hydrogen and argon (the volume fraction of hydrogen in the mixed gas is 12%) is introduced at a rate of 40 mL / min, and the temperature is raised to 350°C for high-temperature calcination at a rate of 12°C / min. The temperature is kept at this temperature for 5 hours to obtain a wood-derived carbon-supported metal alloy hydrogen production catalyst (-Ni3Fe / CW).

[0070] Comparative Example 2

[0071] A method for preparing a wood-derived carbon-supported metal oxide hydrogen production catalyst, the operating steps are as follows:

[0072] (1) According to the mass ratio of wood chips, deionized water, acetic acid, and sodium chlorite being 4:130:1:1, 4 g of poplar wood chips, 130 g of deionized water, 1 g of acetic acid, and 1 g of sodium chlorite were weighed, and the poplar wood chips were heated in distilled water at 80° C. for 10 hours, and the deionized water, acetic acid, and sodium chlorite weighed above were mixed to obtain a mixed solution (this was the first time that acetic acid and chlorite were added), and the poplar wood chips heated for 10 hours were put into the mixed solution and stirred at 80° C. at 65 rpm for 1 hour, and then the same mass of acetic acid (newly weighed 2 g) and sodium chlorite (newly weighed 1 g) as the first time were added again and continued to be stirred at 80° C. at 63 rpm, and finally the wood chips were taken out and air-dried to obtain pretreated wood chips;

[0073] (2) dissolving 500 mg of potassium molybdate in 40 mL of deionized water to obtain a metal salt A solution with a concentration of 0.05 mmol / mL, placing the wood chips pretreated in step (1) into the obtained metal salt A solution, and vacuum impregnating for 8 hours. After the impregnation is completed, the wood chips are taken out, washed, and dried to obtain impregnated wood chips;

[0074] (3) placing the wood chips obtained after impregnation in step (2) in a tube furnace, introducing argon gas at 35 mL / min, maintaining a heating rate of 10°C / min and raising the temperature to 800°C for high-temperature calcination, and keeping the temperature for 4 hours to obtain sample B;

[0075] (4) Sample B was placed in a tubular furnace, and a mixed gas of hydrogen and argon (the volume fraction of hydrogen in the mixed gas was 10%) was introduced at a rate of 25 mL / min. The heating rate was maintained at 15°C / min, and the temperature was raised to 450°C for high-temperature calcination. The heat preservation time was 3 hours to obtain a wood-derived carbon-supported metal oxide hydrogen production catalyst (-MoO2 / CW).

[0076] Table 1. Electrochemical hydrogen evolution performance in potassium hydroxide solution

[0077] deal with <![CDATA[-10mA / cm 2 Potential]]> Tafel slope Comparative Example 1 -149mV 128mV / dec Comparative Example 2 -211mV 179mV / dec Example 2 -45mV 76mV / dec

[0078] Table 2. Electrochemical oxygen evolution performance in potassium hydroxide solution

[0079] deal with <![CDATA[300mA / cm 2 Potential]]> Tafel slope Comparative Example 1 1.71 V 249mV / dec Comparative Example 2 2.016V 282mV / dec Example 2 1.481 V 79mV / dec

[0080] Table 1 and Table 2 are the catalysts prepared from Comparative Example 1, Comparative Example 2 and Example 2 (catalyst dosage 0.2 cm 2 ) was tested by linear sweep voltammetry (LSV) in 1.0 mol / L potassium hydroxide solution. The results are listed in the table. The catalyst reached -10 mA / cm 2 and 300mA / cm 2 The potential required for the current density is calculated and the Tafel slope is listed in the table based on the LSV. The results are as follows Figure 5 , Figure 5 , Figure 7 and Figure 8 As shown in Table 1 and Table 2, it can be seen that the wood-derived carbon-supported metal oxide-alloy heterojunction hydrogen production catalyst has good hydrogen evolution reaction and oxygen evolution reaction performance in alkaline electrolyte.

[0081] Figure 1 It can be seen that the wood-derived carbon-supported metal oxide-alloy heterojunction hydrogen production catalyst is able to form a metal alloy-metal oxide heterojunction interface. Figure 2 It can be seen that the wood-derived carbon-supported metal oxide-alloy heterojunction hydrogen production catalyst has a porous nanosheet morphology. Figure 3 It can be seen that the metal elements and oxygen elements are uniformly distributed in the wood-derived carbon-supported metal oxide-alloy heterojunction hydrogen production catalyst. Figure 4 (a) Figure 4 (b) Figure 4 (c) The material compositions of Example 2, Comparative Example 2 and Comparative Example 1 can be seen respectively. Figure 5 , Figure 6 , Figure 7 and Figure 8It can be seen that the wood-derived carbon-supported metal oxide-alloy heterojunction hydrogen production catalyst of the present invention has good hydrogen evolution reaction performance and oxygen evolution reaction performance in alkaline electrolyte, achieving -10mA / cm 2 The potential required for current density is less than 300mV, achieving 300mA / cm 2 The potential required for the current density is less than 2.1V.

[0082] Figures 5 to 8 In the figure, -Ni3Fe / MoO2 / CW is the wood-derived carbon-supported metal oxide-alloy heterojunction hydrogen production catalyst prepared in Example 2, -Ni3Fe / CW is the catalyst obtained in Comparative Example 1, and -MoO2 / CW is the catalyst obtained in Comparative Example 2.

[0083] The foregoing description of specific exemplary embodiments of the present invention is for the purpose of illustration and demonstration. These descriptions are not intended to limit the present invention to the precise form disclosed, and it is clear that many changes and variations can be made based on the above teachings. The purpose of selecting and describing the exemplary embodiments is to explain the specific principles of the present invention and its practical application, so that those skilled in the art can realize and utilize various different exemplary embodiments of the present invention and various different selections and changes. The scope of the present invention is intended to be limited by the claims and their equivalents.

Claims

1. A wood-derived carbon-supported metal oxide-alloy heterojunction hydrogen production catalyst, characterized in that: The wood-derived carbon-supported metal oxide-alloy heterojunction hydrogen production catalyst has a metal oxide-alloy heterojunction formation and is supported on a wood-derived carbon substrate; the catalyst comprises a catalytically active metal element and a non-metal element, wherein the catalytically active metal element is at least one of Ni, Fe, Mo, V, Co, W, and Cr; the non-metal element is C and / or O; wherein the active group is dispersed in the catalyst.

2. The wood-derived carbon-supported metal oxide-alloy heterojunction hydrogen production catalyst according to claim 1, characterized in that: The XRD pattern of the catalyst shows diffraction peaks belonging to wood-derived carbon, metal alloys and metal oxides.

3. The method for preparing the wood-derived carbon-supported metal oxide-alloy heterojunction hydrogen production catalyst according to any one of claims 1 to 2, characterized in that: The following steps are included: (1) heating wood chips in water, adding water, acetic acid and sodium chlorite to form a mixed solution for the first time, adding the heated wood chips into the mixed solution, and stirring at 60-70 rpm at a certain temperature, adding the same mass of acetic acid and sodium chlorite as the first time for the second time and continuing to stir at 60-70 rpm at the same temperature, and finally taking out the wood chips and air-drying them to obtain pretreated wood chips; the mass ratio of the added wood chips to the water, acetic acid and sodium chlorite added for the first time is 1-5:100-300:1-10:1-10; (2) dissolving metal salt A in a solvent to obtain a metal salt A solution, placing the wood chips pretreated in step (1) in the obtained metal salt A solution for impregnation, and after the impregnation, taking out the wood chips for washing and drying to obtain impregnated wood chips; the metal salt A is one of an iron salt, a nickel salt or a cobalt salt; (3) passing argon gas through the wood chips obtained after impregnation in step (2) and calcining them at 800-1200° C. for 1-6 hours to obtain sample B; (4) dissolving metal salt C in a solvent to obtain a metal salt C solution, placing the metal salt C solution and the sample B in step (2) in a reactor, stirring, and then performing a solvent thermal reaction. After the reaction is completed, the mixture is cooled to room temperature, and the obtained material in the reactor is taken out for cleaning and drying to obtain a preliminary sample; the solvent thermal reaction is performed at 100-200° C. for 2-48 hours; the metal salt C is obtained by mixing metal salt D and metal salt E in any proportion, wherein metal salt D is one or two of iron salt, nickel salt, and cobalt salt, which are different from the metal salt in the metal salt A solution; and metal salt E is one of molybdenum salt, vanadium salt, chromium salt, and tungsten salt; (5) The preliminary sample obtained in step (4) is introduced into a mixed gas of hydrogen and argon for high-temperature calcination at 200-900° C. for 1-6 hours to obtain a wood-derived carbon-supported metal oxide-alloy heterojunction hydrogen production catalyst.

4. The method for preparing the wood-derived carbon-supported metal oxide-alloy heterojunction hydrogen production catalyst according to claim 1, characterized in that: The mass ratio of the wood chips added in step (1) to the water, acetic acid and sodium chlorite added for the first time is 3-4:130-250:1-5:1-4; the wood chips in step (1) are one of natural woods such as pine, poplar, balsa, birch, fir, beech or eucalyptus.

5. The method for preparing the wood-derived carbon-supported metal oxide-alloy heterojunction hydrogen production catalyst according to claim 1, characterized in that: The nickel salt described in step (2) is nickel chloride, nickel acetylacetonate, nickel acetate, nickel bromide, nickel iodide, nickel sulfate, nickel nitrate, or nickel ammonium sulfate; the cobalt salt described in step (2) is one of cobalt chloride, cobalt sulfate, cobalt nitrate, cobalt carbonate, cobalt acetate, cobalt oxalate, cobalt phosphate, cobalt bromide, cobalt iodide, and cobalt sulfide; the iron salt described in step (2) is one of ferric chloride, ferric sulfate, ferric nitrate, ferric carbonate, ferric oxalate, ferric phosphate, ferric bromide, ferric iodide, ferrous sulfate, ferrous sulfate, ferrous nitrate, or ferrous chloride; and the solvents described in steps (2) and (4) are all water, methanol, ethanol, ethylene glycol, isopropanol, n-butanol, n-hexane, cyclohexane, ether, or petroleum ether.

6. The method for preparing the wood-derived carbon-supported metal oxide-alloy heterojunction hydrogen production catalyst according to claim 1, characterized in that: In step (2), the concentration of the metal salt A solution is 0.001-5 mmol / mL; in step (3), argon gas is introduced to carry out high-temperature calcination at 800-900° C., and the insulation time is 2-6 hours.

7. The method for preparing the wood-derived carbon-supported metal oxide-alloy heterojunction hydrogen production catalyst according to claim 1, characterized in that: During the stirring process described in step (4), the stirring speed is 60-70 rpm, the temperature is 80° C., and the stirring time is 15 minutes; the solvent thermal reaction is carried out at 120-180° C. for 8-20 hours; the concentrations of the metal salt D and the metal salt E in step (4) are each 0.001-10 mmol / mL.

8. The method for preparing the wood-derived carbon-supported metal oxide-alloy heterojunction hydrogen production catalyst according to claim 1, characterized in that: The nickel salt described in step (4) is nickel chloride, nickel acetylacetonate, nickel acetate, nickel bromide, nickel iodide, nickel sulfate, nickel nitrate, and ammonium nickel sulfate; the cobalt salt described in step (4) is one of cobalt chloride, cobalt sulfate, cobalt nitrate, cobalt carbonate, cobalt acetate, cobalt oxalate, cobalt phosphate, cobalt bromide, cobalt iodide, and cobalt sulfide; the iron salt described in step (4) is one of ferric chloride, ferric sulfate, ferric nitrate, ferric carbonate, ferric oxalate, ferric phosphate, ferric bromide, ferric iodide, ferrous sulfate, ferrous sulfate, ferrous nitrate, and ferrous chloride; the molybdenum salt described in step (4) is one of sodium molybdate, ammonium molybdate, and calcium molybdate. , potassium molybdate, ammonium hydrogen molybdate, ammonium phosphomolybdate, and molybdenum pentachloride; the type of the vanadium salt described in step (4) is one of vanadium sulfate, vanadium chloride, vanadium nitrate, sodium metavanadate, potassium metavanadate, vanadium pentoxide, ammonium vanadate, vanadium trioxide, and vanadyl sulfate; the type of the chromium salt described in step (4) is chromium nitrate, potassium chromate, potassium dichromate, chromium acetate, and ammonium chromate; the tungsten salt described in step (4) is one of sodium tungstate, calcium tungstate, and ammonium tungstate; the solvent described in step (4) is water, methanol, ethanol, ethylene glycol, isopropanol, n-butanol, n-hexane, cyclohexane, ether, and petroleum ether.

9. The method for preparing the wood-derived carbon-supported metal oxide-alloy heterojunction hydrogen production catalyst according to claim 1, characterized in that: The high temperature calcination in step (5) is carried out at a heating rate of 1-20°C / min, 400-600°C, and a heat preservation time of 3-6 hours; the volume fraction of hydrogen in the mixed gas is 1%-30%.

10. Use of the wood-derived carbon-supported metal oxide-alloy heterojunction hydrogen production catalyst according to any one of claims 1 to 9 in hydrogen evolution reaction and oxygen evolution reaction.

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