CN113174513B - Ni-Cu-Ti/CNTs porous composite material and preparation method thereof - Google Patents

Abstract

The invention discloses a Ni-Cu-Ti/CNTs porous composite material and a preparation method thereof. In the present invention, Ni, Cu, Ti element powders and dispersed CNTs are mixed uniformly, then ball-milled, cold-pressed to form green bodies, and then sintered to prepare porous composite materials. The porous composite material has abundant pores and uniform distribution, a simple and environmentally friendly preparation process, excellent hydrogen evolution catalytic activity and mechanical properties, and can be used for electrolytic hydrogen desorption and industrial filtration in an alkaline environment.

Description

A kind of Ni-Cu-Ti/CNTs porous composite material and preparation method thereof

technical field

The invention relates to a preparation technology of a porous material, in particular to the preparation of a Ni-Cu-Ti/CNTs (carbon nanotube, CNTs for short) porous composite material that can be used for electrolytic hydrogen desorption and industrial filtration in an alkaline environment method.

Background technique

At present, two-thirds of the world's energy demand is achieved by fossil fuels such as oil and natural gas. The main reason is that these fuels are easy to transport, store, and mine; in addition, coal also accounts for a considerable proportion of the world's energy supply. . However, these non-renewable energy sources are increasingly depleted. In order to solve the problems such as the increasing energy demand of human beings and the environmental pollution caused by energy, scientists are committed to finding new clean and renewable energy sources. The calorific value of hydrogen is two to three times that of other fuels. When hydrogen is burned, only water is produced, and no pollutants such as carbon dioxide and carbon monoxide are produced, and it does not pollute the environment. Therefore, as a clean, efficient, safe and renewable energy source, hydrogen is one of the most economical and effective alternative energy sources. The large-scale use of hydrogen energy will bring mankind into a green era of sustainable development, and large-scale and cheap hydrogen production is an important prerequisite for the development and utilization of hydrogen energy. Among the many hydrogen production methods, the advantages of water electrolysis hydrogen production technology are the most significant: the cost of hydrogen production raw materials is low, the resources are wide, the cost of water electrolysis hydrogen production equipment is low, the hydrogen purity is high, and there is no carbon emission problem. One of the most commonly used techniques for electrolytic hydrogen production is alkaline water electrolysis. However, this technique is expensive. The cost of hydrogen production from water electrolysis mainly comes from the consumption of electric energy. To achieve large-scale and cheap production of hydrogen, energy consumption must be reduced, and the most important thing is to reduce the hydrogen evolution overpotential of the electrode.

The transition metal nickel and its alloys have good chemical stability in alkaline medium, excellent corrosion resistance, and high hydrogen evolution reaction activity. They are the most widely used catalytic electrode materials for hydrogen evolution in water electrolysis. In order to improve the catalytic activity of the electrode, the development of nickel-based electrodes mainly has the following directions: (1) Porous electrodes. By increasing the real surface area of the electrode, the number of catalytic active centers is increased, and the apparent catalytic activity of the electrode is improved. Among such electrodes, Raney Ni is a typical representative. It has a low hydrogen evolution overpotential and can keep the hydrogen evolution activity unchanged for 10,000 hours. Electrolysis was carried out under the condition of current density of 2000A/ ^m2 , and the cell voltage was about 2V. However, the biggest disadvantage of this electrode is the power-off gap during the hydrogen evolution process, especially the hydrogen evolution activity after the power-off for a long time is easily lost with the oxidation and dissolution of the active components. Studies have shown that micron-scale pores can effectively prevent hydrogen from clogging the pores and make it easier for hydrogen to overflow. (2) Alloy electrodes, including Ni-metal and Ni-non-metal alloys. According to Engel-Brewer's "volcano" theory, the metal to the left of the transition system (eg Fe, Co, Ni) in which the d orbital is not filled or half filled is the same as the transition system with paired d electrons that do not bond in pure metals. When the metals on the right (such as W, Mo, Cr, La, Ha, Zr) are fused into alloys, they can have a very obvious electrocatalytic synergistic effect on the hydrogen evolution reaction, and the intrinsic catalytic activity of the electrode can be effectively improved by forming an alloy. The catalytic effect of the alloy electrode is good, but if a second phase such as graphene or carbon nanotubes is introduced into the alloy electrode to make a composite electrode, the catalytic effect of the electrode can be further optimized, and the mechanical properties of the electrode can be improved.

Carbon nanostructures can be used as catalyst supports due to their high electrical conductivity and dispersibility. Carbon nanotubes, also known as buckytubes, are one-dimensional quantum materials with a special structure (radial dimensions are in the order of nanometers, axial dimensions are in the order of micrometers, and both ends of the tube are basically sealed). The structure of CNTs is the same as the sheet structure of graphite and has good electrical properties. In addition, since the carbon atoms in CNTs adopt SP2 hybridization, compared with SP3 hybridization, the S orbital composition in SP2 hybridization is relatively large, which makes CNTs have high modulus, high strength, and excellent mechanical properties.

Therefore, this study considers adding an appropriate amount of CNTs to the Ni-Cu-Ti alloy porous electrode to prepare a composite electrode to further improve the hydrogen evolution performance and electrode lifetime. By mixing the alloy powder and CNTs uniformly and then sintering together, the CNTs are dispersed and distributed in the Ni-Cu-Ti porous material, which acts as a catalytic carrier during the electrolysis process, and has high conductivity, which greatly improves the intrinsic catalysis of the composite electrode. active.

SUMMARY OF THE INVENTION

The invention provides an effective composite porous electrode material for hydrogen desorption and industrial filtration under alkaline environment, which has abundant pores, large specific surface area, excellent electrocatalytic activity, corrosion resistance and chemical stability. and excellent mechanical properties. The invention discloses a Ni-Cu-Ti/CNTs porous composite material and a preparation method thereof.

The preparation steps of a Ni-Cu-Ti/CNTs porous composite material are as follows:

1) Weigh the four powders of Ni, Cu, Ti, and CNTs according to a certain mass ratio.

2) Add the weighed CNTs powder to deionized water at a content of 0.3 g/L, and add sodium dodecyl sulfosulfate (SDS) at a concentration of 2 × 10 ^-3 mol/L, and place the mixed solution in a Ultrasonic dispersion treatment in ultrasonic cleaning machine for 30min;

3) Mix the weighed Ni, Cu and Ti powders into the ultrasonically dispersed solution, and place it on a magnetic stirrer to stir until the solution is layered;

4) Vacuum filter the stirred solution to obtain the separated powder, and then dry the powder for 5h;

5) Ball milling the dried powder, drying and sieving after the ball milling, and then adding 3%~5% stearic acid relative to the mass of the powder and drying for 5 hours;

6) Sieve the dried powder with a 60-mesh sieve, and take the sieved powder for later use;

7) Put the sieved powder into the mold, and press it into a powder green body under the hydraulic press;

8) The pressed powder green body is placed in a vacuum furnace for sintering, and the vacuum degree is not less than 2×10 ^-3 Mpa; the sintering process is: ① The temperature rises from room temperature to 300°C at a heating rate of 4~6°C/min; ②Insulation for 50~70min; ③Raise to 600℃ with a heating rate of 4~6℃/min; ④Incubate for 50~70min; ⑤Raise to 900℃ with a heating rate of 4~6℃/min; ⑦ Raising the temperature to 1000 ℃ at a heating rate of 2-3 ℃/min; ⑧ keeping the temperature for 50-70 min; ⑨ cooling to room temperature with the furnace to obtain the porous composite material.

The present invention adopts the advantages of the above technical solutions as follows:

(1) The porous composite material has a large specific surface area and high porosity. The above technical solution makes the element powder form a uniform and connected pore structure in the sintering process through the element sintering method, and the porosity is rich and the pores are large, which increases the specific surface area of the material surface and is beneficial to ensure the realization of the filtration function of the composite material. .

(2) The porous composite material has high catalytic activity. The above scheme adds CNTs. Due to its high conductivity and dispersibility, carbon nanostructures can be used as catalyst carriers. In addition, the synergistic catalysis between Ni, Cu, and Ti elements, as well as large specific surface area and high porosity, make the The porous composite material has the effect of adsorption and desorption of ions in the process of electrolytic hydrogen desorption, which makes the composite material have high hydrogen evolution catalytic activity.

(3) The raw materials of the porous composite material are readily available, and the preparation process is simple. The whole process of preparation is kept green and environmentally friendly, and no pollutants are produced. The raw materials are readily available, the cost is low, and the preparation process is simple and can be mass-produced.

(4) The porous composite material has excellent mechanical properties and corrosion resistance. The above scheme is prepared by mixing Ni, Cu, Ti, and CNTs powders and then sintering. The addition of CNTs makes the composite material have high modulus, high strength, and excellent mechanical properties. In addition, after the reaction of the element powder, a corrosion-resistant product will be obtained, which ensures that the material has excellent mechanical properties and corrosion resistance, and greatly prolongs the service life of the material.

Description of drawings

Figure 1 shows the surface topography of the Ni-Cu-Ti/CNTs porous composite prepared in Example 1.

Figure 2 shows the cathodic polarization curve of the Ni-Cu-Ti/CNTs porous composite prepared in Example 1.

Detailed ways

The present invention will be further described below with reference to specific embodiments, but the present invention is not limited to these embodiments.

Example 1

Three high-purity powders of Ni, Cu, Ti, and CNTs were weighed according to a certain mass ratio. The Ni powder content was 55%wt, and the powder particle size was 5μm; the Cu powder content was 35%wt, and the powder particle size was 5μm; Ti The powder content is 10%wt, the powder particle size is 5μm, and the CNTs content is 0.3%wt. It is a multi-walled carbon nanotube with a length of 1μm. The weighed CNTs were added to deionized water at a ratio of 0.1 g/L, and 68% of sodium dodecylbenzenesulfonate, 150% of Tween-20, and 150% of polystyrene were added relative to the mass of CNTs. Vinylpyrrolidone, the mixed solution was placed in an ultrasonic cleaner for ultrasonic dispersion for 30min. After ultrasonication, the weighed Ni, Cu, and Ti powders were added and stirred on a magnetic stirrer until the solution was separated into layers. After stirring, carry out vacuum filtration, place the separated powder in a vacuum drying box at 75 degrees for drying for 5 hours, put the dried powder into a ball mill, add alcohol ball mill, the ratio of ball to material is 12:1, and the rotation speed is 180r/ min, ball milling time 16h, dry and sieve powder after ball milling. Then add 5% stearic acid relative to the powder mass, and then dry in a vacuum drying oven at 75 degrees for 5 hours. Sieve the dried powder through a 60-mesh sieve. Put the sieved powder into the mold, press the green cuboid powder under the pressure of 200Mpa under the hydraulic press, and hold the pressure for 90s. The prepared powder green body was placed in a vacuum for sintering, and the vacuum degree was 2×10 ^-4 Mpa; the sintering process was as follows: ①Rising from room temperature to 300℃ at a heating rate of 5℃/min; ②Keeping temperature for 60min; The heating rate of ℃/min was raised to 600°C; ④The temperature was kept for 60min; 9. The porous composite metal material is obtained by cooling to room temperature with the furnace.

The open porosity of the obtained material is 42.57%, which is relatively high. The microscopic surface morphology is shown in Figure 1. It can be seen that the prepared material has many pores and abundant pores.

In order to study the catalytic hydrogen evolution performance of the prepared porous composites, the prepared samples were sealed with PTFE and silicone rubber, and the exposed area of the electrode surface was 1.1 cm ² , and electrochemical tests were performed in 6Mol/L KOH solution. A standard three-electrode system was used, the auxiliary electrode was Pt sheet, the reference electrode was Hg, HgO/OH ^- , and the working electrode was the prepared Ni-Cu-Ti/CNTs porous composite electrode sample. The instrument used for the test was CS350 electrochemical workstation, the scanning rate was 4mV/s, the scanning range was 0V~-2V, and the electrolyte was kept in a constant temperature water bath at 25℃. The cathodic polarization curve of the Ni-Cu-Ti/CNTs porous composite is shown in Figure 2. When the current density is 399 mA/cm ² , the overpotential is 750 mV (vs. Hg/HgO).

Example 2

Three high-purity powders of Ni, Cu, Ti, and carbon nanotubes were weighed according to a certain mass ratio, wherein the Ni powder content was 56%wt, the powder particle size was 4μm; the Cu powder content was 33%wt, and the powder particle size was 4μm ; Ti powder content of 11%wt, powder particle size of 4μm, CNTs content of 0.4%wt, is a multi-walled carbon nanotube with a length of 2μm. The weighed CNTs were added to deionized water at a ratio of 0.1 g/L, and 68% of sodium dodecylbenzenesulfonate, 150% of Tween-20, and 150% of polystyrene were added relative to the mass of CNTs. Vinylpyrrolidone, the mixed solution was placed in an ultrasonic cleaner for ultrasonic dispersion treatment for 30min. After ultrasonication, the weighed Ni, Cu, and Ti powders were added and stirred on a magnetic stirrer until the solution was separated into layers. After stirring, carry out vacuum filtration, put the separated powder in a vacuum drying box at 75 degrees to dry for 5 hours, put the dried powder into a ball mill, add alcohol ball mill, the ratio of ball to material is 12:1, and the rotation speed is 200r/ min, ball milling time 17h, dry and sieve powder after ball milling. Then add 4% stearic acid relative to the powder mass, and then dry in a vacuum drying oven at 75 degrees for 5 hours. Sieve the dried powder through a 60-mesh sieve. Put the sieved powder into the mold, press the green cuboid powder under the pressure of 200Mpa under the hydraulic press, and hold the pressure for 100s. The prepared powder green body was placed in a vacuum molybdenum sheet furnace for sintering, and the vacuum degree was 2×10 ^-4 Mpa; the sintering process was as follows: (1) Raising the temperature from room temperature to 300°C at a heating rate of 5°C/min; (2) maintaining the temperature for 60 minutes; ③Rise to 600°C at a heating rate of 5°C/min; ④Incubate for 60 minutes; ⑤Rise to 900°C at a heating rate of 5°C/min; ⑧ heat preservation for 60 minutes; ⑨ cooling to room temperature with the furnace to obtain the porous composite metal material.

The sample preparation process and electrochemical experiment steps in Example 1 were repeated, and the pore structure and electrochemical performance similar to those in Example 1 were obtained.

Example 3

Three high-purity powders of Ni, Cu, Ti, and CNTs were weighed according to a certain mass ratio. The Ni powder content was 59%wt, and the powder particle size was 3μm; the Cu powder content was 33%wt, and the powder particle size was 3μm; Ti The powder content is 8% wt, the powder particle size is 3 μm, and the CNTs content is 0.5%. It is a multi-walled carbon nanotube with a length of 0.5 μm. The weighed CNTs were added to deionized water at a ratio of 0.1 g/L, and 68% sodium dodecylbenzenesulfonate, 150% Tween-20, and 150% polyethylene were added to the CNTs, respectively. Pyrrolidone, the mixed solution was placed in an ultrasonic cleaner for ultrasonic dispersion treatment for 30min. After ultrasonication, the weighed Ni, Cu, and Ti powders were added and stirred on a magnetic stirrer until the solution was separated into layers. After stirring, carry out vacuum filtration, place the separated powder in a vacuum drying oven at 75 degrees to dry for 5 hours, put the dried powder into a ball mill, add alcohol ball mill, the ratio of ball to material is 12:1, and the rotation speed is 210r/ min, ball milling time 18h, dry and sieve powder after ball milling. Then add 3% stearic acid relative to the powder mass, and then dry in a vacuum drying oven at 75 degrees for 5 hours. Sieve the dried powder through a 60-mesh sieve. Put the sieved powder into the mold, press the green cuboid powder under the pressure of 200Mpa under the hydraulic press, and hold the pressure for 110s. The prepared powder green body was placed in a vacuum furnace for sintering, and the vacuum degree was 2×10 ^-4 Mpa; the sintering process was as follows: (1) Raising the temperature from room temperature to 300°C at a heating rate of 5°C/min; (2) holding the temperature for 60 minutes; (3) using The heating rate of 5°C/min is raised to 600°C; ④The temperature is kept for 60 minutes; ⑤The temperature is raised to 900°C with the heating rate of 5°C/min; 60min; ⑨ cooling to room temperature with the furnace to obtain the porous composite metal material.

Example 4

Three high-purity powders of Ni, Cu, Ti, and CNTs were weighed according to a certain mass ratio. The Ni powder content was 55%wt, and the powder particle size was 5μm; the Cu powder content was 33%wt, and the powder particle size was 5μm; Ti The powder content is 12%wt, the powder particle size is 5μm, and the CNTs content is 0.35%, which are multi-walled carbon nanotubes with a length of 1.5μm. The weighed CNTs were added to deionized water at a ratio of 0.1 g/L, and 68% of sodium dodecylbenzenesulfonate, 150% of Tween-20, and 150% of polystyrene were added relative to the mass of CNTs. Vinylpyrrolidone, the mixed solution was placed in an ultrasonic cleaner for ultrasonic dispersion treatment for 30min. After ultrasonication, the weighed Ni, Cu, and Ti powders were added and stirred on a magnetic stirrer until the solution was separated into layers. After stirring, carry out vacuum filtration, place the separated powder in a vacuum drying oven at 75 degrees to dry for 5 hours, put the dried powder into a ball mill, add alcohol ball mill, the ratio of ball to material is 12:1, and the rotation speed is 190r/ min, ball milling time 15h, dry and sieve powder after ball milling. Then add 5% stearic acid relative to the powder mass, and then dry in a vacuum drying oven at 75 degrees for 5 hours. Sieve the dried powder through a 60-mesh sieve. Put the sieved powder into the mold, press the green cuboid powder under the pressure of 200Mpa under the hydraulic press, and hold the pressure for 100s. The powder green body prepared is placed in a vacuum furnace for sintering, and the vacuum degree is 2×10 ^-4 Mpa; the sintering process is as follows: (1) Raise the temperature from room temperature to 300°C at a heating rate of 5°C/min; (2) keep the temperature for 60 minutes; (3) use The heating rate of 5°C/min was raised to 600°C; ④The temperature was kept for 60min; 60min; ⑨ cooling to room temperature with the furnace to obtain the porous composite metal material.

The sample preparation process and electrochemical experiment steps in Example 1 were repeated, and the pore structure and electrochemical performance similar to those in Example 1 were obtained.

Example 5

Three kinds of high-purity powders of Ni, Cu, Ti, and carbon nanotubes are weighed according to a certain mass ratio, wherein the Ni powder content is 55%wt, the powder particle size is 5μm; the Cu powder content is 35%wt, the powder particle size is 5μm ; Ti powder content of 10%wt, powder particle size of 5μm, CNTs content of 0.5%, is a multi-walled carbon nanotube with a length of 2μm. The weighed CNTs were added to deionized water at a ratio of 0.1 g/L, and 68% of sodium dodecylbenzenesulfonate, 150% of Tween-20, and 150% of polystyrene were added relative to the mass of CNTs. Vinylpyrrolidone, the mixed solution was placed in an ultrasonic cleaner for ultrasonic dispersion for 30min. After ultrasonication, the weighed Ni, Cu, and Ti powders were added and stirred on a magnetic stirrer until the solution was separated into layers. After stirring, carry out vacuum filtration, place the separated powder in a vacuum drying oven at 75 degrees to dry for 5 hours, put the dried powder into a ball mill, add alcohol ball mill, the ratio of ball to material is 12:1, and the rotation speed is 190r/ min, ball milling time 15h, dry and sieve powder after ball milling. Then add 3% stearic acid relative to the powder mass, and then dry in a vacuum drying oven at 75 degrees for 5 hours. Sieve the dried powder through a 60-mesh sieve. Put the sieved powder into the mold, press the green cuboid powder under the pressure of 200Mpa under the hydraulic press, and hold the pressure for 120s. The powder green body prepared is placed in a vacuum furnace for sintering, and the vacuum degree is 2×10 ^-4 Mpa; the sintering process is as follows: (1) Raise the temperature from room temperature to 300°C at a heating rate of 5°C/min; (2) keep the temperature for 60 minutes; (3) use The heating rate of 5°C/min was raised to 600°C; ④The temperature was kept for 60min; 60min; ⑨ cooling to room temperature with the furnace to arrive at the porous composite metal material.

The sample preparation process and electrochemical experiment steps in Example 1 were repeated, and the pore structure and electrochemical performance similar to those in Example 1 were obtained.

The above is only a preferred embodiment of the present invention, and does not limit the present invention in any form. Any simple modifications, equivalent changes and modifications made to the above embodiments according to the technical essence of the present invention belong to the present invention. within the scope of the technical solution.

Claims (5)

1. a Ni-Cu-Ti/CNTs porous composite material, is characterized in that: has added carbon nanotube CNTs, utilizes the outstanding electrical conductivity and adsorption characteristic of CNTs, improves the electrolytic hydrogen desorption ability of material, and its preparation step is as follows: 1) Weigh the four powders of Ni, Cu, Ti and CNTs according to a certain mass ratio, in which the percentage of Ti powder is 8%~12wt%, the percentage of Cu powder is 33%~37wt%, and the percentage of CNTs is 0.3%~0.5wt% %, the rest are Ni; 2) Add the weighed CNTs powder to deionized water at a content of 0.3 g/L, and add sodium dodecyl sulfate SDS at a concentration of 2 × 10 ^-3 mol/L, and place the mixed solution in ultrasonic cleaning. Ultrasonic dispersion treatment in the machine for 30min; 3) Mix the weighed Ni, Cu and Ti powders into the ultrasonically dispersed solution, and place it on a magnetic stirrer to stir until the solution is layered; 4) Vacuum filter the stirred solution to obtain the separated powder, and then dry the powder for 5h; 5) Ball milling the dried powder, drying and sieving after the ball milling, and then adding 3%~5% stearic acid relative to the mass of the powder and drying for 5 hours; 6) Sieve the dried powder with a 60-mesh sieve, and take the sieved powder for later use; 7) Put the sieved powder into the mold, and press it into a powder green body under the hydraulic press; 8) The pressed powder green body is placed in a vacuum furnace for sintering, and the vacuum degree is not lower than 2×10 ^-3 Pa; 50~70min; rise to 600°C at a heating rate of 4~6°C/min; hold for 50~70min; rise to 900°C at a heating rate of 4~6°C/min; hold for 50~70min; hold at 2~3°C/min The heating rate of min is increased to 1000° C.; the temperature is maintained for 50-70 min; and the porous composite material is obtained by cooling to room temperature with the furnace. 2. The Ni-Cu-Ti/CNTs porous composite material according to claim 1, characterized in that in step 1), the particle size of Ni is 3-5 μm, the particle size of Cu is 3-5 μm, and the particle size of Ti is 3-5 μm. The diameter of the CNTs is 3-5 μm, and the CNTs are multi-walled carbon nanotubes with a length of 0.5-2 μm. 3. a preparation method of Ni-Cu-Ti/CNTs composite porous material, it is characterized in that: add CNTs, utilize the outstanding electrical conductivity and adsorption characteristic of CNTs, improve the electrolytic hydrogen desorption ability of material, and its preparation step is as follows: 1) Weigh the four powders of Ni, Cu, Ti and CNTs according to a certain mass ratio, in which the percentage of Ti powder is 8%~12wt%, the percentage of Cu powder is 33%~37wt%, and the percentage of CNTs is 0.3%~0.5wt% %, the rest are Ni; 2) Add the weighed CNTs powder to deionized water at a content of 0.3 g/L, and add sodium dodecyl sulfate SDS at a concentration of 2 × 10 ^-3 mol/L, and place the mixed solution in ultrasonic cleaning. Ultrasonic dispersion treatment in the machine for 30min; 3) Mix the weighed Ni, Cu and Ti powders into the ultrasonically dispersed solution, and place it on a magnetic stirrer to stir until the solution is layered; 4) Vacuum filter the stirred solution to obtain the separated powder, and then dry the powder for 5h; 5) Ball milling the dried powder, drying and sieving after the ball milling, and then adding 3%~5% stearic acid relative to the mass of the powder and drying for 5 hours; 6) Sieve the dried powder with a 60-mesh sieve, and take the sieved powder for later use; 7) Put the sieved powder into the mold, and press it into a powder green body under the hydraulic press; 8) The pressed powder green body is placed in a vacuum furnace for sintering, and the vacuum degree is not lower than 2×10 ^-3 Pa; 50~70min; rise to 600°C at a heating rate of 4~6°C/min; hold for 50~70min; rise to 900°C at a heating rate of 4~6°C/min; hold for 50~70min; hold at 2~3°C/min The heating rate of min is increased to 1000° C.; the temperature is maintained for 50-70 min; and the porous composite material is obtained by cooling to room temperature with the furnace. 4. The preparation method of Ni-Cu-Ti/CNTs porous composite material according to claim 3, characterized in that in step 5), the ball-to-material ratio of the ball milling is 12:1, the ball milling rotational speed is 180-210 r/min, and the ball milling The time is 15~18h. 5. The preparation method of the Ni-Cu-Ti/CNTs porous composite material according to claim 3, characterized in that in step 7), the pressure of the hydraulic press is 180-220 MPa, and the holding time is 90-120 s.

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