CN116213743A - Preparation method of selenium/tellurium doped copper-nickel nanowire - Google Patents

Abstract

The invention discloses a preparation method of a selenium/tellurium-doped copper-nickel nanowire, which comprises the following steps: 1) Placing a copper precursor, a nickel precursor and a surfactant in an organic solvent, and stirring in an inert gas atmosphere at a proper temperature until the solutions are uniformly mixed; 2) Maintaining stirring, raising the temperature to a first reaction temperature and heating for a period of time; 3) Continuously stirring the solution, and heating to the second reaction temperature again and for a period of time; 4) Dissolving a certain amount of selenium/tellurium powder in oleylamine, and performing ultrasonic dispersion to obtain a selenium/tellurium powder solution for later use; 5) After the reactor is cooled, adding selenium/tellurium powder solution, stirring under inert atmosphere, heating to a third reaction temperature again, and heating for a period of time; 6) And after the reactor is cooled, washing the product for multiple times, centrifuging, and vacuum drying to obtain the selenium/tellurium doped copper-nickel nanowire catalyst. The CuNiSe nanowire catalyst is uniformly distributed and has a neat shape, and the diameter of the nanowire is 30-60 nanometers.

Description

A kind of preparation method of selenium/tellurium doped copper-nickel nanowire

technical field

The invention belongs to the technical field of catalyst synthesis, and in particular relates to a preparation method of selenium/tellurium doped copper-nickel nanowires.

Background technique

With the advancement of technology and the consumption of fossil fuels, human beings urgently need to find a more sustainable energy source. Hydrogen production by electrolysis of water provides a new direction for the development of sustainable energy due to its high efficiency, no need to consume fossil energy, and high product purity. In recent years, noble metals represented by platinum have shown excellent performance as catalytic materials in the hydrogen evolution reaction of electrolyzed water. However, high cost and low reserves are the main obstacles restricting the large-scale application of this technology. Therefore, how to develop non-precious metal catalysts with high hydrogen production efficiency and low cost has become a research hotspot in the field of catalysis.

At present, copper-nickel-based non-noble metal catalysts are widely concerned because of their high conductivity and low cost. For example, the patent publication number CN113913859A discloses a cobalt-doped copper-nickel-based alloy catalyst for hydrogen evolution reaction, which has a good Electrocatalytic performance. Similarly, Chinese Patent Publication No. CN114420956A discloses a carbon-doped copper-nickel-based alloy catalyst for direct methanol fuel cell anode electrocatalysis. The above works are all reports on changing the types of elements doped in copper-nickel-based alloys, but there are few reports on the preparation strategy of selenium/tellurium-doped copper-nickel-based nanowire catalysts. Therefore, there is an urgent need to develop a facile and general method to synthesize Se/Te-doped CuNi-based nanowire catalysts.

Contents of the invention

The technical problem to be solved by the present invention is to provide a preparation method of selenium/tellurium-doped copper-nickel nanowires; the preparation method can precisely control the composition of selenium-doped copper-nickel-based nanowires by changing the amount of selenium/tellurium powder added. The CuNiSe nanowire catalyst with uniform distribution and neat appearance is prepared, and the diameter of the nanowire is 30-60 nanometers.

In order to solve the problems of the technologies described above, the present invention adopts the following technical solutions:

A preparation method of selenium/tellurium-doped copper-nickel-based nanowire catalyst, comprising the steps of:

1) Put the copper precursor, the nickel precursor and the surfactant in an organic solvent, stir in an inert gas atmosphere and at a suitable temperature until the solution is evenly mixed;

2) keep stirring, the temperature is raised to the first reaction temperature and heated for a period of time;

3) The solution is continuously stirred, and the temperature is raised to the second reaction temperature again and heated for a period of time;

4) Take a certain amount of selenium/tellurium powder and dissolve it in oleylamine, and disperse it ultrasonically to obtain a selenium/tellurium powder solution for subsequent use;

5) After the reactor cools down, slowly add the selenium/tellurium powder solution, keep stirring under an inert atmosphere and heat up to the third reaction temperature again and heat for a period of time;

6) After the reactor is cooled, the product is washed several times, then centrifuged, and vacuum-dried to obtain a selenium/tellurium-doped copper-nickel nanowire catalyst.

As a further improvement of the technical scheme, in step 1), the precursor of the copper is copper acetylacetonate, the precursor of the nickel is nickel chloride hexahydrate, and the surfactant is dimethyl dioctadecyl Ammonium chloride; the molar ratio of the copper precursor, the nickel precursor and the surfactant is 1-2:1:1-1.5.

Preferably, in step 1), the organic solvent is oleylamine, and the ratio of the amount of the copper precursor to the organic solvent is 0.8mmol/8-10mL.

Preferably, in step 1), the inert gas is nitrogen or argon.

Preferably, in step 1), the appropriate temperature is 60-90°C, and the stirring time is 30-90min.

As a further improvement of the technical solution, in step 2), the first reaction temperature is 170-190° C., and the period of time is 200-300 min.

As a further improvement of the technical solution, in step 3), the second reaction temperature is 200-250° C., and the period of time is 60-100 min.

As a further improvement of the technical solution, in step 4), the mass concentration of the selenium/tellurium powder solution is 2-5g/L.

Preferably, in step 4), the conditions for the ultrasonic dispersion are: 1-5 minutes of ultrasonication at 40%-80% of 400W power.

As a further improvement of the technical solution, in step 5), the temperature is lowered to 30-70°C, the third reaction temperature is 70-110°C, and the period of time is 60-90min.

Preferably, in step 5), the inert atmosphere is nitrogen or argon.

As a further improvement of the technical solution, in step 6), the washing solvent is ethanol or n-hexane.

Preferably, in step 6), the rotational speed of the centrifugation is 5000-9000r, and the time is 5-10min.

Preferably, in step 6), the temperature of the vacuum drying is 40-110°C, and the time is 8-24h.

Preferably, in step 6), the vacuum degree of the vacuum drying is 0.08-0.1 MPa.

Any range recited in the present invention includes the endpoints and any value between the endpoints and any sub-range formed by the endpoints or any value between the endpoints.

Unless otherwise specified, each raw material in the present invention can be purchased commercially, and the equipment used in the present invention can be carried out by using conventional equipment in the field or referring to the prior art in the field.

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

The preparation method of the invention adopts a wet chemical method and a simple oil phase synthesis to successfully prepare the selenium/tellurium doped copper-nickel nanowire catalyst. By changing the amount of selenium powder or tellurium powder added, the composition of the nanotube catalyst can be precisely regulated; TEM and HAADF-STEM confirmed the nanowire structure of the nanocatalyst, and the diameter of the nanowire is 30-60 nanometers; according to EDX element According to the distribution diagram and XRD results, CuNiSe and CuNiTe exist in the form of alloy in the nanowire catalyst, and copper exists in an amorphous structure through XPS; the special selenium/tellurium doped copper-nickel nanowire structure plays an important role in the electrocatalytic hydrogen evolution reaction has potential application prospects.

Description of drawings

Below in conjunction with accompanying drawing, specific embodiment of the present invention is described in further detail

Fig. 1 is the transmission electron microscope figure that embodiment 1 makes sample;

Fig. 2 is the high-angle annular dark field imaging figure of the sample that embodiment 1 makes;

Fig. 3 is the elemental analysis figure of the sample that embodiment 1 makes;

Fig. 4 is the X-ray diffractogram of the sample that embodiment 1 makes;

Fig. 5 is the X-ray photoelectron spectrum of the sample that embodiment 1 makes;

Fig. 6 is the Cu element X-ray photoelectron spectrum of the sample that embodiment 1 makes;

Fig. 7 is the Ni element X-ray photoelectron spectrum of the sample that embodiment 1 makes;

Fig. 8 is the Se element X-ray photoelectron spectrum of the sample that embodiment 1 makes;

Fig. 9 is the O element X-ray photoelectron spectrum of the sample that embodiment 1 makes;

Fig. 10 is the C element X-ray photoelectron spectrum of the sample that embodiment 1 makes;

Fig. 11 is the X-ray diffraction figure of the sample that embodiment 2 makes;

Fig. 12 is the transmission electron microscope figure of the sample that embodiment 2 makes;

Fig. 13 is the transmission electron microscope picture of the sample that comparative example 1 makes;

FIG. 14 is a transmission electron microscope image of the sample prepared in Comparative Example 2.

Detailed ways

In order to illustrate the present invention more clearly, the present invention will be further described below in conjunction with preferred embodiments. Those skilled in the art should understand that the content specifically described below is illustrative rather than restrictive, and should not limit the protection scope of the present invention.

As an aspect of the present invention, a method for preparing a selenium/tellurium-doped copper-nickel-based nanowire catalyst of the present invention comprises the following steps:

1) Put the copper precursor, the nickel precursor and the surfactant in an organic solvent, stir in an inert gas atmosphere and at a suitable temperature until the solution is evenly mixed;

2) keep stirring, the temperature is raised to the first reaction temperature and heated for a period of time;

3) The solution is continuously stirred, and the temperature is raised to the second reaction temperature again and heated for a period of time;

4) Take a certain amount of selenium/tellurium powder and dissolve it in oleylamine, and disperse it ultrasonically to obtain a selenium/tellurium powder solution for subsequent use;

5) After the reactor cools down, slowly add the selenium/tellurium powder solution, keep stirring under an inert atmosphere and heat up to the third reaction temperature again and heat for a period of time;

6) After the reactor is cooled, the product is washed several times, then centrifuged, and vacuum-dried to obtain a selenium/tellurium-doped copper-nickel nanowire catalyst.

In some embodiments of the present invention, in step 1), the precursor of the copper is copper acetylacetonate, the precursor of the nickel is nickel chloride hexahydrate, and the surfactant is dimethyl didecyl Octyl ammonium chloride; the molar ratio of the copper precursor, the nickel precursor and the surfactant is 1-2:1:1-1.5.

In some embodiments of the present invention, in step 1), the organic solvent is oleylamine, and the ratio of the copper precursor to the organic solvent is 0.8mmol/8-10mL.

In some embodiments of the present invention, in step 1), the inert gas is nitrogen or argon.

In some embodiments of the present invention, in step 1), the appropriate temperature is 60-90° C., and the stirring time is 30-90 min.

In some embodiments of the present invention, in step 2), the first reaction temperature is 170-190° C., and the period of time is 200-300 min.

In some embodiments of the present invention, in step 3), the second reaction temperature is 200-250° C., and the period of time is 60-100 min.

In some embodiments of the present invention, in step 4), the mass concentration of the selenium/tellurium powder solution is 2-5g/L.

In some embodiments of the present invention, in step 4), the condition of the ultrasonic dispersion is: ultrasonic for 1-5 min at 40%-80% of 400W power.

In some embodiments of the present invention, in step 5), the temperature is lowered to 30-70°C, the third reaction temperature is 70-110°C, and the period of time is 60-90min.

In some embodiments of the present invention, in step 5), the inert atmosphere is nitrogen or argon.

In some embodiments of the present invention, in step 6), the washing solvent is ethanol or n-hexane.

In some embodiments of the present invention, in step 6), the centrifugation speed is 5000-9000r, and the time is 5-10min.

In some embodiments of the present invention, in step 6), the temperature of the vacuum drying is 40-110° C., and the time is 8-24 hours.

In some embodiments of the present invention, in step 6), the vacuum degree of the vacuum drying is 0.08-0.1 MPa.

Example 1

A preparation method of selenium-doped copper-nickel-based nanowire catalyst, comprising the steps of:

1) Put 0.2094g copper acetylacetonate, 0.0951g nickel chloride hexahydrate and 0.3g dimethyl dioctadecyl ammonium chloride in 8mL oleylamine, stir at 80°C for 50min in a nitrogen atmosphere, until The solution is mixed evenly;

2) Stir continuously, and heat up to the first reaction temperature of 185°C, and heat for 220min;

3) The solution is continuously stirred, and the temperature is raised to the second reaction temperature again and heated for a period of time;

4) Dissolve 5 mg of selenium powder in 2 mL of oleylamine, and disperse it ultrasonically to obtain a 2.5 g/L selenium powder solution, which is set aside;

5) When the temperature of the three-necked flask is lowered to 50°C, slowly add the selenium powder solution dropwise, keep stirring under the _N2 atmosphere, and then heat up to 100°C for 60 minutes;

6) the three-necked flask is cooled to room temperature, and the initial product obtained is washed several times with a mixed solvent of ethanol and n-hexane,

After centrifugation and drying, a selenium-doped copper-nickel-based nanowire catalyst is obtained.

Fig. 1 has shown the transmission electron micrograph of the sample that embodiment 1 makes;

Fig. 2 has shown the high-angle annular dark field imaging figure of the sample that embodiment 1 makes;

Fig. 3 has shown the elemental analysis figure of the sample that embodiment 1 makes;

Fig. 4 shows the X-ray diffraction figure of the sample that embodiment 1 makes;

Fig. 5 is the X-ray photoelectron spectrum of the sample that embodiment 1 makes;

Fig. 6 is the Cu element X-ray photoelectron spectrum of the sample that embodiment 1 makes;

Fig. 7 is the Ni element X-ray photoelectron spectrum of the sample that embodiment 1 makes;

Fig. 8 is the Se element X-ray photoelectron spectrum of the sample that embodiment 1 makes;

Fig. 9 is the O element X-ray photoelectron spectrum of the sample that embodiment 1 makes;

FIG. 10 is the C element X-ray photoelectron spectrum of the sample prepared in Example 1.

After testing, the selenium-doped copper-nickel-based nanowires prepared in this embodiment have a diameter of 30-60 nanometers.

Example 2

A method for preparing a tellurium-doped copper-nickel-based nanowire catalyst, comprising the steps of:

Repeat Example 1, the difference is only: in step 3), take 5 mg of tellurium powder; in step 4), add the tellurium powder solution into the three-necked flask.

Fig. 11 is the X-ray diffraction figure of the sample that embodiment 2 makes;

Fig. 12 is the transmission electron microscope figure of the sample that embodiment 2 makes;

After testing, the tellurium-doped copper-nickel-based nanowires prepared in this embodiment have a diameter of 30-60 nanometers.

Comparative example 1

A preparation method of selenium-doped copper-nickel-based nanowire catalyst, comprising the steps of:

Repeat Example 1, its difference is only: in step 3), the mass concentration of selenium powder solution is 1g/L.

FIG. 13 is a transmission electron microscope image of CuNiSe nanowires prepared in this comparative example.

It was detected that the surface of the selenium-doped copper-nickel-based nanowires prepared in this example had obvious mottling, and no selenium-doped copper-nickel-based nanowires with a smooth surface and uniform distribution were obtained.

It can be seen that when the quality of the selenium/tellurium powder solution is too low, it is impossible to uniformly dope selenium/tellurium on the surface of the copper-nickel base.

Comparative example 2

A method for preparing a tellurium-doped copper-nickel-based nanowire catalyst, comprising the steps of:

Repeat Example 2, the difference is only: in step 3), the mass concentration of the tellurium powder solution is 6g/L.

FIG. 14 is a transmission electron microscope image of CuNiTe nanowires prepared in this comparative example.

After testing, the tellurium-doped copper-nickel-based nanowires prepared in this comparative example had a large number of nanoclusters of different sizes, and no nanowires with regular shapes were obtained.

It can be seen that when the mass concentration of the selenium/tellurium powder solution is too high, nanowires with regular shapes cannot be obtained.

Comparative example 3

A preparation method of selenium-doped copper-nickel-based nanowire catalyst, comprising the steps of:

Repeat Example 1, the only difference is: in step 1, the precursor of copper is copper nitrate, and the precursor of nickel is nickel nitrate.

After testing, this comparative example cannot make selenium-doped copper-nickel-based nanowires

It can be seen that when the copper precursor and the nickel precursor used are not suitable, the selenium-doped copper-nickel-based nanowires with regular morphology and uniform dispersion cannot be obtained.

Comparative example 4

A preparation method of selenium-doped copper-nickel-based nanowire catalyst, comprising the steps of:

Repeat Example 1, the only difference is: in step 2, the temperature is raised to 150°C.

After testing, the selenium-doped copper-nickel-based nanowires prepared in this comparative example present a large number of massive agglomerated particles

It can be seen that when the first reaction temperature is too low, evenly distributed and complete selenium-doped copper-nickel-based nanowires cannot be obtained.

Comparative example 5

A preparation method of selenium-doped copper-nickel-based nanowire catalyst, comprising the steps of:

Repeat Example 1 except that step 2) is omitted.

After testing, this comparative example cannot make selenium-doped copper-nickel-based nanowires

It can be seen that when step 2) is canceled and the reaction temperature is directly raised to the second reaction temperature to start the reaction, selenium-doped copper-nickel-based nanowires cannot be prepared.

In summary, in the preparation method of a selenium/tellurium-doped copper-nickel-based nanowire catalyst of the present invention, the reaction temperature, reaction atmosphere, solution volume, amount of metal precursor, etc. are coordinated with each other and cooperate to form a complete Only in this way can the selenium/tellurium doped copper-nickel-based nanowire catalyst required by the present invention be prepared.

Apparently, the above-mentioned embodiments of the present invention are only examples for clearly illustrating the present invention, rather than limiting the implementation of the present invention. For those of ordinary skill in the art, other changes or changes in different forms can be made on the basis of the above description. All the implementation manners cannot be exhaustively listed here. All obvious changes or variations derived from the technical solutions of the present invention are still within the protection scope of the present invention.

Claims (10)

1. a preparation method of selenium/tellurium-doped copper-nickel-based nanowire catalyst, is characterized in that, comprises the steps: 1) Put the copper precursor, the nickel precursor and the surfactant in an organic solvent, stir in an inert gas atmosphere and at a suitable temperature until the solution is evenly mixed; 2) keep stirring, the temperature is raised to the first reaction temperature and heated for a period of time; 3) The solution is continuously stirred, and the temperature is raised to the second reaction temperature again and heated for a period of time; 4) Take a certain amount of selenium/tellurium powder and dissolve it in oleylamine, and disperse it ultrasonically to obtain a selenium/tellurium powder solution for subsequent use; 5) After the reactor cools down, add the selenium/tellurium powder solution, keep stirring under an inert atmosphere and heat up to the third reaction temperature again and heat for a period of time; 6) After the reactor is cooled, the product is washed several times, then centrifuged, and vacuum-dried to obtain a selenium/tellurium-doped copper-nickel nanowire catalyst. 2. preparation method according to claim 1, is characterized in that: in step 1), the precursor of described copper is copper acetylacetonate, and the precursor of described nickel is nickel chloride hexahydrate, and described tensio-active agent It is dimethyl dioctadecyl ammonium chloride; the molar ratio of the copper precursor, the nickel precursor and the surfactant is 1-2:1:1-1.5; Preferably, in step 1), the organic solvent is oleylamine, and the ratio of the amount of the copper precursor to the organic solvent is 0.8mmol/8-10mL. 3. The preparation method according to claim 1, characterized in that: in step 1), the inert gas is nitrogen or argon; Preferably, in step 1), the appropriate temperature is 60-90°C, and the stirring time is 30-90min. 4. The preparation method according to claim 1, characterized in that: in step 2), the first reaction temperature is 170-190°C, and the period of time is 200-300min. 5. The preparation method according to claim 1, characterized in that: in step 3), the second reaction temperature is 200-250°C, and the period of time is 60-100min. 6. The preparation method according to claim 1, characterized in that: in step 4), the mass concentration of the selenium/tellurium powder solution is 2-5g/L; Preferably, in step 4), the conditions for the ultrasonic dispersion are: 1-5 minutes of ultrasonication at 40%-80% of 400W power. 7. The preparation method according to claim 1, characterized in that: in step 5), the temperature is lowered to 30-70°C, the third reaction temperature is 70-110°C, and the period of time is 60-90min ; Preferably, in step 5), the inert atmosphere is nitrogen or argon. 8. The preparation method according to claim 1, characterized in that: in step 6), the washing solvent is ethanol or n-hexane. 9. The preparation method according to claim 1, characterized in that: in step 6), the centrifuging speed is 5000-9000r, and the time is 5-10min. 10. The preparation method according to claim 1, characterized in that: in step 6), the vacuum drying temperature is 40-110°C, and the time is 8-24h; Preferably, in step 6), the vacuum degree of the vacuum drying is 0.08-0.1 MPa.

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