Trinickel disulfide / sulfur-nitrogen co-doped carbon nanocomposite catalytic material and preparation method thereof

Abstract

The application discloses a kind of trinickel disulfide / sulfur-nitrogen co-doped carbon nano composite catalytic materials and preparation method, it is related to the preparation technical field of nanocomposite.The method includes: raw material nickel nitrate, sodium chloride, 1,3,5-triazine alkane-2,4,6-trithione and water are uniformly mixed in reactor;The obtained mixed solution is heated to reflux state, and heat preservation for a period of time, the obtained suspension is spray dried, to prevent sodium chloride as template agent from precipitating, to obtain dry dark brown powder;The obtained dark brown powder is placed in pyrolysis furnace, control temperature is 1000~1100 ℃, pyrolysis 3~5h under the condition of flowing hydrogen argon mixed gas atmosphere, after washing with water and drying, it is obtained.The method of the application exposes more active sites by reducing aggregation, and reduces the use of organic solvent in the preparation process.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of preparation of nanocomposites, in particular to a kind of trinickel disulfide / sulfur-nitrogen co-doped carbon nanocomposite catalytic material and preparation method. BACKGROUND

[0002] Compared with traditional catalysts, nanocatalysts have the advantages of large surface area, good stability and high activity, but the aggregation problem caused by thermodynamic instability still exists, and aggregation will greatly reduce the catalytic performance of nanocatalysts due to a large number of unexposed active sites. Therefore, it is necessary to disperse the nanocatalysts during preparation.

[0003] Application No. 201711228648.4 discloses a preparation method of high-dispersion nanocatalyst, comprising: (1) preparing metal salt solution and precipitant solution respectively, continuously dropping the metal salt solution into the precipitant solution under continuous stirring, continuing to stir, and then carrying out first low-temperature hydrothermal reaction; the obtained product is filtered, washed, dried, and then subjected to second low-temperature hydrothermal reaction, and then filtered and vacuum dried to obtain metal oxide carrier rich in oxygen vacancy sites; (2) loading noble metal on the prepared metal oxide carrier by impregnation method, and obtaining high-dispersion nanocatalyst by temperature programmed reduction under hydrogen atmosphere.

[0004] Application No. 201511020351.X discloses a preparation method of high-dispersion supported metal nanocatalyst, which comprises the following steps: first, adding activated porous carrier into polyacrylic acid solution by excess impregnation method, filtering, and drying the solid to obtain polyacrylic acid modified carrier; then, impregnating the polyacrylic acid modified carrier into metal precursor solution by equal-volume impregnation method, drying, and calcining to obtain supported metal nanocatalyst.

[0005] In the above preparation methods of high-dispersion nanocatalyst, impregnation method is used to prepare nanocatalyst in order to improve the dispersity of nanocatalyst, but the dispersity of nanocatalyst still needs to be further improved. SUMMARY

[0006] One of the purposes of the present application is to provide a preparation method of trinickel disulfide / sulfur-nitrogen co-doped carbon nanocomposite catalytic material, which exposes more active sites by reducing aggregation, and reduces the use of organic solvents in the preparation process.

[0007] In order to achieve the above purpose, the present application adopts the following technical solutions:

[0008] A preparation method of trinickel disulfide / sulfur-nitrogen co-doped carbon nanocomposite catalytic material, which is prepared by one-step sulfidation process, the preparation method comprises:

[0009] Step one, the raw material nickel nitrate, sodium chloride, 1,3,5-triazine alkane-2,4,6-trithione and water are mixed uniformly in a reactor;

[0010] Step two, the mixed solution obtained in step one is heated to reflux state and kept for a period of time, and the obtained suspension is spray dried to prevent sodium chloride as a template from precipitating, to obtain a dry dark brown powder;

[0011] Step three, the dark brown powder is placed in a pyrolysis furnace, the temperature is controlled at 1000-1100℃, and pyrolysis is carried out under the condition of flowing hydrogen-argon mixed gas for 3-5h, and after washing with water and drying, it is obtained.

[0012] As a preferred embodiment of the present application, in step one: sodium chloride is used as a template, and 1,3,5-triazine alkane-2,4,6-trithione is used as a sulfur source, a carbon source and a nitrogen source.

[0013] As another preferred embodiment of the present application, in step one: a stirrer is arranged in the reactor, and stirring is carried out for 200-400min to mix uniformly.

[0014] The preparation method of the above-mentioned trinickel disulfide / sulfur-nitrogen co-doped carbon nanocomposite catalytic material, in step three: the heating rate of the pyrolysis process is controlled at 1℃ / min.

[0015] The preparation method of the above-mentioned trinickel disulfide / sulfur-nitrogen co-doped carbon nanocomposite catalytic material, in step one, the mass ratio of each raw material is: 1-3:0.5-1.5:9-11:2-4.

[0016] The preparation method of the above-mentioned trinickel disulfide / sulfur-nitrogen co-doped carbon nanocomposite catalytic material, in step one, the mass ratio of each raw material is: 2:1:10:3.

[0017] Another object of the present application is to provide a trinickel disulfide / sulfur-nitrogen co-doped carbon nanocomposite catalytic material prepared by the above-mentioned preparation method, which is a black powder.

[0018] Compared with the prior art, the present application has the following beneficial technical effects:

[0019] (1) In the selection of raw materials, nickel nitrate, sodium chloride, 1,3,5-triazine alkane-2,4,6-trithione and water are selected, and the raw material nickel nitrate, compared with the commonly used raw materials in the prior art, has moderate price and abundant reserves, which can further save production cost.

[0020] (2) In the preparation method, the two-nickel disulfide / sulfur-nitrogen co-doped carbon nanocomposite catalytic material is prepared by one-step method, avoiding the secondary sulfidation method in the prior art. In the preparation method, the spray drying of the suspension liquid can prevent the precipitation of the template agent. Through high-temperature pyrolysis, sodium chloride forms a molten salt template at high temperature, which is helpful for the product morphology construction and the generation of pure-phase two-nickel disulfide.

[0021] Preparation principle: The present application utilizes the coordination of sulfur-nitrogen-containing organic matter and transition metal salt to prepare a precursor, and under the action of a sodium chloride template (which can form a molten salt template at high temperature), a two-nickel disulfide / sulfur-nitrogen co-doped carbon nanocomposite catalytic material with high specific surface area and high active site exposure rate is obtained. 1,3,5-triazine alkane-2,4,6-trithione serves as a sulfur source, a carbon source and a nitrogen source; the sodium chloride template can not only increase the specific surface area and active site exposure rate of the nanocomposite catalyst, but also effectively inhibit the decomposition of metal sulfides.

[0022] (3) The two-nickel disulfide / sulfur-nitrogen co-doped carbon nanocomposite catalytic material provided by the present application can not only improve the dispersion of the catalyst, but also effectively reduce energy consumption, and one-step method saves operation steps compared with the traditional two-step method. BRIEF DESCRIPTION OF DRAWINGS

[0023] The present application will be further described below in conjunction with the drawings:

[0024] Figure 1 The X-ray diffraction pattern of the two-nickel disulfide / sulfur-nitrogen co-doped carbon nanocomposite catalytic material prepared by the present application is shown in the figure;

[0025] In the figure, (101), (110), (003), (202), (113), (211), and (122) represent the crystal plane indices of the crystal;

[0026] Figure 2 Figures (a) and (b) respectively show the scanning electron microscope and transmission electron microscope images of the two-nickel disulfide / sulfur-nitrogen co-doped carbon nanocomposite catalytic material with different particle sizes. DETAILED DESCRIPTION

[0027] The present application proposes a two-nickel disulfide / sulfur-nitrogen co-doped carbon nanocomposite catalytic material and a preparation method. In order to make the advantages and technical solutions of the present application more clear and explicit, the present application will be further described below in conjunction with specific examples.

[0028] The raw materials described in the present application can be obtained by commercial channels.

[0029] The application discloses a preparation method of a trinickel disulfide / sulfur-nitrogen co-doped carbon nanocomposite catalytic material.

[0030] In the application, sodium chloride is used as a template agent, 1,3,5-triazinane-2,4,6-trithione is used as a sulfur source, a carbon source and a nitrogen source at the same time, and a precursor is prepared through coordination of 1,3,5-triazinane-2,4,6-trithione and nickel nitrate; and the trinickel disulfide / sulfur-nitrogen co-doped carbon nanocomposite catalytic material with high specific surface area and high active site exposure rate is prepared under the action of the sodium chloride template.

[0031] The specific preparation method is as follows:

[0032] In step one, the raw materials, namely, nickel nitrate, sodium chloride, 1,3,5-triazinane-2,4,6-trithione and water, are uniformly mixed in a reactor; the mixture is stirred for 200-400 minutes by a stirrer arranged in the reactor, and the mass ratio of the raw materials is 1-3:0.5-1.5:9-11:2-4 in sequence; sodium chloride is used as a template agent, 1,3,5-triazinane-2,4,6-trithione is used as a sulfur source, a carbon source and a nitrogen source at the same time, and a precursor is prepared through coordination of 1,3,5-triazinane-2,4,6-trithione and nickel nitrate.

[0033] In step two, the mixed solution obtained in step one is heated to a reflux state and kept for a period of time, and the obtained suspension is subjected to spray drying, so as to prevent sodium chloride as a template agent from being precipitated, and a dry dark brown powder is obtained.

[0034] In step three, the dark brown powder is placed in a pyrolysis furnace, the temperature is controlled to be 1000-1100 DEG C, the temperature rising rate of the pyrolysis process is controlled to be 1 DEG C / min, the pyrolysis is performed under a flowing hydrogen-argon mixed gas atmosphere for 3-5 hours, and then the product is washed with water and dried.

[0035] The application will be further described below in combination with specific examples.

[0036] Example 1

[0037] The application discloses a preparation method of a trinickel disulfide / sulfur-nitrogen co-doped carbon nanocomposite catalytic material.

[0038] The nickel nitrate, the 1,3,5-triazinane-2,4,6-trithione, the sodium chloride and the water are fully mixed by stirring for 300 minutes in a three-necked flask, and the mass ratio of the nickel nitrate, the 1,3,5-triazinane-2,4,6-trithione, the sodium chloride and the water is 1:0.5:9:2.

[0039] The resulting mixture was heated to reflux and held at that temperature for 300 minutes. The suspension was then spray-dried to obtain a dried dark brown powder. The powder was then pyrolyzed at 1000°C under a flowing hydrogen-argon mixed atmosphere for 3 hours at a heating rate of 1°C / min. -1 The black powder obtained after washing and drying is a nickel disulfide / sulfur-nitrogen co-doped carbon nanocomposite catalytic material.

[0040] Example 2:

[0041] Preparation method of nickel disulfide / sulfur-nitrogen co-doped carbon nanocomposite catalytic material:

[0042] Nickel nitrate, 1,3,5-triazine-2,4,6-trithione, sodium chloride and water were stirred in a three-necked flask for 400 minutes to mix thoroughly. The mass ratio of nickel nitrate, 1,3,5-triazine-2,4,6-trithione, sodium chloride and water was 2:1:10:3.

[0043] The resulting mixture was heated to reflux and held at that temperature for 300 minutes. The suspension was then spray-dried to obtain a dried dark brown powder. The powder was then pyrolyzed at 1050 °C under a flowing hydrogen-argon mixed atmosphere for 4 hours at a heating rate of 1 °C / min. -1 The black powder obtained after washing and drying is a nickel disulfide / sulfur-nitrogen co-doped carbon nanocomposite catalytic material.

[0044] The X-ray diffraction pattern of the carbon nanocomposite catalytic material prepared in this embodiment is as follows: Figure 1 As shown, the scanning electron microscope image is as follows: Figure 2 As shown in (a) and (b).

[0045] Example 3:

[0046] Preparation method of nickel disulfide / sulfur-nitrogen co-doped carbon nanocomposite catalytic material:

[0047] Nickel nitrate, 1,3,5-triazine-2,4,6-trithione, sodium chloride, and water were stirred in a three-necked flask for 200 minutes to mix thoroughly. The mass ratio of nickel nitrate, 1,3,5-triazine-2,4,6-trithione, sodium chloride, and water was 3:1.5:11:4.

[0048] The resulting solution was heated to reflux and held at that temperature for 300 minutes. The suspension was then spray-dried to obtain a dried dark brown powder. The powder was then pyrolyzed at 1050 °C for 5 hours under a flowing hydrogen-argon mixed atmosphere, with a heating rate of 1 °C / min. -1 The black powder obtained after washing and drying is a nickel disulfide / sulfur-nitrogen co-doped carbon nanocomposite catalytic material.

[0049] Comparative Example 1:

[0050] Preparation method of trinickel disulfide / sulfur-nitrogen co-doped carbon nanocomposite catalytic material:

[0051] The nickel nitrate, 1, 3, 5-triazine-2, 4, 6-trithione, potassium chloride and water are stirred in a three-necked flask for 400 minutes to be fully mixed, wherein the mass ratio of the nickel nitrate, 1, 3, 5-triazine-2, 4, 6-trithione, ethylenediamine and water is 2:1:10:3; wherein the ethylenediamine is used as a template agent;

[0052] The mixed solution is heated to a reflux state and kept for 300 minutes, and the suspension is spray dried to obtain a dried dark brown powder. The dark brown powder is pyrolyzed at 1050 DEG C under a flowing hydrogen-argon mixed gas atmosphere for 4 hours, and the temperature rising rate is 1 DEG C / min -1 After water washing and drying, the black powder is a trinickel disulfide / sulfur-nitrogen co-doped carbon nanocomposite catalytic material.

[0053] Comparative Example 2:

[0054] Preparation method of trinickel disulfide / sulfur-nitrogen co-doped carbon nanocomposite catalytic material:

[0055] The nickel nitrate, 1, 3, 5-triazine-2, 4, 6-trithione, potassium chloride and water are stirred in a three-necked flask for 400 minutes to be fully mixed, wherein the mass ratio of the nickel nitrate, 1, 3, 5-triazine-2, 4, 6-trithione, ethylenediamine and water is 2:1:10:3; wherein the ethylenediamine is used as a template agent;

[0056] The mixed solution is heated to a reflux state and kept for 300 minutes, and the suspension is spray dried to obtain a dried dark brown powder. The dark brown powder is pyrolyzed at 1050 DEG C under a flowing hydrogen-argon mixed gas atmosphere for 4 hours, and the temperature rising rate is 1 DEG C / min -1 After water washing and drying, the black powder is a trinickel disulfide / sulfur-nitrogen co-doped carbon nanocomposite catalytic material.

[0057] The carbon nanocomposite materials prepared by the above-mentioned Example 1, Example 2, Example 3, Comparative Example 1 and Comparative Example 2 are detected, and the detection data are shown in Table 1.

[0058] Table 1

[0059]

[0060] The parts not mentioned in the present application can be realized by referring to the prior art.

[0061] It should be noted that any equivalent ways or obvious modifications made by those skilled in the art under the guidance of the present application should be within the protection scope of the present application.

Claims

1. A method for preparing a trinickel disulfide / sulfur-nitrogen co-doped carbon nanocomposite catalytic material, characterized in that, It is prepared by one-step vulcanization process, and the preparation method comprises the following steps: Step one, uniformly mix raw materials nickel nitrate, sodium chloride, 1,3,5-triazine alkane-2,4,6-trithione and water in a reactor; Step two, heat the mixed solution obtained in step one to reflux state and keep warm for a period of time, and spray dry the obtained suspension to prevent sodium chloride as a template from precipitating, to obtain dry dark brown powder; Step three, place the dark brown powder in a pyrolysis furnace, control the temperature to be 1000-1100℃, pyrolyze under the condition of flowing hydrogen and argon mixed gas for 3-5h, and then wash with water and dry to obtain the product; In step one, sodium chloride is used as a template, and 1,3,5-triazine alkane-2,4,6-trithione is used as a sulfur source, a carbon source and a nitrogen source; In step one, the mass ratio of each raw material is 1-3:0.5-1.5:9-11:2-4.

2. The preparation method of the trinickel disulfide / sulfur-nitrogen co-doped carbon nanocomposite catalytic material according to claim 1, characterized in that, In step one, a stirrer is arranged in the reactor, and stirring is performed for 200-400min to mix uniformly.

3. The preparation method of the trinickel disulfide / sulfur-nitrogen co-doped carbon nanocomposite catalytic material according to claim 1, characterized in that, In step three, the heating rate of the pyrolysis process is controlled to be 1℃ / min.

4. The preparation method of the trinickel disulfide / sulfur-nitrogen co-doped carbon nanocomposite catalytic material according to claim 1, characterized in that, In step one, the mass ratio of each raw material is 2:1:10:

3.

5. A trinickel disulfide / sulfur-nitrogen co-doped carbon nanocomposite catalytic material, characterized in that, It is prepared by the preparation method of the two nickel disulfide / sulfur-nitrogen co-doped carbon nanocomposite catalytic material according to any one of claims 1-4, and the two nickel disulfide / sulfur-nitrogen co-doped carbon nanocomposite catalytic material is black powder.

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