阅读说明：本技术 一种一维钴硫化合物/硫化亚铜复合物纳米阵列@泡沫铜材料及其制备方法和应用 (One-dimensional cobalt-sulfur compound/cuprous sulfide compound nano-array @ foamy copper material and preparation method and application thereof ) 是由 王伟智 李慰 但德鑫 吴俊瑶 于 2019-10-10 设计创作，主要内容包括：本发明提供了一种一维钴硫化合物/硫化亚铜复合物纳米阵列@泡沫铜材料及其制备方法和应用,将尿素与可溶性钴盐溶解在水中,恒温加热反应后可在泡沫铜基底上生长出一维阵列结构的Co前驱体材料。再将其置于N,N-二甲基甲酰胺溶剂中与巯基乙酸反应,得到一维Co<Sub>9</Sub>S<Sub>8</Sub>/Cu<Sub>2</Sub>S复合物纳米阵列@泡沫铜材料。与现有的技术相比,本发明通过液相方法制备出一维Co<Sub>9</Sub>S<Sub>8</Sub>/Cu<Sub>2</Sub>S复合物纳米阵列@泡沫铜材料,操作方便,设备和工艺简单,受环境影响小,易于大规模的生产；所得的一维Co<Sub>9</Sub>S<Sub>8</Sub>/Cu<Sub>2</Sub>S复合物纳米阵列@泡沫铜材料在酸性和碱性环境中都表现出优良的催化电解水析氢反应性能,具有良好的实际应用前景。(The invention provides a one-dimensional cobalt-sulfur compound/cuprous sulfide compound nano-array @ foamy copper material and a preparation method and application thereof. Then placing the mixture into an N, N-dimethylformamide solvent to react with thioglycollic acid to obtain one-dimensional Co 9 S 8 /Cu 2 S composite nano-array @ foam copper material. Compared with the prior art, the one-dimensional Co is prepared by a liquid phase method 9 S 8 /Cu 2 The S composite nano array @ foamed copper material is convenient to operate, simple in equipment and process, small in environmental influence and easy for large-scale production; the obtained one-dimensional Co 9 S 8 /Cu 2 The S composite nano array @ foamy copper material shows excellent catalytic electrolysis water hydrogen evolution reaction performance in both acidic and alkaline environments, and has good practical application prospect.)

1. A preparation method of a one-dimensional cobalt sulfide compound/cuprous sulfide compound nano array @ foamy copper material is characterized by comprising the following steps of:

A. placing foamy copper in a solution containing a cobalt source and urea, sealing, and heating for reaction to obtain a Co precursor @ foamy copper material;

B. and D, uniformly mixing thioglycollic acid and N, N-dimethylformamide, adding the Co precursor @ foamed copper material obtained in the step A, sealing, and carrying out heating reaction to obtain the one-dimensional cobalt sulfur compound/cuprous sulfide compound nano array @ foamed copper material.

2. The method according to claim 1, wherein Co is selected from the cobalt source in step A²⁺The molar ratio of the urea to the urea is 1: 2-1: 5.

3. The process according to claim 1 or 2, wherein in step a the cobalt source is selected from soluble cobalt salts with or without water of crystallization.

4. The method of claim 1, wherein the cobalt source in step a is selected from cobalt chloride hexahydrate, cobalt nitrate hexahydrate, or cobalt acetate.

5. The process according to claim 1, wherein in the solution containing cobalt source and urea in step A, Co is present²⁺The concentration of (A) is 0.075-0.2 mol/L.

6. The method according to claim 1, wherein the heating reaction conditions in step a are as follows: heating and reacting for 5-8 h at a constant temperature of 100-160 ℃.

7. The method according to claim 1 or 2, wherein the ratio by volume of thioglycolic acid to N, N-dimethylformamide in step B is: 1: 400-1: 600.

8. the production method according to claim 1 or 2, wherein the conditions of the heating reaction in step B are: heating and reacting for 10-14 h at a constant temperature of 180-220 ℃.

9. A one-dimensional cobalt sulfide/cuprous sulfide composite nanoarray @ copper foam material prepared by the preparation method of any one of claims 1-8.

10. The application of the one-dimensional cobalt sulfide compound/cuprous sulfide compound nano array @ copper foam material prepared by the preparation method of any one of claims 1-8 is characterized by being used as a catalyst for electrolytic water hydrogen evolution reaction.

Technical Field

The invention belongs to the field of material preparation, and particularly relates to a one-dimensional cobalt-sulfur compound/cuprous sulfide compound nano-array @ foam copper material, and a preparation method and application thereof.

Background

Since the last century, energy and environmental issues have become global focus issues. With the tremendous changes in the production and living of mankind brought about by the industrial revolution, energy consumption has increased and the storage of fossil fuels that have been explored has become less and less. And the use of a large amount of fossil fuels brings about countless environmental problems, such as global greenhouse effect, soil acid-base balance imbalance, atmospheric pollution and the like, and destroys the natural environment on which human beings depend to live. Therefore, developing a new energy source with abundant and clean reserves is a problem to be solved by global scientists.

Hydrogen is one of the best new energy sources for replacing fossil fuels due to the advantages of high combustion value, wide sources, zero carbon emission after combustion and the like. In order to popularize hydrogen as an energy source in daily life of people on a large scale, the development of a large-scale hydrogen production process is one of the key problems to be solved.

The hydrogen is prepared based on the hydrogen evolution reaction generated by the cathode of the electrolyzed water, and the advantages of no pollution, high product purity and high yield are obtained in a plurality of hydrogen preparation methods. However, the biggest difficulty in hydrogen production by water electrolysis is that the applied voltage is too high due to the over-potential of hydrogen evolution reaction, so that the loss of electric energy is increased, and the preparation cost of hydrogen is increased. The use of a catalyst to reduce the overpotential of the hydrogen evolution reaction is an effective way to solve this problem. However, hydrogen evolution reaction catalysts represented by noble metals such as Pt and Ir are limited in their large-scale application in practical industrial production because of their rare earth reserves and high price.

The research in recent years shows that the transition metal sulfide material has the performance of catalyzing hydrogen evolution reaction, is low in price and abundant in earth reserves, and is an ideal catalyst material for large-scale practical application of the water electrolysis hydrogen production process. However, the catalytic activity of the bulk transition metal sulfide is poor due to the small catalytic activity area, and the catalytic performance of the transition metal sulfide with a single component is much higher, so that the practical use effect is limited.

Disclosure of Invention

The invention aims to provide a one-dimensional cobalt sulfur compound/cuprous sulfide compound nano array @ copper foam material, wherein the one-dimensional nano array structure effectively improves the specific surface area of the material and increases the catalytic activity site of the material, and the cobalt sulfur compound and cuprous sulfide are compounded and have synergistic effect, so that the catalytic performance of the material is further improved.

The invention also aims to provide a preparation method of the one-dimensional cobalt sulfide/cuprous sulfide compound nano-array @ foamy copper material, which has the advantages of simple and efficient process, process and equipment and low raw material cost.

The invention also aims to provide an application of the one-dimensional cobalt sulfur compound/cuprous sulfide compound nano array @ foam copper material, which specifically comprises the following steps: application of catalyzing electrolysis water hydrogen evolution reaction. The one-dimensional cobalt sulfur compound/cuprous sulfide compound nano array @ foamy copper material provided by the invention is directly used as an electrode material for catalyzing the electrolysis water hydrogen evolution reaction, and shows excellent catalytic performance in both acidic and alkaline environments.

The specific technical scheme of the invention is as follows:

a preparation method of a one-dimensional cobalt sulfide compound/cuprous sulfide compound nano array @ foam copper material comprises the following steps:

A. placing foamy copper in a solution containing a cobalt source and urea, sealing, and heating for reaction to obtain a Co precursor @ foamy copper material;

B. and D, uniformly mixing thioglycollic acid and N, N-dimethylformamide, adding the Co precursor @ foamed copper material obtained in the step A, sealing, and carrying out heating reaction to obtain the one-dimensional cobalt sulfur compound/cuprous sulfide compound nano array @ foamed copper material.

Co in the cobalt source in the step A²⁺The molar ratio of the urea to the urea is 1: 2-1: 5.

In step A, the cobalt source is selected from soluble cobalt salts containing or not containing crystal water.

Preferably, the cobalt source in step a is selected from cobalt chloride hexahydrate, cobalt nitrate hexahydrate or cobalt acetate.

In the solution containing cobalt source and urea in step A, Co²⁺The concentration of (A) is 0.075-0.2 mol/L.

Further, the heating reaction conditions in the step A are as follows: heating and reacting for 5-8 h at a constant temperature of 100-160 ℃.

Preferably, step a specifically comprises:

adding a cobalt source and urea into deionized water, stirring until the cobalt source and the urea are completely dissolved, transferring the solution into a reaction kettle, adding foamy copper, sealing the reaction kettle, and heating for reaction.

And (C) after the heating reaction in the step A is finished, taking out the foamy copper, washing and drying.

The washing specifically comprises the following steps: washed with ethanol and deionized water, respectively.

The drying specifically comprises the following steps: drying in a vacuum drying oven at 65 deg.C for 5 hr,

and D, the product Co precursor @ foamy copper material obtained in the step A is a solid one-dimensional nano material with the diameter of 150-250 nm, and a one-dimensional nano structure array material is formed on the surface of the foamy copper.

The volume ratio of the thioglycolic acid to the N, N-dimethylformamide in the step B is as follows: 1: 400-1: 600.

further, the heating reaction conditions in the step B are as follows: heating and reacting for 10-14 h at a constant temperature of 180-220 ℃.

And D, after the heating reaction in the step B is finished, cooling to room temperature, taking out the foam copper, washing and drying.

The washing refers to washing with deionized water and ethanol for 3-5 times respectively.

The drying refers to drying for 6 hours in a vacuum drying oven at the temperature of 80 ℃.

The one-dimensional cobalt-sulfur compound/cuprous sulfide compound nano array @ foamy copper material provided by the invention is prepared by the method, and Co is formed on the surface of foamy copper₉S₈And Cu₂S-composed of a complex, Co₉S₈/Cu₂The S compound is a one-dimensional nanostructure, the diameter of the S compound is 150-300 nm, and the Co of the one-dimensional nanostructure₉S₈/Cu₂The S compound forms a nano array on the surface of the foam copper.

The invention also provides application of the one-dimensional cobalt sulfur compound/cuprous sulfide compound nano array @ foam copper material as a catalyst for the hydrogen evolution reaction by electrolysis water.

One-dimensional Co prepared by the invention₉S₈/Cu₂The S composite nano array @ foamy copper material can be directly used as an electrode and can be used for catalyzing the electrolysis water hydrogen evolution reaction in acidic and alkaline environments. The electrolytic water hydrogen evolution reaction is carried out at room temperature by using a standard three-electrode system. Prepared one-dimensional Co₉S₈/Cu₂The S compound nano array @ foamy copper material is used as a working electrode, a carbon rod is used as a counter electrode, a saturated Ag/AgCl electrode is used as a reference electrode, and the electrolyte is 0.5M H₂SO₄The solution and a 1M KOH solution were subjected to a Linear Sweep Voltammetry (LSV) test at a sweep rate of 5 mV/s.

In the invention, urea and soluble cobalt salt are dissolved in water, and under the condition of constant-temperature heating reaction, the urea is hydrolyzed to generate NH₃And CO₂Then NH₃And CO₂React with water to form OH^-And CO₃ ^2-. In solution, OH^-And CO₃ ^2-With Co supplied by soluble cobalt salts²⁺And reacting to generate basic cobalt carbonate on the surface of the foam copper. With the extension of the reaction time, the basic cobaltous carbonate gradually grows to form a one-dimensional nano structure, so that the Co precursor material with the one-dimensional array structure is formed on the foam copper substrate. It was further reacted with thioglycolic acid in N, N-dimethylformamide solvent. N, N-dimethylformamide as a solvent is alkaline, and thioglycolic acid can slowly release S in the environment^2-Sulfurizing with Co precursor to produce Co₉S₈. Because of S^2-Slowly released, and the sulfurization reaction firstly occurs on the surface of the Co precursor, so that the original one-dimensional nano-array structure of the Co precursor is maintained. At the same time, the copper foam used as the substrate in the reaction is in alkaliUnder the environment of nature, the surface can be oxidized to slowly release Cu⁺With S in solution^2-Cu generated by reaction₂S, and sulfurizing with one-dimensional Co precursor to obtain Co₉S₈Combine to obtain Cu₂S and Co₉S₈The composite product of (1). Due to Cu₂Very small solubility product of S, Cu⁺Is very easy to react with S^2-By reactions, e.g. with easy release of S^2-In place of thioglycolic acid, substances such as sodium sulfide, thiourea, etc., a large amount of free S^2-But also Cu released from the foam copper rapidly⁺Reaction to produce Cu₂Large particles of S or CuS precipitate. If soluble copper salt containing copper ions such as copper chloride and copper nitrate is directly added into the reaction system, the copper ions in the solution can be rapidly reacted with S^2-The reaction is carried out, and a large amount of CuS particle precipitates are directly generated. So that one-dimensional Co with uniform structure and composition cannot be obtained₉S₈/Cu₂S composite nano array structures.

Co prepared by the invention₉S₈/Cu₂The S compound is a one-dimensional nano structure consisting of particles, and the surface is rough, so that more catalytic active sites can be exposed. One-dimensional Co₉S₈/Cu₂The S composite nano material forms an array structure on the surface of the foam copper, the foam copper is a substrate with good conductivity, so that the material can be directly used as an electrode for catalyzing the electrolysis water hydrogen evolution reaction, the electron transmission rate of the electrode material in the catalysis process can be increased, and the catalysis hydrogen evolution reaction is facilitated. And the nano array structure can increase the contact area of the material and the electrolyte and further improve the catalytic performance of the material. In addition, the foamy copper is a base resistant to acid and alkali, the cobalt-sulfur compound and the cuprous sulfide are compounded, and the one-dimensional Co prepared by the invention is enabled to be used as a substrate through the synergistic effect of the two substances₉S₈/Cu₂The S composite nano array @ foam copper material shows excellent catalytic hydrogen evolution reaction performance in both acidic and alkaline environments. The test results show that compared with the Cu formed by direct vulcanization of the foam copper, the Cu is formed by direct vulcanization₂S @ foamy copper material and pure foamy copper material, and one-dimensional Co prepared by the invention₉S₈/Cu₂The catalytic hydrogen evolution reaction performance of the S composite nano array @ foam copper material in acidic and alkaline environments is remarkably improved.

Compared with the prior art, the one-dimensional Co is prepared by a liquid phase method₉S₈/Cu₂The S composite nano array @ foamed copper material is convenient to operate, simple in equipment and process, small in environmental influence and easy for large-scale production; the obtained one-dimensional Co₉S₈/Cu₂The S composite nano array @ foamy copper material shows excellent catalytic electrolysis water hydrogen evolution reaction performance in both acidic and alkaline environments, and has good practical application prospect.

Drawings

The following describes embodiments of the present invention in further detail with reference to the accompanying drawings.

FIG. 1 is a scanning electron microscope image of the Co precursor @ foamy copper material obtained in example 1;

FIG. 2 is a transmission electron microscope image of a Co precursor sample peeled from the surface of copper foam obtained after the Co precursor @ copper foam material obtained in example 1 is subjected to ultrasonic processing;

FIG. 3 shows one-dimensional Co obtained in example 1₉S₈/Cu₂A scanning electron microscope image of the S composite nano array @ foamy copper material;

FIG. 4 shows one-dimensional Co obtained in example 1₉S₈/Cu₂An X-ray diffraction pattern of a sample stripped from the surface of the foamy copper is obtained after the S composite nano array @ foamy copper material is subjected to ultrasonic treatment;

FIG. 5 shows one-dimensional Co obtained in example 2₉S₈/Cu₂A transmission electron microscope image of a sample peeled from the surface of the foamy copper obtained after the S composite nano array @ foamy copper material is subjected to ultrasonic treatment;

FIG. 6 shows one-dimensional Co obtained in example 3₉S₈/Cu₂A scanning electron microscope image of the S composite nano array @ foamy copper material;

FIG. 7 shows one-dimensional Co obtained in example 4₉S₈/Cu₂A scanning electron microscope image of the S composite nano array @ foamy copper material;

FIG. 8 shows one-dimensional Co obtained in example 5₉S₈/Cu₂A scanning electron microscope image of the S composite nano array @ foamy copper material;

FIG. 9 shows one-dimensional Co obtained in example 6₉S₈/Cu₂A scanning electron microscope image of the S composite nano array @ foamy copper material;

FIG. 10 shows one-dimensional Co obtained in example 1₉S₈/Cu₂S composite nano array @ foam copper material, pure foam copper and Cu₂S @ foamy copper material is 0.5M H₂SO₄A comparison graph of polarization curves of catalytic hydrogen evolution reactions in solution;

FIG. 11 shows one-dimensional Co obtained in example 1₉S₈/Cu₂S composite nano array @ foam copper material, pure foam copper and Cu₂A comparison graph of polarization curves of S @ foamy copper material in a 1M KOH solution for catalytic hydrogen evolution reaction is shown.

Detailed Description

For the purpose of facilitating an understanding of the present invention, the present invention will now be described by way of examples. It should be understood by those skilled in the art that the examples are merely for the understanding of the present invention, and the specific description is illustrative and should not be construed as limiting the scope of the present invention. It will be appreciated by those skilled in the art that the present invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof, and it is therefore intended to cover all modifications within the scope of the invention or the equivalent thereof.