阅读说明：本技术 一种碳纳米管载钌钴析氢催化剂的制备方法 (Preparation method of carbon nano tube supported ruthenium-cobalt hydrogen evolution catalyst ) 是由 张卜升 赵盘巢 党蕊 郭俊秋 黄钰杰 于 2021-09-10 设计创作，主要内容包括：本发明公开了一种碳纳米管载钌钴析氢催化剂的制备方法,包括以下步骤：一、将碳纳米管与乙醇溶液加热搅拌,静置沉降去除上层清液；二、将碳纳米管与混合溶液加热搅拌,静置沉降后去除上层清液；三、将碳纳米管与乙二胺溶液加热搅拌,静置沉降后去除上层清液；四、将碳纳米管、钌盐、钴盐和去离子水超声搅拌；五、将混合液喷雾干燥；六、将复合粉末在氢氩混合气氛下加热；七、将前驱体粉末与乙醇溶液加热搅拌,静置沉降后去除上层清液,得到碳纳米管载钌钴析氢催化剂。本发明通过在碳纳米管表面负载羟基、羧基、氨基等多种官能团,提升了催化剂的应用性能,制备的碳纳米管载钌钴析氢催化剂中金属粒子平均粒径小于8nm,展现了优异的析氢性能。(The invention discloses a preparation method of a carbon nano tube supported ruthenium-cobalt hydrogen evolution catalyst, which comprises the following steps: firstly, heating and stirring carbon nano tubes and an ethanol solution, standing and settling to remove supernatant; heating and stirring the carbon nano tube and the mixed solution, standing and settling, and removing supernatant liquor; thirdly, heating and stirring the carbon nano tube and the ethylenediamine solution, standing and settling, and removing supernatant liquor; fourthly, ultrasonically stirring the carbon nano tube, the ruthenium salt, the cobalt salt and the deionized water; fifthly, spray drying the mixed solution; sixthly, heating the composite powder under the hydrogen-argon mixed atmosphere; and seventhly, heating and stirring the precursor powder and the ethanol solution, standing and settling, and removing the supernatant to obtain the ruthenium-cobalt-carried carbon nanotube hydrogen evolution catalyst. According to the invention, by loading various functional groups such as hydroxyl, carboxyl, amino and the like on the surface of the carbon nano tube, the application performance of the catalyst is improved, and the average particle size of metal particles in the prepared ruthenium-cobalt-loaded hydrogen evolution catalyst for the carbon nano tube is less than 8nm, so that the excellent hydrogen evolution performance is shown.)

1. A preparation method of a carbon nano tube supported ruthenium cobalt hydrogen evolution catalyst is characterized by comprising the following steps:

step one, placing the carbon nano tube in an ethanol solution, heating and stirring, then standing and settling, removing supernatant, and then cleaning with deionized water to obtain an ethanol-treated carbon nano tube;

step two, placing the ethanol-treated carbon nano tube obtained in the step one in a mixed solution, heating and stirring, then standing and settling, removing supernatant, and then cleaning with deionized water to neutrality to obtain a mixed solution-treated carbon nano tube; the mixed solution consists of a hydrogen peroxide solution and a dilute nitric acid solution;

step three, placing the mixed solution treated carbon nano tube obtained in the step two in an ethylenediamine solution, then heating and stirring, then standing and settling, removing supernatant liquor, and then cleaning with deionized water to obtain an ethylenediamine treated carbon nano tube;

step four, adding the ethylenediamine treated carbon nano tube, the ruthenium salt and the cobalt salt obtained in the step three into deionized water, and then sequentially carrying out ultrasonic treatment and stirring to obtain a mixed solution;

step five, carrying out spray drying on the mixed solution obtained in the step four to obtain composite powder;

step six, heating the composite powder obtained in the step five under a hydrogen-argon mixed atmosphere to obtain precursor powder;

and step seven, placing the precursor powder obtained in the step six in an ethanol solution, heating and stirring, then standing and settling, removing supernatant, cleaning with deionized water, and drying to obtain the carbon nano tube supported ruthenium-cobalt hydrogen evolution catalyst.

2. The method for preparing the catalyst for hydrogen evolution of ruthenium-cobalt carried on carbon nanotubes as claimed in claim 1, wherein the carbon nanotubes in the first step are multiwalled carbon nanotubes, the mass fraction of ethanol in the ethanol solution is 30-70%, the heating and stirring time is 4-10 h, and the temperature is 40-80 ℃.

3. The method for preparing the catalyst for hydrogen evolution with ruthenium and cobalt carried on carbon nanotubes as claimed in claim 1, wherein the concentration of hydrogen peroxide in the mixed solution in the second step is 1mol/L to 4mol/L, the concentration of nitric acid is 1mol/L to 3mol/L, the heating and stirring time is 4h to 10h, and the temperature is 40 ℃ to 80 ℃.

4. The method for preparing the catalyst for hydrogen evolution of cobalt ruthenium carried on carbon nano tube according to claim 1, wherein the concentration of ethylenediamine in the ethylenediamine solution in the step three is 0.5mol/L to 2mol/L, the heating and stirring time is 1h to 4h, and the temperature is 40 ℃ to 80 ℃.

5. The method for preparing the carbon nanotube-supported ruthenium-cobalt hydrogen evolution catalyst according to claim 1, wherein the ruthenium salt in the step four is ruthenium trichloride hydrate, the cobalt salt is cobalt chloride, cobalt sulfate or cobalt nitrate hydrate, the concentration of the carbon nanotube in the mixed solution is 0.1 g/L-1 g/L, and the mass ratio of the carbon nanotube to the metal ion is 3-20: 1, the atomic ratio of the ruthenium element to the cobalt element is 1-10: 1, the ultrasonic time is 30-60 min, and the stirring time is 12-72 h.

6. The method for preparing the carbon nanotube-supported ruthenium-cobalt hydrogen evolution catalyst according to claim 1, wherein the temperature of the spray drying in the step five is 150 ℃ to 250 ℃, and the flow rate of the mixed solution for spray drying is 100mL/h to 300 mL/h.

7. The method for preparing the carbon nanotube supported ruthenium cobalt hydrogen evolution catalyst according to claim 1, wherein the heating process in the sixth step is as follows: heating to 200-600 ℃ at the heating rate of 4-10 ℃/min, and then preserving the heat for 0.5-3 h.

8. The method for preparing the ruthenium-cobalt-supported carbon nanotube hydrogen evolution catalyst according to claim 1, wherein the volume fraction of hydrogen in the hydrogen-argon mixed atmosphere in the sixth step is 7% to 9%, and the balance is argon.

9. The method for preparing the carbon nanotube-supported ruthenium-cobalt hydrogen evolution catalyst according to claim 1, wherein the ethanol solution in the seventh step has a mass fraction of 30-70%, the heating and stirring time is 1-6 h, and the temperature is 40-80 ℃.

Technical Field

The invention belongs to the technical field of hydrogen evolution catalysts, and particularly relates to a preparation method of a carbon nano tube supported ruthenium-cobalt hydrogen evolution catalyst.

Background

The hydrogen has the characteristics of light weight, good thermal conductivity, high reserve, high heat value, wide utilization form, suitability for storage and transportation of various forms, cleanness and the like, is regarded as the clean energy with the most development potential in the 21 st century, and is the most ideal alternative energy for solving the problems of energy, environment and the like. The electrolysis of water is an important method for producing high-purity hydrogen, and is an important component of modern hydrogen energy technology.

The electrolysis of water consists of two half reactions of cathodic hydrogen evolution and anodic oxygen evolution, the hydrogen evolution reaction directly generates hydrogen, which is a key step of hydrogen production by water electrolysis, and in the prior art, noble metal Pt is mostly adopted as the cathode of the water electrolysis, so the cost is higher.

At present, the research on the hydrogen evolution reaction by exploring cheap metal or compound with excellent electrocatalysis performance to replace Pt is a key point, and the development of an oxygen evolution catalyst which is simple, convenient, controllable in components, good in performance and capable of being popularized in a large scale and a preparation method thereof are key points of a water electrolysis hydrogen production technology.

Disclosure of Invention

The technical problem to be solved by the present invention is to provide a method for preparing a carbon nanotube-supported ruthenium-cobalt hydrogen evolution catalyst, aiming at the defects of the prior art. According to the method, a plurality of functional groups such as hydroxyl, carboxyl, amino and the like are loaded on the surface of the carbon nano tube, so that the loading capacity of metal ions on the carbon nano tube is improved, ruthenium and cobalt are loaded on the surface of the carbon nano tube, then spray drying is carried out, heating and heat preservation are carried out under a hydrogen-argon mixed atmosphere, finally heating and stirring are carried out in an ethanol solution, the application performance of the ruthenium-loaded cobalt hydrogen evolution catalyst of the carbon nano tube is improved, the average particle size of metal particles in the prepared ruthenium-loaded cobalt hydrogen evolution catalyst of the carbon nano tube is smaller than 8nm, and excellent hydrogen evolution performance is shown in a 0.5M sulfuric acid solution and a 1M potassium hydroxide solution.

In order to solve the technical problems, the invention adopts the technical scheme that: a preparation method of a carbon nano tube supported ruthenium cobalt hydrogen evolution catalyst is characterized by comprising the following steps:

step one, placing the carbon nano tube in an ethanol solution, heating and stirring, then standing and settling, removing supernatant, and then cleaning with deionized water to obtain an ethanol-treated carbon nano tube;

step two, placing the ethanol-treated carbon nano tube obtained in the step one in a mixed solution, heating and stirring, then standing and settling, removing supernatant, and then cleaning with deionized water to neutrality to obtain a mixed solution-treated carbon nano tube; the mixed solution consists of a hydrogen peroxide solution and a dilute nitric acid solution;

step three, placing the mixed solution treated carbon nano tube obtained in the step two in an ethylenediamine solution, then heating and stirring, then standing and settling, removing supernatant liquor, and then cleaning with deionized water to obtain an ethylenediamine treated carbon nano tube;

step four, adding the ethylenediamine treated carbon nano tube, the ruthenium salt and the cobalt salt obtained in the step three into deionized water, and then sequentially carrying out ultrasonic treatment and stirring to obtain a mixed solution;

step five, carrying out spray drying on the mixed solution obtained in the step four to obtain composite powder;

step six, heating the composite powder obtained in the step five under a hydrogen-argon mixed atmosphere to obtain precursor powder;

and step seven, placing the precursor powder obtained in the step six in an ethanol solution, heating and stirring, then standing and settling, removing supernatant, cleaning with deionized water, and drying to obtain the carbon nano tube supported ruthenium-cobalt hydrogen evolution catalyst.

The invention sequentially puts carbon nano tubes into a mixed solution of ethanol, hydrogen peroxide and dilute nitric acid and an ethylenediamine solution for heating and stirring, respectively loads a plurality of functional groups such as hydroxyl, carboxyl, amino and the like on the surfaces of the carbon nano tubes, thereby improving the loading capacity of metal ions on the carbon nano tubes, simultaneously enhancing the wettability of the carbon nano tubes in an aqueous solution so as to finally obtain a hydrogen evolution catalyst with more uniform components, then adds the carbon nano tubes, ruthenium salt and cobalt salt loaded with the plurality of functional groups on the surfaces into deionized water, then sequentially carries out ultrasonic treatment and stirring, loads ruthenium and cobalt on the surfaces of the carbon nano tubes, then carries out spray drying on the mixed solution, realizes the uniform dispersion of the carbon nano tube ruthenium-loaded cobalt solution, thereby preparing carbon nano tube ruthenium-loaded cobalt powder with a micro-nano structure, and then heats the carbon nano tube metal-loaded particle powder in a hydrogen argon atmosphere, The heat preservation is carried out, the ruthenium-cobalt powder loaded on the carbon nano tube is reduced into a simple substance, the catalytic performance is improved, the catalyst is cleaned by heating and stirring in an ethanol solution, the wettability of the catalyst in an aqueous solution is improved by introducing hydroxyl, the application performance of the ruthenium-cobalt-loaded hydrogen evolution catalyst of the carbon nano tube is improved, ruthenium and cobalt in the prepared ruthenium-cobalt-loaded hydrogen evolution catalyst of the carbon nano tube have certain hydrogen evolution performance, and after the ruthenium element and the cobalt element are mixed, the synergistic effect between the elements is beneficial to the improvement of the catalytic performance, and the hydrogen evolution performance of the ruthenium-cobalt-loaded hydrogen evolution catalyst of the carbon nano tube is further improved.

The preparation method of the ruthenium-cobalt-supported carbon nanotube hydrogen evolution catalyst is characterized in that in the first step, the carbon nanotube is a multi-walled carbon nanotube, the mass fraction of ethanol in the ethanol solution is 30-70%, the heating and stirring time is 4-10 h, and the temperature is 40-80 ℃. The multi-walled carbon nanotube has good conductivity, and the multi-walled carbon nanotube is used as a carrier, so that the dispersibility of metal particles can be improved, agglomeration is prevented, and the stability of the catalyst is improved on the premise of not influencing the conductivity of the catalyst; the carbon nano tube is fully modified by controlling the mass fraction of the ethanol, the heating and stirring time and the temperature, so that functional groups such as hydroxyl groups and the like are fully loaded on the carbon nano tube, the highest reaction efficiency is ensured, the defects of strong volatility caused by overlarge mass fraction of the ethanol, large loss and unobvious modification effect caused by overlarge mass fraction are prevented, the defects of too short time, too few modification effect, too long time, most modification completion, unobvious effect in time increase are prevented, and the defects of too low temperature, long required time and too high temperature volatility are prevented.

The preparation method of the carbon nanotube-supported ruthenium-cobalt hydrogen evolution catalyst is characterized in that in the second step, the concentration of hydrogen peroxide in the mixed solution is 1-4 mol/L, the concentration of nitric acid is 1-3 mol/L, the heating and stirring time is 4-10 h, and the temperature is 40-80 ℃. The carbon nano tube is fully modified by controlling the concentration numbers of the hydrogen peroxide and the nitric acid, the time and the temperature of heating and stirring, functional groups such as carboxyl and the like are fully loaded on the carbon nano tube under the condition of not influencing the previous hydroxyl loading, the highest reaction efficiency is ensured, the defects of high modification effect caused by high concentration numbers of the hydrogen peroxide and the nitric acid, large loss and low mass fraction are prevented, the defects of too short time, too little modification effect, too long time, most of the modification is completed, the effect of increasing the time is not obvious are prevented, and the defects of too long time required by too low temperature and too high temperature volatility are prevented.

The preparation method of the carbon nanotube-supported ruthenium-cobalt hydrogen evolution catalyst is characterized in that the concentration of ethylenediamine in the ethylenediamine solution in the step three is 0.5-2 mol/L, the heating and stirring time is 1-4 h, and the temperature is 40-80 ℃. The carbon nano tube is fully modified by controlling the concentration of the ethylenediamine, the heating and stirring time and the temperature, functional groups such as amino groups and the like are fully loaded on the carbon nano tube under the condition that the hydroxyl and carboxyl are loaded before the carbon nano tube is not influenced, the highest reaction efficiency is ensured, the defects of strong volatility caused by overlarge concentration of the ethylenediamine, unobvious modification effect caused by large loss and undersize mass fraction are prevented, the defects of too short time, too few and unobvious modification effects, too long time, most of the modification is completed, and long time effect is increased are prevented, and the defects of longer time required by too low temperature and too high volatility of too high temperature are prevented.

The preparation method of the carbon nanotube-supported ruthenium-cobalt hydrogen evolution catalyst is characterized in that in the fourth step, the ruthenium salt is ruthenium trichloride hydrate, the cobalt salt is cobalt chloride, cobalt sulfate or cobalt nitrate hydrate, the concentration of the carbon nanotube in the mixed solution is 0.1-1 g/L, and the mass ratio of the carbon nanotube to the metal ion is 3-20: 1, the atomic ratio of the ruthenium element to the cobalt element is 1-10: 1, the ultrasonic time is 30-60 min, and the stirring time is 12-72 h. The invention adopts ruthenium trichloride which is the most cheap ruthenium salt, adopts cobalt chloride, cobalt sulfate or cobalt nitrate which are all cheap cobalt salts, has low cost of raw materials, is beneficial to loading the carbon nano tubes with metal ions by controlling the mass concentration of the carbon nano tubes, the mass ratio of the carbon nano tubes to the metal ions and the atomic ratio of ruthenium elements to cobalt elements in a mixed solution, controls the mass of the metal ions loaded on the carbon nano tubes, ensures the catalytic performance of the ruthenium/cobalt-loaded hydrogen evolution catalyst of the carbon nano tubes, uniformly disperses various substances in the solution by controlling the ultrasonic time, realizes the dispersion and loading of the metal ions on the carbon nano tubes by controlling the stirring time, and has no obvious effect if the time is too short or too long.

The preparation method of the carbon nanotube-supported ruthenium-cobalt hydrogen evolution catalyst is characterized in that the temperature of spray drying in the step five is 150-250 ℃, and the flow rate of the mixed solution for spray drying is 100-300 mL/h. The invention ensures that the mixed solution is fully dried into composite powder by controlling the temperature of spray drying and the flow rate of the mixed solution for spray drying, prevents the defects of overhigh temperature, low temperature of the bottom box and incomplete drying caused by the influence of electric energy waste on the performance of the carbon nano tube, and prevents the defects of overlarge flow rate, incomplete drying, too small flow rate and low electric energy waste efficiency.

The preparation method of the carbon nanotube-supported ruthenium-cobalt hydrogen evolution catalyst is characterized in that the heating process in the sixth step is as follows: heating to 200-600 ℃ at the heating rate of 4-10 ℃/min, and then preserving the heat for 0.5-3 h. The invention fully reduces the metal ions loaded by the carbon nano tube by controlling the heating rate, the heating temperature and the heat preservation time, so that the metal ions loaded by the carbon nano tube have proper particle size, thereby ensuring that the ruthenium-cobalt hydrogen evolution catalyst loaded by the carbon nano tube has optimal catalytic performance, preventing the metal particles from growing too large due to the over-low heating rate to influence the deficiency of the catalytic performance, preventing the deficiencies of low heating temperature, short time and incomplete reduction, and preventing the deficiencies of high heating temperature, long time and too large metal particles from growing to influence the catalytic performance.

The preparation method of the carbon nanotube-supported ruthenium-cobalt hydrogen evolution catalyst is characterized in that the volume fraction of hydrogen in the hydrogen-argon mixed atmosphere in the sixth step is 7-9%, and the balance is argon. The invention ensures that metal ions loaded by the carbon nano tube are fully reduced by controlling the volume fraction of hydrogen in the hydrogen-argon mixed atmosphere.

The preparation method of the carbon nanotube-supported ruthenium-cobalt hydrogen evolution catalyst is characterized in that in the seventh step, the mass fraction of ethanol in the ethanol solution is 30-70%, the heating and stirring time is 1-6 h, and the temperature is 40-80 ℃. The invention fully modifies the precursor powder by controlling the mass fraction of ethanol, the heating and stirring time and temperature, adds functional groups such as load hydroxyl groups and the like on the precursor powder, improves the wettability and the dispersibility of the catalyst in water, ensures the highest reaction efficiency, prevents the defects of strong volatility caused by overlarge mass fraction of the ethanol, large loss and unobvious modification effect caused by overlarge mass fraction, prevents the defects of too short time, too few and unobvious modification effects, too long time, mostly completed modification and unobvious increase duration effect, and prevents the defects of long time required by too low temperature and too high volatility caused by too high temperature.

Compared with the prior art, the invention has the following advantages:

1. the invention improves the load capacity of metal ions on the carbon nano tube by loading a plurality of functional groups such as hydroxyl, carboxyl, amino and the like on the surface of the carbon nano tube, then loading ruthenium and cobalt on the surface of the carbon nano tube, then carrying out spray drying to realize the uniform dispersion of the ruthenium and cobalt loaded solution of the carbon nano tube, thus preparing the carbon nano tube ruthenium-loaded cobalt composite powder with the micro-nano structure, heating and preserving the temperature of the composite powder under the hydrogen-argon mixed atmosphere to reduce ruthenium and cobalt loaded on the carbon nano tube into simple substances, improving the catalytic performance, finally heating and stirring the mixture in an ethanol solution to realize the cleaning of the catalyst and introduce hydroxyl to improve the wettability of the catalyst in the aqueous solution, improving the application performance of the carbon nano tube ruthenium-loaded cobalt hydrogen evolution catalyst, wherein the average particle size of metal particles in the prepared carbon nano tube ruthenium-loaded cobalt hydrogen evolution catalyst is less than 8nm, excellent hydrogen evolution performance was exhibited in both 0.5M sulfuric acid solution and 1M potassium hydroxide solution.

2. The catalyst treatment solution of the invention does not need to introduce various dispersants and additives, so that the subsequent washing process is reduced, and the obtained product has higher purity.

3. Ruthenium and cobalt in the carbon nano tube ruthenium-loaded cobalt hydrogen evolution catalyst prepared by the method have certain hydrogen evolution performance, and after the ruthenium element and the cobalt element are mixed, the synergistic effect of the elements is favorable for improving the catalytic performance, so that the hydrogen evolution performance of the carbon nano tube ruthenium-loaded cobalt hydrogen evolution catalyst is further improved.

4. The method for preparing the carbon nano tube ruthenium-loaded cobalt hydrogen evolution catalyst is simple and convenient, has controllable components and good performance, and can be popularized in a large scale.

The technical solution of the present invention is further described in detail by the accompanying drawings and examples.

Drawings

Fig. 1 is a TEM image of the ruthenium-supported cobalt hydrogen evolution catalyst on carbon nanotubes prepared in example 1 of the present invention.

Detailed Description

Example 1

The embodiment comprises the following steps:

step one, placing the carbon nano tube in an ethanol solution, heating and stirring, then standing and settling, removing supernatant, and then cleaning with deionized water to obtain an ethanol-treated carbon nano tube; the carbon nano tube is a multi-walled carbon nano tube, the mass fraction of ethanol in the ethanol solution is 40%, the heating and stirring time is 4h, and the temperature is 50 ℃;

step two, placing the ethanol-treated carbon nano tube obtained in the step one in a mixed solution, heating and stirring, then standing and settling, removing supernatant, and then cleaning with deionized water to neutrality to obtain a mixed solution-treated carbon nano tube; the mixed solution consists of a hydrogen peroxide solution and a dilute nitric acid solution; the concentration of hydrogen peroxide in the mixed solution is 2mol/L, the concentration of nitric acid is 1mol/L, the heating and stirring time is 7h, and the temperature is 80 ℃;

step three, placing the mixed solution treated carbon nano tube obtained in the step two in an ethylenediamine solution, then heating and stirring, then standing and settling, removing supernatant liquor, and then cleaning with deionized water to obtain an ethylenediamine treated carbon nano tube; the concentration of ethylenediamine in the ethylenediamine solution is 1mol/L, the heating and stirring time is 3 hours, and the temperature is 60 ℃;

step four, adding the ethylenediamine treated carbon nano tube, the ruthenium salt and the cobalt salt obtained in the step three into deionized water, and then sequentially carrying out ultrasonic treatment and stirring to obtain a mixed solution; the ruthenium salt is ruthenium trichloride hydrate, the cobalt salt is cobalt chloride, the concentration of the carbon nano tube in the mixed solution is 0.2g/L, and the mass ratio of the carbon nano tube to the metal ions is 5: 1, the atomic ratio of ruthenium element to cobalt element is 5: 1, the ultrasonic treatment time is 30min, and the stirring time is 24 h;

step five, performing spray drying on the mixed solution obtained in the step four by using a spray dryer to obtain composite powder; the temperature of the spray drying is 150 ℃, and the flow rate of the mixed solution for spray drying is 300 mL/h;

step six, heating the composite powder obtained in the step five under a hydrogen-argon mixed atmosphere to obtain precursor powder; the heating process comprises the following steps: heating to 200 ℃ at a heating rate of 5 ℃/min, and then preserving heat for 3 h; the volume fraction of hydrogen in the hydrogen-argon mixed atmosphere is 8%, and the balance is argon;

step seven, placing the precursor powder obtained in the step six in an ethanol solution, heating and stirring, then standing and settling, removing supernatant, cleaning with deionized water, and drying to obtain the carbon nano tube supported ruthenium-cobalt hydrogen evolution catalyst; the mass fraction of ethanol in the ethanol solution is 30%, the heating and stirring time is 1.5h, and the temperature is 50 ℃.

Fig. 1 is a TEM image of the catalyst for hydrogen evolution on ruthenium and cobalt carried by carbon nanotubes prepared in this example, and it can be seen from fig. 1 that ruthenium and cobalt particles in the prepared catalyst for hydrogen evolution on ruthenium and cobalt carried by carbon nanotubes are attached to carbon nanotubes, and the average particle size of the ruthenium and cobalt particles is less than 8nm and the distribution is uniform.

The hydrogen evolution catalyst of ruthenium-cobalt carried by carbon nano tube prepared in the embodiment is tested and analyzed by an electrochemical workstation, and H is 0.5M₂SO₄In solution, the catalyst is at 10mA/cm²The overpotential of hydrogen evolution is 40 mv; in a 1M KOH solution, the catalyst was at 10mA/cm²The overpotential for hydrogen evolution is 44mv, and the catalyst prepared in this example has good hydrogen evolution characteristics.

Example 2

The embodiment comprises the following steps:

step one, placing the carbon nano tube in an ethanol solution, heating and stirring, then standing and settling, removing supernatant, and then cleaning with deionized water to obtain an ethanol-treated carbon nano tube; the carbon nano tube is a multi-walled carbon nano tube, the mass fraction of ethanol in the ethanol solution is 70%, the heating and stirring time is 6h, and the temperature is 40 ℃;

step two, placing the ethanol-treated carbon nano tube obtained in the step one in a mixed solution, heating and stirring, then standing and settling, removing supernatant, and then cleaning with deionized water to neutrality to obtain a mixed solution-treated carbon nano tube; the mixed solution consists of a hydrogen peroxide solution and a dilute nitric acid solution; the concentration of hydrogen peroxide in the mixed solution is 4mol/L, the concentration of nitric acid is 2mol/L, the heating and stirring time is 10h, and the temperature is 40 ℃;

step three, placing the mixed solution treated carbon nano tube obtained in the step two in an ethylenediamine solution, then heating and stirring, then standing and settling, removing supernatant liquor, and then cleaning with deionized water to obtain an ethylenediamine treated carbon nano tube; the concentration of ethylenediamine in the ethylenediamine solution is 2mol/L, the heating and stirring time is 1h, and the temperature is 80 ℃;

step four, adding the ethylenediamine treated carbon nano tube, the ruthenium salt and the cobalt salt obtained in the step three into deionized water, and then sequentially carrying out ultrasonic treatment and stirring to obtain a mixed solution; the ruthenium salt is ruthenium trichloride hydrate, the cobalt salt is cobalt sulfate, the concentration of the carbon nano tube in the mixed solution is 0.1g/L, and the mass ratio of the carbon nano tube to the metal ions is 20: 1, the atomic ratio of ruthenium element to cobalt element is 1: 1, the ultrasonic treatment time is 60min, and the stirring time is 12 h;

step five, performing spray drying on the mixed solution obtained in the step four by using a spray dryer to obtain composite powder; the temperature of the spray drying is 250 ℃, and the flow rate of the mixed solution for spray drying is 100 mL/h;

step six, heating the composite powder obtained in the step five under a hydrogen-argon mixed atmosphere to obtain precursor powder; the heating process comprises the following steps: heating to 600 ℃ at the heating rate of 10 ℃/min and then preserving heat for 0.5 h; the volume fraction of hydrogen in the hydrogen-argon mixed atmosphere is 7%, and the balance is argon;

step seven, placing the precursor powder obtained in the step six in an ethanol solution, heating and stirring, then standing and settling, removing supernatant, cleaning with deionized water, and drying to obtain the carbon nano tube supported ruthenium-cobalt hydrogen evolution catalyst; the mass fraction of ethanol in the ethanol solution is 70%, the heating and stirring time is 6h, and the temperature is 40 ℃.

Through detection, in the carbon nanotube-supported ruthenium-cobalt hydrogen evolution catalyst prepared in the embodiment, ruthenium-cobalt particles are attached to the carbon nanotube, and the average particle size of the ruthenium-cobalt particles is less than 8nm and the ruthenium-cobalt particles are uniformly distributed; the hydrogen evolution catalyst of ruthenium-cobalt carried by carbon nano tube prepared in the embodiment is tested and analyzed by an electrochemical workstation, and H is 0.5M₂SO₄In solution, the catalyst is at 10mA/cm²The overpotential of hydrogen evolution is 41 mv; in a 1M KOH solution, the catalyst was at 10mA/cm²The overpotential for hydrogen evolution is 43mv, and the catalyst prepared in this example has good hydrogen evolution characteristics.

Example 3

The embodiment comprises the following steps:

step one, placing the carbon nano tube in an ethanol solution, heating and stirring, then standing and settling, removing supernatant, and then cleaning with deionized water to obtain an ethanol-treated carbon nano tube; the carbon nano tube is a multi-walled carbon nano tube, the mass fraction of ethanol in the ethanol solution is 30%, the heating and stirring time is 10 hours, and the temperature is 80 ℃;

step two, placing the ethanol-treated carbon nano tube obtained in the step one in a mixed solution, heating and stirring, then standing and settling, removing supernatant, and then cleaning with deionized water to neutrality to obtain a mixed solution-treated carbon nano tube; the mixed solution consists of a hydrogen peroxide solution and a dilute nitric acid solution; the concentration of hydrogen peroxide in the mixed solution is 1mol/L, the concentration of nitric acid is 3mol/L, the heating and stirring time is 4h, and the temperature is 60 ℃;

step three, placing the mixed solution treated carbon nano tube obtained in the step two in an ethylenediamine solution, then heating and stirring, then standing and settling, removing supernatant liquor, and then cleaning with deionized water to obtain an ethylenediamine treated carbon nano tube; the concentration of ethylenediamine in the ethylenediamine solution is 0.5mol/L, the heating and stirring time is 4h, and the temperature is 40 ℃;

step four, adding the ethylenediamine treated carbon nano tube, the ruthenium salt and the cobalt salt obtained in the step three into deionized water, and then sequentially carrying out ultrasonic treatment and stirring to obtain a mixed solution; the ruthenium salt is ruthenium trichloride hydrate, the cobalt salt is cobalt nitrate hydrate, the concentration of the carbon nano tube in the mixed solution is 1g/L, and the mass ratio of the carbon nano tube to the metal ions is 3: 1, the atomic ratio of ruthenium element to cobalt element is 10: 1, the ultrasonic treatment time is 40min, and the stirring time is 72 h;

step five, performing spray drying on the mixed solution obtained in the step four by using a spray dryer to obtain composite powder; the temperature of the spray drying is 200 ℃, and the flow rate of the mixed solution for spray drying is 200 mL/h;

step six, heating the composite powder obtained in the step five under a hydrogen-argon mixed atmosphere to obtain precursor powder; the heating process comprises the following steps: heating to 300 ℃ at the heating rate of 4 ℃/min and then preserving heat for 2 h; the volume fraction of hydrogen in the hydrogen-argon mixed atmosphere is 9%, and the balance is argon;

step seven, placing the precursor powder obtained in the step six in an ethanol solution, heating and stirring, then standing and settling, removing supernatant, cleaning with deionized water, and drying to obtain the carbon nano tube supported ruthenium-cobalt hydrogen evolution catalyst; the mass fraction of ethanol in the ethanol solution is 50%, the heating and stirring time is 1h, and the temperature is 80 ℃.

Through detection, in the carbon nanotube-supported ruthenium-cobalt hydrogen evolution catalyst prepared in the embodiment, ruthenium-cobalt particles are attached to the carbon nanotube, and the average particle size of the ruthenium-cobalt particles is less than 8nm and the ruthenium-cobalt particles are uniformly distributed; the hydrogen evolution catalyst of ruthenium-cobalt carried by carbon nano tube prepared in the embodiment is tested and analyzed by an electrochemical workstation, and H is 0.5M₂SO₄In solution, the catalyst is at 10mA/cm²The overpotential of hydrogen evolution is 42 mv; in a 1M KOH solution, the catalyst was at 10mA/cm²The overpotential for hydrogen evolution is 45mv, and the catalyst prepared in the example has good hydrogen evolution characteristics.

The above description is only for the preferred embodiment of the present invention, and is not intended to limit the present invention in any way. Any simple modification, change and equivalent changes of the above embodiments according to the technical essence of the invention are still within the protection scope of the technical solution of the invention.