阅读说明：本技术 一种碳纳米管负载的金纳米簇催化剂的制备方法及其应用 (Preparation method and application of carbon nanotube-loaded gold nanocluster catalyst ) 是由 王志江 孙堃 于 2021-06-28 设计创作，主要内容包括：一种碳纳米管负载的金纳米簇催化剂的制备方法及其应用,涉及金纳米簇催化剂制备技术领域。本发明的目的是为了解决传统的贵金属Au基催化剂电催化还原CO-2为CO的催化性能差以及价格昂贵的问题。本发明利用碳纳米管的高导电性和高比表面积的特点,将其作为金纳米簇的载体,增加了催化剂的导电性,碳纳米管表面丰富的缺陷为金纳米簇提供了丰富的稳定附着点,增加了催化剂的催化稳定性；金纳米簇与载体碳纳米管的缺陷紧密结合,为金纳米簇的电子结构改变提供了契机,进一步在减少贵金属金用量的前提下提升了CO-2还原制备CO的性能,可实现超过95％的CO法拉第效率。本发明可获得一种碳纳米管负载的金纳米簇催化剂的制备方法及其应用。(A preparation method and application of a gold nanocluster catalyst loaded by a carbon nano tube relate to the technical field of preparation of gold nanocluster catalysts. The invention aims to solve the problem of electrocatalytic reduction of CO by using a traditional noble metal Au-based catalyst 2 The problem of poor catalytic performance and high price of CO. The invention utilizes the characteristics of high conductivity and high specific surface area of the carbon nano tube as a carrier of the gold nano cluster, increases the conductivity of the catalyst, provides rich stable attachment points for the gold nano cluster due to rich defects on the surface of the carbon nano tube, and increases the catalytic stability of the catalyst; the defects of the gold nanoclusters and the carrier carbon nanotubes are tightly combined, so that a chance is provided for changing the electronic structure of the gold nanoclusters, and the CO is further promoted on the premise of reducing the consumption of noble metal gold 2 The performance of reducing and preparing CO can realize the Faraday efficiency of CO of over 95 percent. The invention can obtain gold loaded by the carbon nano tubeA preparation method and application of a nano-cluster catalyst.)

1. A preparation method of a carbon nano tube loaded gold nano cluster catalyst is characterized by comprising the following steps:

firstly, weighing:

weighing a carbon nanotube, a gold molecular catalyst, a Nafion solution and a solvent, wherein the ratio of the mass of the carbon nanotube to the mass of the gold molecular catalyst to the volume of the Nafion solution to the volume of the solvent is (0.1-40) mg: (0.1-40) mg: (0.4-160) μ L: (0.025-10) mL;

secondly, compounding and preparing a precursor working electrode: adding the carbon nano tube, the gold molecular catalyst and the Nafion solution weighed in the step one into a solvent, and carrying out ultrasonic mixing to obtain a precursor mixed solution; uniformly spraying the precursor mixed solution on carbon paper, and drying after spraying to obtain a precursor working electrode;

thirdly, preparing the carbon nano tube loaded ultra-small gold nano cluster catalyst:

placing a precursor working electrode in a cathode area of an H-shaped electrolytic cell as a cathode, wherein the cathode area and an anode area of the H-shaped electrolytic cell are separated by a Nafion proton exchange membrane, a graphite or platinum electrode is used as an anode in the anode area, and a saturated calomel electrode is placed in the cathode area as a reference electrode; and adding carbonate electrolyte into the cathode area and the anode area, and electrifying the cathode area under the protection of inert gas to react to obtain the gold nanocluster catalyst loaded by the carbon nano tube.

2. The method of claim 1, wherein the ratio of the mass of the carbon nanotubes, the mass of the gold molecular catalyst, the volume of the Nafion solution and the volume of the solvent in the first step is 20 mg: 20 mg: 160 μ L: 5 mL.

3. The method according to claim 1 or 2, wherein the gold molecular catalyst in the first step is trimethylphosphine chloroauric acid, triphenylphosphine gold chloride or dimethyl sulfide gold chloride, and the solvent is methanol, ethanol, acetone, propanol or isopropanol.

4. The method for preparing a carbon nanotube-supported gold nanocluster catalyst according to claim 1, wherein the time for ultrasonic mixing in the second step is 10-180 min.

5. The method for preparing a carbon nanotube-supported gold nanocluster catalyst according to claim 1, wherein the ratio of the volume of the precursor mixed solution to the area of the carbon paper in the second step is (0.01 to 1) mL: 1cm²。

6. The method for preparing a carbon nanotube-supported gold nanocluster catalyst according to claim 1, wherein the drying temperature after the spraying in the second step is 20 to 80 ℃ and the drying time is 5 to 300 min.

7. The method for preparing a carbon nanotube-supported gold nanocluster catalyst according to claim 1, wherein the carbonate electrolyte in the third step is potassium carbonate, sodium carbonate, potassium bicarbonate or sodium bicarbonate, and the concentration is 0.1-5 mol/L.

8. The method for preparing a carbon nanotube-supported gold nanocluster catalyst according to claim 1, wherein in the third step, the cathode region is electrified to react for 1-180 min under the protection of nitrogen or argon.

9. The method of claim 1, wherein the energizing voltage in the third step is-1V to-2V.

10. The use of the carbon nanotube-supported gold nanocluster catalyst according to claim 1, wherein the carbon nanotube-supported gold nanocluster catalyst is used as a working electrode for electrocatalytic reduction of CO₂Preparing CO; the carbon nano tube loaded gold nano cluster catalyst is used for electrocatalytic reduction of CO₂The specific steps for preparing CO are as follows:

(1) assembling: an H-shaped electrolytic cell adopting a three-electrode system is adopted, a carbon rod is arranged in an anode chamber to serve as a counter electrode, a saturated calomel electrode is arranged in a cathode chamber to serve as a reference electrode, a Nafion membrane is used for separating the cathode chamber from the anode chamber, a gas area and a liquid area of the cathode chamber are separated by a gas diffusion electrode, potassium bicarbonate with the concentration of 0.5mol/L is used as electrolyte and added into the cathode area, and a sealing element is adopted to seal the cathode area, so that the electro-catalytic reduction CO is obtained₂A CO production device;

(2) electrocatalytic reduction: CO injection via digital gas flow controller₂Introducing gas into the electrolyte in the cathode region, wherein the gas introduction flow rate is 10-30 mL/min; under the voltage of-1V to-2V, the electrocatalytic reduction of CO is completed₂And (5) preparing CO.

Technical Field

The invention relates to the technical field of gold nanocluster catalyst preparation, in particular to a preparation method and application of a carbon nanotube-loaded ultra-small gold nanocluster catalyst.

Background

Currently, the energy structure of human society relies heavily on the combustion of non-renewable fossil energy, and it is difficult to achieve the goal of sustainable development. The large consumption of fossil energy is accompanied by the generation of large quantities of greenhouse gasesBulk CO₂Leading to serious environmental and social problems such as greenhouse effect and energy crisis. With the development and progress of science and technology, human needs to solve CO in this century₂Too high concentration. Electrocatalytic reduction of CO₂The technology is a new technical means, and the CO is reduced by electrocatalysis₂Can consume excessive CO in the atmosphere₂Thus obtaining the carbon-based energy chemicals, such as methanol, carbon monoxide, methane, ethylene and the like, and achieving the effect of killing two birds with one stone. At the same time, electrocatalysis is compared to other CO₂The treatment means has the advantages of simpler and more convenient operation and higher efficiency, and particularly has wide application prospect considering the application of clean electric energy sources such as wind power, hydropower and the like. However, the current bottleneck problem is to develop a new electrocatalyst with higher catalytic performance and catalytic stability.

CO₂The products of electrocatalytic reduction are quite complex, and more than ten products such as formic acid, carbon monoxide, acetic acid, ethanol, ethylene and the like can be generated by transferring different electron numbers, and the generation of a single reduction product by a single reaction path is the first problem of current development consideration of electrocatalysts. Efficient electrocatalytic reduction of CO with current technology₂Has a very high economic prospect for CO, because CO is an important raw material for Fischer-Tropsch reaction for industrially synthesizing higher hydrocarbon products. Current CO₂The reduction electrocatalyst can be mainly divided into a metal catalyst, a nonmetal catalyst and a molecular catalyst. Metal species to CO₂The reduction product has a decisive effect, and the CO of the Bi, Sn and other element catalysts₂The reduction products are usually formic acid, the reduction products of elemental catalysts like Au, Ag and Zn are usually CO, and Cu catalysts can produce more complex hydrocarbons like ethylene, ethanol and propanol, etc. The current research mainly focuses on means of regulating and controlling the microstructure of the catalyst, optimizing the proportion of active sites, changing the electronic structure and the like to improve the catalytic performance. The existing catalyst preparation method has the disadvantages of more steps, complex operation, difficulty in realizing macro preparation, low atomic utilization rate of elements and difficulty in guaranteeing catalytic performance.

Au element to CO among all the elements studied₂Reduction CO preparing toolThe gold-based catalyst has the highest selectivity, but Au belongs to a noble metal element, the reserves are rare, the price is high, the catalytic performance of the current gold-based catalyst is not high, the atom utilization rate is low, and the large-scale application of the gold-based catalyst is limited. Therefore, it is highly desirable to improve the quality activity and catalytic performance of Au-based catalysts and to realize high-efficiency CO₂The electrocatalysis reduction is used for preparing CO, and the industrial application process of the Au-based catalyst is promoted.

Disclosure of Invention

The invention aims to solve the problem of electrocatalytic reduction of CO by using a traditional noble metal Au-based catalyst₂The preparation method and the application of the carbon nano tube supported gold nano cluster catalyst are provided for solving the problems of poor catalytic performance and high price of CO.

A preparation method of a carbon nano tube loaded gold nano cluster catalyst comprises the following steps:

firstly, weighing:

weighing a carbon nanotube, a gold molecular catalyst, a Nafion solution and a solvent, wherein the ratio of the mass of the carbon nanotube to the mass of the gold molecular catalyst to the volume of the Nafion solution to the volume of the solvent is (0.1-40) mg: (0.1-40) mg: (0.4-160) μ L: (0.025-10) mL;

secondly, compounding and preparing a precursor working electrode: adding the carbon nano tube, the gold molecular catalyst and the Nafion solution weighed in the step one into a solvent, and carrying out ultrasonic mixing to obtain a precursor mixed solution; uniformly spraying the precursor mixed solution on carbon paper, and drying after spraying to obtain a precursor working electrode;

thirdly, preparing the carbon nano tube loaded ultra-small gold nano cluster catalyst:

placing a precursor working electrode in a cathode area of an H-shaped electrolytic cell as a cathode, wherein the cathode area and an anode area of the H-shaped electrolytic cell are separated by a Nafion proton exchange membrane, a graphite or platinum electrode is used as an anode in the anode area, and a saturated calomel electrode is placed in the cathode area as a reference electrode; and adding carbonate electrolyte into the cathode area and the anode area, and electrifying the cathode area under the protection of inert gas to react to obtain the gold nanocluster catalyst loaded by the carbon nano tube.

A kind ofApplication of carbon nano tube loaded gold nanocluster catalyst serving as working electrode for electrocatalytic reduction of CO₂Preparing CO; the carbon nano tube loaded gold nano cluster catalyst is used for electrocatalytic reduction of CO₂The specific steps for preparing CO are as follows:

(1) assembling: an H-shaped electrolytic cell adopting a three-electrode system is adopted, a carbon rod is arranged in an anode chamber to serve as a counter electrode, a saturated calomel electrode is arranged in a cathode chamber to serve as a reference electrode, a Nafion membrane is used for separating the cathode chamber from the anode chamber, a gas area and a liquid area of the cathode chamber are separated by a gas diffusion electrode, potassium bicarbonate with the concentration of 0.5mol/L is used as electrolyte and added into the cathode area, and a sealing element is adopted to seal the cathode area, so that the electro-catalytic reduction CO is obtained₂A CO production device;

(2) electrocatalytic reduction: CO injection via digital gas flow controller₂Introducing gas into the electrolyte in the cathode region, wherein the gas introduction flow rate is 10-30 mL/min; under the voltage of-1V to-2V, the electrocatalytic reduction of CO is completed₂And (5) preparing CO.

The invention has the beneficial effects that:

(1) the preparation method of the carbon nanotube-loaded gold nanocluster catalyst provided by the invention utilizes the characteristics of high conductivity and high specific surface area of the carbon nanotube as a carrier of the gold nanocluster, so that the conductivity of the catalyst is increased, the rich defects on the surface of the carbon nanotube provide rich stable attachment points for the gold nanocluster, and the catalytic stability of the catalyst is increased; the defects of the gold nanoclusters and the carrier carbon nanotubes are tightly combined, so that a chance is provided for changing the electronic structure of the gold nanoclusters, and the CO is further promoted on the premise of reducing the consumption of noble metal gold₂The performance of reducing and preparing CO can realize the Faraday efficiency of CO of over 95 percent. The gold molecular catalyst is a precursor, and abundant atomic-level dispersed gold atoms of the gold molecular catalyst can form ultra-small gold nanoclusters on the surface of the carbon nanotube under the action of current, so that the utilization rate of the gold atoms of the catalyst is greatly improved.

(2) The invention adopts a simple electrochemical synthesis method to prepare the carbon nano tube loaded ultra-small gold nano cluster catalyst, and realizes the uniform dispersion of the ultra-small gold nano cluster on the carbon nano tube. The synthesis method is simple and convenient, the catalytic activity and stability of the catalyst are excellent, the preparation cost of the catalyst can be greatly reduced, and the catalyst has wide application prospect.

The invention can obtain a preparation method and application of a carbon nano tube loaded gold nano cluster catalyst.

Drawings

Fig. 1 is a scanning electron microscope photograph of the carbon nanotube-supported gold nanocluster catalyst prepared in example 1;

fig. 2 is a transmission electron microscope photograph of the carbon nanotube-supported gold nanocluster catalyst prepared in example 1;

fig. 3 is a high-resolution transmission electron microscope photograph of the carbon nanotube-supported gold nanocluster catalyst prepared in example 1;

FIG. 4 is a HAADF-STEM diagram of the carbon nanotube-supported gold nanocluster catalyst prepared in example 1;

fig. 5 is an X-ray diffraction pattern in which a represents an X-ray diffraction pattern of the carbon nanotube-supported gold nanocluster catalyst prepared in example 1 and b represents an X-ray diffraction pattern of carbon paper;

fig. 6 is an X-ray photoelectron spectrum of the carbon nanotube-supported gold nanocluster catalyst prepared in example 1;

FIG. 7 shows the electrocatalytic reduction of CO by the carbon nanotube-supported gold nanocluster catalyst prepared in example 1₂Graph of faradaic efficiency for CO;

FIG. 8 is an electrocatalytic reduction of CO by the carbon nanotube-supported gold nanocluster catalyst prepared in example 1₂The current density of CO is plotted.

Detailed Description

The first embodiment is as follows: the preparation method of the carbon nanotube-supported gold nanocluster catalyst in the embodiment comprises the following steps:

firstly, weighing:

weighing a carbon nanotube, a gold molecular catalyst, a Nafion solution and a solvent, wherein the ratio of the mass of the carbon nanotube to the mass of the gold molecular catalyst to the volume of the Nafion solution to the volume of the solvent is (0.1-40) mg: (0.1-40) mg: (0.4-160) μ L: (0.025-10) mL;

secondly, compounding and preparing a precursor working electrode: adding the carbon nano tube, the gold molecular catalyst and the Nafion solution weighed in the step one into a solvent, and carrying out ultrasonic mixing to obtain a precursor mixed solution; uniformly spraying the precursor mixed solution on carbon paper, and drying after spraying to obtain a precursor working electrode;

thirdly, preparing the carbon nano tube loaded ultra-small gold nano cluster catalyst:

placing a precursor working electrode in a cathode area of an H-shaped electrolytic cell as a cathode, wherein the cathode area and an anode area of the H-shaped electrolytic cell are separated by a Nafion proton exchange membrane, a graphite or platinum electrode is used as an anode in the anode area, and a saturated calomel electrode is placed in the cathode area as a reference electrode; and adding carbonate electrolyte into the cathode area and the anode area, and electrifying the cathode area under the protection of inert gas to react to obtain the gold nanocluster catalyst loaded by the carbon nano tube.

The beneficial effects of the embodiment are as follows:

(1) according to the preparation method of the carbon nanotube-supported gold nanocluster catalyst, the carbon nanotube is used as a carrier of the gold nanocluster by utilizing the characteristics of high conductivity and high specific surface area of the carbon nanotube, so that the conductivity of the catalyst is increased, the rich defects on the surface of the carbon nanotube provide rich stable attachment points for the gold nanocluster, and the catalytic stability of the catalyst is increased; the defects of the gold nanoclusters and the carrier carbon nanotubes are tightly combined, so that a chance is provided for changing the electronic structure of the gold nanoclusters, and the CO is further promoted on the premise of reducing the consumption of noble metal gold₂The performance of reducing and preparing CO can realize the Faraday efficiency of CO of over 95 percent. The gold molecular catalyst is a precursor, and abundant atomic-level dispersed gold atoms of the gold molecular catalyst can form ultra-small gold nanoclusters on the surface of the carbon nanotube under the action of current, so that the utilization rate of the gold atoms of the catalyst is greatly improved.

(2) The embodiment adopts a simple electrochemical synthesis method to prepare the carbon nano tube loaded ultra-small gold nano cluster catalyst, and realizes the uniform dispersion of the ultra-small gold nano cluster on the carbon nano tube. The synthesis method is simple and convenient, the catalytic activity and stability of the catalyst are excellent, the preparation cost of the catalyst can be greatly reduced, and the catalyst has wide application prospect.

The second embodiment is as follows: the present embodiment differs from the present embodiment in that: the ratio of the mass of the carbon nanotube, the mass of the gold molecular catalyst, and the volume of the Nafion solution to the volume of the solvent in the first step is 20 mg: 20 mg: 160 μ L: 5 mL.

Other steps are the same as those in the first embodiment.

The third concrete implementation mode: the first or second differences from the present embodiment are as follows: the gold molecular catalyst in the first step is trimethylphosphine chloroauric acid, triphenylphosphine gold chloride or dimethyl sulfide gold chloride, and the solvent is methanol, ethanol, acetone, propanol or isopropanol.

The other steps are the same as those in the first or second embodiment.

The fourth concrete implementation mode: the difference between this embodiment and one of the first to third embodiments is as follows: and in the second step, the ultrasonic mixing time is 10-180 min.

The other steps are the same as those in the first to third embodiments.

The fifth concrete implementation mode: the difference between this embodiment and one of the first to fourth embodiments is: and the ratio of the volume of the precursor mixed solution to the area of the carbon paper in the second step is (0.01-1) mL: 1cm²。

The other steps are the same as those in the first to fourth embodiments.

The sixth specific implementation mode: the difference between this embodiment and one of the first to fifth embodiments is as follows: and in the second step, the drying temperature after the spraying is finished is 20-80 ℃, and the drying time is 5-300 min.

The other steps are the same as those in the first to fifth embodiments.

The seventh embodiment: the difference between this embodiment and one of the first to sixth embodiments is: the carbonate electrolyte in the third step is potassium carbonate, sodium carbonate, potassium bicarbonate or sodium bicarbonate, and the concentration is 0.1-5 mol/L.

The other steps are the same as those in the first to sixth embodiments.

The specific implementation mode is eight: the difference between this embodiment and one of the first to seventh embodiments is: and in the third step, the cathode region is electrified under the protection of nitrogen or argon for reaction for 1-180 min.

The other steps are the same as those in the first to seventh embodiments.

The specific implementation method nine: the difference between this embodiment and the first to eighth embodiments is: the electrifying voltage in the third step is-1V to-2V.

The other steps are the same as those in the first to eighth embodiments.

The detailed implementation mode is ten: in this embodiment, the carbon nanotube-supported gold nanocluster catalyst is used as a working electrode for electrocatalytic reduction of CO₂Preparing CO; the carbon nano tube loaded gold nano cluster catalyst is used for electrocatalytic reduction of CO₂The specific steps for preparing CO are as follows:

(1) assembling: an H-shaped electrolytic cell adopting a three-electrode system is adopted, a carbon rod is arranged in an anode chamber to serve as a counter electrode, a saturated calomel electrode is arranged in a cathode chamber to serve as a reference electrode, a Nafion membrane is used for separating the cathode chamber from the anode chamber, a gas area and a liquid area of the cathode chamber are separated by a gas diffusion electrode, potassium bicarbonate with the concentration of 0.5mol/L is used as electrolyte and added into the cathode area, and a sealing element is adopted to seal the cathode area, so that the electro-catalytic reduction CO is obtained₂A CO production device;

(2) electrocatalytic reduction: CO injection via digital gas flow controller₂Introducing gas into the electrolyte in the cathode region, wherein the gas introduction flow rate is 10-30 mL/min; under the voltage of-1V to-2V, the electrocatalytic reduction of CO is completed₂And (5) preparing CO.

The following examples were used to demonstrate the beneficial effects of the present invention:

example 1: a preparation method of a carbon nano tube loaded gold nano cluster catalyst comprises the following steps:

firstly, weighing:

weighing carbon nanotubes, trimethylphosphine chloroauric acid, a Nafion solution and isopropanol, wherein the ratio of the mass of the carbon nanotubes, the mass of the trimethylphosphine chloroauric acid, the volume of the Nafion solution and the volume of the isopropanol is 20 mg: 20 mg: 160 μ L: 5 mL;

secondly, compounding and preparing a precursor working electrode: adding the carbon nano tube, the trimethylphosphine chloroauric acid and the Nafion solution weighed in the step one into isopropanol, and ultrasonically mixing for 30min to obtain a precursor mixed solution; uniformly spraying the precursor mixed solution to 100cm by using an air spray gun²After the spraying is finished, drying the carbon paper at 80 ℃ for 60min to obtain a precursor working electrode;

thirdly, preparing the carbon nano tube loaded ultra-small gold nano cluster catalyst:

placing a precursor working electrode in a cathode area of an H-shaped electrolytic cell as a cathode, wherein the cathode area and an anode area of the H-shaped electrolytic cell are separated by a Nafion proton exchange membrane, a graphite or platinum electrode is used as an anode in the anode area, and a saturated calomel electrode is placed in the cathode area as a reference electrode; adding potassium bicarbonate electrolyte into the cathode region and the anode region, and electrifying the cathode region under the protection of argon at-1.2V for reaction for 30min to obtain the gold nanocluster catalyst loaded by the carbon nanotube.

Fig. 1 is a scanning electron microscope photograph of the carbon nanotube-supported gold nanocluster catalyst prepared in example 1, and it can be seen from fig. 1 that the catalyst can obviously observe intact carbon nanotubes in a micrometer scale, and the diameter of the carbon nanotubes is uniformly distributed, and agglomerated gold nanoparticles are not observed.

Fig. 2 is a transmission electron microscope photograph of the carbon nanotube-supported gold nanocluster catalyst prepared in example 1, and it can be seen that the carbon nanotube has a complete morphology, the nanotube structure is not changed, and the dark substances are uniformly distributed on the nanotube wall.

Fig. 3 is a high-resolution transmission electron microscope photograph of the carbon nanotube-supported gold nanocluster catalyst prepared in example 1, which shows that a plurality of gold nanoclusters with a particle size of less than 5nm are uniformly attached to the surface of a carbon nanotube, and illustrates that the carbon nanotube-supported gold nanocluster catalyst is successfully prepared by using the method of this embodiment.

Fig. 4 is a HAADF-STEM photograph of the carbon nanotube-supported gold nanocluster catalyst prepared in example 1, in which the bright spots are ultra-small gold nanoclusters, the gold nanoclusters have uniform particle sizes, are all below 5nm, and are uniformly supported on the carbon nanotubes, further illustrating that the carbon nanotube-supported gold nanocluster catalyst is successfully prepared in this example.

X-ray diffraction analysis was performed on the carbon nanotube-supported gold nanocluster catalyst prepared in example 1, wherein a represents an X-ray diffraction spectrum of the carbon nanotube-supported gold nanocluster catalyst prepared in example 1, and b represents an X-ray diffraction spectrum of the carbon paper used, as shown in fig. 5; as can be seen from fig. 5, 5 characteristic peaks of the carbon nanotube-supported gold nanocluster catalyst prepared in example 1 completely coincide with the characteristic peaks of the carbon paper and have the same intensity, which indicates that the 5 characteristic peaks come from the background of the carbon paper, and the remaining disordered characteristic peaks come from the carbon nanotube-supported ultra-small gold nanocluster catalyst.

X-ray photoelectron spectroscopy analysis was performed on the carbon nanotube-supported gold nanocluster catalyst prepared in example 1, and as shown in fig. 6, an Au element peak and a C element peak were clearly seen, which indicates that the carbon nanotube-supported ultra-small gold nanocluster catalyst was successfully prepared in this example.

The carbon nanotube-supported gold nanocluster catalyst prepared in example 1 is used as a working electrode for electrocatalytic reduction of CO₂The area of the working electrode is 1cm multiplied by 2 cm;

the carbon nano tube loaded gold nano cluster catalyst is used for electrocatalytic reduction of CO₂The specific steps for preparing CO are as follows:

(1) assembling: an H-shaped electrolytic cell adopting a three-electrode system is adopted, a carbon rod is arranged in an anode chamber to serve as a counter electrode, a saturated calomel electrode is arranged in a cathode chamber to serve as a reference electrode, a Nafion membrane is used for separating the cathode chamber from the anode chamber, a gas area and a liquid area of the cathode chamber are separated by a gas diffusion electrode, potassium bicarbonate with the concentration of 0.5mol/L is used as electrolyte and added into the cathode area, and a sealing element is adopted to seal the cathode area, so that the electro-catalytic reduction CO is obtained₂A CO production device;

(2) electrocatalytic reduction: CO injection via digital gas flow controller₂Introducing gas into the electrolyte in the cathode region, wherein the gas introduction flow rate is 30 mL/min; CO is carried out at different voltages₂And (3) carrying out electrocatalysis reduction, wherein gas products are analyzed on line by directly flowing gas into a gas sampling ring of the gas chromatograph from a gas outlet of the cathode region, and the analysis is carried out once every 10 minutes.

FIG. 7 is an electrocatalytic reduction of CO₂The Faraday efficiency of CO production is shown as the change of working voltage, and it can be seen from the graph that the carbon nano tube loaded ultra-small gold nano-cluster catalyst can reduce CO at the low voltage of-1V₂CO products are generated, the Faraday efficiency is always higher than 90 percent and can reach more than 95 percent at most along with the increase of the working voltage, and the carbon nano tube loaded ultra-small gold nano-cluster catalyst prepared in the example 1 is a high-performance CO nano-cluster catalyst₂The electrocatalyst is reduced.

FIG. 8 is an electrocatalytic reduction of CO₂The variation graph of the partial current density of the produced CO along with the working voltage shows that the partial current of the produced CO is increased along with the increase of the working voltage, and can reach 30mA/cm at minus 1.8V²The catalyst has excellent CO production capacity and application and research prospects.