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CN-121976244-A - Nanometer metal electrode for fixing ionic liquid and preparation method and application thereof

CN121976244ACN 121976244 ACN121976244 ACN 121976244ACN-121976244-A

Abstract

The invention relates to the field of industrial process waste gas purification, and particularly discloses a nano metal electrode for fixing ionic liquid, a preparation method and application thereof. The method comprises the steps of S1, dispersing nano metal particles and a nitrogen-containing polymer in methanol to obtain a precursor dispersion liquid, then carrying out first ultrasonic treatment on the precursor dispersion liquid, adding Nafion solution, carrying out second ultrasonic treatment to obtain composite ink, S2, coating the composite ink on the surface of a glassy carbon electrode, drying to obtain a modified electrode, S3, coating an ionic liquid solution on the surface of the modified electrode, and drying to obtain the nano metal electrode. According to the invention, the nanometer metal composite electrode constructed by the synergistic modification of the nitrogen-containing polymer-ionic liquid and the two-step process realizes CO 2 selective electroreduction in the amine-based electrolyte, improves the Faraday efficiency of carbon monoxide to 53.6%, and simultaneously remarkably inhibits hydrogen evolution side reaction.

Inventors

  • LIU HANZI
  • SUN ZHIQIANG
  • HOU MINGRUI
  • HE JIAYI
  • YANG ZHE

Assignees

  • 中南大学

Dates

Publication Date
20260505
Application Date
20260128

Claims (10)

  1. 1. A method for preparing a nano-metal electrode for immobilizing an ionic liquid, comprising the steps of: s1, dispersing nano metal particles and a nitrogen-containing polymer in methanol to obtain precursor dispersion liquid; then carrying out first ultrasonic treatment on the precursor dispersion liquid, adding Nafion solution and carrying out second ultrasonic treatment to obtain composite printing ink; S2, coating the composite ink on the surface of the glassy carbon electrode, and drying to obtain a modified electrode; And S3, coating the ionic liquid solution on the surface of the modified electrode, and drying to obtain the nano metal electrode.
  2. 2. The method according to claim 1, wherein in step S1, the nano-metal particles are selected from at least one of the nano-particles of Ag, ni, fe, co.
  3. 3. The method according to claim 1 or 2, wherein in step S1, the nitrogen-containing polymer is selected from at least one of polyaniline, polypyrrole, polyethylenimine, quaternary ammonium salt polymer.
  4. 4. The method according to claim 1 or 2, wherein in step S1, the concentration of the Nafion solution is 3-8% by mass.
  5. 5. The method according to claim 1 or 2, wherein in step S1, the conditions of the first and second ultrasonic treatments are each independently at least satisfied that the ultrasonic power is 200-500W, the temperature is 50-60 ℃ and the time is 30min.
  6. 6. The method according to claim 1 or 2, wherein in step S2, the coating is spraying.
  7. 7. A process according to claim 1 or 2, wherein in step S3, the ionic liquid solution is obtained by dissolving an ionic liquid in an organic solvent, and The ionic liquid is at least one selected from BmimBF 4 、BmimPF 6 and BmimOH.
  8. 8. The method according to claim 1 or 2, wherein in step S3, the organic solvent is selected from at least one of propanol, isopropanol, ethanol, methanol.
  9. 9. A nano-metal electrode for fixing an ionic liquid prepared by the method of any one of claims 1 to 8, comprising: a glassy carbon electrode substrate; The composite catalytic layer is formed on the surface of the glassy carbon electrode substrate, comprises nano metal particles and a nitrogen-containing polymer, and is fixed by a Nafion binder; And the ionic liquid layer is covered on the surface of the composite catalytic layer.
  10. 10. Use of the ionic liquid immobilized nano-metal electrode of claim 9 in electrocatalytic carbon dioxide reduction reactions.

Description

Nanometer metal electrode for fixing ionic liquid and preparation method and application thereof Technical Field The invention relates to the field of industrial process waste gas purification, in particular to a nano metal electrode for fixing ionic liquid, a preparation method and application thereof. Background The electrochemical reduction of carbon dioxide (CO 2 RR) to prepare carbon monoxide (CO) is a potential carbon neutralization technical path, which not only can realize the recycling utilization of CO 2, but also can obtain important chemical raw materials and synthesis gas components. In this technique, the performance of the cathode catalyst (electrode) directly determines the efficiency, selectivity and economy of the reaction. Currently, electrode material research for CO 2 RR has been mainly conducted around metal-based catalysts (such as gold, silver, copper and derivatives thereof), carbon-based materials, and the like. Noble metals such as gold electrodes have high selectivity for reduction of CO 2 to CO, but high cost restricts its large-scale application. Silver electrodes, as a relatively low cost alternative, have yet to have improved CO selectivity and are often accompanied by a violent Hydrogen Evolution Reaction (HER). Copper-based catalysts, while capable of producing multiple carbon products, are challenging to convert CO 2 to single-product CO with high selectivity (Wu Zhizheng. Doctor article of the university of chinese science and technology, 2024; yang Zhenyu, et al. Rare metals, 2025). In recent years, to reduce the amount of noble metals and improve the performance, researchers have developed non-noble metal systems such as nitrogen-doped carbon-supported metal monoatomic catalysts, which show a certain potential in CO 2 RR, but still face the problems of complex preparation, active site density and stability (Guo Xiaolin et al, chemistry report, 2022; she Hui, university of the company, doctor's paper, 2024). In summary, the development of a novel composite electrode with high active site density and stability, excellent reduction activity and low hydrogen evolution reaction is very important to promote the practical breakthrough of the CO 2 electroreduction technology. Disclosure of Invention The invention aims to solve the problems of low selectivity and hydrogen evolution side reaction in the preparation of carbon monoxide by carbon dioxide electrolytic reduction in the prior art. In order to achieve the above object, a first aspect of the present invention provides a method for preparing a nano-metal electrode for immobilizing an ionic liquid, the method comprising the steps of: s1, dispersing nano metal particles and a nitrogen-containing polymer in methanol to obtain precursor dispersion liquid; then carrying out first ultrasonic treatment on the precursor dispersion liquid, adding Nafion solution and carrying out second ultrasonic treatment to obtain composite printing ink; S2, coating the composite ink on the surface of the glassy carbon electrode, and drying to obtain a modified electrode; And S3, coating the ionic liquid solution on the surface of the modified electrode, and drying to obtain the nano metal electrode. According to a second aspect of the present invention, there is provided a nano metal electrode for fixing an ionic liquid prepared by the method of the first aspect, comprising: a glassy carbon electrode substrate; The composite catalytic layer is formed on the surface of the glassy carbon electrode substrate, comprises nano metal particles and a nitrogen-containing polymer, and is fixed by a Nafion binder; And the ionic liquid layer is covered on the surface of the composite catalytic layer. The third aspect of the invention provides an application of the ionic liquid-immobilized nano metal electrode in electrocatalytic carbon dioxide reduction reaction. Compared with the prior art, the invention has at least the following advantages: (1) The nano metal composite electrode for fixing the ionic liquid and the nitrogen-containing polymer provided by the invention has a series of synergistic enhancement beneficial effects in the electrocatalytic carbon dioxide reduction reaction through the unique design of the multi-stage composite structure of nano metal/nitrogen-containing polymer-Nafion-ionic liquid and the corresponding two-step preparation process. The most remarkable core advantage is that in an amine-based electrolyte system, the Faraday efficiency of carbon monoxide of 53.6% can be realized under the potential of-1.4V (vs. Ag/AgCl), and the current density reaches 3.169mA/cm < 2 >. Compared with an electrode without the ionic liquid fixed or an electrode prepared by a simple physical mixing one-step method, the CO selectivity (Faraday efficiency) is greatly improved, the reaction path is effectively guided to a target product CO, and the hydrogen evolution side reaction is obviously inhibited from two aspects of physical barrier and chemical