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CN-121992440-A - Electrolytic seawater hydrogen production catalyst based on metal ruthenium doped copper nanowire composite structure and synthesis method thereof

CN121992440ACN 121992440 ACN121992440 ACN 121992440ACN-121992440-A

Abstract

A catalyst for preparing hydrogen from electrolytic seawater based on the composite structure of Cu-Ru doped nano-wire is prepared from the Cu-Ru skeleton derived from foam copper and the Cu clusters uniformly distributed on its surface through immersing the foam copper in the solution containing sodium hydroxide and oxidizing agent to generate Cu hydroxide nano-wire, immersing in the solution containing Ru salt for introducing Cu, and heat treating in inertial atmosphere and electrochemical reduction. The fine regulation and control of the catalyst structure and components are realized by adjusting the concentration of the reaction solution, the dipping time and the treatment condition. The electrocatalyst provided by the invention has excellent hydrogen evolution activity and long-term stability under the condition of acid seawater electrolysis, effectively solves the problems that a nickel-based current collector is easy to corrode in an acid medium and a traditional platinum-based catalyst is easy to deactivate in natural seawater, and provides a new technical scheme for high-efficiency and stable seawater electrolysis hydrogen production.

Inventors

  • WANG ZHIYU
  • YANG PENGJU

Assignees

  • 大连理工大学

Dates

Publication Date
20260508
Application Date
20260205

Claims (10)

  1. 1. The synthesis method of the electrolytic seawater hydrogen production catalyst based on the metal ruthenium doped copper nanowire composite structure is characterized by comprising the following steps of: Firstly, ultrasonically cleaning the foamy copper to remove organic pollutants and an oxide layer on the surface; secondly, immersing the foam copper into an alkaline oxidation solution containing ammonium persulfate and sodium hydroxide, and reacting at room temperature to generate a copper hydroxide nanowire array in situ on the surface of the foam copper, wherein the copper hydroxide nanowire array is used as a self-supporting electrode of the copper hydroxide nanowire; immersing the self-supporting electrode of the copper hydroxide nanowire obtained in the second step into an aqueous solution containing ruthenium salt for ion exchange reaction, and standing at normal temperature and normal pressure for reaction to uniformly introduce ruthenium species onto the surface of the copper-based nanostructure, thereby obtaining a ruthenium-doped copper hydroxide nanowire electrode; fourthly, carrying out low-temperature heat treatment on the ruthenium-doped copper hydroxide nanowire electrode obtained in the third step under the protection of inert gas, so that the ruthenium-doped copper hydroxide nanowire electrode is converted into an oxide nanowire structure, and a ruthenium-doped copper oxide nanowire electrode is obtained; And fifthly, immersing the copper oxide nanowire electrode obtained in the fourth step in potassium bicarbonate electrolyte, and converting the oxide nanowire into a metal copper nanowire through constant-current electrochemical reduction, and simultaneously forming ruthenium clusters stably loaded on the surface of the metal copper nanowire, thereby finally obtaining the ruthenium-doped copper nanowire composite electrode.
  2. 2. The method for synthesizing the electrolytic seawater hydrogen production catalyst based on the metal ruthenium doped copper nanowire composite structure, which is characterized in that in the first step, foam copper is sequentially ultrasonically cleaned by ethanol, dilute hydrochloric acid solution and deionized water.
  3. 3. The method for synthesizing the catalyst for producing hydrogen by electrolyzing seawater based on the metal ruthenium-doped copper nanowire composite structure of claim 1, wherein in the second step, the concentration of ammonium persulfate in the alkaline oxidation solution is 0.05-0.2M, and the concentration of sodium hydroxide is 0.5-2M.
  4. 4. The method for synthesizing the catalyst for producing hydrogen by electrolyzing seawater based on the metal ruthenium doped copper nanowire composite structure of claim 1, wherein in the second step, the molar ratio of ammonium persulfate to sodium hydroxide in the alkaline oxidation solution is 1:10.
  5. 5. The method for synthesizing the catalyst for producing hydrogen by electrolyzing seawater based on the metal ruthenium-doped copper nanowire composite structure of claim 1, wherein the reaction time of the second step is 0.5-2 h.
  6. 6. The method for synthesizing the catalyst for producing hydrogen by electrolyzing seawater based on the metal ruthenium doped copper nanowire composite structure of claim 1, wherein in the third step: the reaction time is 2-24 h; In the aqueous solution containing ruthenium salt, the concentration of the ruthenium salt is 5-60 mM; The ruthenium salt is ruthenium chloride.
  7. 7. The method for synthesizing the electrolytic seawater hydrogen production catalyst based on the metal ruthenium doped copper nanowire composite structure, which is characterized in that in the fourth step, the low-temperature heat treatment is performed in an argon atmosphere at a temperature of 150-400 ℃ and the treatment time is 1-5 h.
  8. 8. The method for synthesizing the catalyst for producing hydrogen by electrolyzing seawater based on the metal ruthenium doped copper nanowire composite structure of claim 1, wherein in the fifth step: The concentration of the potassium bicarbonate electrolyte is 0.25-1M; The constant current treatment has a current density of 300-800 mA cm -2 and a constant current treatment time of 3-24: 24 h.
  9. 9. The electrolytic seawater hydrogen production catalyst based on the metal ruthenium doped copper nanowire composite structure is characterized by comprising a foam copper current collector and a copper nanowire array grown on the surface of the foam copper current collector in situ, wherein the surface of the copper nanowire is uniformly loaded with metal ruthenium or ruthenium-based nanoclusters, and the electrolytic seawater hydrogen production catalyst comprises the following components in percentage by weight: the copper nanowire is formed by in-situ construction of foam copper through a chemical oxidation, thermal conversion and electrochemical reduction process; the ruthenium is distributed on the surface or near-surface layer of the copper nanowire in the form of metallic ruthenium or clusters; the catalyst for preparing hydrogen by electrolyzing seawater is of an integral self-supporting electrode structure and does not need a binder.
  10. 10. The catalyst for producing hydrogen by electrolyzing seawater based on the metal ruthenium doped copper nanowire composite structure of claim 9, wherein the catalyst for producing hydrogen by electrolyzing seawater is characterized in that: The diameter of the copper nanowire is 40-100 nm, and the length is more than 500-nm; the size of the clusters is 2-5 nm; The mass loading of ruthenium is 0.05-0.8 mg cm -2 .

Description

Electrolytic seawater hydrogen production catalyst based on metal ruthenium doped copper nanowire composite structure and synthesis method thereof Technical Field The invention belongs to the technical field of nano materials, electrochemical energy and catalysis, and relates to an electrolytic seawater hydrogen production catalyst based on a metal ruthenium doped copper nanowire composite structure and a synthesis method thereof. Background Hydrogen energy is considered to be one of the most promising new energy sources in the 21 st century due to its advantages such as cleanliness, high efficiency, safety and sustainability. The current industrial hydrogen production mainly comprises modes of electrolytic water hydrogen production, coal gasification hydrogen production, natural gas steam reforming hydrogen production and the like, wherein the electrolytic water hydrogen production has the advantages of clean process, high purity of hydrogen production and the like, and is an important technical route for realizing green hydrogen production. The catalyst adopted in the industrial water electrolysis hydrogen production at the present stage mainly comprises noble metals such as platinum, iridium and the like, has high cost and scarce resources, and severely restricts the large-scale application of the water electrolysis hydrogen production technology. Therefore, the development of the catalyst for producing hydrogen by electrolyzing water with low cost, high activity and high stability has important significance. Compared with the actual contradiction that fresh water resources are increasingly scarce, the seawater accounts for more than 97% of the total amount of the earth water resources, and the direct application of the seawater to the electrolytic hydrogen production is a necessary trend of the future hydrogen production technology development. However, the complex ionic composition in seawater and the near neutral electrolytic environment place higher demands on the activity and durability of the hydrogen evolving electrodes. The existing noble metal hydrogen evolution catalyst is easy to be inactivated or corroded in a seawater environment, has insufficient stability, and needs to be developed to be suitable for the seawater condition. The nanostructure material exhibits excellent performance in the field of electrocatalysis due to its high specific surface area, abundant active sites and controllable electronic structure. In particular, the one-dimensional metal nanowire structure has a continuous electron transmission path and good structural stability, and is beneficial to improving the dynamic performance of the electrocatalytic reaction. The copper material has rich resources and excellent conductivity, but has lower hydrogen evolution activity, and the electronic structure can be effectively regulated and controlled and the catalytic performance can be obviously improved by introducing a small amount of noble metal elements for doping or surface modification. Ruthenium is a relatively low-priced noble metal with excellent hydrogen evolution catalytic activity. Ruthenium atoms are introduced into the copper nanowire structure, so that the unification of high activity and high stability is realized while the cost is kept low. However, how to achieve uniform doping of ruthenium in copper nanowires and maintain stable structure and performance under the condition of seawater electrolysis is still a key technical problem to be solved. Disclosure of Invention Aiming at the problems of insufficient activity, poor stability, high cost and the like of the existing catalyst for producing hydrogen by electrolyzing seawater, the invention provides a catalyst for producing hydrogen by electrolyzing seawater based on a ruthenium-doped copper nanowire composite structure and a synthesis method thereof. The catalyst prepared by the invention is composed of a one-dimensional nano-structure network composed of copper nano-wires uniformly doped with ruthenium atoms, the diameter of each nano-wire is tens of nanometers, the length of each nano-wire is several micrometers, and the catalyst has continuous electron transmission channels and abundant surface active sites. The introduction of ruthenium effectively regulates and controls the electronic structure of the copper nanowire, obviously reduces the energy barrier of hydrogen evolution reaction, and simultaneously improves the corrosion resistance and long-term operation stability of the catalyst in a seawater environment. The synthesis method provided by the invention has the advantages of simple process, mild condition and strong controllability, and is suitable for large-scale preparation. The obtained catalyst has excellent hydrogen evolution catalytic activity and long-term stability in natural seawater close to neutral condition, and can realize stable hydrogen production under lower overpotential. In order to achieve the above purpose, the invention adopts