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CN-120272946-B - Cluster type self-healing hydroxy nickel iron oxide/nickel electrode and application thereof in hydrogen production by splitting saline-alkali water

CN120272946BCN 120272946 BCN120272946 BCN 120272946BCN-120272946-B

Abstract

The invention discloses a cluster self-healing ferronickel oxyhydroxide/nickel electrode and an application thereof in hydrogen production by splitting saline-alkali water, wherein the method comprises the steps of obtaining a metal cluster dispersion liquid by adopting a cyclic voltammetry in a potassium hydroxide solution electrolyte by taking foam metal as a working electrode under a three-electrode system; under a three-electrode system, using nickel iron/nickel MOF as a working electrode, using metal cluster dispersion liquid as an electrolyte, and adopting a cyclic voltammetry to obtain a target electrode, wherein the target electrode is used in a full reaction of hydrogen production by splitting saline-alkali water or splitting saline-alkali water in the electrolyte mixed by the metal cluster dispersion liquid and the saline-alkali water. The target electrode has higher activity and durability and good self-healing performance under the conditions of saline-alkali water and industrialized high current density (500 mA cm ‑2 ).

Inventors

  • CHEN SHENG
  • DUAN JINGJING
  • WANG HAIMING
  • HUANG QI

Assignees

  • 南京理工大学

Dates

Publication Date
20260512
Application Date
20240108

Claims (11)

  1. 1. The preparation method of the cluster self-healing ferronickel oxyhydroxide/nickel electrode is characterized by comprising the following steps of: In a three-electrode electrochemical system, foamed metal is used as a working electrode, hg/HgO is used as a reference electrode, a carbon material or noble metal material is used as a counter electrode, an alkaline solution is used as an electrolyte, and a cyclic voltammetry is adopted under the action of oxygen precipitation reaction potential at a certain stirring rate to obtain a metal cluster dispersion liquid, wherein the foamed metal is foamed nickel, foamed iron or foamed nickel iron; In a three-electrode electrochemical system, taking a nickel metal organic frame or a nickel iron metal organic frame as a working electrode, hg/HgO as a reference electrode, a carbon material or a noble metal material as a counter electrode, taking the metal cluster dispersion liquid obtained in the step one as an electrolyte, and adopting a cyclic voltammetry under the action of oxygen precipitation reaction potential at a certain stirring rate to obtain a cluster self-healing nickel iron oxyhydroxide electrode or a nickel electrode.
  2. 2. The method according to claim 1, wherein the ferronickel metal organic framework is obtained by dissolving 2-thiophenoic acid, nickel acetate and ferric nitrate in ethanol and then reacting with a foam nickel substrate in a closed environment at 150+ -10 ℃ for 0.5-16 h, wherein the ferric nitrate (ferric nitrate+nickel acetate) =0.05-0.20 in terms of mass ratio.
  3. 3. The method of claim 1, wherein the nickel metal organic framework is obtained by dissolving 2-thiophenecarboxylic acid and nickel acetate in ethanol, and then reacting with a foam nickel substrate in a closed environment at 150+ -10 ℃ for 12 h.
  4. 4. The method according to claim 1, wherein the alkaline solution is a KOH solution or a NaOH solution and the concentration thereof is 1 to 6 mol/L.
  5. 5. The method of claim 4, wherein the alkaline solution has a concentration of 4 to 6 mol/L.
  6. 6. The method of claim 1, wherein in step one, the cyclic voltammetry potential is 1.3-2.0V vs RHE, the cyclic voltammetry sweep number is 20-200, the stirring rate is 500-800 r/min, and in step two, the cyclic voltammetry potential is 0.9-1.7V vs RHE, the cyclic voltammetry sweep number is 20-200, and the stirring rate is 500-800 r/min.
  7. 7. A clustered self-healing iron nickel oxyhydroxide/nickel electrode prepared by the method of any one of claims 1-6.
  8. 8. The use of the clustered self-healing iron nickel oxyhydroxide/nickel electrode prepared by the method according to any one of claims 1-6 in a brine cracking oxygen-resolving reaction, wherein the metal cluster dispersion is mixed with brine to be decomposed to serve as an electrolyte.
  9. 9. The use according to claim 8, wherein in a three-electrode electrochemical system, the clustered self-healing ferronickel oxyhydroxide/nickel electrode is used as a working electrode, hg/HgO is used as a reference electrode, and a carbon material or noble metal material is used as a counter electrode for performing an alkaline water oxygen evolution reaction.
  10. 10. The use of the clustered self-healing iron nickel oxyhydroxide/nickel electrode prepared by the method according to any one of claims 1-6 in a full reaction of alkaline water splitting, wherein the metal cluster dispersion is mixed with the alkaline water to be split to serve as an electrolyte.
  11. 11. The use according to claim 10, wherein in a two-electrode electrochemical system, the clustered self-healing nickel iron oxyhydroxide/nickel electrode is used as an anode, and a platinum carbon electrode is used as a cathode, so as to carry out a full reaction of alkaline water splitting.

Description

Cluster type self-healing hydroxy nickel iron oxide/nickel electrode and application thereof in hydrogen production by splitting saline-alkali water Technical Field The invention relates to a cluster self-healing hydroxy nickel iron oxide/nickel electrode and application of hydrogen production by splitting saline-alkali water, belonging to the technical field of electrolytic water electrodes. Background The water splitting hydrogen production is a clean and green production mode, but the anodic oxygen precipitation reaction and the cathodic hydrogen precipitation reaction have serious thermodynamic delay, which restricts the activity, stability and energy efficiency of the electrolyzed water. To ameliorate this disadvantage, noble metal catalysts (e.g., iridium oxide, platinum, etc.) with high activity are commercially used for hydrogen production by electrolysis of water, but their rarity and high price severely limit the wide application of noble metal catalysts. In addition, most of the above materials require the use of fresh water or purified water as an electrolyte, which exacerbates the consumption of scarce fresh water resources and the additional investment costs. In contrast, a large amount of low-quality water such as seawater, inland brine and the like is widely distributed on the earth, and if the synthesized electrode can be directly used for hydrogen production by electrolysis of water or the low-quality water is simply treated, the electrode is very important in realizing sustainable utilization of clean energy and environmental protection. For this reason, related scholars have made some studies around sea water and put forward several common guidelines, but the above method is still controversial for the study of other low quality water. Further development of electrodes with high activity, durability and economy is needed, and intensive research on hydrogen production by cracking other low-quality water is carried out to promote high added value utilization of other low-quality water. The self-healing electrocatalyst can be automatically repaired at the damaged position by a special structural design or composition method, and the electrocatalyst can restore the electrocatalytic activity, and is expected to be a potential material for solving the problems. At present, the common self-healing catalytic electrode is mainly based on a buffer solution composed of metal ions such as Ni 2+、Co2+ and phosphate, carbonate or borate, and has a certain limitation in the aspect of system design. Disclosure of Invention The invention aims to provide a cluster self-healing ferronickel oxyhydroxide/nickel electrode and a preparation method thereof, which have stable hydrogen production performance by pyrolysis in saline-alkali water. The technical solution for realizing the purpose of the invention is as follows: The invention relates to a cluster self-healing ferronickel oxyhydroxide/nickel electrode and a preparation method thereof, comprising the following steps: In a three-electrode electrochemical system, foam metal is used as a working electrode, hg/HgO is used as a reference electrode, a carbon material or a noble metal material is used as a counter electrode, an alkaline solution is used as an electrolyte, and a cyclic voltammetry is adopted under the action of oxygen precipitation reaction potential at a certain stirring rate to obtain a metal cluster dispersion; In a three-electrode electrochemical system, taking a nickel metal organic frame or a nickel iron metal organic frame as a working electrode, hg/HgO as a reference electrode, a carbon material or a noble metal material as a counter electrode, taking the metal cluster dispersion liquid obtained in the step one as an electrolyte, and adopting a cyclic voltammetry under the action of oxygen precipitation reaction potential at a certain stirring rate to obtain the cluster self-healing nickel iron hydroxide/nickel electrode. Further, the ferronickel metal organic frame is obtained by dissolving 2-thiophenic acid, nickel acetate and ferric nitrate in ethanol, then reacting with a foam nickel substrate in a closed environment at 150+/-10 ℃ for 0.5-16h, wherein the ferric nitrate (ferric nitrate+nickel acetate) =0.05-0.20 in terms of mass ratio, and the nickel metal organic frame is obtained by dissolving 2-thiophenic acid and nickel acetate in ethanol, and then reacting with a foam nickel substrate in a closed environment at 150+/-10 ℃ for 12 h. In the first step, the alkaline solution is KOH solution or NaOH solution, the concentration of the alkaline solution is 1-6mol/L, preferably 4-6 mol/L, the foam metal is foam nickel, foam iron or foam nickel iron, the cyclic voltammetry potential is 1.3-2.0V (vs RHE), the cyclic voltammetry scanning turns are 20-200, and the stirring speed is 500-800r/min. Further, in the second step, the cyclic voltammetry potential is 0.9-1.7V (vs RHE), the number of cyclic voltammetry scanning turns is 20-200, and