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CN-120844145-B - Sulfur-doped keggin type molybdenum polyacid and nickel sulfide heterojunction composite catalyst and preparation method and application thereof

CN120844145BCN 120844145 BCN120844145 BCN 120844145BCN-120844145-B

Abstract

The invention provides a sulfur-doped keggin type molybdenum polyacid and nickel sulfide heterojunction composite catalyst, and a preparation method and application thereof. The heterojunction composite catalyst is formed by compounding sulfur-doped keggin type molybdenum polyacid and nickel sulfide, and the heterostructure of the heterojunction composite catalyst is formed by MoS 2 and NiS. According to the invention, the nickel source is modified and synchronously vulcanized by using the keggin type molybdenum polyacid (HPMo 9 O 34 ] 8‑ ) as a multi-metal oxygen cluster skeleton, so that the synthesis of the heterojunction composite catalyst of the sulfur-doped keggin type molybdenum polyacid and nickel sulfide is realized, the heterojunction composite catalyst has excellent electrocatalytic performance and excellent electrochemical stability, and in an oxygen evolution reaction, the heterojunction composite catalyst shows lower overpotential, lower Tafil slope and excellent long-time operation stability, and a practical strategy is provided for developing OER materials with high performance, low cost and corrosion resistance.

Inventors

  • ZHANG JIANGWEI
  • Zhu Houen
  • WU LIMIN
  • ZHAO DONGYUAN

Assignees

  • 内蒙古大学
  • 内蒙古蒙威氢能科技有限公司

Dates

Publication Date
20260508
Application Date
20250923

Claims (8)

  1. 1. The preparation method of the heterojunction composite catalyst of sulfur-doped keggin type molybdenum polyacid and nickel sulfide is characterized by comprising the following steps: mixing a nickel source solution, thiourea and keggin type molybdenum polyacid to obtain a mixture solution; Placing a metal substrate in the mixture solution for growth reaction, and drying to obtain a heterojunction composite catalyst of sulfur-doped keggin type molybdenum polyacid and nickel sulfide grown in situ on the surface of the metal substrate, wherein the temperature for the growth reaction is 180-230 ℃ and the time is 20-30h; Wherein the keggin type molybdenum polyacid anion chemical formula is [ HPMo 9 O 34 ] 8- .
  2. 2. The preparation method of the heterojunction composite catalyst of sulfur-doped keggin type molybdenum polyacid and nickel sulfide, which is characterized in that the mass ratio of nickel source, thiourea and keggin type molybdenum polyacid in the nickel source solution is (10-15): 6-10): 8-12.
  3. 3. The preparation method of the heterojunction composite catalyst of sulfur-doped keggin type molybdenum polyacid and nickel sulfide, which is characterized in that the mass concentration of a nickel source solution is 10-15mg/mL, and the nickel source in the nickel source solution comprises nickel nitrate hexahydrate; And/or the metal substrate comprises any one of foam nickel iron and foam nickel.
  4. 4. The heterojunction composite catalyst of sulfur-doped keggin type molybdenum polyacid and nickel sulfide prepared by the preparation method according to any one of claims 1 to 3, wherein the heterojunction composite catalyst is formed by compounding a keggin type molybdenum polyacid doped with sulfur and nickel sulfide; The heterostructure of the heterojunction composite catalyst is formed by MoS 2 and NiS.
  5. 5. The sulfur-doped keggin-type molybdenum polyacid and nickel sulfide heterojunction composite catalyst of claim 4, wherein the heterostructure of the heterojunction composite catalyst is composed of a (002) crystal plane containing MoS 2 , a (101) crystal plane of NiS, and a (300) crystal plane of NiS.
  6. 6. The sulfur-doped keggin-type molybdenum polyacid and nickel sulfide heterojunction composite catalyst of claim 4, wherein the morphology of the sulfur-doped keggin-type molybdenum polyacid and nickel sulfide heterojunction composite catalyst is a composite structure comprising a synaptic structure and a nano-sheet structure.
  7. 7. An electrode is characterized by comprising a metal substrate and a heterojunction composite catalyst of sulfur-doped keggin type molybdenum polyacid and nickel sulfide which are grown on the surface of the metal substrate in situ; wherein the heterojunction composite catalyst of the sulfur-doped keggin type molybdenum polyacid and nickel sulfide is the heterojunction composite catalyst of the sulfur-doped keggin type molybdenum polyacid and nickel sulfide of any one of claims 4-6; the metal substrate comprises any one of foam nickel iron and foam nickel.
  8. 8. Use of the heterojunction composite catalyst of sulfur-doped keggin type molybdenum polyacid and nickel sulfide as defined in any one of claims 4 to 6 or the electrode as defined in claim 7 for alkaline electrolyzed water oxygen evolution reaction or electrolyzed seawater oxygen evolution reaction.

Description

Sulfur-doped keggin type molybdenum polyacid and nickel sulfide heterojunction composite catalyst and preparation method and application thereof Technical Field The invention relates to the technical field of catalysts, in particular to a heterojunction composite catalyst of sulfur-doped keggin type molybdenum polyacid and nickel sulfide, and a preparation method and application thereof. Background The hydrogen production by water electrolysis refers to a process of electrolyzing water to produce hydrogen and oxygen under a certain external voltage, and the process is free of carbon dioxide (CO 2) emission, green and pollution, and is considered to be an effective way for producing, storing and using renewable energy sources in the future. The electrolyzed water consists of two half reactions, cathodic Hydrogen Evolution (HER) and anodic Oxygen Evolution (OER), respectively. However, the reaction energy barrier of the electrolyzed water is high, and the catalyst is required to reduce the overpotential in the reaction process of the electrolyzed water so as to improve the hydrogen production efficiency of the electrolyzed water. At present, the traditional catalyst is mainly a noble metal-based catalyst, such as a platinum (Pt) based catalyst, iridium oxide (IrO 2), ruthenium oxide (RuO 2) and the like, and the noble metal-based catalyst can effectively improve the hydrogen production efficiency of water electrolysis, but the factors such as scarcity, high price and the like seriously prevent the large-scale application of the noble metal-based catalyst. In addition, as the problem of shortage of fresh water resources is increasingly prominent, seawater (which accounts for more than 97% of the global water reserves) becomes an ideal raw material for producing hydrogen by water electrolysis due to the abundance of the reserves. However, seawater has a complex composition and contains various anions and cations (such as Na +、K+、Ca2+、Cl-、SO42-, etc.), wherein the existence of Cl - can severely corrode the catalyst, so that the electrochemical stability of the catalyst is reduced. Therefore, a non-noble metal-based catalyst having low development cost and high electrochemical stability is a problem to be solved. Disclosure of Invention The heterojunction composite catalyst of sulfur-doped keggin type molybdenum polyacid and nickel sulfide has excellent electrocatalytic performance and electrochemical stability, is applied to alkaline electrolysis water oxygen evolution reaction or electrolysis sea water oxygen evolution reaction, and has lower overpotential, lower Tafil slope and excellent long-time operation stability, and the preparation raw material cost of the heterojunction composite catalyst is low, the preparation process is simple, and a practical strategy is provided for developing OER materials with high performance, low cost and corrosion resistance. The invention also provides a preparation method of the heterojunction composite catalyst of the sulfur-doped keggin type molybdenum polyacid and nickel sulfide, the heterojunction composite catalyst with excellent electrocatalytic performance and excellent electrochemical stability can be prepared by the method, the heterojunction composite catalyst is applied to alkaline electrolysis water oxygen evolution reaction or electrolysis sea water oxygen evolution reaction, the heterojunction composite catalyst shows lower overpotential, lower Tafil slope and excellent long-time operation stability, the method is simple in process, easy to operate, free of three wastes in the preparation process, environment-friendly and beneficial to realizing industrial production. The invention also provides an electrode which comprises a metal substrate and the heterojunction composite catalyst of the sulfur-doped keggin type molybdenum polyacid and nickel sulfide, wherein the heterojunction composite catalyst grows on the surface of the metal substrate in situ, and the electrode shows lower overpotential, lower Tafil slope and excellent long-time operation stability in an oxygen evolution reaction. The invention also provides an application of the electrode, wherein the electrode is used for alkaline electrolysis water oxygen evolution reaction or electrolysis sea water oxygen evolution reaction. The inventors have studied that an electrode made of a metal substrate and the above-described heterojunction composite catalyst of sulfur-doped keggin-type molybdenum polyacid and nickel sulfide grown in situ on the surface of the metal substrate is subjected to an oxygen evolution reaction in a 1M KOH solution or in simulated seawater (1.0M KOH+0.5M KCl solution), which exhibits a lower overpotential, a lower tafel slope, and excellent long-term running stability. The invention provides a heterojunction composite catalyst of sulfur-doped keggin type molybdenum polyacid and nickel sulfide, which is formed by compounding the keggin type molybdenum polyacid doped with sulfur and t