CN-121976238-A - Molybdenum-cobalt-based composite sulfide electrocatalyst and preparation method and application thereof

Abstract

The invention discloses a preparation method of a MoS 2 /CoS/CoS 2 compound electrocatalyst and application thereof in an electrolytic water Oxygen Evolution Reaction (OER), and belongs to the technical field of catalysts. Under the condition of room temperature, cobalt acetate tetrahydrate, sodium molybdate dihydrate and thioacetamide are dissolved in a mixed solution of deionized water and propionic acid, uniformly stirred and then subjected to hydrothermal reaction for 18 hours, and then the target product MoS 2 /CoS/CoS 2 is obtained through centrifugation, cleaning and drying steps. The preparation method has the advantages of simple process, low cost, low price of the required raw materials and easy acquisition, and the obtained product has good crystallinity. As an electrolytic water oxygen evolution reaction catalyst, the MoS 2 /CoS/CoS 2 material has an overpotential of 262 mV at a current density of 10 mA cm −2 and shows an electrocatalytic performance superior to that of a commercial RuO 2 catalyst. Meanwhile, the catalyst has excellent activity and stability in oxygen evolution reaction and has wide application prospect.

Inventors

• HUANG XING
• YANG RUOLAN
• ZHU LI
• CHEN DECHAO

Assignees

• 福州大学

Dates

Publication Date

20260505

Application Date

20260204

Claims (4)

1. 1. The preparation method of the molybdenum-cobalt-based composite sulfide electrocatalyst is characterized by comprising the following steps of: (1) Mixing deionized water and propionic acid, sequentially adding cobalt acetate, sodium molybdate and thioacetamide, and stirring at room temperature for 30 min; (2) And carrying out hydrothermal reaction at 200 ℃ for 18 hours, naturally cooling to room temperature, centrifuging, washing and filtering with deionized water and absolute ethyl alcohol, and carrying out vacuum drying at 60 ℃ for 12 hours to obtain the molybdenum-cobalt-based composite sulfide electrocatalyst MoS 2 /CoS/CoS 2 .
2. 2. The method of claim 1, wherein the molar ratio of cobalt acetate, sodium molybdate and thioacetamide is 2-6:1:1.
3. 3. A molybdenum cobalt-based composite sulfide electrocatalyst produced according to the method of any one of claims 1 to 2.
4. 4. Use of a molybdenum cobalt-based complex sulfide electrocatalyst prepared according to any one of claims 1 to 2 in an electrolyzed water oxygen evolution reaction.

Description

Molybdenum-cobalt-based composite sulfide electrocatalyst and preparation method and application thereof Technical Field The invention belongs to the technical field of catalysts, and particularly relates to a preparation method of a molybdenum-cobalt-based composite sulfide (MoS 2/CoS/CoS2) electrocatalyst and application of the electrocatalyst in an electrolytic water Oxygen Evolution Reaction (OER). Background At present, the energy structure of China still takes non-renewable traditional fossil energy as a main source, and a large amount of greenhouse gases can be generated in the using process, so that serious environmental problems are caused. Although clean energy sources such as solar energy, geothermal energy and biomass energy have sustainable development potential, the large-scale industrial application of the solar energy, geothermal energy and biomass energy is limited by factors such as territory and intermittence. In contrast, hydrogen energy is widely available, clean and efficient, has a high calorific value, and is pollution-free in use, and is widely recognized as an ideal alternative to fossil energy. The hydrogen production by water electrolysis has the advantages of green pollution-free property, high hydrogen purity and the like, and is one of hydrogen energy preparation ways with the most development prospect. In the process of water electrolysis, oxygen evolution reaction is a key half reaction in the electrolyzed water, the process involves multi-step proton-electron transfer, and the dynamics are extremely complex. At present, noble metals and their oxides (such as Ir, ru and their compounds) which are commonly used commercially, although exhibiting excellent catalytic properties, severely restrict their large-scale application due to the scarce reserves, high cost and limited stability. Therefore, it is of great importance to develop OER electrocatalysts with high activity and high stability under alkaline conditions. The transition metal compound represented by cobalt-based sulfide and molybdenum-based sulfide has the advantages of abundant resources, simple and convenient preparation, low cost and the like, and becomes a potential substitute material. The cobalt-based sulfide has various structures and is easy to regulate and control, cobalt can easily form bimetallic sulfide with other metals (such as Fe, ni, cu, mo and the like), and the recombination between the materials can effectively regulate and control the electronic structure of the materials. The molybdenum-based sulfide has a two-dimensional layered structure and a larger surface area, has excellent catalysis promoting effect, and can be used as a cobalt-based sulfide accelerator. Based on the structure, two cobalt-based sulfides and molybdenum-based sulfides with different functions are integrated together to construct a heterostructure, so that the structure between electrons can be regulated, more active sites can be exposed under the synergistic action of the cobalt-based sulfide and the molybdenum-based sulfide, the stability of the structure is enhanced, and the OER catalytic performance of the structure is remarkably improved. Disclosure of Invention The invention aims to provide a preparation method of a molybdenum-cobalt-based composite sulfide (MoS 2/CoS/CoS2) electrocatalyst and application thereof in an electrolytic water Oxygen Evolution Reaction (OER), and the preparation method is simple and convenient and has excellent catalytic performance. In order to achieve the above purpose, the invention adopts the following technical scheme: The preparation method of the molybdenum-cobalt-based composite sulfide (MoS 2/CoS/CoS2) electrocatalyst comprises the following steps: (1) Mixing deionized water and propionic acid, sequentially adding cobalt acetate, sodium molybdate and thioacetamide, and stirring at room temperature for 30 min; (2) And carrying out hydrothermal reaction at 200 ℃ for 18 hours, naturally cooling to room temperature, centrifuging, washing and filtering with deionized water and absolute ethyl alcohol, and carrying out vacuum drying at 60 ℃ for 12 hours to obtain the molybdenum-cobalt-based composite sulfide electrocatalyst MoS 2/CoS/CoS2. Further, the molar ratio of the cobalt acetate to the sodium molybdate to the thioacetamide is 2-6:1:1. The molybdenum cobalt-based composite sulfide (MoS 2/CoS/CoS2) electrocatalyst prepared by the method is applied to the electrolytic water oxygen evolution reaction. The electrocatalyst has excellent OER performance in 1M KOH electrolyte. The electrocatalytic oxygen evolution reaction is carried out in an alkaline solution by using a three-electrode system, wherein the alkaline solution is 1M KOH, the three-electrode system comprises a counter electrode, a reference electrode and a working electrode, the working electrode is a carbon cloth electrode, the catalyst loading amount is 0.5 mg/cm 2, the catalytic oxygen evolution reaction is a reaction proces