Molybdenum carbide material and molybdenum carbide@molybdenum sulfide composite material, and preparation methods and applications thereof

Abstract

The invention discloses a molybdenum carbide material and a molybdenum carbide@molybdenum sulfide composite material, and preparation methods and applications thereof. The preparation method of the molybdenum carbide material comprises the following steps: adding a carbon source and a molybdenum source to a dispersion liquid, performing stirring for 6-12 h, drying the obtained mixture at 80-120 DEG C, grinding the dried mixture, and collecting the ground mixture to form a molybdenum carbide precursor; and performing temperature programming on the molybdenum carbide precursor to 400-900 DEG C from room temperature in an inert atmosphere, calcining the precursor at 400-900 DEG C for 1-3 h, grinding the calcined precursor, and collecting the ground calcined precursor to obtain molybdenum carbide. The molybdenum carbide is vulcanized at 160-400 DEG C by using a vulcanizing agent to obtain molybdenum carbide@molybdenum sulfide. The molybdenum carbide and the molybdenum carbide@molybdenum sulfide respectively have the morphology of a porous nanosheet structure, and the microstructure facilitates storage of an electrolyte and reduction of the charge transfer impedance and provides a lot of electrocatalytic activity sites; and the material and the composite material can be used as an HER electrocatalyst, have a high catalytic activity and a good stability, and are expected to replace aPt-based catalyst for electrolysis of water to produce hydrogen.

Description

technical field [0001] The invention relates to the technical field of preparation of molybdenum-based hydrogen evolution reaction electrocatalysts, in particular to molybdenum carbide materials, molybdenum carbide@molybdenum sulfide composite materials, preparation methods and applications. Background technique [0002] The rapid economic development has brought about an increasing demand for energy, and the environmental crisis has prompted people to pursue more sustainable and clean fuels, among which hydrogen largely meets the requirements for future energy. Currently, the production of industrial hydrogen relies heavily on methane reforming and coal gasification, which still rely on limited and non-renewable fossil fuels while generating large amounts of carbon dioxide. In addition, hydrogen production from water splitting using renewable energy sources, such as wind and solar energy, has become a research focus in recent years. The dissociation and desorption of hydro...

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Problems solved by technology

[0006] In view of the above-mentioned deficiencies in the prior art, the purpose of the present invention is to provide molybdenum carbide materials, molybdenum carbide@molybdenum sulfide composite materials and their preparation methods and applications, aiming to solve the problems of existing molybdenum-based HER electrocatalysts with small specific surface area and limited active sites. It leads to low catalytic activity and low catalytic efficiency of molybdenum sulfide materials due to their low conductivity, easy stacking of two-dimensional layered structures and active sites limited by the edges of bulk materials, which limit charge transport and kinetic rates.

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