Carbon/molybdenum disulfide-nitrogen-rich molybdenum nitride composite material, preparation and electro-catalytic hydrogen evolution application thereof

Abstract

The invention discloses a preparation method of a carbon / molybdenum disulfide-nitrogen-rich molybdenum nitride composite electrochemical catalyst material. The method comprises the following steps: introducing a MoO3 nanowire in a polymerization process of a pyrrole monomer, and preparing MoO3 nanowire with the surface coated with polypyrrole; under a solvothermal reaction condition, promoting the inner core MoO3 nanowire to be dissolved, and reacting with thiourea to vertically grow a molybdenum disulfide nanosheet vertically on the surface of the hollow polypyrrole nanotube; and then carrying out thermal nitridation, wherein the hollow polypyrrole nanotube is converted into a hollow carbon nanotube, and the MoS2 nanosheet is converted into MoS2-Mo5N6, so that the Mott-Schottky heterojunction composite material growing on the surface of the hollow carbon nano tube in situ is obtained. According to the invention, the composite electrochemical catalyst material obtained by the invention can effectively promote the electronic interaction between interfaces, improve the kinetic rate of catalytic hydrogen evolution reaction and effectively improve the catalytic activity of a MoS2-based plane; and the preparation method is simple, convenient to operate and suitable for popularization and application.

Description

technical field [0001] The invention belongs to the technical field of functional materials, and specifically relates to a carbon / molybdenum disulfide-nitrogen-rich molybdenum nitride composite electrochemical catalyst material and its preparation and application of electrocatalytic hydrogen evolution. Background technique [0002] Hydrogen fuel is considered to be the cleanest renewable energy source and a major substitute for fossil fuels in future energy supply. So far, in the commonly used hydrogen production pathways, the use of electrochemical catalytic methods to decompose water for hydrogen production has the advantages of simplicity, high efficiency, and high purity of hydrogen production. At the same time, this method can also be well combined with renewable energy to achieve efficient storage and conversion of clean energy. However, the large overpotential in electrocatalytic hydrogen production leads to high energy consumption and low efficiency. In order to re...

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Problems solved by technology

[0003]Molybdenum disulfide, as a transition metal compound with a layered structure, has potential applications in the fields of electrocatalysis, electronics, and energy harvesting due to its edge-exposed active sites Huge potential, but because its active sites are mostly distributed at the edge, its basal plane reaction activity is inert, and its conductivity is low, and its catalytic performance will be poor at that time; it is usually necessary to further adopt induced phase transition, introduction of heteroatoms, and structural heterogeneity Modification of molybdenum disulfide-based planes by interface and other methods to obtain more excellent catalytic performance

CN201810117506.9 discloses a method for preparing metallic transition metal sulfide nanosheet arrays by chemical vapor deposition; using porous gold as a growth substrate, elemental sulfur and transition metal chlorides as precursors, elemental sulfur, transition metal chloride After the sulfide and porous gold are heated to different temperatures and held for a certain period of time, the corresponding catalyst products are obtained; however, the preparation cost of this method is too high and the overpotential of the single sulfide catalyst is high, and the catalytic efficiency is insufficient.

CN202110140903.X discloses a method for preparing nitrogen-doped spherical graphene-supported flake-shaped molybdenum disulfide catalyst. This method also has the problem of low catalytic hydrogen evolution efficiency, and cannot adapt to industrial-level high-current-density electrolysis of water for hydrogen production.

According to the above reports, MoS2 still has problems such as low catalytic hydrogen production efficiency and high catalytic energy consumption, and it is not suitable for industrial-level high current density electrolysis of water to produce hydrogen.

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