Progress in Design of Active Hydrogen Evolution Catalyst in MoS2

In the design of molybdenum disulfide (MoS2) in-plane high-activity hydrogen evolution catalyst, significant progress has been made recently. The team of Jianjun Liu, a researcher at the Shanghai Institute of Ceramics, Chinese Academy of Sciences, and Hongjin Fan, a professor at Nanyang Technological University in Singapore, collaborated on the design of two-dimensional chalcogenide molybdenum disulfide in-plane catalytic structures and made great progress.

the crystal structure of monolayer MoS2 image

Molybdenum disulfide (MoS2) is a promising candidate to replace Pt for electrocatalytic hydrogen evolution reaction (HER) due to its environmentally friendly and low-cost characteristics. Through theoretical calculations, researchers found that the catalytic adsorption site and the connected transition metal constitute a regional active center.

For the first time, the concept of regional electronegativity was proposed for catalyst design. Different transition metal atoms were selected to dope MoS2 surfaces to form different local structures. Through different TM-S chemical bond characteristics, the charge transferability of the molybdenum disulfide basal surface is adjusted to optimize the catalytic activity of hydrogen evolution. Related research results were published in Nature Communication recently, and received positive comments from international reviewers.

It is an important part to design a low-cost, highly active hydrogen evolution catalyst for efficient hydrogen production of establishing a hydrogen energy system. molybdenum disulfide owns the advantages of simple preparation, stable structure, and adjustable catalytic activity, so it is regarded as a very promising acidic electrolyzed hydrogen production catalyst. However, most of its high active sites are limited to limited boundaries, and how to realize the activation of molybdenum disulfide in-plane sites is the key to promote its practical application.

calculations to predict effect of local configurations to HER activity of MoS2 image

Therefore, the researchers worked closely based on theoretical calculations, experimental synthesis, and electrochemical characterization, and found that the triangular cobalt-doped molybdenum disulfide base surface with central sulfur vacancies exhibited excellent hydrogen evolution catalytic performance at a current density of 10 mA per square centimeter. The overpotential is only 75 mV. When the current density is increased or decreased by 10 times, the potential shift is 57 mV. It is one of the materials reported to have an excellent catalytic performance for two-dimensional MoS2 electrolysis of water to produce hydrogen.

At the same time, the team of Jianjun Liu systematically studied the regulation of the electrocatalytic activity of electronic states and cations of four transition metal elements with different doping defects and different boundary structures of MoS2 and proposed regional electronegativity as a catalytic activity descriptor to establish a coordination environment. The quantitative relationship between doped atom electronegativity, atomic radius, and regional electronegativity provides a theoretical basis for high activity screening. Related results were published in Material Chemistry edited by the American Chemical Society.

 

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