Activated MoS₂ by Constructing Single Atomic Cation Vacancies for Accelerated Hydrogen Evolution Reaction

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Regulating the electronic structure of molybdenum disulfide (MoS2) via cation vacancies is key to enhancing its catalytic properties.
• Developing efficient and stable catalysts for the hydrogen evolution reaction (HER) is crucial for clean energy technologies.

Purpose of the Study:

• To synthesize a novel MoS2-based composite with abundant single atomic Mo cation vacancies.
• To investigate the catalytic performance of the composite for the hydrogen evolution reaction (HER).
• To explore the role of electronic structure modulation in enhancing catalytic activity.

Main Methods:

• Synthesis of NiCoPBA-MoS2-VMo composite by loading Ni-MoS2 with nickel-cobalt-Prussian blue analogues.
• Post-synthesis phosphation to improve conductivity.
• Electrochemical characterization and theoretical calculations (e.g., density functional theory) to analyze electronic structure and catalytic mechanisms.

Main Results:

• The NiCoP-MoS2-VMo catalyst exhibits abundant single atomic Mo cation vacancies and improved conductivity.
• Spontaneous electron transfer from NiCoP to MoS2-VMo enhances OH* adsorption, while Mo vacancies optimize H* adsorption.
• The catalyst achieves a low overpotential of 67 mV at 10 mA cm-2 for HER with excellent long-term stability (>20 h).

Conclusions:

• The engineered MoS2-VMo with NiCoP demonstrates superior HER performance due to synergistic electronic structure modulation.
• This work presents an effective strategy for designing high-performance electrocatalysts by introducing single atomic cation vacancies.
• The developed catalyst offers a promising pathway for inexpensive and efficient hydrogen production.