Synthesis of Two-Dimensional High-Entropy Transition Metal Dichalcogenide Single Crystals

Area of Science:

• Materials Science
• Nanotechnology
• Catalysis

Background:

• Two-dimensional (2D) high-entropy transition metal dichalcogenides (HETMDs) are of significant interest for advanced devices.
• Controlled synthesis of 2D HETMDs is challenging due to variations in precursor properties and product formation energies.

Purpose of the Study:

• To develop a controlled synthesis method for 2D HETMD single crystals.
• To explore the catalytic properties of the synthesized HETMDs for the hydrogen evolution reaction (HER).

Main Methods:

• A liquid-phase reaction system was employed for uniform and simultaneous feeding of metal elements.
• Rapid codeposition of precursors was utilized to facilitate high-entropy product formation and prevent phase separation.

Main Results:

• A 0.92 nm thick 2D HETMD single crystal was successfully synthesized.
• The method demonstrated versatility in producing various HETMDs, including quinary, hexahydroxy, and multichalcogenide compositions.
• The synthesized 2D HETMD exhibited excellent HER catalytic activity with an overpotential of 84 mV at 10 mA cm⁻², outperforming pristine MoS₂.

Conclusions:

• The liquid-phase synthesis strategy provides precise control over element selectivity and properties of 2D HETMD single crystals.
• This approach enables the design of novel HETMD materials for diverse advanced applications, particularly in catalysis.