Two-Dimensional Tantalum Carbo-Selenide for Hydrogen Evolution.

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Two-dimensional (2D) materials are crucial for advanced catalytic applications.
• Tantalum selenide carbide (Ta₂Se₂C) is a promising material for electrocatalysis.
• Efficient synthesis of high-quality 2D materials is essential for unlocking their potential.

Purpose of the Study:

• To synthesize two-dimensional tantalum selenide carbide (2D-Ta₂Se₂C) nanosheets.
• To evaluate the electrocatalytic activity of 2D-Ta₂Se₂C for the hydrogen evolution reaction (HER).
• To understand the structure-property relationships governing the enhanced HER performance.

Main Methods:

• Synthesis of multilayer Ta₂Se₂C via solid-state reaction of FeTa₂Se₂C followed by Fe etching.
• Exfoliation of multilayer Ta₂Se₂C into 2D-Ta₂Se₂C nanosheets using electrochemical lithiation and sonication.
• Electrocatalytic performance testing for HER, including overpotential and Tafel slope measurements.
• Characterization using transmission electron microscopy (TEM) to observe material morphology and defects.

Main Results:

• Successfully synthesized 2D-Ta₂Se₂C nanosheets with high surface area and increased vacancy density.
• 2D-Ta₂Se₂C demonstrated superior electrocatalytic activity for HER compared to multilayer Ta₂Se₂C and 2D-TaSe₂.
• Achieved an overpotential (η₁₀) of 264 mV and a Tafel slope of 91 mV·dec⁻¹ for 2D-Ta₂Se₂C.
• Measured an electrochemically active surface area (ECSA) of 17.61 m²/g.

Conclusions:

• The synthesized 2D-Ta₂Se₂C nanosheets exhibit excellent electrocatalytic performance for the hydrogen evolution reaction.
• The enhanced activity is attributed to the large surface area and increased density of vacancies in the 2D material.
• 2D-Ta₂Se₂C represents a promising non-precious metal catalyst for future electrochemical energy technologies.