Hierarchical MoS2@MoP core-shell heterojunction electrocatalysts for efficient hydrogen evolution reaction over a...

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Developing efficient and cost-effective catalysts for the hydrogen evolution reaction (HER) is crucial for various applications.
• Existing catalysts often face limitations in terms of cost, stability, or performance across different pH conditions.

Purpose of the Study:

• To design and synthesize novel hierarchical flower-like MoS2@MoP core-shell heterojunctions (HF-MoSP) as a versatile catalyst for HER.
• To investigate the tunability of HF-MoSP properties, such as phosphidation degree and work function, by controlling synthesis parameters.
• To evaluate the electrocatalytic performance of HF-MoSP in acidic, alkaline, and neutral media.

Main Methods:

• Controlled phosphidation of hierarchical MoS2 flowers to create MoS2@MoP core-shell structures.
• Tuning phosphidation degree, P/S ratio, and work function by adjusting phosphidation temperature.
• Electrocatalytic testing for HER in 0.5 M H2SO4 and 1 M KOH, as well as neutral, weak acid, and weak alkaline conditions.

Main Results:

• Optimized HF-MoSP demonstrated excellent HER activity with low onset overpotentials (29 mV in acid, 42 mV in alkali) and sustained performance for 30 hours.
• The catalyst exhibited significant activity across a broad pH range, including neutral conditions.
• Performance is attributed to the synergistic effect between MoP shell and MoS2 core, high work function, and large surface area.

Conclusions:

• Hierarchical flower-like MoS2@MoP core-shell heterojunctions represent a promising low-cost, high-performance catalyst for the hydrogen evolution reaction.
• The study provides a novel approach for constructing core-shell heterojunctions for efficient electrocatalysis.
• Tunable properties and broad pH applicability make HF-MoSP suitable for diverse hydrogen production technologies.