Core-bishell NiFe@NC@MoS₂ for boosting electrocatalytic activity towards ultra-efficient oxygen evolution reaction.

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Developing efficient oxygen evolution reaction (OER) catalysts is crucial for electrolytic water splitting.
• High activity and stability of OER catalysts remain a significant challenge.
• Existing catalysts often fall short in performance and durability.

Purpose of the Study:

• To design and synthesize novel core-bishell composite catalysts for enhanced OER performance.
• To investigate the catalytic activity and stability of NiFe@NC@MoS₂ composites.
• To understand the role of nitrogen-doped graphene (NC) and molybdenum disulphide (MoS₂) shells in OER.

Main Methods:

• Hydrothermal synthesis was employed to prepare NiFe@NC@MoS₂ core-bishell composites.
• Electrochemical performance was evaluated in 1 M KOH solution, measuring overpotential and Tafel slope.
• Density Functional Theory (DFT) analysis was used to confirm the catalytic mechanism and active sites.

Main Results:

• The NiFe@NC@MoS₂ composite exhibited excellent OER performance with an overpotential of 288 mV and a Tafel slope of 53.2 mV·dec^-1 at 10 mA·cm^-2.
• Performance surpassed that of commercial RuO₂.
• The NC and MoS₂ shells provided abundant edge active sites, enhancing OOH* adsorption and lowering overpotential.

Conclusions:

• The NiFe@NC@MoS₂ core-bishell composite demonstrates superior OER activity and stability.
• The synergistic effect of NC and MoS₂ shells significantly boosts catalytic performance.
• This study presents a promising strategy for developing advanced electrocatalysts for water splitting.