Hydroxyl Spillover Activated from the Strongly Coupled Ru@Mn₃O₄ Heterostructure to Promote Alkaline Hydrogen...

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Alkaline hydrogen evolution reaction (HER) is vital for sustainable hydrogen production.
• Developing efficient catalysts with superior water dissociation and facile OH* desorption remains a challenge.

Purpose of the Study:

• To design and synthesize a novel heterostructure catalyst for enhanced alkaline HER.
• To investigate the mechanism of water dissociation, OH* desorption, and H adsorption on the catalyst.

Main Methods:

• Synthesis of a strongly coupled Ru@Mn3O4 heterostructure with Ru clusters decorated on Mn3O4 via Ru-O-Mn bonds.
• Electrochemical characterization of the catalyst's HER performance, including overpotential and Tafel slope.
• Analysis of catalytic activity using mass activity (MA) and turnover frequency (TOF) compared to commercial Pt/C.

Main Results:

• The Ru@Mn3O4 catalyst exhibits excellent HER performance with a low overpotential of 17 mV and a Tafel slope of 30 mV dec-1.
• The heterostructure facilitates superior water dissociation and facile OH* desorption via a hydroxyl spillover effect.
• Ru@Mn3O4 shows significantly higher mass activity (11-fold) and turnover frequency (8-fold) compared to Pt/C.

Conclusions:

• The Ru@Mn3O4 heterostructure represents a highly effective catalyst for alkaline HER.
• The study provides a new strategy for designing high-performance HER catalysts by leveraging hydroxyl spillover effects.
• This work offers insights into the mechanism of alkaline HER catalysis.