Efficient asymmetrical silicon-metal dimer electrocatalysts for the nitrogen reduction reaction

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• The Haber-Bosch method for ammonia synthesis is energy-intensive.
• Electrocatalytic nitrogen reduction reaction (ENRR) offers a sustainable alternative.
• Developing efficient ENRR catalysts remains a significant challenge.

Purpose of the Study:

• To design and investigate novel asymmetrical silicon-metal dimer catalysts for ENRR.
• To enhance nitrogen activation and reduction while suppressing hydrogen evolution.
• To explore the potential of these catalysts for efficient ammonia production.

Main Methods:

• Synthesis of asymmetrical silicon-metal dimer catalysts (SiM@C3N4) doped into g-C3N4 nanosheets with nitrogen vacancies.
• Electrochemical evaluation of catalysts for ENRR activity and selectivity.
• Analysis of catalyst properties, including hydrophobicity and stability.

Main Results:

• SiMo@C3N4 and SiRu@C3N4 catalysts exhibited high ENRR activity with low onset potentials (-0.20 V and -0.39 V, respectively).
• These catalysts effectively suppressed the competing hydrogen evolution reaction (HER).
• SiRu@C3N4 demonstrated significant hydrophobicity, beneficial for ammonia synthesis.

Conclusions:

• Asymmetrical silicon-metal dimer catalysts represent a promising strategy for efficient ENRR.
• The developed catalysts offer a sustainable route for ammonia production.
• The asymmetrical dimer approach can be extended to other electrocatalytic energy conversion reactions.