Constructing Asymmetric Sn-Cu-C Interface via Defective Carbon Trapped Atomic Clusters for Efficient Neutral Nitrate...

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Multi-atom cluster (MACs) catalysts show promise for multi-electron reactions via cooperative active sites.
• Controllable synthesis and mechanistic understanding of MAC synergistic effects are significant challenges.

Purpose of the Study:

• To develop a defect engineering strategy for synthesizing bimetallic atomic clusters on defective graphene.
• To investigate the electrocatalytic mechanism and synergistic effects in SnCu-DG catalysts for nitrate reduction.

Main Methods:

• Defect engineering strategy utilizing carbon defect-mediated atomic trapping.
• Synthesis of bimetallic SnCu atomic clusters anchored at defective graphene (SnCu-DG).
• Electrocatalytic performance evaluation for nitrate reduction, X-ray adsorption spectra, and theoretical calculations.

Main Results:

• SnCu-DG catalyst achieved 99.5% NH3 Faradaic efficiency in neutral electrolyte.
• Record intrinsic activity of 2.61 × 10^-17 mmol h^-1 site_Cu^-1, outperforming counterparts.
• X-ray adsorption spectra and calculations revealed electron transfer and asymmetric charge polarization.

Conclusions:

• The dual modulation of electron transfer and charge polarization optimizes the catalytic microenvironment.
• Enhanced NO2- adsorption, accelerated water dissociation, and broken intermediate adsorption/hydrogenation scaling were observed.
• The defect engineering strategy provides a pathway for designing advanced MAC catalysts.