Atomic Au₃Cu Palisade Interlayer in Core@Shell Nanostructures for Efficient Kirkendall Effect Mediation.

Area of Science:

• Materials Science
• Nanotechnology
• Catalysis

Background:

• Plasmonic copper@semiconductor heteronanocrystals (HNCs) offer promising properties for catalysis.
• The nanoscale Kirkendall effect often impedes the synthesis of solid HNC structures.

Purpose of the Study:

• To develop a method for synthesizing solid Cu@semiconductor HNCs by mitigating the Kirkendall effect.
• To investigate the role of an atomically thin gold-copper interlayer in controlling material diffusion and lattice mismatch.

Main Methods:

• Utilized an atomically thin Au3Cu palisade interlayer for topological synthesis.
• Employed successive cation exchange to create Cu@Au3Cu@Ag2S and Cu@Au3Cu@CdS core-shell HNCs.
• Conducted experimental and theoretical investigations to study Cu atom diffusion kinetics.

Main Results:

• Successfully synthesized solid Cu@Au3Cu@CdS HNCs with exceptional crystallinity and organized heterointerfaces.
• The Au3Cu interlayer effectively modulated Cu diffusion and alleviated lattice mismatch between Cu and Ag/CdS.
• Demonstrated efficient plasmon-induced hot electron injection from the Cu@Au3Cu core into the CdS shell.

Conclusions:

• The developed method enables the synthesis of advanced plasmonic HNCs by controlling the Kirkendall effect.
• Cu@Au3Cu@CdS HNCs exhibit high activity and selectivity for photocatalytic CO2 reduction to CO.
• Atomically thin interlayers are crucial for designing functional nanomaterials with controlled interfaces.