Inter-Metal Interaction with a Threshold Effect in NiCu Dual-Atom Catalysts for CO₂ Electroreduction

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Dual-atom catalysts (DACs) offer tunable active sites for multi-electron electrocatalytic reactions like CO2 reduction.
• Asymmetric DACs present structural complexity, hindering a full understanding of inter-metal interactions and catalytic mechanisms.

Purpose of the Study:

• To investigate the distance-dependent inter-metal interaction in NiCu DACs for CO2 reduction.
• To establish a structure-performance relationship for designing advanced DACs.

Main Methods:

• Density functional theory (DFT) computations.
• Aberration-corrected transmission electron microscopy (TEM).
• Synchrotron-based X-ray absorption fine structure (XAFS).
• Monte Carlo simulations.

Main Results:

• A structural model for NiCu DACs was proposed and validated.
• A distance threshold of approximately 5.3 Å between NiN4 and CuN4 moieties was identified as crucial for effective electronic regulation.
• This inter-metal distance significantly enhances CO2 reduction reaction (CRR) selectivity and activity.

Conclusions:

• Effective inter-metal interaction, governed by distance, is critical for optimizing DAC performance.
• A universal macro-descriptor correlating inter-metal distance with material features was developed for rational DAC design.
• This work bridges theoretical insights and experimental synthesis for advanced atomically dispersed catalysts.