Multi-Atom Sub-Nanometer Assemblies on Interpenetrating Multi-Chambered N/C Nanospheres.

Area of Science:

• Catalysis
• Materials Science
• Electrochemistry

Background:

• Atomically dispersed catalysts, including single-atom and dual-atom catalysts, are recognized for maximizing atom utilization and enhancing catalytic performance.
• Multi-atom catalysts (MACs) present unique advantages due to the collective effects of multiple metal atoms and tunable coordination environments, but their synthesis remains challenging.
• Precisely controlling the composition and arrangement of multiple metal atoms in MACs is crucial for their catalytic applications.

Purpose of the Study:

• To develop a versatile synthetic route for both mononuclear and heteronuclear multi-atom catalysts (MACs).
• To investigate the catalytic performance of synthesized MACs for the electrocatalytic reduction of carbon dioxide (CO2).
• To elucidate the synergistic effects between different metal atoms in MACs for improved CO2 conversion.

Main Methods:

• A soft-hard dual template strategy was employed for catalyst synthesis.
• The catalysts were stabilized on interpenetrating multi-chambered nitrogen/carbon (N/C) nanospheres.
• Electrocatalytic CO2 reduction was performed, and product selectivity (Faraday efficiency) and energy efficiency were measured.

Main Results:

• A novel synthesis route successfully produced mononuclear and heteronuclear MACs.
• The synthesized Ni/Cu-MAC demonstrated exceptional performance for electrocatalytic CO2 reduction, achieving a CO Faraday efficiency exceeding 99% at low potentials (-0.26 V to -0.56 V).
• A high cathode energy efficiency of over 75% was achieved at an industrial current density of 0.60 A cm-2.

Conclusions:

• The developed soft-hard dual template route is effective for synthesizing MACs.
• The Ni/Cu-MAC exhibits highly competitive performance for CO2-to-CO electrocatalysis.
• Synergistic interactions between Ni and Cu atoms are key to the enhanced catalytic conversion of CO2 to CO.