Atomically Precise Dinuclear Site Active toward Electrocatalytic CO₂ Reduction.

Area of Science:

• Heterogeneous catalysis
• Nanomaterials science
• Electrochemistry

Background:

• Atomically precise catalysts offer enhanced performance and mechanistic insights.
• Dinuclear catalysts are promising for synergistic effects in chemical reactions.
• Understanding reaction mechanisms at the atomic level is crucial for catalyst design.

Purpose of the Study:

• To develop an atomically precise dinuclear nickel catalyst for electrochemical CO2 reduction.
• To elucidate the active dinuclear structure and synergy mechanism during the reaction.
• To demonstrate efficient carbon monoxide production via CO2 electroreduction.

Main Methods:

• Synthesis of atomically precise Ni2 sites anchored on N-doped carbon.
• Operando synchrotron X-ray absorption spectroscopy to identify dynamic structures.
• Theoretical simulations to understand reaction pathways and energy barriers.

Main Results:

• Identified a dynamic O-Ni2-N6 structure with enhanced Ni-Ni interaction under electrochemical CO2 reduction.
• Demonstrated that the O-Ni2-N6 structure significantly lowers the CO2 activation energy barrier.
• Achieved >94% Faradaic efficiency for carbon monoxide production.

Conclusions:

• A bottom-up strategy for synthesizing atomically precise dinuclear Ni2 catalysts was established.
• The active O-Ni2-N6 structure plays a critical role in efficient CO2 electroreduction.
• This work provides evidence for dinuclear sites as active species in catalytic reactions.