Boosting Electrochemical Carbon Dioxide Reduction on Atomically Dispersed Nickel Catalyst

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Single-atom catalysts (SACs) with metal-nitrogen (M-N) sites are promising for electrochemical carbon dioxide reduction (ECO2R).
• Enhancing both activity and selectivity in ECO2R remains challenging due to reactant/intermediate interactions on catalytic sites.

Purpose of the Study:

• To develop a carbon-based nickel catalyst with both single-atom and cluster sites for improved ECO2R.
• To investigate the effect of Ni-N species dispersion on catalytic performance.
• To understand the synergistic effects between single-atom and cluster sites.

Main Methods:

• Ligand-mediated synthesis of carbon-based nickel catalysts (NiNx-T).
• Controlled pyrolysis conditions to tune Ni-N species dispersion.
• Electrochemical characterization to evaluate catalytic performance.

Main Results:

• NiNx-600 catalyst demonstrated high partial current density (61.85 mA cm⁻²) and turnover frequency (7,291 h⁻¹) at -1.2 V vs. RHE.
• Achieved nearly 100% selectivity towards carbon monoxide (CO) production.
• Exhibited good stability over 10 hours of continuous electrolysis.

Conclusions:

• The synergistic effect between pyrrolic-nitrogen coordinated Ni single-atom and cluster sites is crucial for high-performance ECO2R.
• Regulating the coordination environment and dispersion of transition metal sites significantly enhances ECO2R.
• The developed NiNx-600 catalyst represents a significant advancement in efficient CO2 conversion.