Synergistic Effects and Activity Descriptors in Double-Atom Catalysts for Electrochemical CO₂ Reduction: A...

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Electrochemical CO2 reduction (CO2RR) is crucial for sustainable energy and carbon mitigation.
• Double-atom catalysts (DACs) on N-doped graphene offer a novel approach to CO2RR.

Purpose of the Study:

• Systematically investigate 55 homogeneous and heterogeneous diatomic catalysts on N-doped graphene.
• Identify high-performance DACs for various CO2RR products.
• Provide a design framework for advanced graphene-based electrocatalysts.

Main Methods:

• Density Functional Theory (DFT) calculations.
• Screening of 10 transition metals in diatomic configurations (M-M and M1-M2).
• Analysis of descriptors like d-band center, Bader charge, and Gibbs free energy.

Main Results:

• Identified top DACs for CO/CH3OH (Cu-Cr, Ni-Pd, Pd-Pd), HCOOH (*COOH pathway: Co-Co, Fe-Fe, Cu-Cr, Co-Cu; *OCHO pathway: Co-Ni, Cu-Cu, Co-Pd), and CH4 (*CO pathway: Cu-V, Cr-Cr, V-Pd; *HCOOH pathway: Fe-Pd, Mn-Cu, Cu-Cr, V-Pd).
• Demonstrated synergistic effects, optimal intermediate adsorption, and low energy barriers.
• Correlated catalyst performance with electronic descriptors.

Conclusions:

• Established structure-activity relationships for DACs in CO2RR.
• Highlighted the potential of specific DACs for selective product generation.
• Provided a computational framework for designing efficient graphene-based electrocatalysts for CO2 conversion.