A Supported Pd₂ Dual-Atom Site Catalyst for Efficient Electrochemical CO₂ Reduction.

Area of Science:

• Heterogeneous catalysis
• Electrocatalysis
• Materials science

Background:

• Dual-atom site catalysts (DACs) leverage synergistic effects between adjacent metal atoms.
• DACs combine the high atomic utilization efficiency and selectivity of single-atom site catalysts (SACs) with enhanced activity.
• The electrochemical CO2 reduction reaction (CO2 RR) is crucial for carbon utilization and renewable energy storage.

Purpose of the Study:

• To synthesize and evaluate a supported palladium-2 (Pd2) dual-atom site catalyst (DAC) for the electrochemical CO2 reduction reaction (CO2 RR).
• To investigate the catalytic performance and stability of the Pd2 DAC compared to single-atom catalysts.
• To elucidate the underlying mechanism for the enhanced catalytic activity of the Pd2 DAC.

Main Methods:

• Synthesis of a supported Pd2 DAC.
• Electrochemical CO2 reduction reaction (CO2 RR) testing.
• Density Functional Theory (DFT) calculations.

Main Results:

• The synthesized Pd2 DAC exhibited excellent CO2 RR performance, achieving 98.2% CO faradic efficiency at -0.85 V vs. RHE.
• The Pd2 DAC significantly outperformed Pd single-atom site catalysts (Pd1 SAC) in CO2 RR.
• The catalyst demonstrated long-term operational stability.
• DFT calculations indicated that electron transfer between adjacent Pd atoms in the Pd2 DAC is responsible for its superior activity.

Conclusions:

• The Pd2 DAC shows remarkable potential for efficient and selective electrochemical CO2 to CO conversion.
• The synergistic effect in DACs, specifically electron transfer between metal centers, is key to enhancing catalytic performance.
• This work establishes Pd2 DACs as a promising platform for advanced electrocatalysis.