Atomic Vacancies Control of Pd-Based Catalysts for Enhanced Electrochemical Performance

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Structure-engineered palladium-based catalysts show promise for electrocatalysis, potentially matching or exceeding platinum-based catalysts.
• Developing efficient catalysts for oxygen reduction (ORR) and alcohol oxidation is crucial for energy conversion technologies.

Purpose of the Study:

• To synthesize and characterize novel anisotropic structure (AS) electrocatalysts based on PdCuCo with vacancy defects.
• To evaluate the electrochemical activity of these novel catalysts for oxygen reduction and alcohol oxidation reactions.

Main Methods:

• Synthesis of PdCuCo anisotropic structure (AS) electrocatalysts with abundant vacancy defects.
• Characterization using aberration-corrected transmission electron microscopy to verify structural defects.
• Electrochemical testing in acidic electrolyte to assess activity for oxygen reduction reaction (ORR) and alcohol oxidation.

Main Results:

• The synthesized vacancy-containing PdCuCo-AS (v-PdCuCo-AS) demonstrated excellent electrochemical activity.
• The mass activity of v-PdCuCo-AS for ORR was 0.18 A mg^-1 at 0.9 V vs RHE, significantly outperforming commercial Pd/C (15.55 times higher).
• Theoretical calculations indicated that promoted charge transfer due to polarized electronic structures and synergistic effects of defects and strain contribute to the enhanced activity.

Conclusions:

• The v-PdCuCo-AS exhibits superior electrocatalytic performance for ORR and alcohol oxidation in both acidic and alkaline media.
• The findings highlight the importance of vacancy defects and synergistic effects in designing high-performance electrocatalysts.
• This approach provides a viable strategy for developing other anisotropic structure catalysts with improved electrochemical properties.