Satellite Pd Single-Atom Embraced AuPd Alloy Nanoclusters for Enhanced Hydrogen Evolution

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Hybrid active sites combining nanoclusters and single atoms (SAs) are crucial for advanced electrocatalyst design.
• Achieving synergistic effects between different catalytic components is key to enhancing electrocatalytic activity and durability.

Purpose of the Study:

• To develop a facile strategy for fabricating hybrid electrocatalysts with synergistic nanocluster and single-atom active sites.
• To investigate the structure-activity relationship of AuPd nanoclusters coupled with satellite Pd SAs for the hydrogen evolution reaction (HER).

Main Methods:

• A ligand-assisted pyrolysis strategy was employed using Au4Pd2(SC2H4Ph)8 nanoclusters with protected ligands.
• Controlled thermal treatment facilitated the formation of AuPd alloy nanoclusters surrounded by isolated Pd SAs.
• Electrochemical experiments and theoretical calculations were used to evaluate HER performance and understand the catalytic mechanism.

Main Results:

• The synthesized AuPd nanoclusters embraced by satellite Pd SAs demonstrated enhanced HER activity.
• The optimal catalyst (AuPdNCs/PdSAs-600) exhibited low overpotentials of 21 mV (acidic) and 38 mV (alkaline) at 10 mA cm-2.
• The mass activity and turnover frequency surpassed commercial Pd/C and Pt/C catalysts by an order of magnitude.

Conclusions:

• The hybrid active sites effectively optimize electronic structure and facilitate H2O adsorption/dissociation for improved HER.
• Ligand-protected nanoclusters synergized with SAs offer a promising pathway for designing high-performance electrocatalysts.
• This strategy provides valuable insights for future electrocatalyst development based on nanocluster-SA synergy.