Decoupling strain and ligand effects in ternary nanoparticles for improved ORR electrocatalysis

Area of Science:

• Materials Science
• Electrochemistry
• Computational Chemistry

Background:

• Pure platinum nanoparticles are benchmark catalysts for the oxygen reduction reaction (ORR).
• Developing more efficient and stable ORR catalysts is crucial for fuel cell technology.
• Understanding structure-activity relationships in nanoparticle catalysts is essential for rational design.

Purpose of the Study:

• To investigate the catalytic activity of ternary platinum-gold-metal (Pt-Au-M) nanoparticles for the ORR.
• To decouple and correlate strain and ligand effects in Pt-Au-M nanoparticles.
• To identify optimal 3d transition metals (M) for enhanced ORR performance and stability.

Main Methods:

• Density functional theory (DFT) calculations were employed to study Pt-Au-M nanoparticles.
• Strain and ligand effects were decoupled and benchmarked against extended Pt(111) surfaces.
• Computational screening of various 3d transition metals (Cr, Mn, Co, Cu, Zn) was performed.

Main Results:

• Ternary Pt-Au-M nanoparticles exhibit reduced OH adsorption energies compared to pure Pt.
• The core ternary metal tunes catalytic activity via strain effects.
• Pt-Au-M nanoparticles with mid to late 3d transition metals show enhanced activity and stability.

Conclusions:

• Ternary Pt-Au-M nanoparticles offer improved ORR activity and stability over pure Pt.
• Strain and ligand effects play crucial roles in tuning the catalytic performance.
• Computational predictions align with experimental findings for Pt-Au-Fe/Ni systems.