Solution-Grown Dendritic Pt-Based Ternary Nanostructures for Enhanced Oxygen Reduction Reaction Functionality

Area of Science:

• Materials Science
• Nanotechnology
• Catalysis

Background:

• Anisotropic nanoalloys with branched structures are promising high-performance materials.
• Existing synthesis methods for branched nanostructures often rely on complex seed-growth processes.

Purpose of the Study:

• To develop a simple, fast, and scalable synthesis for hyperbranched platinum (Pt) nanoalloys.
• To investigate the effect of alloying with transition metals (Ni, Co, Fe) on morphology and catalytic activity.
• To evaluate the performance of the synthesized nanoalloys in the oxygen reduction reaction (ORR).

Main Methods:

• A one-pot solution-phase thermal reduction strategy was employed.
• Platinum was alloyed with varying ratios of Ni, Co, and Fe.
• Morphological characterization of the resulting nanoalloys was performed.
• Electrocatalytic activity towards the oxygen reduction reaction (ORR) was assessed.

Main Results:

• Hyperbranched Pt nanoalloys with good dispersity were successfully synthesized.
• Well-defined dendritic nanostructures were observed for PtNi, PtCo, and Pt(NiCo) alloys, but not for PtFe alloys due to precursor steric hindrance.
• Catalytic activity for the ORR increased with solute content, with Pt₃(NiCo)₂ showing superior performance.
• Pt₃(NiCo)₂ exhibited a 5-fold and 10-fold enhancement in area-specific and mass-specific activity, respectively, compared to Pt/C.

Conclusions:

• A facile one-pot synthesis enables the production of dendritic Pt-based nanoalloys.
• The composition significantly influences the ORR catalytic activity of these nanoalloys.
• The developed Pt-based nanoalloys represent highly efficient electrocatalysts for the ORR.