Platinum multicubes prepared by ni(2+) -mediated shape evolution exhibit high electrocatalytic activity for oxygen...

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Platinum ({Pt}) {100} facets are typically less active for the oxygen reduction reaction (ORR).
• Developing highly active and durable ORR catalysts is crucial for energy conversion technologies.

Purpose of the Study:

• To synthesize and characterize a novel platinum (Pt) branched structure, a multicube, with predominantly {100} facets.
• To investigate the ORR performance and durability of these Pt multicubes.
• To understand the structure-activity relationship governing the ORR on Pt multicubes.

Main Methods:

• Synthesis of Pt multicubes via Ni(2+)-mediated facet evolution from high-index {311} to {100} facets.
• Electrochemical characterization of ORR activity, including half-wave potential and current density.
• Assessment of catalyst durability.

Main Results:

• Pt multicubes, despite high {100} facet coverage, demonstrated remarkable ORR activity and durability.
• Performance approached that of state-of-the-art Pt-based ORR catalysts.
• Tunable ratios of high-index to low-index facets were achieved, correlating with performance.

Conclusions:

• The excellent ORR performance of Pt multicubes results from a synergistic effect of active sites on high-index facets and low resistance from flat {100} surfaces.
• This work presents a novel approach for facet-controlled synthesis of nanocatalysts.
• The findings offer new avenues for designing advanced ORR catalysts.