Mesoporous Pt@Pt-skin Pt₃Ni core-shell framework nanowire electrocatalyst for efficient oxygen reduction

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Designing platinum-based nanoarchitectures with controlled composition and morphology is crucial for improving electrocatalytic performance.
• Existing catalysts often face limitations in activity, stability, and efficient utilization of platinum.

Purpose of the Study:

• To rationally design and synthesize novel anisotropic mesoporous Pt@Pt-skin Pt3Ni core-shell framework nanowires.
• To evaluate the electrocatalytic activity and stability of these nanostructures for the oxygen reduction reaction.

Main Methods:

• Synthesis of Pt@Pt-skin Pt3Ni core-shell framework nanowires with controlled anisotropic and mesoporous structures.
• Electrocatalytic testing for the oxygen reduction reaction (ORR), including measurements of mass activity, specific activity, and long-term stability.
• Characterization of the catalyst's structure and surface properties.

Main Results:

• The synthesized catalyst exhibits a uniform core-shell structure with an ultrathin atomic-jagged Pt nanowire core and a mesoporous Pt-skin Pt3Ni framework shell.
• Exceptional mass activity (6.69 A/mgPt) and specific activity (8.42 mA/cm2 at 0.9 V vs RHE) for the oxygen reduction reaction.
• High stability demonstrated by negligible activity decay after 50,000 cycles.

Conclusions:

• The unique mesoporous Pt@Pt-skin Pt3Ni core-shell framework nanowire configuration enhances catalytic sites and weakens oxygenated species chemisorption.
• This design significantly boosts catalytic activity and stability for electrocatalysis, particularly the oxygen reduction reaction.
• The study highlights a promising strategy for developing highly efficient and stable platinum-based electrocatalysts with improved platinum utilization.