Highly Strained Interfaces and Phase Separation for Boosting Electrochemical Methanol Oxidation and Hydrogen...

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Optimizing noble metal nanomaterials for electrocatalysis requires precise control over multimetallic alloy heterostructures.
• Tailoring elemental distribution and lattice structures in these materials remains a significant challenge.

Purpose of the Study:

• To fabricate Cu-PtNi nanowires with specific interfaces and phase separation for enhanced electrocatalytic activity.
• To investigate the structure-performance relationship of these novel multimetallic nanomaterials.

Main Methods:

• Seeded synthesis of Cu-PtNi nanowires on a copper template.
• Electrochemical characterization, including methanol oxidation reaction (MOR) and hydrogen evolution reaction (HER) testing.
• Theoretical calculations and *operando* infrared reflection absorption spectroscopy (IRRAS).

Main Results:

• Cu-PtNi nanowires demonstrated superior MOR performance (7.73 A mg_Pt^-1) compared to binary alloys and commercial catalysts.
• A lattice-compressed Pt₃Ni (111)-Pt₃NiCu (100) interface was identified as a highly efficient active site.
• The nanowires also showed a reduced overpotential (35.2 mV at 10 mA cm^-2) for alkaline HER.

Conclusions:

• The fabricated Cu-PtNi nanowires offer an effective strategy for enhancing electrocatalytic performance.
• The unique interface promotes key intermediate adsorption/desorption for efficient MOR.
• This approach provides a pathway for designing advanced multimetallic nanomaterials for energy applications.