Pt-SnO_x Clusters With Weak Interfacial Interaction Boost Hydrogen Evolution

Area of Science:

• Materials Science
• Catalysis
• Electrochemistry

Background:

• Downsizing noble metal catalysts like platinum (Pt) is crucial for improving atomic efficiency in sustainable energy technologies.
• Understanding interfacial interactions in bimetallic nanostructures is key to optimizing catalytic performance.

Purpose of the Study:

• To develop a Pt-SnO_x nanocluster (NC) system with weak interfacial interaction for enhanced catalysis.
• To investigate the effect of SnO_x modulation on the catalytic properties of Pt and the hydrogen evolution reaction (HER) mechanism.

Main Methods:

• Synthesis of Pt-SnO_x nanoclusters (NCs) with controlled interfacial properties.
• Electrochemical characterization including overpotential and Tafel slope measurements.
• Theoretical calculations (e.g., DFT) to elucidate reaction mechanisms and interfacial effects.

Main Results:

• Pt-SnO_x NCs exhibited weak interfacial interaction with negligible charge transfer.
• Achieved an overpotential of 22 mV at 10 mA cm^-2 and a Tafel slope of 24 mV dec^-1, outperforming other Pt-based catalysts.
• Demonstrated efficient performance as a cathode in an ethanol-assisted proton exchange membrane electrolyzer, delivering 1.0 A cm^-2 at <1.5 V and stable operation for 70 hours.

Conclusions:

• The weak Pt/SnO_x interface effectively modulates the reaction pathway without compromising Pt's intrinsic activity.
• The Pt-SnO_x architecture facilitates hydrogen spillover, potentially shifting the HER mechanism to a more efficient Volmer-Tafel route.
• Pt-SnO_x NCs represent a promising catalyst for efficient and stable hydrogen production in electrochemical devices.