Mixed-metal Pt monolayer electrocatalysts with improved CO tolerance

Area of Science:

• Materials Science
• Electrochemistry
• Computational Chemistry

Background:

• Proton-exchange membrane fuel cells (PEMFCs) are crucial for clean energy.
• CO poisoning of platinum (Pt) catalysts is a major challenge for PEMFC anode durability and efficiency.
• Minimizing Pt usage is essential for cost reduction.

Purpose of the Study:

• To design and evaluate novel Pt-M bimetallic monolayer catalysts supported on non-Pt metals.
• To improve catalyst stability against CO poisoning for PEMFC anodes.
• To reduce the overpotential for CO oxidation and lower overall material costs.

Main Methods:

• Periodic, self-consistent, density functional theory (DFT) calculations.
• CO-stripping voltammetry experiments.

Main Results:

• Designed Pt-M bimetallic monolayer catalysts supported on non-Pt metals.
• Demonstrated improved stability against CO poisoning compared to pure Pt.
• DFT predicted highly repulsive interactions between adsorbed CO molecules, leading to weaker binding and lower CO coverage.
• Facilitated oxidative removal of CO from catalytic surfaces.

Conclusions:

• The developed Pt-M catalysts offer enhanced stability and efficiency for PEMFC anodes.
• These catalysts reduce the need for expensive pure Pt, lowering manufacturing costs.
• The findings pave the way for more economical and durable fuel cell technologies.