High-performance ionomer-free gas diffusion cathodes with low Pt loading for proton exchange membrane water...

Area of Science:

• Materials Science
• Electrochemistry
• Chemical Engineering

Background:

• Platinum is a key catalyst for hydrogen evolution reaction (HER) in acidic media.
• Its activity in proton exchange membrane water electrolysis (PEMWE) is often limited by poor cathode catalyst utilization.
• Optimizing platinum nanoparticle synthesis and distribution is crucial for improving PEMWE efficiency.

Purpose of the Study:

• To synthesize and characterize platinum nanoparticles with atomic precision on a microporous-layer-coated gas diffusion layer for PEMWE.
• To evaluate the catalytic performance and stability of the developed electrode with low platinum loading.
• To demonstrate enhanced mass activity and durability compared to benchmark platinum catalysts.

Main Methods:

• Atomic layer deposition (ALD) was employed for precise synthesis of platinum nanoparticles.
• Characterization of the gas diffusion electrode with controlled platinum loading and particle size.
• Performance testing in proton exchange membrane water electrolysis under various operating conditions.

Main Results:

• The developed electrode achieved exceptionally low platinum loading (1.08-5.40 μg cm⁻²).
• Demonstrated mass activity at least one order of magnitude higher than benchmark platinum catalysts.
• Exhibited exceptional stability over 200 hours at 1 A cm⁻² and robust performance under dynamic voltage cycling.

Conclusions:

• Atomic precision synthesis of platinum nanoparticles significantly enhances catalyst utilization and activity in PEMWE.
• The developed electrode offers a promising pathway for cost-effective and high-performance water electrolysis.
• This approach addresses the underestimation of platinum's catalytic potential in PEMWE by optimizing its application.