A High-Durability Graphitic Black Pearl Supported Pt Catalyst for a Proton Exchange Membrane Fuel Cell Stack

Area of Science:

• Electrochemistry
• Materials Science
• Catalysis

Background:

• Proton exchange membrane fuel cells (PEMFCs) are crucial for clean energy, but catalyst durability remains a challenge.
• Commercial platinum on carbon (Pt/C) catalysts degrade over time, limiting PEMFC lifespan.
• Developing robust catalysts is essential for advancing fuel cell technology.

Purpose of the Study:

• To synthesize and evaluate graphitized black pearl (GBP) supported platinum nanoparticle (Pt/GBP) catalysts for PEMFC applications.
• To compare the stability and durability of Pt/GBP catalysts against commercial Pt/C catalysts.
• To assess the performance of Pt/GBP in single-cell and stack-level durability tests.

Main Methods:

• Synthesis of Pt/GBP catalysts using a formic acid reduction method.
• Half-cell accelerated degradation tests (ADT) using two protocols.
• Single-cell ADT and a 1003-hour durability test on a PEMFC stack.
• Post-mortem morphology characterization of the catalyst.

Main Results:

• Pt/GBP catalysts exhibited excellent stability and durability compared to commercial Pt/C.
• Pt/GBP-membrane electrode assembly (MEA) showed enhanced reversal tolerance with a survival time of 205 minutes.
• A PEMFC stack with Pt/GBP demonstrated a slow voltage degradation rate (5.19% and 36 μV h⁻¹ at 1000 mA cm⁻²) after 1003 hours.
• Catalyst structure and particle size remained unchanged during dynamic load cycling, indicating superior stability.

Conclusions:

• Pt/GBP catalysts offer significant improvements in stability and durability for PEMFCs.
• The enhanced performance is attributed to the catalyst's structural integrity under operational stress.
• Pt/GBP presents a valuable and promising alternative to conventional Pt/C catalysts for next-generation PEMFCs.