Enhanced PEMFC durability with graphitized carbon black cathode catalyst supports under accelerated stress testing

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Durable carbon substrates are essential for commercializing fuel cell vehicles.
• Cathode catalyst support degradation impacts polymer electrolyte membrane fuel cell (PEMFC) performance and lifespan.
• Understanding anti-corrosion mechanisms is key to improving catalyst durability.

Purpose of the Study:

• To investigate the anti-corrosion properties of graphitized carbon black as a catalyst support in PEMFCs.
• To evaluate the durability of platinum (Pt) catalysts supported on graphitized carbon under accelerated stress conditions.
• To determine the effect of graphitization temperature on the performance and stability of the catalyst support.

Main Methods:

• Synthesis of graphitized carbon black supports treated at various temperatures.
• Preparation of platinum (Pt) catalysts using graphitized carbon supports.
• Accelerated stress testing of catalysts in PEMFCs, including simulated start-stop cycling and high potential holding.
• Analysis of catalyst durability through potential decay measurements and Pt particle size analysis.

Main Results:

• Graphitized carbon treated at 1800 °C exhibited superior antioxidation properties.
• The potential decay ratio at 1000 mA cm⁻² was reduced from 34.9% (commercial Pt/C) to 0.5% during high potential holding tests.
• Pt particle growth was significantly inhibited, decreasing from 0.95 nm (commercial Pt/C) to 0.08 nm, effectively alleviating particle coalescence.

Conclusions:

• Graphitized carbon black, particularly when treated at 1800 °C, serves as a highly durable support for Pt catalysts in PEMFCs.
• The enhanced graphitization improves resistance to oxidation and prevents Pt particle coarsening, leading to significantly improved fuel cell durability.
• These findings offer a promising strategy for enhancing the commercial viability of fuel cell vehicles through improved catalyst longevity.