New Method to Synthesize Highly Active and Durable Chemically Ordered fct-PtCo Cathode Catalyst for PEMFCs

Area of Science:

• Electrochemistry
• Materials Science
• Catalysis

Background:

• Developing efficient and durable catalysts is crucial for advancing electrochemical energy conversion technologies.
• The oxygen reduction reaction (ORR) is a key process in fuel cells, but current catalysts suffer from limited performance and stability.

Purpose of the Study:

• To synthesize and characterize a novel platinum-cobalt (Pt-Co) catalyst with a chemically ordered face-centered tetragonal (fct) structure.
• To evaluate the catalytic activity and durability of the PtCo/CCCS catalyst for the oxygen reduction reaction (ORR).

Main Methods:

• Bottom-up synthesis involving Co-catalyzed pyrolysis of a chelate-complex and activated carbon black.
• Structural and compositional analysis to confirm the fct Pt-Co catalyst formation.
• Electrochemical testing, including power density measurements and durability tests (30,000 potential cycles).

Main Results:

• The fct-structured PtCo/CCCS catalyst achieved a 6% higher power density than commercial Pt/C at low Pt loading.
• Negligible performance loss was observed after 30,000 potential cycles, with less than 40% electrochemical surface area loss.
• The catalyst maintained uniform distribution and minimal particle size increase after accelerated stress tests, indicating exceptional durability.

Conclusions:

• The chemically ordered fct Pt-Co catalyst (PtCo/CCCS) exhibits superior activity and durability for the ORR.
• The unique structural and compositional properties contribute to the catalyst's enhanced stability and performance.
• This development offers a promising pathway for next-generation fuel cell catalysts.