Iron-based cathode catalyst with enhanced power density in polymer electrolyte membrane fuel cells

Area of Science:

• Electrochemistry
• Materials Science
• Catalysis

Background:

• Polymer-electrolyte-membrane fuel cells (PEMFCs) are key for vehicle propulsion.
• Platinum (Pt) catalysts are expensive, driving research for cheaper alternatives.
• Iron-based (Fe) catalysts show promise but suffer from low power density due to poor mass transport.

Purpose of the Study:

• To develop a novel, low-cost Fe-based electrocatalyst for PEMFCs.
• To enhance mass-transport properties and volumetric activity in Fe-based catalysts.
• To achieve power density comparable to commercial Pt-based cathodes.

Main Methods:

• Synthesized a novel electrocatalyst using iron-acetate, phenanthroline, and a zeolitic-imidazolate-framework (ZIF).
• Utilized the ZIF as a host for catalyst precursors, followed by heat treatment.
• Fabricated a cathode using the derived electrocatalyst and tested its performance in H(2)-O(2) fuel cells.

Main Results:

• The developed Fe-based catalyst demonstrated increased volumetric activity and improved mass-transport properties.
• The best performing cathode achieved a power density of 0.75 W cm(-2) at 0.6 V.
• Performance was comparable to a commercial Pt-based cathode under identical testing conditions.

Conclusions:

• The novel iron-acetate/phenanthroline/ZIF-derived electrocatalyst offers a viable, cost-effective alternative to Pt for PEMFCs.
• Enhanced mass transport and volumetric activity are crucial for improving Fe-based catalyst performance.
• This advancement holds significant potential for reducing fuel cell costs and promoting wider adoption in vehicle applications.