Durable Tungsten Carbide Support for Pt-Based Fuel Cells Cathodes
Oran Lori, Shmuel Gonen, Omree Kapon, Lior Elbaz
Abstract
In an effort to develop durable, corrosion-resistant catalyst support materials for polymer electrolyte fuel cells, modified polymer-assisted deposition method was used to synthesize tungsten carbide (WC, WC1–x), which was later used as a support material for Pt-based oxygen reduction reaction catalyst, as an alternative for the corrosion-susceptible, carbon supports. The Pt-deposited tungsten carbide’s corrosion-resistance, oxygen reduction reaction electrocatalysis, and durability were studied and compared to that of Pt/C. Bulk free carbon was found to be absent from the ceramic matrix which had particle size in the range of 2–25 nm. Tungsten carbide support appears to enhance the oxygen reduction activity on Pt, showing an increase in mass activity (nearly 2-fold at 0.85 V vs RHE) and specific activity (more than 7 times higher), alongside decrease in overpotential, in comparison to Pt/C. A significant increase in durability was also observed with the tungsten carbide-based system.