Spray-based and CVD Processes for Synthesis of Fuel Cell Catalysts and Thin Catalyst Layers

In spite of many efforts and improvements by thousands of scientists worldwide, PEMFCs and DMFCs have not been commercially used. State-of-the-art electrocatalysts for PEMFCs rely on large quantities of platinum to achieve acceptable performance levels. This presents a significant hurdle to market acceptance of FC-powered vehicles; a commercially viable electrocatalyst will require nearly an order-of-magnitude reduction in Pt usage to meet both cost and Pt availability constraints. Pt fine particles are dispersed on carbon blacks with a large surface area to reduce the total Pt used and to enhance catalytic activity. This activity depends not only on the primary structure of the catalyst Pt/carbon composites (i.e., carbon surface area, Pt particle size, Pt surface area, etc.), but also on the secondary structure (i.e., aggregation and agglomeration of carbon grains).