Development of Highly Active and Durable Platinum Core-shell Catalysts for Polymer Electrolyte Fuel Cells

Polymer electrolyte fuel cells (PEFCs) are clean and highly efficient energy sources without emission of global warming CO2 gas, and have been developed as electric power sources in fuel cell vehicles (FCVs). One of the most important issues in the development of PEFCs is currently a drastic reduction of Pt usage by an improvement in the activity for oxygen reduction reaction at the Pt cathode catalyst. To improve the activity of the Pt catalyst, we have so far developed core-shell catalysts using Pt monolayer shell covered on Au or Pd core materials. In this review article, a novel preparation method for Pt monolayer formation on non-Pt core nanoparticles that is suitable for mass production of the core-shell catalysts, and the results on the activity and durability of the resulting core-shell catalysts are overviewed. The potentials and difficulties of the core-shell catalysts for use in practical FCVs are discussed.