Prospects of Platinum-Based Nanostructures for the Electrocatalytic Reduction of Oxygen

Abstract

Platinum-based electrocatalysts for fuel cells have been the subject of a vast collection of research over the past several decades. While the intrinsic area-specific activity of these materials has arguably been optimized, the mass-specific activity and long-term durability still have room for improvement, and achieving a co-optimization of activity and stability requires consideration of a number of trade-offs. In this Viewpoint, we provide an assessment of prospects for the continued development of ORR electrocatalysts, focusing on recent advances and guidelines for maximizing the efficient use of platinum. Our discussion starts with a brief review of Pt-based alloy electrocatalysts, illustrating what we perceive as a necessary progression toward core/shell nanostructures—particularly those composed of a nonprecious core and a Pt shell. Shell thickness is discussed in terms of trade-offs between stabilization of the nonprecious metal core and permission of strain and/or ligand effects on the surface—in...