Electrocatalysts for the Oxygen Reduction Reaction: From Bimetallic Platinum Alloys to Complex Solid Solutions

The oxygen reduction reaction has been the object of intensive research in an attempt to improve sluggish kinetics that limit performance renewable energy storage and utilization systems. Platinum or platinum bimetallic alloys are common choices as electrode material, but prohibitive costs hamper their use. Complex alloy materials, such high-entropy (HEAs), more generally, multiple principal component (MPCAs), have emerged a material capable overcoming limitations platinum-based materials. Theoretically, due large variety active sites, this new kind offers opportunity identify experimentally optimal binding site on catalyst surface. This review discusses recent advances application for existing experimental challenges benchmarking electrocatalytic properties these