Nanoscale Engineering of Efficient Oxygen Reduction Electrocatalysts by Tailoring the Local Chemical Environment of Pt Surface Sites
By Cleve, Tim Van; Moniri, Saman; Belok, Gabrielle; More, Karren L.; Linic, Suljo
Published in ACS Catalysis
2017
Abstract
The oxygen reduction reaction is the limiting half-reaction in hydrogen fuel cells. While Pt is the most active single component electrocatalyst for the reaction, it is hampered by high cost and low reaction rates. Most research to overcome these limitations has focused on Pt/3d alloys, which offer higher rates and lower cost. Herein, we have synthesized, characterized, and tested alloy materials belonging to a multilayer family of electrocatalysts. The multilayer alloy materials contain an AuCu alloy core of precise composition, surrounded by Au layers and covered by a catalytically active Pt surface layer. Their performance relative to that of the commercial Pt standards reaches up to 4 times improved area-specific activity. Characterization studies support the hypothesis that the activity improvement originates from a combination of Au