1.School of Materials Science and Engineering,University of Jinan,Jinan,China;2.State Key Laboratory of Silicon Materials, Key Laboratory of Advanced Materials and Applications for Batteries of Zhejiang Province and School of Materials Science and Engineering,Zhejiang University,Hangzhou, Hangzhou,China;3.Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials (Ministry of Education), School of Materials Science and Engineering,Shandong University,Jinan,China;4.School of Materials Science and Engineering,Tianjin University of Technology,Xiqing District, Tianjin,China
Abstract:
The oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) are crucial processes for energy conversion/storage systems, such as fuel cells, metal–air batteries, and water splitting. However, both reactions are severely restricted by their sluggish kinetics, thus requiring highly active, cost-effective, and durable electrocatalysts. Herein, we develop novel bifunctional nanocatalysts through surface nanoengineering of dealloying-driven nanoporous gold (NPG). Pd overlayers were precisely deposited onto the NPG ligament surface by epitaxial layer-by-layer growth. More importantly, the obtained NPG-Pd overlayer nanocatalysts exhibit remarkably enhanced electrocatalytic activities toward both the ORR and OER in alkaline media, benchmarked against a stateof- the-art Pt/C catalyst. The improved electrocatalytic performance is rationalized by the unique three-dimensional nanoarchitecture of NPG, enhanced Pd utilization efficiency from precise control of the Pd overlayers, and change in electronic structure, as revealed by density functional theory calculations.
