title: Enhanced Oxygen Reduction Activity of Platinum Monolayer on Gold Nanoparticles.
abstract: The increase in oxygen binding energy was previously proposed to account for the lower oxygen reduction activity of a Pt monolayer supported on Au(111) single crystal than that on Pd(111) and pure Pt(111) surfaces. This single-crystal based understanding, however, cannot explain the new finding of a 1.6-fold increase of oxygen reduction activity on Pt monolayer-modified 3-nm Au nanoparticles (Pt/Au/C) in comparison with that on Pt/Pd/C with a similar particle size. The Pt/Au/C catalyst also has an activity higher than that of a state-of-the-art 2.8-nm Pt/C catalyst. Our new experimental results and density functional theory calculations demonstrate that a significant compressive strain in the surface of the core nanoparticles plays a role in the observed activity enhancement.
authors: †UTC Power, South Windsor, Connecticut 06074, United States.
authors: Minhua
authors: M
authors: Shao
authors: ‡United Technologies Research Center, East Hartford, Connecticut 06118, United States.
authors: Amra
authors: A
authors: Peles
authors: †UTC Power, South Windsor, Connecticut 06074, United States.
authors: Krista
authors: K
authors: Shoemaker
authors: ‡United Technologies Research Center, East Hartford, Connecticut 06118, United States.
authors: Mallika
authors: M
authors: Gummalla
authors: §Chemistry Department, State University of New York at Binghamton, Binghamton, New York 13902, United States.
authors: Peter N
authors: PN
authors: Njoki
authors: §Chemistry Department, State University of New York at Binghamton, Binghamton, New York 13902, United States.
authors: Jin
authors: J
authors: Luo
authors: §Chemistry Department, State University of New York at Binghamton, Binghamton, New York 13902, United States.
authors: Chuan-Jian
authors: CJ
authors: Zhong
keywords: density functional theory; electrocatalyst; gold nanoparticle; oxygen reduction reaction; particle size effect; platinum monolayer; shape control