title: Potential Energy Surface Profile of the Oxygen Reduction Reaction on a Pt Cluster:  Adsorption and Decomposition of OOH and H2O2.
abstract: Because of their essential roles on determining pathways of the oxygen reduction reaction (ORR), the adsorption behavior and decomposition of the radical OOH and hydrogen peroxide on Pt clusters (Ptn, n = 3, 6, and 10) are extensively investigated using density functional theory. Two types of adsorption of the radical OOH on Pt clusters are found. One-end adsorbed hydrogen peroxide H2O2, arising from reduction of adsorbed OOH, is also located on Pt3, with an adsorption energy of -0.63 eV, suggesting that the ORR may proceed via a series pathway generating H2O2 as an intermediate. However, since OOH readily decomposes on Pt3 into atop adsorbed atomic oxygen and hydroxyl with an activation energy of only ∼0.25 eV, the OOR may take place preferentially via a direct pathway without H2O2 produced. A potential energy surface profile for the ORR is proposed, and the adsorption properties of other involved oxide species are characterized.
authors.affiliation: Department of Chemical Engineering, Texas A&M University, 3122 TAMU, College Station, Texas 77843.
authors.forename: Yixuan
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Chemical Engineering, Texas A&M University, 3122 TAMU, College Station, Texas 77843.
authors.forename: Perla B
authors.initials: PB
authors.lastname: Balbuena