@inproceedings{d63c8b5e7a01462ca58131aba43535db,
title = "Oxygen reduction reaction activities for various-monolayer-thick Pt shells on PtxNi100-x(111)",
abstract = "We studied the oxygen reduction reaction (ORR) activities for two monolayer (ML)-thick Pt on PtxNi100-x(111) (Pt2ML/PtxNi100-x(111)) model core-shell catalysts fabricated by molecular beam epitaxy (MBE). Low-energy electron diffraction patterns for all Pt2ML/PtxNi100-x(111) showed six-fold surface symmetry with longrange ordering, indicating a (111) atomic arrangement of the topmost Pt shell layers. Furthermore, scanning tunneling microscopy images of the Pt2ML/Pt50Ni50(111) and Pt2ML/Pt25Ni75(111) surfaces exhibited Moir{\'e}-like height modulations, which are likely induced by large lattice mismatches between the topmost Pt(111) shell layers and the Pt-Ni(111) substrates. The ORR activity of Pt2ML/PtxNi100-x(111) increased with the Ni composition; the enhancement factors are 8-, 18-, and 25-fold vs. Pt(111) for Pt2ML/Pt75Ni25(111), Pt2ML/Pt50Ni50(111), and Pt2ML/Pt25Ni75(111), respectively. The results suggested that the Pt surface strains induced by lattice mismatches between the Pt shells and Pt-Ni substrates increased with the Ni composition, leading to a marked enhancement in ORR activity, particularly for Pt2ML/Pt25Ni75(111).",
author = "Masato Asano and Ryutaro Kawamura and Naoto Todoroki and Toshimasa Wadayama",
year = "2015",
month = jan,
day = "1",
doi = "10.1149/06917.0619ecst",
language = "English",
series = "ECS Transactions",
publisher = "Electrochemical Society Inc.",
number = "17",
pages = "619--624",
editor = "Gasteiger, {H. A.} and Ramani, {V. K.} and Fenton, {J. M.} and Schmidt, {T. J.} and Jones, {D. J.} and Ayers, {K. E.} and Perry, {K. A.} and Fuller, {T. F.} and Pivovar, {B. S.} and K. Shinohara and Buchi, {F. N.} and Mantz, {R. A.} and C. Coutanceau and P. Strasser and Weber, {A. Z.} and K. Swider-Lyons and H. Uchida and M. Edmundson and S. Mitsushima and Narayanan, {S. R.}",
booktitle = "Polymer Electrolyte Fuel Cells 15, PEFC 15",
edition = "17",
note = "Symposium on Polymer Electrolyte Fuel Cells 15, PEFC 2015 - 228th ECS Meeting ; Conference date: 11-10-2015 Through 15-10-2015",
}