Electrochemical stability of pt-enriched topmost surface of Ni/Pt(111) prepared by molecular beam epitaxy

Naoto Todoroki, Y. Iijima, R. Takahashi, Y. Yamada, K. Matsumoto, T. Hayashi, Toshimasa Wadayama

Research output: Chapter in Book/Report/Conference proceedingConference contribution

1 Citation (Scopus)

Abstract

Oxygen reduction reaction (ORR) activity and stability of a molecular beam epitaxially (MBE) prepared Pt-enriched Ni 0.3nm /Pt(111) surface was investigated. Reflection high-energy electron diffraction (RHEED) patterns, and a scanning tunneling microscopic (STM) image indicated that the Pt-enriched surface has long-range-ordered six-fold symmetry with atomic-scale corrugations. ORR activity was estimated by kinetically-controlled current density at 0.9 V vs. a reversible hydrogen electrode, and the as-prepared Pt-enriched surface showed 8-times-higher ORR activity than clean Pt(111). The activity steeply reduced during potential cycling between 0.6 V and 1.0 V. After 1000 potential cycles, the enhancement factor was 2.5 and a cyclic voltammetry (CV) curve exhibited an increase in EC charge for the H addes region accompanied by the emergence of a 0.13 V redox feature caused by (110) surface defects. These results suggest that the electrochemical stability of the underlying Ni atoms determines the durability of Pt-Ni alloy catalysts.

Original languageEnglish
Title of host publicationPolymer Electrolyte Fuel Cells 12, PEFC 2012
Pages1707-1713
Number of pages7
Edition2
DOIs
Publication statusPublished - 2012 Dec 1
Event12th Polymer Electrolyte Fuel Cell Symposium, PEFC 2012 - 222nd ECS Meeting - Honolulu, HI, United States
Duration: 2012 Oct 72012 Oct 12

Publication series

NameECS Transactions
Number2
Volume50
ISSN (Print)1938-5862
ISSN (Electronic)1938-6737

Other

Other12th Polymer Electrolyte Fuel Cell Symposium, PEFC 2012 - 222nd ECS Meeting
CountryUnited States
CityHonolulu, HI
Period12/10/712/10/12

ASJC Scopus subject areas

  • Engineering(all)

Fingerprint Dive into the research topics of 'Electrochemical stability of pt-enriched topmost surface of Ni/Pt(111) prepared by molecular beam epitaxy'. Together they form a unique fingerprint.

Cite this