Vibrational sum frequency generation studies of phase transition of CO on Pt(111) and Pt(111)/Ru electrodes

A. Lagutchev, G. Q. Lu, T. Takeshita, Dana D Dlott, Andrzej Wieckowski

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

Abstract

The potential-dependent (2×2)-3CO to a (√19×√19)R23.4°-13CO adlayer phase transition on Pt(111) with 0.1M H2SO4 electrolyte was studied using femtosecond broadband multiplex sum frequency generation (SFG) spectroscopy combined with linear scan voltammetry. Across the phase boundary the SFG atop intensity jumps, and at the same time the SFG spectrum of threefold CO sites is transformed into a bridge site spectrum with a small decrease in integrated SFG intensity. This occurs because the SFG signal is sensitive to both the coverage and changes in the local field that result from a changing adlayer structure. The phase transition is reversible with an Δ150 mV anodic overpotential and the forward (2×2)-3CO to a (√19×√19)R23.4°-13CO transition is slower than the reverse. Repeated cycles of phase transition indicate that the 25 μm electrolyte layer used here does not appreciably distort the potential-coverage relationships. The most recent data obtained on the electrode potential dependent SFG characteristics of the Pt(111)/Ru-CO system will be reported.

Original languageEnglish (US)
Title of host publication233rd ACS National Meeting, Abstracts of Scientific Papers
StatePublished - Dec 28 2007
Event233rd ACS National Meeting - Chicago, IL, United States
Duration: Mar 25 2007Mar 29 2007

Publication series

NameACS National Meeting Book of Abstracts
ISSN (Print)0065-7727

Other

Other233rd ACS National Meeting
CountryUnited States
CityChicago, IL
Period3/25/073/29/07

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ASJC Scopus subject areas

  • Chemistry(all)
  • Chemical Engineering(all)

Cite this

Lagutchev, A., Lu, G. Q., Takeshita, T., Dlott, D. D., & Wieckowski, A. (2007). Vibrational sum frequency generation studies of phase transition of CO on Pt(111) and Pt(111)/Ru electrodes. In 233rd ACS National Meeting, Abstracts of Scientific Papers (ACS National Meeting Book of Abstracts).