In situ infrared spectroscopy of CO adsorbed at ordered Pt(100)-aqueous interfaces: Double-layer effects upon the adsorbate binding geometry

Journal Article · Thu Jun 14 04:00:00 EDT 1990 · Journal of Physical Chemistry; (USA)

DOI:https://doi.org/10.1021/j100375a062· OSTI ID:6330955

Chang, Sichung; Weaver, M J ^[1]

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1. Purdue Univ., West Lafayette, IN (USA)

Surface infrared spectra for carbon monoxide adsorbed on ordered Pt(100) in 0.1 M HClO{sub 4} are reported as a function of CO coverage, 0.1 {approx lt} {theta} {approx lt} 0.85, and electrode potential, {minus}0.25 V {le} E {approx lt} 0.25 V vs SCE. Vibrational C-O stretching bands, {nu}{sub co}, corresponding to both terminal and 2-fold bridging geometries are observed, with intensities that depend markedly upon E and {theta}. For coverages formed by dosing with dilute (ca. 2 {times} 10{sup {minus}5} M) CO solutions for varying times ({approx lt}15 min), alterations in {theta} at positive potentials (E {approx gt} 0.1 V) yield dramatic changes in the site occupancy in that bridging and terminal features are dominant for {theta} {approx lt} 0.3 and {theta} {approx gt} 0.7, respectively. Qualitatively similar, yet less marked, {theta}-induced alterations in the CO binding geometry are observed at negative potentials (E < 0 V vs SCE), where hydrogen rather than water constitutes the major coadsorbate.

• OSTI ID: 6330955
• Journal Information: Journal of Physical Chemistry; (USA), Journal Name: Journal of Physical Chemistry; (USA) Vol. 94:12; ISSN 0022-3654; ISSN JPCHA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical &amp; Physicochemical Properties
ADSORPTION
CARBON COMPOUNDS
CARBON MONOXIDE
CARBON OXIDES
CATALYSTS
CHALCOGENIDES
DATA
DATA ANALYSIS
ELEMENTS
EXPERIMENTAL DATA
INFORMATION
INFRARED SPECTRA
MEASURING INSTRUMENTS
MEASURING METHODS
METALS
NUMERICAL DATA
OXIDES
OXYGEN COMPOUNDS
PLATINUM
PLATINUM METALS
SORPTION
SPECTRA
SURFACE PROPERTIES
TRANSITION ELEMENTS