Reactive and inhibiting adsorbates for the catalytic electrooxidation of carbon monoxide on gold (210) as characterized by surface infrared spectroscopy

• Published in: Surface science Vol. 239; no. 3; pp. L543 - L547
• Main Authors: Chang, Si-Chung, Hamelin, Antoinette, Weaver, Michael J
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 01.12.1990; Amsterdam Elsevier Science; New York, NY
• Subjects: Adsorption; Chemistry; Electrochemistry; Exact sciences and technology; General and physical chemistry; Study of interfaces; Gold; Basic solution; Voltammetry; Crystal face; Transition metal; Experimental study; Acidic solution; Inorganic compound; Surface structure; Electrodes; Infrared spectrometry; Electrocatalysis; Oxidation; Carbon monoxide; Aqueous solution; Electrochemical reaction
• ISSN: 0039-6028; 1879-2758
• DOI: 10.1016/0039-6028(90)90216-U

Potential-dependent sequences of surface infrared spectra have been obtained during the voltammetric electrooxidation of solution carbon monoxide on ordered Au(210), in acidic, neutral, and alkaline aqueous media. Under optimal catalytic conditions, only a reactive form of adsorbed CO is detected, yielding a CO stretching frequency ( v CO) at ∼ 2100–2115 cm −1. The occurrence of reaction inhibition is accompanied by the displacement of this adsorbate by a lower v CO form, located at ∼1900–2000 cm −1, its appearance being favored by increasing surface exposure time and more negative dosing potentials. The mechanistic implications of such combined real-time infrared/voltammetric results are noted.