The adsorption and oxidation of carbon monoxide at the Pt(111)/electrolyte interface: atomic structure and surface relaxation
نویسنده
چکیده
Using in-situ X-ray diffraction we have studied the adsorption of CO onto Pt(111) in pure perchloric acid. The adsorption of CO at an applied electrode potential of 0.05 V (versus the reversible hydrogen electrode) causes expansion of the topmost Pt atomic layer by ~4% of the bulk lattice spacing. At this potential the adsorbed CO forms a compressed p(2×2) adlayer which fully covers the Pt surface. As the potential is stepped positively, the p(2×2) structure undergoes an order–disorder transition which appears to be triggered by oxidation of a small fraction of the adsorbed CO adlayer and is reversible or irreversible according to the overpressure of CO. © 1999 Elsevier Science B.V. All rights reserved.
منابع مشابه
Infrared reflection absorption study of carbon monoxide adsorption on Fe-deposited Pt(111) surface
Infrared reflection absorption spectroscopy (IRRAS) was used to investigate carbon monoxide (CO) adsorption on sub-monolayer (ML)-thick Fe deposited Pt(111). The CO exposure to a clean Pt(111) surface at room temperature yielded linear-bonded and bridgebonded CO-Pt bands at 2090 and 1850 cm. The CO-Pt band intensities decreased steeply with increasing Fe thickness. For a 1-ML-thick-Fe/Pt surfac...
متن کاملMechanism of CO oxidation on Pt(111) in alkaline media.
Electrochemical techniques, coupled with in situ scanning tunneling microscopy, have been used to examine the mechanism of CO oxidation and the role of surface structure in promoting CO oxidation on well-ordered and disordered Pt(111) in aqueous NaOH solutions. Oxidation of CO occurs in two distinct potential regions: the prepeak (0.25-0.70 V) and the main peak (0.70 V and higher). The mechanis...
متن کاملEthanol electrooxidation on the Co@Pt core-shell nanoparticles modified carbon-ceramic electrode in acidic and alkaline media
In this study, the electrocatalytic activity of the Co@Pt core-shell nanoparticles toward the ethanol oxidation reaction has been investigated by cyclic voltammetry and chronoamperometry in acidic and alkaline media in details. The physicochemical data obtained in alkaline solution are compared to those in acidic solution. The obtained results demonstrate that while in the both media Co@Pt core...
متن کاملCatalytic Oxidation of Carbon Monoxide by Cobalt Oxide Catalysts Supported on Oxidized-MWCNT
Cobalt oxide catalysts supported on oxidized multi-walled carbon nanotubes (MWCNT) for the low-temperature catalytic oxidation of carbon monoxide were prepared by an impregnation-ultrasound method. These catalysts were characterized by N2 adsorption/desorption, TEM, XRD, Raman, and H2-TPR methods. The XRD and Raman results indicated that the phase of the synthesized cobalt...
متن کاملKinetic study of CO desorption from cathodic electrochemically treated carbon paper supported Pt electrodes
Platinum particles were grown directly by an electrodeposition process on electrochemically treated carbon paper (CP) for kinetic study of carbon monoxide (CO) desorption. The treatment on CP was performed by applying −2 V for cathodic oxidation over 5 min. Treated CP was characterized by FTIR to investigate the oxygen groups on its surface. CO surface coverage at each temperature was determine...
متن کامل