The effect of coadsorbed water on the stability, configuration and interconversion of formyl (HCO) and hydroxymethylidyne (COH) on platinum (111)

• DOI: 10.1016/j.cplett.2012.05.024
• Publication Date: 2012-05-23T12:46:45Z
• Authors: Líney Árnadóttir; Eric M. Stuve; Hannes Jónsson
• Keywords: Stoichiometry

Abstract Two forms of the methanol electro-oxidation intermediate with stoichiometry C:H:O, COH (hydroxymethylidyne) and HCO (formyl), on Pt (1 1 1) with and without coadsorbed water were studied using density functional theory calculations. The structure, adsorption energy and stability with respect to dissociation were calculated. Both HC O and C–OH were stable on clean Pt (1 1 1) and with a single coadsorbed water molecule, while only the HCO configuration was stable in the presence of a whole water layer. The vibrational modes of HC O on a bridge site showed no mode around 1700 cm −1 characteristic of C O stretch making it hard to distinguish it from C–OH.