title: Surface products and coverage dependence of dissociative ethane adsorption on Pt{110}-(1 x 2).
abstract: The dissociation of ethane on Pt{110}-(1 x 2) has been studied using supersonic molecular beam and temperature-programmed reaction techniques. The study unequivocally shows that the stable dissociation product of ethane on Pt{110}-(1 x 2) at all coverages is CCH2 at 350-400 K and CCH at 440 K. Temperature-programmed-reaction (TPR) experiments indicate that the CCH2 species decomposes to CCH with a reaction-limited peak temperature of 430 K. Above 450 K, the CCH species becomes unstable and decomposes with a peak temperature of 540 K. By 600 K, ethane dehydrogenates completely to form a surface carbon layer. The sticking probability is initially 0.02 at 370 K and 0.03 at 600 K and follows a linear (1-2theta) dependence for coverages of up to theta = 0.4 ML, where theta is defined as the number of C2Hx units per (1 x 2) unit cell. However, a much weaker coverage dependence at 800 K suggests that the carbon agglomerates into high-density islands.
authors.affiliation: Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW United Kingdom.
authors.forename: J J W
authors.initials: JJ
authors.lastname: Harris
authors.forename: V
authors.initials: V
authors.lastname: Fiorin
authors.forename: C T
authors.initials: CT
authors.lastname: Campbell
authors.forename: D A
authors.initials: DA
authors.lastname: King