CO dissociation and CO2 formation catalysed by Na atoms adsorbed on Ni(111)

CO chemisorption at vacancies of supported graphene films: a candidate for a sensor?

“…These observations indicate that the G sheet attaches again to the Ni substrate, although the initial state is not fully recovered: a shoulder at E b = 283.4 eV is indeed present in the C 1s region and small losses at 90 and 62 meV are also visible. The C 1s component at 283.4 eV corresponds to nickel carbide 27 while the vibration at 62 meV is compatible with its vertical stretch (reported at 50 meV for C/Ni(100) 30 and at 59 meV for C/Ni(111) in presence of Na 20 ).…”

“…Starting from the G/Ni(111) ( Fig. 1A), we can see that before ion bombardment weak losses at 63 meV and 90 meV are present corresponding to defects of graphene 20 z-polarized phonon, 21 respectively. No vibrational signature of CO adsorption has been observed on the pristine layer exposed at RT under UHV conditions, 16 while additional peaks show up at 52 meV, 237 meV and 253 meV for the ion bombarded graphene layer (indicated as G*).…”

“…Starting from the G/Ni(111) (Fig. 1A), we can see that before ion bombardment weak losses at 63 meV and 90 meV are present corresponding to defects of graphene 20 and to the a Dipartimento di Fisica, Universita `di Genova, 16146 Genova, Italy. E-mail: celasco@fisica.unige.it b IMEM-CNR Unita `Operativa di Genova, 16146 Genova, Italy † Electronic supplementary information (ESI) available: Details of the experimental methods; assignment of the vibrational losses not related to CO in the spectra of Fig.…”

Bridging the structure gap: Chemistry of nanostructured surfaces at well-defined defects

“…For reactive systems dissociation in presence of a promoter is active already at low T . It is indeed observed at 320 K on the LMI Pd (110) surface with high K pre-coverage [359] and at 160 K on Ni (111) in presence of Na atoms [360]. The simultaneous effect of steps and of alkali atom promoters enables a further reduction of the CO dissociation temperature and of the critical coverage of the promoter itself.…”