Determination of adsorption sites of pure and coadsorbed CO on Ni(111) by high resolution X-ray photoelectron spectroscopy

Understanding CO-stripping mechanism from NiUPD/Pt(110) in view of the measured nickel formal partial charge number upon underpotential deposition on platinum surfaces in sulphate media

“…As stated above, the presence of peak 1 for (CO ad + Ni UPD )-stripping experiment, the coulometry of which is close to that for CO ad -stripping voltammograms in the absence of nickel in solution, is a strong evidence that after peak 2, the CO-adlayer has been rebuilt over the Pt(1 1 0)-(1 × 2) surface freed from any Ni UPD atoms. The fast CO ad diffusion coefficient on nickel substrates, as monitored in UHV conditions for nickel crystals [43][44][45][46][47] or for Ni/W(1 1 0) surfaces [48], is consistent with such scenario. In addition, CO ad displays a greater stability over platinum surface, at least for singles crystals in the (1 1 1) orientation in UHV conditions [48].…”

Nickel-underpotential deposition on Pt(110) in sulphate-containing media

“…8(c)) is related to CO and Ni-UPD stripping, which shows that CO adsorbed on Ni-UPD is less stable than on Pt(1 1 0). Nickel submonolayer on Pt(1 1 0) exhibits remarkable properties for CO-oxidation, maybe due to the CO higher mobility over nickel than over platinum, as already observed under UHV-conditions [24][25][26][27][28]. Such an interesting behaviour of nickel submonolayer as already been reported by Pavao et al for Ni/W(1 1 0) [29].…”

Photoemission study of methanol decomposition on Pt/Ni(111) surface alloy

“…On clean nickel, peak at 285.2 eV was resolved, its position matches to adsorption of CO in bridge positions [18] and also the O1s peak at 531.1 eV is in agreement with published values in Ref. [18]. A small peak at 284.5 eV was in context with further evolution on both samples ascribed to CHO.…”