Platinum-nickel catalyst: The effect of promoters in cis-oleic acid adsorption

SIMONETTI, S. , MARTIRENA, M. , ULACCO, S. , BRIZUELA, G

APPLIED SURFACE SCIENCE

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2013 vol. 264 p. 305 - 311

0169-4332

The study of the cis-oleic acid adsorption, on clean and promoted (K, Mg, Co, B or Pd) PtNi(1 1 1) surface was performed by quatum chemical calculations. The oleic acid adsorption on PtNi(1 1 1) surface shows a weak molecule-surface interaction. No preferential site for CC adsorption is computed and only the CO adsorption is favored on the clean PtNi(1 1 1) surface. The adsorption properties of the PtNi(1 1 1) are improved by promoters. The stability of the system is increased and the CC/surface distances are reduced when promoters are present. Among the considered promoters, Co has the best performance in terms of system stability. The lowest C p orbital substantially interacts with Pt and Co s, p and d orbitals. The change electron density of metal centers, enhance the CC adsorption being the Pt-C interaction the more favored. After adsorption, the strength of the CC, PtPt and PtCo bonds decrease while a molecule-surface bond is formed.