INTEC   05402
INSTITUTO DE DESARROLLO TECNOLOGICO PARA LA INDUSTRIA QUIMICA
Unidad Ejecutora - UE
artículos
Título:
Molecular Adsorption Changes the Quantum Structure of Oxide-Supported Gold Nanoparticles: Chemisorption versus Physisorption
Autor/es:
STIEHLER, CHRISTIAN; CALAZA, FLORENCIA; SCHNEIDER, WOLF-DIETER; NILIUS, NIKLAS; FREUND, HANS-JOACHIM
Revista:
PHYSICAL REVIEW LETTERS
Editorial:
AMER PHYSICAL SOC
Referencias:
Lugar: New York; Año: 2015 vol. 115 p. 368041 - 368045
ISSN:
0031-9007
Resumen:
STM conductance spectroscopy and mapping has been used to analyze the impact of molecularadsorption on the quantized electronic structure of individual metal nanoparticles. For this purpose,isophorone and CO2, as prototype molecules for physisorptive and chemisorptive binding, were dosed ontomonolayer Au islands grown on MgO thin films. The molecules attach exclusively to the metal-oxideboundary, while the interior of the islands remains pristine. The Au quantum well states are perturbed dueto the adsorption process and increase their mutual energy spacing in the CO2 case but move together inisophorone-covered islands. The shifts disclose the nature of the molecule-Au interaction, which relies onelectron exchange for the CO2 ligands but on dispersive forces for the organic species. Our experimentsreveal how molecular adsorption affects individual quantum systems, a topic of utmost relevance forheterogeneous catalysis.