title: Physisorption and chemisorption on silver clusters.
abstract: Adsorption and coadsorption studies on free silver clusters show that nitrogen physisorbs like rare gases, whereas oxygen chemisorbs with similarities and differences to bulk silver surfaces. Silver nanoparticles activate, or even dissociate adsorbed oxygen molecules. The global electron configurations of the adsorbent and adsorbate dominate the stability at small clusters. This is more important than geometry and site effects. Due to electronic shell effects and electron pairing, the activation of oxygen strongly varies with size. At more than 40 free electrons in the complex, such quantum effects start to blur. The size dependence becomes smoother and general trends govern the reactivity, which is driven by the interaction between the charge state of the nanoparticle and the charge transfer of the reaction.
authors: Laboratoire Aimé Cotton, CNRS, Université Paris-Sud, 91405 Orsay Cedex (France). Martin.Schmidt@u-psud.fr.
authors: Martin
authors: M
authors: Schmidt
authors: Albert
authors: A
authors: Masson
authors: Hai-Ping
authors: HP
authors: Cheng
authors: Catherine
authors: C
authors: Bréchignac
mesh_terms: D000327:Adsorption; D053768:Metal Nanoparticles / Q000737:chemistry*; D010100:Oxygen / Q000737:chemistry*; D010316:Particle Size; D012834:Silver / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D012834:Silver; D010100:Oxygen
keywords: chemisorption; clusters; nitrogen; oxygen; silver