Platinum Group Metal Clusters: From Gas‐Phase Structures and Reactivities towards Model Catalysts

Abstract

Transition-metal clusters have long been proposed as model systems to study heterogeneous catalysts. In this Concept article we show how advanced spectroscopic techniques can be used to determine the structures of gas-phase transition-metal clusters and their complexes with small molecules. Combined with computational studies, this can help to develop an understanding of the reactivity of these catalytic models.

Theoretical DFT study of homonuclear and binary transition-metal dimers

“…Exploring physicochemical properties of nanoparticles with the aim of gaining a deeper insight on the basic mechanisms that drive their unique behavior has only been possible by developing novel methodologies for tailoring nanomaterials with the potential to fulfill the requirements of the chemical, medical, or petroleum industries, once the inherent synthesis drawbacks have been overcome. Modern theoretical developments have provided the tools to investigate nanoscale materials and nowadays the outcome of computational models may lead to perform experiments to obtain nanomaterials by design, for example in catalysis and other important technological areas [3,4]. Transition and noble metal atomic clusters are currently applied in a variety of fundamental catalytic processes [5,6], hence the importance of tuning theoretical tools able to predict their physical and chemical properties with a high degree of reliability.…”

Doping Effects in Cluster‐Mediated Bond Activation

“…In this Minireview,Iwill focus on two types of reactions by "doped" cluster ions,t hat is,1 )oxidation of CO under ambient conditions,a nd 2) the competition between hydrogen-atom transfer to the cluster or oxygen-atom delivery to hydrocarbons.W hile Iw ill address questions related to,f or example,the role of charge and spin states,the nature of the active site in the cluster,ordiscuss mechanistic features,Iwill refrain from describing any experimental or computational details,asthese can be found in the original articles.Also,gas-phase spectroscopic studies of cluster ions conducted in the context of selective bond activation [26,[32][33][34][35] will not be discussed in detail;rather, one system may suffice to illustrate the power of these techniques when combined with computational work.…”

Chemical Reactivity on Gas‐Phase Metal Clusters Driven by Blackbody Infrared Radiation

“…[1] Here, we report a study of entrance-channel complexes for one such important catalytic process, the decomposition of nitrous oxide on small gas-phase rhodium clusters. In ion-storage experiments under nominally collision-free (ultrahighvacuum, UHV) conditions, absorption of nascent blackbody infrared radiation has been used to initiate both chemical reactivity and fragmentation of gas-phase rhodium clusters with molecularly adsorbed nitrous oxide molecules.…”