Insights into Spectator-Directed Catalysis: CO Adsorption on Amine-Capped Platinum Nanoparticles on Oxide Supports.

Introducing spectator molecules to the surface of supported noble metal nanoparticles is an innovative approach to improve the selectivity of heterogeneous catalysts. Colloidal synthesis of the nanoparticles allows researchers to select the spectator and the nanoparticle size, as well as the subsequent particle loading on different supports under well-defined conditions. However, understanding the interplay of the various effects that spectators can have on the catalytic properties of metal surfaces still requires further development.

Flexible NO -Functionalized N-Heterocyclic Carbene Monolayers on Au(111) Surface.

Invited for the cover of this issue are Elad Gross, F. Dean Toste, and co-workers at The Hebrew University and UC Berkeley. The image depicts the flexible anchoring geometry of addressable carbene molecules on Au surface, which upon exposure to reducing conditions changed their orientation from a standing into a flat-lying position.

Flexible NO -Functionalized N-Heterocyclic Carbene Monolayers on Au (111) Surface.

The formation of flexible self-assembled monolayers (SAMs) in which an external trigger modifies the geometry of surface-anchored molecules is essential for the development of functional materials with tunable properties. In this work, it is demonstrated that NO -functionalized N-heterocyclic carbene molecules (NHCs), which were anchored on Au (111) surface, change their orientation from tilted into flat-lying position following trigger-induced reduction of their nitro groups. DFT calculations identified that the energetic driving force for reorientation was the lower steric hindrance and stronger interactions between the chemically reduced NHCs and the Au surface.

Methanol oxidation on the Pt(321) surface: a theoretical approach on the role of surface morphology and surface coverage effects.

We investigated methanol oxidation, decomposition and carbonylation reactions on a high indexed Pt(321) surface. Adsorption studies of the reactants and reaction products were analyzed, where the favourable binding was found on the low coordinated atoms which are located on the step edges of this surface. The dependence of the reaction mechanism on the surface structure could be observed by analysis of methanol decomposition via O-H and C-H bond cleavage, where the latter showed a significant preference in energy.

Elucidating the Influence of Anchoring Geometry on the Reactivity of NO-Functionalized N-Heterocyclic Carbene Monolayers.

The development of chemically addressable N-heterocyclic carbene (NHC) based self-assembled monolayers (SAMs) requires in-depth understanding of the influence of NHC's anchoring geometry on its chemical functionality. Herein, it is demonstrated that the chemical reactivity of surface-anchored NO-functionalized NHCs (NO-NHCs) can be tuned by modifying the distance between the functional group and the reactive surface, which is governed by the deposition technique. Liquid deposition of NO-NHCs on Pt(111) induced a SAM in which the NO-aryl groups were flat-lying on the surface.