Elucidating the Doping Effect on the Electronic Structure of Thiolate-Protected Silver Superatoms by Photoelectron Spectroscopy.

Gas-phase photoelectron spectroscopy (PES) was conducted on [XAg (SPhMe ) ] (X=Ag, Au) and [YAg (SPhMe ) ] (Y=Pd, Pt), which have a formal superatomic core (X@Ag ) or (Y@Ag ) with icosahedral symmetry. PES results show that superatomic orbitals in the (Au@Ag ) core remain unshifted with respect to those in the (Ag@Ag ) core, whereas the orbitals in the (Y@Ag ) (Y = Pd, Pt) core shift up in energy by about 1.4 eV.

Partially oxidized iridium clusters within dendrimers: size-controlled synthesis and selective hydrogenation of 2-nitrobenzaldehyde.

Iridium clusters nominally composed of 15, 30 or 60 atoms were size-selectively synthesized within OH-terminated poly(amidoamine) dendrimers of generation 6. Spectroscopic characterization revealed that the Ir clusters were partially oxidized. All the Ir clusters efficiently converted 2-nitrobenzaldehyde to anthranil and 2-aminobenzaldehyde under atmospheric hydrogen at room temperature in toluene via selective hydrogenation of the NO2 group.

Finding the Most Catalytically Active Platinum Clusters With Low Atomicity.

On a subnanometer scale, an only one-atom difference in a metal cluster may cause significant transitions in the catalytic activity due to the electronic and geometric configurations. We now report the atomicity-specific catalytic activity of platinum clusters with significantly small atomicity, especially below 20. The atomic coordination structure is completely different from that of the larger face-centered cubic (fcc) nanocrystals.

Magic number Pt13 and misshapen Pt12 clusters: which one is the better catalyst?

A relationship between the size of metal particles and their catalytic activity has been established over a nanometer scale (2-10 nm). However, application on a subnanometer scale (0.5-2 nm) is difficult, a possible reason being that the activity no longer relies on the size but rather the geometric structure as a cluster (or superatomic) compound.