Probing the surface of platinum nanoparticles with 13CO by solid-state NMR and IR spectroscopies.
The synthesis and full characterization of platinum nanoparticles (Pt NPs) prepared by decomposition of the Pt(dba)2 complex in the presence of CO and H2 and stabilized either sterically by a polymer, polyvinylpyrrolidone or chemically by a ligand, diphenylphosphinobutane, are reported. In these studies, (13)CO was used as a probe molecule to investigate the surface of the particles, using IR and solid-state NMR spectroscopies with magic angle spinning (MAS-NMR). Three nanosystems with different sizes are described: Pt/PVP/(13)CO (monomodal: 1.2 nm), Pt/dppb/(13)CO (bimodal: 1.2 nm and 2.0 nm) and Pt/dppb/H2 (monomodal: 2.0 nm) NPs. Spectroscopic data suggest a modification of the electronic state of the nanoparticles between 1.2 nm and 2.0 nm which can be related to the presence of Knight shift.
CNRS, LCC (Laboratoire de Chimie de Coordination du CNRS), BP 44099, 205 Route de Narbonne, F-31077 Toulouse Cedex 4, France. Karine.Philippot@lcc-toulouse.fr.
Solen
S
Kinayyigit
Patricia
P
Lara
Pierre
P
Lecante
Karine
K
Philippot
Bruno
B
Chaudret