Reversible formation of a PdCx phase in Pd nanoparticles upon CO and O-2 exposure
The structure and chemical composition of Pd nanoparticles exposed to pure CO and mixtures of CO and O-2 at elevated temperatures have been studied in situ by a combination of X-ray Diffraction and X-ray Photoelectron Spectroscopy in pressures ranging from ultra high vacuum to 10 mbar and from room temperature to a few hundred degrees celsius. Our investigation shows that under CO exposure, above