H-2/D-2 exchange reaction on mono-disperse Pt clusters: enhanced activity from minute O-2 concentrations
Journal article, 2016
The H-2/D-2 exchange reaction was studied on mono-disperse Pt-8 clusters in a mu-reactor. The chemical activity was studied at temperatures varying from room temperature to 180 degrees C using mass spectrometry. It was found that minute amounts of O-2 in the gas stream increased the chemical activity significantly. XPS and ISS before and after reaction suggest little or no sintering during reaction. A reaction pathway is suggested based on DFT. H-2 desorption is identified as the rate- limiting step and O-2 is confirmed as the source of the increased activity. The binding energy of platinum atoms in a SiO2 supported Pt-8 cluster is found to be comparable to the interatomic binding energies of bulk platinum, underlining the stability of the model system.
Author
J. N. Riedel
Technical University of Denmark (DTU)
M. D. Rotzer
Technical University of Munich
Mikkel Jørgensen
Competence Centre for Catalysis (KCK)
Chalmers, Physics, Chemical Physics
U. G. Vej-Hansen
Technical University of Denmark (DTU)
T. Pedersen
Technical University of Denmark (DTU)
B. Sebok
Technical University of Denmark (DTU)
F. F. Schweinberger
Technical University of Munich
P. C. K. Vesborg
Technical University of Denmark (DTU)
O. Hansen
Technical University of Denmark (DTU)
J. Schiotz
Technical University of Denmark (DTU)
U. Heiz
Technical University of Munich
I. Chorkendorff
Technical University of Denmark (DTU)
Catalysis Science and Technology
2044-4753 (ISSN) 2044-4761 (eISSN)
Vol. 6 18 6893-6900Subject Categories
Physical Sciences
DOI
10.1039/c6cy00756b