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
Danmarks Tekniske Universitet
M. D. Rotzer
Technische Universitat Munchen
Mikkel Jørgensen
Competence Centre for Catalysis (KCK)
Chalmers, Physics, Chemical Physics
U. G. Vej-Hansen
Danmarks Tekniske Universitet
T. Pedersen
Danmarks Tekniske Universitet
B. Sebok
Danmarks Tekniske Universitet
F. F. Schweinberger
Technische Universitat Munchen
P. C. K. Vesborg
Danmarks Tekniske Universitet
O. Hansen
Danmarks Tekniske Universitet
J. Schiotz
Danmarks Tekniske Universitet
U. Heiz
Technische Universitat Munchen
I. Chorkendorff
Danmarks Tekniske Universitet
Catalysis Science and Technology
2044-4753 (ISSN) 2044-4761 (eISSN)
Vol. 6 18 6893-6900Subject Categories (SSIF 2011)
Physical Sciences
DOI
10.1039/c6cy00756b