H2/D2 exchange reaction on mono-disperse Pt clusters: enhanced activity from minute O2 concentrations†
Abstract
The H2/D2 exchange reaction was studied on mono-disperse Pt8 clusters in a μ-reactor. The chemical activity was studied at temperatures varying from room temperature to 180 °C using mass spectrometry. It was found that minute amounts of O2 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. H2 desorption is identified as the rate-limiting step and O2 is confirmed as the source of the increased activity. The binding energy of platinum atoms in a SiO2 supported Pt8 cluster is found to be comparable to the interatomic binding energies of bulk platinum, underlining the stability of the model system.
- This article is part of the themed collection: Nanocatalysis