| Autor: |
Brieger, Claudia, Melke, Julia, Kaghazchi, Payam, Roth, Christina |
| Zdroj: |
ECS Transactions; September 2015, Vol. 69 Issue: 17 |
| Abstrakt: |
Temperature dependent adsorption of CO has been studied on Pt/SiO2nanoparticles with Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS) under different CO concentrations and flow conditions. In all experiments almost only linearly adsorbed CO could be detected. The spectra have been fitted with three bands and were assigned with DFT calculations which specifically include the nanoparticle structure of the platinum clusters. The relative intensity of these bands strongly depends on the temperature and on the CO flow conditions. When CO is not replenished, desorption starts even at room temperature with only the two bands at lower wavenumber remaining at higher temperatures.It could be shown that for catalysts containing a size distribution of nanoparticles, not only the various adsorption sites (i.e. facets, edges and corners), but also the different cluster sizes need to be considered for the precise description of CO adsorption. |
| Databáze: |
Supplemental Index |
| Externí odkaz: |
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