Description
SMSI is a phenomenon observed in supported metal catalyst system, in which reducible metal-oxide supports can form overlayers over the active metal nanoparticles (NPs) surface, under hydrogen (H2) environment at elevated temperatures [1]. To study the SMSI on ensembles of NPs and in-situ, element-sensitive technique is needed, able to measure nanoscale changes in atomic distribution of metal atoms. X-ray standing wave (XSW) technique is suited for this, as it allows measure changes in atomic distribution profile at sub-nanometer scale by measuring angular-dependent X-ray fluorescence (XRF).Here, we study a model catalyst system of Co NPs (~10-15 nm) supported on TiO2 (~2.5 nm). The model catalyst system was synthesized on top of a multilayer mirror (MLM) of MoN/Si3N4. By generating XSW using MLM, maximum sensitivity for the changes in Ti atomic distribution profile can be achieved. Two samples: MLM without Co NPs and MLM with Co NPs were studied. The synthesis of Co NPs was done via spark ablation. The samples were reduced under H2 environment at 450℃ and 600℃ for 1 hour and characterized by a combination of X-ray reflectivity and XRF (under XSW conditions). This novel methodological approach as well as first results hinting towards SMSI in the model catalyst system will be presented.
| Period | 3 Apr 2023 → 5 Apr 2023 |
|---|---|
| Event title | NWO Physics@Veldhoven 2023 |
| Event type | Conference |
| Location | Veldhoven, NetherlandsShow on map |
| Degree of Recognition | National |