Regensburg 2010 – wissenschaftliches Programm
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O: Fachverband Oberflächenphysik
O 35: Heterogeneous catalysis II
O 35.1: Vortrag
Dienstag, 23. März 2010, 15:00–15:15, H33
ReactorAFM; imaging supported catalysts at work — •M.E. Cañas-Ventura1, A. Ofitserov2, W. Onderwaater1, P.C. van der Tuijn1, G.J.C. van Baarle2, R.C.T. Koehler1, and J.W.M. Frenken1 — 1Kamerlingh Onnes Laboratory, Leiden Uni, Netherlands — 2Leiden Probe Microscopy BV, Netherlands
The atomic-scale investigation of supported catalysts is on the move towards experiments with state-of-the-art techniques close to industrial conditions: high pressures (P) and high temperatures (T). After successful experiments with a ReactorSTM[1], a miniature flow reactor integrated with a STM, we feel urged to widen range of model catalysts that can be studied under reaction conditions with atomic/near-atomic resolution, to the oxide-supported metal nanoparticle geometry. In this way we bridge not only the so-called "P gap" but also the "materials gap". For this purpose we have now developed the ReactorAFM. With special attention paid to vibration isolation, low-expansion materials and fast electronics, the instrument operates at T up to 570 K, P up to 5 bar and relatively high speeds. A new gas-flow system provides full control over the gas mixture and excellent time resolution and precise distribution of reaction products. The AFM is housed in a UHV system with several additional preparation and surface analysis techniques. The ReactorAFM also measures a tunneling current, which allows operation in a variety of modes with a wide range of simultaneously acquired signals. First scans and Δf vs. Z curves demonstrate the good behavior of the new setup.[1]B.L.M.Hendriksen et al.PRL 89,046101(2002)