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MI: Fachverband Mikrosonden

MI 6: Scanning Probe Microscopy

MI 6.1: Vortrag

Dienstag, 17. März 2015, 11:30–11:45, EMH 225

The ReactorAFM: a high-pressure high-temperature NC-AFM for catalysis — Sander B. Roobol, •Matthijs A. van Spronsen, Mirthe Bergman, Peter C. van der Tuijn, Raymond C.T. Koehler, Joost W.M. Frenken, and Irene M.N. Groot — Huygens-Kamerlingh Onnes Laboratory, Leiden University, The Netherlands

To gain fundamental understanding of the mechanisms in catalytic reactions, it is essential to study gas-surface interactions by in-situ microscopy. The ReactorAFM is a novel instrument enabling atomic-scale imaging of oxide-supported metallic nanoparticles under high-pressure, high-temperature conditions. The ReactorAFM is a tuning fork based NC-AFM embedded in a 0.5 ml flow reactor, housed in a UHV system. The instrument operates from room temperature to 600 K and from UHV to 6 bar. A gas system mixes up to 5 gases and controls the flow and pressure, while a mass spectrometer is used for on-line analysis of the reaction products, enabling direct correlation of catalyst structure with reactivity. The force sensor is a miniature quartz tuning fork, which is mounted in the qPlus configuration and has a resonance frequency of 96 kHz. The micro-sized tip is grown by electron beam induced deposition and consist of polycrystalline Pt with carbon impurities. The design of the instrument and the challenges of NC-AFM at high pressure and high temperature conditions will be discussed. In addition, the performance of the instrument is characterized and images of single crystal samples and supported nanoparticles in catalytically relevant conditions will be shown.