The need for studying catalyst under realistic conditions is emphasized both by academic and industrial research. Acquiring highly resolved local information from materials under realistic environments by means of Transmission Electron Microscopy (TEM) has been found to be essential in connecting microscopic and macroscopic properties of materials, e.g. relating catalytic performance with crystal structure and morphology. This study presents extensive characterization of NiGa and CuNi alloys during catalyst formation, alcohol synthesis, and accelerated aging experiments. The characterization platform consists of three complimentary in situ techniques: (1) Activity measurements based on a reactor connected to a gas chromatograph (GC), (2) In situ x-ray diffractometer (XRD) measurements based on a reactor cell connected to a mass spectrometer (MS), and (3) environmental TEM (ETEM) that allows for observation in a gaseous environment. By using heating holders, dynamic information about catalysts in their working state can be gained using a variety of TEM techniques. The presented platform successfully illustrates the capability of correlating the dynamic changes in structural phase and particle size distribution, measured both macroscopically (XRD) and microscopically (ETEM), with the catalytic activity.
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Scandem 2012 - Annual Meeting of the Nordic Microscopy Society