Time：24th April, 2019, 3:00 - 4:30 pm
Venue：No.2 Room, Conference Center
Lecturer：Dr. Thomas Lunkenbein, Fritz-Haber-Institut der Max-Planck-Gesellschaft, Berlin, Germany
A heterogeneous catalyst is a metastable material. Similar to other solids heterogeneous catalysts exhibit a rich defect chemistry in their bulk and surface structures, which can modulate their catalytic performance. However, for prospective rational catalyst design, which also includes a sufficient long-term stability, the impact of such local structures on the catalytic turnover has to be fully understood. To achieve this goal an unprecedented insight into these structures on the local scale is required.
Although information on the bulk and surface structure can be obtained by integral methods, such as X-ray diffraction and/or X-ray photoelectron spectroscopy, important local deviations from the ideal structure may be overlooked. Nowadays, local insights can be obtained by modern transmission electron microscopes (TEM). Recent developments in the field of electron microscopy have rendered this technique as the tool to locally describe the nano- and mesoscale of heterogeneous catalysts also under working conditions.
In this lecture the local complexity in structure and composition of different heterogeneous catalysts will be addressed. It will be shown how heterogeneous a macroscopic homogeneous sample can be. In addition, the temporal evolution of such local structures during the catalytic reaction was tracked by ex situ, quasi in situ, and operando electron microscopy techniques implying the occurrence of structural and morphological changes on the atomic and mesoscale.
Dr. Thomas Lunkenbein is group leader for electron microscopy in the Department of Inorganic Chemistry (since 2018) of the Fritz-Haber-Institut der Max-Planck-Gesellschaft, where he is currently working on his habilitation. After he received his Ph.D. in Inorganic Chemistry from the University of Bayreuth in 2012 he joined the electron microscopy group of the Inorganic Chemistry Department of the Fritz-Haber-Institut der Max-Planck-Gesellschaft as a postdoc. He has obtained the Award of the Emil-Warburg-Foundation in (2013), the Cultural Award of Bavaria (2013) and was elected to the 30 most promising young chemists under 30 by American Scientific (2013). His research interests tackle the investigation of local structures and their temporal evolution in heterogeneous catalysts using different techniques of electron microscopy.
Contact: ZHAO Xu, DNL2002