About active sites in heterogeneous catalysts

You are cordially invited to the seminar of the Department of Nanocatalysis to be presented by Prof. Jeroen van Bokhoven of ETH Zurich and PSI Villigen in the Brdicka Lecture Hall at 10 am on Wednesday, September 4, 2019.

Abstract:

Heterogeneous catalysts are essential and widely applied in the production of fuels and chemicals and in pollution abatement. Despite their widespread use, the molecular level description of the catalytic process remains poor. One of the reasons is the difficulty to identify the structure of the ensemble of atoms that constitute the active site, being the minority of species and / or being short-lived. In situ and especially operando characterization, determining structure and performance simultaneously, has become the standard. However, even under operando conditions it remains very difficult if not impossible to quantify the number of active sites and their structure.

In beneficial cases, transient and time-resolved structural measurements enable the identification of active sites. In other cases, quantitative relations between a certain species and catalytic activity has been established. Because of the essential role of characterization in the time-domain, development and application of time-resolved x-ray and x-ray photoemission spectroscopies will be described. From such measurements, the need for relevant pressures during measurement, thus in situ, becomes clear.

References

René Kopelent, Jeroen A. van Bokhoven, Jakub Szlachetko, Jacinta Edebeli, Cristina Paun, Maarten Nachtegaal and Olga V. Safonova, Angewandte Chemie. Int. Ed. 54 (2015) 8728-8731

Simon A. Kondrat and Jeroen A. van Bokhoven, Topics in Catalysis (2018), https://doi.org/10.1007/s11244-018-1057-4 Simon A. Kondrat et al. Nature 531 (2016) 83

Luca Artiglia, Fabrizio Orlando, Kanak Roy, René Kopelent, Olga Safonova, Maarten Nachtegaal, Thomas Huthwelker and Jeroen A. van Bokhoven The Journal of Physical Chemistry Letters 8 (2017) 102-108.