Dehydrogenation of Dodecahydro-N-ethylcarbazole on Pd/Al2O3 Model Catalysts

Journal article

Publication Details

Author(s): Sobota M, Nikiforidis I, Amende M, Sanmartίn Zanón B, Staudt T, Höfert O, Lykhach Y, Papp C, Hieringer W, Laurin M, Assenbaum D, Wasserscheid P, Steinrück HP, Görling A, Libuda J
Journal: Chemistry - A European Journal
Publisher: Wiley-VCH Verlag
Publication year: 2011
Volume: 17
Journal issue: 41
Pages range: 11542-11552
ISSN: 0947-6539


To elucidate the dehydrogenation mechanism of dodecahydro-N-ethylcarbazole (H-12-NEC) on supported Pd catalysts, we have performed a model study under ultra high vacuum (UHV) conditions. H-12-NEC and its final dehydrogenation product, N-ethylcarbazole (NEC), were deposited by physical vapor deposition (PVD) at temperatures between 120 K and 520 K onto a supported model catalyst, which consisted of Pd nanoparticles grown on a well-ordered alumina film on NiAl(110). Adsorption and thermally induced surface reactions were followed by infrared reflection absorption spectroscopy (IRAS) and high-resolution X-ray photoelectron spectroscopy (HR-XPS) in combination with density functional theory (DFT) calculations. It was shown that, at 120 K, H-12-NEC adsorbs molecularly both on the Al2O3/NiAl(110) support and on the Pd particles. Initial activation of the molecule occurs through C-H bond scission at the 8a- and 9a-positions of the carbazole skeleton at temperatures above 170 K. Dehydrogenation successively proceeds with increasing temperature. Around 350 K, breakage of one C-N bond occurs accompanied by further dehydrogenation of the carbon skeleton. The decomposition intermediates reside on the surface up to 500 K. At higher temperatures, further decay to small fragments and atomic species is observed. These species block most of the absorption sites on the Pd particles, but can be oxidatively removed by heating in oxygen at 600 K, fully restoring the original adsorption properties of the model catalyst.

FAU Authors / FAU Editors

Amende, Maximilian
Lehrstuhl für Physikalische Chemie II
Lehrstuhl für Theoretische Chemie
Görling, Andreas Prof. Dr.
Lehrstuhl für Theoretische Chemie
Hieringer, Wolfgang PD Dr.
Höfert, Oliver
Lehrstuhl für Physikalische Chemie II
Laurin, Mathias Dr.
Lehrstuhl für Physikalische Chemie II
Libuda, Jörg Prof. Dr.
Professur für Physikalische Chemie
Lykhach, Yaroslava
Lehrstuhl für Physikalische Chemie II
Nikiforidis, Ioannis
Lehrstuhl für Theoretische Chemie
Papp, Christian PD Dr.
Lehrstuhl für Physikalische Chemie II
Sobota, Marek
Graduiertenzentrum der FAU
Steinrück, Hans-Peter Prof. Dr.
Lehrstuhl für Physikalische Chemie II
Wasserscheid, Peter Prof. Dr.
Lehrstuhl für Chemische Reaktionstechnik

Additional Organisation
Exzellenz-Cluster Engineering of Advanced Materials

How to cite

Sobota, M., Nikiforidis, I., Amende, M., Sanmartίn Zanón, B., Staudt, T., Höfert, O.,... Libuda, J. (2011). Dehydrogenation of Dodecahydro-N-ethylcarbazole on Pd/Al2O3 Model Catalysts. Chemistry - A European Journal, 17(41), 11542-11552.

Sobota, Marek, et al. "Dehydrogenation of Dodecahydro-N-ethylcarbazole on Pd/Al2O3 Model Catalysts." Chemistry - A European Journal 17.41 (2011): 11542-11552.


Last updated on 2019-13-03 at 17:14