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

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 (2011)

Publication Type: Journal article

Publication year: 2011


Original Authors: Sobota M., Nikiforidis I., Amende M., Zanon B.S., Staudt T., Höfert O., Lykhach Y., Papp C., Hieringer W., Laurin M., Assenbaum D., Wasserscheid P., Steinrück H.-P., Görling A., Libuda J.

Publisher: Wiley-VCH Verlag

Book Volume: 17

Pages Range: 11542-11552

Journal Issue: 41

DOI: 10.1002/chem.201101311


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.

Authors with CRIS profile

Additional Organisation(s)

Related research project(s)

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.

BibTeX: Download