Experimental and theoretical characterization of NOx species on Ag/alpha-Al2O3
Artikel i vetenskaplig tidskrift, 2009

The adsorption of NO, species on alpha-alumina and Ag/alpha-alumina is investigated by in situ diffuse reflection infrared Fourier transform (DRIFT) spectroscopy and density functional theory (DFT) calculations. The vibrational spectra obtained by DRIFTS experiments show broad spectral bands In the range between 1650 and 1200 cm(-1). The absence of distinct features is attributed to the heterogeneity of powder samples, i.e, variation in Ag cluster size and alpha-alumina surface termination. DFT calculations are employed to evaluate ground-stale structures and vibrational wavenumbers of different NOx species adsorbed either on alumina or Ag-1-Ag-4 clusters supported on alumina In agreement with experiments, Ag cluster size and surface termination strongly Influence the calculated vibrational properties Although, an unambiguous identification of surface species from the DRIFT spectra IS difficult. the theoretical results provide valuable guidance As such, this approach has the potential to further increase the understanding of the reaction mechanism during hydrocarbon assisted selective catalytic reduction (HC-SCR) of NOx. (C) 2009 Elsevier B.V. All rights reserved.

selective catalytic-reduction

vibrational spectroscopy

in-situ ftir

adsorption

NOx surface species

hc-scr

Ag/Al2O3

1st principles

alumina surfaces

storage

nitrates

mechanistic aspects

DFT

DRIFT

Författare

Hanna Härelind

Kompetenscentrum katalys (KCK)

Chalmers, Kemi- och bioteknik, Teknisk ytkemi

Anders Hellman

Kompetenscentrum katalys (KCK)

Chalmers, Teknisk fysik, Kemisk fysik

Hannes Kannisto

Chalmers, Kemi- och bioteknik, Teknisk ytkemi

Kompetenscentrum katalys (KCK)

Henrik Grönbeck

Chalmers, Teknisk fysik, Kemisk fysik

Kompetenscentrum katalys (KCK)

Journal of Molecular Catalysis A: Chemical

1381-1169 (ISSN)

Vol. 314 102-109

Drivkrafter

Hållbar utveckling

Styrkeområden

Nanovetenskap och nanoteknik

Transport

Energi

Materialvetenskap

Ämneskategorier

Kemiska processer

DOI

10.1016/j.molcata.2009.08.022