Experimental and theoretical characterization of NOx species on Ag/alpha-Al2O3
Journal article, 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.

Ag/Al2O3

DRIFT

storage

hc-scr

alumina surfaces

DFT

vibrational spectroscopy

nitrates

NOx surface species

in-situ ftir

1st principles

selective catalytic-reduction

mechanistic aspects

adsorption

Author

Hanna Härelind Ingelsten

Chalmers, Chemical and Biological Engineering, Applied Surface Chemistry

Competence Centre for Catalysis (KCK)

Anders Hellman

Competence Centre for Catalysis (KCK)

Chalmers, Applied Physics, Chemical Physics

Hannes Kannisto

Competence Centre for Catalysis (KCK)

Chalmers, Chemical and Biological Engineering, Applied Surface Chemistry

Henrik Grönbeck

Competence Centre for Catalysis (KCK)

Chalmers, Applied Physics, Chemical Physics

Journal of Molecular Catalysis A: Chemical

1381-1169 (ISSN)

Vol. 314 1-2 102-109

Driving Forces

Sustainable development

Areas of Advance

Nanoscience and Nanotechnology (2010-2017)

Transport

Energy

Materials Science

Subject Categories

Chemical Process Engineering

DOI

10.1016/j.molcata.2009.08.022

More information

Latest update

11/5/2018