Structure-function relationship for alumina supported platinum during formation of ammonia from nitrogen oxide and hydrogen in presence of oxygen
Artikel i vetenskaplig tidskrift, 2016

We study the structure-function relationship of alumina supported platinum during forma- tion of ammonia from nitrogen oxide and dihydrogen by employing in situ X-ray absorption and Fourier transformed infrared spectroscopy. Particular focus is directed towards the effect of increased levels of oxygen on the reaction as a model system for emerging technologies for passive selective catalytic reduction of nitrogen oxides. The suppressed formation of ammo- nia observed as the feed becomes net-oxidizing is accompanied by a considerable increase in the oxidation state of platinum as well as enhanced formation of surface nitrates and loss of NH-containing surface species. In the presence of (excess) oxygen, the ammonia formation is proposed to be limited by the weak interaction between nitrogen oxide and the oxidized platinum surface. This leads to slow dissociation rate of nitrogen oxide and thus low abun- dance of atomic nitrogen surface species that can react with adsorbed hydrogen atoms. In this case the consumption of hydrogen through the competing water formation reaction and decomposition/oxidation of ammonia are of less importance for the net ammonia formation.

Författare

Emma Adams

Chalmers, Kemi och kemiteknik, Tillämpad kemi, Teknisk ytkemi

Kompetenscentrum katalys (KCK)

Lindsay R. Merte

Lunds universitet

Anders Hellman

Kompetenscentrum katalys (KCK)

Chalmers, Fysik, Kemisk fysik

Magnus Skoglundh

Kompetenscentrum katalys (KCK)

Chalmers, Kemi och kemiteknik, Tillämpad kemi, Teknisk ytkemi

Johan Gustafson

Lunds universitet

Eva Benedixen

Haldor Topsoe

Pär Gabrielsson

Haldor Topsoe

Florian Bertram

Lunds universitet

Jonas Evertsson

Lunds universitet

Chu Zhang

Lunds universitet

Stefan Carlson

Lunds universitet

Per-Anders Carlsson

Kompetenscentrum katalys (KCK)

Chalmers, Kemi och kemiteknik, Tillämpad kemi, Teknisk ytkemi

Physical Chemistry Chemical Physics

1463-9076 (ISSN) 1463-9084 (eISSN)

Vol. 18 16 10850-10855

Drivkrafter

Hållbar utveckling

Styrkeområden

Nanovetenskap och nanoteknik

Transport

Energi

Materialvetenskap

Ämneskategorier

Fysikalisk kemi

Kemiska processer

Atom- och molekylfysik och optik

Materialkemi

Den kondenserade materiens fysik

DOI

10.1039/C5CP07624B