Transient Oxygen States in Catalysis: Ammonia Oxidation at Ag(111)

Carley, Albert Frederick, Davies, Philip Rosser ORCID: https://orcid.org/0000-0003-4394-766X, Roberts, Meirion Wyn and Thomas, Kevin K. 2010. Transient Oxygen States in Catalysis: Ammonia Oxidation at Ag(111). Langmuir 26 (21) , pp. 16221-16225. 10.1021/la100953m

Full text not available from this repository.

Abstract

Although the reactive sticking probability of oxygen at Ag(111) is of the order of 10-6 at 295 K, ammonia oxidation is a facile process at low temperatures. A combination of quantitative analysis of photoelectron spectra together with high resolution electron energy loss spectroscopy provides kinetic and spectroscopic evidence for an ammonia-dioxygen complex, stable at 100 K, as the key intermediate. The reactive oxygen O2(s) is a transient dioxygen precursor of the unreactive peroxo state O2-(a). It is present as a complex when ammonia and dioxygen are coadsorbed at low temperature (100 K) with evidence from both O(1s) and energy loss spectra. Hydroxyl and amide/imide species are formed, followed by dehydroxylation and oxide formation at 260 K. This is a further example (zinc was the first) of how an sp-metal, where dioxygen bond cleavage is slow, provides an alternative pathway via a transient dioxygen state to catalytic oxidation through precursor assisted dioxygen bond cleavage. Whether it is a general characteristic of sp-metals remains to be established. Comparisons are made with the homogeneously catalyzed Gif reaction, the selective oxidation of hydrocarbons by dioxygen.

Item Type:	Article
Date Type:	Publication
Status:	Published
Schools:	Chemistry Cardiff Catalysis Institute (CCI) Neuroscience and Mental Health Research Institute (NMHRI)
Subjects:	Q Science > QD Chemistry
Publisher:	American Chemical Society
ISSN:	0743-7463
Last Modified:	18 Oct 2022 12:34
URI:	https://orca.cardiff.ac.uk/id/eprint/10328

Citation Data

Cited 5 times in Scopus. View in Scopus. Powered By Scopus® Data

Actions (repository staff only)

Edit Item