Interaction of NO2 with model NSR catalysts: metal-oxide interaction controls initial NOx storage mechanism.
Using scanning tunneling microscopy (STM), molecular-beam (MB) methods and time-resolved infrared reflection absorption spectroscopy (TR-IRAS), we investigate the mechanism of initial NO(x) uptake on a model nitrogen storage and reduction (NSR) catalyst. The model system is prepared by co-deposition of Pd metal particles and Ba-containing oxide particles onto an ordered alumina film on NiAl(110). We show that the metal-oxide interaction between the active noble metal particles and the NO(x) storage compound in NSR model catalysts plays an important role in the reaction mechanism. We suggest that strong interaction facilitates reverse spillover of activated oxygen species from the NO(x) storage compound to the metal. This process leads to partial oxidation of the metal nanoparticles and simultaneous stabilization of the surface nitrite intermediate.
Desikusumastuti
Aine
A
Lehrstuhl für Physikalische Chemie II, Universität Erlangen-Nürnberg, Erlangen, Germany.
Staudt
Thorsten
T
Qin
Zhihui
Z
Happel
Markus
M
Laurin
Mathias
M
Lykhach
Yaroslava
Y
Shaikhutdinov
Shamil
S
Rohr
Friedemann
F
Libuda
Jörg
J