Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
9610094 | Catalysis Today | 2005 | 8 Pages |
Abstract
The spin state of iron ions in Fe-ZSM-5 zeolites can be purposefully varied by adsorption of gaseous probe molecules. The resulting Fe complexes with half-integer spin (S=12, S=32 and S=52) can be reliably identified by electron paramagnetic resonance (EPR). A good correlation has been found between the concentration of surface sites active in low-temperature nitrous oxide decomposition and the concentration of low-spin (S=12) nitrosyl complexes of Fe formed after adsorption of NO molecules. Based on the analysis of the formation of such complexes under varying conditions, we conclude that these active sites contain a binuclear iron complex with SÂ =Â 0 and three adsorbed NO molecules. An approach to investigate various Fe-containing sites in oxidation catalysts is discussed.
Related Topics
Physical Sciences and Engineering
Chemical Engineering
Catalysis
Authors
A.M. Volodin, G.M. Zhidomirov, K.A. Dubkov, E.J.M. Hensen, R.A. van Santen,