We investigated the effect of reductants over Fe-MFI catalysts (Fe-MFI) based on the catalytic performance in N
2O reduction in the absence of oxygen. The TOFs of N
2O decomposition and N
2O reduction by various reductants (H
2,CO, CH
4)increased with increasing Fe/Al ratio (Fe/Al≥0.15). As the result of extended X-ray absorption fine structure (EXAFS) analysis, only mononuclear Fe species were observed over Fe(0.10)-MFI after N
2O or O
2 treatment. On the other hand, binuclear Fe species were also observed over Fe(0.40)-MFI after treatment with N
2O. More reducible Fe species, which gave lower-temperature O
2 desorption, can be due to Fe binuclear species. Since the N
2O reduction with reductants proceeds via a redox mechanism, the reducible binuclear Fe species can exhibit higher activity than the mononuclear one. Furthermore, CH
4 can be oxidized under the presence of N
2O more easily than can H
2 and CO, although it is generally known that the reactivity of methane is very low.
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