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Evolution of Fe species during the synthesis of over-exchanged Fe/ZSM5 obtained by chemical vapor deposition of FeCl3

“…This could be the reason for the differences between the results obtained in this study and those presented on the calcined Fe/ZSM5 by Marturano et al [21]. In their EXAFS study a calcined Fe/ZSM5 sample was measured after flushing He at 400 • C. The reactivity of oxygen in Fe/ZSM5 will be discussed by our group in detail elsewhere [65]. It should be noted that the results of the EXAFS fitting presented in this work for the sample Fe/ZSM5-17-sc (Table 6) are different from those presented by our group on the same sample in a previous report [19].…”

“…This model is based on results obtained by characterization with H 2 and CO TPR, XRD, FTIR, and EPR. X-ray absorption fine structure spectroscopy (XAFS) studies performed independently by our group [19] and by Marturano et al [20,21] confirmed the presence of Fe binuclear oxo-hydroxo clusters in the over-exchanged Fe/ZSM5 obtained through CVD. Nevertheless, binuclear complexes are not the only Fe species present in over-exchanged Fe/ZSM5.…”

“…In their EXAFS study a calcined Fe/ZSM5 sample was measured after flushing He at 400 • C. The reactivity of oxygen in Fe/ZSM5 will be discussed by our group in detail elsewhere [65]. It should be noted that the results of the EXAFS fitting presented in this work for the sample Fe/ZSM5-17-sc (Table 6) are different from those presented by our group on the same sample in a previous report [19]. Significant differences are present in the results of the fitting of both the Fe-O and the Fe-Fe contributions.…”

“…Several characterization studies have been performed in order to unravel the nature of the active phase [1,2,11,12,[18][19][20][21][22][23]. Binuclear iron oxo-hydroxo clusters at the ion exchange positions of the ZSM5 lattice have been proposed earlier as the active phase for both the HC-SCR of NO [1,2,18] and the catalytic decomposition of N 2 O [12].…”

In-Situ Soft X-ray Absorption of Over-exchanged Fe/ZSM5

“…This additional study will show that the application of in-situ soft X-ray spectroscopy can give relevant information about the catalytic active Fe sites. Details about the sample preparation were described earlier by Battiston et al 18 Almost all Brønsted acid sites were removed from the H/ZSM5, considering that the H + removal efficiency value of 0.98. Inductively coupled plasma (ICP) analysis was performed to determine the Si/Al ratio (Si/Al ) 17.0) and the iron loading (Fe/Al ) 0.97) of the starting Fe/ZSM5 sample.…”