Heterogeneous Cu-Fe oxide catalysts for preferential CO oxidation (PROX) in H-rich process streams.

The influence of Fe loading in Cu-Fe phases and its effect on carbon monoxide (CO) oxidation in H-rich reactant streams were investigated with the catalyst material phases characterized by Field Emission Scanning Electron Microscopy (FESEM), X-ray diffraction (XRD) studies and Mössbauer Spectroscopy (MS). There was no change in the oxidation state of the Fe ions with copper or iron loading. The catalytic activity was examined in the feed consisting of H, HO and CO for the preferential CO oxidation (PROX) process.

Local increase of the Curie temperature in Mn/Fe implanted YFeO (YIG).

The change in the Curie temperature of single crystalline garnet YFeO (YIG) sample due to lattice damage induced by ion implantation has been investigated in Fe emission Mössbauer Spectroscopy (eMS) following implantation of Mn (T = 1.5 min). The Mössbauer spectra analysis reveal high spin Fe ions substituted on both the octahedral and the tetrahedral sites.

The effect of oxidant species on direct, non-syngas conversion of methane to methanol over an FePO catalyst material.

The effect of the phase transformation of a FePO catalyst material from the tridymite-like (tdm) FePO to the α-domain (α-Fe(PO)) during the direct selective oxidation of methane to methanol was studied using oxidant species O, HO and NO. The main reaction products were CHOH, carbon dioxide and carbon monoxide, whereas formaldehyde was produced in rather minute amounts. Results showed that the single-step non-syngas activation of CH to oxygenate(s) on a solid FePO phase-specific catalyst was influenced by the nature of the oxidizer used for the CH turnover.

Atomic-scale study of the amorphous-to-crystalline phase transition mechanism in GeTe thin films.

The underlying mechanism driving the structural amorphous-to-crystalline transition in Group VI chalcogenides is still a matter of debate even in the simplest GeTe system. We exploit the extreme sensitivity of Fe emission Mössbauer spectroscopy, following dilute implantation of Mn (T½ = 1.5 min) at ISOLDE/CERN, to study the electronic charge distribution in the immediate vicinity of the Fe probe substituting Ge (Fe), and to interrogate the local environment of Fe over the amorphous-crystalline phase transition in GeTe thin films.