Binding Energy of Carbon Implanted into Hematite and in situ Observation of Reaction Behavior during Heating Up Experiment

Abstract

It is widely known that the direct contact between solid carbon and iron oxide shows quite a fast reduction rate in comparison with CO gas reduction. However, it is difficult to sustain the physical contact between solid carbon and iron oxide. Furthermore, the contact mode will be different from the production method, which will affect the reaction kinetics strongly.In this study, different kinds of contacts between solid carbon and hematite were made to clarify the reaction mechanism. One contact mode is the deposition of the carbon layer on the hematite surface using a vacuum evaporation method. Another method is the implantation of carbon ions into hematite. Using XPS (X-ray photoelectron spectroscopy), the binding energy of Fe-O-C was measured. Heating under an argon atmosphere was carried out. Both samples showed quite different reaction behavior, though the temperature at the beginning of the reduction reaction was almost the same. From these results, it was determined that the position of carbon will change the reaction behavior drastically, because it is important how the CO gas escapes from the reaction site.

Fe-loaded zeolites as catalysts in the formation of humic substance-like darkcoloured polymers in polycondensation reactions of humic precursors

“…2. The BEs of Fe(2p 3/2 ) for Z, Fe-Z-1 and Fe-Z-10 were determined to be 712.5, 712.0 and 711.2 eV, respectively, being higher than the BEs for hematite reported previously (710.0 eV) (Kashiwaya et al, 2011). In addition, the BEs of Fe(2p 3/2 ) for Fe(III) ionic species that are adsorbed to the cationexchange sites on the zeolite are reported to be in the range 711.6À712.5 eV, while the BEs for Fe(II) ionic species are 709.9À710.4 eV (Duxiao et al, 2001).…”