This paper reports experimental results on the low-temperature (<100 oC) 18O and  2H fractionation of goethite (hematite)-water in a closed system. Both goethite (-FeOOH) and hematite (-Fe2O3) exhibited closer fractionation factor values but the Hematite-Water value is slightly higher (~0.9932) than the Goethite-Water (~0.9924) for the 18O isotope. The average fractionation factor (1000ln...

The exposed surface facets play an important role in determining the catalytic performance of nanostructured materials. In this study, we report the synthesis of hematite nanoparticles with three varying morphologies with exposure of well-controlled {104}, {113} and {001} surfaces. The better shape control of hematite particles has provided a direct correlation between the surface facets and th...

Titanium oxide (TiO2) and iron oxide (α-Fe2O3) hematite films have potential applications as photoanodes in electrochemical water splitting. In the present work TiO2 and α-Fe2O3 thin films were prepared by two methods, e.g., sol-gel and High Power Impulse Magnetron Sputtering (HiPIMS) and judged on the basis of physical properties such as crystalline structure and surface topography and functio...

*Correspondence: Ondra Sracek, Department of Geology, Faculty of Science, Palacký University in Olomouc, 17. Listopadu 1192/12, 771 46 Olomouc, Czech Republic e-mail: [email protected] Mine tailings in African countries Zambia and Namibia have been investigated with an objective to determine the role of secondary hematite in immobilization of contaminants. Two sites, Chambishi and Mindolo, are ...

-The formation of hematite from amorphous Fe(III)hydroxide in aqueous systems at pH 6 and 70~ both with and without oxalate, was followed by kinetic measurements, electron microscopy, i.r. spectroscopy and thermal analysis. In the absence of oxalate, small amorphous particles coalesce into aggregates which eventually become single crystals of hematite. When oxalate is present, crystal growth is...

A unique modification of a hematite photoanode with perfluorinated Co-phthalocyanine (CoFPc) by strong binding associated with hydrophobic interaction is demonstrated. The resultant molecular electrocatalyst - a hematite photoanode hybrid material showed a significant onset shift and high stability for the photoelectrochemical oxidation evolution reaction (OER).

Nitrate is often found to be associated with atmospheric particles. Surface nitrate can change the hygroscopicity of these particles, and thus impact their chemical reactivity. However, the influence of nitrate on heterogeneous reactions of atmospheric trace gases is poorly understood. In this work, the effects of nitrate on heterogeneous conversion of SO2 with hematite at 298 K are investigate...

The rate of reaction of hematite with quinones and the quinone moieties of larger molecules may be an important factor in limiting the rate of reductive dissolution of hematite, especially by iron-reducing bacteria. It is possible that the rate of reductive dissolution of hematite in the presence of excess hydroquinone at pH 2.5 may be limited by the electron-transfer rate. Here, a reductive di...

INTRODUCTION The 2.0 Ga iron-bearing Gunflint Formation was deposited during a transitionary period in Earth history when a stable oxic atmosphere was being established. The Animikie Group, which comprises both the Rove and Gunflint Formations, extends NE-SW for approximately 175 km from Thunder Bay, Ontario to northern Minnesota [1]. The thickness of the Gunflint ranges from 100 to 180 m, with...

The impact on U(VI) adsorbed to lepidocrocite (γ-FeOOH) and hematite (α-Fe2O3) was assessed when exposed to aqueous sulfide (S(-II)aq) at pH 8.0. With both minerals, competition between S(-II) and U(VI) for surface sites caused instantaneous release of adsorbed U(VI). Compared to lepidocrocite, consumption of S(-II)aq proceeded slower with hematite, but yielded maximum dissolved U concentration...