The purified outer membrane bacterial protein OmcA binds densely to the surface of hematite (Fe2O3), permitting direct electron transfer to this solid mineral to reduce Fe (III) with an electron flux of about 1013 electrons /cm2/s. In the presence of hematite, there is a substantial increase in the amplitude of internal protein motions that correlate with metal reduction. Binding is highly favo...

Transient absorption spectroscopy on the μs-s time scale is used to monitor the yield and decay dynamics of photogenerated holes in nanocrystalline hematite photoanodes. In the absence of a positive applied bias, these holes are observed to undergo rapid electron-hole recombination. The application of a positive bias results in the generation of long-lived (3 ± 1 s lifetime) photoholes.

The soils at the Opportunity site are fine-grained basaltic sands mixed with dust and sulfate-rich outcrop debris. Hematite is concentrated in spherules eroded from the strata. Ongoing saltation exhumes the spherules and their fragments, concentrating them at the surface. Spherules emerge from soils coated, perhaps from subsurface cementation, by salts. Two types of vesicular clasts may represe...

We report the facile fabrication of three-dimensional (3D) silicon/hematite core/shell nanowire arrays decorated with gold nanoparticles (AuNPs) and their potential application for sunlight-driven solar water splitting. The hematite and AuNPs respectively play crucial catalytic and plasmonic photosensitization roles, while silicon absorbs visible light and generates high photocurrent. Under sim...

one of the most important methods to produce sponge iron is coal based reduction of iron ore. direct reduction methods based on coal are being improved due to the abundance of coal sources and its lower cost in comparison with natural gas. volatile materials in coal play an important role in the reduction of iron oxides. in this study, noncoking coal with high volatile materials from iran and c...

iron oxide (fe2o3) is widely used as a catalyst, pigment and gas sensitive material.  in this article, α-fe2o3 nano-rods were first synthesized via a simple chemical method using iron(iii) nitrate 9- hydrate (fe(no3)3.9h2o) as precursor. xrd pattern showed that the iron oxide nanoparticles exhibited alpha-fe2o3 (hematite) structure in nanocrystals. the single-phase α- fe2o3 nano-rods were prepa...

Traces of ferric oxide have a strong catalytic effect on both nucleation and growth phases of the transfornation of TiOz from anatase to rutile. This effect is greatly enhanced in atmospheres of low/6,. Using X-ray diffraction techniques, the kinetics of the phase transformation were studied at 1 atm. and 900 to 1000'Q for anatase mixed intimately with up to 0.2/s by weight hematite (Feroa) tn ...

It has been discovered that magnetite ( Fe304 ) is rapidly oxidized to hematite (o<-Fe 0 ), upon illumination ( X<.310p1 ) in an 02-bear~ni atmosphere. A laboratory investigation has been carried out to determine the kinetics and mechanism of this rapid oxidation process. It has been found that the process consists of a series of constituent reactions which are common to most oxidation mechanis...

Our understanding of subsurface microbiology is hindered by the inaccessibility of this environment, particularly when the hydrogeologic medium is contaminated with toxic substances. In this study, surrogate geological media contained in a porous receptacle were incubated in a well within the saturated zone of a pristine region of an aquifer to capture populations from the extant communities. A...