Understanding the effects of atomic structure modification in hematite photoanodes is essential for rational design high-efficiency functionalizations. Recently, it was found that interface with Sn/Sb segregates considerably increases photocatalytic efficiency. However, understanding different electronic these modifications at level still lacking. This Letter describes segregation two dopants–S...

To investigate the influence of the Morin transition on the photoelectrochemical (PEC) activity of hematite, electronic properties in different magnetic phases were studied on the basis of the first-principles calculations within the GGA+U approximation. The results show that the effective electron mass in the (0001) plane changes remarkably due to the spin−flop transition, while the effective ...

The volatile matter of non-coking coal was used for the reduction of hematite in argon atmosphere at nonisothermal condition. A thermal gravimeter furnace enable to use an 80 mm-height crucible was designed for the experiments to measure the weight changes of about 10 grams samples. A two-layered array of coal and alumina and four-layered array of iron oxide, alumina, coal and alumina was u...

Fe16N2 fine particles were prepared by reduction in 5% H2/Ar gas mixture flow, starting from goethite or hematite precursors, followed by nitridation in ammonia gas flow. Small amounts of metallic iron and iron oxide are present besides the main phase which is an ordered iron nitride having martensite structure (α ’’ -Fe16N2) as revealed by Mössbauer spectroscopy measurements. However, X-ray di...

Iron oxides in nature take on different forms. „The most common iron oxide is hematite, Fe2O3, which is the end product of many geological processes and the main source of iron for our civilization,“ explains Bykova. During the past five years, however, scientists have discovered other iron oxides like Fe4O5, Fe5O6, and Fe13O19 that form at high pressures and temperatures. Investigating the beh...

Mixed nano iron oxides powder containing goethite (α-FeOOH), hematite (α-Fe(2)O(3)) and ferrihydrite (Fe(5)HO(8)·4H(2)O) was synthesized through surfactant mediation-precipitation route using cetyltrimethyl ammonium bromide (CTAB). The X-ray diffraction, FTIR, TEM, Mössbauer spectroscopy were employed to characterize the sample. These studies confirmed the nano powder contained 77% goethite, 9%...

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...