Iron oxides perovskite-type

Square Concentration Pulses in Oxidation Catalysis over Perovskite-type Oxides of Manganese and Iron... 

Oxide ratio, 18 815 Oxides, 16 598 acidic, 22 190-191 bond strengths and coordination numbers of, 22 570t diorganotin, 24 819 glass electrodes and, 14 28 gold, 22 707 iron, 14 541-542 lead, 14 786-788 manganese, 15 581-592 nickel, 27 106-108 niobium, 27 151 plutonium, 29 688-689 in perovskite-type electronic ceramics, 14 102... 

Well-ordered macroporous spinel-type and perovskite-type mixed iron oxide, Eai x Srx Ee03 and MFe204 (M = Ni, Zn, Co, Nii.x Zn ) can be prepared using a mixed metal nitrates solution in mixed solvent of EG and methanol.Ordered macroporous layered double... 

Extension of the microemulsion reaction method to complex oxides has been explored for a wide variety of materials, including aluminosilicate zeolite [45,108] ferrites [109], mullite [110], barium titanate [111,112], and various perovskite-type mixed oxides [112,113], yttrium-iron garnets (YIGs) [114,115], and high TV superconducting oxides [116-120]. 

Singh, S., Singh, A., Yadav, B.C, and Dwivedi, P.K. (2013) Fabrication of nanobeads structured perovskite type neodymium iron oxide film its structural, optical, electrical and LPG sensing investigations. Sens. Actuators B, 177, 730-739. 

Sadakane, M., Horiuchi, T Kato, N., Sasaki, K., and Ueda, W. (2010) Preparation of three-dimensionally ordered macroporous perovskite-type lanthanum-iron-oxide LaFeOs with tunable pore diameters high porosity and photonic property./. Solid State Chem., 183,1365-1371. 

Teraoka, T., Zhang, K.M., Okamoto, K., and Yamazoe, Y. Mixed ionic-electronic condnctivity of lanthanum strontium cobalt iron oxide (Lai cSr cCoi Fey03 ) perovskite-type oxides. Mater. Res. Bull. 1988, 23, 51-58. 

Titanium occurs in nature in the minerals rutile( Ti02), ilmenite (FeTiOs), geikielite, (MgTiOs) perovskite (CaTiOs) and titanite or sphene (CaTiSi04(0,0H,F)). It also is found in many iron ores. Abundance of titanium in the earth s crust is 0.565%. Titanium has been detected in moon rocks and meteorites. Titanium oxide has been detected in the spectra of M-type stars and interstellar space. 

Complex oxides of the perovskite structure containing rare earths like lanthanum have proved effective for oxidation of CO and hydrocarbons and for the decomposition of nitrogen oxides. These catalysts are cheaper alternatives than noble metals like platinum and rhodium which are used in automotive catalytic converters. The most effective catalysts are systems of the type Lai vSrvM03, where M = cobalt, manganese, iron, chromium, copper. Further, perovskites used as active phases in catalytic converters have to be stabilized on the rare earth containing washcoat layers. This then leads to an increase in rare earth content of a catalytic converter unit by factors up to ten compared to the three way catalyst. 

The role of support on the performance of noble metals-based catalysts for the total oxidation of aromatic hydrocarbons is essential [38]. Although with a smaller surface area than the typical supports, perovskites also demonstrate good properties as carriers for noble metals. Thus, perovskites of type LaBOs (B = Co, Mn, Fe, Ni) synthesized using the citrate route were used as support for noble metals in total oxidation of toluene [39]. The performances of these catalysts varied in the order Fe>Mn>Co>Ni, and the superior behavior of iron was attributed to the low temperature of calcination and the high stability of the perovskite lattice irrespective of the nature of the stream it was exposed to. The dispersion of palladium at the different stages of the process remained unchanged. 

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