Iron oxides macroporous

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... 

Two-step adsorption kinetics of metd cations at iron oxides has been observed for several metals (26-28) and mainly attributed to interaction of the metal cations with different sites of the metal oxide surface (29). Diffusion of cations into micro- or macropores can be ruled out for synthetic goethites (30) due to an essential lack of porosity as determined by t-plot analysis (31). However, diffusion processes may be important for other oxides, especially amorphous iron oxides or oxides with certain coatings and oxide surfaces which have been subject to substantial dissolution processes. Thus, other processes than diffusion must have caused the two different kinetic domains of Fe(II) sorption to iron oxide surfaces. 

To overcome the stability problem, it is obvious that an alternative approach to material synthesis would be needed. In this respect a recent report suggested that iron oxide encapsulated in meso- and macroporous carbon can be used as anode in Li batteries and reaches a greatly improved reversibility and rate performance. At the same time, a similar structure for a cathode material based on iron and lithium fluoride was synthesized and investigated. It was demonstrated that encapsulation of transition metal-metal fluoride in nanocarbon might be an effective strategy to improve the cycling performance of such a cathode material. ... 

Taleb Khaled, Markovski Jasmina, MUosavljevic MUutin, et al. Efficient arsenic removal by cross-linked macroporous polymer impregnated with hydrous iron oxide Material performance. Chem. Eng. J. 279 (2015) 66—78. 

Takahashi, C., and Ueda, W. (2007) Facile pr aration of three-dimensionally ordered macroporous alumina, iron oxide, chromium oxide, manganese oxide, and their mixed-metal oxides with high porosity. Chem. Mater., 19,5779-5785. 

Sadakane, M., Takahashi, C, Kato, N., Asamuma, T., Ogihara, H., and Ueda, W. (2006) Three-dimensionally ordered macroporous mixed iron oxide preparation and structural characterization of inverse opals with skeleton structure. Chem. Lett, 35, 480-481. 

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. 

Well-ordered macroporous Fc203 can be prepared by using iron oxa-late. " Iron oxalate is soluble in ethanol-water mixed solvents, which can infiltrate the voids of templates. Iron oxalate can be converted to Fc203 without melting to form well-ordered macroporous material. If the oxalate salts are not soluble in alcoholic solution, oxalate or oxalate derivatives can be produced in the voids by a two-step method or an in situ method. In the two-step method, nitrate or acetate salts of Mn, Co or Ni infiltrate the voids and then react with oxalic acid to form oxalate salts in the voids. These oxalate salts can be converted to oxide by calcina-In the in situ method, nitrate of Mn or Fe is dissolved in EG-methanol solution, and the solution infiltrates the voids of templates. By heating the solution, EG is oxidised by nitrate to form metal oxalate derivatives. The metal oxalate derivatives can be converted to metal oxides. 

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