The basic building units of brownmillerite-type A2B2O5 structures are perovskite-like layers of corner-sharing BO6 octahedra and zweier single chains of BO4 tetrahedra. A three-dimensional framework is formed by alternate stacking of octahedral layers and sheets of tetrahedral chains. The compound Ca2Fe2O5 is known to have Pnma symmetry at ambient conditions. The space group Imma was reported t...

For comparison with the Mn/Mn oxoperovskites at the crossover from localized to itinerant behavior of the s-bonding e electrons, the electronic properties of three oxygen non-stoichiometric, mixed-valent Fe/Fe oxoperovskites were explored by measuring their resistivity r(T), thermoelectric power a(T), and magnetic susceptibility w(T). Oxidation of Ca2Fe2O5 by annealing in ozone progresses by ox...

AbstractESW as a natural byproduct, although non-hazardous and contains calcium, magnesium carbonate and protein, is commonly disposed in landfills without any pretreatment because it was traditionally useless. In this regards, we wish to report the synthesis of a novel CaO/Ca2Fe2O5 nanocomposite based on ESW. At the first, eggshell (ES) nanopowder was prepared by ball-milling. Then, the ...

Coal ash is one of the significant factors for operating efficiency pressurized coal chemical looping gasification (CLG). To explore influence mechanism physical deposition and combination on iron-based oxygen carrier (OC) under conditions, effects content, components pressure reduction performance Fe2O3/Al2O3 OC are investigated. The micro-structure phase transformation particles conditions ch...