Redox thermodynamics and phase composition in the system SrFeO3 − δ — SrMnO3 − δ
| Autor: | Christian Sattler, Josua Vieten, Martin Schmücker, Brendan Bulfin, Marion Senholdt, Martin Roeb |
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| Jazyk: | angličtina |
| Rok vydání: | 2017 |
| Předmět: |
Air separation
concentrated solar Radiation Chemistry Enthalpy perovskites Thermodynamics chemistry.chemical_element 02 engineering and technology General Chemistry 010402 general chemistry 021001 nanoscience & nanotechnology Condensed Matter Physics 01 natural sciences Redox Oxygen 0104 chemical sciences Phase composition General Materials Science Thermochemical Cycles 0210 nano-technology Chemical looping combustion Solid solution Perovskite (structure) |
| DOI: | 10.1016/j.ssi.2017.06.014 |
| Popis: | Perovskite oxides are considered promising redox materials for many fields of application, such as chemical looping processes for thermochemical air separation, oxygen pumping and fuel production, in particular considering a solar heat source. The large range of possible perovskite compositions can be extended by the synthesis of solid solutions between different perovskite phases. In this work, the solid solution formation in the system SrMn1 − xFexO3 − δ is evaluated, showing that SrFeO3 − δ and SrMnO3 − δ are miscible in any ratio investigated. Moreover, redox thermodynamics were studied using a van't Hoff approach. It has been found that in mixed manganese ferrite perovskites, the reduction of Fe4 + is preferred over the reduction of Mn4 +, leading to an increase in redox enthalpy and entropy when both species are reduced. Our findings allow the targeted synthesis of perovskites with superior redox properties for applications in chemical looping processes, as the redox thermodynamics are adjustable via variation of the Fe content. |
| Databáze: | OpenAIRE |
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