Synthesis and theoretical investigation of brown millerite oxide CaSrFe₂O₅

Brown millerite oxides form a special class of materials that possesses the ABO_2.5 stoichiometry, where they can be thought to be derived from the ABO₃ perovskite oxides by replacing 1/6 of oxygen ions by vacancies. Brown millerites are promising material for energy and environmental applications such as fuel cells, CO₂ capture, batteries, H₂ production and supercapacitors. Herein, we synthesized brown millerite oxide CaSrFe₂O₅ by solid-state reaction method. The analysis of observed P-XRD indicated the formation of a single phase brown millerite oxide that is similar to the structure of Ca₂Fe₂O₅ (JCPDS PDF - 46-0478). Rietveld refinement for the structure of CaSrFe₂O₅ also confirmed the single phase formation of the CaSrFe₂O₅ and refined profile parameter shown in the article. Theoretical investigation of CaSrFe₂O₅ showed that antiferomagnetic (AFM) is the magnetic ground state as shown herein. Density of states (DOS) plot showed O 2p and Fe 3d orbitals are the main constitute from which valence and conduction band are formed, mirror image of states in spin up and down channel confirmed the AFM magnetic ground state of CaSrFe₂O₅