“…In our previous work, through a high-throughput approach, we discovered the novel composition of Sr 0.75 Ba 0.25 Fe 0.875 Mg 0.125 O 3−δ , which has shown the potential of being an alternative material for CLAS under such conditions. 27 In this work, we extend the database on Ba-substituted perovskite oxides by investigating the performance of Sr 0.75 Ba 0.25 FeO 3−δ (SBF628), Sr 0.75 Ba 0.25 Fe 0.875 Mg 0.125 O 3−δ (SBFM6271), and Sr 0.25 Ba 0.75 FeO 3−δ (SBF268) for CLAS applications at low temperatures (400−700 °C) and relatively high partial oxygen pressures (0.2−0.01 atm O 2 ). In this study, we aim to understand the effects of Ba and Ba/Mg substitution on their redox properties for CLAS through an extensive thermodynamic analysis and evaluation of crystalline phases via Rietveld refinement.…”