Aluminum-doped strontium ferrites for a two-step solar thermochemical air separation cycle: Thermodynamic characterization and cycle analysis

•Al-doped SrFeO3−δ perovskites for solar air separation, N2 production.•Samples synthesized using sol-gel method and structures confirmed by XRD.•Compound energy formalism reaction model vs. Al-percent, temperature, O2 pressure.•Sublattice interaction terms integral to capturing redox behavior.•0.6 mol of 99% purity N2 predicted per mol perovskite at a 4.0% cycle efficiency.