Fig. 1: Structural evolution of SrFe0.5Co0.5O2.5 (SFCO) during thermal reduction.
From: Selective reduction in epitaxial SrFe0.5Co0.5O2.5 and its reversibility
a Schematic of the reduction process in brownmillerite SFCO thin films on (001) SrTiO3 via annealing in 3% H2/Ar forming gas. Green, red, blue, and grey spheres represent Sr, Fe/Co, Ti, and O atoms, respectively. b X-ray diffraction patterns of as-grown and reduced SFCO films. c Out-of-plane lattice constants as a function of annealing temperature (1 h fixed). d Out-of-plane lattice constants as a function of annealing time at 400 °C. Blue and yellow background regions indicate the brownmillerite phase and the oxygen-deficient perovskite phase, respectively, emphasising the temperature range (300–400 °C) where the structural transition occurs.
