Solid oxide fuel cell (a) operation concept and (b) perovskite structure.DSC-TGA curve for Ba10CG and Ba40CG calcined at 900 °C.XRD patterns for (a) Ba10CG and (b) Ba40CG pellets sintered at 1400 °C.SEM images for (a) Ba10CG and (b) Ba40CG pellet sintered at 1400 °C.High resolution TEM images for BCG powder calcined at 900 °C.Energy dispersion spectra of BCG powder calcined at 900 °C.