A facile mixed complex synthesis method for perovskite oxides toward electrocatalytic oxygen reduction.

The perovskite-type La(0.5+x)Sr(0.5−x)FeO3−δ (x = 0.00, 0.10, 0.20) oxides for the electrocatalytic oxygen reduction reaction (ORR) were synthesized by a facile reaction-EDTA/citric acid mixed complex sol–gel method. The cubic single-phase perovskite structure of the as-prepared oxides is demonstrated using powder X-ray diffraction (XRD). Scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM–EDX), transmission electron microscopy/selected area electron diffraction (TEM–SAED), and X-ray photoelectron spectroscopy (XPS) characterizations were also conducted for the perovskite-type La(0.5+x)Sr(0.5−x)FeO3−δ (x = 0.00, 0.10, 0.20) oxides. Furthermore, the electrochemical ORR properties of the as-prepared oxides in alkaline media were studied, with the oxides exhibiting good electrocatalytic ORR performance. [ABSTRACT FROM AUTHOR]