Preparation of SrFeO∼2.85 perovskite using a citric acid assisted Pechini-type method

Nanocrystalline SrFeO∼2.85 perovskite was synthesized by a citric acid assisted sol-gel method. The synthesis procedure was optimized by systematically varying the pH, molar ratio of citric acid to total metal cations (Ra) and calcination temperature. The resulting effects on SrCO3 impurity, surface area and crystallite size were studied. The as-prepared SrFeO∼2.85 has been characterized by elemental analysis, X-ray diffraction (XRD), nitrogen adsorption isotherms (BET), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). These showed that the best conditions for preparing single phase nanocrystalline SrFeO∼2.85 perovskite powders employed pH < 5, Ra = 1.0 and a calcination temperature of 600 °C.