Transition Metal Oxide-Based Perovskite Structures as a Bifunctional Oxygen Electrocatalysts: Fe Doped LaCoO3 Nanoparticles

Abstract

In this report, we have investigated lanthanum cobalt iron (LaCo1-xFexO3) perovskite nanoparticles synthesized by combining metallic nitrates, deionized water, and citric acid by using sol-gel method and subsequently calcinated at 400 °C for 1h and 900 °C for 7h, respectively. The formation of single-phase perovskite structure is a series of LaCo1-xFexO3 (x = 0, 0.2, 0.4, 0.6, 0.8, 1). The crystal structure, mean particle, and morphology properties of the prepared LaCo1-xFexO3 perovskite oxide nanoparticles were examined by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM). The perovskite structure has shown special performance for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) catalytic activity in alkaline medium. As the combined valence transition metal oxides are rising capable candidates for bifunctional electrocatalysts, the electrochemical performance of the LaCo1-xFexO3 catalyst was thoroughly investigated. Koutecky-Levich results on the ORR polarization curves of all compounds shows that the four-electron pathway is favorable on these perovskite oxides. In this paper, we report B-site Fe doping in perovskite structure is a sufficient strategy to improve ORR and OER catalytic activity for application in metal-air batteries.