The bifunctional electrocatalytic activity of perovskite La_0.6Sr_0.4CoO_3-δ for oxygen reduction and evolution reactions

Perovskite La_0.6Sr_0.4CoO_3-δ was synthesized by the Pechini method at different synthetic conditions and examined as a bi-functional catalyst for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). As the calcination temperature increases, the particle size and purity of the La_0.6Sr_0.4CoO_3-δ increases, indicating the formation of highly pure La_0.6Sr_0.4CoO_3-δ at higher calcination temperatures. The specific surface area of the perovskite oxides is increased by ball milling, which shows the improvement of the electrocatalytic activity. The electrocatalytic activities of all the prepared La_0.6Sr_0.4CoO_3-δ are much better than that of Ketjen black. The catalytic activity of the La_0.6Sr_0.4CoO_3-δ for both ORR and OER was systematically studied by combining their structural and electrochemical properties. The La_0.6Sr_0.4CoO_3-δ was then employed as an air cathode catalyst in a lithium-air battery to investigate the battery performance.