Perovskite Sr_0.9Y_0.1CoO_3−δ Nanorods Modified with CoO Nanoparticles as a Bifunctional Catalyst for Rechargeable Li–O₂ Batteries

For practical application of lithium–oxygen batteries, one of the challenges is the development of efficient bifunctional electrocatalysts for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) in cathode. In this work, perovskite Sr0.9Y0.1CoO3−δ nanorods are synthesized by an electrospinning method. The performance of the Li–O2 cell with Sr0.9Y0.1CoO3−δ catalysts is better than that of the cell only with Super-P. Furthermore, modification of CoO nanoparticles on the cathode can provide an obviously improved electrochemical performance with a reduced voltage gap (∼80–140 mV), which is ascribed to the superior catalytic activity of CoO nanoparticles toward OER. All of these results demonstrate that the perovskite Sr0.9Y0.1CoO3−δ is an efficient bifunctional electrocatalyst for lithium–oxygen batteries, and the incorporation of CoO nanoparticles is an effective approach for improving the cathode performance as well