Enhanced electrocatalytic activity of three-dimensionally-ordered macroporous La0.6Sr0.4CoO3−δ perovskite oxide for Li–O2 battery application

Abstract

Three-dimensionally-ordered macroporous perovskite La_0.6Sr_0.4CoO_3−δ (3DOM LSC) structures were synthesized using polymethyl methacrylate (PMMA) templates prepared with different techniques. The electrocatalytic activity of the prepared 3DOM LSC perovskites was examined for both the oxygen reaction (ORR) and oxygen evolution reaction (OER) using various electrochemical techniques in both aqueous and nonaqueous electrolyte solutions. The discharge capacity and cycle performance were also investigated with a lithium–air battery fabricated with the 3DOM LSC perovskite catalysts. It was found that the electrochemical study in both aqueous and nonaqueous electrolyte solutions and the performance measurement in the lithium–air battery exhibit a similar electrocatalytic activity in the order of Centrifuge LSC1000 > Pellet LSC1000 > Powder LSC1000. The best performance of a lithium–air battery is observed from Centrifuge LSC1000. The enhanced catalytic performance of the 3DOM structures could be reasonably attributed to the formation of porous structures with increased surface area and catalytic activity, which facilitate the fast reversible formation and decomposition of Li₂O₂ as well as quick transportation of lithium ions and oxygen in the lithium air cell.