Orthorhombically distorted perovskite SeZnO3 nanosheets as an electrocatalyst for lithium-oxygen batteries

Abstract

Perovskite ABO(3) provides higher catalytic activity than binary metal oxides owing to crystallographic defects and oxygen vacancies due to the multivalence of the A and B cations. In this study, perovskite SeZnO3 nanosheets were synthesized via a simple wet chemistry method with sodium dodecyl sulfate as the surfactant. Material surface analysis using 0 1s X-ray photo-electron spectroscopy confirmed an O-vacancy concentration of 50%, confirming the presence of large amounts of defects on the surface of the SeZnO3 nanosheets. The lithium-oxygen batteries with SeZnO3 nanosheet as an oxygen-electrode electrocatalyst exhibited a high reversibility (140 cycles) and a stable rate capability (50-500 mA g(-1)). Additionally, electrochemical impedance spectroscopy measurements indicated that the electronic conductivity of a SeZnO3 nanosheet was higher than that of ZnO. Therefore, we propose that the unique SeZnO3 structure exhibits excellent catalytic activity and electrical conductivity and can serve as a route towards improved lithium-oxygen batteries.