Growth and dissolution of NaO2 in an ether-based electrolyte as the discharge product in the Na–O2 cell

Abstract

The deposition and dissolution of sodium superoxide (NaO₂) was investigated by atomic force microscopy. Rectangular prisms consisting of 8 smaller sub-structures grew from NaO₂ platelets, when discharged in 0.5 M NaClO₄, diethylene glycol dimethyl ether on highly ordered pyrolytic graphite. During oxidation the 8 sub-structures are conserved. Ring-like structures of Na₂CO₃ of 200 nm diameter remain at the end of oxidation.