Effect of oxygen-containing functional groups of carbon materials on the performance of Li-O2 batteries

In this communication, we present some new findings on surface oxidized carbon nanotubes (CNTs) when used as cathode of Li-O2 batteries. It is found that the content of oxygen-containing functional groups has a significant influence on the electrochemical performance of Li-O2 batteries, by altering the electrical conductivity and density of electrocatalytically active sites of the CNTs and promoting side reactions of the electrolyte. An optimal surface oxygen atomic content of 6.0 at.% on CNTs is found to reach a balance and give the best cycling stability of the Li-O2 battery under constant capacity and constant current density tests.