▎ 摘 要
Nonaqueous lithium-oxygen battery with nitrogen-doped graphene nanosheets (N-GNSs) as cathode materials delivered a discharge capacity of 11660 mAh g(-1), which is about 40% higher than that with the pristine graphene nanosheets (GNSs). The electrocatalytic activity of N-GNSs for oxygen reduction in the nonaqueous electrolyte is 2.5 times as that of GNSs. The excellent electrochemical performance of N-GNSs is attributed to the defects and functional groups as active sites introduced by nitrogen doping. (C) 2012 Elsevier B.V. All rights reserved.