Electrochemical performance of highly mesoporous nitrogen doped carbon cathode in lithium-oxygen batteries

摘要

Nitrogen doped carbon with a high surface area was used as cathode electrode in a solid-state lithium-oxygen battery. Various techniques including the Brunauer-Emmett-Teller (BET) surface area, X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX) were employed to evaluate the nitrogen functionality on carbon. The electrochemical properties of nitrogen doped carbon as cathode electrode in lithium-oxygen battery were studied using galvanostatic charge-discharge characteristics and electrochemical impedance spectroscopy (EIS). The lithium-oxygen cell fabricated with nitrogen doped Ketjenblack-Calgon activated carbon cathode exhibits two times higher discharge cell capacity than that of a cathode composed of only Ketjenblack-Calgon activated carbon. This work shows that the nitrogen functionality on carbon is responsible for the electro-catalytic activity of cathode and an enhancement in cell capacity of lithium-oxygen battery.