An efficient electrocatalyst of NiO supported on carbon paper for nonaqueous Li–O2 batteries

Abstract

A Li–O2 battery has been considered as one of the most promising energy storage systems owing to their ultrahigh theoretical energy densities. However, low energy efficiency (high polarization) during discharge/charge and resulting cycle stabilities have severely limited the development of this type of battery. Here, we demonstrate a simple preparation of NiO supported on carbon paper by dipping carbon paper in Ni acetate solution and heating it to apply NiO directly to the carbon as a cathode material for nonaqueous Li–O2 batteries. The prepared sample was confirmed as the structure of NiO-incorporated carbon using X-ray photoelectron spectroscopy (XPS), X-ray absorption spectroscopy (XAS), and high-resolution transmission electron microscopy (HR-TEM) analysis despite amorphous patterns seen in XRD (~ 10% NiO in NiO supported on carbon paper). A Li–O2 cell in which the NiO supported on carbon paper was applied as an electrocatalyst showing an initial ~ 6% increase in energy efficiency and a subsequent 50 cycle retention.