CeO2 Supported on Reduced Graphene Oxide as Li-O2 Battery Cathode

Li-O 2 battery(LOB) has an ultrahigh specific capacity(3500 W·h/kg), however, its slow kinetics of oxygen reduction reaction(ORR) and oxygen evolution reaction(OER) at cathode often leads to a high overpotential, a limited discharge capacity, and a poor cycling performance. Therefore, it is important to design and prepare cathode materials with a excellent catalytic activity. In this study, CeO 2 nanoparticles(NPs) supported on reduced graphene oxide(rGO) have been prepared and employed as cathode. Compared with either CeO 2 NPs or rGO, CeO 2 /rGO cathode greatly improves the discharge capacity(10644 mA·h/g at a current density of 100 mA/g) and the cycling performance(95 cycles at 200 mA/g with a limited capacity of 500 mA·h/g) by virtue of the good conductivity of rGO and the oxygen storage/release capability of CeO 2 .