Improving the Performance of Perovskite in Nonaqueous Oxygen Electrocatalysis.

ABSTRACT

Nanoparticle (NP) aggregates of lanthanum cobalt oxide perovskite (LCO) were compounded with reduced graphene oxide (rGO) nanosheets and used as the cathode catalyst for nonaqueous lithium-oxygen batteries (LOBs). The LCO NP aggregates were completely surrounded by rGO nanosheets in the composite with 10.5 wt % of rGO (LCO-rGO-10.5) but were partially exposed in the composite with 7.5 wt % of rGO (LCO-rGO-7.5). Both composites performed better than pristine LCO NPs and rGO nanosheets in nonaqueous oxygen electrocatalysis. The LCO-rGO-7.5 composite excelled at capacity and rate performance, while the LCO-rGO-10.5 composite was better at cycle stability. The good performance of the LCO-rGO composites was due to the synergy of functions of LCO and rGO.