Novel multilayer sandwich-like LiV sub(3)O sub(8) nanosheets-graphene composites with hierarchical structure and enhanced oxygen electro-reduction performance

In this work, multilayer sandwich-like LiV sub(3)O sub(8) nanosheets-graphene (LiV sub(3)O sub(8)-G) composites were initially developed by a facile solution-based assembly followed by a thermal reduction process using graphene oxide sheets, V sub(2)O sub(5) nanobelts and LiOH (aq) as raw materials. The resultant nanocomposites were further determined to be of a unique hierarchical morphology composed of high purity LiV sub(3)O sub(8) nanosheets and graphene sheets layerby-layer alternatively. Moreover, the oxygen reduction reaction (ORR) electrocatalytic performance of LiV sub(3)O sub(8)-G nanocomposites was measured by various electrochemical methods in 0.1 M KOH electrolyte. It is found that LiV sub(3)O sub(8)-G based electrodes show increased activity and stability in comparison with the bare LiV sub(3)O sub(8) electrode. Combined with the analysis of electrochemical impedance spectroscopy (EIS) results, the enhancement can be ascribed to the enlarged conductivity and plentiful interspace due to the introduction of graphene sheets in the nanocomposites.