Reduced graphene oxide uniformly anchored with ultrafine CoMn2O4 nanoparticles as advance anode materials for lithium and sodium storage

Abstract

Graphene and metal oxide nanocomposites have been demonstrated as promising electrode materials for high-performance lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs). In this work, ultrafine CoMn2O4 nanoparticles uniformly anchored on reduced graphene oxide (rGO) sheets have been synthesized through a facile and effective two-step strategy. Owing to the rational combination of merits from both ternary CoMn2O4 and graphene sheets, the as-synthesized rGO/CoMn2O4 nanocomposite exhibits remarkable Li-battery performance with high reversible capacity, good cycling stability and excellent rate performance. Remarkably, the rGO/CoMn2O4 nanocomposite displays high reversible capacities of 1102.1 and 811.1 mA h g−1 at the current densities of 200 and 500 mA g−1 after 60 cycles, respectively. The discharge capacities of the rGO/CoMn2O4 nanocomposite are as high as 851.1, 835.3, 795.2, 755.9, 694.0, and 563.6 mA h g−1 at the current densities of 100, 200, 500, 1000, 2000 and 5000 mA g−1, respectively. These electrochemical results suggest the rGO/CoMn2O4 nanocomposite could be a promising anode material for high-performance LIBs. Besides, the rGO/CoMn2O4 nanocomposite also exhibits comparably promising electrochemical performance as an anode material for SIBs. Our study also highlights the importance of rational synthesis of graphene-based nanocomposite materials for high-performance LIBs and SIBs.