▎ 摘　　要

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. (C) 2017 Elsevier B.V. All rights reserved.