CuO ultrathin nanosheets decorated reduced graphene oxide as a high performance anode for lithium-ion batteries

Abstract Two-dimensional (2D) nanocomposites, based on graphene and transition metal oxides, hold great promise as high-performance electrode materials for next-generation lithium-ion batteries. Herein, a novel 2D CuO/RGO has been constructed by CuO ultrathin nanosheets and reduced graphene oxides (RGO) through in-situ oxidizing the Cu/RGO nanocomposite with hydrogen peroxide. CuO nanosheets with a thickness of 1.17–1.57 nm are uniformly and tightly anchored on the RGO surface without aggregation and thus the as-prepared CuO/RGO nanosheets electrode show strong interfacial coupling and fast electron transfer. Electrochemical characterizations reveal that the CuO/RGO nanocomposite electrode exhibits a remarkably enhanced cycling performance and rate performance. At the current density of 0.1C, the initial discharge capacity of 811 mAh/g has been delivered by CuO/RGO nanosheets electrode and the coulombic efficiency maintains 99.44% after 100 cycles. Moreover, the CuO/RGO nanosheets exhibit a stable specific capacity of 386 mAh/g after 200 cycles at 3C. In addition, the as-prepared CuO/RGO nanocomposite electrode exhibited excellent rate performance and lower charge transfer resistance. The current study presents a feasible route to fabricate nanosheets electrode materials for next-generation energy storage devices.