Layer-stacked Sb@graphene micro/nanocomposite with decent Na-storage, full-cell and low-temperature performances

Abstract Resolving the large volume changes and achieving the ultrafast charge-discharge capability for the alloy anode of sodium-ion batteries (SIBs) are needed urgently. Rational design of unique structure is an effective strategy to solve these problems. Herein, we reported a facile route to synthesize a layer-stacked Sb@graphene (LS-Sb@G) micro/nanocomposite via solvothermal method by using a mild reducing agent. In the LS-Sb@G, the Sb nanosheets are uniformly pasted on the graphene matrix and embedded into the interlayers, which leading to the formation of tight layer-by-layer micro/nanostructure. When employed as anode materials for SIBs, the unique structural characteristics offer the LS-Sb@G micro/nanocomposite with impressive Na-storage properties, such as high Na-storage capacity of 495.2 mAh/g after 100 cycles at 125 mA/g and decent rate capabilities up to 6 A/g. In addition, the LS-Sb@G electrode achieves superior electrochemical performance with a high reversible capacity of 116.5 mAh/g at 0.1 C (1 C = 120 mA/g) for sodium-ion full cells. Moreover, we firstly studied the low-temperature Na-storage performance of Sb-based composite at −20 °C. The LS-Sb@G composite demonstrated good low-temperature properties (e.g., 506.6 and 472.5 mAh/g at 25 and 50 mA/g at −20 °C, respectively) for SIBs, which endow great promise as an anode material for the normal operation of electric vehicles under low temperature condition.