Microwave-assisted one-pot synthesis of SnC2O4/graphene composite anode material for lithium-ion batteries

Currently, SnC2O4 is considered as one of the most promising anode materials for high-energy lithium-ion batteries (LIBs) because its charge capacity is higher than that of metal oxides. Herein, a facile microwave-assisted solvothermal method was employed to obtain SnC2O4/GO composites within only 30 min, which is time-efficient. The amount of SnC2O4 was increased to 95.3 wt% to improve the capacity of the composite. Pure SnC2O4 with a high specific surface area of 19.6 m2 g−1 without any other tin compound was used for fabrication. The SnC2O4/GO composite exhibited excellent electrochemical performance, with reversible discharge/charge capacity of 657/659 mA h g−1 after 100 cycles at 0.2 A g−1. Furthermore, at high current densities of 1.0 and 2.0 A g−1, the SnC2O4/GO composite anode exhibited high reversible discharge/charge capacities of 553/552 and 418/414 mA h g−1, respectively, after 200 cycles at room temperature. These improvements were likely obtained because SnC2O4 was well composited with graphene, which not only offered rapid electron transfer but also released the tension produced by the volumetric effect during repeated lithiation/delithiation. Cyclic voltammetry (CV) was also performed to further study the electrochemical reactions of SnC2O4/GO. The facile microwave-assisted solvothermal method used herein is considered as a highly efficient method to fabricate metal oxalate/graphene composites for use as anode materials in LIBs.