Fe2O3@SnO2 nanoparticle decorated graphene flexible films as high-performance anode materials for lithium-ion batteries

A flexible graphene film decorated with spindle-like Fe2O3@SnO2 nanoparticles was fabricated through vacuum filtration of Fe2O3@SnO2 and GO mixing solution, followed by thermal reduction. The core-shell structured Fe2O3@SnO2 nanoparticles were synthesized through a facile hydrothermal route, which avoided agglomeration of Fe2O3 and SnO2 nanoparticles and was beneficial for electrolyte diffusion. Microstructure characterizations showed that the spindle-like Fe2O3@SnO2 nanoparticles were uniformly dispersed between layered graphene nanosheets, forming a sandwich-like structure. The unique interleaved structure was favorable for lithium ion diffusion and electron transfer. As binder-free electrodes for lithium-ion batteries, the flexible Fe2O3@SnO2/GS films exhibited discharge and charge capacities of 2063 and 1255 mA h g(-1) respectively, with an excellent cycling performance of 1015 mA h g(-1) even after 200 cycles. The specific capacity of the Fe2O3@SnO2/GS electrode is higher than that of both Fe2O3/GS and SnO2/GS electrodes, indicating a positive synergistic effect of Fe2O3 and SnO2 on the improvement of electrochemical performance.