Single step synthesized three dimensional spindle-like nanoclusters as lithium-ion battery anodes

Abstract

A novel, facile, and one-step conventional heating method is developed to synthesize monodisperse Sn-doped Fe₂O₃ nanoclusters with a novel spindle-like 3D architecture. The morphology and size of the products can be controlled by adjusting the reaction time and the concentration of additive Sn ions, which are the two affecting factors for the synthesis mechanism. As a proof-of-concept demonstration of their function, our spindle-like Sn-doped Fe₂O₃ nanoclusters present a large capacity of 938 mA h g⁻¹ at 0.2 C after 100 cycles as compared with bare SnO₂ and Fe₂O₃ nanoparticles. Importantly, the capacity is about 805 mA h g⁻¹ at 1 C with a capacity retention as high as 95% after 500 cycles when used as lithium ion battery anodes. This excellent electrochemical performance benefits from the successful doping and their 3D assembled structure, which help improve the conductivity, overcome the large volume changes and stresses during the charge–discharge reaction and finally result in the superior cycling performance and charge-rate capabilities.