Excellent cyclic performance of Fe2O3@C/SnO2 controlled by Fe2O3@C and SnO2/C hybrid structures for lithium-ion batteries

摘要

A ternary nanocomposite Fe2O3@C/SnO2 is synthesized via a two-step hydrothermal method with further annealing. The crystallinity, micromorphology, and electrochemical performance of Fe2O3@C/SnO2 nanocomposite are systematically characterized. Galvanostatic charge/discharge measurement demonstrates that Fe2O3@C/SnO2 exhibits good rate discharge capacity. It shows a reversible capacity of 540 mAh g(-1) after 1000 cycles operated at a current density of 1000 mA g(-1) with higher Coulombic efficiency. The excellent electro- chemical properties of FFe2O3@C/SnO2 maybe are related to the hybrid structure, in which the carbon layer encloses the needle Fe2O3, meanwhile, the SnO2 nanoparticles disperse into carbon layer. The carbon layer effectively refines the pulverization of SnO2 nanoparticles and avoids the aggregation. The carbon layer loaded SnO2 encircles Fe2O3, which effectively accommodates the internal stress of volume expansion of Fe2O3. The results demonstrate that such the nanocomposite developed here has great potential for application in high-energy lithium-ion batteries.