Porous SnO2-Fe2O3 nanocubes with improved electrochemical performance for lithium ion batteries.

Mixed oxide SnO2-Fe2O3 porous nanocubes were prepared by simply annealing the precursor of Sn3[Fe(CN)6]4 nanocubes, which were obtained through a facile solvothermal method. Calcination of the precursor at 350 °C produced uniform SnO2-Fe2O3 nanocubes without obvious morphological deformation, but with lots of open void space in the nanocubes. The Brunauer-Emmett-Teller N2 adsorption-desorption analysis shows that the as-synthesized SnO2-Fe2O3 has a specific surface area of 170.2 m(2) g(-1) with a pore size of around 5 nm. The porous SnO2-Fe2O3 nanocubes as anode materials for the lithium-ion battery show a high initial capacity of 1020.2 mA h g(-1) at a current density of 200 mA g(-1) and maintain at 567.5 mA h g(-1) at the 50th cycle, which is distinctly higher than those reported for SnO2-based materials. The enhanced performance towards lithium storage can be ascribed to the high specific area, an appropriate pore size and the synergistic effect of SnO2 and Fe2O3.