Template-free synthesis of hollow α-Fe2O3 microcubes for advanced lithium-ion batteries

Hollow alpha-Fe2O3 microcubes were fabricated by a facile hydrothermal method in an ethanol-water co-solvent system. The as-synthesized microcubes have a uniform size with an edge length of about 1.5 mu m. Time and solvent proportion dependent experiments reveal that the ethanol adsorption and surface-protected etching mechanisms play key roles in the formation hollow cubic structures. Compared with their solid counterparts, hollow alpha-Fe2O3 microcubes show an enhanced electrochemical performance in terms of long-term cycling (458 mA h g(-1) at a current density of 100 mA g(-1) after 100 cycles) and high rate capability (859, 855, 688 and 460 mA h g(-1) at current densities of 100, 200, 500 and 1000 mA g(-1), respectively). These remarkable electrochemical properties can be attributed to the unique hollow microstructure, which could retain structural stability, relieve stress and increase reaction areas.