Carbon-coated Fe3O4 microspheres with a porous multideck-cage structure for highly reversible lithium storage

A novel H3PO4 etching strategy together with subsequent carbon coating has been developed for the synthesis of carbon-coated Fe3O4 microspheres with a porous multideck-cage structure. These carbon-coated Fe3O4 microspheres manifest high specific capacity (∼1100 m h g−1 at 200 mA g−1) and excellent cycling stability for lithium storage.