The Self-assembled SnO₂-FeO(OH) on Natural Graphite Surface as A High-capacity Anode for Lithium Ion Batteries

A stable H₂SnO₃@Fe(OH)₃ colloidal solution is prepared through double hydrolysis. It is self-assembled on the surface of natural graphite under the action of electrostatic adsorption. After the hydrothermal reaction, the H₂SnO₃@Fe(OH)₃ colloidal micelles on the surface of graphite are changed into SnO₂-FeO(OH) co-dispersed structures. The structural characterizations show that there is a dense nanostructure coating on the surface of natural graphite after hydrothermal reaction, composed of ultrafine SnO₂ nanocrystalline particles (< 6 nm) and amorphous FeO(OH). The electrochemical testing results indicate that the SnO₂-FeO(OH) fine nanostructures can not only improve the charge/discharge capacity of graphite, but also improve its cyclic stability. At a current density of 0.1C, the initial cycle efficiency of the modified graphite can reach 77.5%. After 100 cycles, the discharge capacity of modified graphite can be maintained at 384.4 mAh/g, which is 23% higher than that of commercial graphite.