A solvothermal induced self-assembling of SnO₂/exfoliated graphite composite with enhanced lithium storage performances

A new solvothermal induced self-assembling method was investigated for the facile synthesis of SnO₂/exfoliated graphite (EG) composite without any structure-directing agents. With the assistance of solvothermal treatment in an acetone-H₂O mixture, ultra-small SnO₂ nanoparticles of less than 10 nm could be transformed from a metastable state in colloidal solution to a highly-dispersed state on the inert surface of EG which was not acid-treated beforehand. The preparation conditions such as solvothermal time and SnO₂ adding amount were found to be important factors influencing the structure and electrochemical performance of the composites. The half-sell using the SnO₂/EG composite as an electrode exhibited a greatly enhanced lithium storage capacity of 910 mAh g⁻¹ at the current density of 100 mA g⁻¹ after 200 cycles and a moderate rate capability of 385 mAh g⁻¹ at 1000 mA g⁻¹. Compared with previous studies, this solvothermal induced self-assembling process supplies not only a promising anode material for newly advanced Li-ion batteries, but also a green and scalable approach for the preparation of metal oxide/carbon composites.