Facile Mechanochemical Synthesis of Nano SnO2/Graphene Composite from Coarse Metallic Sn and Graphite Oxide: An Outstanding Anode Material for Lithium-Ion Batteries

A facile method for the large-scale synthesis of SnO2 nanocrystal/graphene composites by using coarse metallic Sn particles and cheap graphite oxide (GO) as raw materials is demonstrated. This method uses simple ball milling to realize a mechanochemical reaction between Sn particles and GO. After the reaction, the initial coarse Sn particles with sizes of 3-30m are converted to SnO2 nanocrystals (approximately 4nm) while GO is reduced to graphene. Composite with different grinding times (1h 20min, 2h 20min or 8h 20min, abbreviated to 1, 2 or 8h below) and raw material ratios (Sn:GO, 1:2, 1:1, 2:1, w/w) are investigated by X-ray diffraction, X-ray photoelectron spectroscopy, field-emission scanning electron microscopy and transmission electron microscopy. The as-prepared SnO2/graphene composite with a grinding time of 8h and raw material ratio of 1:1 forms micrometer-sized architected chips composed of composite sheets, and demonstrates a high tap density of 1.53gcm(-3). By using such composites as anode material for LIBs, a high specific capacity of 891mAhg(-1) is achieved even after 50 cycles at 100mAg(-1).