Synthesis and performance of apple-like tin oxide as anode for Li-ion batteries

Apple-like SnO2 was synthesized by one-step template-free solvothermal method. X-ray diffraction, scanning electron microscopy and transmission electron microscopy were conducted to characterize the products. It was demonstrated that the products contained SnO2 crystalline phase and SnO2 particles were almost spherical with a one-side open hole, resembling an apple shape. The hole's diameter ranged from 1 μm to 10 nm. The N2 sorption isotherm test gave a result that the adsorption average pore diameter of the holes was 8.7939 nm and the BET surface area was as high as 94.6447 m2/g. The results of infrared spectroscopy showed that the apple-like SnO2 displayed an antisymmetric vibration mode of SnOSn with hydroxyl groups on the surface. The apple-like SnO2 performed good cycling stability with a reversible capacity of 712 mAh/g after 30 cycles, nearly twice as high as commercial SnO2 powder.