Tin-based oxide microsphere reinforced by Al2O3 and CNT with superior lithium storage performance

To improve lithium storage performances of tin-based oxide electrodes, i.e. SnO2 microspheres reinforced by Al2O3 and CNTs (SnO2-Al2O3/CNT) are constructed using a convenient microwave-assisted method. The findings indicate that the SnO2-Al2O3/CNT composite predominantly consisted of the rutile structure phase, with a minor presence of the orthorhombic phase. SnO2-Al2O3/CNT electrodes demonstrate greater capacity, significantly enhanced cyclability and improved rate performance when compared to the electrodes based on SnO2-Al2O3 and SnO2. Specifically, a sable specific capacity of 745.34 mAh/g can be maintained at 1.0 A/g, while a large specific capacity of 617.36 mAh/g can still be demonstrated at a high current density of 4.0 A/g after 100 cycles. The improved Li-storage performances may be attributed to by the significant synergistic effect among SnO2, Al2O3, CNTs, and the morphology as well.