Sb embedded TiO2/C spheres as high cyclability anode for lithium ion battery

Abstract

Hollow TiO2/Sb/C spheres that nano Sb embedded into the interlayer between inner hollow TiO2 sphere and outer carbon layer, were designed, synthesized and investigated. The physical properties were studied by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The electrochemical performances were acquired by discharge/charge cycles, rate cycles, cyclic voltammograms (CVs) and electrochemical impedance spectra (EIS). The results indicated that nano Sb embedded did not decline the cycle stability and rate property of TiO2/C anode, but its reversible capacity was increased by a large margin. Li+ diffusion coefficient of TiO2/Sb/C-2 and TiO2/Sb/C-1 reached to 4.76 × 10−16 cm2 s−1 and 4.10 × 10−16 cm2 s−1, while the value of TiO2/C was 2.46 × 10−16 cm2 s−1. At 1000 mA g−1, initial reversible capacity for TiO2/Sb/C-2 reached to 230.6 mAh g−1, and its capacity loss per cycle was only 0.0201% from 2nd to 1200th cycle. This work provided a conception to manufacture high capacity TiO2-based anodes for lithium ion battery.