Facile synthesis of Zn2Ti3O8 hollow spheres based on ion exchange as promising anodes for lithium ion batteries

A new approach has been designed to convert typical Stöber silica spheres to Zn2Ti3O8 (ZTO) hollow spheres with different shell thicknesses as anode materials for Lithium ion batteries. The morphologies, structures and synthesis process of ZTO hollow spheres are systematically investigated. X-ray diffraction (XRD) analysis shows that the good ZTO crystal is formed after being sintered at 500 °C for 2 h. The galvanostatic cycle tests exhibit excellent cycling stability, reversibility and low voltage. At a current density of 200 mA g−1, the discharge specific capacities of 186.2 mAh g−1, 173.6 mAh g−1 and 169.9 mAh g−1 have been achieved after 100 cycles, 200 cycles and 300 cycles, respectively. The superior electrochemical performance could be attributed to the hollow structure and characteristics of ZTO crystals. Cyclic voltammetry (CV) curves show symmetrical and stable redox peaks at 1.1 V and 1.5 V for ZTO hollow spheres after the first cycle. Electrochemical impedance spectroscopy (EIS) measurement analysis also indicates that ZTO hollow spheres as anode materials for LIBs have excellent electrochemical performance.