Hierarchical LiZnVO4@C nanostructures with enhanced cycling stability for lithium-ion batteries

Abstract

Hierarchical LiZnVO₄@C nanostructures composed of thin nanobelt aggregates were synthesized for the first time through an ethanol thermal and subsequent annealing route, and were investigated by X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Furthermore, the synthesized hierarchical nanostructures were used as anode materials for Li-ion intercalation and exhibited a large reversible capacity, high rate performance, and excellent cycling stability. For instance, a high reversible capacity of 675 mA h g⁻¹ was maintained after 60 cycles at a current density of 50 mA g⁻¹. These results might be attributed to the following facts: (i) the hierarchical nanostructures could buffer the strain and volume changes during the cycling process; (ii) the thin nanobelts provide a shortened distance for Li-ion intercalation; (iii) the thin carbon layer on the surface of the nanobelts could provide a fast route for electron transportation, leading to an improved capacity and high rate performance.