A novel self-supported porous ZnO nanobelt arrays on Zn foils: excellent binder-free anode materials for LIBs.

ZnO is considered to be one of the promising anode materials for lithium-ion batteries, but the poor electronic conductivity and large volume variation during lithium-ion extraction and insertion process of ZnO seriously hinders its commercial application in lithium-ion batteries (LIBs). In this study, we synthesized a novel self-supporting porous ZnO nanobelt (PZB) arrays on Zn foils, in which Zn foils can be directly used as current collectors to promote electrically connection between the active materials and the current collectors. Furthermore, the well-aligned ZnO nanobelts have a thin thickness and uniform porous structure, which endue it well improved electrochemical performance. The PZB anodes display a high areal capacity of 5.91 mAh cm-2 at current density of 0.5 mA cm-2 at room temperature, and deliver an areal capacity of 1.73 mAh cm-2 at -20 °C, indicating its excellent application potential especially at low temperatures, and it makes the porous ZnO nanobelts a practical anode material for lithium-ion batteries.