Self-supported Zn/Si core-shell arrays as advanced electrodes for lithium ion batteries

Silicon is considered as the most promising substitute for the commercial graphite anode of lithium ion batteries (LIBs) dim to its high capacity and low working voltage. In this work, we realize the rational combination between Zn nanorods and Si forming self-supported Zn/Si core-shell arrays with the aid of hydrothermal and sputtering methods. Amorphous Si layer is well coated on the backbone of Zn nanorods with diameters of 70-80 nm. As a preliminary test, the Zn/Si core-shell arrays are used as the anode of LIBs and demonstrated with a high initial reversible capacity of 2795 mAh g(-1) at 0.1C, good high-rate capability with 1985 mAh g(-1) at 1C and stable cycling life. The good performance is due to the highly conductive Zn nanorod network and porous core-shell structure providing good mechanical support and fast transport of ions/electrons.