Si Nanowire Anode Prepared by Chemical Etching for High Energy Density Lithium-ion Battery

Abstract

Silicon nanowire arrays were fabricated by metal-assisted chemical etching of single crystal silicon wafer. Then the silicon nanowire powder was obtained via ultrasonicating from silicon wafer and utilized as the anode elec- trode material of lithium ion battery. The effects of Ag catalyst deposition process and the subsequent anisotropic chemical etching on the formation of silicon nanowires were systematically investigated. The redistribution of Ag par- ticles was found during the chemical etching. The large-area silicon nanowire arrays with proper length-diameter ratio were obtained by optimizing the concentration of AgNO3, HF and H2O2 solution. The silicon nanowires exhibited the classical alloy-reaction plateaus of silicon and the specific capacity above 1800 mAh/g prior to the sixth cycle.