Facile synthesis of Ag-coated silicon nanowires as anode materials for high-performance rechargeable lithium battery

Abstract

Herein, we suggest a facile and cost-effective metal-assisted chemical etching (MACE) method to synthesize uniformly Ag-coated silicon nanowires (SiNWs) using redox reaction, which provides structural and electrical effects on Si negative electrodes at the same time. The combinations of SiNW geometry and Ag nanoparticle (AgNP) coatings are beneficial in preventing pulverization and increasing electrical conductivity of Si negative electrode during cycling, as a result, excellent electrochemical performances are obtained. Transmission electron microscopy (TEM) images reveal that Ag-coated SiNW arrays have been successfully prepared in one-pot MACE process. The electrochemical performances show that the rate capability and cycleability of Ag-coated SiNWs is greatly improved compare to bare NWs. Electrochemical impedance spectroscopy (EIS) measurements show that the electrical conductivity of Ag-coated SiNW electrode is significantly enhanced by Ag coating. © 2015 Elsevier B.V. All rights reserved.