Continuous electrodeposition of silicon and germanium micro⁄nanowires from their oxides precursors in molten salt

Abstract

Abstract In recent years, silicon (Si) and germanium (Ge) materials have been considered as promising high-performance anode materials for lithium-ion batteries due to their high theoretical capacities. It is of great importance to design and synthesize micro/nanostructured Si and Ge materials. In this work, we demonstrated that Si, Ge and SiGe micro/nanowires can be continuously synthesized from their oxides precursors through molten salt electrodeposition. The electrochemical synthesis processes have been investigated systematically, and the deposited Si, Ge and SiGe micro/nanowires have been characterized and compared. The results show that the micro/nanostructured Si and Ge materials with tunable morphology can be facilely and continuously produced via molten salt electrodeposition. The electrodeposition process generally includes calcium oxide-assisted dissolution and electrodeposition processes, and the morphologies of the deposited Si and Ge products can be controlled by varying conditions. Si micro/nanowires, Si films, Ge micro/nanowires, and Ge particles can be continuously synthesized in a controlled manner.