A simple phase transformation strategy for converting silicon nanowires into metal silicide nanowires: Magnesium silicide

The phase transformation of silicon nanowires is studied with the intent of developing a general route for the synthesis of compound semiconductor metal silicide nanowires. Specifically, the reaction of single-crystalline silicon nanowires with magnesium supplied via the vapor phase onto their surfaces for the formation of magnesium silicide (Mg2Si) nanowires is presented. These studies indicated that the nanowire morphology is preserved during the phase transformation process. These observations along with the nucleation and growth steps underlying the phase transformation process are discussed in detail in this manuscript. The results obtained coupled with the fact that electroless etching can be employed for the production of silicon nanowires powders on a large scale provide a path for the mass production of any metal silicide nanowire powder.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Phase transformation of Si nanowire arrays into Mg2Si nanowires was accomplished. ► Controlled magnesium supply allowed for phase change with morphology retention. ► Nucleation and growth steps underlying the nanowire phase transformation discussed. ► Phase transformation is useful for any metal silicide nanowire powder production.