Template-assisted electrodeposition of SixGe1-x nanowires with varying length and composition from two different ionic liquids

We have recently reported that "luminescent'' SixGe1-x can be electrodeposited from 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl) amide ([Py-1,Py-4]Tf2N) at room temperature. nterestingly, 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl) amide ([EMIm]Tf2N) ionic liquid delivers a germanium-rich SixGe1-x showing also a quantum-size effect, as revealed in the present study. These results led us to evaluate the possibility of obtaining high quality SixGe1-x nanowires from two different ionic liquids by the simple and inexpensive template-assisted electrochemical pathway. Herein, we report for the first time on the room temperature template synthesis of SixGe1-x nanowires by potentiostatic electrochemical deposition from the air-and water-table ionic liquids [Py-1,Py-4]Tf2N and [EMIm]Tf2N containing (each) GeCl4 and SiCl4 as precursors. As a first step, a commercially available track-etched polycarbonate membrane (PC) with an average nominal pore diameter of 90 nm was used as template. SixGe1-x nanowires with an average diameter corresponding to the nanopores' diameter and lengths of 1 to 2.5 mu m were reproducibly obtained. [EMIm]Tf2N delivers longer SixGe1-x nanowires than [Py-1,Py-4]Tf2N under the same parameters and reaction conditions. Characterization of the nanowires was performed by EDX and HR-SEM.