Electro-synthesis of Sn-Co nanowires in alumina membranes

A fabrication process of amorphous nanowires of Sn-Co alloys, based on electrodeposition into anodic alumina membranes, is described. It is shown that nanowires of tin-cobalt alloys with different compositions can be produced by varying electrodeposition time and concentration ratio of salts dissolved into the electrolytic bath. Importance of the chelating agent to produce amorphous Sn-Co alloys has also been addressed. Electrodepositions were carried out potentiostatically at -1 V versus Saturated Calomel Electrode and 60 degrees C for times ranging from 10 to 90 minutes; the atomic fraction of Co2+ in the aqueous electrolyte (Co2+/(Co2+ + Sn2+)) was varied from 0.33 to 0.67. Nanowires aspect ratio (height/width) was controlled by adjusting the deposition time. Alloys were characterized by scanning electron microscopy and X-ray diffraction; compositional analysis was performed by energy dispersive spectroscopy and induced coupled plasma. The highest concentration of Co in the alloy was found after 90 min of electrodeposition from a bath containing 67% of Co2+.