Preparation and characterization of metal Fe nanowires with graded diameter

Based on the porous anodic aluminum oxide templates with a graded pore diameter, Fe nanowires were achieved using alternating current electrochemical deposition. SEM and TEM results show that Fe nanowires have obviously graded diameters along the nanowirepsilas direction with gradient ranging from about 12 to 31nm. High-resolution TEM analysis indicates that the gradient Fe nanowires have a preferential growth along <111> direction. Melting-behavior suggests that diameter-graded Fe nanowires have a graded melting point along one-dimensional direction, which will be of great fundamental and practical interests. It is expected that the ability to fabricate the gradient nanowires could open up new opportunities for fundamental studies and the application of nanostructures.