A new one-dimensional gradient material with graded sizes was prepared. A two-step anodic oxidation of high purity aluminum was used to fabricate porous alumina templates with graded pore sizes. Based on the templates, metal silver graded nanowires were obtained by electrochemical deposition. SEM and TEM results show that the resulted metal silver nanowires have obvious graded diameters with gradient ranging from about 12 to 31 nm along the nanowire direction, and are single-crystalline with a preferential growth along <100> direction.
