Hexagonally arranged monodisperse silver nanowires with adjustable diameter and high aspect ratio

Monodisperse silver nanowires with high aspect ratio are prepared via electrochemical plating into monodomain porous alumina templates. The nanowires have a length of 30 mum or more, adjustable uniform diameters ranging between 180 and 400 nm, and a monodispersity of about 2%. The templates were fabricated by anodization of imprinted aluminum with an interpore distance of 500 nm. Nearly 100% pore filling was obtained due to a thinning process which guaranteed a barrier layer of homogeneous thickness of a few nanometers. Moreover, hierarchically ordered porous alumina with about 25-nm-40-nm pore diameter on one side and 180-nm pore diameter on the other side was successfully infiltrated by the same method, yielding branched silver nanowires.