Growth and Characterization of Ordered PbO[sub 2] Nanowire Arrays

Abstract

Large arrays of PbO2 nanowires having high aspect ratios (length-to-width ratio) were grown by potentiostatic electrodeposition into anodic alumina templates under anodic polarization. Different electrolytic solutions were used in order to obtain nanowires of pure α-PbO 2, pure Β-PbO2, and a α+Β mixture. We have found that, in a lead nitrate bath, a crystallographic structure of nanowires depends on pH; this latter was varied adding diluted nitric acid to the electrolyte. Nanowires of pure Β-PbO2 were obtained at pH 0.6, while mixed α-PbO2 +Β-PbO2 nanowires were grown at pH 2. Pure α -phase was obtained in a bath containing lead acetate at pH 6.6. In all deposition conditions, nanowires present the same morphology: perfectly cylindrical wires having uniform diameters throughout length, with an average value of ∼210 nm and a population density on the order of 10 13 wires/ m2. Very high aspect ratios were obtained already after 30 min of electrodeposition. © 2008 The Electrochemical Society.