Bismuth telluride (Bi2Te3) nanowires synthesized by cyclic electrodeposition/stripping coupled with step edge decoration

Polycrystalline bismuth telluride (Bi2Te3) nanowires have been prepared by the step edge selective electrodeposition of Bi2Te3 on highly oriented pyrolytic graphite (HOPG) surfaces. Bi2Te3 nanowires were obtained from an aqueous plating solution containing Bi3+ and HTeO2+ using a three-step procedure: (1) potentiostatic oxidation of the graphite surface at +0.8 V (vs; saturated calomel electrode, SCE), (2) potentiostatic nucleation Of Bl(2)Te(3) at -0.6 V for 5 ms, (3) growth of Bi2Te3 from these nuclei by cyclic electrodeposition (of both Bi2Te3 and bismuth) and stripping (of bismuth only) between +0.30 V and -0.05 V at 20 mV s(-1). Control of the number of electrodeposition/stripping scans allowed the diameter of Bi2Te3 nanowires to be specified in the range from 100 to 300 nm. Bi2Te3 nanowires were narrowly dispersed in diameter (RSDdla = 10-20%), were up to 1.0 mm in length, and were organized into parallel arrays containing hundreds of wires.