Electrochemically assembled p-type Bi2Te3 nanowire arrays

Polycrystalline Bi2Te3 nanowires with diameter about 50 nm have been assembled into the nanopores of alumina template by electrodeposition in the solution containing Bi3+ and HTeO2+ with porous alumina template as a cathode. X-ray photoelectron spectroscopy, high-resolution electron microscopy, and selected area electron diffraction investigations indicate that the nanowires are polycrystalline Bi2Te3 with hexagonal structure. Transmission electron microscopy and environmental scanning electron microscopy are used to characterize the morphology of the Bi2Te3 nanowire arrays. The performance measurements verified that the Seebeck coefficient of p-type Bi2Te3 nanowire arrays prepared in our lab was 270 muV/K at 306 K, which is larger than that of bulk Bi2Te3 thermoelectric materials. The temperature dependence of the resistance of the nanowire arrays was also measured, and it showed a semiconductive characteristic. (C) 2004 American Institute of Physics.