Dresden 2009 – wissenschaftliches Programm
DS 16.38: Poster
Dienstag, 24. März 2009, 09:30–12:30, P5
Thermoelectric Multilayered Nanowires Grown by Single-Bath Electrodeposition — •William Töllner1, Johannes Kimling1, Renbin Yang2, and Kornelius Nielsch1 — 1University of Hamburg, Institute of Applied Physics, Jungiusstrasse 11, 20355 Hamburg — 2Max Planck Institute of Microstructure Physics, Weinberg 2, 06120 Halle
Thermoelectric (TE) modules offer tremendous advantages over conventional cooling and power conversion systems such as scalability and reliability. However, poor efficiency has prevented the commercial breakthrough for TE coolers and generators. Theoretical works predict a huge increase of ZT, the TE figure of merit, in nanostructured materials. One promising approach to achieve higher ZT values are superlattices and nanowires, both reducing thermal conductivity due to phonon scattering effects while keeping a high electrical conductivity. In this work, we have grown Bi-Sb-Te alloy superlattice nanowires in porous alumina membranes by electrodeposition. Deposition of multilayered wires has been performed out of one electrolyte by modulating the electrochemical potential. The aqueous solution containing bismuth, antimony, and telluride ions has been investigated by voltammetric methods. Alumina membranes with a pore diameter of about 50 nm were fabricated by two-step anodization. The composition of Bi-Sb-Te alloyed nanowires has been investigated using TEM-EDX. Preliminary results for filled membranes will be presented: Xenon-Flash-, 3-Omega-measurements (thermal diffusivity/conductivity) and Seebeck-micro-probe scans.