Electrochemical Synthesis and Characterisation of BiTe-Based Nanowire Arrays as Thermoelectric Nanogenerators

Abstract

Thermoelectric (TE) nanogenerators are solid state devices that can directly convert thermal energy into electrical power. The family of bismuth telluride (BiTe)-based semiconductor materials is a good candidate for room-temperature thermoelectric applications. This work aims to synthesize the binary and ternary TE nanowire arrays from BiTe and BiSbTe using template-assisted electrochemical deposition. The compositions and lengths of the nanowires fabricated were precisely tuned by controlling the deposition conditions, while their diameters were confined by the pore sizes of the anodized alumina oxide (AAO) templates used. Chemical compositions of the nanowires were evaluated using Energy Dispersive X-ray (EDX) Spectroscopy and their microstructures were characterized by X-ray diffractometry (XRD), scanning electron microscopy (SEM), conventional transmission electron microscopy (CTEM) and high resolution transmission electron microscopy (HRTEM). TE nanogenerator modules comprising of BiTe and BiSbTe nanowires/AAO composite arrays were fabricated for TE performance evaluation on the basis of their power outputs.