Synthesis and Thermoelectric Properties of Compositional-Modulated Lead Telluride-Bismuth Telluride Nanowire Heterostructures

摘要

Thermoelectric materials, which can perform a direct conversion between thermal and electrical energy, have created significant interest recently. The thermoelectric device efficiency is determined by the figure of merit (ZT =TS~2σ/k). The fact is that the three factors: Seebeck coefficient (S), electric conductivity (σ) and thermal conductivity (k) are inherently correlated, thus greatly restricting the improvement of ZT. The telluride nanocomposites which have been intensively studied as thermoelectric materials recently show strongly reduced thermal conductivity while maintain high power factor (S~2σ), thus leading to enhanced ZT.