T-shaped Bi₂Te₃-Te heteronanojunctions: Epitaxial growth, structural modeling, and thermoelectric properties

Abstract

Novel T-shaped Bi2Te3-Te heteronanojunctions composed of a rhombohedral structured Bi2Te3 nanoplate and a trigonal structured Te nanorod were fabricated by a simple and facile solvothermal method. A unique crystallographic relationship of [21̄1̄0]Bi2Te3/[21̄1̄0]Te and [0001]Bi2Te3//[0001]Te has been observed for this epitaxial growth. Such epitaxial nature between Bi2Te 3 nanoplates and Te nanorods is caused by their negligible lattice mismatches in the corresponding atomic planes. The interfaces between Bi 2Te3 nanoplates and Te nanorods lead to a low thermal conductivity in these heteronanojunctions, so that a promising figure of merit (ZT) value is obtained (0.73 ± 0.04 at 320 K). This study provides a new method and opportunity to engineer heteronanojunctions for high-efficiency thermoelectric devices for power generation. Show more