Growth of single-crystalline BiTe hexagonal nanoplates with and without single nanopores during temperature-controlled solvothermal synthesis.

Bismuth telluride (BiTe) is a promising thermoelectric material for applications near room temperature. To increase the thermoelectric performance of this material, its dimensions and thermal transport should be decreased. Two-dimensional nanoplates with nanopores are an ideal structure because thermal transport is disrupted by nanopores. We prepared BiTe nanoplates with single nanopores by a solvothermal synthesis and investigated their structural and crystallographic properties. The nanoplates synthesized at a lower reaction temperature (190 °C) developed single nanopores (approximately 20 nm in diameter), whereas the nanoplates synthesized at a higher reaction temperature (200 °C) did not have nanopores. A crystal growth mechanism is proposed based on the experimental observations.