1-dodecanthiol-assisted aqueous synthesis and characterization of Bi2Te3 nanotubes

Bidur Rijal (1) , Aigerim Baimyrza (1) , Thibault Parein (1) , Quentin Lonne (1) , David Blond (1) , Richard Retoux (2) , Franck Gascoin (2) , Loïc Le Pluart (1) , Cyprien Lemouchi (1)

1 LCMT - Laboratoire de chimie moléculaire et thioorganique
2 CRISMAT - Laboratoire de cristallographie et sciences des matériaux

This article reports a novel synthetic methodology for preparing Bi2Te3 nanotubes as well as tailoring their size and aspect ratio, which provides a strong potential interest in the field of thermoelectrics. Bi2Te3 nanotubes were synthesized via a 1-dodecanethiol (DDT) assisted aqueous two-steps synthesis. One of its main advantages is to be easily scalable because it is carried under mild experimental conditions. The complexation of the capping ligand DDT to the bismuth yields to layered structural complexes Bi(DDT)3, which may act as a soft templates promoting the growth of Bi2Te3 nanotubes. The products were characterized by X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Energy Dispersive X-ray analysis (EDX), Transmission Electron Microscopy (TEM) and High-Resolution Transmission Electron Microscopy (HRTEM). Microstructure investigations of powders show that the Bi2Te3 nanotubes are 200–500 nm long with an average diameter of 50–100 nm. The HR-TEM and selected area electron diffraction (SAED) results reveal the presence of 20–30 nanometers crystallized nanodomains and support the growth of the nanotubes via a rolling up mechanism of (a, b) planes. Using sodium dodecylbenzene-sulfonate (SDBS), as an additional structuring agent, lowers the yield of Bi2Te3 tubes synthesis and increases the heterogeneity of their size distribution. However, with an increased amount of SDBS very long Bi2Te3 (up to 20 µm) tubes have been obtained. As a conclusion, using the capping ligand DDT allows obtaining Bi2Te nanotubes in mild conditions according to an easily scalable procedure. Moreover, for the first time the addition of another shape directing agent such as the surfactant SDBS in presence of DDT is shown to be a promising way to tune the dimensions and aspect ratio of these Bi2Te3 nanotubes, and as a consequence tailor their electronic properties, since the longest hollow Bi2Te3 tubes ever synthesized have been obtained.

Mots clés: Bi2te3; Nanotubes; Capping ligand; Structuring agent; X-ray diffraction; Scanning electron microscopy (SEM)

Domaines: Matériaux

Bidur Rijal, Aigerim Baimyrza, Thibault Parein, Quentin Lonne, David Blond, et al.. 1-dodecanthiol-assisted aqueous synthesis and characterization of Bi2Te3 nanotubes. Nano-Structures & Nano-Objects, 2021, 25, pp.100629. ⟨10.1016/j.nanoso.2020.100629⟩. ⟨hal-03137196⟩